Multithreaded Proxy Server

RebelGate, is a multithreaded reverse proxy server that can handle multiple client requests concurrently using C++ threads. It includes features like request forwarding, token-based authorization, rate limiting, and logging.
Skills Demonstrated: Multithreading, Network Programming, Sockets, HTTP Proxying, Authorization, Logging.

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Overview

This project implements a reverse proxy server in C++. The server listens for HTTP requests on a specified port, validates them using a bearer token, applies per-IP rate limiting, and forwards authorized requests to a backend server. Unauthorized or too-frequent requests are rejected with appropriate HTTP status codes. All activity is logged for debugging and monitoring purposes.

Note: This version is designed for Windows using Winsock. It can be adapted for POSIX-based systems with minor changes.

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Project Structure

• CMakeLists.txt: Configuration file for building the project with CMake.
• include/proxy.h: Header file declaring the ProxyServer class.
• include/auth.h: Header file for token validation and rate limiting functions.
• include/logger.h: Header file for the request logger.
• src/main.cpp: Main entry point of the application.
• src/proxy.cpp: Core logic for accepting connections and forwarding requests.
• src/auth.cpp: Checks authorization token and applies rate-limiting logic.
• src/logger.cpp: Logs request metadata to rebelgate.log.
• README.md: Documentation file for the project.

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Key Features

• Multithreading: Handles multiple client connections concurrently using std::thread.
• Authorization: Only requests with a valid bearer token are forwarded.
• Rate Limiting: Limits requests per IP to avoid abuse (1 request every 2 seconds).
• Proxy Forwarding: Forwards valid requests to a backend server.
• Logging: All requests (IP, method, path, status) are logged to a local file.
• Modular Design: Code is cleanly organized into headers and implementation files.

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Building the Project

To build the project, follow these steps:

1. Clone the Repository:

   git clone https://github.com/Tomajari/Multithreaded-Proxy-Server.git
   cd Multithreaded-Proxy-Server

2. Create a Build Directory:

   mkdir build
   cd build

3. Generate Build Files with CMake:

   cmake ..

4. Compile the Project:

   cmake --build .

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Running the Proxy Server

After building the project, you can run the proxy server with the following command:

./Multithreaded-Proxy-Server

The server will start and listen for incoming connections on the specified port (default is 8080). You can modify the port in src/main.cpp.

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Testing the Proxy Server

To test the server, you can use tools like curl or a web browser:

• Valid Requests: Send a request with a valid bearer token to the proxy server. The request will be forwarded to the backend server.
• Unauthorized Requests: Requests without a valid token will receive a 403 Forbidden response.
• Rate-Limited Requests: Excessive requests from the same IP will receive a 429 Too Many Requests response.

Example using curl:

curl -H "Authorization: Bearer secret-token" http://localhost:8080

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Customization

• Port Number: Change the port number in src/main.cpp to any available port.
• Backend Server: Update the backend server's IP and port in src/main.cpp.
• Rate Limiting: Modify the rate-limiting logic in src/auth.cpp to adjust the request limits.
• Logging: Customize the log format or file location in src/logger.cpp.

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Troubleshooting

• Port Already in Use: If you encounter a bind failed: Address already in use error, ensure no other process is using the specified port, or change the port number.
• Backend Server Unreachable: If the proxy server cannot connect to the backend server, verify the backend server's IP and port.
• File Permissions: Ensure the application has write permissions for the logs/ directory.

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License

This project is licensed under the MIT License. See the LICENSE file for details.