Smb2NegotiateResponse r = null;
        byte[] negoReqBuffer = null;
        byte[] negoRespBuffer = null;
        try {
            smb2neg.setRequestCredits(Math.max(1, this.desiredCredits - this.credits.availablePermits()));

            int reqLen = negotiateWrite(smb2neg, first != null);

            WriterThread w = new WriterThread();
            w.setDaemon(true);

            try {
                w.start();
                // use commonly acceptable buffer size
                int bsize = Math.min(sh.getReceiveBufferSize() - 70, dh.getSendBufferSize() - 70);
                byte[][] b = new byte[2][bsize];
                copyRecursive(dest, b, bsize, w, sh, dh);
            }
            finally {

                if ( sk != null ) {
                    // session key is truncated to 16 bytes, right padded with 0 if shorter
                    byte[] key = new byte[16];
                    System.arraycopy(sk, 0, key, 0, Math.min(16, sk.length));
                    this.sessionKey = key;
                }

                boolean signed = response != null && response.isSigned();