define netif = enp0s3
define dmzif = enp0s8
define lanif = enp0s9

define lan-ntw = 10.0.0.0/24

define proxy = 10.121.38.1
define dns = {10.121.38.7 , 10.121.38.8}
define proxyport = 8080
define dmznet = 172.16.0.1-172.16.0.254

define firewall = 192.168.0.120
define ipdmz = 172.16.0.254
define iplan = 10.0.0.254

table ip ipfilter{
	chain prerouting {
        type filter hook prerouting priority filter; policy drop;
		ct state established, related accept
		icmp type echo-reply accept
		icmp type echo-request iif {$lanif} ip daddr $dmznet accept
		icmp type echo-request iif {$lanif} ip daddr {$iplan} accept
        tcp dport 20 accept
        tcp dport 21 accept
        tcp dport {80, 443} ip saddr $lan-ntw accept
		tcp sport {80, 443} ip saddr $lan-ntw accept
		tcp dport 22 accept
		ip saddr $proxy tcp dport {80, 443} accept
        }

	chain system_in {
        type filter hook input priority filter; policy drop;
		ct state established, related accept
		icmp type echo-reply accept
		icmp type echo-request iif {$lanif} accept
        tcp dport 20 accept
        tcp dport 21 accept
        tcp dport {80, 443} accept
        tcp dport 22 accept
		ip saddr $proxy tcp dport {80, 443} accept
        }

 	chain routing {
        type filter hook forward priority filter; policy drop;
		ct state established, related accept
        icmp type echo-request iif {$lanif} oif {$dmzif} accept
		icmp type echo-reply iif {$dmzif} oif {$lanif} accept
        tcp dport {80, 443} ip saddr $lan-ntw accept
		tcp sport {80, 443} ip saddr $lan-ntw accept
	}

 	chain system_out {
        type filter hook output priority filter; policy drop;
        ip daddr $dns accept
        ip daddr $proxy tcp dport $proxyport accept
		icmp type echo-reply oif {$lanif} accept
		icmp type echo-request accept
        tcp dport 20 accept
		tcp sport 20 accept
        tcp dport 21 accept
		tcp sport 21 accept
        tcp dport {80, 443} accept
		tcp sport {80, 443} accept
		tcp sport 22 accept
        }

	chain postrouting {
        type filter hook postrouting priority filter; policy drop;
		ct state established, related accept
		ip daddr $dns accept
		ip daddr $proxy tcp dport $proxyport accept
		icmp type echo-request ip saddr {$iplan, $ipdmz, $firewall} accept
		icmp type echo-reply iif {$dmzif}  oif {$lanif} accept
		icmp type echo-request iif {$lanif} oif {$dmzif} accept
		icmp type echo-request ip saddr $iplan oif $lanif accept
        tcp dport 20 accept
        tcp sport 20 accept
        tcp dport 21 accept
        tcp sport 21 accept
        tcp dport {80, 443} accept
		tcp sport {80, 443} accept
		tcp sport 22 accept
	}

	chain pre_nat {
		type nat hook prerouting priority filter; policy accept;
	}

	chain post_nat {
        type nat hook postrouting priority filter; policy accept;
		ip saddr $lan-ntw oif $netif snat $firewall
	}
}