FazelHaghighi / os-uni-course

Operating Systems Course Project at BNUT University, Fall Semester 1402.

Operating Systems Course Project — Server, Client, Worker Architecture

How to Run

Running the Server

Please ensure Python is installed on your system before attempting to run the server.

1. Open terminal in the directory where the OS-course project folder is located.
2. Execute the run command:

python server.py

Running the Client

1. Open another terminal for the client.
2. Execute the client command:

python client.py

Project Description

This project is designed to manage a set of server, client, and worker processes to maintain file integrity across university servers.

Step One

Objective: Implement a system that verifies file integrity to detect any unintended alterations.

Process Implementation:

• Server Process: Initiates one server process and five worker processes.
  • Server creates a new worker if one exits due to an error.
  • Server awaits connections from client and worker processes.
• Client Process:
  • Upon connection, clients send the server several file addresses.
• Worker Process:
  • Connects to the server to receive file addresses.
  • Assigned a maximum of five file addresses per request.
  • Workers calculate the MD5 checksums of received files and save them with a .md5 extension.
  • After processing, workers seek new files to process.
• Communication: Utilises network sockets or pipes for process communication.
• MD5 Calculation: Can use available library code or internet snippets.
• Testing: Employ client processes to gradually supply the server with a substantial number of file addresses.

Step Two — Expanding the Client Program

First Part:

• The client program now runs six concurrent threads.
  • One thread performs a recursive system file listing.
  • Five threads validate the listed files, each responsible for a unique file to prevent overlap.
  • Checker threads request file addresses, with synchronization to avoid race conditions when contacting the server.

Second Part — Identifying Malicious Workers:

• Workers with a file MD5 mismatch incur penalties.
• Workers accumulating over two warnings are terminated.
• The server must always maintain five operational workers, replacing as necessary.
• Log all activity, particularly penalties and worker terminations.
• Automate the testing process.