Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by awestroke on Saturday December 24, 2022 @09:49AM
(#34117245)
No, encryption is very different from obfuscation, even if the former is often used in the latter
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Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by xurukefi on Saturday December 24, 2022 @09:54AM
(#34117318)
You missed the point. maria2 is talking about whitebox crypto. The "whitebox" part means that the decryption process happens on your machine incuding the secrets, which are present in some obfuscated scrambled form in memory. Getting the secret key is a matter of debugging and understanding the obfuscation scheme. A prime example of this is DRM like Widevine (L3) in the chrome browser.
Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by bitexploder on Saturday December 24, 2022 @10:18AM
(#34117572)
I am really failing to understand the distinction here. Encryption with say, AES has very different properties and use cases compared to an obfuscation scheme. You can use encryption as a part of an obfuscation scheme, but obfuscation is a shell game, all the way down. Crypto is not, mathematically. They are categorically different things, right?
Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by grog454 on Saturday December 24, 2022 @10:53AM
(#34117933)
The math is irrelevant when the key is known to all parties.
Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by bitexploder on Saturday December 24, 2022 @11:11AM
(#34118129)
Sure. That is DRM and obfuscation in a nutshell. How annoying can I make this for you to reverse engineer?
Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by toast0 on Saturday December 24, 2022 @11:17AM
(#34118213)
Obfuscation with encryption can be done with good ciphers, like AES, but the key is still shipped with the code, so it's still just cat and mouse.
It's a little different if the key is hardware specific, so each binary only runs on one system and it's hard to extract the keys, but that's not a typical setup. Usually it's this code needs to run on the general public's computers or phones, and that's too general a target to rely on hardware crypto.
Re:Reverse Engineering TikTok's VM Obfuscation (Part 1)
by matmann2001 on Saturday December 24, 2022 @01:55PM
(#34119895)
The key specifier word was "whitebox". They aren't speaking generally about cryptography.