Reverse engineering an obfuscated codebase and fixing it in the process

Today’s mandatory reading is How I cut GTA Online loading times by 70%.

As someone who’s been fighting the protection/obfuscation cat & mouse game for twenty+ years, let me tell you one thing. The way this guy reverse-engineered parts of the GTA5 codebase and then proceeded to single-handly triage and fix a long-standing (7+ years) performance issue is simply mindblowing. All he had to work with were heavily obfuscated dlls. This also shows how we, the protectors, are always playing a losing game.

There seems to be some sort of an obfuscation/encryption at play here that has replaced most instructions with gibberish. Not to worry, we simply need to dump the game’s memory while it’s executing the part we want to look at. The instructions have to be de-obfuscated before running one way or another.

Make sure you read this stuff.

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