Hi Chris,
Albert is referring to the linux fonzfun_plug install which is, at this time, a bit over your head. Given where you are at, how about simply adding "nobody" or "Nobody" or both as user(s) with rather secure passwords and then use the "deny access" as rights on top of this. You could do this quickly with the 320's GUI without any further knowledge and then just keep checking the logs to see if you are still being breached. Good luck