5 ms·

Determined attacker will have your disk physically copied before attempting anything, so "delete all my files" won't work. For such scenarios plausible deniabi

Determined attacker will have your disk physically copied before attempting anything, so "delete all my files" won't work. For such scenarios plausible deniability is what you want. Ideally, you need a whole parallel system which plausibly appears to attackers as if it is legitimately authorized/decrypted. StegFS is an example building block for such systems. If they know you work on breeding war rabbits, you better have some fake files with records of failed attempts to breed war rabbits and your real files hidden in deeper layers.

labcomputer 5y ago
Right, but that’s sort of the reason some OSes like MacOS use a hardware security module to store the key used for encrypting the disk contents. Your adversary can make as many copies of the disk as they want, but they need the HSM (which is, by design, hard to clone) to read the plaintext. An HSM can even enforce policies like rate limiting brute force attempts and/or erasing itself after too many attempts. It could even support a duress password which immediately erases the keys. Without the ability to clone the HSM, the attacker doesn’t get a “second chance” if they attempt to use the duress password.
- RegnisGnaw 5y ago
  At that point, the attacker will re-aim the wrench at your head instead of your body.
Retric 5y ago
Determined attacker might be a mugger trying to get your ATM pin. Assuming they will always have access to the underlying system being protected is missing out on a huge range of security issues.
- bombcar 5y ago
  ATM is an example where it might match the threat level - a pin that reveals an account with $450 or so in it instead of the real accounts.
tomatotomato37 5y ago
I feel a whole parallel system is very risky due to the large service area you have to emulate; screwing something up like Last Modified dates or system updates may reveal you never used that system since 2012. I would rather hide anything risky in an area where high-entropy binary blobs wouldn't appear unusual; the output folder of a hobby data compresser project wouldn't be a bad choice.

labcomputer 5y ago

Right, but that’s sort of the reason some OSes like MacOS use a hardware security module to store the key used for encrypting the disk contents. Your adversary can make as many copies of the disk as they want, but they need the HSM (which is, by design, hard to clone) to read the plaintext. An HSM can even enforce policies like rate limiting brute force attempts and/or erasing itself after too many attempts. It could even support a duress password which immediately erases the keys. Without the ability to clone the HSM, the attacker doesn’t get a “second chance” if they attempt to use the duress password.

RegnisGnaw 5y ago
At that point, the attacker will re-aim the wrench at your head instead of your body.

Retric 5y ago

Determined attacker might be a mugger trying to get your ATM pin. Assuming they will always have access to the underlying system being protected is missing out on a huge range of security issues.

bombcar 5y ago
ATM is an example where it might match the threat level - a pin that reveals an account with $450 or so in it instead of the real accounts.

tomatotomato37 5y ago

I feel a whole parallel system is very risky due to the large service area you have to emulate; screwing something up like Last Modified dates or system updates may reveal you never used that system since 2012. I would rather hide anything risky in an area where high-entropy binary blobs wouldn't appear unusual; the output folder of a hobby data compresser project wouldn't be a bad choice.