OpenWrt does it somewhat like described. If booted unconfigured you can ssh into it as root without any password. The web interface asks for a new one as the fi

OpenWrt does it somewhat like described. If booted unconfigured you can ssh into it as root without any password. The web interface asks for a new one as the first thing to do. I would like it if they would do the same via ssh so you immediately know someone had access before you. I think it is the best solution because it makes you immediately notice that you might not actually want anybody to login without any password at all. And any other method has worse trade offs.