Kayaker
January 30th, 2004, 02:25
Hi all,
Some may have heard of this protection before, apparently it's been around for a few years though there seem to be a few more recent press releases, I was just wondering if anyone has looked into the mechanics of it closer. There has been a small mention of it at club.cdfreaks.com and the Codemasters site for example, but little discussion on the details.
Here is a relatively recent article from
http://www.newscientist.com/news/news.jsp?id=ns99994248
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'Subversive' code could kill off software piracy
Software pirates who make illegal copies of a particular computer game are finding the games companies are coming up with a radical new anti-copying strategy.
Illegally copied games protected by the system work properly at first, but start to fall apart after the player has had just enough time to get hooked. As a result, the pirated discs actually encourage people to buy the genuine software, the developers say.
The new protection system, called Fade, is being introduced by Macrovision, a company in
Santa Clara, California, that specialises in digital rights management, and the British games developer Codemasters, based in Leamington Spa. It makes unauthorised copies of games slowly degrade, so that cars no long steer, guns cannot be aimed and footballs fly away into space. But by that time the player has become addicted to the game.
Fade exploits 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. The bogus scratches are arranged on the disc in a subtle pattern that the game's master program looks for. If it finds them, the game plays as usual.
When someone tries to copy the disc on a PC, however, the error-correcting routines built into the computer attempt to fix the bogus scratches. When the copied disc is played, the master program then cannot find the pattern it is looking for, so it knows the disc is a copy.
Promotion tool
What happens next turns the usual rules of software protection on their head. Instead of switching off the game and preventing it from playing at all, the master program begins to disable it. In the game Operation Flashpoint, which has been the proving ground for Fade, players soon find that their guns shoot off target and run out of bullets.
"The beauty of this is that the degrading copy becomes a sales promotion tool. People go out and buy an original version," claims Bruce Everiss of Codemasters.
The idea intrigues Alistair Kelman, an independent lawyer who specialises in copyright: "Fade is entirely in keeping with the spirit and great traditions of copyright." He points out that books tend to deteriorate with use and this prevents the secondhand market from competing with the market for new books. Why not the same for software?
Following its success with Operation Flashpoint, Codemasters is also using Fade with a new snooker game. Copies play normally for a while, but after a predetermined number of potshots, gravity is progressively turned off so the balls start behaving oddly and end up floating over the table.
Fade was devised by Richard Darling, who founded Codemasters 16 years ago, and has now been included in Macrovision's SafeDisc anti-piracy system. Next year, Macrovision plans to release a DVD movie protection system called SafeDVD, which will use a similar technique to make copied discs stop playing at a key point in the movie's plot.
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I had heard about this idea of "fake" CD scratches before, but to be able to create code which fools the systems natural error correction routines which compensate for scratched CDs sounds very intriguing. It also reflects a high degree of understanding of just what these correction mechanisms are and how they work. From the description this sounds like the mechanism is built into the OS as opposed to being part of the CD burners software?
Does anyone have any idea of how this is implemented or what the code that emulates a "scratch" might look like? CD protections aren't really my forte, my interest is more from the hardware/OS code/programming side of how the protection might work.
I like the "confuse-a-cracker" aspect of the protection too, instead of the "you have Softice installed therefore you are bad and I will not run at all" strategy
Kayaker
Some may have heard of this protection before, apparently it's been around for a few years though there seem to be a few more recent press releases, I was just wondering if anyone has looked into the mechanics of it closer. There has been a small mention of it at club.cdfreaks.com and the Codemasters site for example, but little discussion on the details.
Here is a relatively recent article from
http://www.newscientist.com/news/news.jsp?id=ns99994248
--------------------------------
'Subversive' code could kill off software piracy
Software pirates who make illegal copies of a particular computer game are finding the games companies are coming up with a radical new anti-copying strategy.
Illegally copied games protected by the system work properly at first, but start to fall apart after the player has had just enough time to get hooked. As a result, the pirated discs actually encourage people to buy the genuine software, the developers say.
The new protection system, called Fade, is being introduced by Macrovision, a company in
Santa Clara, California, that specialises in digital rights management, and the British games developer Codemasters, based in Leamington Spa. It makes unauthorised copies of games slowly degrade, so that cars no long steer, guns cannot be aimed and footballs fly away into space. But by that time the player has become addicted to the game.
Fade exploits 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. The bogus scratches are arranged on the disc in a subtle pattern that the game's master program looks for. If it finds them, the game plays as usual.
When someone tries to copy the disc on a PC, however, the error-correcting routines built into the computer attempt to fix the bogus scratches. When the copied disc is played, the master program then cannot find the pattern it is looking for, so it knows the disc is a copy.
Promotion tool
What happens next turns the usual rules of software protection on their head. Instead of switching off the game and preventing it from playing at all, the master program begins to disable it. In the game Operation Flashpoint, which has been the proving ground for Fade, players soon find that their guns shoot off target and run out of bullets.
"The beauty of this is that the degrading copy becomes a sales promotion tool. People go out and buy an original version," claims Bruce Everiss of Codemasters.
The idea intrigues Alistair Kelman, an independent lawyer who specialises in copyright: "Fade is entirely in keeping with the spirit and great traditions of copyright." He points out that books tend to deteriorate with use and this prevents the secondhand market from competing with the market for new books. Why not the same for software?
Following its success with Operation Flashpoint, Codemasters is also using Fade with a new snooker game. Copies play normally for a while, but after a predetermined number of potshots, gravity is progressively turned off so the balls start behaving oddly and end up floating over the table.
Fade was devised by Richard Darling, who founded Codemasters 16 years ago, and has now been included in Macrovision's SafeDisc anti-piracy system. Next year, Macrovision plans to release a DVD movie protection system called SafeDVD, which will use a similar technique to make copied discs stop playing at a key point in the movie's plot.
--------------------------
I had heard about this idea of "fake" CD scratches before, but to be able to create code which fools the systems natural error correction routines which compensate for scratched CDs sounds very intriguing. It also reflects a high degree of understanding of just what these correction mechanisms are and how they work. From the description this sounds like the mechanism is built into the OS as opposed to being part of the CD burners software?
Does anyone have any idea of how this is implemented or what the code that emulates a "scratch" might look like? CD protections aren't really my forte, my interest is more from the hardware/OS code/programming side of how the protection might work.
I like the "confuse-a-cracker" aspect of the protection too, instead of the "you have Softice installed therefore you are bad and I will not run at all" strategy
Kayaker