Strengthen the validity criterion. Empty rules shouldn't happen anyway.
Strengthen the validity criterion. Empty rules shouldn't happen anyway.

jcaesar/Iptables_Semantics,jcaesar/Iptables_Semantics,diekmann/Iptables_Semantics,diekmann/Iptables_Semantics,jcaesar/Iptables_Semantics,diekmann/Iptables_Semantics