Moved endpoint into interface and simplified peer

src/conn.go

@@ -7,26 +7,28 @@ import (
 	"net"
 )
 
-type UDPBind interface {
+/* A Bind handles listening on a port for both IPv6 and IPv4 UDP traffic
+ */
+type Bind interface {
 	SetMark(value uint32) error
-	ReceiveIPv6(buff []byte, end *Endpoint) (int, error)
+	ReceiveIPv6(buff []byte) (int, Endpoint, error)
-	ReceiveIPv4(buff []byte, end *Endpoint) (int, error)
+	ReceiveIPv4(buff []byte) (int, Endpoint, error)
-	Send(buff []byte, end *Endpoint) error
+	Send(buff []byte, end Endpoint) error
 	Close() error
 }
 
 /* An Endpoint maintains the source/destination caching for a peer
  *
- * dst : the remote address of a peer
+ * dst : the remote address of a peer ("endpoint" in uapi terminology)
  * src : the local address from which datagrams originate going to the peer
- *
  */
-type UDPEndpoint interface {
+type Endpoint interface {
 	ClearSrc()           // clears the source address
 	ClearDst()           // clears the destination address
 	SrcToString() string // returns the local source address (ip:port)
 	DstToString() string // returns the destination address (ip:port)
 	DstToBytes() []byte  // used for mac2 cookie calculations
+	SetDst(string) error // used for manually setting the endpoint (uapi)
 	DstIP() net.IP
 	SrcIP() net.IP
 }
@@ -107,7 +109,9 @@ func UpdateUDPListener(device *Device) error {
 
 		for _, peer := range device.peers {
 			peer.mutex.Lock()
-			peer.endpoint.value.ClearSrc()
+			if peer.endpoint != nil {
+				peer.endpoint.ClearSrc()
+			}
 			peer.mutex.Unlock()
 		}
 

src/conn_linux.go

@@ -21,22 +21,24 @@ import (
  * See e.g. https://github.com/golang/go/issues/17930
  * So this code is remains platform dependent.
  */
-
+type NativeEndpoint struct {
-type Endpoint struct {
 	src unix.RawSockaddrInet6
 	dst unix.RawSockaddrInet6
 }
 
-type IPv4Source struct {
-	src     unix.RawSockaddrInet4
-	Ifindex int32
-}
-
 type NativeBind struct {
 	sock4 int
 	sock6 int
 }
 
+var _ Endpoint = (*NativeEndpoint)(nil)
+var _ Bind = NativeBind{}
+
+type IPv4Source struct {
+	src     unix.RawSockaddrInet4
+	Ifindex int32
+}
+
 func htons(val uint16) uint16 {
 	var out [unsafe.Sizeof(val)]byte
 	binary.BigEndian.PutUint16(out[:], val)
@@ -48,7 +50,11 @@ func ntohs(val uint16) uint16 {
 	return binary.BigEndian.Uint16((*tmp)[:])
 }
 
-func CreateUDPBind(port uint16) (UDPBind, uint16, error) {
+func NewEndpoint() Endpoint {
+	return &NativeEndpoint{}
+}
+
+func CreateUDPBind(port uint16) (Bind, uint16, error) {
 	var err error
 	var bind NativeBind
 
@@ -99,28 +105,33 @@ func (bind NativeBind) Close() error {
 	return err2
 }
 
-func (bind NativeBind) ReceiveIPv6(buff []byte, end *Endpoint) (int, error) {
+func (bind NativeBind) ReceiveIPv6(buff []byte) (int, Endpoint, error) {
-	return receive6(
+	var end NativeEndpoint
+	n, err := receive6(
 		bind.sock6,
 		buff,
-		end,
+		&end,
 	)
+	return n, &end, err
 }
 
-func (bind NativeBind) ReceiveIPv4(buff []byte, end *Endpoint) (int, error) {
+func (bind NativeBind) ReceiveIPv4(buff []byte) (int, Endpoint, error) {
-	return receive4(
+	var end NativeEndpoint
+	n, err := receive4(
 		bind.sock4,
 		buff,
-		end,
+		&end,
 	)
+	return n, &end, err
 }
 
-func (bind NativeBind) Send(buff []byte, end *Endpoint) error {
+func (bind NativeBind) Send(buff []byte, end Endpoint) error {
-	switch end.dst.Family {
+	nend := end.(*NativeEndpoint)
+	switch nend.dst.Family {
 	case unix.AF_INET6:
-		return send6(bind.sock6, end, buff)
+		return send6(bind.sock6, nend, buff)
 	case unix.AF_INET:
-		return send4(bind.sock4, end, buff)
+		return send4(bind.sock4, nend, buff)
 	default:
 		return errors.New("Unknown address family of destination")
 	}
@@ -151,12 +162,12 @@ func sockaddrToString(addr unix.RawSockaddrInet6) string {
 	}
 }
 
