I'd like to prevent users from deleting files they have uploaded to my sftp server. I know I could set up a solution of my own using inotify/dnotify (or pam hook) and lsof which triggers a script to do something such as
chattr +i $filename after a file is uploaded and closed. But I wonder if there is something already available as a feature or a solution already vetted and available of which I'm not aware.
The current setup is that I'm using openssh sftp and users are jailed upon connecting.