I'm setting up a site that will have multiple development instances running on the same server. Essentially, we'd have dev-a.whatever.com, dev-b.whatever.com, etc.. all running off a single server.

I want to give each user some bit of SSH access in order to update and check in code from our Git repository and to manage files via SFTP. However, I want to restrict each user to their own site as well. So if you have access to dev-a.whatever.com, you don't also have access to dev-b.whatever.com and so on. The restriction is already in place if I login via FTP as a certain user, I can't navigate outside my own site -- but if I grant SSH access to that account I can immediately navigate to any file on the server in SFTP.

Is RSSH part of the solution? And how can I assign the correct SSH pub key to the corresponding user? We're using BeanStalk for our Git repository management if that makes any impact.