Cheat Engine

grease · How do I cheat? Reputation: 0 Joined: 25 Mar 2023 Posts: 6

Hello friends! I'm new to using Cheat Engine and having a blast, but I can't quite figure out the assembly syntax for tutorial step 9. I keep getting this error when I try to compile a script to solve the challenge. The issue is from trying to mess with the floating point registers. Can someone maybe take a look at my script and let me know if you see me doing anything wrong?[/img]

ParkourPenguin · Posted: Sat Mar 25, 2023 7:55 pm Post subject:

memory-to-memory moves generally can't happen. Use a register as an intermediary.
If you're just moving data, `mov` w/ general purpose registers works fine. If you're doing any floating point arithmetic, use SSE instructions and registers (e.g. `movss`, `xmm0`).

`teamEnemyValue` is label that's undefined. Place it after a well-defined address.

`jmp returnhere` / `popfq` are placed after `"Tutorial-x86_64.exe"+2F25D`, not `newmem`. This will overwrite code after the injection point that you didn't intend to overwrite.

`popfq` isn't doing any good after the jump to the return label.

grease · How do I cheat? Reputation: 0 Joined: 25 Mar 2023 Posts: 6

Thanks for responding! I've seen your replies in other threads, thanks for being a resource. I am new to code injections and I'm having a lot of issues figuring out whats happening when I click execute.

`teamEnemyValue` is label that's undefined. Place it after a well-defined address.

What do you mean by this? I can see in the error message that it's getting shoved all the way to the top address ([fffffffffffffff]), but why? I was under the impression the function label(fooBar) would handle this mapping process. Does the order I place the labels in the script affect what memory address they're mapped to?

`jmp returnhere` / `popfq` are placed after `"Tutorial-x86_64.exe"+2F25D`, not `newmem`. This will overwrite code after the injection point that you didn't intend to overwrite.

This sounds like something really important I have yet to figure out. So from my understanding, we enter the script at the address label ""Tutorial-x86_64.exe"+2F25D`. After allocating some memory, we jump into this "memory cave" we created using the newmem label and start executing our fucker code. after that gets executed, we jump back to where the code should have executed to begin with (originalcode). My question is, how does the code get unintentionally overwritten? I see alot of people posting algorithms to do like one-hit-kills or something to solve the challenge, but haven't yet seen any explanation about the wrapper code that handles the injection itself. Does that make sense?

ParkourPenguin · Posted: Sun Mar 26, 2023 12:45 pm Post subject:

`label(fooBar)` simply tells CE there should be a symbol named "fooBar" that gets defined somewhere in the script. It declares the label exists: it doesn't define an address for it.

In order to define an address for a label, you have to place it in the script somewhere with a semicolon after it. i.e. `fooBar:`
The address it gets assigned is based on where it appears in the script.

grease · How do I cheat? Reputation: 0 Joined: 25 Mar 2023 Posts: 6

I'm understanding! Cool, so when programming in assembly, you have to pay attention to the amount of space your instructions themselves are filling. Especially at the injection point, where you have to make sure that the injection script itself doesn't alter the amount of memory the original instruction filled. In this case we can tell that the orignial instruction filled 6 bytes, because 2B4C2 - 2B4BC = 6

It helped alot!

EDIT: So I've had a couple hours to fuck around and try to fix it based off what you told me, and I'm still running into issues defining the address for TeamEnemyValue. I tried to place the label in a location that would be well definied in reference to newmem and got the same error I was getting before. I tried to experiment based on what I now know about how this script compiles by trying to define a location for the data in reference to newmem using arithmetic. This also did not work, for the same reason. It seems to me it does not like it when I try to leave a address to be defined at compile time, so trying to use newmem as a base raises errors. But I see other people format their code like this as well. Do you think I'm still making programming errors, or do you think there may be some issues with my settings?

ParkourPenguin · Posted: Mon Mar 27, 2023 11:57 am Post subject:

Instructions like `mov [rdx],[whatever]` tries to access 2 memory locations in the same instruction. As I've said before, this generally can't happen. You need to use a register as an intermediary. I'd suggest xmm0 since the game is already using it.

grease · How do I cheat? Reputation: 0 Joined: 25 Mar 2023 Posts: 6

Thank you based penguin. I was mistakenly equating registers and memory addresses. I am now a graduate of Cheat Engine Tutorial x86_64 academy Very Happy

m0rc0m · Posted: Wed May 31, 2023 12:46 pm Post subject:

You can't do memory to memory instructions