Refactor wireguard & add tun support

transport/wireguard/client_bind.go

@@ -0,0 +1,132 @@
+package wireguard
+
+import (
+	"context"
+	"net"
+	"sync"
+
+	"github.com/sagernet/sing/common"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+
+	"golang.zx2c4.com/wireguard/conn"
+)
+
+var _ conn.Bind = (*ClientBind)(nil)
+
+type ClientBind struct {
+	ctx        context.Context
+	dialer     N.Dialer
+	peerAddr   M.Socksaddr
+	connAccess sync.Mutex
+	conn       *wireConn
+}
+
+func NewClientBind(ctx context.Context, dialer N.Dialer, peerAddr M.Socksaddr) *ClientBind {
+	return &ClientBind{
+		ctx:      ctx,
+		dialer:   dialer,
+		peerAddr: peerAddr,
+	}
+}
+
+func (c *ClientBind) connect() (*wireConn, error) {
+	serverConn := c.conn
+	if serverConn != nil {
+		select {
+		case <-serverConn.done:
+			serverConn = nil
+		default:
+			return serverConn, nil
+		}
+	}
+	c.connAccess.Lock()
+	defer c.connAccess.Unlock()
+	serverConn = c.conn
+	if serverConn != nil {
+		select {
+		case <-serverConn.done:
+			serverConn = nil
+		default:
+			return serverConn, nil
+		}
+	}
+	udpConn, err := c.dialer.DialContext(c.ctx, "udp", c.peerAddr)
+	if err != nil {
+		return nil, &wireError{err}
+	}
+	c.conn = &wireConn{
+		Conn: udpConn,
+		done: make(chan struct{}),
+	}
+	return c.conn, nil
+}
+
+func (c *ClientBind) Open(port uint16) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
+	return []conn.ReceiveFunc{c.receive}, 0, nil
+}
+
+func (c *ClientBind) receive(b []byte) (n int, ep conn.Endpoint, err error) {
+	udpConn, err := c.connect()
+	if err != nil {
+		err = &wireError{err}
+		return
+	}
+	n, err = udpConn.Read(b)
+	if err != nil {
+		udpConn.Close()
+		err = &wireError{err}
+	}
+	ep = Endpoint(c.peerAddr)
+	return
+}
+
+func (c *ClientBind) Close() error {
+	c.connAccess.Lock()
+	defer c.connAccess.Unlock()
+	common.Close(common.PtrOrNil(c.conn))
+	return nil
+}
+
+func (c *ClientBind) SetMark(mark uint32) error {
+	return nil
+}
+
+func (c *ClientBind) Send(b []byte, ep conn.Endpoint) error {
+	udpConn, err := c.connect()
+	if err != nil {
+		return err
+	}
+	_, err = udpConn.Write(b)
+	if err != nil {
+		udpConn.Close()
+	}
+	return err
+}
+
+func (c *ClientBind) ParseEndpoint(s string) (conn.Endpoint, error) {
+	return Endpoint(c.peerAddr), nil
+}
+
+func (c *ClientBind) Endpoint() conn.Endpoint {
+	return Endpoint(c.peerAddr)
+}
+
+type wireConn struct {
+	net.Conn
+	access sync.Mutex
+	done   chan struct{}
+}
+
+func (w *wireConn) Close() error {
+	w.access.Lock()
+	defer w.access.Unlock()
+	select {
+	case <-w.done:
+		return net.ErrClosed
+	default:
+	}
+	w.Conn.Close()
+	close(w.done)
+	return nil
+}