Is it possible to decompile c++ to Source Code

[ant_spy_binns]

Hello, I have a question and hopefully somebody has the answer, is it possible to the compile or just get some code fragments from a .dll compiled with c++, I know it's possible with Visual Basic's.
I've been working on a project for a while now, but can't get some of my code to work correctly, I've been making a steam.dll proxy that mimics all of the original functions from the steam.dll what allows me to hijack the function if I wish.
The reason for this project is so I can hijack the steam guard and the Email verification functions so I wouldn't need access to the victims Email to disable those features.
But I know it's possible I just can't get the thing to work, but I found a similar project, but it unlocks the games content in steam, i did contact the developer on how he got his code to work but didn't get a reply, whats fair enough I guess.
But now you see my problem, that's why I was wondering if it was possible to be compiled a .dll, compiled we've c++ so I can see how he did it.

Any information on this would be much appreciated I'm pretty much on my last stand with this project and might have to put it in the bin, if I can't get it to work, what would be a shame since I've spent so much time on it.

[mencore]

Re: Is it possible to decompile c++ to Source Code

That wall of text and I still dont understand what you mean.
You want to compile a .dll? You want part of Steam-dll's code into your own .dll?

[redbulli]

Re: Is it possible to decompile c++ to Source Code

If that would actually work steam guard would have to be very poorly coded. I doubt it will give you acces without having the code entered, because stuff like this is normally completely server sided.
So even if you manage to manipulate your client, you won?t be able to send a valid code.

[ant_spy_binns]

Re: Is it possible to decompile c++ to Source Code

That wall of text and I still dont understand what you mean.
You want to compile a .dll? You want part of Steam-dll's code into your own .dll?

Sorry maybe I should have been more clear, sorry.
I do not want to decompile the steam.dll, but I want to decompile somebody else's .dll what hijacks functions from the steam.dll, so I can see how they did it, if that makes more sense hopefully lol.

If that would actually work steam guard would have to be very poorly coded. I doubt it will give you acces without having the code entered, because stuff like this is normally completely server sided.
So even if you manage to manipulate your client, you won?t be able to send a valid code.

you are partially correct, it is mostly server side, but you can still manipulate the client into thinking you've already enter the valid code, here is a video showing that it can be done this is one of our old projects that no longer works anymore because steam started using interfaces to call the underlying function.
And that's why I wanted decompile somebody else's crack so I can see how they got around the interfaces.

[mencore]

Re: Is it possible to decompile c++ to Source Code

Sorry maybe I should have been more clear, sorry.
I do not want to decompile the steam.dll, but I want to decompile somebody else's .dll what hijacks functions from the steam.dll, so I can see how they did it, if that makes more sense hopefully lol.

Theres not really any way to 100% rebuild apps that are written in C++, people usually use reverse-engineering for tasks like this...
If it's not packed you can see what IDA + Hex-Rays makes out of it but it still requires you to understand ASM and C++ -syntax.
Also if it's linked with debug-symbols it helps but only retards release their programs that way.

[GetJump]

Re: Is it possible to decompile c++ to Source Code

As mencore said, you only can understand what's going on under the hood.
There is many techniques how to do it(hex/detour/api call monitor/ida/olly).
But you can't get origin code, no way.

[wav]

Re: Is it possible to decompile c++ to Source Code

Any hope of recovering usable code rests in a sufficiently advanced decompilation engine. The best one I know of is Hex-Rays. It's not usable against packed code, or virtualized code blocks as you have to attack the vm and it's handlers to reconstruct valid x86 to decompile.