			The PGPsendmail/Unix Suite

		    Richard Gooch  rgooch@atnf.csiro.au


1)  What is it?

  The PGPsendmail/Unix Suite provides for automatic encryption and
decryption of Email messages, using PGP. The two main programmes are
PGPsendmail and PGPdaemon. There is also a third programme:
sendpgppass  used for communicating your passphrase to PGPdaemon.

2)  PGPsendmail

  PGPsendmail is a drop-in wrapper for the standard  sendmail
programme which resides as  /usr/lib/sendmail  on most Unix systems.
It allows the automatic encryption of outgoing messages by using the
recipient's PGP public keys. It does *not* provide for automatic
decryption of incoming messages: such a feature would necessarily
involve compromising your passphrase.

  PGPsendmail may be installed by your system administrator, allowing
everyone on the system to reap the benefits. Alternatively, it may be
privately installed by ordinary users. For the latter case, your
mailing software (eg. EMACS ViewMail, elm, UCBmail, etc.) must be told
to use PGPsendmail to deliver mail rather than the regular  sendmail
programme.

  Read the installation instructions before attempting to install. You
have been warned.

  There is another package: PGPSendmail/AmigaOS which does much
the same thing as PGPsendmail except it runs on AmigaOS. See the
section on getting PGPsendmail/Unix for details of where to get
it.

3)  PGPdaemon

  PGPdaemon is a daemon, run by the user, which provides for the
automatic signing and decryption of messages. It will also
periodically read the users' incoming mail spool directory and will
move the contents to another spool file, decrypting any messages that
it can.
In order to perform these operations, PGPdaemon requires access to the
users' passphrase and secret key. On a secure system, this should not
pose a problem. On a public system, this may be a cause of concern.
However, if you are concerned about PGPdaemon compromising your PGP
secret key and passphrase, you should also be concerned about these
being compromised even if you are using PGP in the conventional way.
PGPdaemon is written based on the approach that if you compromise your
secret key and passphrase by using them on a public system, you may as
well make it as convenient as possible.
Since PGPdaemon does not require the passphrase to be stored in an
environment variable, it should be considerably more secure than
automatic decryption methods which use that technique.
PGPdaemon make a good effort to avoid being compromised. Future
versions will provide various features to detect and thwart attempts
at tampering.

4)  sendpgppass

  A small programme which reads the passphrase from the user and
transmits it to PGPdaemon.

5)  More information

  See the manual pages and the files in the  doc  directory. The
doc/COMPILING  file gives hints for compiling. Well worth reading.

6)  Getting PGPsendmail/Unix

  The PGPsendmail/Unix Suite is available for anonymous ftp from:
ftp.atnf.csiro.au: pub/people/rgooch
ftp.dhp.com: pub/crypto/pgp/PGPsendmail

  PGPSendmail/AmigaOS is maintained by Peter Simons
(simons@peti.gun.de). It is available for anonymous
ftp from any Aminet host in:  pub/aminet/util/crypt
The main Aminet site is:  wuarchive.wustl.edu


  There are two files in the PGPsendmail/Unix distribution:
   PGPsendmail-vN.n.tar.gz   	a tar file compressed with gzip which contains
				all source code for PGPsendmail version N.n
   PGPsendmail-vN.n.tar.gz.sig	my signature on above

  Inside the compressed tar file, you will find a file:  pubkey-rgooch.asc
which contains my public keys:
    my work key, for most everything
    my home key, for really earth-shattering, die after reading stuff (funny,
  no-one has ever used this key: guess I'm not important enough:-)

  My public key is also available by issuing the following incantation:
    finger rgooch@venice.atnf.csiro.au

****

7)  Copyright and Disclaimer

  PGPsendmail/Unix and associated software is covered by the GNU
General Public License. See the files:  COPYING  and  COPYING.LIB  for
more details.

[CYA mode ON]
  An important extract, the disclaimer:

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.
[CYA mode OFF]
