IPv4 and IPv6 collision

[fishnux]

There seems to be a collision with the following specific CIDRs:

• 42.0.0.0/22
• 2a00::/22

package main

import (
	"fmt"
	"github.com/asergeyev/nradix"
)

func main() {
	tr := nradix.NewTree(0)
	
	err := tr.AddCIDR("42.0.0.0/22", "Got 42.0.0.0/22")
	if err != nil {
		fmt.Print(err)
	}

	inf, err := tr.FindCIDR("2a00::/22")
	if err != nil {
		fmt.Print(err)
	}
	
	fmt.Print(inf)
}

https://play.golang.org/p/xQiaBZQZkWi

[lior-k]

yes, I'm encountering the same issue.
I'm feeding the tree IPV4 CIDRs only and when I ask on an IPv6 - it finds it in the tree.
Can we please have a fix for it?

[misiek08]

I did some simplification works on branch in my fork - replacing current implementation for IPv4 with IPv6-mapped addresses.
The only problem for some of you can be performance - simple IPv4 Find (e.g. t.FindCIDR("73.26.28.24") in tree with 1 million of /24 entries) takes 200ns/op instead of 36ns/op.

When I'll find again some free time I'll try to look into it - I used net package for IPv4 parsing and it is a lot slower than custom made bit mangling, of course :)

[asergeyev]

It's generally tricky to mix v4 and v6 in prefix tree... why not to keep them in separate ones? Alternatively you could prepend proto byte to your ips so it'll prefix-out and not add much memory