Steganography (`stealth') with GnuPG

[Frank Heckenbach]

David Shaw wrote:

> On Sun, Jul 22, 2001 at 01:28:07AM +0200, Frank Heckenbach wrote:
> > For PGP, there's a utility called `stealth' which strips off all
> > identifying header information to leave only the encrypted data in a
> > format suitable for steganographic use
> > (ftp://ftp.pgp.net/pub/pgp/utils/stealth/).
> > 
> > It doesn't seem to work with GnuPG encrypted files, however. Is
> > there a similar utility for GnuPG, or a way to make stealth work
> > with GnuPG?
> 
> Stealth only works with old-style pgp messages (pgp 2.6.x and
> friends).  It won't work with pgp 5 and up or openpgp (and hence gpg).
> It worked by stripping and juggling headers so that all that was left
> was raw encrypted bits which ideally would appear to be random.
> 
> You can probably use it with gpg if you generate pgp 2.6.x compatible
> messages (gpg --rfc1991 --cipher-algo idea --no-literal) using an old
> style v3 RSA key.
>
> Er, make that "gpg --rfc1991 --cipher-algo idea --compress-algo 1".
> Wrong cut-n-paste :)

I don't have the idea plugin, and AFAICS on the ftp srever, it's not
available currently (and I'd like to avoid a patented algorithm,
anyway). But thanks, anyway.

BTW, how hard would it be to write something like stealth for
OpenPGP (or is it not possible at all)? Though I won't have any time
for it now, maybe sometime later ...

Frank

-- 
Frank Heckenbach, frank@g-n-u.de
http://fjf.gnu.de/
PGP and GPG keys: http://fjf.gnu.de/plan