OpenChat

README

OpenChat (ChatSSH)

OpenChat (originally ChatSSH) is a secure, terminal-based, decentralized chat application. It combines cryptographic SSH channels, Bubble Tea text user interface (TUI) aesthetics, and go-libp2p peer-to-peer transport with NAT hole punching.

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Precompiled Downloads

Get the precompiled executable directly for your operating system:

• 💻 Windows: Download OpenChat-Win.exe (64-bit)
• 🍎 macOS: Download OpenChat-Mac.zip (Apple Silicon & Intel)
• 🐧 Linux: Download OpenChat-linux (64-bit)

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Useful Reference Guides

Learn more about using and configuring OpenChat:

• 🚀 Quick Start Guide — Step-by-step instructions on starting your first server and connecting clients.
• ⚙️ CLI Flags Reference — Complete configuration index for running custom settings via command-line arguments.
• 📐 System Design Document — Architectural layout, wire frames, connection models, and cryptographic details.
• 🔧 Security & Debugging Audit — Historical overview of issues resolved during security hardening (UTF-8, goroutine leaks, handshake retry logic).

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Core Features

• Interactive TUI Setup Wizard: Starts automatically if you launch the application without CLI arguments (e.g. when double-clicking the binary). Walk through step-by-step options (Username, Hosting vs. Connecting, Storage type) completely in the terminal.
• Premium Bubble Tea UI: Fully responsive terminal layout using Bubble Tea, rendering message feeds, colored timestamps, dynamic hashed username coloring, and a powerline-style status bar.
• SSH Encrypted Transport: Uses standard SSH protocols to execute encrypted end-to-end handshakes. Incorporates visual fingerprint checks (Randomart and Emojiart) for MitM verification.
• Decentralized NAT Traversal: Leverages P2P networking powered by libp2p. Autodetects networks, performs NAT hole-punching (DCUtR), and falls back to Circuit Relays to connect nodes behind firewalls automatically.
• Flexible Storage Profiles:
  • Local Encrypted Storage (Default): Saves chat history inside a local SQLite database encrypted with AES-256 (passphrase-derived key).
  • Ghost Mode: Volatile RAM-only message caching. Wipes and scrubs all chats from memory upon application termination, writing zero bytes to the disk.

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Build from Source

Prerequisites

• Go 1.22+ installed.
• GCC (Optional, for running tests).

Compile Binary

go build -o OpenChat ./cmd/chatssh

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Quick Start

1. Launch Setup Wizard

Double-click the downloaded binary file or run the compiled executable without parameters to load the interactive setup wizard:

./OpenChat

2. Connect from Terminal (CLI Option)

If you prefer to bypass the setup wizard and launch directly using the command line:

• Host a room:

  go run ./cmd/chatssh --mode server --addr :2222 --user alice
  

• Connect as a client:

  go run ./cmd/chatssh --connect "172.29.160.1:2222" --user bob
  

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Project Directory Layout

cmd/chatssh/          Application main entrypoint
internal/
  app/                Application setup, CLI parsing, and interactive setup wizard
  chat/               Event hub and subscriber mechanisms
  crypto/             Key exchange and fingerprint utilities
  keys/               Ed25519 secure key management
  p2p/                libp2p network stacks and NAT routing
  room/               Multiplexed room broadcasters
  sshclient/          SSH client wrapper
  sshserver/          SSH server implementation
  storage/            AES-GCM SQLite database and Ghost storage handlers
  tui/                Bubble Tea view and components
DesignSystem/         Original architecture design definitions
WebView/              Stunning 3D P2P landing page website assets

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Contributing

We welcome contributions to OpenChat! To contribute:

1. Fork the repository.
2. Create a feature branch (git checkout -b feature/NewFeature).
3. Commit your changes (git commit -m "Add some NewFeature").
4. Push to the branch (git push origin feature/NewFeature).
5. Open a Pull Request.