Diffie-Hellman Key Exchange Startup Documentation

Introduction

Welcome to the startup documentation for the Diffie-Hellman Key Exchange implementation in Python. This document provides step-by-step instructions to set up and run the provided code for securely exchanging cryptographic keys over a public channel using the Diffie-Hellman protocol.

Prerequisites

Before proceeding, ensure that you have the following prerequisites installed:

• Python 3.x
• Required Python libraries: socket, tkinter

Installation

1. Clone the Repository: Clone the repository containing the Diffie-Hellman Key Exchange implementation to your local machine.

2. Navigate to the Directory: Open your terminal or command prompt and navigate to the directory where you have cloned the repository.

Setup

Server Setup

1. Navigate to Server Directory: Navigate to the Sockets directory within the cloned repository.

2. Start the Server: Execute the Server.py script by running the following command:

python3 Server.py

This command will start the server, which will listen for incoming client connections on a specified port.

Client Setup

1. Navigate to Client Directory: Navigate to the Sockets directory within the cloned repository.

2. Start a Client Instance: Execute the Client.py script by running the following command:

python3 Client.py

This command will start a client instance and initiate the Diffie-Hellman key exchange with the server.

You need 2 clients to start the key exchange.

3. Input Secret Key: When prompted, input a secret key. This key will be used in the Diffie-Hellman key exchange process.

4. Initiate Key Exchange: The client will initiate the key exchange process with the server, establishing a shared secret key securely.

Usage

1. Communication: Once the key exchange is complete, the client and server can communicate securely using the shared secret key.

2. Additional Functionality: The client script also includes a graphical user interface (GUI) built using tkinter. You can interact with the GUI to input the secret key and display received messages.

Conclusion

Congratulations! You have successfully set up and initiated the Diffie-Hellman Key Exchange implementation. You can now securely exchange cryptographic keys over a public channel using the provided Python code.

Technical Documentation for Diffie-Hellman Key Exchange Implementation

Overview

The provided code implements the Diffie-Hellman key exchange protocol using Python. Diffie-Hellman is a method for securely exchanging cryptographic keys over a public channel. This documentation aims to provide insights into the implementation, including key components, functionality, and usage instructions.

Components

1. DiffieHellman.py

• DH Class:
  • __init__(self): Initializes the Diffie-Hellman parameters (p and g).
  • calcPublicSecret(self, secret): Calculates the public key based on the private secret input.
  • calcSharedSecret(self, privSecret, publicSecret): Computes the shared secret key between two parties using their private and received public keys.

2. Client.py

• ClientSocket Class:
  • __init__(self, port): Initializes a client socket and Diffie-Hellman instance.
  • receive(self): Receives messages from the server.
  • create_header(self, message): Creates a header for sending messages.
  • send(self, message): Sends messages to the server.
  • initDiffieHellman(self): Initiates the Diffie-Hellman key exchange process.
  • start_client(self): Starts the client and initiates the Diffie-Hellman key exchange.

3. Server.py

• Server Class:
  • __init__(self, port): Initializes the server with a specified port.
  • receive(self, client): Receives messages from clients.
  • create_header(self, message): Creates a header for sending messages.
  • write(self, message, client): Writes messages back to clients.
  • initDiffieHellman(self, client): Initiates the Diffie-Hellman key exchange process for a client.
  • handle_client(self, client): Handles client connections and initiates Diffie-Hellman key exchange.
  • run_server(self): Starts the server and listens for client connections.

Usage Instructions

1. Server Setup:

   • Execute Server.py to start the server. It will listen for incoming client connections on the specified port.

2. Client Setup:

   • Execute Client.py to start a client instance.
   • Input a secret key when prompted. This key will be used in the Diffie-Hellman key exchange.
   • The client will initiate the key exchange with the server.

3. Key Exchange:

   • The Diffie-Hellman key exchange will be performed between the client and server, allowing them to establish a shared secret key securely.

4. Communication:

   • Once the key exchange is complete, the client and server can communicate securely using the shared secret key.

Additional Notes

• Security: While Diffie-Hellman provides a secure method for key exchange, it's crucial to implement additional security measures for data transmission, such as encryption.
• Error Handling: The code provides basic error handling for message transmission; however, further enhancements can be made to improve robustness.
• Dependencies: The code utilizes the socket library for network communication and tkinter for the client's graphical user interface. Ensure these libraries are installed to run the code successfully.

Conclusion

This technical documentation provides an overview of the Diffie-Hellman key exchange implementation, including its components, functionality, and usage instructions. By following the provided guidelines, users can securely exchange cryptographic keys over a public channel using the provided Python code.