done

connection.go

@@ -1,5 +1,10 @@
 package tunnel
 
+import (
+	"io"
+	"sync"
+)
+
 type Connection struct {
 	RX     <-chan *DataFrame
 	TX     chan<- *DataFrame
@@ -16,7 +21,14 @@ func (c *Connection) Read(p []byte) (int, error) {
 }
 
 func (c *Connection) Write(p []byte) (int, error) {
-	defer recover()
+	var lock sync.Mutex
+	lock.Lock()
+	defer lock.Unlock()
+
+	if c.closed {
+		return 0, io.ErrClosedPipe
+	}
+
 	df := &DataFrame{
 		ID:   c.ID,
 		Type: TypeNormal,
@@ -30,6 +42,7 @@ func (c *Connection) Write(p []byte) (int, error) {
 }
 
 func (c *Connection) Close() error {
+	var lock sync.Mutex
 	defer close(c.TX)
 	if !c.closed {
 		c.TX <- &DataFrame{
@@ -37,6 +50,8 @@ func (c *Connection) Close() error {
 			Type: TypeClosed,
 		}
 	}
+	lock.Lock()
 	c.closed = true
+	lock.Unlock()
 	return nil
 }

manager.go

@@ -29,6 +29,7 @@ func NewManager(tun io.ReadWriter) *Manager {
 }
 
 func (m *Manager) Run() {
+	onReceiveQueue := make(chan bool)
 	for {
 		select {
 		case <-m.closed:
@@ -40,15 +41,18 @@ func (m *Manager) Run() {
 		case connection := <-m.delConnection:
 			connection.Close()
 			delete(m.Connections, connection.ID)
-		default:
-			go m.onReceive()
+		case onReceiveQueue <- true:
+			go m.onReceive(onReceiveQueue)
 		}
 	}
 }
 
-func (m *Manager) onReceive() {
+func (m *Manager) onReceive(ch chan bool) {
+	<-ch
 	df := new(DataFrame)
-	df.Decode(m.Tunnel)
+	if err := df.Decode(m.Tunnel); err != nil {
+		return
+	}
 	switch df.Type {
 	case TypeRequest:
 		m.accept <- df