🖼️ pinlock-img v9

Authenticated PNG Image Vault

Secure • Deterministic • Authenticated Image Protection

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📌 Overview

pinlock-img is a password-based image protection tool for PNG files.

It ensures:

• No silent corruption
• Safe failure on wrong password
• Tamper detection via authentication

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🔐 Core Design

🔑 Key Derivation

• PBKDF2-HMAC-SHA256
• 200,000 iterations
• Salt: pinlock-img-v9

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🧠 Dual-Key Architecture

• XOR Seed (16 bytes) → deterministic noise stream
• Authentication Key (16 bytes) → HMAC-SHA256

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🛡️ Authenticated Encryption

Encrypt-then-MAC design:

• Encrypt data
• Generate HMAC
• Store tag in PNG metadata (pinlock_auth)

Decryption only proceeds after successful verification.

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⚙️ How It Works

Encryption

1. XOR transform applied
2. HMAC generated
3. Tag embedded in PNG
4. .lock suffix added

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Decryption

1. Extract HMAC
2. Verify integrity
3. If valid → decrypt
4. If invalid → abort safely

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🚀 Features

• 🔐 Password-based protection
• 🛡️ HMAC-SHA256 authentication
• 📂 Batch processing
• 🧪 Dry-run mode
• 💾 Atomic file writes

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📦 Installation

Requires Python 3.8+

pip install numpy Pillow

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📖 Usage

python pinlock-img.py /path/to/file_or_directory

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Dry Run

python pinlock-img.py /path/to/files

Then:

Dry Run? (y/n): y

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⚠️ Security Notes

• Strong authentication (HMAC-SHA256)
• PBKDF2 protects against brute-force

However:

• Uses deterministic XOR transformation
• Not equivalent to AES-GCM or modern AEAD

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📜 License

MIT License © 2026 Fox Hackerz

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🦊 About Fox Hackerz

We build tools focused on:

• Cybersecurity
• Automation
• Developer tools

📌 GitHub: https://github.com/foxhackerzdevs

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