p2p/discover: New endpoint format

eth/backend.go

@@ -277,8 +277,8 @@ func (s *Ethereum) NodeInfo() *NodeInfo {
 		NodeUrl:    node.String(),
 		NodeID:     node.ID.String(),
 		IP:         node.IP.String(),
-		DiscPort:   node.DiscPort,
-		TCPPort:    node.TCPPort,
+		DiscPort:   int(node.UDP),
+		TCPPort:    int(node.TCP),
 		ListenAddr: s.net.ListenAddr,
 		Td:         s.ChainManager().Td().String(),
 	}

p2p/discover/database_test.go

@@ -6,6 +6,7 @@ import (
 	"net"
 	"os"
 	"path/filepath"
+	"reflect"
 	"testing"
 	"time"
 )
@@ -86,9 +87,10 @@ func TestNodeDBInt64(t *testing.T) {
 
 func TestNodeDBFetchStore(t *testing.T) {
 	node := &Node{
-		ID:      MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
-		IP:      net.IP([]byte{192, 168, 0, 1}),
-		TCPPort: 30303,
+		ID:  MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
+		IP:  net.IP([]byte{192, 168, 0, 1}),
+		UDP: 30303,
+		TCP: 30303,
 	}
 	inst := time.Now()
 
@@ -124,7 +126,7 @@ func TestNodeDBFetchStore(t *testing.T) {
 	}
 	if stored := db.node(node.ID); stored == nil {
 		t.Errorf("node: not found")
-	} else if !bytes.Equal(stored.ID[:], node.ID[:]) || !stored.IP.Equal(node.IP) || stored.TCPPort != node.TCPPort {
+	} else if !reflect.DeepEqual(stored, node) {
 		t.Errorf("node: data mismatch: have %v, want %v", stored, node)
 	}
 }

p2p/discover/node.go

@@ -6,7 +6,6 @@ import (
 	"encoding/hex"
 	"errors"
 	"fmt"
-	"io"
 	"math/big"
 	"math/rand"
 	"net"
@@ -16,49 +15,45 @@ import (
 
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/crypto/secp256k1"
-	"github.com/ethereum/go-ethereum/rlp"
 )
 
 const nodeIDBits = 512
 
 // Node represents a host on the network.
 type Node struct {
-	ID NodeID
-	IP net.IP
-
-	DiscPort int // UDP listening port for discovery protocol
-	TCPPort  int // TCP listening port for RLPx
+	IP       net.IP // len 4 for IPv4 or 16 for IPv6
+	UDP, TCP uint16 // port numbers
+	ID       NodeID
 }
 
 func newNode(id NodeID, addr *net.UDPAddr) *Node {
+	ip := addr.IP.To4()
+	if ip == nil {
+		ip = addr.IP.To16()
+	}
 	return &Node{
-		ID:       id,
-		IP:       addr.IP,
-		DiscPort: addr.Port,
-		TCPPort:  addr.Port,
+		IP:  ip,
+		UDP: uint16(addr.Port),
+		TCP: uint16(addr.Port),
+		ID:  id,
 	}
 }
 
-func (n *Node) isValid() bool {
-	// TODO: don't accept localhost, LAN addresses from internet hosts
-	return !n.IP.IsMulticast() && !n.IP.IsUnspecified() && n.TCPPort != 0 && n.DiscPort != 0
-}
-
 func (n *Node) addr() *net.UDPAddr {
-	return &net.UDPAddr{IP: n.IP, Port: n.DiscPort}
+	return &net.UDPAddr{IP: n.IP, Port: int(n.UDP)}
 }
 
 // The string representation of a Node is a URL.
 // Please see ParseNode for a description of the format.
 func (n *Node) String() string {
-	addr := net.TCPAddr{IP: n.IP, Port: n.TCPPort}
+	addr := net.TCPAddr{IP: n.IP, Port: int(n.TCP)}
 	u := url.URL{
 		Scheme: "enode",
 		User:   url.User(fmt.Sprintf("%x", n.ID[:])),
 		Host:   addr.String(),
 	}
-	if n.DiscPort != n.TCPPort {
-		u.RawQuery = "discport=" + strconv.Itoa(n.DiscPort)
+	if n.UDP != n.TCP {
+		u.RawQuery = "discport=" + strconv.Itoa(int(n.UDP))
 	}
 	return u.String()
 }
@@ -98,16 +93,20 @@ func ParseNode(rawurl string) (*Node, error) {
 	if n.IP = net.ParseIP(ip); n.IP == nil {
 		return nil, errors.New("invalid IP address")
 	}
-	if n.TCPPort, err = strconv.Atoi(port); err != nil {
+	tcp, err := strconv.ParseUint(port, 10, 16)
+	if err != nil {
 		return nil, errors.New("invalid port")
 	}
+	n.TCP = uint16(tcp)
 	qv := u.Query()
 	if qv.Get("discport") == "" {
-		n.DiscPort = n.TCPPort
+		n.UDP = n.TCP
 	} else {
-		if n.DiscPort, err = strconv.Atoi(qv.Get("discport")); err != nil {
+		udp, err := strconv.ParseUint(qv.Get("discport"), 10, 16)
+		if err != nil {
 			return nil, errors.New("invalid discport in query")
 		}
+		n.UDP = uint16(udp)
 	}
 	return &n, nil
 }
@@ -121,22 +120,6 @@ func MustParseNode(rawurl string) *Node {
 	return n
 }
 
