These instructions will work on any FreeBSD install, but you don't necessarily need nano to accomplish it. On a jail on FreeNAS you need nano because the keyboard combinations required to edit the config files cannot be executed on the web gui console.

Make sure root password is set:

passwd

Update pkg database:

pkg update

Install nano text editor:

pkg install nano

Open ssh daemon config file with nano:

nano /etc/ssh/sshd_config

You can ctrl + shift + w to find text

Un-hash and edit the following values:

• PermitRootLogin yes
• PasswordAuthentication yes

ctrl + shift + x to exit nano

Press Y to save changes

Press Enter to confirm write

Enable the SSH daemon:

sysrc sshd_enable=yes

Start SSH daemon:

service sshd start