I'd like to be able to use a ssh key for authentication, but still restrict the commands that can be executed over the ssh tunnel.
With Subversion, I've achieved this by using a .ssh/authorized_keys file like:
command="/usr/local/bin/svnserve -t --tunnel-user matt -r /path/to/repository",no-port-forwarding,no-agent-forwarding,no-X11-forwarding,no-pty ssh-rsa AAAAB3NzaC1yc2EAAAABIetc...
I've tried this with "/usr/bin/git-shell" in the command, but I just get the funky old
fatal: What do you think I am? A shell? error message.