-func (n Node) EncodeRLP(w io.Writer) error {
-	return rlp.Encode(w, rpcNode{IP: n.IP.String(), Port: uint16(n.TCPPort), ID: n.ID})
-}
-func (n *Node) DecodeRLP(s *rlp.Stream) (err error) {
-	var ext rpcNode
-	if err = s.Decode(&ext); err == nil {
-		n.TCPPort = int(ext.Port)
-		n.DiscPort = int(ext.Port)
-		n.ID = ext.ID
-		if n.IP = net.ParseIP(ext.IP); n.IP == nil {
-			return errors.New("invalid IP string")
-		}
-	}
-	return err
-}
-
 // NodeID is a unique identifier for each node.
 // The node identifier is a marshaled elliptic curve public key.
 type NodeID [nodeIDBits / 8]byte

p2p/discover/node_test.go

@@ -49,28 +49,28 @@ var parseNodeTests = []struct {
 	{
 		rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:52150",
 		wantResult: &Node{
-			ID:       MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
-			IP:       net.ParseIP("127.0.0.1"),
-			DiscPort: 52150,
-			TCPPort:  52150,
+			ID:  MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
+			IP:  net.ParseIP("127.0.0.1"),
+			UDP: 52150,
+			TCP: 52150,
 		},
 	},
 	{
 		rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@[::]:52150",
 		wantResult: &Node{
-			ID:       MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
-			IP:       net.ParseIP("::"),
-			DiscPort: 52150,
-			TCPPort:  52150,
+			ID:  MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
+			IP:  net.ParseIP("::"),
+			UDP: 52150,
+			TCP: 52150,
 		},
 	},
 	{
-		rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:52150?discport=223344",
+		rawurl: "enode://1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439@127.0.0.1:52150?discport=22334",
 		wantResult: &Node{
-			ID:       MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
-			IP:       net.ParseIP("127.0.0.1"),
-			DiscPort: 223344,
-			TCPPort:  52150,
+			ID:  MustHexID("0x1dd9d65c4552b5eb43d5ad55a2ee3f56c6cbc1c64a5c8d659f51fcd51bace24351232b8d7821617d2b29b54b81cdefb9b3e9c37d7fd5f63270bcc9e1a6f6a439"),
+			IP:  net.ParseIP("127.0.0.1"),
+			UDP: 22334,
+			TCP: 52150,
 		},
 	},
 }

p2p/discover/table.go

@@ -220,7 +220,7 @@ func (tab *Table) bondall(nodes []*Node) (result []*Node) {
 	rc := make(chan *Node, len(nodes))
 	for i := range nodes {
 		go func(n *Node) {
-			nn, _ := tab.bond(false, n.ID, n.addr(), uint16(n.TCPPort))
+			nn, _ := tab.bond(false, n.ID, n.addr(), uint16(n.TCP))
 			rc <- nn
 		}(nodes[i])
 	}
@@ -299,12 +299,7 @@ func (tab *Table) pingpong(w *bondproc, pinged bool, id NodeID, addr *net.UDPAdd
 		tab.net.waitping(id)
 	}
 	// Bonding succeeded, update the node database
-	w.n = &Node{
-		ID:       id,
-		IP:       addr.IP,
-		DiscPort: addr.Port,
-		TCPPort:  int(tcpPort),
-	}
+	w.n = &Node{ID: id, IP: addr.IP, UDP: uint16(addr.Port), TCP: tcpPort}
 	tab.db.updateNode(w.n)
 	close(w.done)
 }

p2p/discover/table_test.go

@@ -261,9 +261,9 @@ func (t findnodeOracle) findnode(toid NodeID, toaddr *net.UDPAddr, target NodeID
 		panic("query to node at distance 0")
 	default:
 		// TODO: add more randomness to distances
-		next := toaddr.Port - 1
+		next := uint16(toaddr.Port) - 1
 		for i := 0; i < bucketSize; i++ {
-			result = append(result, &Node{ID: randomID(t.target, next), DiscPort: next})
+			result = append(result, &Node{ID: randomID(t.target, int(next)), UDP: next})
 		}
 	}
 	return result, nil

p2p/discover/udp.go

@@ -15,7 +15,7 @@ import (
 	"github.com/ethereum/go-ethereum/rlp"
 )
 
-const Version = 3
+const Version = 4
 
 // Errors
 var (
@@ -49,16 +49,20 @@ const (
 // RPC request structures
 type (
 	ping struct {
-		Version    uint   // must match Version
-		IP         string // our IP
-		Port       uint16 // our port
+		Version    uint
+		From, To   rpcEndpoint
 		Expiration uint64
 	}
 
