ipset alternative or some kind of smart idea for wildcards

Senior programmer here but hate the linux networking limitations which make things difficult compared to all programming languages. Practically I need to make **policy based routing** that allows specific lan ip addresses to pick specific outgoing interface (let's say eth5). Even ipset is not powerful enough in my situation. I want to allow all lan ips that first octate is "10" and the last octate is ending up with "9". That would be 10.*.*.??9 or in javascript if(ip.match("\10\..*\.(\d+9|9)\g")) ...USE eth5 Does anyone knows some kind of trick to achive that ? That would be probably thounsands of IP CIDR if we have to stick with CIDR, which is insanity. Thanks