(proxy) fix subnet computation using netaddr.IPNetwork, closes...

(proxy) fix subnet computation using netaddr.IPNetwork, closes https://github.com/opnsense/core/issues/1309

src/opnsense/service/templates/OPNsense/Proxy/squid.conf

@@ -101,7 +101,7 @@ ftp_port {{intf_item.subnet}}:{{ OPNsense.proxy.forward.ftpPort }} accel ftp-tra
 {%      for interface in OPNsense.proxy.forward.interfaces.split(",") %}
 {%          for intf_key,intf_item in interfaces.iteritems() %}
 {%              if intf_key == interface and intf_item.ipaddr != 'dhcp' %}
-acl localnet src {{intf_item.ipaddr.split(".")[0:3]|join(".")}}.0/{{intf_item.subnet}} # Possible internal network
+acl localnet src {{ helpers.getIPNetwork(intf_item.ipaddr+'/'+intf_item.subnet)[0].format() }}/{{intf_item.subnet}} # Possible internal network
 {%              endif %}
 {%          endfor %}
 {%          if helpers.exists('virtualip') %}