Esempio n. 1
0
func (e Etcd) NS(zone string, state middleware.State) (records, extra []dns.RR, debug []msg.Service, err error) {
	// NS record for this zone live in a special place, ns.dns.<zone>. Fake our lookup.
	// only a tad bit fishy...
	old := state.QName()

	state.Clear()
	state.Req.Question[0].Name = "ns.dns." + zone
	services, debug, err := e.records(state, false)
	if err != nil {
		return nil, nil, debug, err
	}
	// ... and reset
	state.Req.Question[0].Name = old

	for _, serv := range services {
		ip := net.ParseIP(serv.Host)
		switch {
		case ip == nil:
			return nil, nil, debug, fmt.Errorf("NS record must be an IP address: %s", serv.Host)
		case ip.To4() != nil:
			serv.Host = msg.Domain(serv.Key)
			records = append(records, serv.NewNS(state.QName()))
			extra = append(extra, serv.NewA(serv.Host, ip.To4()))
		case ip.To4() == nil:
			serv.Host = msg.Domain(serv.Key)
			records = append(records, serv.NewNS(state.QName()))
			extra = append(extra, serv.NewAAAA(serv.Host, ip.To16()))
		}
	}
	return records, extra, debug, nil
}
Esempio n. 2
0
// MX returns MX records from etcd.
// If the Target is not a name but an IP address, a name is created on the fly.
func (e Etcd) MX(zone string, state middleware.State) (records, extra []dns.RR, debug []msg.Service, err error) {
	services, debug, err := e.records(state, false)
	if err != nil {
		return nil, nil, debug, err
	}

	lookup := make(map[string]bool)
	for _, serv := range services {
		if !serv.Mail {
			continue
		}
		ip := net.ParseIP(serv.Host)
		switch {
		case ip == nil:
			mx := serv.NewMX(state.QName())
			records = append(records, mx)
			if _, ok := lookup[mx.Mx]; ok {
				break
			}

			lookup[mx.Mx] = true

			if !dns.IsSubDomain(zone, mx.Mx) {
				m1, e1 := e.Proxy.Lookup(state, mx.Mx, dns.TypeA)
				if e1 == nil {
					extra = append(extra, m1.Answer...)
				}
				m1, e1 = e.Proxy.Lookup(state, mx.Mx, dns.TypeAAAA)
				if e1 == nil {
					// If we have seen CNAME's we *assume* that they are already added.
					for _, a := range m1.Answer {
						if _, ok := a.(*dns.CNAME); !ok {
							extra = append(extra, a)
						}
					}
				}
				break
			}
			// Internal name
			state1 := copyState(state, mx.Mx, dns.TypeA)
			addr, debugAddr, e1 := e.A(zone, state1, nil)
			if e1 == nil {
				extra = append(extra, addr...)
				debug = append(debug, debugAddr...)
			}
			// e.AAAA as well
		case ip.To4() != nil:
			serv.Host = msg.Domain(serv.Key)
			records = append(records, serv.NewMX(state.QName()))
			extra = append(extra, serv.NewA(serv.Host, ip.To4()))
		case ip.To4() == nil:
			serv.Host = msg.Domain(serv.Key)
			records = append(records, serv.NewMX(state.QName()))
			extra = append(extra, serv.NewAAAA(serv.Host, ip.To16()))
		}
	}
	return records, extra, debug, nil
}
Esempio n. 3
0
// Look in .../dns/stub/<zone>/xx for msg.Services. Loop through them
// extract <zone> and add them as forwarders (ip:port-combos) for
// the stub zones. Only numeric (i.e. IP address) hosts are used.
// Only the first zone configured on e is used for the lookup.
func (e *Etcd) updateStubZones() {
	zone := e.Zones[0]
	services, err := e.Records(stubDomain+"."+zone, false)
	if err != nil {
		return
	}

	stubmap := make(map[string]proxy.Proxy)
	// track the nameservers on a per domain basis, but allow a list on the domain.
	nameservers := map[string][]string{}

	for _, serv := range services {
		if serv.Port == 0 {
			serv.Port = 53
		}
		ip := net.ParseIP(serv.Host)
		if ip == nil {
			log.Printf("[WARNING] Non IP address stub nameserver: %s", serv.Host)
			continue
		}

		domain := msg.Domain(serv.Key)
		labels := dns.SplitDomainName(domain)

