feat: obtain external address for rendezvous (#2333)

* feat: obtain external address for rendezvous
If the ext ip returned by geth is 127.0.0.1, it will attempt to obtain the external IP address via rendezvous and use that to register the ens record later
* fix: failing test
* fix: code review, and adding external ip address to logs

discovery/rendezvous.go

@@ -104,7 +104,7 @@ func (r *Rendezvous) Stop() error {
 	return nil
 }
 
-func (r *Rendezvous) MakeRecord() (record enr.Record, err error) {
+func (r *Rendezvous) MakeRecord(srv *ma.Multiaddr) (record enr.Record, err error) {
 	r.recordMu.Lock()
 	defer r.recordMu.Unlock()
 	if r.record != nil {
@@ -116,7 +116,27 @@ func (r *Rendezvous) MakeRecord() (record enr.Record, err error) {
 	if r.identity == nil {
 		return record, errIdentityIsNil
 	}
-	record.Set(enr.IP(r.node.IP()))
+
+	ip := r.node.IP()
+	if srv != nil && (ip.IsLoopback() || IsPrivate(ip)) { // If AdvertiseAddr is not specified, 127.0.0.1 might be returned
+		ctx, cancel := context.WithTimeout(r.rootCtx, requestTimeout)
+		defer cancel()
+
+		ipAddr, err := r.client.RemoteIp(ctx, *srv)
+		if err != nil {
+			log.Error("could not obtain the external ip address", "err", err)
+		} else {
+			parsedIP := net.ParseIP(ipAddr)
+			if parsedIP != nil {
+				ip = parsedIP
+				log.Info("node's external IP address", "ipAddr", ipAddr)
+			} else {
+				log.Error("invalid ip address obtained from rendezvous server", "ipaddr", ipAddr, "err", err)
+			}
+		}
+	}
+
+	record.Set(enr.IP(ip))
 	record.Set(enr.TCP(r.node.TCP()))
 	record.Set(enr.UDP(r.node.UDP()))
 	// public key is added to ENR when ENR is signed
@@ -127,8 +147,7 @@ func (r *Rendezvous) MakeRecord() (record enr.Record, err error) {
 	return record, nil
 }
 
-func (r *Rendezvous) register(topic string, record enr.Record) error {
+func (r *Rendezvous) register(srv ma.Multiaddr, topic string, record enr.Record) error {
-	srv := r.servers[rand.Intn(len(r.servers))] // nolint: gosec
 	ctx, cancel := context.WithTimeout(r.rootCtx, requestTimeout)
 	defer cancel()
 
@@ -146,7 +165,8 @@ func (r *Rendezvous) register(topic string, record enr.Record) error {
 
 // Register renews registration in the specified server.
 func (r *Rendezvous) Register(topic string, stop chan struct{}) error {
-	record, err := r.MakeRecord()
+	srv := r.getRandomServer()
+	record, err := r.MakeRecord(&srv)
 	if err != nil {
 		return err
 	}
@@ -155,7 +175,7 @@ func (r *Rendezvous) Register(topic string, stop chan struct{}) error {
 	ticker := time.NewTicker(r.registrationPeriod / 2)
 	defer ticker.Stop()
 
-	if err := r.register(topic, record); err == context.Canceled {
+	if err := r.register(srv, topic, record); err == context.Canceled {
 		return err
 	}
 
@@ -164,7 +184,7 @@ func (r *Rendezvous) Register(topic string, stop chan struct{}) error {
 		case <-stop:
 			return nil
 		case <-ticker.C:
-			if err := r.register(topic, record); err == context.Canceled {
+			if err := r.register(r.getRandomServer(), topic, record); err == context.Canceled {
 				return err
 			} else if err == errDiscoveryIsStopped {
 				return nil
@@ -230,6 +250,10 @@ func (r *Rendezvous) Discover(
 	}
 }
 