-func (end *Endpoint) DstIP() net.IP {
+func rawAddrToIP(addr unix.RawSockaddrInet6) net.IP {
-	switch end.dst.Family {
+	switch addr.Family {
 	case unix.AF_INET6:
-		return end.dst.Addr[:]
+		return addr.Addr[:]
 	case unix.AF_INET:
-		ptr := (*unix.RawSockaddrInet4)(unsafe.Pointer(&end.dst))
+		ptr := (*unix.RawSockaddrInet4)(unsafe.Pointer(&addr))
 		return net.IPv4(
 			ptr.Addr[0],
 			ptr.Addr[1],
@@ -168,25 +179,33 @@ func (end *Endpoint) DstIP() net.IP {
 	}
 }
 
-func (end *Endpoint) DstToBytes() []byte {
+func (end *NativeEndpoint) SrcIP() net.IP {
+	return rawAddrToIP(end.src)
+}
+
+func (end *NativeEndpoint) DstIP() net.IP {
+	return rawAddrToIP(end.dst)
+}
+
+func (end *NativeEndpoint) DstToBytes() []byte {
 	ptr := unsafe.Pointer(&end.src)
 	arr := (*[unix.SizeofSockaddrInet6]byte)(ptr)
 	return arr[:]
 }
 
-func (end *Endpoint) SrcToString() string {
+func (end *NativeEndpoint) SrcToString() string {
 	return sockaddrToString(end.src)
 }
 
-func (end *Endpoint) DstToString() string {
+func (end *NativeEndpoint) DstToString() string {
 	return sockaddrToString(end.dst)
 }
 
-func (end *Endpoint) ClearDst() {
+func (end *NativeEndpoint) ClearDst() {
 	end.dst = unix.RawSockaddrInet6{}
 }
 
-func (end *Endpoint) ClearSrc() {
+func (end *NativeEndpoint) ClearSrc() {
 	end.src = unix.RawSockaddrInet6{}
 }
 
@@ -306,7 +325,7 @@ func create6(port uint16) (int, uint16, error) {
 	return fd, uint16(addr.Port), err
 }
 
-func (end *Endpoint) SetDst(s string) error {
+func (end *NativeEndpoint) SetDst(s string) error {
 	addr, err := parseEndpoint(s)
 	if err != nil {
 		return err
@@ -342,7 +361,7 @@ func (end *Endpoint) SetDst(s string) error {
 	return errors.New("Failed to recognize IP address format")
 }
 
-func send6(sock int, end *Endpoint, buff []byte) error {
+func send6(sock int, end *NativeEndpoint, buff []byte) error {
 
 	// construct message header
 
@@ -404,7 +423,7 @@ func send6(sock int, end *Endpoint, buff []byte) error {
 	return errno
 }
 
-func send4(sock int, end *Endpoint, buff []byte) error {
+func send4(sock int, end *NativeEndpoint, buff []byte) error {
 
 	// construct message header
 
@@ -470,7 +489,7 @@ func send4(sock int, end *Endpoint, buff []byte) error {
 	return errno
 }
 
-func receive4(sock int, buff []byte, end *Endpoint) (int, error) {
+func receive4(sock int, buff []byte, end *NativeEndpoint) (int, error) {
 
 	// contruct message header
 
@@ -518,7 +537,7 @@ func receive4(sock int, buff []byte, end *Endpoint) (int, error) {
 	return int(size), nil
 }
 
-func receive6(sock int, buff []byte, end *Endpoint) (int, error) {
+func receive6(sock int, buff []byte, end *NativeEndpoint) (int, error) {
 
 	// contruct message header
 

src/device.go

@@ -22,7 +22,7 @@ type Device struct {
 	}
 	net struct {
 		mutex  sync.RWMutex
-		bind   UDPBind // bind interface
+		bind   Bind   // bind interface
 		port   uint16 // listening port
 		fwmark uint32 // mark value (0 = disabled)
 	}

src/peer.go

@@ -15,10 +15,7 @@ type Peer struct {
 	keyPairs                    KeyPairs
 	handshake                   Handshake
 	device                      *Device
-	endpoint                    struct {
+	endpoint                    Endpoint
-		set   bool     // has a known endpoint been discovered
-		value Endpoint // source / destination cache
-	}
 	stats                       struct {
 		txBytes           uint64 // bytes send to peer (endpoint)
 		rxBytes           uint64 // bytes received from peer
@@ -110,9 +107,7 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
 
 	// reset endpoint
 
-	peer.endpoint.set = false
+	peer.endpoint = nil
-	peer.endpoint.value.ClearDst()
-	peer.endpoint.value.ClearSrc()
 
 	// prepare queuing
 
@@ -143,16 +138,16 @@ func (peer *Peer) SendBuffer(buffer []byte) error {
 	defer peer.device.net.mutex.RUnlock()
 	peer.mutex.RLock()
 	defer peer.mutex.RUnlock()
-	if !peer.endpoint.set {
+	if peer.endpoint == nil {
 		return errors.New("No known endpoint for peer")
 	}
-	return peer.device.net.bind.Send(buffer, &peer.endpoint.value)
+	return peer.device.net.bind.Send(buffer, peer.endpoint)
 }
 
