PdfFinalBoss 🛡️ (100% Free & Private PDF Lock, Unlock & Vault Utility)

PdfFinalBoss is a premium, cinematic web utility designed to unlock password-protected PDFs or encrypt documents with AES-256 secure locks. Built with zero ads, zero watermarks, no account requirements, and enterprise-grade privacy engineering.

🌐 Live Application: https://pdf-final-boss.vercel.app
💻 GitHub Repository: https://github.com/ashishgit4/PdfFinalBoss
☕ Support & Ko-fi: https://ko-fi.com/ashishsharma11

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🌟 Key Features

1. 🔓 Bypass & Apply Restrictions

• Unlock PDF: Instantly remove owner-restricted credentials or open-passwords on PDF files up to 100 MB. Automatically detects restricted PDFs and decrypts them in seconds.
• Lock PDF: Encrypt documents with AES-256 military-grade standard encryption. Includes a live Password Strength Indicator and a 16-character Random Password Generator.

2. 🔑 Zero-Knowledge Local Password Vault (Auto-Unlock)

• When locking a PDF, check the "Remember this password in my vault" option.
• Passwords are encrypted and saved client-side only inside your browser's local storage (localStorage), mapped to the document's unique SHA-256 PDF hash.
• When you upload the exact same PDF again, the system recognizes the hash and prompts an Auto-Unlock action. Your passwords never leave your device or get sent to any server.

3. ⏳ 24-Hour Auto-Wipe Policy

• All uploaded documents and processed output files are automatically and permanently purged from server disks 24 hours after upload by a background cleanup worker.
• Uploaded files are verified via binary magic bytes (%PDF-) to prevent non-document payload execution.

4. 🛡️ Hardened Security & Rate Limiting

• qpdf CLI Argument Sanitization: Hardened command execution using -- argument delimiters to prevent argument injection attacks.
• Header Injection Prevention: All output filenames in Content-Disposition headers are sanitized to block HTTP Response Splitting.
• Rate Limiting: Guarded with express-rate-limit (100 API requests / 30 file uploads per 15-minute window per IP) and helmet security headers.

5. 🌓 Cinematic Day/Night Theme Engine

• Smooth transition between a starry dark cinema interface and a warm light off-white layout with dynamic background video scrims.

6. 💳 Integrated Dual Payment Hub

• International support via Ko-fi (PayPal, Apple Pay, Card).
• Domestic India support via UPI QR Code and Razorpay SDK integration.

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📂 Repository Architecture

unlockpdf/
├── backend/
│   ├── bin/                    # qpdf 12.3.2 C++ PDF binary engine
│   ├── cryptoHelper.js          # AES-256-GCM, SHA-256 & PBKDF2 cryptographic helpers
│   ├── cryptoHelper.test.js     # Automated unit test suite
│   ├── server.js                # Express API server with security & rate limiters
│   ├── package.json
│   └── .env.example             # Backend environment template
├── frontend/
│   ├── src/
│   │   ├── components/          # UI Components & ErrorBoundary
│   │   ├── pages/               # Home & BuyMeCoffeePage
│   │   ├── services/            # API Service layer
│   │   └── lib/                 # Payment SDK script loader
│   ├── index.html               # OpenGraph & SEO metadata
│   ├── package.json
│   └── .env.example             # Frontend environment template
├── package.json                 # Monorepo root scripts
├── vercel.json                  # SPA rewrite configuration
└── README.md

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🛠️ Technology Stack

• Frontend: React 19, Vite 8, TypeScript, Framer Motion, Tailwind CSS v4, Lucide React, Sonner Toasts.
• Backend: Node.js, Express, qpdf (Native C++ PDF Processing Engine), Multer, Helmet, Express-Rate-Limit, Razorpay SDK.
• Security & Crypto: Node.js Native Crypto (aes-256-gcm, sha256, pbkdf2), Binary Magic-Byte Verification.
• Testing: Node Test Runner (node --test).

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🚀 Step-by-Step Local Setup Guide

1. Prerequisites

Make sure you have Node.js (v18 or higher) installed on your machine.

2. Monorepo Installation

From the root directory of the project, install dependencies for both frontend and backend:

npm run install:all

3. Environment Setup

Copy the environment template files in both directories:

# Backend .env
cp backend/.env.example backend/.env

# Frontend .env
cp frontend/.env.example frontend/.env

4. Run Development Servers

Start the backend Express server and frontend Vite development server:

• Terminal 1 (Backend - Port 3000):

  npm run start:backend

• Terminal 2 (Frontend - Port 5173):

  npm run dev:frontend

Open your browser and navigate to http://localhost:5173.

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🧪 Running Automated Unit Tests

Run the backend cryptographic and hashing test suite:

npm test --prefix backend

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⚙️ Environment Variables Reference

Backend (/backend/.env)

Variable	Required	Default	Description
PORT	Optional	3000	Port for the Express server.
RAZORPAY_KEY_ID	Optional	rzp_test_placeholder	Public key ID for Razorpay payments.
RAZORPAY_KEY_SECRET	Optional	placeholder_secret	Secret key for verifying Razorpay HMAC signatures.
VAULT_SECRET	Optional	Default 32-char key	Secret key for AES-256-GCM vault encryption.

Frontend (/frontend/.env)

Variable	Required	Default	Description
VITE_API_URL	Optional	http://localhost:3000	Backend API URL (fallback: Render URL).

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🔒 Security & Privacy Blueprint

1. In-Memory Password Processing: Passwords submitted to the backend reside in volatile RAM only during qpdf execution and are never written to disk, logged, or recorded.
2. Zero Server Retention Vault: Local Password Vault items are encrypted client-side in browser localStorage and never transmitted over the network.
3. 24-Hour File Purge Policy: Server disk cache is automatically purged by a 24-hour cleanup worker.
4. CLI & Header Injection Protection: qpdf commands use native array arguments with -- delimiters, and download headers use sanitized filenames.

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📄 License & Credits

This project is licensed under the GPL-3.0 License.

Developed with ❤️ by Ashish Sharma.
Support open-source development on Ko-fi!