C Proxy Server

A lightweight and efficient proxy server implementation in C, supporting both Linux and Windows platforms. This proxy server can handle HTTP/HTTPS requests and includes features like request logging, SSL/TLS support, and configurable port settings.

Project Structure

04_Finalize/
├── Linux/
│   ├── proxy.c          # Main proxy server source code
│   ├── server.crt       # SSL certificate
│   ├── server.key       # SSL private key
│   └── proxy_log.txt    # Log file
└── windows/
    ├── WinProxy.c       # Windows-specific proxy server code
    ├── proxy.exe        # Compiled Windows executable
    └── proxy_log.txt    # Log file

Prerequisites

Linux

• GCC compiler
• OpenSSL development libraries
• Make build system

Windows

• MinGW-w64 or MSVC compiler
• OpenSSL development libraries
• Windows 10 or later

Building and Running

Linux

1. Navigate to the Linux directory:

   cd Linux

2. Compile the proxy server:

   gcc -o proxy_server proxy.c -lssl -lcrypto

3. Run the proxy server:

   ./proxy_server

4. To run in the background:

   ./proxy_server &

The server will start on port 8080 by default. You can configure your browser to use this proxy server by setting:

• Proxy address: 127.0.0.1
• Port: 8080

For Firefox:

1. Go to Settings > Network Settings
2. Select "Manual proxy configuration"
3. Enter HTTP Proxy: 127.0.0.1
4. Enter Port: 8080
5. Click OK

For Chrome:

1. Go to Settings > Advanced > System
2. Click "Open your computer's proxy settings"
3. Enter HTTP Proxy: 127.0.0.1
4. Enter Port: 8080
5. Click Save

Windows

1. Navigate to the windows directory:

   cd windows

2. You can either:

   • Use the pre-compiled proxy.exe directly
   • Or compile from source using MinGW-w64:

     gcc -o proxy.exe WinProxy.c -lssl -lcrypto

3. Run the proxy server:

   proxy.exe

The server will start on port 8080 by default. Configure your browser's proxy settings as mentioned above.

Features

• HTTP/HTTPS proxy support
• SSL/TLS encryption
• Request logging
• Configurable port settings
• Cross-platform compatibility
• Error handling and recovery

Logging

Both Linux and Windows versions maintain logs in their respective proxy_log.txt files. The logs include:

• Connection attempts
• Request details
• Error messages
• SSL/TLS handshake information

Security Notes

• The included SSL certificates are for development purposes only
• For production use, replace server.crt and server.key with your own certificates
• Always use HTTPS for sensitive data transmission

Troubleshooting

1. If the server fails to start:

   • Check if port 8080 is already in use
   • Verify SSL certificate permissions
   • Ensure all required libraries are installed

2. If connections fail:

   • Verify proxy settings in your browser
   • Check firewall settings
   • Review the log file for error messages

License

This project is open source and available under the MIT License.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.