Add an option to disable .meship resolver

cmd/meshnamed/main.go

@@ -38,7 +38,7 @@ func loadConfig(s *meshname.MeshnameServer, confPath string) error {
 
 var (
 	genconf, subdomain, useconffile, listenAddr, networksconf string
-	debug, allowRemote                                        bool
+	debug, noMeshIP, allowRemote                              bool
 )
 
 func init() {
@@ -47,6 +47,7 @@ func init() {
 	flag.StringVar(&useconffile, "useconffile", "", "run daemon with a config file")
 	flag.StringVar(&listenAddr, "listenaddr", "[::1]:53535", "address to listen on")
 	flag.StringVar(&networksconf, "networks", "ygg=200::/7,cjd=fc00::/8,meshname=::/0", "TLD=subnet list separated by comma")
+	flag.BoolVar(&noMeshIP, "nomeship", false, "disable .meship resolver")
 	flag.BoolVar(&allowRemote, "allowremote", false, "allow remote queries from any IP address")
 	flag.BoolVar(&debug, "debug", false, "enable debug logging")
 }
@@ -77,7 +78,7 @@ func main() {
 		logger.Fatalln(err)
 	}
 
-	s := meshname.New(logger, listenAddr, networks, allowRemote)
+	s := meshname.New(logger, listenAddr, networks, !noMeshIP, allowRemote)
 	if useconffile != "" {
 		if err := loadConfig(s, useconffile); err != nil {
 			logger.Fatalln(err)

pkg/meshname/server.go

@@ -16,6 +16,7 @@ type MeshnameServer struct {
 	dnsClient    *dns.Client
 	dnsServer    *dns.Server
 	networks     map[string]*net.IPNet
+	enableMeshIP bool
 	allowRemote  bool
 
 	dnsRecordsLock sync.RWMutex
@@ -26,7 +27,7 @@ type MeshnameServer struct {
 }
 
 // New is a constructor for MeshnameServer
-func New(log *log.Logger, listenAddr string, networks map[string]*net.IPNet, allowRemote bool) *MeshnameServer {
+func New(log *log.Logger, listenAddr string, networks map[string]*net.IPNet, enableMeshIP bool, allowRemote bool) *MeshnameServer {
 	dnsClient := new(dns.Client)
 	dnsClient.Timeout = 5000000000 // increased 5 seconds timeout
 
@@ -36,6 +37,7 @@ func New(log *log.Logger, listenAddr string, networks map[string]*net.IPNet, all
 		dnsRecords:   make(map[string][]dns.RR),
 		networks:     networks,
 		dnsClient:    dnsClient,
+		enableMeshIP: enableMeshIP,
 		allowRemote:  allowRemote,
 	}
 }
@@ -64,9 +66,14 @@ func (s *MeshnameServer) Start() error {
 			NotifyStartedFunc: func() { close(waitStarted) },
 		}
 		for tld, subnet := range s.networks {
-			dns.HandleFunc(tld, s.handleRequest)
+			dns.HandleFunc(tld, s.handleMeshnameRequest)
 			s.log.Debugln("Handling:", tld, subnet)
 		}
+		if s.enableMeshIP {
+			dns.HandleFunc("meship", s.handleMeshIPRequest)
+			s.log.Debugln("Handling: meship ::/0")
+		}
+
 		go func() {
 			if err := s.dnsServer.ListenAndServe(); err != nil {
 				s.log.Fatalln("MeshnameServer failed to start:", err)
@@ -88,7 +95,7 @@ func (s *MeshnameServer) ConfigureDNSRecords(dnsRecords map[string][]dns.RR) {
 	s.dnsRecordsLock.Unlock()
 }
 
-func (s *MeshnameServer) handleRequest(w dns.ResponseWriter, r *dns.Msg) {
+func (s *MeshnameServer) handleMeshnameRequest(w dns.ResponseWriter, r *dns.Msg) {
 	var remoteLookups = make(map[string][]dns.Question)
 	m := new(dns.Msg)
 	m.SetReply(r)
@@ -146,6 +153,34 @@ func (s *MeshnameServer) handleRequest(w dns.ResponseWriter, r *dns.Msg) {
 	}
 }
 
+func (s *MeshnameServer) handleMeshIPRequest(w dns.ResponseWriter, r *dns.Msg) {
+	m := new(dns.Msg)
+	m.SetReply(r)
+
+	for _, q := range r.Question {
+		labels := dns.SplitDomainName(q.Name)
+		// resolve only 2nd level domains and AAAA type
+		if len(labels) != 2 || q.Qtype != dns.TypeAAAA || q.Qclass != dns.ClassINET {
+			s.log.Debugln("Error: invalid resource requested")
+			continue
+		}
+
+		if resolvedAddr, err := IPFromDomain(&labels[0]); err == nil {
+			answer := new(dns.AAAA)
+			answer.Hdr = dns.RR_Header{Name: q.Name, Rrtype: dns.TypeAAAA, Class: dns.ClassINET, Ttl: 3600}
+			answer.AAAA = resolvedAddr
+
+			m.Answer = append(m.Answer, answer)
+		} else {
+			s.log.Debugln(err)
+		}
+	}
+
+	if err := w.WriteMsg(m); err != nil {
+		s.log.Debugln("Error writing response:", err)
+	}
+}
+
 func (s *MeshnameServer) isRemoteLookupAllowed(addr net.Addr) bool {
 	// TODO prefix whitelists ?
 	if s.allowRemote {