From: Superuser <visgraph!root>
Date: Tue, 31 Aug 93 08:39:02 PDT
To: cypherpunks@toad.com
Subject: Re: Help/Advice requested (fwd)
Message-ID: <199308311534.AA04994@visgraph.uucp>
MIME-Version: 1.0
Content-Type: text/plain


Through e-mail, gnu@toad.com writes:
| 
| > Anyone have some ideas about how to implement such a beast?
| 
| First you have to tell us what it's supposed to do.
[ ... ]

	Sorry, I had assumed that people would know about registration schemes
	here.

	By the use of a (perhaps complex) algorithm, generate serial numbers
	that would be entered by the registering user which would effectively
	'register' the program.  There would be a routine in the executable
	that could detect a valid serial number and act accordingly.

	The algorithm to do this should be well-hidden into the code, as
	to discourage simple hacking and alteration...

	There are a wealth of schemes out there.  For example, SCO UNIX uses
	a (albeit weird) scheme that involves a serial number and activation
	key which actually decrypts the executable (not what I want to do,
	really).  INFORMIX uses a scheme that brands the executable with a
	serial number (very interesting).

	I thought of having an external program that would brand the executable
	with a serial number and perhaps some other hidden information in
	reserved spaces.

	Something like the program mentioned below would be effective in hiding
	the code.

	What else do you need to know?

| > have run something like PKLITE on your executable) encapsulates the
| > EXE file, encrypted, with CRC checks and debugger traps.
| 
| Fine, it uses encryption and CRC and debug traps.  Now, to what purpose?
| What's the objective?  What's the goal?  Why?
[ ... ]

	Here's a README from the distribution...

Protect! EXE/COM 3.1 encrypt and still run .EXE's       Registration $ 25.00
SDN_UTIL AUG93 PROTECT EXE COM CRC SECURE ENCRYPT SCRAMBLE
FILES: PrExCm31.SDN

Author: Jeremy Lilley

        Protect! EXE/COM  is a  powerful  EXE/COM  protection utility which
        thoroughly encrypts  any EXE or  COM file  but still  allows  it to
        be run. And, files protected by  it make a full CRC INTEGRITY CHECK
        every time they are run.

        This NEW version fixes many bugs found in previous versions of this
        program such as an infamous screen bug in v.3.0. Additions are made
        to make this program to prevent  CRACKING, REVERSE ENGINEERING, and
        MODIFICATION even more.

        This program is one of the most powerful and cost-effecive solutions
        to problems with your programs' being modified by malicious hackers.
        With every other form of file security being nullified, Protect! has
        been renewed and can  now secure your  programs more than ever. What
        would you do  if somebody  were to  add a  TROJAN or 'MODIFY'  a few
        screens to a program of yours ?  Protect! can make this circumstance
        extremely unlikely for only $25. If a problem is detected, a message
        of your choice can be outputted to the user to tell the user exactly
        what to do.  Instead of burying your head in the sand,  get Protect!
        to protect your programming and software investment.


Requirements: DOS 2.0 or higher, IBM or compatible PC, 256k RAM, & any
              executable file  compression  utility  such  as   LZEXE,
              PKLite, Compack, Diet, or another program for compressing
              EXE files before they are scrambled and protected.



          [ .SDA Format is (c)Copyright 1993 The SDN Project ]
          [  SDN Authors-Only Info Line is 203-634-0370 USA  ]

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If you need more information, I can give you the author's email address...