wip

node/cipher-data.go

@@ -0,0 +1,61 @@
+package node
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+)
+
+type dataCipher struct {
+	key  []byte
+	aead cipher.AEAD
+}
+
+func newDataCipher() *dataCipher {
+	key := make([]byte, 32)
+	if _, err := rand.Read(key); err != nil {
+		panic(err)
+	}
+	return newDataCipherFromKey(key)
+}
+
+// key must be 32 bytes.
+func newDataCipherFromKey(key []byte) *dataCipher {
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		panic(err)
+	}
+
+	aead, err := cipher.NewGCM(block)
+	if err != nil {
+		panic(err)
+	}
+
+	return &dataCipher{key: key, aead: aead}
+}
+
+func (sc *dataCipher) Key() []byte {
+	return sc.key
+}
+
+func (sc *dataCipher) Encrypt(h xHeader, data, out []byte) []byte {
+	const s = dataHeaderSize
+	out = out[:s+dataCipherOverhead+len(data)]
+	h.Marshal(dataStreamID, out[:s])
+	sc.aead.Seal(out[s:s], out[:s], data, nil)
+	return out
+}
+
+func (sc *dataCipher) Decrypt(encrypted, out []byte) (data []byte, ok bool) {
+	const s = dataHeaderSize
+	if len(encrypted) < s+dataCipherOverhead {
+		ok = false
+		return
+	}
+
+	var err error
+
+	data, err = sc.aead.Open(out[:0], encrypted[:s], encrypted[s:], nil)
+	ok = err == nil
+	return
+}

node/cipher-data_test.go

@@ -22,7 +22,7 @@ func TestDataCipher(t *testing.T) {
 	}
 
 	for _, plaintext := range testCases {
-		h1 := dataHeader{
+		h1 := xHeader{
 			Counter:  235153,
 			SourceIP: 4,
 			DestIP:   88,
@@ -31,11 +31,13 @@ func TestDataCipher(t *testing.T) {
 		encrypted := make([]byte, bufferSize)
 
 		dc1 := newDataCipher()
-		encrypted = dc1.Encrypt(&h1, plaintext, encrypted)
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
+		h2 := xHeader{}
+		h2.Parse(encrypted)
 
 		dc2 := newDataCipherFromKey(dc1.Key())
 
-		decrypted, h2, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
+		decrypted, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
 		if !ok {
 			t.Fatal(ok)
 		}
@@ -64,7 +66,7 @@ func TestDataCipher_ModifyCiphertext(t *testing.T) {
 	}
 
 	for _, plaintext := range testCases {
-		h1 := dataHeader{
+		h1 := xHeader{
 			Counter:  235153,
 			SourceIP: 4,
 			DestIP:   88,
@@ -73,14 +75,14 @@ func TestDataCipher_ModifyCiphertext(t *testing.T) {
 		encrypted := make([]byte, bufferSize)
 
 		dc1 := newDataCipher()
-		encrypted = dc1.Encrypt(&h1, plaintext, encrypted)
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
 		encrypted[mrand.IntN(len(encrypted))]++
 
 		dc2 := newDataCipherFromKey(dc1.Key())
 
-		_, h2, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
+		_, ok := dc2.Decrypt(encrypted, make([]byte, bufferSize-dataHeaderSize))
 		if ok {
-			t.Fatal(ok, h2)
+			t.Fatal(ok)
 		}
 	}
 }
@@ -89,14 +91,14 @@ func TestDataCipher_ShortCiphertext(t *testing.T) {
 	dc1 := newDataCipher()
 	shortText := make([]byte, dataHeaderSize+dataCipherOverhead-1)
 	rand.Read(shortText)
-	_, _, ok := dc1.Decrypt(shortText, make([]byte, bufferSize))
+	_, ok := dc1.Decrypt(shortText, make([]byte, bufferSize))
 	if ok {
 		t.Fatal(ok)
 	}
 }
 
