CryptiHub - Secure End-to-End Encrypted Chat System

A secure chat application featuring room-based end-to-end encryption, designed to protect your communications from eavesdropping.

Key Features:

• 🔒 End-to-End Encryption using Fernet (AES-256)
• 🛡️ Room-Based Authentication with unique keys
• 🌐 Real-Time Broadcasting to multiple clients
• 🧵 Thread-Safe socket handling
• 🔑 PBKDF2 Key Derivation (1.2M iterations)

Installation:

git clone https://github.com/pevinkumar10/CryptiHub.git
cd CryptiHub

Install dependencies:

• In windows

     pip3 install -r requirements.txt

• In Linux

     apt-get install python3-tk

Configuring CryptiHub:

• Configuring Server:
  • This is the default HOST and PORT configuration. If you need to change it , then modify it server/modules/core.py

    HOST = ''
    PORT = 1234
    

• Configuring Client:
  • This is the default HOST and PORT configuration. If you need to change it , then modify it client/client.py

    HOST = ''
    PORT = 1234
    

Usage:

Starting the Server:

python3 server/server.py

Connecting Clients:

python3 clients/client.py

Security Architecture:

1. Key Derivation
   Uses PBKDF2-HMAC-SHA256 with:

   • 1,200,000 iterations
   • 16-byte random salt per message
   • 32-byte derived keys

2. Encryption

   • AES-256 in GCM mode via Fernet
   • Message-level salts prevent replay attacks

3. Authentication

   • Clients must prove room ID to enter the chat
   • Username collision prevention

Limitations:

⚠️ Note: This implementation uses symmetric encryption with a shared room key. For true E2EE where the server cannot decrypt messages, consider:

1. Implementing Diffie-Hellman key exchange
2. Adding ephemeral session keys
3. Client-side key storage

License:

MIT © 2025 PevinKumar A