initial commit

listener/tun/listener.go

@@ -0,0 +1,96 @@
+package tun
+
+import (
+	"net"
+
+	"github.com/go-gost/gost/v3/pkg/listener"
+	"github.com/go-gost/gost/v3/pkg/logger"
+	md "github.com/go-gost/gost/v3/pkg/metadata"
+	"github.com/go-gost/gost/v3/pkg/registry"
+	tun_util "github.com/go-gost/x/internal/util/tun"
+)
+
+func init() {
+	registry.ListenerRegistry().Register("tun", NewListener)
+}
+
+type tunListener struct {
+	addr    net.Addr
+	cqueue  chan net.Conn
+	closed  chan struct{}
+	logger  logger.Logger
+	md      metadata
+	options listener.Options
+}
+
+func NewListener(opts ...listener.Option) listener.Listener {
+	options := listener.Options{}
+	for _, opt := range opts {
+		opt(&options)
+	}
+	return &tunListener{
+		logger:  options.Logger,
+		options: options,
+	}
+}
+
+func (l *tunListener) Init(md md.Metadata) (err error) {
+	if err = l.parseMetadata(md); err != nil {
+		return
+	}
+
+	l.addr, err = net.ResolveUDPAddr("udp", l.options.Addr)
+	if err != nil {
+		return
+	}
+
+	ifce, ip, err := l.createTun()
+	if err != nil {
+		if ifce != nil {
+			ifce.Close()
+		}
+		return
+	}
+
+	itf, err := net.InterfaceByName(ifce.Name())
+	if err != nil {
+		return
+	}
+
+	addrs, _ := itf.Addrs()
+	l.logger.Infof("name: %s, net: %s, mtu: %d, addrs: %s",
+		itf.Name, ip, itf.MTU, addrs)
+
+	l.cqueue = make(chan net.Conn, 1)
+	l.closed = make(chan struct{})
+
+	conn := tun_util.NewConn(l.md.config, ifce, l.addr, &net.IPAddr{IP: ip})
+
+	l.cqueue <- conn
+
+	return
+}
+
+func (l *tunListener) Accept() (net.Conn, error) {
+	select {
+	case conn := <-l.cqueue:
+		return conn, nil
+	case <-l.closed:
+	}
+
+	return nil, listener.ErrClosed
+}
+
+func (l *tunListener) Addr() net.Addr {
+	return l.addr
+}
+
+func (l *tunListener) Close() error {
+	select {
+	case <-l.closed:
+		return net.ErrClosed
+	default:
+		close(l.closed)
+	}
+	return nil
+}