bare for use

connection.go

@@ -1,9 +1,10 @@
 package tunnel
 
 type Connection struct {
-	RX <-chan *DataFrame
-	TX chan<- *DataFrame
-	ID ID
+	RX     <-chan *DataFrame
+	TX     chan<- *DataFrame
+	ID     ID
+	closed bool
 }
 
 func (c *Connection) Read(p []byte) (int, error) {
@@ -30,5 +31,12 @@ func (c *Connection) Write(p []byte) (int, error) {
 
 func (c *Connection) Close() error {
 	defer close(c.TX)
+	if !c.closed {
+		c.TX <- &DataFrame{
+			ID:   c.ID,
+			Type: TypeClosed,
+		}
+	}
+	c.closed = true
 	return nil
 }

go.mod

@@ -1,3 +1,5 @@
 module git.sense-t.eu.org/senset/tunnel
 
 go 1.19
+
+require github.com/google/uuid v1.3.0

go.sum

@@ -0,0 +1,2 @@
+github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
+github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=

manager.go

@@ -1,25 +1,30 @@
 package tunnel
 
 import (
+	"errors"
 	"io"
 )
 
 type Manager struct {
-	Tunnel      io.ReadWriter
-	Connections map[ID]*Connection
-	incoming    chan *DataFrame
-	outgoing    chan *DataFrame
-	accept      chan *DataFrame
-	closed      chan bool
+	Tunnel        io.ReadWriter
+	Connections   map[ID]*Connection
+	incoming      chan *DataFrame
+	outgoing      chan *DataFrame
+	accept        chan *DataFrame
+	closed        chan bool
+	newConnection chan *Connection
+	delConnection chan *Connection
 }
 
 func NewManager(tun io.ReadWriter) *Manager {
 	return &Manager{
-		Tunnel:      tun,
-		Connections: make(map[ID]*Connection),
-		incoming:    make(chan *DataFrame, 1024),
-		outgoing:    make(chan *DataFrame, 1024),
-		accept:      make(chan *DataFrame, 1024),
+		Tunnel:        tun,
+		Connections:   make(map[ID]*Connection),
+		incoming:      make(chan *DataFrame, 1024),
+		outgoing:      make(chan *DataFrame, 1024),
+		accept:        make(chan *DataFrame, 1024),
+		newConnection: make(chan *Connection),
+		delConnection: make(chan *Connection),
 	}
 }
 
@@ -30,34 +35,73 @@ func (m *Manager) Run() {
 			return
 		case df := <-m.incoming:
 			go df.Encode(m.Tunnel)
+		case connection := <-m.newConnection:
+			m.Connections[connection.ID] = connection
+		case connection := <-m.delConnection:
+			connection.Close()
+			delete(m.Connections, connection.ID)
 		default:
-			go func() {
-				df := new(DataFrame)
-				df.Decode(m.Tunnel)
-				switch df.Type {
-				case TypeRequest:
-					m.accept <- df
-				case TypeClosed:
-					connection, ok := m.Connections[df.ID]
-					if ok {
-						connection.Close()
-						delete(m.Connections, df.ID)
-					}
-				case TypeNormal:
-					connection, ok := m.Connections[df.ID]
-					if ok {
-						connection.RX = m.outgoing
-						m.outgoing <- df
-					}
-				}
-			}()
+			go m.onReceive()
 		}
 	}
 }
 
-func (m *Manager) Connect()
+func (m *Manager) onReceive() {
+	df := new(DataFrame)
+	df.Decode(m.Tunnel)
+	switch df.Type {
+	case TypeRequest:
+		m.accept <- df
+	case TypeClosed:
+		connection, ok := m.Connections[df.ID]
+		if ok {
+			m.delConnection <- connection
+		}
+	case TypeNormal:
+		connection, ok := m.Connections[df.ID]
+		if ok {
+			connection.RX = m.outgoing
+			m.outgoing <- df
+		}
+	}
+}
 
-func (m *Manager) Accept()
+func (m *Manager) Connect() (*Connection, error) {
+	df := &DataFrame{
+		ID:   NewID(),
+		Type: TypeRequest,
+	}
+	connection := &Connection{
+		ID: df.ID,
+		TX: m.incoming,
+	}
+	m.newConnection <- connection
+	m.incoming <- df
+
+	df = <-connection.RX
+	if df.Type != TypeConnected {
+
+		return nil, errors.New("failed to connect")
+	}
+	return connection, nil
+}
+
+func (m *Manager) Accept() (*Connection, error) {
+	df := <-m.accept
+	if df.Type != TypeRequest {
+		return nil, errors.New("failed to accept")
+	}
+	connection := &Connection{
+		ID: df.ID,
+		TX: m.incoming,
+	}
+	m.newConnection <- connection
+
+	df.Type = TypeConnected
+	m.incoming <- df
+
+	return connection, nil
+}
 
 func (m *Manager) Close() error {
 	defer close(m.closed)

types.go

@@ -1,4 +1,11 @@
 package tunnel
 
+import "github.com/google/uuid"
+
 type ID string
+
+func NewID() ID {
+	return ID(uuid.NewString())
+}
+
 type Type uint8