Add SFTP support

[tobihagemann]

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Summary

Add support for SFTP.

Motivation

As far as I know, there is no way to access a vault via SFTP (e.g., using "Other File Provider"). Direct support would be required. Not to be confused with FTP(S).

Considered Alternatives

No response

Anything else?

Depends on cryptomator/cloud-access-swift#25

[IOZZYS]

I literally just started reading up on cryptomator 3 minutes ago for the exact same purpose.
However, if I understand it correctly, you're supposed to sync the cloud storage with your local directory using an external app and cryptomator makes sure everything you upload while syncing ends up encrypted and anything that gets downloaded ends up encrypted.
If I'm wrong and it works without an external sync app with other cloud storage protocols, than I agree, sftp deserves as much consideration as any other protocol, I love sftp.

[ajimix]

@tobihagemann is there any plan to work on this in the near future?

[tobihagemann]

There aren't any plans in the near future. But we're always open to open-source contributions, if there is anyone that like to see this implemented sooner than later.

[jamesgreenblue]

Is there any technical reason why supporting Cryptomator with SFTP and the iOS Files app is particularly difficult? Is it because some caching/offline support would be needed?

Adding SFTP support would open Cryptomator for Linux self-hosting, or to use with services like https://rsync.net and https://www.hetzner.com/storage/storage-box/

If there was a way to specifically sponsor a small bounty towards the development of this feature I would!