SCAR Chat

Written by Claude Sonnet, with assistancer from Ganome.

A cross-platform C++20 chat application with text messaging, live video streaming, and screen sharing capabilities.

Features

• 🔐 Secure Authentication - User/password with Argon2 hashing and JWT session management
• 💬 Real-time Text Chat - Instant messaging with online user list
• 🎥 Live Video Streaming - Camera feed sharing via Pipewire (Linux)
• 🖥️ Screen Sharing - Multi-platform screen capture (X11/Wayland/Hyprland/Windows)
• 🎨 Modern UI - Dark Discord-inspired Qt6 interface with grid video layout
• 🔒 SSL/TLS - End-to-end encrypted connections via Boost.ASIO
• 📱 Cross-Platform - Desktop (Linux/Windows) and Android support

Architecture

• Language: C++20
• GUI Framework: Qt6
• Networking: Boost.ASIO with SSL
• Database: SQLite3
• Hashing: Argon2
• Auth: JWT tokens
• Media: FFmpeg, Pipewire, DBus portals
• Build: CMake 3.20+

Project Structure

scar-chat7/
├── client/           # Qt6 GUI client (scarchat)
├── server/           # Boost.ASIO server (scarchat-server)
├── shared/           # Common protocol and utilities
├── dbmanager/        # Database management CLI tool
├── third_party/      # External dependencies (Argon2, JWT-CPP)
├── tests/            # Unit and integration tests
├── installer/        # WiX installer scripts
└── CMakeLists.txt    # Root build configuration

Prerequisites

Linux

# Ubuntu/Debian
sudo apt install build-essential cmake qt6-base-dev libboost-all-dev \
    libssl-dev libsqlite3-dev libpipewire-0.3-dev \
    libavcodec-dev libavformat-dev libavutil-dev

# Fedora
sudo dnf install gcc-c++ cmake qt6-qtbase-devel boost-devel \
    openssl-devel sqlite-devel pipewire-devel \
    ffmpeg-devel

Windows

• Visual Studio 2022 (with C++20 support)
• CMake 3.20+
• Qt6 (install via official installer)
• Boost (via vcpkg or pre-built binaries)
• OpenSSL (via vcpkg)
• SQLite3 (via vcpkg)
• FFmpeg development libraries

Android

• Android NDK r25+
• Qt for Android
• Android SDK with minimum API level 24

Building

Linux/Windows Desktop

# Configure
cmake -B build -DCMAKE_BUILD_TYPE=Release

# Build
cmake --build build --config Release

# Optional: Build only server or client
cmake -B build -DBUILD_CLIENT=OFF  # Server only
cmake -B build -DBUILD_SERVER=OFF  # Client only

Binaries will be in:

• build/server/scarchat-server - Server executable
• build/client/scarchat - Client executable
• build/dbmanager/dbmanager - Database management tool

Android

# Requires Qt for Android and Android NDK
cmake -B build-android \
    -DCMAKE_TOOLCHAIN_FILE=$ANDROID_NDK/build/cmake/android.toolchain.cmake \
    -DANDROID_ABI=arm64-v8a \
    -DANDROID_PLATFORM=android-24 \
    -DQt6_DIR=/path/to/Qt/6.x.x/android_arm64_v8a/lib/cmake/Qt6

cmake --build build-android

Usage

Server

# Start with default settings (looks for scarchat.db, server.pem, server.key in current directory)
./scarchat-server

# Specify custom paths
./scarchat-server --db /path/to/custom.db \
                  --cert /path/to/cert.pem \
                  --key /path/to/key.pem

Server Configuration:

• Database: scarchat.db (auto-created on first run)
• SSL Certificate: server.pem or via --cert
• SSL Key: server.key or via --key
• Config: server.json with hardcoded defaults as fallback

Client

./scarchat

Client Configuration:

• Settings stored in $XDG_CONFIG_HOME/scarchat/client.json (Linux) or %APPDATA%/scarchat/client.json (Windows)
• Remembers last username, server IP/hostname, port, and JWT token

Database Management

Use the dbmanager tool for user administration:

# Create a user
./dbmanager adduser alice password123

# Create admin with avatar
./dbmanager adduser admin adminpass /path/to/avatar.jpg
./dbmanager modifyrole admin admin

# List all users
./dbmanager list

# Search users
./dbmanager search role admin

# Fetch user details
./dbmanager fetch alice

# Modify user
./dbmanager modifypass alice newpassword
./dbmanager modifyemail alice alice@example.com

See dbmanager/README.md for complete documentation.

Database Schema

The scarchat.db SQLite database contains:

CREATE TABLE users (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    username TEXT UNIQUE NOT NULL,
    password TEXT NOT NULL,      -- Argon2 hash
    salt TEXT NOT NULL,
    token TEXT,                   -- JWT session token
    status TEXT DEFAULT 'offline',
    role TEXT,                    -- Optional
    email TEXT,                   -- Optional
    last_login INTEGER,           -- Unix timestamp
    avatar_pic BLOB               -- Optional
);

Security Model

1. Client → Server Login:

   • Client sends username + plaintext password over SSL
   • Server fetches user's SALT from database
   • Server computes Argon2 hash and verifies
   • Server generates JWT token on success

2. Session Management:

   • JWT stored in database TOKEN field and client config
   • All subsequent requests authenticated via JWT

3. Transport Security:

   • All connections enforce SSL/TLS
   • No plaintext transmission outside SSL layer

Windows Installer

Build the MSI installer using WiX Toolset:

# After building the Release binaries
cd installer
candle -ext WixUIExtension installer.wxs
light -ext WixUIExtension -out "Scar Chat.msi" installer.wixobj

Development Progress

See PROGRESS.md for detailed feature implementation status and dependencies.

License

[Specify your license here]

Contributing

[Contribution guidelines if applicable]

Troubleshooting

Linux: Missing Pipewire/Portal

Ensure pipewire and xdg-desktop-portal-hyprland (or appropriate portal) are installed and running:

systemctl --user status pipewire

Windows: FFmpeg not found

Add FFmpeg library paths to CMake:

cmake -DFFMPEG_ROOT=/path/to/ffmpeg ..

SSL Certificate Errors

Generate self-signed certificates for testing:

openssl req -x509 -newkey rsa:4096 -keyout server.key -out server.pem -days 365 -nodes

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Project Status: In Development - See PROGRESS.md for current milestone