Healthcare Blockchain System with TLS

A secure, blockchain-based patient record system built with Flask, featuring:

• ⛓️ Custom Blockchain with Proof-of-Work
• 🔐 RSA Digital Signatures for block validation
• 🛡️ TLS Encryption using self-signed certificates
• ⚒️ Parallelized Mining Simulation
• 🧮 Miner Wallets & Leaderboards
• 🔍 Blockchain Explorer

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Project Structure

blockchain/
├── app.py # Main Flask application
├── templates/ # HTML templates (UI)
│ ├── index.html
│ └── miners.html
| |__ explorer.html
├── static/ # Optional static files (CSS/JS)
├── chain.json # Stores the blockchain data
├── miners.json # Tracks miner stats and rewards
├── private_key.pem # RSA private key
├── public_key.pem # RSA public key
├── cert.pem # TLS certificate (self-signed)
└── key.pem # TLS private key

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Setup Instructions

1. Clone this repository

git clone https://github.com/89P13-24/TLS-Implementation.git
cd TLS-Implementation/blockchain

2. Create a virtual environment and install dependencies

python -m venv venv
source venv/bin/activate    # On Windows: venv\Scripts\activate
pip install -r requirements.txt

3. Generate TLS certificates (if not already present)

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365 -nodes

4. Run the application

python app.py

5. Then open your browser and navigate to:

https://localhost:5000

You may see a browser warning due to the self-signed certificate. Accept the warning to proceed locally.

Features

• Add Patient Records: Immutable medical entries tied to patient IDs.

• Search History: Query all blockchain entries by patient ID.

• RSA-Signed Blocks: Every block is cryptographically signed and verifiable.

• Mining Simulation: Parallel mining processes simulate real-world consensus.

• Reward System: Miners earn variable rewards based on block difficulty.

• Blockchain Explorer: View recent blocks, miner stats, and signatures.

• TLS Encryption: Ensures secure HTTPS communication.

• Validate Blockchain: Make sure the blockchain is valid at any time

Developer Tools

• /miners – View recent blocks, wallet balances, and miner leaderboard.

• /wallets – View current wallet balances.

• /miner_stats – View raw JSON stats for all miners.

• /get_chain – Get the full blockchain JSON.

• /explorer – Blockchain Explorer UI route.

Video link

• Watch the video demo at: https://youtu.be/d17syiU7zrk

Notes

• RSA keys and TLS certs are generated once and reused.

• Make sure multiprocessing.set_start_method("fork") is used only inside if name == "main" on macOS/Linux.

• All data is stored in local JSON files – easy to inspect and portable

Future possible improvements

• Deploy publicly using NGINX + Let’s Encrypt for real TLS

• Role-based login (e.g., doctor vs. admin)

• Blockchain Explorer search, filter, and pagination

• Encryption for patient records at rest

Team Members:

• Soumya Savarn (220150031)
• Ishan Gupta(220150034)
• Saptarshi Mukherjee(220150019)