# What options can be put into a SSH authorized_keys file?

I found this article on options that can be put before a key in the authorized_keys file. I was wondering though, are there more? Options listed in the article are

• from="domain"
• command="commandtorun"
• no-port-forwarding
• no-X11-forwarding
• no-agent-forwarding
• no-pty

Update It appears that the original article is now inaccessible. Because of that I've now changed the link to point to the archive.org version.

• The link is broken. – starfry Feb 9 '17 at 9:49
• ah, good find @starfry. I've updated the link to point to the archive.org snapshot. – mozillalives Feb 9 '17 at 15:58

All options are detailed in the sshd(8) man page; search for AUTHORIZED_KEYS FILE FORMAT.

At the moment, those options are:

• cert-authority
• command="command"
• environment="NAME=value"
• expiry-time="timespec"
• from="pattern-list"
• no-agent-forwarding
• no-port-forwarding
• no-pty
• no-user-rc
• no-X11-forwarding
• permitlisten="[host]:port"
• permitopen="host:port"
• principals="principals"
• restrict
• tunnel="n"
• ah... that's the man page I was looking for. Thanks – mozillalives May 18 '10 at 14:22

Basically, everything valid for your version is documented in sshd(8) manual page, under "AUTHORIZED_KEYS FILE FORMAT".

Check 'man sshd' on your local unix-ish box for more info. My osx box has the following:

• command="command"
• environment="NAME=value"
• from="pattern-list"
• no-agent-forwarding
• no-port-forwarding
• no-pty
• no-user-rc
• no-X11-forwarding
• permitopen="host:port"
• tunnel="n"