4InARow

Project for the Foundations of Cybersecurity course of the Master of Science in Computer Engineering, University of Pisa.

The project consists in the design and implementation of a secure online version of Four in a Row, written in C++. The communications are confidential, authenticated and protected against replay attacks. For more details, please refer to the documentation.

Overview

The repository is organised in the following way:

• src/client contains the client application.
• src/crypto contains the cryptographic library.
• src/exception contains the custom exceptions used in the code.
• src/game contains the manager of the game board and the player class.
• src/message contains the messages exchanged between parties.
• src/server contains the server application.
• src/socket contains the networking library.
• src/utils contains utility functions and constants.

Requirements

• A Unix-like OS. The code has been tested on Ubuntu 20.04.3 LTS.
• A C++ compiler supporting C++14.
• CMake 3.16+. Older versions should work too (not tested).
• OpenSSL 1.1.1+. The most recent version of OpenSSL can be installed running:

  sudo apt-get install libssl-dev

Installation and execution

A user is registered if its RSA-2048 private-public key pair is stored in src/client/keys and the same public key is stored in src/server/players. The file names must follow the pattern username + _pubkey.pem/_privkey.pem. All the provided private keys have password unipi, which is asked at runtime.

To execute the application:

• Inside the root folder, create a compilation directory, for example called build-dir:

  mkdir build-dir

• Go inside the folder and compile the project:

  cd build-dir
  cmake ..
  make -C src/server/ all
  make -C src/client/ all

• Start the server, choosing a private IPv4 address:

  cd src/server
  ./server --address 127.0.0.1

• Run another shell and start the first client, choosing a private IPv4 address:

  cd src/client
  ./client --username Alice --client 127.0.0.2 --server 127.0.0.1

• Run another shell and start the second client, choosing a private IPv4 address:

  cd src/client
  ./client --username Bob --client 127.0.0.3 --server 127.0.0.1

• Play!

The application uses the ports 5000 and 5001. If necessary, they can be changed by modifying the variables SERVER_PORT and PLAYER_PORT in src/utils/Constants.cpp.