Refactor wireguard & add tun support

transport/wireguard/server_bind.go

@@ -0,0 +1,96 @@
+package wireguard
+
+import (
+	"io"
+
+	"github.com/sagernet/sing/common/buf"
+	E "github.com/sagernet/sing/common/exceptions"
+	M "github.com/sagernet/sing/common/metadata"
+	N "github.com/sagernet/sing/common/network"
+
+	"golang.zx2c4.com/wireguard/conn"
+)
+
+var _ conn.Bind = (*ServerBind)(nil)
+
+type ServerBind struct {
+	inbound   chan serverPacket
+	done      chan struct{}
+	writeBack N.PacketWriter
+}
+
+func NewServerBind(writeBack N.PacketWriter) *ServerBind {
+	return &ServerBind{
+		inbound:   make(chan serverPacket, 256),
+		done:      make(chan struct{}),
+		writeBack: writeBack,
+	}
+}
+
+func (s *ServerBind) Abort() error {
+	select {
+	case <-s.done:
+		return io.ErrClosedPipe
+	default:
+		close(s.done)
+	}
+	return nil
+}
+
+type serverPacket struct {
+	buffer *buf.Buffer
+	source M.Socksaddr
+}
+
+func (s *ServerBind) Open(port uint16) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
+	fns = []conn.ReceiveFunc{s.receive}
+	return
+}
+
+func (s *ServerBind) receive(b []byte) (n int, ep conn.Endpoint, err error) {
+	select {
+	case packet := <-s.inbound:
+		defer packet.buffer.Release()
+		n = copy(b, packet.buffer.Bytes())
+		ep = Endpoint(packet.source)
+		return
+	case <-s.done:
+		err = io.ErrClosedPipe
+		return
+	}
+}
+
+func (s *ServerBind) WriteIsThreadUnsafe() {
+}
+
+func (s *ServerBind) WritePacket(buffer *buf.Buffer, destination M.Socksaddr) error {
+	select {
+	case s.inbound <- serverPacket{
+		buffer: buffer,
+		source: destination,
+	}:
+		return nil
+	case <-s.done:
+		return io.ErrClosedPipe
+	}
+}
+
+func (s *ServerBind) Close() error {
+	return nil
+}
+
+func (s *ServerBind) SetMark(mark uint32) error {
+	return nil
+}
+
+func (s *ServerBind) Send(b []byte, ep conn.Endpoint) error {
+	return s.writeBack.WritePacket(buf.As(b), M.Socksaddr(ep.(Endpoint)))
+}
+
+func (s *ServerBind) ParseEndpoint(addr string) (conn.Endpoint, error) {
+	destination := M.ParseSocksaddr(addr)
+	if !destination.IsValid() || destination.Port == 0 {
+		return nil, E.New("invalid endpoint: ", addr)
+	}
+	return Endpoint(destination), nil
+}