File System Encryption

[Jason Burrell]

On Wed, 28 Aug 1996, Douglas R. Floyd wrote:

> > I may have to consider this approach. I'll have to look into Ian's system.
> > Does it pass muster with the crypto gods? (that's meant as a compliment
> > guys :)
> 
> It uses IDEA in a decently secure manner, as well as TDES.  You can also
> mount .au files as filesystems, and the data will be hidden in the sound
> file.
> 
> (Last place I remember Ian's loop.c and des patches for Linux was on
> ftp.csua.berkeley.edu, /pub/cypherpunks/<somewhere>)
> 

ftp.csua.berkeley.edu:/pub/cypherpunks/filesystems/linux. 

I haven't looked through the code very hard yet, but I do wonder how the
passphrase and such is stored. If I run losetup and setup
/root/stego_file.au as a filesystem on /dev/loop0, does that get stored
anywhere that isn't secure from non-root processes, or that is kept after
the filesystem is unmounted? I figure the passphrase definately is removed
as soon as the filesystem is unmounted, and that this is stored in
protected kernel memory.