KEY VS Snebu

I have gone through many small projects such as a P2P "airdrop-like" file sharing between PCs, a simple filehosting service with access management (in pair with my friend), GTK GUI for Ventoy.org before there was an official one, AI-powered webcam filter for linux allowing to shift viewframe of the camera to always center on your face, an Ubuntu remix with flatpaks instead of snaps (over 100 upvotes on r/linux, lol), and a number of not very linux related open hardware projects: a raspberry PI Compute Module 4 carrier board, a tiny implementation of raspberry pi foundation's micro-controller rp2040, as well as a 80% keyboard (which turned out to be kinda bad tbh)

As such, I use tar for the serialization of backup data for Snebu (https://www.snebu.com), which has a plugin (tarcrypt) that operates on the data streams. Snebu ingests tar format, and emits tar format, so all you need to backup/restore a host is ssh access (server can pull backups, or client can push backups). So tarcrypt was added as way to do client-side encryption, but still be able to to submit recognizable tar files to Snebu's backend (which indexes, de-duplicates, and snapshots backups).

Snebu, on github. Simple Network Encrypting Backup Utility.

Details are at https://www.snebu.com/tarcrypt.html if you want to look it over (and tarcypt is part of the Snebu project https://github.com/derekp7/snebu). I'd love to get another pair of eyes on this to point out any non-obvious security limitations.

Since I've had a handful of users ask about cloud storage for Snebu, Would you be interested in adding Snebu as a supported protocol? It should be similar to how you currently support Borg. For Snebu, the client runs find and tar, sending results via ssh to the snebu binary on the remote host. And more recently client-side public key encryption support has been added via a client-side filter called "tarcrypt". Ideally, a customer would use Snebu to back up to a local device on their network (for example a Raspberry Pi with a large USB drive attached), and then use Snebu's efficient replication to send deltas to the cloud-hosted server. Client files are stored individually (deduplicated) on the Snebu server, and metadata is in an SQLite DB (advantages over Borg is more open standards for the data storage and public-key encryption, disadvantage is file-level instead of block-level deduplication and a project that isn't as widely used).

If you are interested, I would be more then happy to have an extended discussion with you going over implementation options, and updating the client side script to make it work better with your service. (https://www.snebu.com, https://github.com/derekp7/snebu, and the tarcrypt extensions to tar are described at https://www.snebu.com/tarcrypt.html).

Would a mention of my open source backup system, Snebu (or https://github.com/derekp7/snebu) fit in this thread? Elevator pitch -- GPLv3 C code, snapshot-based, compresses, encrypts, deduplicates, can back up clients without installing an agent (just need ssh, bash, tar, and find commands on client for "pull" backups), push backups can have restricted permissions (i.e., give a client permission to push backups only, but not delete backups, or give a user restore-only permissions). Uses tar to collect the data, stores metadata in an SQLite DB on the server, files are stored in LZO format (can be read directly with lzop) (unless client-side encryption is used, but the data can still be decrypted with openssl then decompressed with lzop). Encryption is public-key based instead of needing to keep a shared symmetric key or passphrase laying around on your backup server.

I created and use Snebu -- I'm working on getting it submitted to Fedora (waiting on package review now), doing daily snapshots of my fleet to a raspberry pi with external 12 TB WD Easystore drive. Provides push or pull based backups, granular access permissions, client-side public key encryption (RSA + AES-256) with HMAC validation, server-based data catalog housed in SQLite, multiple client support, global (cross client) file-level deduplication and compression. Works great for backing up a large range of OS versions since the client-side doesn't need an agent -- just bash, tar, find, and ssh.

snebu (c) - https://github.com/derekp7/snebu