Re: Encryped Loop device possible feature to assimilate

Andrew E. Mileski (
Sun, 14 Dec 1997 15:49:02 -0500 (EST)

> While reading sci.crypt today, I came across the attached article. In it
> the person describes an encrypting block device that is partially immune
> to rubber hose cryptography..
> Basicly it stores multiple fses in the same space.. Each with differnt
> passwords.. You put your secret stuff in one segment, while putting
> plausable stuff (but not very incriminating, maby fake love letters to a
> misstress) in the others... If forced to revieal a password, you give them
> the password to the mock secret data.. They see the mock secret data..
> This is no new idea... But his ideas make it hard for an attacker to know
> that you really are hiding anything..

You can do this with my loop driver, which has an option for setting
the offset into the file, or when using stego by using the lowest bit
of odd bytes for real data, and even bytes for the phony stuff. The
stego method would be best, as it is less suspicious to have fs that
is smaller than the data file.

I'm working on getting my system ready for RedHat 5.0, so my last
patch is a little old, but it may still work on a new kernel:

Andrew E. Mileski