func RecursiveNS(hostname string) (string, error) {
fulldomain := dns.Fqdn(hostname)
c := &dns.Client{Net: "udp"}
labels := dns.SplitLabels(fulldomain)
return recurseNS(c, fulldomain, labels)
}
func serve(w dns.ResponseWriter, req *dns.Msg, z *dns.Zone) {
if z == nil {
panic("fksd: no zone")
}
m := new(dns.Msg)
// Just NACK ANYs
if req.Question[0].Qtype == dns.TypeANY {
m.SetRcode(req, dns.RcodeServerFailure)
ednsFromRequest(req, m)
w.WriteMsg(m)
return
}
logPrintf("[zone %s] incoming %s %s %d from %s\n", z.Origin, req.Question[0].Name, dns.TypeToString[req.Question[0].Qtype], req.MsgHdr.Id, w.RemoteAddr())
node, exact, ref := z.FindFunc(req.Question[0].Name, func(n interface{}) bool {
return n.(*dns.ZoneData).NonAuth
})
if ref {
logPrintf("[zone %s] referral due\n", z.Origin)
m.SetReply(req)
m.Ns = node.RR[dns.TypeNS]
for _, n := range m.Ns {
if dns.IsSubDomain(n.(*dns.NS).Ns, n.Header().Name) {
findGlue(m, z, n.(*dns.NS).Ns)
}
}
ednsFromRequest(req, m)
w.WriteMsg(m)
return
}
if exact {
exactMatch(w, req, m, z, node)
return
}
// Not an exact match nor an referral
if z.Wildcard > 0 {
lx := dns.SplitLabels(req.Question[0].Name)
wc := "*." + strings.Join(lx[1:], ".")
node, exact = z.Find(wc)
if exact {
logPrintf("[zone %s] wildcard answer\n", z.Origin)
// as exact,but not complete -- only the last part
}
}
nameerror(w, m, req)
return
}
func getQuestionName(z *Zone, req *dns.Msg) string {
lx := dns.SplitLabels(req.Question[0].Name)
ql := lx[0 : len(lx)-z.LenLabels]
return strings.ToLower(strings.Join(ql, "."))
}