 /* Returns a short string identification for logging
  */
 func (peer *Peer) String() string {
-	if !peer.endpoint.set {
+	if peer.endpoint == nil {
 		return fmt.Sprintf(
 			"peer(%d unknown %s)",
 			peer.id,
@@ -162,7 +157,7 @@ func (peer *Peer) String() string {
 	return fmt.Sprintf(
 		"peer(%d %s %s)",
 		peer.id,
-		peer.endpoint.value.DstToString(),
+		peer.endpoint.DstToString(),
 		base64.StdEncoding.EncodeToString(peer.handshake.remoteStatic[:]),
 	)
 }

src/receive.go

@@ -93,7 +93,7 @@ func (device *Device) addToHandshakeQueue(
 	}
 }
 
-func (device *Device) RoutineReceiveIncomming(IP int, bind UDPBind) {
+func (device *Device) RoutineReceiveIncomming(IP int, bind Bind) {
 
 	logDebug := device.log.Debug
 	logDebug.Println("Routine, receive incomming, IP version:", IP)
@@ -104,20 +104,21 @@ func (device *Device) RoutineReceiveIncomming(IP int, bind UDPBind) {
 
 		buffer := device.GetMessageBuffer()
 
-		var size int
+		var (
-		var err error
+			err      error
+			size     int
+			endpoint Endpoint
+		)
 
 		for {
 
 			// read next datagram
 
-			var endpoint Endpoint
-
 			switch IP {
 			case ipv4.Version:
-				size, err = bind.ReceiveIPv4(buffer[:], &endpoint)
+				size, endpoint, err = bind.ReceiveIPv4(buffer[:])
 			case ipv6.Version:
-				size, err = bind.ReceiveIPv6(buffer[:], &endpoint)
+				size, endpoint, err = bind.ReceiveIPv6(buffer[:])
 			default:
 				return
 			}
@@ -339,10 +340,7 @@ func (device *Device) RoutineHandshake() {
 
 					writer := bytes.NewBuffer(temp[:0])
 					binary.Write(writer, binary.LittleEndian, reply)
-					device.net.bind.Send(
+					device.net.bind.Send(writer.Bytes(), elem.endpoint)
-						writer.Bytes(),
-						&elem.endpoint,
-					)
 					if err != nil {
 						logDebug.Println("Failed to send cookie reply:", err)
 					}
@@ -395,8 +393,7 @@ func (device *Device) RoutineHandshake() {
 			// update endpoint
 
 			peer.mutex.Lock()
-			peer.endpoint.set = true
+			peer.endpoint = elem.endpoint
-			peer.endpoint.value = elem.endpoint
 			peer.mutex.Unlock()
 
 			// create response
@@ -452,8 +449,7 @@ func (device *Device) RoutineHandshake() {
 			// update endpoint
 
 			peer.mutex.Lock()
-			peer.endpoint.set = true
+			peer.endpoint = elem.endpoint
-			peer.endpoint.value = elem.endpoint
 			peer.mutex.Unlock()
 
 			logDebug.Println("Received handshake initation from", peer)
@@ -527,8 +523,7 @@ func (peer *Peer) RoutineSequentialReceiver() {
 			// update endpoint
 
 			peer.mutex.Lock()
-			peer.endpoint.set = true
+			peer.endpoint = elem.endpoint
-			peer.endpoint.value = elem.endpoint
 			peer.mutex.Unlock()
 
 			// check for keep-alive

src/uapi.go

@@ -53,8 +53,8 @@ func ipcGetOperation(device *Device, socket *bufio.ReadWriter) *IPCError {
 			defer peer.mutex.RUnlock()
 			send("public_key=" + peer.handshake.remoteStatic.ToHex())
 			send("preshared_key=" + peer.handshake.presharedKey.ToHex())
-			if peer.endpoint.set {
+			if peer.endpoint != nil {
-				send("endpoint=" + peer.endpoint.value.DstToString())
+				send("endpoint=" + peer.endpoint.DstToString())
 			}
 
 			nano := atomic.LoadInt64(&peer.stats.lastHandshakeNano)
@@ -255,17 +255,25 @@ func ipcSetOperation(device *Device, socket *bufio.ReadWriter) *IPCError {
 
 			case "endpoint":
 
-				// set endpoint destination and reset handshake timer
+				// set endpoint destination
 
+				err := func() error {
 					peer.mutex.Lock()
-				err := peer.endpoint.value.SetDst(value)
+					defer peer.mutex.Unlock()
-				peer.endpoint.set = (err == nil)
+
-				peer.mutex.Unlock()
+					endpoint := NewEndpoint()
+					if err := endpoint.SetDst(value); err != nil {
+						return err
+					}
+					peer.endpoint = endpoint
+					signalSend(peer.signal.handshakeReset)
+					return nil
+				}()
+
 				if err != nil {
 					logError.Println("Failed to set endpoint:", value)
 					return &IPCError{Code: ipcErrorInvalid}
 				}
-				signalSend(peer.signal.handshakeReset)
 
 			case "persistent_keepalive_interval":