if host, _, err := net.SplitHostPort(sconn.RemoteAddr().String()); err == nil {
			remoteIP = host
		}
		server := sftp.NewRequestServer(channel, NewSFTPDriver(sconn.Permissions, remoteIP), sftp.WithRSAllocator())
		defer server.Close()
		server.Serve()
	}

	sftpServer, err := xsftp.NewServer(&xsftp.Options{
		PublicIP: publicIP,
		Port:     port,
		// OpensSSH default handshake timeout is 2 minutes.