nsec-bug.go

package main

import (
	"fmt"
	"github.com/miekg/dns"
)

func main() {
	msg := dns.Msg{Compress: true}

	ownername := "some-very-long-ownername.com."
	ns := dns.NS{
		Hdr: dns.RR_Header{
			Name:   ownername,
			Rrtype: dns.TypeNS,
			Class:  dns.ClassINET,
		},
		Ns: "ns1.server.com.",
	}
	msg.Answer = append(msg.Answer, &ns)

	nsec := dns.NSEC{
		Hdr: dns.RR_Header{
			Name:   ownername,
			Rrtype: dns.TypeNSEC,
			Class:  dns.ClassINET,
		},
		NextDomain: "a.com.",
		TypeBitMap: []uint16{dns.TypeNS, dns.TypeNSEC},
	}
	msg.Answer = append(msg.Answer, &nsec)

	// Pack msg and then unpack into msg2
	msgBuffer, _ := msg.Pack()
	msg2 := dns.Msg{}
	msg2.Unpack(msgBuffer)

	// Print NSEC RR for both cases
	fmt.Println(msg.Answer[1])
	fmt.Println(msg2.Answer[1])
}