Check to see if an IPv4 Address is in CIDR Range in a ServiceNow Script Include

CidrUtil.js

var CidrUtil = Class.create();
CidrUtil.prototype = {
	initialize: function() {
	},
	ipIsInCidr : function(ip, cidr) {
		
		var cidrIp = cidr.split('/')[0];
		
		var cidrSm = cidr.split('/')[1];
		
		return (this.IPnumber(ip) & this.IPmask(cidrSm)) == this.IPnumber(cidrIp);
			
	},
	
	IPnumber : function (IPaddress) {
		
		var ip = IPaddress.match(/^(\d+)\.(\d+)\.(\d+)\.(\d+)$/);
		
		if(ip) {
			
			return (+ip[1]<<24) + (+ip[2]<<16) + (+ip[3]<<8) + (+ip[4]);
				
		}
		
		// else ... ?
		
		return null;
			
	},
	
	
	IPmask : function(maskSize) {
		
		return -1<<(32-maskSize);
				
	},
	
	type: 'CidrUtil'
};

//https://community.servicenow.com/community?id=community_question&sys_id=54b1cb69db98dbc01dcaf3231f96198a
/* Usage Example
var ip = '192.168.1.4';
var cidr = '192.168.1.0/24';
var cu = new CidrUtil();
gs.log(cu.ipIsInCidr(ip, cidr)); //Return true
*/