hat.sh
Hat.sh is a web app that provides secure file encryption in the browser. It's fast, secure and runs locally, the app never uploads the files to the server. It uses modern secure cryptographic algorithms with chunked AEAD stream encryption/decryption.
V2 of hat.sh introduced memory efficient in-browser large file chunked encryption using streams with libsodium.js
Usage
Features
Security
- XChaCha20-Poly1305 - for symmetric encryption.
- Argon2id - for password-based key derivation.
- X25519 - for key exchange.
The libsodium library is used for all cryptographic algorithms.
Privacy
- The app runs locally in your browser.
- No data is ever collected or sent to anyone.
Functionality
- Secure encryption/decryption of files with passwords or keys.
- Secure random password generation.
- Asymmetric key pair generation.
- Authenticated key exchange.
- Password strength estimation.
Offline Use
The app can be easily self hosted, please follow the installation instructions.
What's new in v2
- switching to xchacha20poly1305 for symmetric stream encryption and Argon2id for password-based key derivation. instead of AES-256-GCM and PBKDF2.
- using the libsodium library for all cryptography instead of the WebCryptoApi.
- in this version, the app doesn't read the whole file in memory. instead, it's sliced into 64MB chunks that are processed one by one.
- since we are not using any server-side processing, the app registers a fake download URL (/file) that is going to be handled by the service-worker fetch api.
- if all validations are passed, a new stream is initialized. then, file chunks are transferred from the main app to the service-worker file via messages.
- each chunk is encrypted/decrypted on it's on and added to the stream.
- after each chunk is written on disk it is going to be immediately garbage collected by the browser, this leads to never having more than a few chunks in the memory at the same time.
Browser Compatibility
We officially support the last two versions of every major browser. Specifically, we test on the following
- Chrome on Windows, macOS, and Linux , Android
- Firefox on Windows, macOS, and Linux
- Safari on iOS and macOS
- Edge on Windows
Safari and Mobile browsers are limited to 1GB files, due to lack of support with server-worker fetch api.
Official running instances of the app
| # | URL |
|---|---|
| 1 | hat.sh |
| 2 | hat.now.sh |
| 2 | hat.vercel.app |
Donations
The project is maintained in my free time. Donations of any size are appreciated :
Bitcoin: bc1qh0lmuj34h2z4kr7j2sx8fegqvvaj35ycdtglw2
Monero: 84zQq4Xt7sq8cmGryuvWsXFMDvBvHjWjnMQXZWQQRXjB1TgoZWS9zBdNcYL7CRbQBqcDdxr4RtcvCgApmQcU6SemVXd7RuG
Kofi: buy me a coffee
Open Collective : https://opencollective.com/hatsh