-	// reply to Ping
+	// pong is the reply to ping.
 	pong struct {
-		ReplyTok   []byte
-		Expiration uint64
+		// This field should mirror the UDP envelope address
+		// of the ping packet, which provides a way to discover the
+		// the external address (after NAT).
+		To rpcEndpoint
+
+		ReplyTok   []byte // This contains the hash of the ping packet.
+		Expiration uint64 // Absolute timestamp at which the packet becomes invalid.
 	}
 
 	findnode struct {
@@ -73,12 +77,25 @@ type (
 		Nodes      []*Node
 		Expiration uint64
 	}
+
+	rpcEndpoint struct {
+		IP  net.IP // len 4 for IPv4 or 16 for IPv6
+		UDP uint16 // for discovery protocol
+		TCP uint16 // for RLPx protocol
+	}
 )
 
-type rpcNode struct {
-	IP   string
-	Port uint16
-	ID   NodeID
+func makeEndpoint(addr *net.UDPAddr, tcpPort uint16) rpcEndpoint {
+	ip := addr.IP.To4()
+	if ip == nil {
+		ip = addr.IP.To16()
+	}
+	return rpcEndpoint{IP: ip, UDP: uint16(addr.Port), TCP: tcpPort}
+}
+
+func validNode(n *Node) bool {
+	// TODO: don't accept localhost, LAN addresses from internet hosts
+	return !n.IP.IsMulticast() && !n.IP.IsUnspecified() && n.UDP != 0
 }
 
 type packet interface {
@@ -94,8 +111,9 @@ type conn interface {
 
 // udp implements the RPC protocol.
 type udp struct {
-	conn conn
-	priv *ecdsa.PrivateKey
+	conn        conn
+	priv        *ecdsa.PrivateKey
+	ourEndpoint rpcEndpoint
 
 	addpending chan *pending
 	gotreply   chan reply
@@ -176,6 +194,8 @@ func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath strin
 			realaddr = &net.UDPAddr{IP: ext, Port: realaddr.Port}
 		}
 	}
+	// TODO: separate TCP port
+	udp.ourEndpoint = makeEndpoint(realaddr, uint16(realaddr.Port))
 	udp.Table = newTable(udp, PubkeyID(&priv.PublicKey), realaddr, nodeDBPath)
 	go udp.loop()
 	go udp.readLoop()
@@ -194,8 +214,8 @@ func (t *udp) ping(toid NodeID, toaddr *net.UDPAddr) error {
 	errc := t.pending(toid, pongPacket, func(interface{}) bool { return true })
 	t.send(toaddr, pingPacket, ping{
 		Version:    Version,
-		IP:         t.self.IP.String(),
-		Port:       uint16(t.self.TCPPort),
+		From:       t.ourEndpoint,
+		To:         makeEndpoint(toaddr, 0), // TODO: maybe use known TCP port from DB
 		Expiration: uint64(time.Now().Add(expiration).Unix()),
 	})
 	return <-errc
@@ -214,7 +234,7 @@ func (t *udp) findnode(toid NodeID, toaddr *net.UDPAddr, target NodeID) ([]*Node
 		reply := r.(*neighbors)
 		for _, n := range reply.Nodes {
 			nreceived++
-			if n.isValid() {
+			if validNode(n) {
 				nodes = append(nodes, n)
 			}
 		}
@@ -374,17 +394,22 @@ func (t *udp) readLoop() {
 		if err != nil {
 			return
 		}
-		packet, fromID, hash, err := decodePacket(buf[:nbytes])
-		if err != nil {
-			glog.V(logger.Debug).Infof("Bad packet from %v: %v\n", from, err)
-			continue
-		}
-		status := "ok"
-		if err := packet.handle(t, from, fromID, hash); err != nil {
-			status = err.Error()
-		}
-		glog.V(logger.Detail).Infof("<<< %v %T: %s\n", from, packet, status)
+		t.handlePacket(from, buf[:nbytes])
+	}
+}
+
+func (t *udp) handlePacket(from *net.UDPAddr, buf []byte) error {
+	packet, fromID, hash, err := decodePacket(buf)
+	if err != nil {
+		glog.V(logger.Debug).Infof("Bad packet from %v: %v\n", from, err)
+		return err
 	}
+	status := "ok"
+	if err = packet.handle(t, from, fromID, hash); err != nil {
+		status = err.Error()
+	}
+	glog.V(logger.Detail).Infof("<<< %v %T: %s\n", from, packet, status)
+	return err
 }
 
 func decodePacket(buf []byte) (packet, NodeID, []byte, error) {
@@ -425,12 +450,13 @@ func (req *ping) handle(t *udp, from *net.UDPAddr, fromID NodeID, mac []byte) er
 		return errBadVersion
 	}
 	t.send(from, pongPacket, pong{
+		To:         makeEndpoint(from, req.From.TCP),
 		ReplyTok:   mac,
 		Expiration: uint64(time.Now().Add(expiration).Unix()),
 	})
 	if !t.handleReply(fromID, pingPacket, req) {
 		// Note: we're ignoring the provided IP address right now
-		go t.bond(true, fromID, from, req.Port)
+		go t.bond(true, fromID, from, req.From.TCP)
 	}
 	return nil
 }