Re: Software protection scheme may boost new game sales

[Sunder]

On Mon, 13 Oct 2003, Jerrold Leichter wrote:

> different forms.  It's been broken repeatedly.  The one advantage they have
> this time around is that CD readers - and, even more, DVD readers; there is
> mention of applying the same trick to DVD's - is, compared to the floppy
> readers of yesteryear, sealed boxes.  It's considerably harder to get at the
> raw datastream and play games.  Of course, this cuts both ways - there are
> limits to what the guys writing the protection code can do, too.

>From the POV of a coder for this kind of protection, there's probably some
API you can use to get at the error correction info somewhere -- or you
can use timing info... i.e. ask for a bad sector, and see how long it
takes to return the sector vs one that's supposed to be good...  

You can't stray too far from published API's, since if you do, you'll
potentially break your game when future OS's, patches, service packs,
hotfixes, or devices come out...  I.E. if you don't support anything but
IDE CDROM's, will you fuck users that use SATA, scsi, FireWire, or USB
cdroms? etc...  What happens under Windblows 2005?  Does your business
model say that they can't play on future OS's/hardware?  You won't be in
business very long if you do that.


>From the POV of the cracker, you can write a driver that looks like a
CDROM driver to the OS, and run the game.  It would act as a proxy to the
real CDROM, but also log any unusual activity (errors, odd timing,
etc...)  So then, the cracker can write a second virtual cdrom driver, one
that passes through the usual data off the CDR copy, but for those
"unusual" sectors that it captured earlier, replay the action.

Might even want to do this with two machines so you lessen the chance that
the game will find the original CD and ignore the virtual. :)

Of course the game could somehow figure out if a CD is virtual - by
getting driver information?  But if you're sneaky enough you can make your
virtual CDROM driver look like a second IDE controller, etc.. (see above
about SATA, USB, etc...)


Doing a search on google for "virtual cdrom" I see quite a few such
beasts...  It's possible one of these even has source code, but I don't
much care to bother searching further as I've no interested in this except
from the theoretical. :)

(In terms of things like Linux/*BSD you don't need no stinkin' driver, you
can directly mount an ISO file, but you could very easily write a block
device driver that added the errors/delays or whatever these things depend
on.)


That said, the scheme isn't without merit provided that it tells the luser
that he should purchase a real one maybe after it stops working pop up
an ad and say "Now that you've played your friend's copy, and saw the
demo, you can continue if you buy the full version..."

I seem to remember lots of old Macintosh software doing this.  You were
allowed and even encouraged to copy the floppy it came on and give it to
your friends.  When your friend installed the software, it would ask for
the serial #, (which you weren't supposed to give out.)

At that point, it would go into demo mode and run for a week, or two, and
then refuse to run.  So if your friend wanted the cool program you
recommended, they'd buy their own copy.  I'm not sure how successful that
was, but I'm assuming it did quite well...

The difference between that and this, is that if you put the floppy on
your fridge door with a magnet, you could always get your backup (or ask
your friend for her copy.)  With this, even if you have a legally
purchased copy, one or two scratches and it's literraly "Game Over Man!"  

:)


--Kaos-Keraunos-Kybernetos---
 + ^ + :25Kliters anthrax, 38K liters botulinum toxin, 500 tons of   /|\
  \|/  :sarin, mustard and VX gas, mobile bio-weapons labs, nukular /\|/\
<--*-->:weapons.. Reasons for war on Iraq - GWB 2003-01-28 speech.  \/|\/
  /|\  :Found to date: 0.  Cost of war: $800,000,000,000 USD.\|/
 + v + :   The look on Sadam's face - priceless!   
[EMAIL PROTECTED] http://www.sunder.net 

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Re: Software protection scheme may boost new game sales

[Jerrold Leichter]

| I've not read the said article just yet, but from that direct quote "as
| the copy degrades..." I can already see the trouble with this scheme:
| their copy protection already fails them.  They allow copies to be made
| and rely on the fact that the CDR or whatever media, will eventually
| degrade, because their "code looks like scratches..."  Rggghtt.
You should read the article - the quote is misleading.  What they are doing is
writing some "bad data" at pre-defined points on the CD.  The program looks
for this and fails if it finds "good" data.

However ... I agree with your other points.  This idea is old, in many
different forms.  It's been broken repeatedly.  The one advantage they have
this time around is that CD readers - and, even more, DVD readers; there is
mention of applying the same trick to DVD's - is, compared to the floppy
readers of yesteryear, sealed boxes.  It's considerably harder to get at the
raw datastream and play games.  Of course, this cuts both ways - there are
limits to what the guys writing the protection code can do, too.

