Toy packet injection engine for learning rust & reverse engineering with one of my favorite games ever.

As of now, this project just functions as a simple Diablo2 game server packet sniffer.

Note: Most game related code has been organized into a standalone library libd2r to support this and other tools

Goals

• cross platform without runtime/VM requirement
• low overhead to potentially run many instances
• do not modify game memory, instead read and write raw network packages
• reproduce game state as accurately as possible/needed
• enable clientless game connections

Milestones

1. Read, Decode, and Print network packages for Game-, Realm-, and BNetChat servers (this is now entirely done in libd2, see repo)
   • [x]
2. Priority based event handling for passive modules (e.g. chicken, pickit, [move, combat, ...])
   • Chicken module
   • Pickit module (parse configuration from .nip files, see kolbot)
3. Pathing and Collision
   • Implement pathing (to walk/teleport to location on the same map)
   • Navigate to arbitrary locations in the game, considering found waypoints, quest state
4. allow scripting with gluon, dyon, lua, wren, TypeScript?
   • TBD

How to Build

Linux

Tested with Diablo 2 (Legacy) and WINE cargo build --release

Mac Os

cargo build --release (not tested yet)

Windows

You will need to install ncap or the WinPcap Developers Pack as per the libpnet build instructions for Windows (I tested the latter). Then point your user environment variable LIB (create if nonexistent) to the folder where to find Packet.lib i.e. WpdPack/Lib/x64/ from the WinPcap Developers Pack you just downloaded. Then cargo build --release This will get the project building.
Currently, in order to find the internet-connected network interface, it is necessary to disable disconnected-but-enabled interfaces (such as virtual adaperts for VPN).

How to Run

1. Launch a Diablo II client.
2. Execute target/release/d2ng which will launch a command window
3. Connect to b.net and watch the output of the packet sniffer in the command window (packet id + payload as hex)

Disclaimer

Little of this works yet and most probably never will. Unless you feel like contributing, which is welcome, it is mostly an exercise. Heavily inspired by an old client-less C# bot by dkuwahara and a blog post by Eric Carmichael and, of course, D2BS. Another good resource is the diablo 2 protocol js library.