func marshalCanonicalCAASet(set []*dns.CAA) ([]byte, error) {
var err error
offset, size := 0, 0
sortedSet := caaSet(set)
sort.Sort(sortedSet)
for _, rr := range sortedSet {
size += dns.Len(rr)
}
tbh := make([]byte, size)
for _, rr := range sortedSet {
ttl := rr.Hdr.Ttl
rr.Hdr.Ttl = 0 // only variable that should jitter
offset, err = dns.PackRR(rr, tbh, offset, nil, false)
if err != nil {
return nil, err
}
rr.Hdr.Ttl = ttl
}
return tbh, nil
}
// Serve an AXFR (and fallback of IXFR) as well.
func (x Xfr) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
state := middleware.State{W: w, Req: r}
if !x.TransferAllowed(state) {
return dns.RcodeServerFailure, nil
}
if state.QType() != dns.TypeAXFR && state.QType() != dns.TypeIXFR {
return 0, fmt.Errorf("xfr called with non transfer type: %d", state.QType())
}
records := x.All()
if len(records) == 0 {
return dns.RcodeServerFailure, nil
}
ch := make(chan *dns.Envelope)
defer close(ch)
tr := new(dns.Transfer)
go tr.Out(w, r, ch)
j, l := 0, 0
records = append(records, records[0]) // add closing SOA to the end
log.Printf("[INFO] Outgoing transfer of %d records of zone %s to %s started", len(records), x.origin, state.IP())
for i, r := range records {
l += dns.Len(r)
if l > transferLength {
ch <- &dns.Envelope{RR: records[j:i]}
l = 0
j = i
}
}
if j < len(records) {
ch <- &dns.Envelope{RR: records[j:]}
}
w.Hijack()
// w.Close() // Client closes connection
return dns.RcodeSuccess, nil
}