 func BenchmarkDataCipher_Encrypt(b *testing.B) {
-	h1 := dataHeader{
+	h1 := xHeader{
 		Counter:  235153,
 		SourceIP: 4,
 		DestIP:   88,
@@ -110,12 +112,12 @@ func BenchmarkDataCipher_Encrypt(b *testing.B) {
 	dc1 := newDataCipher()
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		encrypted = dc1.Encrypt(&h1, plaintext, encrypted)
+		encrypted = dc1.Encrypt(h1, plaintext, encrypted)
 	}
 }
 
 func BenchmarkDataCipher_Decrypt(b *testing.B) {
-	h1 := dataHeader{
+	h1 := xHeader{
 		Counter:  235153,
 		SourceIP: 4,
 		DestIP:   88,
@@ -127,12 +129,12 @@ func BenchmarkDataCipher_Decrypt(b *testing.B) {
 	encrypted := make([]byte, bufferSize)
 
 	dc1 := newDataCipher()
-	encrypted = dc1.Encrypt(&h1, plaintext, encrypted)
+	encrypted = dc1.Encrypt(h1, plaintext, encrypted)
 
 	decrypted := make([]byte, bufferSize)
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		decrypted, _, _ = dc1.Decrypt(encrypted, decrypted)
+		decrypted, _ = dc1.Decrypt(encrypted, decrypted)
 	}
 }

node/cipher-routing.go

@@ -0,0 +1,26 @@
+package node
+
+import "golang.org/x/crypto/nacl/box"
+
+type routingCipher struct {
+	sharedKey [32]byte
+}
+
+func newRoutingCipher(privKey, pubKey []byte) routingCipher {
+	shared := [32]byte{}
+	box.Precompute(&shared, (*[32]byte)(pubKey), (*[32]byte)(privKey))
+	return routingCipher{shared}
+}
+
+func (rc routingCipher) Encrypt(h xHeader, data, out []byte) []byte {
+	const s = routingHeaderSize
+	out = out[:s+routingCipherOverhead+len(data)]
+	h.Marshal(routingStreamID, out[:s])
+	box.SealAfterPrecomputation(out[s:s], data, (*[24]byte)(out[:s]), &rc.sharedKey)
+	return out
+}
+
+func (rc routingCipher) Decrypt(encrypted, out []byte) (data []byte, ok bool) {
+	const s = routingHeaderSize
+	return box.OpenAfterPrecomputation(out[:0], encrypted[s:], (*[24]byte)(encrypted[:s]), &rc.sharedKey)
+}

node/cipher-routing_test.go

@@ -0,0 +1,114 @@
+package node
+
+import (
+	"bytes"
+	"crypto/rand"
+	"testing"
+
+	"golang.org/x/crypto/nacl/box"
+)
+
+func newRoutingCipherForTesting() (c1, c2 routingCipher) {
+	pubKey1, privKey1, err := box.GenerateKey(rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	pubKey2, privKey2, err := box.GenerateKey(rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	return newRoutingCipher(privKey1[:], pubKey2[:]),
+		newRoutingCipher(privKey2[:], pubKey1[:])
+}
+
+func TestRoutingCipher(t *testing.T) {
+	c1, c2 := newRoutingCipherForTesting()
+
+	maxSizePlaintext := make([]byte, bufferSize-routingHeaderSize-routingCipherOverhead)
+	rand.Read(maxSizePlaintext)
+
+	testCases := [][]byte{
+		make([]byte, 0),
+		{1},
+		{255},
+		{1, 2, 3, 4, 5},
+		[]byte("Hello world"),
+		maxSizePlaintext,
+	}
+
+	for _, plaintext := range testCases {
+		h1 := xHeader{
+			Counter:  235153,
+			SourceIP: 4,
+			DestIP:   88,
+		}
+
+		encrypted := make([]byte, bufferSize)
+
+		encrypted = c1.Encrypt(h1, plaintext, encrypted)
+
+		decrypted, ok := c2.Decrypt(encrypted, make([]byte, bufferSize))
+		if !ok {
+			t.Fatal(ok)
+		}
+
+		if !bytes.Equal(decrypted, plaintext) {
+			t.Fatal("not equal")
+		}
+	}
+}
+
+func TestRoutingCipher_ShortCiphertext(t *testing.T) {
+	c1, _ := newRoutingCipherForTesting()
+	shortText := make([]byte, routingHeaderSize+routingCipherOverhead-1)
+	rand.Read(shortText)
+	_, ok := c1.Decrypt(shortText, make([]byte, bufferSize))
+	if ok {
+		t.Fatal(ok)
+	}
+}
+
+func BenchmarkRoutingCipher_Encrypt(b *testing.B) {
+	c1, _ := newRoutingCipherForTesting()
+	h1 := xHeader{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-routingHeaderSize-routingCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		encrypted = c1.Encrypt(h1, plaintext, encrypted)
+	}
+}
+
+func BenchmarkRoutingCipher_Decrypt(b *testing.B) {
+	c1, c2 := newRoutingCipherForTesting()
+
+	h1 := xHeader{
+		Counter:  235153,
+		SourceIP: 4,
+		DestIP:   88,
+	}
+
+	plaintext := make([]byte, bufferSize-routingHeaderSize-routingCipherOverhead)
+	rand.Read(plaintext)
+
+	encrypted := make([]byte, bufferSize)
+
+	encrypted = c1.Encrypt(h1, plaintext, encrypted)
+
+	decrypted := make([]byte, bufferSize)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		decrypted, _ = c2.Decrypt(encrypted, decrypted)
+	}
+}

