Firefly Go Proxy

A lightweight HTTP/HTTPS proxy server with domain redirection and request blocking capabilities. This tool is designed to help with local development and testing by intercepting and modifying HTTP/HTTPS traffic.

Features

• HTTP/HTTPS proxy with MITM support
• Domain-based request redirection
• URL pattern blocking
• Automatic certificate management
• Cross-platform support (Windows, macOS, Linux)
• System proxy configuration
• Automatic admin prompt on macOS/Linux for certificate/proxy setup

Installation

Prerequisites

• Go 1.22 or higher
• Git

Building from source

cd firefly-go-proxy
go build

Usage

Basic usage

./firefly-proxy [flags] //linux|macos
./firefly-proxy.exe [flags] //windows

Available Flags

• -r: Redirect target host (default: "127.0.0.1:21000")
• -b: Comma-separated list of blocked ports
• -p: Proxy listen port (default: auto)
• -e: Path to an executable to run with admin privileges

Examples

1. Start proxy with default settings:

   ./firefly-proxy //linux|macos
   ./firefly-proxy.exe //windows
   

2. Redirect traffic to a different host:

   ./firefly-proxy -r 192.168.1.100:8080 //linux|macos
   ./firefly-proxy.exe -r 192.168.1.100:8080 //windows
   

3. Block specific ports:

   ./firefly-proxy -b "80,443,8080" //linux|macos
   ./firefly-proxy.exe -b "80,443,8080" //windows
   

4. Run an executable with admin privileges:

   ./firefly-proxy -e "/path/to/your/executable" //linux|macos
   ./firefly-proxy.exe -e "/path/to/your/executable" //windows
   

5. Start proxy on a specific port:

   ./firefly-proxy -p 8888 //linux|macos
   ./firefly-proxy.exe -p 8888 //windows
   

   On macOS/Linux, if the proxy is not already running as root, it relaunches with an administrator prompt. On Linux, logs from the elevated process are written to /tmp/firefly-go-proxy.log; on macOS, elevated process output is discarded.

How it works

The proxy intercepts HTTP/HTTPS traffic and can:

• Redirect requests based on domain names
• Block specific URLs or patterns
• Handle SSL/TLS connections with custom CA certificates
• Automatically configure system proxy settings

License

MIT License