🔐 SecureChat

A secure real-time messaging application developed in Java using Socket Programming, Java Swing, and a hybrid cryptographic approach combining RSA and DES for end-to-end encrypted communication.

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📖 Overview

SecureChat enables two users to exchange messages securely over a network. The application uses RSA (2048-bit) to securely exchange a DES session key, after which all chat messages are encrypted using DES/CBC/PKCS5Padding before transmission.

The project demonstrates the implementation of hybrid encryption, client-server communication, and desktop GUI development.

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✨ Features

• End-to-End Encrypted Messaging
• RSA-2048 Secure Key Exchange
• DES/CBC/PKCS5Padding Message Encryption
• Real-Time Client-Server Communication
• Java Swing GUI
• Multiple Client Support
• Socket Programming using TCP
• Encryption & Decryption Visualization
• Secure Message Transmission

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🛠 Technologies Used

• Java
• Java Swing
• Java Socket Programming
• RSA Cryptography
• DES Encryption
• Object Serialization
• Multithreading

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📂 Project Structure

SecureChat/
│
├── src/
│   └── securechat/
│       ├── Client.java
│       ├── Server.java
│       ├── Message.java
│       ├── RSAUtil.java
│       ├── DESUtil.java
│       └── EncryptionDialog.java
│
├── screenshots/
│   ├── Client.png
│   ├── Server.png
│   ├── Login.png
│   ├── Alice Keys.png
│   ├── Bob Keys.png
│   ├── Chat.png
│   │
│   ├── Encryption/
│   │   ├── Plaintext.png
│   │   ├── DES_Encryption.png
│   │   ├── RSA_Key_Wrapping.png
│   │   └── Ciphertext.png
│   │
│   └── Decryption/
│       ├── Received_Ciphertext.png
│       ├── RSA_Key_Unwrapping.png
│       └── DES_Decryption.png
│
├── README.md
└── .gitattributes

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🔐 Encryption Workflow

Sender
   │
   │ Generate DES Session Key
   ▼
Encrypt Message using DES
   │
Encrypt DES Key using Receiver's RSA Public Key
   │
Send Ciphertext + Encrypted DES Key
   │
────────────── Network ──────────────
   │
Receiver decrypts DES Key using RSA Private Key
   │
Decrypt Ciphertext using DES
   ▼
Original Message

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🚀 How to Run

1. Clone the Repository

git clone https://github.com/Ashutosh-789/SecureChat.git

2. Open the Project

Open the project in Eclipse or IntelliJ IDEA.

3. Run the Server

Run:

Server.java

4. Run Client 1

Run:

Client.java

Enter a username.

5. Run Client 2

Run:

Client.java

Enter another username.

6. Start Chatting

Send encrypted messages between clients.

Click on any message bubble to view the complete encryption and decryption process.

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📚 Learning Outcomes

• Java Socket Programming
• Client-Server Architecture
• Hybrid Encryption (RSA + DES)
• Secure Key Exchange
• Multithreading
• Java Swing GUI Development
• Secure Network Communication

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👨‍💻 Author

Ashutosh Baliarsingh

• GitHub: https://github.com/Ashutosh-789
• LinkedIn: https://linkedin.com/in/ashutosh-baliarsingh-2539432a1

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