DOOM 3 BFG Edition Profile

DOOM 3 BFG Edition includes a profile.bin file in the users save data. This file includes (presumably) default console variable (CVar) settings, along with some additional data which appears to be default input mappings.

The file contains two checksums calculated from the contents of the data, so you cannot simply edit the file without knowing how to re-calculate the checksums otherwise the game will detect the file as corrupt on start-up and create a new profile.bin.

This Python package allows you to open a profile.bin file, make changes to it, and then write it back to disk with the correct checksums.

But why?

I wanted to experiment with changing settings on console versions of the game, where access to the in-game console is not readily available. In the PlayStation 4 version of the game the profile.bin file is located within the users encrypted PS4 save data. With a jailbroken PS4 you can decrypt the save, edit the profile.bin file with this Python package and then re-encrypt the save data. The modified settings are now loaded by the game.

Installation

pip install doom3-bfg-profile

Typical Usage

• Create a BFG_Profile object by loading and parsing an existing profile.bin
• Add/change/remove console variable settings
• Save the new profile.bin by calling generate_profile()

Limitations

I was only interested in editing the console variables section of the profile.bin file. I have not investigated the section which appears to be default input mappings, so any profile.bin which contains such a section will have it re-created in the updated file as it originally was (identified as 'Extra Data' in the profile.bin data structure).

Usage Examples

Create a BFG_Profile object and add the com_showFPS = 1 console variable

import doom3_bfg_profile as d3

profile = d3.BFG_Profile('profile.bin')
profile.add_config_item(d3.Config_Item('com_showFPS', '1'))
profile.generate_profile()

A demo application is included in src/demo.py.

Reference

Profile.bin Structure

Data	Size	Description
Checksum 1	4 bytes	MD5 based checksum of all subsequent data (written big endian)
Checksum 2	4 bytes	MD5 based checksum of all subsequent data (written big endian)
Header	5 bytes	80 94 CC A1 04
Config Data Count	1 byte	Total number of key pair values in Config Data
Config Data	Variable	NULL terminated key pair values com_showFPS\x00 1\x00
Config Footer	19 bytes	17x 00 + C8 01
Padding	206 bytes	205x 00 + 01
Extra Data	Variable	Possibly default key bindings

Development

All commands after step 1 should be run from the root of the git repo

1. Clone the repo

git clone git@github.com:andshrew/DOOM3-BFG-Profile.git

2. Create and load a virtual python environment

python -m venv .venv
source .venv/bin/activate

3. Upgrade pip

pip install --upgrade pip

4. Install the package in editable mode

pip install -e ".[test]"

5. Build the final package

pip install build
python -m build