Add support for Checkmk monitoring service.

ip6t-firewall-gateway

@@ -3665,6 +3665,56 @@ else
 fi
 
 
+# ---
+# - Checkmk Monitoring Service Gateway
+# ---
+
+echononl "\t\tCheckmk Monitoring Service Gateway (only local network)"
+
+if $checkmk_service_gateway ; then
+
+   for _dev in ${local_if_arr[@]} ; do
+      $ip6t -A OUTPUT -o $_dev -p tcp --dport $checkmk_local_port -m conntrack --ctstate NEW -j ACCEPT
+   done
+
+   echo_done
+else
+   echo_skipped
+fi
+
+
+# ---
+# - Checkmk Service local Networks
+# ---
+
+echononl "\t\tCheckmk Monitoring Service local Networks"
+if [[ ${#checkmk_local_server_ip_arr[@]} -gt 0 ]] ; then
+   for _ip in ${checkmk_local_server_ip_arr[@]} ; do
+      $ip6t -A INPUT -s $_ip -p tcp --dport $checkmk_local_port -m conntrack --ctstate NEW -j ACCEPT
+
+		if $kernel_forward_between_interfaces && ! $permit_between_local_networks ; then
+         for _dev in ${local_if_arr[@]} ; do
+            if ! $permit_between_local_networks ; then
+               $ip6t -A FORWARD -i $_dev -s $_ip -p tcp --dport $checkmk_local_port -m conntrack --ctstate NEW -j ACCEPT
+            fi
+         done
+      fi
+
+      # - Rule is needed if (local) interface aliases in use (like eth0:1)
+      # -
+      if $kernel_forward_between_interfaces && $local_alias_interfaces ; then
+         $ip6t -A FORWARD -p tcp -d $_ip --sport $checkmk_local_port --tcp-flag ACK ACK -j ACCEPT
+         $ip6t -A FORWARD -p tcp -s $_ip --dport $checkmk_local_port --tcp-flag ACK ACK -j ACCEPT
+      fi
+
+   done
+
+   echo_done
+else
+   echo_skipped
+fi
+
+
 # ---
 # - XyMon local service
 # ---