node/cipher.go

@@ -0,0 +1,6 @@
+package node
+
+type packetCipher interface {
+	Encrypt(h xHeader, data, out []byte) []byte
+	Decrypt(encrypted, out []byte) (data []byte, ok bool)
+}

node/conn.go

@@ -35,6 +35,33 @@ func newConnWriter(conn *net.UDPConn, localIP byte, routing *routingTable) *conn
 	return w
 }
 
+/*
+	func (w *connWriter) SendRouting(remoteIP byte, data []byte) {
+		dstPeer := w.routing.Get(remoteIP)
+		if dstPeer == nil {
+			log.Printf("No peer: %d", remoteIP)
+			return
+		}
+
+		var viaPeer *peer
+
+		if dstPeer.Addr == zeroAddrPort {
+			viaPeer = w.routing.Mediator()
+			if viaPeer == nil {
+				log.Printf("No mediator: %d", remoteIP)
+				return
+			}
+		}
+
+		w.sendRouting(dstPeer, viaPeer, data)
+	}
+*/
+
+func (w *connWriter) SendData(remoteIP byte, data []byte) {
+	// TODO
+}
+
+// TODO: deprecated
 func (w *connWriter) WriteTo(remoteIP, stream byte, data []byte) {
 	dstPeer := w.routing.Get(remoteIP)
 	if dstPeer == nil {
@@ -50,11 +77,11 @@ func (w *connWriter) WriteTo(remoteIP, stream byte, data []byte) {
 	var viaPeer *peer
 	if dstPeer.Mediated {
 		viaPeer = w.routing.mediator.Load()
-		if viaPeer == nil || viaPeer.Addr == nil {
+		if viaPeer == nil || viaPeer.Addr == zeroAddrPort {
 			log.Printf("Mediator not connected")
 			return
 		}
-	} else if dstPeer.Addr == nil {
+	} else if dstPeer.Addr == zeroAddrPort {
 		log.Printf("Peer doesn't have address: %d", remoteIP)
 		return
 	}
@@ -62,6 +89,7 @@ func (w *connWriter) WriteTo(remoteIP, stream byte, data []byte) {
 	w.WriteToPeer(dstPeer, viaPeer, stream, data)
 }
 
+// TODO: deprecated
 func (w *connWriter) WriteToPeer(dstPeer, viaPeer *peer, stream byte, data []byte) {
 	w.lock.Lock()
 
@@ -89,20 +117,21 @@ func (w *connWriter) WriteToPeer(dstPeer, viaPeer *peer, stream byte, data []byt
 		addr = viaPeer.Addr
 	}
 
-	if _, err := w.WriteToUDPAddrPort(buf, *addr); err != nil {
+	if _, err := w.WriteToUDPAddrPort(buf, addr); err != nil {
 		log.Fatalf("Failed to write to UDP port: %v", err)
 	}
 	w.lock.Unlock()
 }
 
