Crypter

Read this in other languages: Русский

A command-line tool for hashing and encrypting files, and for packing programs into a self-launching executable. A single Python script with no extra dependencies beyond cryptography.

Features

• Hash a file with several algorithms in a single pass.
• Encrypt/decrypt a file with a password (AEAD, streaming — file size is not limited by memory).
• pack — wrap any program into a self-launching .py launcher.
• --standalone — build a self-contained executable (no Python needed on the target machine).
• --sign — sign the built .exe with your certificate (Windows).
• bundle — combine several programs into one file; all run openly.
• Interactive menu when run without arguments.

Installation

python -m venv .venv
source .venv/bin/activate            # Windows: .venv\Scripts\activate
pip install -r requirements.txt      # cryptography; pyinstaller — for --standalone

Requires Python 3.10+.

Usage

Hashing

python crypter.py hash file.txt                      # sha256 by default
python crypter.py hash file.txt -a sha256 -a md5     # several algorithms
python crypter.py hash file.txt --all                # all at once

Available hashes: md5, sha1, sha256, sha512, sha3_256, sha3_512, blake2b, blake2s (md5/sha1 — checksum only).

Password encryption

python crypter.py encrypt file.txt                   # -> file.txt.enc (AES-256-GCM)
python crypter.py encrypt file.txt -a chacha20       # ChaCha20-Poly1305
python crypter.py decrypt file.txt.enc               # -> file.txt

The key is derived from the password via scrypt. The algorithm is stored in the header, so you don't specify it when decrypting. Corruption or a wrong password is detected (authenticated encryption). The password can be passed via the CRYPTER_PASSWORD environment variable.

Packing into a self-launching launcher

python crypter.py pack myprog.py                     # -> myprog_packed.py (needs Python)
python crypter.py pack myprog.py --standalone        # -> myprog_app (no Python needed)
python crypter.py pack program.exe -i none           # any binary, run directly
python crypter.py pack app.js -i node                # custom interpreter

On start the launcher decrypts the program, runs it, passes command-line arguments through, and returns its exit code. A Python program runs in-process (no temp file); anything else runs via a temporary file that is deleted after exit.

Combining programs (bundle)

python crypter.py bundle prog1.py prog2.exe          # one after another
python crypter.py bundle prog1.py prog2.exe -p       # all at once
python crypter.py bundle prog1.py prog2.py --standalone

All programs run openly, their output is visible. The resulting exit code is the highest of the codes (non-zero if any program failed).

Signing the .exe (Windows)

python crypter.py pack myprog.py --standalone --sign mycert.pfx --sign-password PASSWORD

Requires your .pfx certificate and signtool (from the Windows SDK). You obtain the certificate yourself: buy one from a certificate authority for public distribution, or make a self-signed one for your own machines. Signing confirms the author and removes SmartScreen/antivirus warnings — it is unrelated to encrypting the contents.

Building a Windows .exe

PyInstaller builds the file for the OS it runs on — there is no cross-compilation. To get a Windows .exe, run --standalone on Windows (Python + pyinstaller are only needed on the build machine, not on the target).

Important: level of protection

• encrypt/decrypt — real encryption: without the password the data cannot be read.
• pack/bundle without a password — this is obfuscation, not strong protection: the key is embedded in the launcher and a skilled person can extract it. It protects against an ordinary user, but not against a reverse engineer.

License

MIT