xArpChat

ARP Chat is a console-based chat application written in 🦀Rust🦀 that uses the ARP (Address Resolution Protocol) for messaging over a local network.

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This project is a rewritten version of the original arpchat created by kognise.

The primary goal of this rewrite was to gain hands-on experience with network programming in 🦀Rust🦀.

While this version introduces some new features, it is not meant to be an improvement on the original.

Instead, it serves as an exploration of ARP, a protocol traditionally used to map IP addresses to MAC addresses, repurposed here for direct communication between devices.

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Key Features

The original ARP Chat implementation supports sending messages tens of thousands of characters long, thanks to a transport protocol built on top of ARP (which I named KTP — Kognise's Transport Protocol), with a bit of compression added.

There's even a presence discovery and heartbeat system, which not only provides join and leave notifications but also maintains an updated list of online users.

For more technical details, check out the article written by the original author.

In this rewritten version, I've added several new features:

• Written on stable Rust 1.81 (the original was written on an older nightly (beta) version).
• Refactored and stabilized the codebase (but I'm bad at programming, so don't judge me too harshly :)
• Updated dependencies and adjusted the code to accommodate breaking changes.
• Added logging functionality.
• Introduced localization (currently available in English and Ukrainian).
• Implemented the ability to export chat.
• Added a help window.
• Made various other minor improvements.

This project builds on the solid foundation of the original while bringing it up to date and adding a few enhancements.

Running

You can download program from the releases page.

Windows:

You'll likely need to install Npcap. During installation, make sure to check the option "Install Npcap in WinPcap API-compatible Mode."

Linux:

libpcap is already installed on most Linux distros. But to avoid running the program under sudo every time, you may have to grant privileges:

sudo setcap CAP_NET_RAW+ep /path/to/arpchat

After that, just run the binary in a terminal. If you see your own messages when you send them, everything is working correctly. If not, try selecting a different interface or protocol.

Encounter any issues? Feel free to open an issue (or make a pull-request), and I'll likely help you out.

Building the Project

Simply clone the project and start working!

git clone https://github.com/xairaven/arpchat-rs.git
cd arpchat-rs
cargo build

If you are using Windows, download the WinPcap Developer's Pack. You will need the Packet.lib file, which is located in WpdPack/Lib/x64/.

There are a couple of ways to link it:

• Set the LIB environment variable to the path of this file.
• The project includes a special build.rs file. It specifies the search for libraries to link in the lib directory, if such a directory exists at the root of the project (at the same level as src).
• A less recommended option: add the file to the toolchain libraries. An example path is:

C:\Users\<Your-User>\.rustup\toolchains\<Your-Toolchain>\lib\rustlib\<Same-Toolchain>\lib\Packet.lib