DCS Lua Runner GUI

A standalone Windows GUI application for executing Lua code in DCS World, replacing the need for VSCode extension or web interface.

⚠️ SECURITY WARNING ⚠️

CRITICAL: This application requires DCS desanitization and may expose your system to significant security risks. Please read all warnings before proceeding.

Major Security Risks

🔓 DCS Desanitization Risks

• Removes DCS security restrictions - Allows unrestricted Lua execution
• Full system access - Scripts can access files, network, and system functions
• No sandboxing - Malicious code can damage your system or steal data
• Persistent changes - Effects remain until manually reverted

🌐 Network Exposure Risks

• Opens network ports - DCS Fiddle server listens on network interfaces
• Remote code execution - Anyone with access can run arbitrary Lua code on your system
• Credential vulnerabilities - Weak authentication may be bypassed
• Data exposure - Mission files and system information may be accessible remotely

⚡ DCS Fiddle Specific Risks

• Unrestricted API access - Full DCS scripting environment exposure
• Mission interference - Can affect running missions and multiplayer sessions
• Performance impact - May cause DCS instability or crashes
• Log exposure - Sensitive information may be logged or transmitted

🛡️ Risk Mitigation

ONLY proceed if you:

• ✅ Understand the security implications completely
• ✅ Trust all code you plan to execute
• ✅ Use on isolated systems (not production/online gaming PCs)
• ✅ Have proper backups of your DCS installation
• ✅ Use strong authentication for remote access
• ✅ Restrict network access (firewall rules, VPN-only access)
• ✅ Monitor system activity when running unknown scripts

⛔ DO NOT USE if:

• ❌ You don't understand the technical implications
• ❌ Your Sever contains sensitive personal/work data
• ❌ You plan to run untrusted code from others
• ❌ You use the same PC for online banking/shopping

Features

• Lua Code Editor: Syntax highlighting and line numbers for Lua code
• Local/Remote Execution: Run code on local DCS instance or remote servers
• Environment Support: Execute in Mission or GUI scripting environments
• Authentication: Username/password authentication for remote servers
• Result Formatting: Display results as Lua tables or JSON
• Settings Persistence: Save and load connection settings
• File Operations: Open, save, and manage Lua files

Based On

This application replicates the functionality of:

• DCS Lua Runner VSCode Extension
• DCS Fiddle Web Interface

Requirements

• Python 3.7 or higher
• DCS World with DCS Fiddle server script installed
• Required Python packages (see requirements.txt)

Installation

Option 1: Windows Executable (Recommended)

1. Download the latest release from the DCS_Lua_Runner_GUI_v1.0 folder
2. Double-click DCS_Lua_Runner_GUI.exe to start the application
3. Setup DCS Fiddle Server: Follow the DCS setup instructions below

Option 2: Run from Python Source

1. Clone or Download this repository
2. Install Python dependencies:

   pip install -r requirements.txt

3. Run the application:

   python main.py

4. Setup DCS Fiddle Server: Follow the DCS setup instructions below

DCS Setup

⚠️ CRITICAL SECURITY NOTICE ⚠️

The following steps will DISABLE DCS security protections. This creates serious security vulnerabilities:

• 🔥 REMOVES SANDBOXING - Scripts gain full system access
• 💾 FILE SYSTEM ACCESS - Can read/write/delete any files on your computer
• 🌐 NETWORK ACCESS - Can make network connections to any server
• ⚙️ SYSTEM COMMANDS - Can execute system commands and programs
• 🔓 PERSISTENT CHANGES - Security remains disabled until manually restored

💡 SECURITY BEST PRACTICES:

• 🔒 Backup your DCS installation before proceeding
• 🏠 Use on isolated/offline systems only
• 👀 Review ALL code before execution - never run untrusted scripts
• 🔐 Use strong passwords for remote access
• 🚪 Disable when not needed - re-enable sanitization after use
• 📊 Monitor system activity while running scripts

Installation Steps

You need to install the DCS Fiddle server script in your DCS installation:

1. Download the dcs-fiddle-server.lua script (included in this repository)
2. Copy to %USERPROFILE%\Saved Games\<DCS VERSION>\Scripts\Hooks\
3. ⚠️ De-sanitize Mission Scripting (edit DCS_INSTALL\Scripts\MissionScripting.lua):

   do
       sanitizeModule('os')
       sanitizeModule('io')
       sanitizeModule('lfs')
   --  _G['require'] = nil      -- ⚠️ SECURITY: This enables require() function
       _G['loadlib'] = nil
   --  _G['package'] = nil      -- ⚠️ SECURITY: This enables package loading
   end

🔄 TO RESTORE SECURITY: Uncomment these lines (remove --) when finished:

_G['require'] = nil     -- Restore this line to disable require()
_G['package'] = nil     -- Restore this line to disable package loading

Remote Access Configuration

🚨 EXTREME SECURITY RISK 🚨

Enabling remote access creates MAXIMUM SECURITY EXPOSURE:

