Killswitch Script

This tool provides an IP-based killswitch using iptables to block outgoing traffic if your public IP changes. It also allows you to configure VPN traffic, block or unblock specific IP addresses, and monitor real-time IP changes. The script is customizable and can save/load configurations for easy use.

Installation

To install and run the killswitch tool, execute the following command in your terminal:

bash <(curl -Ls https://raw.githubusercontent.com/samankhalife/killswitch/refs/heads/main/install.sh)

Note: Make sure that curl is installed on your system. If not, you can install it using the following command:

• On Ubuntu/Debian: sudo apt-get install curl
• On CentOS/RedHat: sudo yum install curl

Features and Usage

The script provides an interactive menu where you can choose the following options:

1. Activate killswitch:
   Activate the killswitch and block all traffic if your public IP changes.

2. Deactivate killswitch:
   Remove the killswitch and allow traffic as normal.

3. View iptables rules:
   Display the current iptables rules to see active traffic restrictions.

4. Block an IP:
   Manually block outgoing traffic to a specific IP address.

5. Unblock an IP:
   Remove the block for a specific IP address.

6. Configure VPN interface:
   Set your VPN interface (e.g., tun0) to allow VPN traffic while the killswitch is active.

7. View available network interfaces:
   List all available network interfaces on your system.

8. Monitor IP changes:
   Monitor real-time IP changes and activate the killswitch automatically if your public IP changes.

9. Save current configuration:
   Save the current IP and VPN interface settings to a configuration file (killswitch.conf).

10. Load saved configuration:
    Load a previously saved configuration to restore your killswitch settings.

11. Exit:
    Exit the script.

Commands via Menu

You can choose options either by typing the number or by entering the associated keyword:

• Example: Type 1 or activate to activate the killswitch.

Example Use Case

1. Activate the killswitch:
   Run the script:

   killswitch

   Select option 1 or type activate.

2. Block a specific IP:
   Choose option 4, then enter the IP address you want to block.

3. Monitor IP changes:
   Enable real-time monitoring by selecting option 8. If your public IP changes, the killswitch will automatically engage.

4. Save the configuration:
   Use option 9 to save your current IP and VPN interface settings for future use.

Configuration

The script saves the following settings in the killswitch.conf file:

• MY_IP: Your current public IP address, used for blocking traffic if it changes.
• VPN_INTERFACE: The VPN interface to allow traffic when the killswitch is active.

Loading Saved Configuration

To load the saved configuration:

killswitch

Then select option 10 or type load to apply the previously saved settings.

Troubleshooting

If you encounter any issues with the killswitch, ensure that:

• Your iptables is properly configured.
• The killswitch.conf file has been correctly saved.
• You have the necessary permissions to execute the script (use chmod +x killswitch.sh if needed).