On Line
Rob Hays
July 1995
	With increasing frequency, both business and personal
communication is being handled via e-mail. With the increased
flexibility and convenience comes increased concern for
security. This month we will take a look at a Pretty Good
solution to this problem.

Pretty Good Privacy

	Suppose you received an e-mail message from your boss
telling you that you had been fired. The message says not to
bother coming to work tomorrow. All of your possessions would be
sent to you. How would you know if the message was genuine? Most
e-mail has a header at the top of the message detailing who sent
it, when, and even the route the message took to get to you. But
this header information can be altered or falsified. When it
comes to electronic messages, just because it walks like a duck,
and quacks like a duck, does not necessarily make it a duck.
	Turn the problem around. Suppose you are the boss and want
to send one of your employees a message that you don't want
anyone else to be able to read. Or suppose you want to send a
plain text message, the authenticity of which every reader would
be able to verify with certainty. Obviously some sort of
encryption could solve the first two problems, but how about the
last?
	The solution to all of these problems, and more, is Pretty
Good Privacy, from Phil's Pretty Good Software. PGP is a public-
key encryption program. Public-key is a security concept that is
deceptively simple. Everyone who uses the system has two keys, a
private key and a public key. The public key is published as
widely as possible, so as many people as possible either have it,
or have easy access to it. Each key can unlock the code produced
by the other, but the private key cannot be re-created by the
public one.
	When you use your private key to encode a piece of text,
that text can only be read by yourself with the same private key
you used to encode it, or by someone who uses your public key.
The fact that it was YOUR public key that could decode the text,
proves it was you who encoded it originally. Conversely, someone
could use your public key to encode a message that could only be
decoded by your secret private key.
	The verifiable plain-text message is handled by another
feature of PGP. This allows you to add a block of ASCII
characters to the end of a message. This block of characters is
generated based not only on your private key, but message
content and other factors. This means that if someone made a
change to your message, the signature block at the end would no
longer match, and the message would not be verified. PGP can
perform many other functions, and data files can be protected as
well as text files. In fact, the help file lists 35 functions,
and the entire documentation directory is more than 300K.
	PGP is a multi-platform package with versions for IBM,
Unix, and other systems as well as the Amiga, and was written by
a group headed by Phillip Zimmerman. The program is entirely
command-line oriented, but commands are relatively simple and are
straight-forwardly explained.
	The first step in using the program is to generate the
public and private keys that you will use. Three levels of
security are offered when you generate a set of keys, with a
trade off between speed and security. The program tells you to
type a string of random characters, and uses these along with
timing between keystrokes to generate a large random number.
This number then is used by the program to create your unique
keys.
	This is a program that the US government does not like.
Quite simply, they would prefer that everyone use the encryption
method that the National Security Agency developed, called
Clipper. The problem is, the government would keep a copy of your
private Clipper key on file, ready to decode your communications
if they decided they needed to. One of the restrictions placed on
PGP is that you can not use it or export it outside the US or
Canada, the reason being that the Government classifies the data
encryption algorithms the same as munitions when it comes to
export licenses. All of this and much more is explained in the
doc files included with the program archive.
	Pretty Good Privacy is at version 2.6.2, and is freeware.
There are two versions of the program. One is suitable for any
Amiga processor, and the other is optimized for 68020 and higher
processors. At 265,856 bytes, a 2400 bps modem will let you start
feeling more secure in about 22 minutes.

FileRequester

	Are you often annoyed by programs that use their own file
requesters instead of the one provided by Workbench 2.0 and
above? Even top-of-the-line software such as DPaint fails to make
use of the Amiga requester. FileRequester 1.0 (figure 1) from
Carsten Orthbandt remedies this annoyance.
	When the program is active, clicking in just about any non-
standard requester and pressing a hot-key combination will bring
up the standard asl requester. Select the desired file in the
usual way, and when you click on the OK gadget or press return,
the path information is transferred to the programs requester for
action. While this requires a few extra steps, having the added
functionality of the asl requester can more than make up for the
extra work.
	FileRequester is freeware, and the archive is only 8832
bytes, and can be yours in less than a minute.

