Cantordust-Ghidra

CantorDust is a binary visulization tool used to aid reverse engineering efforts. It allows humans to utilize their superior visual pattern recognition to identify patterns in binary data.

CantorDust (then ..cantor.dust..) was originally created by Chris Domas (xoreaxeaxeax), with funding from Battelle. The Ghidra plugin version of CantorDust was primarily developed by Battelle interns AJ Snedden and Mike Sengelmann with funding from Battelle.

Take a look at this blogpost to learn more about the algorithms and history behind this tool.

Cantordust is dependent on Ghidra version 9.1 or higher

Installation and Setup:

1. Clone the repository from Github

2. Install Ghidra 9.1 or higher (Cantordust requires this version or higher)

   1. Download from: https://ghidra-sre.org
   2. Refer to the Ghidra Installation Guide: https://ghidra-sre.org/InstallationGuide.html

3. Open Ghidra and start a new Project

4. Map the Script Manager to your cantordust repo

   1. Click the green play button in the task bar (script manager)
   2. Click on the icon called "script directories" when hovered over
   3. Click the green + (plus sign) and add the cantordust directory to the list

5. Run Cantordust for testing

   1. Filter the script manager for Cantordust.java.
   2. Highlight the file and click the green play button

You can also assign a key binding to Cantordust.java by right clicking on the plugin.

Updating Cantordust:

1. Navigate to your cantordust/ directory that stores this repository.
2. run: git pull
3. run: python cleanup.py
   • If this doesn't work, refer to "Development Tips:", section "Ghidra Script Compilation" for details on setup of your cleanup script.
4. Open up Ghidra and launch Cantordust as normal.
   • If you're having trouble, refer to "Installation and Setup: Steps 4-5"

Development Tips:

Feel free to make modifications, changes and updates to this repository. Below are some tips on how to get started.

Ghidra Script API

The Ghidra API is your friend. When in ghidra go to: "Help", and select "Ghidra API Help". This will take you to an interactive html page which provides everything you need to know in order to interact with the API.

In order for Ghidra Scripts to work, the file that is run must extend GhidraScript like so:

import ghidra.app.script.GhidraScript;
public class Cantordust extends GhidraScript { }

This class Cantordust is the only class that can interact with the API.

When adding a new .java file to the repo, make sure you pass cantordust to it as a parameter in it's initialization. The only way you can print when testing a ghidra script, is by calling the class that extends GhidraScript and then calling your print statement. This will print in the Ghidra console. Example Below:

cantordust.printf("");

Ghidra Script Compilation

Ghidra Scripts are not automatically recompiled at runtime. This means that in order for you to make sure your live changes actually get applied at runtime, you need to delete the related .class files that Ghidra generates at compilation. Ghidra stores these class files in a directory labeled bin that is unique to every user, making it difficult to automate. We currently do this with a python script, cleanup.py, which looks for a file within the same directory called ghidra_bin_location.txt. Our python script expects the txt file to contain a utf-8 encoding of your specific bin location where the .class files are generated. The python script then will delete every .class file within the directory. ghidra_bin_location.txt must exist and contain the ghidra bin folder location for it to work properly.

Update: We have made advancements in automating this process, where Cantordust.java will actually locate the bin directory for you and write the location in a ghidra_bin_location.txt file for you at runtime. If this doesn't work on your operating system for whatever reason, the cleanup script will not work and you will have to create the ghidra_bin_location.txt file yourself.

Here is an example file location on a linux system:

/home/user/.ghidra/.ghidra_9.1_PUBLIC/dev/ghidra_scripts/bin/

If you run into issues when running the script, this is probably because of the UTF encoding in your txt file. It should be UTF-8, but if you're having trouble figuring out how to force this you can edit the python script to decode UTF-16 instead.