		// If the remaining name equals any of the zones we have, we ignore it.
		for _, z := range e.Zones {
			// Chop of left most label, because that is used as the nameserver place holder
			// and drop the right most labels that belong to zone.
			// We must *also* chop of dns.stub. which means cutting two more labels.
			domain = dns.Fqdn(strings.Join(labels[1:len(labels)-dns.CountLabel(z)-2], "."))
			if domain == z {
				log.Printf("[WARNING] Skipping nameserver for domain we are authoritative for: %s", domain)
				continue
			}
			nameservers[domain] = append(nameservers[domain], net.JoinHostPort(serv.Host, strconv.Itoa(serv.Port)))
		}
	}
	for domain, nss := range nameservers {
		stubmap[domain] = proxy.New(nss)
	}
	// atomic swap (at least that's what we hope it is)
	if len(stubmap) > 0 {
		e.Stubmap = &stubmap
	}
	return
}
Esempio n. 4
0
// SRV returns SRV records from etcd.
// If the Target is not a name but an IP address, a name is created on the fly.
func (e Etcd) SRV(zone string, state middleware.State) (records, extra []dns.RR, debug []msg.Service, err error) {
	services, debug, err := e.records(state, false)
	if err != nil {
		return nil, nil, nil, err
	}

	// Looping twice to get the right weight vs priority
	w := make(map[int]int)
	for _, serv := range services {
		weight := 100
		if serv.Weight != 0 {
			weight = serv.Weight
		}
		if _, ok := w[serv.Priority]; !ok {
			w[serv.Priority] = weight
			continue
		}
		w[serv.Priority] += weight
	}
	lookup := make(map[string]bool)
	for _, serv := range services {
		w1 := 100.0 / float64(w[serv.Priority])
		if serv.Weight == 0 {
			w1 *= 100
		} else {
			w1 *= float64(serv.Weight)
		}
		weight := uint16(math.Floor(w1))
		ip := net.ParseIP(serv.Host)
		switch {
		case ip == nil:
			srv := serv.NewSRV(state.QName(), weight)
			records = append(records, srv)

			if _, ok := lookup[srv.Target]; ok {
				break
			}

			lookup[srv.Target] = true

			if !dns.IsSubDomain(zone, srv.Target) {
				m1, e1 := e.Proxy.Lookup(state, srv.Target, dns.TypeA)
				if e1 == nil {
					extra = append(extra, m1.Answer...)
				}
				m1, e1 = e.Proxy.Lookup(state, srv.Target, dns.TypeAAAA)
				if e1 == nil {
					// If we have seen CNAME's we *assume* that they are already added.
					for _, a := range m1.Answer {
						if _, ok := a.(*dns.CNAME); !ok {
							extra = append(extra, a)
						}
					}
				}
				break
			}
			// Internal name, we should have some info on them, either v4 or v6
			// Clients expect a complete answer, because we are a recursor in their view.
			state1 := copyState(state, srv.Target, dns.TypeA)
			addr, debugAddr, e1 := e.A(zone, state1, nil)
			if e1 == nil {
				extra = append(extra, addr...)
				debug = append(debug, debugAddr...)
			}
			// e.AAA(zone, state1, nil) as well...?
		case ip.To4() != nil:
			serv.Host = msg.Domain(serv.Key)
			srv := serv.NewSRV(state.QName(), weight)

			records = append(records, srv)
			extra = append(extra, serv.NewA(srv.Target, ip.To4()))
		case ip.To4() == nil:
			serv.Host = msg.Domain(serv.Key)
			srv := serv.NewSRV(state.QName(), weight)

			records = append(records, srv)
			extra = append(extra, serv.NewAAAA(srv.Target, ip.To16()))
		}
	}
	return records, extra, debug, nil
}