ZKPass

ZKPass is a secure authentication system that uses Zero-Knowledge Proofs (ZKPs) to verify user identities without revealing sensitive information.

How It Works (With ZKP Magic)

Simple Example: Email & Password or userIdentity [we call it UID] (But with ZKP)

Imagine:

• Your UID = Krishna678_INSTA@ (stored on blockchain).
• Your priKey = hidden_password (derived from UID, never stored).

Login Flow:

1. You Claim:
   _"I’m Krishna678_INSTA@ and know the secret hidden_password."
2. ZKP Proof:
   • Client generates a cryptographic proof using:
     • priKey (derived from UID)
     • Proving Key (pre-setup math puzzle)
3. Verification:
   • Backend checks the proof against:
     • Your UID (from blockchain)
     • Verification Key (math "lock")
   • ✅ Valid? → Logged in! (No secrets exposed)
   • ❌ Invalid? → Rejected.

Why It's Secure:

• 🔒 Zero-Knowledge: Proof reveals nothing about priKey.
• ⚡ Fast: Verification takes 1-2ms (even on-chain).
• 🛡️ Unfakeable: Impossible to guess valid proof without priKey.

(Uses zk-SNARKs with Groth16 algorithm for optimal efficiency.)

---

Project Structure

The project is organized into several key components:

• Frontend: React application for user interface
• Backend: Express API for handling authentication requests
• Blockchain: Smart contracts for storing UIDs
• ZKP: Zero-Knowledge Proof circuits for secure authentication

Features

• Secure user registration with UID
• Recovery phrase generation for account recovery
• Zero-Knowledge Proof-based login
• UID recovery using recovery phrase
• Blockchain storage of user identifiers

Getting Started

Prerequisites

• Node.js (v16+)
• npm or yarn
• Hardhat for blockchain development

Installation

1. Clone the repository

2. Install dependencies for each component:

# Backend
cd backend
npm install

# Frontend
cd ../frontend
npm install

# Blockchain
cd ../blockchain
npm install

# ZKP
cd ../zkp
npm install

Running the Application

Backend

cd backend
npm run dev

The backend server will start on http://localhost:3001

Frontend

cd frontend
npm run dev

The frontend development server will start on http://localhost:5173

Blockchain (Local Development)

cd blockchain
npx hardhat node

In another terminal, deploy the contract:

cd blockchain
npx hardhat run scripts/deploy.ts --network localhost

Authentication Flow

Registration

1. User enters a unique identifier (UID)
2. System generates a recovery phrase linked to the UID
3. UID is stored on the blockchain
4. User saves the recovery phrase securely

Login

1. User enters their UID.
2. System derives a private key from the UID.
3. A Zero-Knowledge Proof is generated to verify the user knows the private key.
4. The proof is verified without revealing the private key.
5. If valid, the user is authenticated.

Recovery

1. User enters their recovery phrase.
2. System derives the UID from the recovery phrase

Security Considerations

• Private keys are never stored or transmitted anywhere
• Zero-Knowledge Proofs ensure secure authentication
• Recovery phrases should be stored securely by users