+// TODO: deprecated
 func (w *connWriter) Forward(dstIP byte, packet []byte) {
 	dstPeer := w.routing.Get(dstIP)
-	if dstPeer == nil || dstPeer.Addr == nil {
+	if dstPeer == nil || dstPeer.Addr == zeroAddrPort {
 		log.Printf("No peer: %d", dstIP)
 		return
 	}
 
-	if _, err := w.WriteToUDPAddrPort(packet, *dstPeer.Addr); err != nil {
+	if _, err := w.WriteToUDPAddrPort(packet, dstPeer.Addr); err != nil {
 		log.Fatalf("Failed to write to UDP port: %v", err)
 	}
 }

node/datacipher.go

@@ -1,97 +0,0 @@
-package node
-
-import (
-	"crypto/aes"
-	"crypto/cipher"
-	"crypto/rand"
-	"unsafe"
-)
-
-// ----------------------------------------------------------------------------
-
-const (
-	dataStreamID       = 1
-	dataHeaderSize     = 12
-	dataCipherOverhead = 16 + 1
-)
-
-type dataHeader struct {
-	Counter  uint64 // Init with fasttime.Now() << 30 to ensure monotonic.
-	SourceIP byte
-	DestIP   byte
-}
-
-func (h *dataHeader) Parse(b []byte) {
-	h.Counter = *(*uint64)(unsafe.Pointer(&b[0]))
-	h.SourceIP = b[8]
-	h.DestIP = b[9]
-}
-
-func (h *dataHeader) Marshal(buf []byte) {
-	*(*uint64)(unsafe.Pointer(&buf[0])) = h.Counter
-	buf[8] = h.SourceIP
-	buf[9] = h.DestIP
-	buf[10] = 0
-	buf[11] = 0
-}
-
-// ----------------------------------------------------------------------------
-
-type dataCipher struct {
-	key  []byte
-	aead cipher.AEAD
-}
-
-func newDataCipher() *dataCipher {
-	key := make([]byte, 32)
-	if _, err := rand.Read(key); err != nil {
-		panic(err)
-	}
-	return newDataCipherFromKey(key)
-}
-
-// key must be 32 bytes.
-func newDataCipherFromKey(key []byte) *dataCipher {
-	block, err := aes.NewCipher(key)
-	if err != nil {
-		panic(err)
-	}
-
-	aead, err := cipher.NewGCM(block)
-	if err != nil {
-		panic(err)
-	}
-
-	return &dataCipher{key: key, aead: aead}
-}
-
-func (sc *dataCipher) Key() []byte {
-	return sc.key
-}
-
-func (sc *dataCipher) Encrypt(h *dataHeader, data, out []byte) []byte {
-	out = out[:dataHeaderSize+dataCipherOverhead+len(data)]
-	out[0] = dataStreamID
-
-	h.Marshal(out[1:])
-
-	const s = dataHeaderSize
-	sc.aead.Seal(out[1+s:1+s], out[1:1+s], data, nil)
-	return out
-}
-
-func (sc *dataCipher) Decrypt(encrypted, out []byte) (data []byte, h dataHeader, ok bool) {
-	const s = dataHeaderSize
-	if len(encrypted) < s+dataCipherOverhead {
-		ok = false
-		return
-	}
-
-	h.Parse(encrypted[1 : 1+s])
-
-	var err error
-
-	data, err = sc.aead.Open(out[:0], encrypted[1:1+s], encrypted[1+s:], nil)
-	ok = err == nil
-	return
-}

node/header.go

@@ -2,6 +2,41 @@ package node
 
 import "unsafe"
 
