Re: [PATCH 0/5] ext4: RFC: Encryption
From: Pavel Machek <hidden>
Date: 2014-07-23 22:25:06
Also in:
linux-fsdevel
Hi!
This patchset proposes a method for encrypting in EXT4 data read and write paths. It's a proof-of-concept/prototype only right now. Outstanding issues: * While it seems to work well with complex tasks like a parallel kernel build, fsx is pretty good at reliably breaking it in its current form. I think it's trying to decrypt a page of all zeros when doing a mmap'd write after an falloc. I want to get feedback on the overall approach before I spend too much time bug-hunting. * It has not undergone a security audit/review. It isn't IND-CCA2 secure, and that's the goal. We need a way to store (at least) page-granular metadata.
http://en.wikipedia.org/wiki/Ciphertext_indistinguishability#Indistinguishability_under_chosen_ciphertext_attack.2Fadaptive_chosen_ciphertext_attack_.28IND-CCA1.2C_IND-CCA2.29 So .. you are trying to say that if I offer Disney ability to decrypt their chosen data, Disney may be able to prove I have their film encrypted elsewhere on the disk? Is it supposed to be IND-CPA secure? I.e. can Disney prove I have their film on my disk if I don't help them? IND-CCA1? Can I keep just a subtree (/home/pavel/.ssh) encrypted? Hmm, I might actually want to try this. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html