Hi everyone, I found the great question on booting encrypted drives, and since I’m somewhat paranoid I’d like to ask a follow-up:

When the key to decrypt the drive is input into the system, I’m assuming it stays in the RAM till the time the computer shuts downs. We know that one could, in theory, get a dump of the contents of the RAM in such a state, if done correctly. How would you deal with this problem? Is there some way to insert the USB, decrypt the drive, and then remove the USB and all traces of the key from the system?

Thanks!

Edit: link to the question I referenced: https://feddit.de/post/6735667

  • aard@kyu.deEnglish
    2·
    1 year ago

    I have a soft spot for AMD for sticking with the FOSS community to an extent and for their affirmative action towards open silicon initialisation with OpenSIL.

    I’m quite happy with having proper graphics cards again thanks to AMD working with their open source driver - and also looking forward to OpenSIL. Though there’s still the problem with the PSP in their CPUs.

    If you go through my posts, just the other day I was asking if the T440p was the last Thinkpad I could put Coreboot on (the answer is yes)

    Did you checkout heads? That’s what I’m using on my x230 - seems to be currently the most sensible choice for portable hardware.

    I will be employing Faraday cages and metal shielding liberally around my electronics

    Also make sure to shield cables. There’s not much public research into passive RF, but from the few people who looked into that we can say that the situation is bad, and the bad guys probably can do a lot of bad things (most likely both display signals and keystrokes from a USB or PS/2 keyboards can be recovered reasonably well from some distance by just analysing the RF sent by the cables)

    Unless we’re talking about undisclosed exploits in Android, removing Google and most other proprietary applications should do the trick

    Pretty much all phones sold in a bit over a decade no longer have a separate baseband. With a unified memory architecture you possibly have a remotely exploitable (remember, baseband) access to the OS memory, if you manage to bypass memory restrictions - in which case none of the mitigations in the OS will help you as it’s just not aware of you being there. While this is a pretty complex attack it unfortunately has been proven in a few cases to be possible. I don’t keep very important stuff on my phone - I don’t consider it trustworthy.

    Thank you for bringing across the point of spying using an accelerometer (I’m interested in how that would work, could you point me towards what I should look for?)

    Seems research about being able to recover a phone password/pin by using the phones accelerometer is shadowing search results - I’m pretty sure I’ve seen a paper about a phones accelerometer being used to reconstruct key strokes of a keyboard on the same table a few years ago - pretty much same idea as recovering the keystrokes via sound.

    Also note that things like hard disks contain their own embedded computer, and in some cases contain an accelerometer. They also have DMA access…