Encrypted In-Memory File System

An in-memory encrypted file system built with FUSE (Filesystem in Userspace). All file contents are encrypted using AES-256 and stored only in memory. This makes it suitable for educational use, testing, or handling short-term sensitive data.

Key Features

• Basic file system operations: create, read, write, delete, truncate
• AES-256 encryption with CFB mode
• Per-file 256-bit encryption keys
• Purely in-memory (no disk storage)

System Requirements

• OS: Linux with FUSE support
• Python: 3.8 or later

Installation

Linux Packages

sudo apt-get install fuse libfuse-dev

Python Dependencies

pip install fusepy cryptography

Usage

Mount the file system

mkdir /tmp/memfs
sudo python fuse_in_memory.py /tmp/memfs

Basic example (in Python)

from fuse_in_memory import InMemoryFileSystem

fs = InMemoryFileSystem()
fs.create('/secret.txt', 0o644)
fs.set_key('/secret.txt', b'12345678901234567890123456789012')  # 32-byte key
fs.write('/secret.txt', b'hello world', 0, None)
print(fs.read('/secret.txt', 11, 0, None))  # Output: b'hello world'

Testing and Benchmark

Functional Demo (manual)

To manually test functionality, view printed output, and run a built-in benchmark:

python tests/demo_fuse_in_memory.py <mount_filepath>

This script uses print() to demonstrate encryption, key validation, directory handling, etc.

Unit Tests with Coverage

To run automated unit tests and measure coverage:

pytest --cov=fuse_in_memory --cov-report=term-missing tests/test_fuse_in_memory.py

This will:

• Execute all Pytest-based unit tests
• Report code coverage and highlight untested lines

Notes

• Each file must have its own 32-byte (256-bit) encryption key
• Read/write operations are blocked without a key
• Data is volatile and lost when the program exits