From: Dave Chassin
Subject: Protecting AutoLISP Programs
Date:
Message-ID: <1005@rpics.RPI.EDU>
We are in the process of developing a very lengthly program
in AutoLISP. We are interested in marketing said program as
a third party package for AutoCAD systems. The issue has been
raised (inevitably) of protecting software. I'm against it in
principle but many of the techniques we use are themselves
copyrighted by some of the people working on the project. I
know it may seem strange but I was wondering if this would
work as a code protection system:
Take every atom that is used and that is not an
AutoLISP function and substitute it and all other
occurences of it with a garbled atom.
This assumes you don't do any wild symbolic stuff and all that.
We are not so much interested in preventing proliferation as
keepings the techniques, tricks, and ideas private.
Now, since no system is hacker proof, how would you rate this
trick on a scale of 0 (no protection) to 10 (NSA)?
Dave Chassin
PS: I don't like any kind of protection. My opinion is that
ideas and rumors are very alike. They only get better with
proliferation. However judging by the amount of debate on the
subject nowadays I must be in the minority. Or am I?
_____________________
David P. Chassin
Rensselaer Polytechnic Institute |
School of Architecture __+__
Troy, NY 12181 / _ \
USA | | | |
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It can be done. It has been done. Autodesk has such a program,
called "The Kelvinator," available to authorized developers. An
encryption facility for AutoLISP programs and menus is also available.
The protection provided by using both encryption and Kelvination
is not airtight, but is probably comparable to that provided by shipping
executable rather than source programs.
John Nagle