Notes from setting up a programming/template jail

I wanted to set up a programming jail for myself and I took some notes and I thought I’d share. This will also make a good “template jail”. Feel free to send all compliments to @John and complaints to @winnielinnie (who does not actually have anything to do with this post, I just thought it would be fun to toss someone under the bus–I’m going for my “bus-driver badge” on this wacky forum).

These notes are not anything overly complicated or profound–or even that good–but I thought I’d share nonetheless in case someone is in need of a decent starting point.

I have my own ZSH and VIM configs I upload but if you have a different
shell or editor you like to use…

  • git-tiny
  • doas
    >> See sample conf and/or man page.
  • zsh
  • neovim / vim / vim-tiny
  • openssh
  • perl5
    (optional) * unison
    (optional) * rsync

== TODO ==

  • Create user
    pw user add -n john -d /home/john -G wheel -m -s /usr/local/bin/zsh
    • Give password
      passwd john


  • Edit the sshd_config. /usr/local/etc/ssh/sshd_config
            Port <NOT 22>
            AuthenticationMethods publickey
            StrictModes yes
            PubkeyAuthentication yes
            # The default is to check both .ssh/authorized_keys and .ssh/authorized_keys2
            AuthorizedKeysFile .ssh/authorized_keys .ssh/authorized_keys2
            # Only allow whitelisted users
            AllowUsers john
  • Enable OpenSSH. /etc/rc.conf
  • Start the new SSH server:
    service openssh start
  • Allow user john passwordless login.
    * Client side public key generation (if needed)
    ssh-keygen -t ed25519
    * Client side key upload (to jail).
    ssh-copy-id -i ~/.ssh/ <JAIL NAME>
    * Client side SSH congif entry.
       Host <JAIL NAME>
               User john
               Hostname <IP>
               port <NOT 22>
               IdentityFile ~/.ssh/id_ed25519
  • Stop the old SSH daemon (After you have successfully logged
    in via new SSH port).
    service sshd onestop

Jail is now setup. This should make a good “template” jail you can
use to create new jails from.

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