Hi guys. To begin with, thank everyone who reads this thread and sorry for my poor English. I usually play an online game called Audition. I love it and now want to modify it. Just to make it more interesting and see what I can do ( not like make tools or hacks ). In the game folder, I found a lot of files which have to be decoded, or unpacked/packed in order to modify it. Like .acv, .bin... Just wondering if anyone can look at them I tell me what I can do, what books I can read or so. I am a newbie in C/C++ so the more details, the better. I really really appreciate.. Here is the link to download some files.. http://www.mediafire.com/?jium42i4m5z Have a great day :)

Quote:Original post by lc_lumos
I usually play an online game called Audition. I love it and now want to modify it.

Stop right there. What you're trying to do is already illegal. You might get away with it if you never show your results to another living human being, but I doubt you'll get any help for analyzing those files around here. Since it's an online game, it would also be surprising if your modified version will work. Ideally, the game will detect the changes and refuse to connect, citing corrupt game files.

I would also suggest that you remove that link, since that is technically reproduction without consent of the rights holders (in other words, warez).

It is perfectly legal to do anything you want with data you have on your computer, thankfully.

It is also legal in most countries, including the US, to distribute reverse engineering information for interoperability purposes.

Quote:Ideally, the game will detect the changes and refuse to connect, citing corrupt game files.

There is no way the server can prevent the client from doing anything it wishes. That kind of system is easily circumventable, if in place.

You should also keep in mind that modifying that game's data is also forbidden under these terms; you'll also want to read their EULA to be sure (EULA usually being draconian in their restrictions but it's still a binding contract between you and them). Their "admin fee" is five or ten times the character level in Singapore dollars (looks like they are trying to profit from all those crackers - interesting idea). The permanent ban will hurt, too, although it is certainly more digestible than a lawsuit.

Audition seems to use GameGuard to detect client-side tampering, although I have no clue about how effective it is. It is true that these systems can be circumvented (there is no such thing as foolproof on clientside), but we're certainly not gonna try to help you do it :)

Um sorry that I forgot to say that there is an offline version of that game. I am not like a hacker who wants to cheat or hack in game. I am just a normal player who tries to learn what I can do like make a mod. I will not share it to anyone. Actually, I usually play it alone, like make a dance room and lock it. The idea is I want to change some color, some pictures, some textures to make it different and more interesting. Therefore, can I do it with the offline version, just to learn or discover the game? That's it :)

Quote:Therefore, can I do it with the offline version, just to learn or discover the game?

Yes you can.

Quote:Just wondering if anyone can look at them I tell me what I can do, what books I can read or so

Since this is about modifying a proprietary piece of software, the only place where you may find some information is various forums and communities that deal with modding, hacking or exploiting the game. There might not be any such communities for this particular game.

Quote:I am a newbie in C/C++ so the more details, the better

There is no use for C++ in modding.

Quote:I found a lot of files which have to be decoded, or unpacked/packed in order to modify it.

Can you unpack them already, or have a tool that does that? If no, then you'll need to find one, or write one yourself. Reverse engineering however is not a topic that is covered by tutorials since it may require in-depth knowledge.

For specific formats, you could try Xentax, they used to take a look at just about everything and provided editors.

If you want to learn the basics of reverse engineering in a video game context, I would recommend the following books:
Reversing: Secrets of Reverse Engineering (a must!)
Exploiting Software: How to Break Code
Exploiting Online Games: Cheating Massively Distributed Systems

You will also need to study Assembly Language and get familiar with the Windows PE format and how security is implemented to protect them. The Art of Assembly Language Programming (just the version I find easiest to refer to, Google Books has a version too) is the book you will be referring to as you start learning how Assembly works.

All are great resources that you can read to get the basics down of Reverse Engineering when it comes to games. You could just Google search for tutorials, but the problem with that is the information is mostly written by people who don't know what they are doing and as a result you will have a weak foundation and go about things the wrong way. That is not to say that you should ignore everything on the web, it's just unless you are motivated enough to learn this stuff on your own without any guidance, then you should be aware of the materials out there that mostly do more bad than good for a learning experience.

Either way though, the profession of reverse engineering is one that is experience driven. You learn by doing it yourself and failing a lot and then trying it again until you succeed. It's hard, time consuming, and can be very frustrating if you don't have a passion for it. Once you learn the basics and start getting better at it, you will gain new insights on how software works and build up a nice skill set that you can apply to a large number of tasks that can make you a more efficient programmer, debugger, and reverse engineering enthusiast.

While a lot of people associate malicious game hacking with reverse engineering applied to games, that's not the case here. I would encourage every serious program to understand the basics of reverse engineering, how to read and mentally follow assembly, as well as build up experience with advanced debuggers and decompiler such as OllyDbg as those skills and tools are invaluable to programmers trying to solve problems with their code or the code of others whom they are working with.

That especially goes for anyone who is writing code that will be operating over a network! Unless you understand how easy it is for your code to be broken, you will never be able to design a solution that will withstand attacks. Security engineering is vital in this day and age and too few people write it off or just don't have any understanding of it. There is nothing magical about it either. You don't have to be super smart, great at math, a PhD student in CS, all you need is a little hard work, determination, and time and you can learn a lot in a relatively short period of time.

Quote:
Can you unpack them already, or have a tool that does that? If no, then you'll need to find one, or write one yourself. Reverse engineering however is not a topic that is covered by tutorials since it may require in-depth knowledge.

Thank for helping me.Actually, there are some people who had written a soft to pack and unpack those files. However, because a lot of people used it for hacking and cheating, those files are now used by only few people who make those softs. I am trying to contact with them because my purpose is different from hacking or cheating.

Quote:Drew_Benton

Thank you so much. I really really appreciate your help.