FileCrypt

Interactive file encryption with Argon2id (key derivation) and ChaCha20-Poly1305 (authenticated encryption).

Drag a file into the terminal: the tool auto-detects encrypt/decrypt. Password input is hidden and never touches shell history.

License: GNU AGPL v3 or later — see LICENSE.

Features

• Drag & drop, no flags to remember.
• Auto mode detection via file header.
• Streaming in 8 MiB chunks, low memory on multi-GB files.
• Colored output, progress bar with percent, sizes and speed.
• CLI mode: batch files, --encrypt / --decrypt, -o, -y, -k.
• Detects wrong passwords, tampering, truncation and chunk reordering.
• Atomic output, never overwrites without asking.

Install

pip install filecrypt-argon2id
filecrypt --help

Or from source:

git clone https://github.com/msv1d/filecrypt.git
cd filecrypt
pip install -r requirements.txt
python filecrypt.py

Usage

Interactive (simplest):

python filecrypt.py

Encrypted files get .obf2id: photo.jpg -> photo.jpg.obf2id and back.

With arguments:

# auto mode, one or more files
python filecrypt.py report.pdf backup.zip

# forced modes
python filecrypt.py -e secret.docx
python filecrypt.py -d secret.docx.obf2id

# custom output, overwrite without asking, keep source
python filecrypt.py -e input.bin -o output.obf2id -y -k

python filecrypt.py --help
python filecrypt.py --version

Exit code: 0 on success, 1 if any file failed.

Format

Header stores Argon2 parameters, so they can be raised later. Untrusted headers are capped: time <= 10, memory <= 256 MiB, parallelism <= 8, chunk <= 64 MiB. See the docstring in filecrypt.py.

Security notes

• Strength depends on the password. Use a long passphrase (20+ chars).
• Wrong password fails on the first chunk; later failures mean modification.
• Deleting the original is a plain delete, not a secure wipe.
• Python cannot reliably erase secrets from memory.
• Not independently audited.

License

Copyright (C) 2026 FileCrypt contributors.

Free software under GNU Affero General Public License v3 or later. Full text in LICENSE: you may use, modify and share it; modifications stay under AGPL, and network use of a modified version requires offering the source to users.