PaperEncrypt: Encrypt and Decrypt Files with QR Codes

PaperEncrypt is a Python tool for encrypting and decrypting files using AES encryption and QR codes. The encrypted data can be exported in multiple formats, including PDF, image (PNG), and text. Decryption supports reading QR codes directly from these formats, making it versatile for secure data sharing.

Features

• Encrypt files: Supports AES encryption with user-provided passwords.
• Generate QR codes: Encrypted content is embedded into QR codes.
• Multiple export formats: PDF, image, and plain text.
• Decrypt files: Extract encrypted data from QR codes and restore the original content.
• All-in-memory processing: Uses in-memory buffers for improved performance.

PaperCrypt: Secure Offline Analog Storage Tool

Overview

PaperCrypt is a tool designed to securely store data offline in an analog format. It encrypts a text file and provides options to export the encrypted data as a PDF, image, or plain text. When exporting to PDF or image formats, a QR code containing the encrypted data is generated, making it easy to print and store. The data is encrypted using AES encryption and is protected by a password. Note: The password is unrecoverable, so it must be stored securely.

The primary purpose of PaperCrypt is to enable secure, analog storage of small pieces of sensitive data, such as passwords or cryptocurrency wallet public and private keys.

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Steps for Secure Storage

1. Write your data in a .txt file.
2. Encrypt the data using PaperCrypt. (Do not lose the password as it cannot be recovered.)
3. Print at least two copies of the generated QR code and store them securely in geographically separated locations.
4. Delete the .txt file and any encrypted files from your computer. (Remember to clear your trash bin.)
5. Done! Your credentials are now securely stored offline.

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Steps to Decrypt Data

1. Take a photo or scan the generated QR code.
2. Use PaperCrypt to decrypt the data using the saved QR code and your password.

Disclaimer: Ensure you follow the recommended steps for secure storage and do not lose the password. Failure to do so may result in permanent loss of access to your encrypted data.

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Prerequisites

Python Version

Ensure you have Python 3.7 or later installed.

Required Libraries

Install the following Python libraries:

• fpdf
• qrcode
• pycryptodome
• cv2 (OpenCV)
• pdf2image
• numpy

You can install all dependencies using:

pip install -r requirements.txt

Additional Requirements

For pdf2image, you must install poppler. Instructions vary by operating system:

• Ubuntu: sudo apt-get install poppler-utils
• MacOS: brew install poppler
• Windows: Download the precompiled binaries from Poppler for Windows and add the bin directory to your PATH.

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Usage

Command Line Interface

The tool provides a CLI interface for encryption and decryption.

python main.py --encrypt --file_path <file_path> [--export pdf,img,txt] [--title <title>]
python main.py --decrypt --file_path <file_path>

Parameters:

• --encrypt: Encrypt the file.
• --decrypt: Decrypt the file.
• --export: Specify export formats (comma-separated): pdf, img, txt (default: pdf).
• --output_path: (Optional) Path to save the output files.
• --title: (Optional) Title to add to the PDF.
• file_path: Path to the file to encrypt or decrypt.

Example Commands

Encrypt a file to PDF and PNG

python main.py --encrypt --file_path /path/to/file.txt --export pdf,img --title "My Encrypted File"

Encrypt a pattern of files

python main.py --encrypt --title "My Encrypted File" "/path/to/*.txt"

Decrypt a QR code from a PDF

python main.py --decrypt --file_path /path/to/encrypted_file_encrypted.pdf

Decrypt a pattern of files

python main.py --decrypt --output_path=decrypt "/path/to/*.pdf"

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Programmatic Usage

The tool provides encrypt_file and decrypt_qr functions for integration into your own projects.

Encrypt a File

from paper_encrypt.main import encrypt_file

file_path = "test_file.txt"
password = "securepassword"
encrypt_file(file_path, password, title="Secure Data", export_formats=['pdf', 'img'])

Decrypt a File

from paper_encrypt.main import decrypt_qr

encrypted_file_path = "test_file_encrypted.pdf"
password = "securepassword"
decrypt_qr(encrypted_file_path, password)

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Testing

The project includes unit tests to verify its functionality. Run the tests with:

python -m unittest discover

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Security Notes

• Use strong passwords to ensure the safety of your encrypted data.
• Keep your password safe; decryption is impossible without it.

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License

This project is licensed under the MIT License. See the LICENSE file for details.

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Contact

For issues or feature requests, please contact the developer or submit an issue on the project repository.