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Comment by a2128

5 days ago

My mistake, I just assumed their Byfron anti-cheat is kernel level because that's the most common reason why anticheats take issue with Wine. If their anti-cheat operates entirely in usermode, then their decision to block Wine is even more baffling to me.

It is not kernel level, they use a number of pretty fancy user mode tricks to prevent people messing with the game.

They encrypt every page and register an exception handler that decrypts the page when a fault is reached to keep memory secure. They do cache timing checks to see if a page was recently in the working set outside of the expected control flow and will flag you if you fail the check too many times because it indicates tampering.

  • While the page decryption trick should work in Wine just fine (ZeroIT Lab Theia does that too, right?), I don’t remember if Wine provides workingset info like Windows.

    • Yes, it does. Wine lets you register a VEH. They do other stuff to prevent Wine and virtual machines in general that I am not fully aware of.

      Even then it's just a fancy party trick, you can suspend the process call the decryption function enumerating all the pages and take a full dump to get the binary

      FYI; Theia is a very bad product. It absolutely tanks binary performance and does little to prevent a moderately competent engineer from cheating in your game.

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