TROME

Trome was created and submitted as part of the Magshimim National Cyber Program 2nd year final project by Itay Herskovits and Stav Solomon.

📚 Table of Contents

• 📌 Features
• 🎁 Bonuses
  • ✅ Official
  • 🛠️ Custom
• 🧰 Installation & Setup
• 🏗️ Server Infrastructure
  • 🧠 State Management
    • 📍 States
    • 🔁 Transitions
  • 🧩 Codec Model
    • 📬 Message Structure (Protocol)
    • 🧾 Request
    • 🧾 Response
    • 📦 Body Content
    • 📡 Notifications System
• 🔐 Cryptography Overview
  • 🔑 Current Encryption Method: RSA (Asymmetric)
  • 🛠 Other Encryption Method
    • 🟡 AES (Advanced Encryption Standard)
    • 🟡 OTP (One-Time Pad)

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📌 Features

• Cross-platform server & client
• 2 Gamemodes
  • Trivia Rush
  • Head-to-Head
• User-defined questions
• Player kicking
• BGM !!

🎁 Bonuses

Features explicitly deemed as a bonus by Magshimim, as well as additional, custom ones we simply wanted to add:

✅ Official

• Regexes
  • Signup validation with regexes using the Compile Time Regular Expressions library
• Singletons
  • The transformation of the following classes to use the Singleton pattern:
    • Server
    • Database
    • CommonCommunicator
    • WindowsCommunicator
    • UnixCommunicator
  • The transformation of the following classes to use the Static Class pattern:
    • JsonRequestPacketDeserializer
    • JsonResponsePacketSerializer
• MongoDB
• Pulling questions from OpenTDB into the database
• User-defined questions
• Head-to-Head gamemode
  • Pre-game countdown
• Cryptography
  • OTP
  • Crypto++
    • RSA
    • AES

🛠️ Custom

• CMake-aligned project
• Cross-platform support for Windows/Unix
• Notifications system
• Avalonia UI
  • MVVM
  • ReactiveUI
• Harmonically syncing BGM w/ NAudio
• Viewing player statistics in-game
• Player kicking
• SQLite Prepared Statements & Bindings

🧰 Installation & Setup

First, clone this repository:

git clone https://gitlab.com/Tomgluz/Trivia_Itay_Stav_2025.git

🖥️ Server Setup

📦 Dependencies

🪟 Windows

Install VCPKG directly under your C drive:

cd C:\

# Clone the repository
git clone https://github.com/microsoft/vcpkg.git

# Run the bootstrap script
cd vcpkg; .\bootstrap-vcpkg.bat

When done, run the following command to install all required dependencies:

.\vcpkg install openssl cryptopp

Note

If you're using MongoDB, also run:

.\vcpkg install mongo-cxx-driver

🐧 Unix

Install the following development packages:

• OpenSSL
• Crypto++
• If using MongoDB: MongoDB C++ Driver

Note

Package names may vary depending on your package manager and distribution.

🏗️ Building

In the project directory, under Server:

• If a build directory is not present, create one.
• CD into it.

cmake ../
cmake --build ./

🌿 Using MongoDB (Optional)

Note

Using MongoDB will replace the usage of Sqlite.

Look for the following line in CMakeLists.txt, and switch the OFF statement to an ON:

# If you want to use MongoDB instead of Sqlite, make this ON:
set (USE_MONGO_DB OFF)

Important

The file ./resources/mongodb_connection_string.txt must be present in that case, containing the connection string to your own MongoDB database.

The server will automatically create and populate all the necessary collections for you.