+// ----------------------------------------------------------------------------
+
+const (
+	routingStreamID       = 2
+	routingHeaderSize     = 24
+	routingCipherOverhead = 16
+
+	dataStreamID       = 1
+	dataHeaderSize     = 12
+	dataCipherOverhead = 16
+)
+
+// TODO: Rename
+type xHeader struct {
+	Counter  uint64 // Init with fasttime.Now() << 30 to ensure monotonic.
+	SourceIP byte
+	DestIP   byte
+}
+
+func (h *xHeader) Parse(b []byte) {
+	h.Counter = *(*uint64)(unsafe.Pointer(&b[1]))
+	h.SourceIP = b[9]
+	h.DestIP = b[10]
+}
+
+func (h *xHeader) Marshal(streamID byte, buf []byte) {
+	buf[0] = streamID
+	*(*uint64)(unsafe.Pointer(&buf[1])) = h.Counter
+	buf[9] = h.SourceIP
+	buf[10] = h.DestIP
+	buf[11] = 0
+}
+
+// ----------------------------------------------------------------------------
+// TODO: Remove this code.
 const (
 	headerSize    = 24
 	streamData    = 1

node/packets.go

@@ -0,0 +1,89 @@
+package node
+
+import (
+	"errors"
+	"net/netip"
+	"time"
+	"unsafe"
+)
+
+var errMalformedPacket = errors.New("malformed packet")
+
+const (
+	packetTypePing = iota + 1
+	packetTypePong
+)
+
+// ----------------------------------------------------------------------------
+
+type packetWrapper struct {
+	SrcIP      byte
+	RemoteAddr netip.AddrPort
+	Packet     any
+}
+
+// ----------------------------------------------------------------------------
+
+// A pingPacket is sent from a node acting as a client, to a node acting
+// as a server. It always contains the shared key the client is expecting
+// to use for data encryption with the server.
+type pingPacket struct {
+	SentAt    int64 // UnixMilli.
+	SharedKey [32]byte
+}
+
+func newPingPacket(sharedKey []byte) (pp pingPacket) {
+	pp.SentAt = time.Now().UnixMilli()
+	copy(pp.SharedKey[:], sharedKey)
+	return
+}
+
+func (p pingPacket) Marshal(buf []byte) []byte {
+	buf = buf[:41]
+	buf[0] = packetTypePing
+	*(*uint64)(unsafe.Pointer(&buf[1])) = uint64(p.SentAt)
+	copy(buf[9:41], p.SharedKey[:])
+	return buf
+}
+
+func (p *pingPacket) Parse(buf []byte) error {
+	if len(buf) != 41 {
+		return errMalformedPacket
+	}
+	p.SentAt = *(*int64)(unsafe.Pointer(&buf[1]))
+	copy(p.SharedKey[:], buf[9:41])
+	return nil
+}
+
+// ----------------------------------------------------------------------------
+
+// A pongPacket is sent by a node in a server role in response to a pingPacket.
+type pongPacket struct {
+	SentAt  int64 // UnixMilli.
+	RecvdAt int64 // UnixMilli.
+}
+
+func newPongPacket(sentAt int64) (pp pongPacket) {
+	pp.SentAt = sentAt
+	pp.RecvdAt = time.Now().UnixMilli()
+	return
+}
+
+func (p pongPacket) Marshal(buf []byte) []byte {
+	buf = buf[:17]
+	buf[0] = packetTypePong
+	*(*uint64)(unsafe.Pointer(&buf[1])) = uint64(p.SentAt)
+	*(*uint64)(unsafe.Pointer(&buf[9])) = uint64(p.RecvdAt)
+
+	return buf
+}
+
+func (p *pongPacket) Parse(buf []byte) error {
+	if len(buf) != 17 {
+		return errMalformedPacket
+	}
+	p.SentAt = *(*int64)(unsafe.Pointer(&buf[1]))
+	p.RecvdAt = *(*int64)(unsafe.Pointer(&buf[9]))
+
+	return nil
+}

node/packets_test.go

@@ -0,0 +1,42 @@
+package node
+
+import (
+	"crypto/rand"
+	"reflect"
+	"testing"
+)
+
+func TestPacketPing(t *testing.T) {
+	sharedKey := make([]byte, 32)
+	rand.Read(sharedKey)
+
+	buf := make([]byte, bufferSize)
+
+	p := newPingPacket(sharedKey)
+	out := p.Marshal(buf)
+
+	p2 := pingPacket{}
+	if err := p2.Parse(out); err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p, p2)
+	}
+}
+
+func TestPacketPong(t *testing.T) {
+	buf := make([]byte, bufferSize)
+
+	p := newPongPacket(123566)
+	out := p.Marshal(buf)
+
+	p2 := pongPacket{}
+	if err := p2.Parse(out); err != nil {
+		t.Fatal(err)
+	}
+
+	if !reflect.DeepEqual(p, p2) {
+		t.Fatal(p, p2)
+	}
+}

