try {
            System.arraycopy(this.sbuf, 0, buffer, 0, 4 + SMB1_HEADER_LENGTH);
            final int size = Encdec.dec_uint16be(buffer, 2) & 0xFFFF;
            if (size < SMB1_HEADER_LENGTH + 1 || 4 + size > Math.min(0xFFFF, getContext().getConfig().getMaximumBufferSize())) {
                throw new IOException("Invalid payload size: " + size);
            }