ClipBoard Enhancer

	Any time you use the cut-and-paste function of your favorite
word processor, paint program, or any of a number of different
programs, you have made use of the Clipboard. This is a device
that temporarily holds the data until it can be pasted back into
a new location or different application. The problem is, once it
is pasted the data is deleted, so if you need a second copy you
have to cut-and-paste again. Some programs use their own buffers
to hold data for subsequent operations, but this data is not
available to other programs. The ClipBoard Enhancer (CBE) from
Anthony J.  Moringello (figure2) adds the same sort of history
found in the Shell to the Clipboard.
	Starting CBE opens a Listview gadget. Every time any program
uses the Clipboard, the information is maintained by CBE, and
displayed here. Actually, only the first few words of a text clip
will be displayed, but the entire clip can be viewed by clicking
on the View button. A notation describing the type of data is
also displayed. Text is not the only type of data that can be
held in the Clipboard, and if you clip a portion of a sound or
picture file, the data type and other information will be shown
in the CBE gadget. Pasting a clip is as simple as scrolling
through the list, selecting the clip you want, then using your
application's paste function in the usual manner.
	CBE is shareware, with a donation of $5 to $15 requested.
Registering the program will get you a key file that unlocks
additional functions not available in the unregistered version.
This key file concept is being used by more and more shareware
products, and allows a user to download later versions of the
program without having to re-register each time.
	CBE works on any Amiga with KickStart 2.04 or above. The
43,828 byte file contains AmigaGuide documentation, and a variety
of program icons. Less than four minutes are required to download
at 2400bps.

Where to look

	Because of a number of legal issues, PGP has evolved into
two functionally equivalent versions, one for use within North
America, and one for use everywhere else. The only place I found
the NA version was on GEnie, and the only way to download it is
to read and agree to a license agreement. To find PGP select #17
from the main Starship menu and follow the prompts. CompuServe
has the International version in the Applications Library in the
AmigaUser Forum as PGP26.LHA. This same version is available on
Portal under their number 4842.3.33.184. It is also available
from overseas Aminet mirrors in the subdirectory Util/Crypt.
	FileRequester is available on Portal under as number
4842.3.35.359. CIS users should look in the System Utilities
Library of AmgaTech Forum for FILERE.LHA. GEnie has this as file
#24900. For some reason Aminet keeps this in the Games/Gag
subdirectory.
	CBE is file #25705 on GEnie, and #4842.3.12.333 on Portal.
CIS has CBE.LHA in the same directory as Filre above. Aminet
users, look in the Util/Cdity subdirectory.

Who Ya Gonna Call?

	Here are some more Amiga BBS's you may want to check out.

NAME:			Fileworks
PHONE:			Line #1 (716) 377-0719
				Line #2 (716) 377-3695
SPEEDS SUPPORTED:	Line #1 up to 28.8kbps, Line #2, up to
				14.4kbps.
CONTACT:			Tom Waterstraat
				PO Box 842
				Fairport, NY  14450

NAME:			5th Generation BBS
PHONE:			(716) 425-7661
SPEEDS SUPPORTED:	up to 14.4kbps
CONTACT:			Brad Langton

NAME:			Graceful Boot
PHONE:			(716) 426-4779
SPEEDS SUPPORTED:	up to 14.4kbps
CONTACT:			Vitas Povilaitis

NAME:			Power Drive
PHONE:			(716) 458- 3412
SPEEDS SUPPORTED:	up to 14.4kbps
CONTACT:			Mike Cholach

NAME:			The Rat's Edge
PHONE:			(716) 225-8631
SPEEDS SUPPORTED:	up to 28.8kbps
CONTACT:			Neil Palumbo

Where To Find Me

		R.Hays5		on GEnie
		RHAYS		on Delphi
		72764,2066	on CompuServe
		Rob Hays		on Portal
	InterNet users, I now have a new email address:
rhays@ansel.intersource.com.

	For U.S.Mail:
		Rob Hays
		P.O.Box 194
		Bloomington, IN 47402
	Please include a SASE if you need a personal reply.

	If you run an Amiga specific BBS, send me the information
callers will need to access your system. Phone number(s), modem
speeds, software settings, etc. As a service to the Amiga
community I will include the information I receive in this column
from time to time. Send the info to any of my addresses above.

	That's all for now. See you online!
