I have an SSH server providing access to my files at home, secured by a private key.

I'd like to be able to synchronise those files with my Android phone (Samsung Galaxy Note, running Cyanogenmod 11 (Android 4.4.2).  I need two-way synchronisatoin: edits and deletes on the phone should be synchronised to the server, and edits on deletes on the server should be synchronised to the phone.

Ideally, this tool would run in the background, but I would be able to trigger it manually if required.

Does such a tool exist?  I've been unable to find one either in the Play Store or F-Droid.