Identifying Encryption Patterns

[moeyyas]

This is for the people who worked with decryption of files (mostly game related files).
I have a basic idea of how the process of decrypting an entire file goes, the only thing missing is how to identify the encryption pattern(s).
I understand it's mostly done by observing how user input changes the data? But even if so, even if I know that the value "somevalue" equates to "503241567" after encryption, there can be so many ways to achieve that result without it being the encryption that that specific program uses.

My question is: How can I identify a file's encryption?

Looking forward to your guys' response!

[Orinion77]

google for PEiD if you want to check a exe. For game files like libraries its easiest to dump the from the running application (for example in StarWarsBatllefront).

[moeyyas]

google for PEiD if you want to check a exe. For game files like libraries its easiest to dump the from the running application (for example in StarWarsBatllefront).

Thank you for your response!
I understand what you mean, and I understand what PEiD does and what dumping is, but how does dumping the library help me decrypt the game files?
When you say libraries you mean the ".dll" that the game uses, right? how does that help?

[♪~ ᕕ(ᐛ)ᕗ]

Best way is of course to reverse it in Olly and find out how the game actually decrypts the files.
P.S. not that easy, especially if you're dealing with some fancy encryption and you're a newbie.

[moeyyas]

Best way is of course to reverse it in Olly and find out how the game actually decrypts the files.
P.S. not that easy, especially if you're dealing with some fancy encryption and you're a newbie.

I see that's why he suggested to use PEiD and dump the process, to be able to debug it.
I will make a simple encryption and start practicing on my own, maybe that will help me get used to it!

[♪~ ᕕ(ᐛ)ᕗ]

I see that's why he suggested to use PEiD and dump the process, to be able to debug it.
I will make a simple encryption and start practicing on my own, maybe that will help me get used to it!

Use crackmes and keygenmes to get your hands on it