From: Eli Brandt <ebrandt@jarthur.Claremont.EDU>
Date: Wed, 25 Nov 92 10:30:40 PST
To: cypherpunks@toad.com
Subject: PGP on local machine (was Re: MacPGP)
In-Reply-To: <199211251002.AA24840@well.sf.ca.us>
Message-ID: <9211251830.AA13482@toad.com>
MIME-Version: 1.0
Content-Type: text/plain


> From: George A. Gleason <gg@well.sf.ca.us>
> Seems to me we need it for encryption as well...  For instance, telecom
> software which allows you to back out into a screen editor where you write
> something and then encrypt it, and then get back to telecom and transmit the
> ciphertext directly.

The following would require customization on both ends, but seems doable:

You compose the message, using emacs or some other Turing-complete editor.
You hit the "PGPify" key [sequence].
emacs echoes a special START string
The local comm program recognizes it and goes into "capture" mode.
emacs blats the plaintext to stdout, where it is captured.
emacs echoes a STOP string.
The comm program sees this, stops capturing, shells to DOS, and runs PGP.
emacs kills the original text block.
(emacs command ends)
The comm program shoves the cyphertext into the upload stream.
(comm macro reverts to lurk mode)
You send the message.

All of this, I think, could be implemented with available programs.
Kermit won't hack it on the local end, so maybe I'll switch to
Telemate.  This protocol would require a clean line or EC modem; is
this a problem?

It might be a better move to write a [shell, Perl] script that's a
drop-in replacement for Unix pgp: it goes through the whole protocol
above, and looks to the outside world as if it had done the work
itself.  People have written emacs macros (I think) to make this
work with mail; it could also be used as a unix-pgp replacement in
other places.

It might be nice if the plaintext were not echoed to the screen while
being transferred, too.

   Eli   ebrandt@jarthur.claremont.edu