About A3Guard • Key Features • Installation • Usage • Security • Contributing • License

About A3Guard

A3Guard is a comprehensive C++/Qt5-based desktop application for advanced assessment and monitoring for academic environments. It provides robust security features, real-time monitoring, and minimal resource usage.

Features

Core Monitoring

• Application Tracking: Monitor launched/closed applications
• Window Focus Tracking: Track active window changes
• Clipboard Monitoring: Detect copy/paste activities
• USB Monitoring: Detect device insertions/removals
• Network Control: Granular network interface management

Security

• AES-256 Encryption: All logs and screenshots encrypted
• File Integrity Checking: Detect tampering with SHA-256 hashes
• Secure Deletion: Multi-pass file overwriting
• Administrator Privileges: Root-level system access required
• Real-time Alerts: Visual and audio violation notifications

Performance

• Minimal Resource Usage: <10% CPU, <100MB RAM
• Optimized Monitoring: Efficient polling intervals
• Resource Monitoring: Self-monitoring with limits
• Custom File Extensions: .a3log, .a3img, .a3bak, .a3int

Requirements

System Requirements

• Ubuntu 20.04 or newer
• Qt5 development libraries
• OpenSSL
• X11 with XFixes
• Root/sudo access

Build Dependencies

sudo apt-get install -y \
    build-essential \
    cmake \
    qtbase5-dev \
    qtbase5-dev-tools \
    libssl-dev \
    libudev-dev \
    libx11-dev \
    libxfixes-dev \
    pkg-config

Runtime Dependencies

sudo apt-get install -y \
    qt5-default \
    libqt5widgets5 \
    libqt5core5a \
    libqt5gui5 \
    libqt5network5 \
    libssl1.1 \
    libudev1 \
    libx11-6 \
    libxfixes3 \
    gksu

Building

Quick Build

# Clone or extract source
mkdir -p build
cd build
cmake ..
make -j$(nproc)

Detailed Build Process

# Install build dependencies
sudo apt-get update
sudo apt-get install -y build-essential cmake qtbase5-dev qtbase5-dev-tools \
    libssl-dev libudev-dev libx11-dev libxfixes-dev pkg-config

# Create build directory
mkdir -p build && cd build

# Configure with CMake
cmake -DCMAKE_BUILD_TYPE=Release ..

# Build (use all CPU cores)
make -j$(nproc)

# Optional: Build Debian package
cpack -G DEB

Build Options

• -DCMAKE_BUILD_TYPE=Release: Optimized release build (default)
• -DCMAKE_BUILD_TYPE=Debug: Debug build with symbols

Installation

Automated Installation

# Build first
mkdir -p build && cd build
cmake .. && make

# Install (requires root)
cd ..
sudo ./scripts/install.sh

Manual Installation

# After building
sudo mkdir -p /opt/a3guard/bin
sudo cp build/A3Guard /opt/a3guard/bin/
sudo cp config/a3guard.conf /etc/a3guard/
sudo cp scripts/install.sh /opt/a3guard/scripts/

# Run installation script
sudo ./scripts/install.sh

Package Installation

# Build package
cd build
cpack -G DEB

# Install package
sudo dpkg -i a3guard-*.deb
sudo apt-get install -f  # Fix dependencies if needed

Usage

GUI Mode

# Launch with GUI (requires root)
sudo a3guard

# Or use desktop launcher (requires authentication)
a3guard

Service Mode

# Start service
sudo systemctl start a3guard

# Enable auto-start
sudo systemctl enable a3guard

# Check status
sudo systemctl status a3guard

# View logs
sudo journalctl -u a3guard -f

Command Line Options

A3Guard [options]

Options:
  --daemon          Run as daemon (no GUI)
  --generate-key    Generate new encryption key
  --verify-integrity Verify file integrity
  --config <file>   Use custom config file
  --help           Show help
  --version        Show version

Configuration

Configuration file: /etc/a3guard/a3guard.conf

Key Settings

[monitoring]
network_check_interval=30      # Check network every 30 seconds
app_monitor_interval=5         # Check apps every 5 seconds

[security]
enable_integrity_check=true    # Enable file integrity checking
encryption_key_file=/etc/a3guard/a3guard.key

[resources]
max_cpu_usage=10              # Maximum 10% CPU usage
max_memory_usage=100          # Maximum 100MB RAM

[network]
disable_interfaces=wifi,bluetooth,ethernet
block_all_traffic=true

Security Features

Encryption

• Algorithm: AES-256-CBC
• Key Storage: Secure file with 600 permissions
• Data Protection: All logs and screenshots encrypted

Integrity Checking

• Hash Algorithm: SHA-256
• Real-time Monitoring: File system watcher
• Periodic Verification: Configurable intervals
• Violation Detection: Automatic alerts