• 🌍 INTERNET ACCESSIBLE - Your PC becomes accessible from anywhere on the network/internet
• 💻 REMOTE CODE EXECUTION - Anyone with credentials can run ANY Lua code on your system
• 🔓 UNSECURED BY DEFAULT - Basic authentication is easily bypassed or bruted
• 📊 DATA EXFILTRATION - All DCS data, logs, and accessible files can be stolen
• 🎯 ATTACK VECTOR - Creates entry point for malicious actors

🛡️ MANDATORY SECURITY MEASURES:

1. 🔥 FIREWALL RULES - Block port 12080 from internet, allow only specific IPs
2. 🔐 STRONG CREDENTIALS - Use complex passwords (20+ characters, mixed case, numbers, symbols)
3. 🏠 LOCAL NETWORK ONLY - Never expose to internet (BIND_IP = '127.0.0.1' for local only)
4. 📱 VPN ACCESS - Use VPN for remote access instead of direct exposure
5. ⏰ TIME LIMITS - Disable when not actively needed
6. 👀 MONITORING - Watch logs for unauthorized access attempts

⚠️ CONFIGURATION OPTIONS:

-- SAFER: Local access only (recommended)
FIDDLE.BIND_IP = '127.0.0.1'  -- Local computer only
FIDDLE.PORT = 12080           

-- DANGEROUS: Network/Internet access (high risk)
FIDDLE.BIND_IP = '0.0.0.0'    -- ⚠️ EXPOSES TO NETWORK/INTERNET
FIDDLE.PORT = 12080           

-- MANDATORY: Strong authentication
FIDDLE.AUTH = true                    -- ⚠️ NEVER set to false
FIDDLE.USERNAME = 'ComplexUsername123'    -- Use unique, complex username  
FIDDLE.PASSWORD = 'VeryLongComplexPassword456!'  -- 20+ character password

🔴 NEVER DO THIS:

FIDDLE.AUTH = false           -- ⚠️ NEVER disable authentication
FIDDLE.PASSWORD = 'password'  -- ⚠️ NEVER use weak passwords

Usage

1. Run the application:

   python main.py or launch DCS_Lua_Runner_GUI.exe

2. Configure connection settings in the Settings tab:

   • Server address and port
   • Authentication credentials
   • Execution environment preferences
   • IMPORTANT: Click "Save Settings" after entering all connection details to persist your configuration

3. Write or load Lua code in the editor

4. Execute code using:

   • F5 - Run all code
   • F8 - Run selected code
   • Toolbar buttons
   • Menu options

5. View results in the Results tab with syntax highlighting

Interface Overview

Toolbar

• 📁 Load File: Load Lua file with options (replace, append, or insert at cursor)
• ▶ Run: Execute all code in editor
• ▶ Selected: Execute selected code only
• Local/Remote: Toggle execution target
• Mission/GUI: Toggle DCS environment
• Lua/JSON: Toggle result format

Settings Tab

• Connection Settings: Server address, ports, HTTPS
• Authentication: Username and password for remote access
• Execution Settings: Local/remote and environment toggles
• Display Settings: Result format preferences

Code Editor

• Syntax highlighting for Lua code
• Line numbers
• Standard editing features (cut, copy, paste, undo)
• File operations (new, open, save)

Results Tab

• Timestamped execution results
• Syntax highlighting for results
• Success/error indication
• Scrollable output with clear option

Keyboard Shortcuts

• Ctrl+N - New file
• Ctrl+O - Open file
• Ctrl+S - Save file
• Ctrl+Shift+S - Save as
• F5 - Run code
• F8 - Run selected code
• Ctrl+X - Cut
• Ctrl+C - Copy
• Ctrl+V - Paste
• Ctrl+A - Select all

Example Lua Code

-- Get mission information
local mission_time = timer.getTime()
local theatre = env.mission.theatre

-- Get player information
local player = world.getPlayer()
if player then
    local pos = player:getPosition().p
    return {
        mission_time = mission_time,
        theatre = theatre,
        player_name = player:getName(),
        player_position = {
            x = pos.x,
            y = pos.y,
            z = pos.z
        }
    }
else
    return {
        mission_time = mission_time,
        theatre = theatre,
        message = "No player found"
    }
end

Configuration File

Settings are automatically saved to dcs_lua_runner_settings.json in the application directory. This includes:

• Connection settings
• Authentication credentials
• Window size and preferences
• Execution defaults

Troubleshooting

Connection Issues

• Verify DCS Fiddle server is running
• Check server address and port settings
• Ensure firewall allows connections (for remote access)
• Verify authentication credentials

Script Errors

• Check Lua syntax in the editor
• Verify DCS environment (Mission vs GUI)
• Check DCS logs for detailed error information

Installation Issues

• Ensure Python 3.7+ is installed
• Install dependencies: pip install -r requirements.txt
• Run from the correct directory

License

MIT License - Based on the original DCS Fiddle project by JonathanTurnock and john681611.

Credits

• Original DCS Fiddle: JonathanTurnock and john681611
• DCS Lua Runner VSCode Extension: omltcat
• GUI Implementation: Created for standalone Windows application