💻 Client

Within the Client directory, run the following for your operating system of choice (self-contained):

🪟 Windows

dotnet publish -c Release -r win-x64 --self-contained true /p:PublishSingleFile=true /p:IncludeNativeLibrariesForSelfExtract=true

🍎 MacOS

dotnet publish -c Release -r osx-x64 --self-contained true /p:PublishSingleFile=true

🐧 Linux

dotnet publish -c Release -r linux-x64 --self-contained true /p:PublishSingleFile=true

🏗️ Server Infrastructure

🧠 State Management

📍 States

State Name	Purpose	Description
Login	Initial state / Authentication	The client has just connected and is not yet aligned with a user
Menu	Menu	The main hub for all primary actions, such as joining a room, viewing statistics, etc.
Room Member	Waiting room	The waiting state for all room guests for when until the room admin wishes to start the game. The user may request to see the room data and the statistics of the users that are in the room. Leaving the room will notify everyone else in it.
Room Admin	Waiting room	Same as the Room Member State, but may also perform admin actions; kick players, change the room data and start the game. As an admin, leaving the room will close it & notify others.
Game	Playing the game	The actual game state. Can request questions and submit answers. Leaving it prompts the same behavior as Room Member and Room Admin (if the client is the admin of the room).
Finished Game Early	Waiting place	The player has finished answering all questions, though some players did not. Leaving behaves the same as in the Game state.

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🔁 Transitions

From	To	Trigger/Event	Description
	Login	Starting the client	The client was connected.
Login	Menu	Login / Signup	The client has been authenticated.
Menu	Login	Logout	User logged out.
Menu	Room Member	Join room	User joined a room.
Menu	Room Admin	Create room	User created a room.
Room Member	Menu	Leaving / Kicked / Admin left	User going back to the menu.
Room Admin	Menu	Closing room	User going back to the menu and closing the room.
Room Member/Admin	Game	Admin started the game	Game was started.
Game	Finished Game Early	User finished the current game	User finished the game.
Finished Game Early	Room Member/Admin	Game finished	End of game.

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🧩 Codec model

📬 Message structure (Protocol)

🧾 Request

Field	Size	Description
Message Code	1 byte	Message code identifier
Length	4 bytes	Length of the body in bytes (For the example: N bytes)
Body	N bytes	The data

🧾 Response

Field	Size	Description
Message Type	1 byte	Message type identifier (Response / Notification)
Message Code	1 byte	Message code identifier
Length	4 bytes	Length of the body in bytes (For the example: N bytes)
Body	N bytes	The data

📦 Body Content

The content of the Body field depends on the message type. It may include:

• 🧾 Strings – Textual data (e.g., usernames, passwords)
• 🆔 Identifiers – User IDs, etc.
• ❓ Questions – Trivia questions
• 🏆 Scores – Numeric performance indicators

All body content is:

• Formatted in JSON
• 🔐 Encrypted using the predetermined cryptographic scheme

🔔 Notifications System

Simply defined as a "response with no request".

They are a replacement for client-initiated polling request, prompting instead for server-initiated, pushing packets.

Examples of such packets are admins notifying clients when the game has begun, guests notifying other room guests upon their departure, etc.

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🔐 Cryptography Overview

This project uses modern cryptographic techniques to ensure secure communication between the Server and Client. Most the encryption/decryption operations are powered by the Crypto++ library and .NET System.Security.Cryptography.

Caution

The keys are static, and are therefore not fully secure.
DO NOT use this as an example for actual Cryptography matters without making these files at runtime. We did it that way because Crypto++ and System.Security.Cryptography RSA keys are not fit for each other, hence they were both made via OpenSSL.

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🔑 Current Encryption Method: RSA (Asymmetric)

• Algorithm: RSA (1024-bit keys)
• Library: Crypto++ and System.Security.Cryptography
• Usage: Used to encrypt session secrets and sensitive data.
• Key Management:
  • Server and Client each have their own RSA private key and the other public key.
  • Public/private keys are stored in .pem files.
  • Keys are loaded at startup from the files.

🛠 Other Encryption Methods

🟡 AES (Advanced Encryption Standard)

• Algorithm: AES-256 in CBC mode
• Library: Crypto++ and System.Security.Cryptography
• Use Case: Once a session is established using RSA, AES can encrypt bulk data with lower computational cost.

🟡 OTP (One-Time Pad)

• Use Case: For lightweight or critical communications requiring unbreakable encryption (if keys are truly random and never reused).
• Library: None
• Limitations: Requires secure key exchange and perfect synchronization.

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