Subject: Re: CryptoGraphic Disk.
To: Urban Boquist <>
From: Roland Dowdeswell <>
List: tech-security
Date: 10/07/2002 11:06:32
On 1034002948 seconds since the Beginning of the UNIX epoch
Urban Boquist wrote:

>Great work! Thanks a lot!
>I have one question though. I used to use TCFS for a while, and one
>really nifty feature it had was that you could "remove" the encryption
>key from the kernel without unmounting the file system. Processes that
>tried to access the disk when the key was unavailable got read/write
>This was very handy on e.g. a travelling laptop, where you could use
>the /etc/apm scripts to simply remove the key automatically when
>suspending. Since you didn't need to unmount the file system you also
>didn't have to bother finding all processes inside the file system,
>kill emacs buffers visiting files inside it, etc. Once resumed you
>just re-entered the passphrase and everything was as before again.
>Would something like this be possible to add to cgd?

Yes, I was thinking about this but I haven't looked through the
code to see how easy it would be to actually do it.  I have a
sneaking suspicion that it may be a bit of a pain, but I'll get
back to you on it in a while.  (It's on the TODO list.)

    Roland Dowdeswell                      http://www.Imrryr.ORG/~elric/