+func (r *Rendezvous) getRandomServer() ma.Multiaddr {
+	return r.servers[rand.Intn(len(r.servers))] // nolint: gosec
+}
+
 func enrToNode(record enr.Record) (*discv5.Node, error) {
 	var (
 		key    enode.Secp256k1
@@ -253,3 +277,27 @@ func enrToNode(record enr.Record) (*discv5.Node, error) {
 	_ = record.Load(&uport)
 	return discv5.NewNode(nodeID, net.IP(ip), uint16(uport), uint16(tport)), nil
 }
+
+// IsPrivate reports whether ip is a private address, according to
+// RFC 1918 (IPv4 addresses) and RFC 4193 (IPv6 addresses).
+// Copied/Adapted from https://go-review.googlesource.com/c/go/+/272668/11/src/net/ip.go
+// Copyright (c) The Go Authors. All rights reserved.
+// @TODO: once Go 1.17 is released in Q42021, remove this function as it will become part of the language
+func IsPrivate(ip net.IP) bool {
+	if ip4 := ip.To4(); ip4 != nil {
+		// Following RFC 4193, Section 3. Local IPv6 Unicast Addresses which says:
+		//   The Internet Assigned Numbers Authority (IANA) has reserved the
+		//   following three blocks of the IPv4 address space for private internets:
+		//     10.0.0.0        -   10.255.255.255  (10/8 prefix)
+		//     172.16.0.0      -   172.31.255.255  (172.16/12 prefix)
+		//     192.168.0.0     -   192.168.255.255 (192.168/16 prefix)
+		return ip4[0] == 10 ||
+			(ip4[0] == 172 && ip4[1]&0xf0 == 16) ||
+			(ip4[0] == 192 && ip4[1] == 168)
+	}
+	// Following RFC 4193, Section 3. Private Address Space which says:
+	//   The Internet Assigned Numbers Authority (IANA) has reserved the
+	//   following block of the IPv6 address space for local internets:
+	//     FC00::  -  FDFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF (FC00::/7 prefix)
+	return len(ip) == net.IPv6len && ip[0]&0xfe == 0xfc
+}

discovery/rendezvous_test.go

@@ -68,7 +68,7 @@ func TestMakeRecordReturnsCachedRecord(t *testing.T) {
 	record := enr.Record{}
 	require.NoError(t, enode.SignV4(&record, identity))
 	c := NewRendezvousWithENR(nil, record)
-	rst, err := c.MakeRecord()
+	rst, err := c.MakeRecord(nil)
 	require.NoError(t, err)
 	require.NotNil(t, enode.V4ID{}.NodeAddr(&rst))
 	require.Equal(t, enode.V4ID{}.NodeAddr(&record), enode.V4ID{}.NodeAddr(&rst))
@@ -79,7 +79,7 @@ func TestRendezvousRegisterAndDiscoverExitGracefully(t *testing.T) {
 	require.NoError(t, err)
 	require.NoError(t, r.Start())
 	require.NoError(t, r.Stop())
-	require.EqualError(t, errDiscoveryIsStopped, r.register("", enr.Record{}).Error())
+	require.EqualError(t, errDiscoveryIsStopped, r.register(r.getRandomServer(), "", enr.Record{}).Error())
 	_, err = r.discoverRequest(nil, "")
 	require.EqualError(t, errDiscoveryIsStopped, err.Error())
 }

go.mod

@@ -51,7 +51,7 @@ require (
 	github.com/status-im/go-wakurelay-pubsub v0.4.3-0.20210729162817-adc68830282a
 	github.com/status-im/markdown v0.0.0-20201022101546-c0cbdd5763bf
 	github.com/status-im/migrate/v4 v4.6.2-status.2
-	github.com/status-im/rendezvous v1.3.2
+	github.com/status-im/rendezvous v1.3.1-0.20210824184947-7c79c858170c
 	github.com/status-im/status-go/extkeys v1.1.2
 	github.com/status-im/tcp-shaker v0.0.0-20191114194237-215893130501
 	github.com/stretchr/testify v1.7.0

