Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!uunet!stretch.cs.mun.ca!roger
From: roger@stretch.cs.mun.ca (Roger White)
Newsgroups: comp.sys.cbm
Subject: Re: Super Snap Shot Cart Detection??
Message-ID: <1990Sep25.182036.12210@stretch.cs.mun.ca>
Date: 25 Sep 90 18:20:36 GMT
References: <438@news.nd.edu> <-VJ%B=+@rpi.edu> <443@news.nd.edu>
Sender: roger@stretch.cs.mun.ca (Roger White)
Organization: CS Dept, Memorial University of Newfoundland
Lines: 52

In article <443@news.nd.edu> treesh@bach.helios.nd.edu writes:
>Anyways, you say that some of your software does not work with the cart plugged
>in, even if its in disabled mode right?  Thats just want Im looking for.  
>I am not trying to get my software to make use of the routines inside the
>cart, Im just trying to let my software know if the user has that cart 
>plugged in, so that if it does see it, it will erase itself!!

I have used Super Snapshot V3 for the past few years, and have tried all
available ways to find it in memory when it is disabled... you can't!
I don't know about the other carts but SS is invisible when totally
disabled (no "special" features activated).

> 
>The snapshot cartridge is the most amazing tool I have ever used, but my 
>problem with it is that its makes ANYONE a hacker.  Im trying to write code 
>that can not be vied in the montior, saved to the disk.
>
>I guess you would say Im sorta an anti-hacker!  Im more into the protection
>then the breaking of the protection!
>
>ctfm
> 

The only way I found to defeat the cartridge is to write some code to
the drive's memory early in the program (ideally in a "boot" program)
and then read this information once in a while within the main program.
The Snapshot cart only saves computer memory and not the drive's
memory, so when the program is "snapped" all that is saved is your
program in computer memory. When the "snap" is run later the drive's
memory will not be correct, your program can then do what it wishes
to the disk/computer. That is one advantage to having a "smart"
disk drive.

I feel that this is the best method to overcoming any memory dumping
technique. That is why you can't (normally) snapshot GEOS, it uses
a special fast loader installed in the drive that isn't copied over
to a snapshot. Thus locking up the computer when the snap is run.

Of course that (and any) technique will only stop the inexperienced,
anybody skilled in programming/de-protecting will be able to defeat
ANY protection scheme in time.


Roger.

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|                            | Roger White                                   |
| ...treat her like a lady,  | roger@stretch.mun.edu, roger@stretch.cs.mun.ca|
| and she will always bring  |-----------------------------------------------|
| you home -- Bones          | Memorial University of Newfoundland           |
|                            | St. John's, Newfoundland, Canada              |
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