# cidranger Fast IP to belonging CIDR block(s) lookup using trie implementation, e.g. 192.168.0.1 is contained in 192.168.0.0/24 [![GoDoc Reference](https://img.shields.io/badge/godoc-reference-5272B4.svg?style=flat-square)](https://godoc.org/github.com/yl2chen/cidranger) [![Build Status](https://img.shields.io/travis/yl2chen/cidranger.svg?branch=master&style=flat-square)](https://travis-ci.org/yl2chen/cidranger) ### Usage Configure imports. ``` import ( "net", "github.com/yl2chen/cidranger" ) ``` Creates a new ranger inmplemented using Level-Path-Compressed (path compressed capability coming soon) trie. ``` ranger := NewLPCTrieRanger() ``` Inserts CIDR blocks. ``` _, network1, _ := net.ParseCIDR("192.168.1.0/24") _, network2, _ := net.ParseCIDR("128.168.1.0/24") ranger.Insert(*network1) ranger.Insert(*network2) ``` The prefix trie can be visualized as: ``` 0.0.0.0/0 (target_pos:31:has_entry:false) | 1--> 128.0.0.0/1 (target_pos:30:has_entry:false) | | 0--> 128.168.1.0/24 (target_pos:7:has_entry:true) | | 1--> 192.168.1.0/24 (target_pos:7:has_entry:true) ``` To test if given IP is contained in constructed ranger, IPv6 is not currently supported, an error will be returend if called with an IPv6 ip. ``` contains, err = ranger.Contains(net.ParseIP("128.168.1.0")) // returns true, nil contains, err = ranger.Contains(net.ParseIP("192.168.2.0")) // returns false, nil ``` To get all the networks given is contained in, ``` containingNetworks, err = ranger.ContainingNetworks(net.ParseIP("128.168.1.0")) ``` ### Benchmark results comparing hit/miss for LPC trie vs brute force implementation, using AWS published ip ranges. ``` BenchmarkLPCTrieHitUsingAWSRanges-4 5000000 314.0 ns/op BenchmarkBruteRangerHitUsingAWSRanges-4 100000 14005.0 ns/op BenchmarkLPCTrieMissUsingAWSRanges-4 20000000 82.1 ns/op BenchmarkBruteRangerMissUsingAWSRanges-4 50000 24422.0 ns/op ``` ### TODO * Implement level-compressed component of LPC trie ranger. * Add support for IPv6