go.sum

@@ -1113,8 +1113,8 @@ github.com/status-im/markdown v0.0.0-20201022101546-c0cbdd5763bf h1:0w1mjNUqEHoL
 github.com/status-im/markdown v0.0.0-20201022101546-c0cbdd5763bf/go.mod h1:9yR8woqkJIHs3sf9pEjYvaGfmhsXR1leEMAX6+Z5y+M=
 github.com/status-im/migrate/v4 v4.6.2-status.2 h1:SdC+sMDl/aI7vUlwD2qj2p7KsK4T60IS9z4/rYCCbI8=
 github.com/status-im/migrate/v4 v4.6.2-status.2/go.mod h1:c/kc90n47GZu/58nnz1OMLTf7uE4Da4gZP5qmU+A/v8=
-github.com/status-im/rendezvous v1.3.2 h1:eLTQ1EEg/qTsFDM6lwIf7tAFqiD3zEHnbWKaS3fvd/E=
+github.com/status-im/rendezvous v1.3.1-0.20210824184947-7c79c858170c h1:l83ciN0A5LW7c6NMa/j0x2mH1vsv3hbAAUTEwZw6qF4=
-github.com/status-im/rendezvous v1.3.2/go.mod h1:CK8B3kCbx3QrE0V64aAocU8oh9KRktoKSU0sqiF6MwI=
+github.com/status-im/rendezvous v1.3.1-0.20210824184947-7c79c858170c/go.mod h1:CK8B3kCbx3QrE0V64aAocU8oh9KRktoKSU0sqiF6MwI=
 github.com/status-im/resize v0.0.0-20201215164250-7c6d9f0d3088 h1:ClCAP2FPCvl8hGMhbUx/tq/sOu2wibztAa5jAvQEe4Q=
 github.com/status-im/resize v0.0.0-20201215164250-7c6d9f0d3088/go.mod h1:+92j1tN27DypDeBFxkg0uzkqfh1bNHTZe3Bv2PjvxpM=
 github.com/status-im/status-go/extkeys v1.1.2 h1:FSjARgDathJ3rIapJt851LsIXP9Oyuu2M2jPJKuzloU=

params/config.go

@@ -340,6 +340,9 @@ type NodeConfig struct {
 
 	// AdvertiseAddr is a public IP address the node wants to be found with.
 	// It is especially useful when using floating IPs attached to a server.
+	// This configuration value is used by rendezvous protocol, and it's optional
+	// If no value is specified, it will attempt to determine the node's external
+	// IP address. A value can be specified in case the returned address is incorrect
 	AdvertiseAddr string
 
 	// Name sets the instance name of the node. It must not contain the / character.

vendor/github.com/status-im/rendezvous/client.go

@@ -115,12 +115,46 @@ func (c Client) Discover(ctx context.Context, srv ma.Multiaddr, topic string, li
 	return val.Records, nil
 }
 
+func (c Client) RemoteIp(ctx context.Context, srv ma.Multiaddr) (value string, err error) {
+	s, err := c.newStream(ctx, srv)
+	if err != nil {
+		return
+	}
+	defer s.Close()
+
+	if err = rlp.Encode(s, protocol.REMOTEIP); err != nil {
+		return
+	}
+
+	rs := rlp.NewStream(s, 0)
+	typ, err := rs.Uint()
+	if err != nil {
+		return
+	}
+	if protocol.MessageType(typ) != protocol.REMOTEIP_RESPONSE {
+		err = fmt.Errorf("expected %v as response, but got %v", protocol.REMOTEIP_RESPONSE, typ)
+		return
+	}
+	var val protocol.RemoteIpResponse
+	if err = rs.Decode(&val); err != nil {
+		return
+	}
+	if val.Status != protocol.OK {
+		err = fmt.Errorf("remoteip request failed. status code %v", val.Status)
+		return
+	}
+	logger.Debug("received response to remoteip request", "status", val.Status, "ip", val.IP)
+	value = val.IP
+
+	return
+}
+
 func (c Client) newStream(ctx context.Context, srv ma.Multiaddr) (rw network.Stream, err error) {
 	pid, err := srv.ValueForProtocol(ethv4.P_ETHv4)
 	if err != nil {
 		return
 	}
-	peerid, err := peer.IDB58Decode(pid)
+	peerid, err := peer.Decode(pid)
 	if err != nil {
 		return
 	}

