Ajout des configs du firewall jusqu'à l'étape 6

sisr1/tp06-firewall/fw_part4.nft

@@ -0,0 +1,54 @@
+define netif = enp0s3
+define lanif = enp0s8
+define dmzif = enp0s9
+
+define netip = 192.168.0.130
+define lanip = 172.16.0.254
+define dmzip = 172.17.0.254
+
+define lan-ntw = 172.16.0.1-172.16.0.254
+define dmz-ntw = 172.17.0.1-172.17.0.254
+
+table ip ipfilter {
+    chain prerouting {
+        type filter hook prerouting priority filter; policy drop;
+        ct state established,related accept
+        tcp dport 22 accept
+        icmp type echo-request iif $lanif accept
+        icmp type echo-reply iif {$lanif, $dmzif} accept
+    }
+    chain system_in {
+        type filter hook input priority filter; policy drop;
+        ct state established,related accept
+        tcp dport 22 accept
+        icmp type echo-request iif $lanif accept
+        icmp type echo-reply accept
+        udp sport 53 accept  # Ajout pour les réponses DNS
+    }
+    chain routing {
+        type filter hook forward priority filter; policy drop;
+        icmp type echo-request iif $lanif oif $dmzif accept
+        icmp type echo-reply iif $dmzif oif $lanif accept
+        udp sport 53 accept  # Ajout pour les réponses DNS
+    }
+    chain system_out {
+        type filter hook output priority filter; policy drop;
+        tcp sport 22 accept
+        udp dport 53 accept
+        tcp dport {80, 443} accept
+        tcp dport {20, 21} accept
+        tcp dport 8080 accept
+        icmp type echo-request accept
+        icmp type echo-reply oif $lanif accept
+    }
+    chain postrouting {
+        type filter hook postrouting priority filter; policy drop;
+        tcp sport 22 accept
+        udp dport 53 accept
+        tcp sport {80, 443} accept
+        tcp sport {20, 21} accept
+        tcp dport 8080 accept
+        icmp type echo-request oif {$lanif, $dmzif} accept
+        icmp type echo-reply oif $lanif accept
+    }
+}