func (wb *workbench) dnsHandler(w dns.ResponseWriter, r *dns.Msg) {
wb.mu.RLock()
defer wb.mu.RUnlock()
defer w.Close()
m := new(dns.Msg)
m.SetReply(r)
m.Compress = wb.compression
if len(r.Question) > 1 || r.Rcode != dns.OpcodeQuery {
m.Rcode = dns.RcodeNotImplemented
} else if len(r.Question) == 0 {
m.Rcode = dns.RcodeFormatError
}
if m.Rcode == dns.RcodeFormatError || m.Rcode == dns.RcodeNotImplemented {
w.WriteMsg(m)
return
}
q := &r.Question[0]
wb.l.Printf("Received query for [%s] %s\n", dns.TypeToString[q.Qtype], q.Name)
allRecords, present := wb.z[q.Name]
if !present {
m.Rcode = dns.RcodeNameError
w.WriteMsg(m)
return
}
if auth, present := wb.a[q.Name]; present {
m.Authoritative = true
m.Ns = append(m.Ns, *auth)
}
qRecords, present := allRecords[q.Qtype]
if !present {
m.Rcode = dns.RcodeNXRrset
w.WriteMsg(m)
return
}
m.Answer = append(m.Answer, qRecords...)
w.WriteMsg(m)
return
}
