GDB Cheat Engine

Finds and uses cheats via the PythonGDB API

This is a utility class that uses PythonGDB's memory I/O functionality to aid in finding variables that can be used for cheats.

The I/O facilities are exposed through the PythonGDB's Inferior class. https://sourceware.org/gdb/onlinedocs/gdb/Inferiors-In-Python.html

Setup

$ gdb
  (gdb) source gdb_ce.py
  (gdb) python-interactive
  >>> ce = GdbCheatEngine(...)

Example

The following procedure demonstrates how to find the counter that holds a character's HP (health points). One might leverage this variable to implement a god-mode cheat.

$ gdb
  (gdb) source gdb_ce.py
  (gdb) python-interactive
>>> inferior = gdb.inferiors()[0]
>>> ram_addr, ram_size = (0x02000000, 1024 * 256)
>>> ce = GdbCheatEngine(inferior, ram_addr, ram_size)

>>> initial_hp = "\x00\x64" # 100 HP. Assumes that the counter is an unsigned 16bits variable
>>> ce.search_ram(initial_hp)
set([0x02000004, 0x0200..., ....])

# Reduce the HP...

>>> new_hp = "\x00\x60"
>>> ce.search_ram_again(new_hp)
set([0x02000004])

>>> hp_counter_addr = 0x02000004

More Docs

For further documentaiton, check out this blogpost - http://www.garin.io/game-cheating-tutorial