Secure File Encryption Tool (XXTEA)

A Linux-integrated, system-wide, multithreaded file encryption tool implemented in C, based on the XXTEA (Corrected Block TEA) algorithm.
This project focuses on deep integration with the Linux operating system, POSIX multithreading, and system-wide availability via the Linux execution path, rather than providing a standalone cryptographic library.

Project Focus

• Encryption and decryption of both single files and batch directories, with multithreaded processing enabled for batch operations
• Support for arbitrary file types, including text files, media files, archives, and large binary files
• System-level integration with Linux, allowing the tool to be installed system-wide and executed from any directory
• Per-file cryptographic key management, where encryption keys are automatically generated and stored as separate key files

The tool is designed to behave like a native Linux command-line utility, integrating closely with the operating system rather than functioning as a standalone or library-based encryption program.

Usage (System-Wide)

System-Wide Installation

sudo cp crypto_tool /usr/local/bin/
sudo chmod +x /usr/local/bin/crypto_tool

Verify:

which crypto_tool
crypto_tool

Encrypt a single file

crypto_tool encrypt <input_file>

Decrypt a single file

crypto_tool decrypt <encrypted_file>

Encrypted files use the _E suffix by default.

Batch mode (multithreaded)

crypto_tool <encrypt|decrypt> <directory_path> --batch

• Spawns multiple worker threads
• Processes files in parallel
• Main thread waits for collective completion

Sample

Automatically generated key file and encrypted output

Encrypting an audio file (M4A)

Encrypting an image file (PNG)

Encrypting a large ZIP archive

CPU usage comparison: single-thread vs multithreaded batch encryption