/**
     * @return
     * @throws IOException
     */
    private int negotiateWrite(final CommonServerMessageBlockRequest req, final boolean setmid) throws IOException {
        if (setmid) {
            makeKey(req);
        } else {
            req.setMid(0);
            this.mid.set(1);
        }
        final int n = req.encode(this.sbuf, 4);

                    response = new SmbComSessionSetupAndXResponse(getContext().getConfig(), null);
                    response.setExtendedSecurity(true);
                    request.setUid(getUid());
                    setUid(0);

                    try {
                        trans.send(request, response);
                    } catch (SmbAuthException sae) {
                        throw sae;