The real "new idea" here has nothing to do with how they *detect* a copy - it's
what they *do* when they detect it.  Rather than simply shut the game down,
the degrade it over time.  Guns slowly stop shooting straight, for example.
In the case of DVD's, the player works fine - but stops working right at some
peak point.  Just like the guy on the corner announcing "first hit's free",
they aim to suck you in, then have you running out to get a legit copy to
save your character's ass - or find out how "The One" really lives through
it all.  This will probably work with a good fraction of the population.

Actually, this is a clever play on the comment from music sharers that they
get a free copy of a song, then buy the CD if they like the stuff.  In effect,
what they are trying to do is make it easy to make "teasers" out of their
stuff.  There will be tons of people copying the stuff in an unsophisticated
way - and only a few who will *really* break it.  Most people will have no
quick way to tell whether they are getting a good or a bad copy.  And every
bad copy has a reasonable chance of actually producing a sale

-- Jerry

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Re: Software protection scheme may boost new game sales

[Sunder]

Yawn...  This is no different than any of the copy protection schemes
employed in the 1980's on then popular home computers such as the
commodore 64.  

Hindsight is 20/20 and recalls, all of these were broken within weeks if
not months.  "Nibbler" copiers and other programs were quickly built that
allowed the breaking of all of these systems.  All sorts of "error"
sectors, duplicate tracks, half tracks, extra tracks, extra sectors,
non-standard sized sectors, tracks written at different speeds, erroneous
checksums, hidden data, and other sorts of weird bits were employed.  All
were broken.  None survived the ages.

In the end, the companies that employed copy protection only managed to
piss off customers who lost their only copy of the software, and created a
market for the copiers and crackers.  The crackers won, the software
companies lost.  

Few of the companies of that era are still in business today.  CEO's,
Vulture Capitalists, and others who have an interest in such schemes would
do well to invest some time in learning about that time, and the results,
for their investments, and dollars will go the same way... the way of the
brontosaurus, the trilobite, and the dodo.

Let them try, if they wish to burn their money.  As far as I'm concerned,
I'll vote with my wallet as usual and only run open source, free software.  
If the moronic kids at whom these titles are aimed have the $50-$70 per
title to waste on self destructing, flavor of the month games, they are
certainly free to spend that money to their heart's desire.


Not a dime from my wallet will wind up in their pockets - except perhaps
indirectly:  the next time I buy my next burger, "no, I don't want fries
with that, no, I don't want to supersize it," my $5 eventually makes a
small contribution to the salary of the burger flipper, which in turn is
applied to the purchase of said game.  :)



I've not read the said article just yet, but from that direct quote "as
the copy degrades..." I can already see the trouble with this scheme:
their copy protection already fails them.  They allow copies to be made
and rely on the fact that the CDR or whatever media, will eventually
degrade, because their "code looks like scratches..."  Rggghtt.

If you can make one copy, you can make many, and you can certainly store
the ISO in compressed form on a normal CD to make more copies
later.   CDR's are what? $0.20@ these days?

Hell, you can even get one of those virtual CDROM programs to mount the
CD's as if they were CD's, and store the ISO on a hard drive, or DVD-R
instead. Hard drives are already in the 250-500GB range these days.  So
their scheme is already flawed and doomed from the start.

It seems to me that people that engage in treating their customers like
theives to begin with lack a vital ingredient for making money: common
sense.


--Kaos-Keraunos-Kybernetos---
 + ^ + :25Kliters anthrax, 38K liters botulinum toxin, 500 tons of   /|\
  \|/  :sarin, mustard and VX gas, mobile bio-weapons labs, nukular /\|/\
<--*-->:weapons.. Reasons for war on Iraq - GWB 2003-01-28 speech.  \/|\/
  /|\  :Found to date: 0.  Cost of war: $800,000,000,000 USD.\|/
 + v + :   The look on Sadam's face - priceless!   
[EMAIL PROTECTED] http://www.sunder.net 

On Sat, 11 Oct 2003, Steve Schear wrote:

> Companies are using a new software protection system, called Fade, to
> protect their intellectual property from software thieves. Fade is being
> introduced by Macrovision, which specializes in digital rights management,
> and the British games developer Codemasters. What the program does is make
> unauthorized copies of games slowly degrade, by exploiting the systems for
> error correction that computers use to cope with CD-ROMs or DVDs that have
> become scratched. Software protected by Fade contains fragments of
> "subversive" code designed to seem like scratches, which are then arranged
> on the disc in a pattern that will be used to prevent copying. Bruce
> Everiss of Codemasters says, "The beauty of this is that the degrading copy
> becomes a sales promotion tool. People go out and buy an original version."
> (New Scientist 10 Oct 2003)
> 
> 

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