Access Control

• Root Privileges: Required for system-level monitoring
• AppArmor Profile: Optional additional security layer
• Secure Permissions: Restricted file access
• Process Protection: Systemd service hardening

File Structure

Installation Paths

/opt/a3guard/          # Application directory
├── bin/
│   └── A3Guard        # Main executable
└── scripts/
    ├── install.sh       # Installation script
    ├── uninstall.sh     # Removal script
    └── build.sh         # Build script

/etc/a3guard/          # Configuration directory
├── a3guard.conf       # Main configuration
└── a3guard.key        # Encryption key (auto-generated)

/var/log/a3guard/      # Log directory
└── *.a3log              # Encrypted log files

/var/lib/a3guard/      # Data directory
├── backup/
│   └── *.a3bak          # Backup files
└── integrity/
    └── *.a3int          # Integrity check files

Custom Extensions

• .a3log - Encrypted log files
• .a3bak - Encrypted backup files
• .a3int - Encrypted integrity check files

Monitoring Capabilities

Application Monitoring

• Process launch/termination detection
• Window title and class tracking
• Active window focus changes
• Resource usage per application

System Monitoring

• USB device insertion/removal
• Network interface state changes
• Clipboard content changes (hashed)
• System resource usage

Network Control

• Wi-Fi interface control
• Bluetooth interface control
• Ethernet interface control
• Traffic blocking with iptables
• NetworkManager integration

Troubleshooting

Common Issues

Permission denied errors:

# Ensure proper permissions
sudo chown -R root:a3guard /var/log/a3guard /var/lib/a3guard
sudo chmod 700 /var/log/a3guard /var/lib/a3guard

Build failures:

# Install all dependencies
sudo apt-get build-dep qt5-default
sudo apt-get install qtbase5-private-dev

Service won't start:

# Check systemd logs
sudo journalctl -u a3guard -n 50

# Verify binary permissions
sudo chmod +x /opt/a3guard/bin/A3Guard

GUI won't launch:

# Check X11 permissions
sudo xhost +SI:localuser:root

# Use pkexec instead of gksu
pkexec /opt/a3guard/bin/A3Guard

Debug Mode

# Build debug version
cd build
cmake -DCMAKE_BUILD_TYPE=Debug ..
make

# Run with debug output
sudo ./A3Guard --verbose

Log Analysis

# View decrypted logs (requires root)
sudo a3guard --decrypt-logs

# Check integrity
sudo a3guard --verify-integrity

# Resource usage
sudo a3guard --resource-report

Uninstallation

# Using uninstall script
sudo /opt/a3guard/scripts/uninstall.sh

# Manual removal
sudo systemctl stop a3guard
sudo systemctl disable a3guard
sudo rm -rf /opt/a3guard
sudo rm -rf /etc/a3guard
sudo rm -rf /var/log/a3guard
sudo rm -rf /var/lib/a3guard
sudo rm -f /etc/systemd/system/a3guard.service
sudo rm -f /usr/share/applications/a3guard.desktop
sudo rm -f /usr/local/bin/a3guard
sudo userdel a3guard

Development

Code Structure

• src/: Source files (.cpp)
• include/: Header files (.h)
• config/: Configuration files
• scripts/: Installation/build scripts
• resources/: Qt resources (icons, etc.)

Key Classes

• SecurityManager: Encryption and integrity
• MonitoringEngine: Core monitoring logic
• NetworkManager: Network control
• ConfigManager: Configuration handling
• MainWindow: GUI interface

Building from Source

# Development build with debug symbols
mkdir debug-build && cd debug-build
cmake -DCMAKE_BUILD_TYPE=Debug ..
make

# Profile-guided optimization build
mkdir pgo-build && cd pgo-build
cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_CXX_FLAGS="-fprofile-generate" ..
make && ./A3Guard --benchmark
cmake -DCMAKE_CXX_FLAGS="-fprofile-use" ..
make

License

This project is licensed under a proprietary license for educational use. See LICENSE file for details.

Support

For support and bug reports:

• Check logs: /var/log/a3guard/
• Verify integrity: sudo a3guard --verify-integrity
• Review configuration: /etc/a3guard/a3guard.conf

Security Considerations

⚠️ Important Security Notes:

• Always run integrity checks after system updates
• Regularly backup encryption keys securely
• Monitor log files for unauthorized access attempts
• Use AppArmor/SELinux for additional security layers
• Keep the system updated with latest security patches

Performance Tuning

For optimal performance on exam systems:

• Adjust monitoring intervals based on exam duration
• Configure resource limits appropriately
• Use SSD storage for better I/O performance
• Disable unnecessary system services during exams