コード例 #1
0
ファイル: handler.go プロジェクト: yuewko/coredns
// ServeDNS implements the middleware.Handler interface.
func (c Cache) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	state := middleware.State{W: w, Req: r}

	qname := state.Name()
	qtype := state.QType()
	zone := middleware.Zones(c.Zones).Matches(qname)
	if zone == "" {
		return c.Next.ServeDNS(ctx, w, r)
	}

	do := state.Do() // might need more from OPT record?

	if i, ok := c.get(qname, qtype, do); ok {
		resp := i.toMsg(r)
		state.SizeAndDo(resp)
		w.WriteMsg(resp)

		cacheHitCount.WithLabelValues(zone).Inc()
		return dns.RcodeSuccess, nil
	}
	cacheMissCount.WithLabelValues(zone).Inc()

	crr := NewCachingResponseWriter(w, c.cache, c.cap)
	return c.Next.ServeDNS(ctx, crr, r)
}
コード例 #2
0
ファイル: handler.go プロジェクト: yuewko/coredns
// ServeDNS implements the middleware.Handler interface.
func (d Dnssec) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	state := middleware.State{W: w, Req: r}

	do := state.Do()
	qname := state.Name()
	qtype := state.QType()
	zone := middleware.Zones(d.zones).Matches(qname)
	if zone == "" {
		return d.Next.ServeDNS(ctx, w, r)
	}

	// Intercept queries for DNSKEY, but only if one of the zones matches the qname, otherwise we let
	// the query through.
	if qtype == dns.TypeDNSKEY {
		for _, z := range d.zones {
			if qname == z {
				resp := d.getDNSKEY(state, z, do)
				state.SizeAndDo(resp)
				w.WriteMsg(resp)
				return dns.RcodeSuccess, nil
			}
		}
	}

	drr := NewDnssecResponseWriter(w, d)
	return d.Next.ServeDNS(ctx, drr, r)
}
コード例 #3
0
ファイル: handler.go プロジェクト: yuewko/coredns
func (m Metrics) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	state := middleware.State{W: w, Req: r}

	qname := state.QName()
	zone := middleware.Zones(m.ZoneNames).Matches(qname)
	if zone == "" {
		zone = "."
	}

	// Record response to get status code and size of the reply.
	rw := middleware.NewResponseRecorder(w)
	status, err := m.Next.ServeDNS(ctx, rw, r)

	Report(state, zone, rw.Rcode(), rw.Size(), rw.Start())

	return status, err
}
コード例 #4
0
ファイル: responsewriter.go プロジェクト: yuewko/coredns
func (d *DnssecResponseWriter) WriteMsg(res *dns.Msg) error {
	// By definition we should sign anything that comes back, we should still figure out for
	// which zone it should be.
	state := middleware.State{W: d.ResponseWriter, Req: res}

	qname := state.Name()
	zone := middleware.Zones(d.d.zones).Matches(qname)
	if zone == "" {
		return d.ResponseWriter.WriteMsg(res)
	}

	if state.Do() {
		res = d.d.Sign(state, zone, time.Now().UTC())
	}
	state.SizeAndDo(res)

	return d.ResponseWriter.WriteMsg(res)
}
コード例 #5
0
ファイル: kubernetes.go プロジェクト: yuewko/coredns
func kubernetesParse(c *Controller) (kubernetes.Kubernetes, error) {

	/*
	 * TODO: Remove unused state and simplify.
	 * Inflight and Ctx might not be needed. Leaving in place until
	 * we take a pass at API caching and optimizing connector to the
	 * k8s API. Single flight (or limited upper-bound) for inflight
	 * API calls may be desirable.
	 */

	k8s := kubernetes.Kubernetes{
		Proxy: proxy.New([]string{}),
		Ctx:   context.Background(),
		//      Inflight:   &singleflight.Group{},
	}
	var (
		endpoints  = []string{defaultK8sEndpoint}
		template   = defaultNameTemplate
		namespaces = []string{}
	)

	k8s.APIConn = k8sc.NewK8sConnector(endpoints[0])
	k8s.NameTemplate = new(nametemplate.NameTemplate)
	k8s.NameTemplate.SetTemplate(template)

	for c.Next() {
		if c.Val() == "kubernetes" {
			zones := c.RemainingArgs()

			if len(zones) == 0 {
				k8s.Zones = c.ServerBlockHosts
			} else {
				// Normalize requested zones
				k8s.Zones = kubernetes.NormalizeZoneList(zones)
			}