vendor/github.com/status-im/rendezvous/protocol/protocol.go

@@ -14,6 +14,8 @@ const (
 	REGISTER_RESPONSE
 	DISCOVER
 	DISCOVER_RESPONSE
+	REMOTEIP
+	REMOTEIP_RESPONSE
 
 	OK                  ResponseStatus = 0
 	E_INVALID_NAMESPACE ResponseStatus = 100
@@ -46,3 +48,11 @@ type DiscoverResponse struct {
 	Message string
 	Records []enr.Record
 }
+
+type RemoteIp struct {
+}
+
+type RemoteIpResponse struct {
+	Status ResponseStatus
+	IP     string
+}

vendor/github.com/status-im/rendezvous/server/server.go

@@ -16,6 +16,7 @@ import (
 	"github.com/libp2p/go-libp2p-core/crypto"
 	"github.com/libp2p/go-libp2p-core/host"
 	"github.com/libp2p/go-libp2p-core/network"
+	"github.com/multiformats/go-multiaddr"
 	ma "github.com/multiformats/go-multiaddr"
 	"github.com/status-im/rendezvous/protocol"
 )
@@ -132,7 +133,7 @@ func (srv *Server) startListener() error {
 				return
 			}
 			s.SetReadDeadline(time.Now().Add(srv.readTimeout))
-			resptype, resp, err := srv.msgParser(protocol.MessageType(typ), rs)
+			resptype, resp, err := srv.msgParser(s, protocol.MessageType(typ), rs)
 			if err == io.EOF {
 				return
 			}
@@ -198,7 +199,7 @@ type Decoder interface {
 	Decode(val interface{}) error
 }
 
-func (srv *Server) msgParser(typ protocol.MessageType, d Decoder) (resptype protocol.MessageType, resp interface{}, err error) {
+func (srv *Server) msgParser(s network.Stream, typ protocol.MessageType, d Decoder) (resptype protocol.MessageType, resp interface{}, err error) {
 	switch typ {
 	case protocol.REGISTER:
 		var msg protocol.Register
@@ -229,6 +230,14 @@ func (srv *Server) msgParser(typ protocol.MessageType, d Decoder) (resptype prot
 		metrics.ObserveDiscoveryDuration(time.Since(start).Seconds(), msg.Topic)
 		metrics.ObserveDiscoverSize(float64(len(records)), msg.Topic)
 		return resptype, protocol.DiscoverResponse{Status: protocol.OK, Records: records}, nil
+	case protocol.REMOTEIP:
+		resptype = protocol.REMOTEIP_RESPONSE
+		ip, err := s.Conn().RemoteMultiaddr().ValueForProtocol(multiaddr.P_IP4)
+		if err != nil {
+			metrics.CountError("remoteip")
+			return resptype, protocol.RemoteIpResponse{Status: protocol.E_INTERNAL_ERROR}, err
+		}
+		return resptype, protocol.RemoteIpResponse{Status: protocol.OK, IP: ip}, nil
 	default:
 		metrics.CountError("unknown")
 		// don't send the response

vendor/modules.txt

@@ -451,7 +451,7 @@ github.com/status-im/migrate/v4/database/postgres
 github.com/status-im/migrate/v4/database/sqlcipher
 github.com/status-im/migrate/v4/internal/url
 github.com/status-im/migrate/v4/source/go_bindata
-# github.com/status-im/rendezvous v1.3.2
+# github.com/status-im/rendezvous v1.3.1-0.20210824184947-7c79c858170c
 github.com/status-im/rendezvous
 github.com/status-im/rendezvous/protocol
 github.com/status-im/rendezvous/server