MVC/Firewall/Util - add CIDRToMask()

opnsense · May 10, 2023 · d633cd9 · d633cd9
1 parent 271525f
commit d633cd9
Showing 1 changed file with 10 additions and 0 deletions.
diff --git a/src/opnsense/mvc/app/library/OPNsense/Firewall/Util.php b/src/opnsense/mvc/app/library/OPNsense/Firewall/Util.php
@@ -339,6 +339,16 @@ public static function calcRuleHash($rule)
         return md5(json_encode($rule));
     }
 
+    /**
+     * convert ipv4 cidr to netmask e.g. 24 --> 255.255.255.0
+     * @param int $bits ipv4 bits
+     * @return string netmask
+     */
+    public static function CIDRToMask($bits)
+    {
+        return long2ip(0xFFFFFFFF << (32 - $bits));
+    }
+
     /**
      * Find the smallest possible subnet mask for given IP range
      * @param array ips (start, end)