Cheat Engine

caval · How do I cheat? Reputation: 0 Joined: 14 Sep 2023 Posts: 8

Hey

There is process A, my target. I am coding process B.
B wants to intercept a known instruction of process A, for which I know the address.
I want to read a specific register used by the instruction.

So I want to accomplish a task that CE is able to do already, yes.

What is the best way to accomplish that ?
I guess I should use c lang, but I don't know the libs, the implications, to estimate globally the difficulty of that task that seems trivial.
Lets say I want to use Hardware breakpoint since I just need a single one, alongside VEH debugging ? Just to have a general direction.

ParkourPenguin · Posted: Mon Sep 18, 2023 6:56 pm Post subject:

So basically, how to make a debugger from scratch? That involves far more than what can be explained in a single forum post.

Microsoft's documentation:
https://learn.microsoft.com/en-us/windows/win32/debug/basic-debugging

CE's source:
https://github.com/cheat-engine/cheat-engine

caval · How do I cheat? Reputation: 0 Joined: 14 Sep 2023 Posts: 8

Mmh maybe I don't have to go so far.

I wonder if there is a way to have a script which could interact with my custom program B.
program B would call that script, which would attach a debugger to program A then look for value in the breakpoint it set at <target address instruction>, and then detach. Thus, returning back the values found to program B.

I see that as a pretty low level language script, called by probably my higher level language program B.
I guess this script would have to be executed by CE, and since I don't need CE UI I'd require some sort of headless CE

ParkourPenguin · Posted: Tue Sep 19, 2023 10:39 am Post subject:

The closest thing to a headless CE is making a trainer with most of CE packed into it. The trainer doesn't have to have a UI.
Execute the trainer from program B and communicate with it via some form of IPC (e.g. allocateSharedMemoryLocal; see sharedMemory.pas)

A code injection would be far simpler- no need to use CE. There's plenty of tutorials on this for a variety of programming languages.

caval · How do I cheat? Reputation: 0 Joined: 14 Sep 2023 Posts: 8

Ok I will look into code injection. I probably need to inject the code near the target instruction address, in order to leak the register value to some shared memory or other IPC.

Thanks for the tips