Caddy Defender Plugin

The Caddy Defender plugin serves as an essential middleware for the Caddy web server, designed to enhance security by allowing users to block or manipulate incoming requests based on their client's IP address. This functionality is particularly beneficial in mitigating unwanted traffic and safeguarding against the use of website data for AI training purposes by returning disruptive responses.

Features

• IP Range Filtering: Control access by blocking or manipulating requests from specific IP ranges.
• Embedded IP Ranges: Use predefined IP ranges associated with popular AI services, including OpenAI, DeepSeek, and GitHub Copilot, without any additional configuration.
• Custom IP Ranges: Flexibly configure personalized IP ranges through the Caddyfile.
• Multiple Responder Backends: Choose from various response options:
  • Block: Issue a 403 Forbidden response to denied requests.
  • Garbage: Provide nonsensical data to hinder AI training efforts.
  • Custom: Deliver a tailored message to users, based on configuration.

Configuration Examples

The defender directive allows for straightforward configuration in the Caddyfile:

defender <responder> {
    message <custom message>
    range <ip_ranges...>
}

Block Requests

To block requests from specific IP address ranges:

localhost:8080 {
    defender block {
        range 203.0.113.0/24 openai 198.51.100.0/24 
    } 
    respond "Hello, world!"  # what humans see
}

Return Garbage Data

To return garbage data for requests from certain IP ranges:

localhost:8081 {
    defender garbage {
        range 192.168.0.0/24 
    }
    respond "Hello, world!"  # what humans see
}

Custom Response

To return a custom message for specific IP ranges:

localhost:8082 {
    defender custom {
        message "Custom response message"
        range 10.0.0.0/8
    } 
    respond "Hello, world!"  # what humans see
} 

Embedded IP Ranges

The plugin comes with predefined embedded IP ranges for popular AI services, facilitating instant usage without extra setup. Key services include:

Contributing

Contributions to enhance the plugin are encouraged. Options include:

• Adding New IP Ranges: Create a new fetcher within the ranges/fetchers package as detailed in the Contributing Guide.
• Adding a New Responder: Implement a new responder in the responders package, updating the UnmarshalCaddyfile method to accommodate this addition by following guidelines in the Contributing Guide.

Acknowledgments

This project drew inspiration from community discussions and is built with care using the Caddy platform.