[PS4] The Idolm@ster Platinum stars

Extraction and unpacking of game archives and compression, encryption, obfuscation, decoding of unknown files
minmode
Posts: 3
Joined: Mon Mar 02, 2015 8:12 pm

[PS4] The Idolm@ster Platinum stars

Post by minmode »

Hopefully someone could take a look at the encryption in this game, every file besides audio is encrypted and have the header MZNC.
I've included some sample files and the eboot, thanks for any help.

https://mega.nz/#!VPRUnTZB!Ib-YZz3gDXlhWx05qW4biPlR6b-Jxqqzc7p8gxIId_s
aluigi
Site Admin
Posts: 12984
Joined: Wed Jul 30, 2014 9:32 pm

Re: [PS4] The Idolm@ster Platinum stars

Post by aluigi »

I bet there is some implementation of the Mersenne Twister involved due to the following constants:
5489 6364136223846793005 62
But that's only part of the puzzle
id-daemon
Posts: 1040
Joined: Sun Mar 22, 2015 7:09 pm

Re: [PS4] The Idolm@ster Platinum stars

Post by id-daemon »

aluigi wrote:But that's only part of the puzzle

Yes, it was only the tip of the iceberg. The guys did all the tricks to do it properly. Custom Mersenne Twister to make different unique key & IVec for each file. Separate seed for each sequence is also encrypted and so on...

But there's always a way to crack it:

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Examples of polycount:

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