			middleware.Zones(k8s.Zones).FullyQualify()
			if c.NextBlock() {
				// TODO(miek): 2 switches?
				switch c.Val() {
				case "endpoint":
					args := c.RemainingArgs()
					if len(args) == 0 {
						return kubernetes.Kubernetes{}, c.ArgErr()
					}
					endpoints = args
					k8s.APIConn = k8sc.NewK8sConnector(endpoints[0])
				}
				for c.Next() {
					switch c.Val() {
					case "template":
						args := c.RemainingArgs()
						if len(args) == 0 {
							return kubernetes.Kubernetes{}, c.ArgErr()
						}
						template = strings.Join(args, "")
						err := k8s.NameTemplate.SetTemplate(template)
						if err != nil {
							return kubernetes.Kubernetes{}, err
						}
					case "namespaces":
						args := c.RemainingArgs()
						if len(args) == 0 {
							return kubernetes.Kubernetes{}, c.ArgErr()
						}
						namespaces = args
						k8s.Namespaces = &namespaces
					}
				}
			}
			return k8s, nil
		}
	}
	return kubernetes.Kubernetes{}, nil
}
コード例 #6
0
ファイル: handler.go プロジェクト: yuewko/coredns
func (e Etcd) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	state := middleware.State{W: w, Req: r}
	if state.QClass() != dns.ClassINET {
		return dns.RcodeServerFailure, fmt.Errorf("can only deal with ClassINET")
	}
	name := state.Name()
	if e.Debug {
		if debug := isDebug(name); debug != "" {
			e.debug = r.Question[0].Name
			state.Clear()
			state.Req.Question[0].Name = debug
		}
	}

	// We need to check stubzones first, because we may get a request for a zone we
	// are not auth. for *but* do have a stubzone forward for. If we do the stubzone
	// handler will handle the request.
	if e.Stubmap != nil && len(*e.Stubmap) > 0 {
		for zone := range *e.Stubmap {
			if middleware.Name(zone).Matches(name) {
				stub := Stub{Etcd: e, Zone: zone}
				return stub.ServeDNS(ctx, w, r)
			}
		}
	}

	zone := middleware.Zones(e.Zones).Matches(state.Name())
	if zone == "" {
		if e.Next == nil {
			return dns.RcodeServerFailure, nil
		}
		return e.Next.ServeDNS(ctx, w, r)
	}

	var (
		records, extra []dns.RR
		debug          []msg.Service
		err            error
	)
	switch state.Type() {
	case "A":
		records, debug, err = e.A(zone, state, nil)
	case "AAAA":
		records, debug, err = e.AAAA(zone, state, nil)
	case "TXT":
		records, debug, err = e.TXT(zone, state)
	case "CNAME":
		records, debug, err = e.CNAME(zone, state)
	case "PTR":
		records, debug, err = e.PTR(zone, state)
	case "MX":
		records, extra, debug, err = e.MX(zone, state)
	case "SRV":
		records, extra, debug, err = e.SRV(zone, state)
	case "SOA":
		records, debug, err = e.SOA(zone, state)
	case "NS":
		if state.Name() == zone {
			records, extra, debug, err = e.NS(zone, state)
			break
		}
		fallthrough
	default:
		// Do a fake A lookup, so we can distinguish between NODATA and NXDOMAIN
		_, debug, err = e.A(zone, state, nil)
	}

	if e.debug != "" {
		// Substitute this name with the original when we return the request.
		state.Clear()
		state.Req.Question[0].Name = e.debug
	}

	if isEtcdNameError(err) {
		return e.Err(zone, dns.RcodeNameError, state, debug, err)
	}
	if err != nil {
		return e.Err(zone, dns.RcodeServerFailure, state, debug, err)
	}

	if len(records) == 0 {
		return e.Err(zone, dns.RcodeSuccess, state, debug, err)
	}

	m := new(dns.Msg)
	m.SetReply(r)
	m.Authoritative, m.RecursionAvailable, m.Compress = true, true, true
	m.Answer = append(m.Answer, records...)
	m.Extra = append(m.Extra, extra...)
	if e.debug != "" {
		m.Extra = append(m.Extra, servicesToTxt(debug)...)
	}

