1package dnsutil
2
3import "github.com/miekg/dns"
4
5// DuplicateCNAME returns true if r already exists in records.
6func DuplicateCNAME(r *dns.CNAME, records []dns.RR) bool {
7	for _, rec := range records {
8		if v, ok := rec.(*dns.CNAME); ok {
9			if v.Target == r.Target {
10				return true
11			}
12		}
13	}
14	return false
15}
16