README.md – Final Version

secure-chat-aes-java

Console-based encrypted chat (Server & Client) using AES in Java.
A simple socket + symmetric cryptography demo, ready to evolve into a multi-user chat.

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🚀 Quick Start

Requirements

• Java 17 (recommended)
• No JavaFX required

Run with Eclipse

1. Run secure_chat_app.Server.
2. Run secure_chat_app.Client in another console.
3. Enter your name and type messages to see them encrypted & decrypted in real time.

Run with CLI

# compile all .java files
javac -d out src/secure_chat_app/*.java

# run server
java -cp out secure_chat_app.Server

# run client (in another terminal)
java -cp out secure_chat_app.Client

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🧠 How it Works

• Transport: Java TCP sockets
• Encryption: AES symmetric key (demo only)
• Flow: Client ↔ Server, messages are encrypted and decrypted at both ends

⚠️ Security note: The AES key is hardcoded for demonstration only.
In a real-world application, use environment variables, configuration files, or secure key negotiation (e.g., ECDH), and switch to AES-GCM mode.

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🗂️ Project Structure

src/
  secure_chat_app/
    AESUtil.java
    Server.java
    Client.java
    ClientHandler.java
README.md
LICENSE
.gitignore

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🧪 Sample Session

Server started. Listening on Port 12345
...
Client> Enter your name:
Marnie
You can start typing messages now:
Base64 Encrypted String: ...
Marnie: Ma bucur ca merge

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🛣️ Roadmap

• Protocol: LOGIN, LIST, MSG, WHISPER, QUIT
• Server broadcast and user registry
• AES-GCM encryption with random IV per message
• Authentication (SQLite/MySQL + bcrypt)
• JavaFX GUI
• Packaging (Maven/Gradle) + runnable JAR

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📜 License

MIT License