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View Full Version : Funny details on the "protection" of software HD players


dELTA
January 21st, 2007, 07:41
As most people probably know, both HD-DVD and Blu-ray movies have now been successfully decrypted (and at least in the HD-DVD case, released on the warez scene), by stealing decryption keys from the memory of software players.

As we did of course already know, it is not theoretically possible to prevent this on normal PC hardware, but with all the fuzz about software player companies having to "promise" really good to protect the keys well in memory, it's always fun to hear about their super powerful protection, codenamed "let's-leave-the-keys-completely-unencrypted-in-memory", and the simple method that could be used by Muslix64 to find them (no code reversing at all, quite nice job actually, simple but elegant method, and a proof of what can be done by just using your brain and thinking outside the box).

More details in this thread, by Muslix64 himself among other people:

http://forum.doom9.org/showthread.php?t=120869

(Please don't post any links to this board in that thread or in other threads on that board at the moment though, even though there is some (very low-level) reversing-type discussions going on there right now. The media industry will most likely shoot with the big guns at anything that moves at the moment, completely unrelated/irrelevant or not.)

LLXX
January 21st, 2007, 08:24
I knew it'd be broken, this is probably not the first successful attempt but only the first publicly announced attempt.

He's certainly thinking outside the box; if I were in his position I'd have at the software with a debugger, since decryption algorithms are rather easy to recognise in memory and where there's an algorithm, there's input data (including the key).