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Posted on 18-12-11, 11:21
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http://fabiensanglard.net/dreamcast_hacking/

It turned out that the scrambler was nothing more than "security through obscurity". The SDK contained a reverse-scrambler which transformed a valid executable into reverse-mashed-potatoes so it would be valid again when loaded and scrambled by the Dreamcast when booting from a CD-ROM.


As an aside, it looks like the ".gdi" metafile used for Dreamcast images is vastly more sane than the .cue metafile used by everything else these days. Another tally-mark for worse-is-better, I guess.

The ending of the words is ALMSIVI.
Posted on 18-12-11, 19:26
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it's funny how almost every anti-circumvention tech seems childishly simple/foolish in hindsight. It's rare to read about something and think "wow, that was really clever." Even the really clever ones seem to get beaten by nonsense like "shipped it with the damned keys still on it".
Posted on 18-12-12, 05:12
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I was pretty impressed with the Playstation anti-circumvention tech when I understood it, encoding a signal into the "track wobble" that CDs use to maintain constant linear velocity, but of course that wasn't the weak link in the chain. Somebody just recorded that signal and made a chip that played it back,

The ending of the words is ALMSIVI.
Posted on 18-12-12, 10:31
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And it doesn't really have to be perfect, just "good enough". The Dreamcast's likely would have been had the SDK not been literally stolen.

Honestly, the big mistake from a security stance was allowing the retail DC units to boot off of CDs at all. That they required hoops be leapt through to make it work was someone realizing it was a terrible idea, but not having authority enough to stop it from happening.

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Posted on 18-12-13, 00:58
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Why the hell Sega even wasted time bothering with the whole MIL-CD fiasco? Not only it costed them millions when hackers devised how to take advantage of that backdoor wide as a 747 for game piracy, nobody really bothered using it for actual music discs (aside of the eight lone titles ever released for the format)

All this debacle for yet another Japan-only feature that somehow got baked into almost every Dreamcast ever sold. How Sega did actually removed the support on late DCs? Updated firmware? (and if it's firmware-only, would it be feasible to either use older firmware from previous consoles, or patched firmware for restoring the support?)

Just wondering: what was so special about DiscJuggler that it was the only software suitable for burning Dreamcast rips to CD-Rs?

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Posted on 18-12-13, 08:01
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There are a few brilliantly simple copyright schemes though. One of the best ones I found out about was on the StarCraft CD (I think?) where the outer layer of the disk was circular and played the exact same message a certain number of times before jumping to another part of the disk.

This of course confounded those pirates for years, because most CD-ROM media burns in an inward spiral. This then caused the software image to simply write the same repeatable garbage pattern to the ISO file, making it impossible to play back.

Clever, clever... And easily defeated once you know what to look for! :)
Posted on 18-12-13, 08:30
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How did Westwood handle copy protection for Red Alert 2 and Tiberian Sun? The game does some funky stuff with the CD during gameplay instead of reading the disc like normal if it was simply playing a music file.

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Posted on 18-12-13, 09:18
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Posted by wertigon
There are a few brilliantly simple copyright schemes though. One of the best ones I found out about was on the StarCraft CD (I think?) where the outer layer of the disk was circular and played the exact same message a certain number of times before jumping to another part of the disk.
My favorite was the TurboCD "copy protection", which wasn't even intended as such(in the TurboGrafX's day, being on CD WAS copy-protection).

Instead of the standard "data on track one, redbook audio after that" that is the observed behavior on pretty much every multi-mode optical disk ever, NEC put a "don't play this in your stereo, it contains data files" redbook track on track 1, then data, then more redbook.
This was just off-standard enough that a lot of computer stuff refused to believe it it was a working CD at all.

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