	m = dedup(m)
	state.SizeAndDo(m)
	m, _ = state.Scrub(m)
	w.WriteMsg(m)
	return dns.RcodeSuccess, nil
}
コード例 #7
0
ファイル: etcd.go プロジェクト: yuewko/coredns
func etcdParse(c *Controller) (etcd.Etcd, bool, error) {
	stub := make(map[string]proxy.Proxy)
	etc := etcd.Etcd{
		Proxy:      proxy.New([]string{"8.8.8.8:53", "8.8.4.4:53"}),
		PathPrefix: "skydns",
		Ctx:        context.Background(),
		Inflight:   &singleflight.Group{},
		Stubmap:    &stub,
	}
	var (
		client        etcdc.KeysAPI
		tlsCertFile   = ""
		tlsKeyFile    = ""
		tlsCAcertFile = ""
		endpoints     = []string{defaultEndpoint}
		stubzones     = false
	)
	for c.Next() {
		if c.Val() == "etcd" {
			etc.Client = client
			etc.Zones = c.RemainingArgs()
			if len(etc.Zones) == 0 {
				etc.Zones = c.ServerBlockHosts
			}
			middleware.Zones(etc.Zones).FullyQualify()
			if c.NextBlock() {
				// TODO(miek): 2 switches?
				switch c.Val() {
				case "stubzones":
					stubzones = true
				case "debug":
					etc.Debug = true
				case "path":
					if !c.NextArg() {
						return etcd.Etcd{}, false, c.ArgErr()
					}
					etc.PathPrefix = c.Val()
				case "endpoint":
					args := c.RemainingArgs()
					if len(args) == 0 {
						return etcd.Etcd{}, false, c.ArgErr()
					}
					endpoints = args
				case "upstream":
					args := c.RemainingArgs()
					if len(args) == 0 {
						return etcd.Etcd{}, false, c.ArgErr()
					}
					for i := 0; i < len(args); i++ {
						h, p, e := net.SplitHostPort(args[i])
						if e != nil && p == "" {
							args[i] = h + ":53"
						}
					}
					endpoints = args
					etc.Proxy = proxy.New(args)
				case "tls": // cert key cacertfile
					args := c.RemainingArgs()
					if len(args) != 3 {
						return etcd.Etcd{}, false, c.ArgErr()
					}
					tlsCertFile, tlsKeyFile, tlsCAcertFile = args[0], args[1], args[2]
				}
				for c.Next() {
					switch c.Val() {
					case "stubzones":
						stubzones = true
					case "debug":
						etc.Debug = true
					case "path":
						if !c.NextArg() {
							return etcd.Etcd{}, false, c.ArgErr()
						}
						etc.PathPrefix = c.Val()
					case "endpoint":
						args := c.RemainingArgs()
						if len(args) == 0 {
							return etcd.Etcd{}, false, c.ArgErr()
						}
						endpoints = args
					case "upstream":
						args := c.RemainingArgs()
						if len(args) == 0 {
							return etcd.Etcd{}, false, c.ArgErr()
						}
						for i := 0; i < len(args); i++ {
							h, p, e := net.SplitHostPort(args[i])
							if e != nil && p == "" {
								args[i] = h + ":53"
							}
						}
						etc.Proxy = proxy.New(args)
					case "tls": // cert key cacertfile
						args := c.RemainingArgs()
						if len(args) != 3 {
							return etcd.Etcd{}, false, c.ArgErr()
						}
						tlsCertFile, tlsKeyFile, tlsCAcertFile = args[0], args[1], args[2]
					}
				}
			}
			client, err := newEtcdClient(endpoints, tlsCertFile, tlsKeyFile, tlsCAcertFile)
			if err != nil {
				return etcd.Etcd{}, false, err
			}
			etc.Client = client
			return etc, stubzones, nil
		}
	}
	return etcd.Etcd{}, false, nil
}
コード例 #8
0
ファイル: file.go プロジェクト: yuewko/coredns
func (f File) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	state := middleware.State{W: w, Req: r}

	if state.QClass() != dns.ClassINET {
		return dns.RcodeServerFailure, errors.New("can only deal with ClassINET")
	}
	qname := state.Name()
	zone := middleware.Zones(f.Zones.Names).Matches(qname)
	if zone == "" {
		if f.Next != nil {
			return f.Next.ServeDNS(ctx, w, r)
		}
		return dns.RcodeServerFailure, errors.New("no next middleware found")
	}
	z, ok := f.Zones.Z[zone]
	if !ok {
		return f.Next.ServeDNS(ctx, w, r)
	}
	if z == nil {
		return dns.RcodeServerFailure, nil
	}
	if r.Opcode == dns.OpcodeNotify {
		if z.isNotify(state) {
			m := new(dns.Msg)
			m.SetReply(r)
			m.Authoritative, m.RecursionAvailable, m.Compress = true, true, true
			state.SizeAndDo(m)
			w.WriteMsg(m)

