🛡️ Secure Document Registry & Verification System

A decentralized-style document integrity system built with the MERN Stack. This application allows users to register documents, generate unique cryptographic fingerprints (SHA-256 hashes), and verify the authenticity of files to detect tampering.

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🏗️ Architecture

The system follows a Client–Server Architecture with a focus on Security at the Edge (Frontend Hashing).

1️⃣ Frontend – Next.js 16

• Local Hashing: Uses crypto-js to generate a SHA-256 hash before the file leaves the user's device.
• State Management: Implemented with React Context API for global authentication and session handling.
• UI & Animation: Built using Tailwind CSS and Framer Motion.

2️⃣ Backend – Node.js & Express

• Integrity Re-Verification: The backend re-hashes uploaded files using the Node.js crypto module to ensure the file was not modified during transmission.
• File Handling: Managed with Multer for local or cloud storage.
• Database Storage: File metadata and hashes are stored in MongoDB.

3️⃣ Communication

• REST APIs are used for communication between frontend and backend.
• JWT Authentication secures all protected endpoints.

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🔒 Security Decisions

To meet the high-security requirements of a document registry, the following measures were implemented:

SHA-256 Hashing

Each document receives a unique cryptographic fingerprint. Even a single-bit modification changes the entire hash.

Double-Layer Verification

Hashing occurs at two levels:

• Frontend: Ensures transparency for users.
• Backend: Ensures system-level verification and prevents tampering.

HttpOnly Cookies

JWT tokens are stored in HttpOnly & Secure cookies to protect against XSS (Cross-Site Scripting) attacks.

Protected Routes

Private pages such as the Dashboard and Admin Panel are protected using a Higher-Order Component (HOC) that verifies authentication before access.

CORS Policy

API requests are restricted to trusted origins to prevent unauthorized third-party access.

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🚀 Installation

Follow these steps to run the project locally.

1️⃣ Prerequisites

• Node.js v18 or higher
• MongoDB Atlas account or Local MongoDB instance

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2️⃣ Backend Setup

cd backend
npm install
npm start

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3️⃣ Frontend Setup

cd frontend
npm install
npm run dev

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🔑 Environment Variables

Create a .env file in the backend directory and add the following variables:

# Server Configuration
PORT=2000

# Database
MONGO_URL=your_mongodb_connection_string

# Authentication
JWT_SECRET=your_super_secret_key_123

# File Uploads
MAX_FILE_SIZE=5242880

Note: Use a long and complex JWT_SECRET in production environments for better security.

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📁 Project Structure

project-root │

├── backend

│ ├── controllers

│ ├── models

│ ├── routes

│ ├── middleware

│ ├── uploads

│ └── server.js

│

├── frontend

│ ├── components

│ ├── context

│ ├── pages

│ └── utils

│

└── README.md

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🛠️ Tech Stack

Layer	Technology
Frontend	Next.js, Tailwind CSS, Framer Motion
Backend	Node.js, Express.js
Database	MongoDB
Security	SHA-256 Hashing, JWT, HttpOnly Cookies
File Handling	Multer
Icons	Lucide React

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📌 Features

• Secure document registration
• SHA-256 cryptographic fingerprint generation
• File authenticity verification
• Double-layer integrity validation
• JWT-based authentication
• Secure cookie storage
• Protected dashboard and admin routes
• MongoDB document metadata storage
• File upload and verification workflow

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🔄 System Workflow

1. User uploads a document from the frontend.
2. The frontend generates a SHA-256 hash using crypto-js.
3. The file and hash are sent to the backend API.
4. The backend re-calculates the hash using the Node.js crypto module.
5. If hashes match, the document metadata and hash are stored in MongoDB.
6. Later, users can upload the same document again to verify authenticity.

🎥 Demo

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👨‍💻 Developer

Asim Mir Full-Stack Web Developer with cyber-security.