This tutorial shows how to set up an easy parental control facility, with help of DansGuardian, Privoxy and a few firewall rules. I've tested it and so far, it seems to be working for most part.
There are, however, some things I fail to understand. Namely, in this tutorial we are told to set up, among others, following firewall rules:
sudo iptables -A OUTPUT -p tcp -m multiport --dports 80,443 -m owner --uid-owner privoxy -j ACCEPT
sudo iptables -A OUTPUT -o lo -p tcp --dport 8118 -m owner --uid-owner dansguardian -j ACCEPT
Wait... -m owner --uid-owner dansguardian
, -m owner --uid-owner privoxy
??
I always thought that uids can be either usernames or groups, which can be assigned to users, and not processes or files? I must've been wrong...
This is even more confusing because getent group
shows an entry for dansguardian
, but not for privoxy
; so I'm not sure what does this --uid-owner privoxy
refers to, since privoxy
is neither a user nor group.
Thanks in advance for explaining this to me.