3 ms·

I don't think this bothers me. The only reason that I do the disk encryption is so that I don't have to worry about people going through my laptop to steal tax

by tombert 3mo ago

I don't think this bothers me. The only reason that I do the disk encryption is so that I don't have to worry about people going through my laptop to steal tax documents and/or credit card stuff when I sell the laptop. I of course also wipe the laptop too, but I figure that if the data is encrypted at the drive level then there's very little risk of anyone being able to use some kind of forensics tool and recover data.

bluebarbet 3mo ago
Assuming the encryption key is strong, the wiping is theoretically redundant.
- tombert 3mo ago
  Agreed. It's also very low effort and as such I'm ok with the redundancy.
  - bluebarbet 3mo ago
    Indeed. Truth be told, I do it too.
- adrianmonk 3mo ago
  And assuming the crypto algorithm has no fundamental flaws, it's applied correctly, and the software implementation has no bugs. All of which are things people have on occasion believed to be true and found out later they were wrong about.
  - tombert 3mo ago
    I mean I don't think it's unfair to say that most of the battle-tested encryption is "uncrackable enough" for the consumer. If you're working for the NSA you need to worry about these things being cracked, obviously, but for the "I don't want a scammer to buy my laptop and get my social security number" situation, I think that you really can just assume that LUKS is uncrackable. That said, it takes like five minutes to boot a live Linux flash drive and run fdisk to delete the partitions and/or install Mint or something over the existing data, so I don't really see any reason not to do it, even if it's not strictly necessary.
chlorion 3mo ago
You can just wipe the luks header as a nice middle ground. Luks uses an anti-forensics algorithm that requires the entire volume key being available to unlock the disk at all (it combines the blocks of the key with some diffuse algorithm and xors stuff together to form the actual master key), so in theory you can just clear one sector of the volume key and the whole thing should be unrecoverable. What I mean is that if even one block of the key is missing you can't guess the rest easily.

by tombert 3mo ago

bluebarbet 3mo ago

Assuming the encryption key is strong, the wiping is theoretically redundant.

tombert 3mo ago
Agreed. It's also very low effort and as such I'm ok with the redundancy.
- bluebarbet 3mo ago
  Indeed. Truth be told, I do it too.
adrianmonk 3mo ago
And assuming the crypto algorithm has no fundamental flaws, it's applied correctly, and the software implementation has no bugs. All of which are things people have on occasion believed to be true and found out later they were wrong about.
- tombert 3mo ago
  I mean I don't think it's unfair to say that most of the battle-tested encryption is "uncrackable enough" for the consumer. If you're working for the NSA you need to worry about these things being cracked, obviously, but for the "I don't want a scammer to buy my laptop and get my social security number" situation, I think that you really can just assume that LUKS is uncrackable. That said, it takes like five minutes to boot a live Linux flash drive and run fdisk to delete the partitions and/or install Mint or something over the existing data, so I don't really see any reason not to do it, even if it's not strictly necessary.

chlorion 3mo ago

You can just wipe the luks header as a nice middle ground. Luks uses an anti-forensics algorithm that requires the entire volume key being available to unlock the disk at all (it combines the blocks of the key with some diffuse algorithm and xors stuff together to form the actual master key), so in theory you can just clear one sector of the volume key and the whole thing should be unrecoverable. What I mean is that if even one block of the key is missing you can't guess the rest easily.