node/peersupervisor.go

@@ -36,7 +36,7 @@ type peerSupervisor struct {
 	// Peer-related items.
 	version        int64 // Ony accessed in HandlePeerUpdate.
 	peer           *m.Peer
-	remoteAddrPort *netip.AddrPort
+	remoteAddrPort netip.AddrPort
 	mediated       bool
 	sharedKey      []byte
 
@@ -123,9 +123,9 @@ func (s *peerSupervisor) stateInit() stateFunc {
 	addr, ok := netip.AddrFromSlice(s.peer.PublicIP)
 	if ok {
 		addrPort := netip.AddrPortFrom(addr, s.peer.Port)
-		s.remoteAddrPort = &addrPort
+		s.remoteAddrPort = addrPort
 	} else {
-		s.remoteAddrPort = nil
+		s.remoteAddrPort = zeroAddrPort
 	}
 	s.sharedKey = computeSharedKey(s.peer.EncPubKey, s.privKey)
 
@@ -153,7 +153,7 @@ func (s *peerSupervisor) stateSelectRole() stateFunc {
 	s.logf("STATE: SelectRole")
 	s.updateRoutingTable(false)
 
-	if s.remoteAddrPort != nil {
+	if s.remoteAddrPort != zeroAddrPort {
 		s.mediated = false
 
 		// If both remote and local are public, one side acts as client, and one
@@ -186,7 +186,7 @@ func (s *peerSupervisor) stateAccept() stateFunc {
 			switch pkt.Type {
 
 			case packetTypePing:
-				s.remoteAddrPort = &pkt.Addr
+				s.remoteAddrPort = pkt.Addr
 				s.updateRoutingTable(true)
 				s.sendPong(pkt.TraceID)
 				return s.stateConnected
@@ -256,8 +256,8 @@ func (s *peerSupervisor) stateConnected() stateFunc {
 
 				// Server should always follow remote port.
 				if s.localPublic {
-					if pkt.Addr != *s.remoteAddrPort {
+					if pkt.Addr != s.remoteAddrPort {
-						s.remoteAddrPort = &pkt.Addr
+						s.remoteAddrPort = pkt.Addr
 						s.updateRoutingTable(true)
 					}
 				}

node/router.go

@@ -12,12 +12,18 @@ import (
 	"vppn/m"
 )
 
+var zeroAddrPort = netip.AddrPort{}
+
 type peer struct {
-	Up        bool // No data will be sent to peers that are down.
+	IP            byte           // The VPN IP.
-	Mediator  bool
+	Up            bool           // No data will be sent to peers that are down.
+	Addr          netip.AddrPort // If we have direct connection, otherwise use mediator.
+	Mediator      bool           // True if the peer will mediate.
+	RoutingCipher routingCipher
+	DataCipher    dataCipher
+
+	// TODO: Deprecated below.
 	Mediated  bool
-	IP        byte
-	Addr      *netip.AddrPort // If we have direct connection, otherwise use mediator.
 	SharedKey []byte
 }
 
@@ -48,6 +54,10 @@ func (r *routingTable) Set(ip byte, p *peer) {
 	r.table[ip].Store(p)
 }
 
+func (r *routingTable) Mediator() *peer {
+	return r.mediator.Load()
+}
+
 // ----------------------------------------------------------------------------
 
 type router struct {

node/routingpacket.go

@@ -1,18 +1,9 @@
 package node
 
 import (
-	"errors"
 	"unsafe"
 )
 
-var errMalformedPacket = errors.New("malformed packet")
-
-const (
-	// Used to maintain connection.
-	packetTypePing = iota + 1
-	packetTypePong
-)
-
 type routingPacket struct {
 	Type    byte   // One of the packetType* constants.
 	TraceID uint64 // For matching requests and responses.