Hall of Fame/HallofFameCDROM.cdr/other/pgp10.lzh/SETUP.DOC

Text File | 1991-06-05 | 6KB | 148 lines

     Pretty Good Privacy version 1.0 - Installation Guide



How to Install PGP
==================

First, PGP only runs on MSDOS machines at this time; if you have
something else, you will need to be patient (or get the source and
help port the program to new environments; see the Copyleft notice).

PGP is distributed in a compressed archive format, which keeps all
the relevent files grouped together, and also saves disk space and
transmission time.  The current version, 1.0, is archived with the
PKZIP utility, and the PGP executable binary release system is in a
file named PGP10.ZIP.  This contains the executable program, the user
documentation, and a few keys and signatures.  There is also a second
file available containing the C and assembly source code, called
PGP10SRC.ZIP; unless you are a programmer interested in cryptography,
it is probably of little interest to you.  It may or may not be
available from the source from which you get PGP10.ZIP; if not, and
you want it, see the Licensing and Distribution section of the PGP
User's Guide.

You will need PKUNZIP version 1.1 or later to uncompress and split
the PGP10.ZIP archive file into individual files.  PKUNZIP is
shareware and is widely available on MSDOS machines (the only
machines on which PGP runs now anyway).

Create a directory for the PGP files.  For this description, let's
use the directory C:\PGP as an example, but you should substitute
your own disk and directory name if you use something different.
Type these commands to make the new directory:

   c:
   md \pgp
   cd \pgp

Uncompress the distribution file PGP10.ZIP to the directory.  For
this example, we will assume the file is on floppy drive A - if not,
substitute your own file location.

   pkunzip a:pgp10

The next step is recommended but not required.  It can help protect
you from a later virus infection or other destruction of the PGP
program.  Put a blank floppy on drive A (in this example) and copy
everything you just uncompressed onto it - then WRITE PROTECT the
floppy disk.  You can use that copy later (even without PKUNZIP
handy) to check to see if your copy of PGP is still trustworthy.

   copy *.* a: /v                    (with a blank floppy in A:)

Now write protect the floppy.

The next step is to validate the PGP program, using PGP itself.  This
will detect virus infections or any other tampering of the PGP
software.  For a full explanation of why this is important, read the
PGP User's Guide, with particular attention to the sections on
Vulnerablities, Viruses and Trojan Horses, Key Management, and Signed
Key Server Certificates.

If this self-validation test fails, you definitely have a problem -
either the program PGP.EXE or the PGP.CTX file have been damaged
(perhaps tampered with, perhaps virus infected, or perhaps just
corrupted in transit), or else the program is unmodified but does not
work on your hardware.  We know of no MSDOS machines on which it
doesn't work, but it is always possible.  If it does check out OK,
you have just run PGP successfully!  Unfortunately, this does not in
itself prove that the program is unmodified.  If someone deliberately
tampered with the program before you got it, they could have
substituted a bogus key for Philip Zimmermann and their own fake
signature file PGP.CTX as well, or modified the program to give false
assurances.  Your only real safeguard is to get your first copy of
PGP from a reliable source.  See the list of sources in the PGP
User's Guide.

But for now, let's assume that you have a good copy of PGP for the
following self test:

   pgp pgp.ctx pgp.exe

PGP should report a good signature from Philip R. Zimmermann on the
PGP.EXE executable program file, which indicates your copy of PGP
software has no virus infection and has not been tampered with.

Any time that you want to reassure yourself that PGP has not been
corrupted by virus or by any other means, you can repeat this test
using the write protected floppy disk version (don't remove the write
protect!), thusly:

   SET PGPPATH=A:\
   a:pgp a:pgp.ctx pgp.exe


Setting the Environment
-----------------------

Next, you can set an MSDOS "environment variable" to let PGP know
where to find its special files, in case you use it from other than
the default PGP directory.  Use your favorite text editor to add the
following lines to your AUTOEXEC.BAT file (usually on your C: drive):

   SET PGPPATH=C:\PGP
   SET PATH=C:\PGP;%PATH%

Substitute your own directory name if different from "C:\PGP".


Generating Your First Key
-------------------------

One of the first things you will want to do to really use PGP (other
than to test itself) is to generate your own key.  This is described
in more detail in the "RSA Key Generation" section of PGP User's
Guide.  Remember that your key becomes something like your written
signature or your bank card code number or even a house key - keep it
secret and keep it secure!  Use a good, unguessable pass phrase and
remember it.  Right after you generate a key, put it on your key
rings and copy your secret keyring (KEYRING.SEC) to a blank floppy
and write protect the floppy.


Validating Future Releases of PGP
---------------------------------

Now we get to an important new feature of this technology.  Once you
have a good copy of this first release, you can use it to check the
validity of future releases!  We will use the same key to sign future
releases.  If you acquire something which claims to be PGP 1.1 (or
2.3 or whatever), be sure to check it using the write protected
PGP.EXE and KEYRING.PUB on the write protected floppy.  Say you just
got PGP11.ZIP and uncompressed it to directory C:\PGPNEW.  The
directory should now contain a new PGP.EXE and a PGP.CTX, among
other files.  Put the write protected floppy in drive A and enter:

   SET PGPPATH=A:\
   a:pgp pgp.ctx pgp.exe

If the write protected copy of PGP from the floppy, using the
KEYRING.PUB from the same floppy, validates the new version of PGP,
you can be pretty sure that it really is from me and has not been
tampered with.  (There could still be a problem if a virus which was
specifically targeted at PGP was already resident in your computer
memory when you did the test; you might want to reboot first and use
any anti-virus programs you trust first).