add tunnel handler and connector

connector/tunnel/bind.go

@@ -0,0 +1,95 @@
+package tunnel
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"strconv"
+
+	"github.com/go-gost/core/connector"
+	"github.com/go-gost/relay"
+	"github.com/go-gost/x/internal/util/mux"
+)
+
+// Bind implements connector.Binder.
+func (c *tunnelConnector) Bind(ctx context.Context, conn net.Conn, network, address string, opts ...connector.BindOption) (net.Listener, error) {
+	log := c.options.Logger
+
+	addr, cid, err := c.initTunnel(conn, network, address)
+	if err != nil {
+		return nil, err
+	}
+	log.Infof("create tunnel on %s/%s OK, tunnel=%s, connector=%s", addr, network, c.md.tunnelID.String(), cid)
+
+	session, err := mux.ServerSession(conn)
+	if err != nil {
+		return nil, err
+	}
+
+	return &bindListener{
+		network: network,
+		addr:    addr,
+		session: session,
+		logger:  log,
+	}, nil
+}
+
+func (c *tunnelConnector) initTunnel(conn net.Conn, network, address string) (addr net.Addr, cid relay.ConnectorID, err error) {
+	req := relay.Request{
+		Version: relay.Version1,
+		Cmd:     relay.CmdBind,
+	}
+
+	if network == "udp" {
+		req.Cmd |= relay.FUDP
+	}
+
+	if c.options.Auth != nil {
+		pwd, _ := c.options.Auth.Password()
+		req.Features = append(req.Features, &relay.UserAuthFeature{
+			Username: c.options.Auth.Username(),
+			Password: pwd,
+		})
+	}
+
+	af := &relay.AddrFeature{}
+	af.ParseFrom(address)
+
+	req.Features = append(req.Features, af,
+		&relay.TunnelFeature{
+			ID: c.md.tunnelID.ID(),
+		},
+	)
+	if _, err = req.WriteTo(conn); err != nil {
+		return
+	}
+
+	// first reply, bind status
+	resp := relay.Response{}
+	if _, err = resp.ReadFrom(conn); err != nil {
+		return
+	}
+
+	if resp.Status != relay.StatusOK {
+		err = fmt.Errorf("%d: create tunnel %s failed", resp.Status, c.md.tunnelID.String())
+		return
+	}
+
+	for _, f := range resp.Features {
+		switch f.Type() {
+		case relay.FeatureAddr:
+			if feature, _ := f.(*relay.AddrFeature); feature != nil {
+				addr = &bindAddr{
+					network: network,
+					addr:    net.JoinHostPort(feature.Host, strconv.Itoa(int(feature.Port))),
+				}
+			}
+		case relay.FeatureTunnel:
+			if feature, _ := f.(*relay.TunnelFeature); feature != nil {
+				cid = relay.NewConnectorID(feature.ID[:])
+			}
+		}
+	}
+
+	return
+}