Netlink sockets can't be shutdown

conn_linux.go

@@ -15,6 +15,7 @@
 package main
 
 import (
+	"./rwcancel"
 	"errors"
 	"golang.org/x/sys/unix"
 	"net"
@@ -58,6 +59,7 @@ type NativeBind struct {
 	sock4         int
 	sock6         int
 	netlinkSock   int
+	netlinkCancel *rwcancel.RWCancel
 	lastMark      uint32
 }
 
@@ -125,18 +127,23 @@ func CreateBind(port uint16, device *Device) (*NativeBind, uint16, error) {
 	if err != nil {
 		return nil, 0, err
 	}
+	bind.netlinkCancel, err = rwcancel.NewRWCancel(bind.netlinkSock)
+	if err != nil {
+		unix.Close(bind.netlinkSock)
+		return nil, 0, err
+	}
 
 	go bind.routineRouteListener(device)
 
 	bind.sock6, port, err = create6(port)
 	if err != nil {
-		unix.Close(bind.netlinkSock)
+		bind.netlinkCancel.Cancel()
 		return nil, port, err
 	}
 
 	bind.sock4, port, err = create4(port)
 	if err != nil {
-		unix.Close(bind.netlinkSock)
+		bind.netlinkCancel.Cancel()
 		unix.Close(bind.sock6)
 	}
 	return &bind, port, err
@@ -178,7 +185,8 @@ func closeUnblock(fd int) error {
 func (bind *NativeBind) Close() error {
 	err1 := closeUnblock(bind.sock6)
 	err2 := closeUnblock(bind.sock4)
-	err3 := closeUnblock(bind.netlinkSock)
+	err3 := bind.netlinkCancel.Cancel()
+
 	if err1 != nil {
 		return err1
 	}
@@ -539,8 +547,20 @@ func receive6(sock int, buff []byte, end *NativeEndpoint) (int, error) {
 func (bind *NativeBind) routineRouteListener(device *Device) {
 	var reqPeer map[uint32]*Peer
 
+	defer unix.Close(bind.netlinkSock)
+
 	for msg := make([]byte, 1<<16); ; {
-		msgn, _, _, _, err := unix.Recvmsg(bind.netlinkSock, msg[:], nil, 0)
+		var err error
+		var msgn int
+		for {
+			msgn, _, _, _, err = unix.Recvmsg(bind.netlinkSock, msg[:], nil, 0)
+			if err == nil || !rwcancel.ErrorIsEAGAIN(err) {
+				break
+			}
+			if !bind.netlinkCancel.ReadyRead() {
+				return
+			}
+		}
 		if err != nil {
 			return
 		}

main.go

@@ -221,14 +221,10 @@ func main() {
 		return
 	}
 
-	// create wireguard device
-
 	device := NewDevice(tun, logger)
 
 	logger.Info.Println("Device started")
 
-	// start uapi listener
-
 	errs := make(chan error)
 	term := make(chan os.Signal)
 

tun_darwin.go

@@ -122,11 +122,13 @@ func CreateTUNFromFile(file *os.File) (TUNDevice, error) {
 
 	_, err := tun.Name()
 	if err != nil {
+		tun.fd.Close()
 		return nil, err
 	}
 
 	tun.rwcancel, err = rwcancel.NewRWCancel(int(file.Fd()))
 	if err != nil {
+		tun.fd.Close()
 		return nil, err
 	}
 

tun_linux.go

@@ -32,13 +32,15 @@ const (
 
 type NativeTun struct {
 	fd            *os.File
+	fdCancel      *rwcancel.RWCancel
 	index         int32         // if index
 	name          string        // name of interface
 	errors        chan error    // async error handling
 	events        chan TUNEvent // device related events
 	nopi          bool          // the device was pased IFF_NO_PI
-	rwcancel                *rwcancel.RWCancel
 	netlinkSock   int
+	netlinkCancel *rwcancel.RWCancel
+
 	statusListenersShutdown chan struct{}
 }
 
@@ -86,9 +88,22 @@ func createNetlinkSocket() (int, error) {
 }
 
 func (tun *NativeTun) RoutineNetlinkListener() {
+	defer unix.Close(tun.netlinkSock)
+
 	for msg := make([]byte, 1<<16); ; {
 
-		msgn, _, _, _, err := unix.Recvmsg(tun.netlinkSock, msg[:], nil, 0)
+		var err error
+		var msgn int
+		for {
+			msgn, _, _, _, err = unix.Recvmsg(tun.netlinkSock, msg[:], nil, 0)
+			if err == nil || !rwcancel.ErrorIsEAGAIN(err) {
+				break
+			}
+			if !tun.netlinkCancel.ReadyRead() {
+				tun.errors <- fmt.Errorf("netlink socket closed: %s", err.Error())
+				return
+			}
+		}
 		if err != nil {
 			tun.errors <- fmt.Errorf("failed to receive netlink message: %s", err.Error())
 			return
@@ -323,7 +338,7 @@ func (tun *NativeTun) Read(buff []byte, offset int) (int, error) {
 		if err == nil || !rwcancel.ErrorIsEAGAIN(err) {
 			return n, err
 		}
-		if !tun.rwcancel.ReadyRead() {
+		if !tun.fdCancel.ReadyRead() {
 			return 0, errors.New("tun device closed")
 		}
 	}
@@ -334,10 +349,13 @@ func (tun *NativeTun) Events() chan TUNEvent {
 }
 
 func (tun *NativeTun) Close() error {
+	var err1 error
 	close(tun.statusListenersShutdown)
-	err1 := closeUnblock(tun.netlinkSock)
+	if tun.netlinkCancel != nil {
+		err1 = tun.netlinkCancel.Cancel()
+	}
 	err2 := tun.fd.Close()
-	err3 := tun.rwcancel.Cancel()
+	err3 := tun.fdCancel.Cancel()
 	close(tun.events)
 
 	if err1 != nil {
@@ -404,13 +422,15 @@ func CreateTUNFromFile(fd *os.File) (TUNDevice, error) {
 	}
 	var err error
 
-	tun.rwcancel, err = rwcancel.NewRWCancel(int(fd.Fd()))
+	tun.fdCancel, err = rwcancel.NewRWCancel(int(fd.Fd()))
 	if err != nil {
+		tun.fd.Close()
 		return nil, err
 	}
 
 	_, err = tun.Name()
 	if err != nil {
+		tun.fd.Close()
 		return nil, err
 	}
 
@@ -423,6 +443,12 @@ func CreateTUNFromFile(fd *os.File) (TUNDevice, error) {
 
 	tun.netlinkSock, err = createNetlinkSocket()
 	if err != nil {
+		tun.fd.Close()
+		return nil, err
+	}
+	tun.netlinkCancel, err = rwcancel.NewRWCancel(tun.netlinkSock)
+	if err != nil {
+		tun.fd.Close()
 		return nil, err
 	}