CryptoTool - Comprehensive Cryptography Suite

A full-featured cryptography tool with web frontend built using MERN Stack and MVC architecture.

Features

Substitution Ciphers

• Caesar Cipher / ROT13: Simple shift cipher
• Vigenère Cipher: Polyalphabetic substitution cipher
• Monoalphabetic Substitution: Custom alphabet mapping
• Playfair Cipher: Digraph substitution cipher

Transposition Ciphers

• Rail Fence Cipher: Zigzag pattern encryption
• Double Columnar Transposition: Grid-based transposition

Advanced Encryption

• DES (Data Encryption Standard): Symmetric-key algorithm
• RSA: Asymmetric encryption
• Diffie-Hellman: Key exchange protocol

Project Structure

cryptool/
├── backend/
│   ├── models/              # Cipher algorithm implementations
│   │   ├── substitution/    # Caesar, Vigenère, Playfair, etc.
│   │   ├── transposition/   # Rail Fence, Columnar
│   │   └── advanced/        # DES, RSA, Diffie-Hellman
│   ├── controllers/         # Business logic & request handlers
│   ├── routes/              # API endpoints
│   ├── config/              # Configuration files
│   ├── server.js            # Express server
│   └── package.json
└── frontend/
    ├── src/
    │   ├── components/      # React components
    │   ├── services/        # API service layer
    │   ├── pages/           # Page components
    │   ├── App.js
    │   └── index.js
    ├── public/
    └── package.json

Installation

Backend

cd backend
npm install
npm start

Frontend

cd frontend
npm install
npm start

Usage

1. Start the backend server (runs on http://localhost:5000)
2. Start the frontend development server (runs on http://localhost:3000)
3. Open your browser to http://localhost:3000

Technologies

• MongoDB: Database (optional for storing encryption history)
• Express.js: Backend framework
• React: Frontend framework
• Node.js: Runtime environment
• Architecture: MVC Pattern