			log.Printf("[INFO] Notify from %s for %s: checking transfer", state.IP(), zone)
			ok, err := z.shouldTransfer()
			if ok {
				z.TransferIn()
			} else {
				log.Printf("[INFO] Notify from %s for %s: no serial increase seen", state.IP(), zone)
			}
			if err != nil {
				log.Printf("[WARNING] Notify from %s for %s: failed primary check: %s", state.IP(), zone, err)
			}
			return dns.RcodeSuccess, nil
		}
		log.Printf("[INFO] Dropping notify from %s for %s", state.IP(), zone)
		return dns.RcodeSuccess, nil
	}

	if z.Expired != nil && *z.Expired {
		log.Printf("[ERROR] Zone %s is expired", zone)
		return dns.RcodeServerFailure, nil
	}

	if state.QType() == dns.TypeAXFR || state.QType() == dns.TypeIXFR {
		xfr := Xfr{z}
		return xfr.ServeDNS(ctx, w, r)
	}

	answer, ns, extra, result := z.Lookup(qname, state.QType(), state.Do())

	m := new(dns.Msg)
	m.SetReply(r)
	m.Authoritative, m.RecursionAvailable, m.Compress = true, true, true
	m.Answer, m.Ns, m.Extra = answer, ns, extra

	switch result {
	case Success:
	case NoData:
	case NameError:
		m.Rcode = dns.RcodeNameError
	case Delegation:
		m.Authoritative = false
	case ServerFailure:
		return dns.RcodeServerFailure, nil
	}

	state.SizeAndDo(m)
	m, _ = state.Scrub(m)
	w.WriteMsg(m)
	return dns.RcodeSuccess, nil
}
コード例 #9
0
ファイル: handler.go プロジェクト: yuewko/coredns
func (k Kubernetes) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
	log.Printf("[debug] here entering ServeDNS: ctx:%v dnsmsg:%v\n", ctx, r)

	state := middleware.State{W: w, Req: r}
	if state.QClass() != dns.ClassINET {
		return dns.RcodeServerFailure, fmt.Errorf("can only deal with ClassINET")
	}

	// Check that query matches one of the zones served by this middleware,
	// otherwise delegate to the next in the pipeline.
	zone := middleware.Zones(k.Zones).Matches(state.Name())
	if zone == "" {
		if k.Next == nil {
			return dns.RcodeServerFailure, nil
		}
		return k.Next.ServeDNS(ctx, w, r)
	}

	m := new(dns.Msg)
	m.SetReply(r)
	m.Authoritative, m.RecursionAvailable, m.Compress = true, true, true

	var (
		records, extra []dns.RR
		err            error
	)
	switch state.Type() {
	case "A":
		records, err = k.A(zone, state, nil)
	case "AAAA":
		records, err = k.AAAA(zone, state, nil)
	case "TXT":
		records, err = k.TXT(zone, state)
		// TODO: change lookup to return appropriate error. Then add code below
		// this switch to check for the error and return not implemented.
		//return dns.RcodeNotImplemented, nil
	case "CNAME":
		records, err = k.CNAME(zone, state)
	case "MX":
		records, extra, err = k.MX(zone, state)
	case "SRV":
		records, extra, err = k.SRV(zone, state)
	case "SOA":
		records = []dns.RR{k.SOA(zone, state)}
	case "NS":
		if state.Name() == zone {
			records, extra, err = k.NS(zone, state)
			break
		}
		fallthrough
	default:
		// Do a fake A lookup, so we can distinguish betwen NODATA and NXDOMAIN
		_, err = k.A(zone, state, nil)
	}
	if isKubernetesNameError(err) {
		return k.Err(zone, dns.RcodeNameError, state)
	}
	if err != nil {
		return dns.RcodeServerFailure, err
	}

	if len(records) == 0 {
		return k.Err(zone, dns.RcodeSuccess, state)
	}

	m.Answer = append(m.Answer, records...)
	m.Extra = append(m.Extra, extra...)

	m = dedup(m)
	state.SizeAndDo(m)
	m, _ = state.Scrub(m)
	w.WriteMsg(m)
	return dns.RcodeSuccess, nil
}