add sni for mws and ws

dialer/ws/dialer.go

@@ -114,7 +114,9 @@ func (d *wsDialer) Handshake(ctx context.Context, conn net.Conn, options ...dial
 	urlObj := url.URL{Scheme: "ws", Host: host, Path: d.md.path}
 	if d.tlsEnabled {
 		urlObj.Scheme = "wss"
-		d.options.TLSConfig.ServerName = host
+		if d.md.sni != "" {
+			d.options.TLSConfig.ServerName = d.md.sni
+		}
 		dialer.TLSClientConfig = d.options.TLSConfig
 		dialer.NetDialTLSContext = func(ctx context.Context, network, addr string) (net.Conn, error) {
 			client, err := util.NewUTLSWebSocketClient(conn, d.options.TLSConfig, d.md.useH2)

dialer/ws/metadata.go

@@ -17,6 +17,7 @@ type metadata struct {
 	host  string
 	path  string
 	useH2 bool
+	sni   string
 
 	handshakeTimeout  time.Duration
 	readHeaderTimeout time.Duration
@@ -68,5 +69,6 @@ func (d *wsDialer) parseMetadata(md mdata.Metadata) (err error) {
 	d.md.tcpKeepaliveCount = mdutil.GetInt(md, "tcp.keepalive.count")
 
 	d.md.useH2 = mdutil.GetBool(md, "h2")
+	d.md.sni = mdutil.GetString(md, "sni")
 	return
 }