From: Adam Shostack <adam@homeport.org>
Date: Sun, 24 Dec 95 09:14:09 PST
To: ericm@lne.com (Eric Murray)
Subject: Re: CFS and Linux
In-Reply-To: <199512241606.IAA04460@slack.lne.com>
Message-ID: <199512241717.MAA29337@homeport.org>
MIME-Version: 1.0
Content-Type: text


Eric Murray wrote:

| Where we're headed is mail filters with PGP imbedded (PGP 3 will
| make this much easier) that check incoming mail for a valid signature
| for certain PGP keyid/fingerprints and pass that mail along.
| Other mail that doesn't match gets tossed into a 'junk' folder
| or thrown away if you really don't want to talk to anyone that you
| don't already know.

I agree with the assesment of where we may be going, but the
technology is available now.  (Marshall Rose uses it; if you want to
get mail into his private mailbox, offer him some $ via imbedded FV
authorizations in the mail, and it goes into his inbox.  If he thinks
it was worth his time, he doesn't charge you.)

Anyway, the code is defeintely available now.  The back end is a
little kludgy, but it was needed for an auto ley retreival script.
This could easily be hacked to include a +pubring=$people line.  The
script gives you a keyid, which you can then use to filter on, ie:

:0BW
* -----BEGIN PGP
KEYID=|sender_unknown
# the sender unknown script is below

:0:
? [ $KEYID = (`cat .buddies`) ]
| /var/spool/mail/adam

:0e:
junk

#!/bin/sh
# unknown returns a keyid, exits 1 if the key is known
# $output is to get the exit status. Othierwise, this would be a one liner.
OUTPUT=`pgp -f +VERBOSE=0 +batchmode  -o /dev/null`
echo $OUTPUT | egrep -s 'not found in file'
EV=$? 
if [ $EV -eq 0 ]; then 
        echo $OUTPUT | awk '{print $6}' 
fi
exit $EV


-- 
"It is seldom that liberty of any kind is lost all at once."
					               -Hume