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Physical Media Copy Protection By Wesley Wilson
Background n n n Software Developers are shying away from PC game development due to piracy According to CEO of ID Software Todd Hollenshead: "Piracy has pushed id as being multiplatform" Michael Capps of Epic Games says: ”PC Gaming is really falling apart. It killed us to make Unreal Tournament 3 cross-platform, but Epic had to do it to [recap its investment in the production costs]. " "The market that would buy a $600 video card knows how Bittorrent works. "
History of Physical Copy Protection n n During the 1980 s and 1990 s, computer games sold on audio cassette and floppy disks were usually protected with a user-interactive method that demanded the user to have the original package or a part of it, usually the manual. Copy protection was activated not at installation but every time the game was executed. Sometimes the copy protection code was needed not at launch, but at a later point in the game. This helped the gamer to experience the game (as a demo) and perhaps could convince him to buy it by the time the copy protection point was reached. The most common method: "What is the 13 th word on the 7 th line of page 22? " The lenslok system used a plastic prismatic device, shipped with the game, which was used to descramble a code displayed on screen.
Modern Physical Copy Protection n CD/DVD copy protection is a set of copy protection mechanisms that prevent users from copying compact discs (CDs) or DVDs. These mechanisms vary widely and include DRM, CD-checks, Dummy Files, illegal table of contents, over-sizing or over-burning the CD, physical errors, bad sectors and more. Many of these protection schemes rely on breaking compliance with the CD and DVD standards, leading to playback problems on some devices.
Secure. ROM n n n The Secu. ROM™ copy protection solution consists of two main components: A unique, uncopyable electronic keycode is added to each CDROM, DVD-ROM or CD-R during the glass mastering process. Unlike other copy control solutions on the market, the Secu. ROM keycode is fully within the CD/DVD-ROM specification, thereby ensuring the highest possible compatibility. An authentication mechanism verifies the unique Secu. ROM™ keycode and unlocks the encrypted software/application. The authentication mechanism is entirely key-less, meaning no serial numbers, stickers or artwork modification is required. The Secu. ROM™ authentication process is completely transparent to original disc users. If Secu. ROM™ verifies the disc is an original, the encrypted application starts normally. If Secu. ROM™ determines that the disc is a copy, the application terminates and a customizable error message is displayed. More than 200 Million discs protected since 1997
Secure. ROM DRM Options n n n Disc Based DRM Features Per default Secu. ROM™ checks for an original disc during every startup of an application. Feel free to customize your protection by selecting either (1) the one time only disc check or (2) periodic disc checks (every certain number of launches or days). Time Based DRM Features Define the start date and/or end date of your application. Depending on your product requirements, time based DRM features can checked either online (more secure) or offline (more convenient). Usage Based DRM Features Secu. ROM™ allows you to limit the functionality. Simply define the number of launches or days after executing the protected application the first time.
Safe. Disc n n Safe. Disc Advanced provides protection against disc copying by encrypting the program executable in an access control wrapper that requires authentication against the Safe. Disc signature to run. Safe. Disc v 3 uses a key to encrypt the main executable (EXE or DLL) and creates a corresponding digital signature which is added to the CD-ROM/DVD-ROM when they are replicated. The size of the digital signature varies from 3 to 20 MB depending how good the encryption must be. The authentication process takes about 10 to 20 seconds.
Safe. Disc • Safe. Disc installs its own Windows device driver to the user's computer, named secdrv. sys. In addition to enabling the copy protection, it grants ring 0 access to the running application. This is a potential security risk, since trojans and other malware could use the driver to obtain administrator access to the machine, even if the programs are running under a limited account. • Even worse is that most installers don't set the security configuration appropriately, allowing every user to let the driver configuration point at an arbitrarily chosen executable which (at the next reboot) is started with administrator privileges.
Star. Force • n n Star. Force is a controversial software copy prevention brand by the Russian developer Protection Technology. It is designed for Microsoft Windows. Its main strength lies in wrapping executable and DLL files using byte-code, interpreted through its own virtual machine Star. Force is believed to operate by measuring the physical angle between the first and last written sector on the CD. This hardware signature is identical on all copies pressed from the gold master but is currently difficult to reproduce when burning a duplicate CD. Star. Force also blocks the use of SCSI optical drives when IDE optical drives are present in the system, since most optical drive emulators currently work by simulating SCSI drives. Star. Force, however, will authenticate discs from a SCSI optical disc drive if there are no IDE optical disc drives installed in the system.
Star. Force n n Star. Force has received criticism for installing its own device driver onto computers. The Star. Force driver, which is installed along with the protected product or when the protected product is first run, is mostly not uninstalled along with the software and cannot be uninstalled using conventional methods To address this, Star. Force developers later published a removal tool to help untrained users remove the driver.
Problems With Star. Force n n n Has been known to cause optical drives to default to PIO mode The access control list of the drivers are set such that any user, including those without administrative rights, are allowed to change the association with the executable. Exploitation is simple: The user changes it to point at any arbitrarily chosen executable, which is executed with full system privileges on next reboot. On March 24, 2006, Christopher Spence filed a class action lawsuit on behalf of himself and other gamers against Ubisoft. As a result of that complaint, Ubisoft dropped Star. Force.
Sources n n n n n http: //www. shacknews. com/onearticle. x/46079 http: //www. macrovision. com/products/activereach_games/ safedisc/index. shtml http: //en. wikipedia. org/wiki/Safe. Disc http: //en. wikipedia. org/wiki/Ring_0 http: //en. wikipedia. org/wiki/Copy_protection http: //en. wikipedia. org/wiki/CD/DVD_copy_protection http: //www. securom. com/default. asp http: //en. wikipedia. org/wiki/Secu. ROM http: //www. macrovision. com/products/activereach_games/ safedisc/index. shtml http: //en. wikipedia. org/wiki/Safe. Disc