\documentclass[a4paper,10pt,twoside]{book}

\usepackage{fancyhdr}
\usepackage[english]{babel}
%\include{doctools}
\setlength{\unitlength}{18mm}
\newcommand{\blob}{ \rule[-.2cm]{.7cm}{1.2cm}}
\newcommand\rblob{\thepage
\begin{picture}(0,0)
\put(-3.2,-\thechapter){\blob}
\end{picture}}

\newcommand\lblob{%
\begin{picture}(0,0)
\put(2.8,-\thechapter){\blob}
\end{picture}%
\thepage}
\usepackage{xepersian}

\settextfont[Scale=1.2]{XB Niloofar}
\setlatintextfont[Scale=1,ExternalLocation,BoldFont={lmroman10-bold},BoldItalicFont={lmroman10-bolditalic},ItalicFont={lmroman10-italic}]{lmroman10-regular}
\setdigitfont[Scale=1]{Lotus}



\pagestyle{fancy}
\cfoot{}





\begin{document}
\fancyhead[R]{} % Front matter may follow here
\clearpage
\fancyhead[RE]{\rightmark}
\fancyhead[RO]{}
\fancyhead[LE]{\lblob}
\fancyhead[LO]{\leftmark}

\chapter{sdf}
\section{sdaaf}
\section{sdfd}
\chapter{sdgf}
sd
\newpage
sd
\chapter{sdgf}
sd
\newpage
sd\chapter{sdgf}
sd
\newpage
sd
\chapter{sdgf}
sd
\newpage
sd
\chapter{sdgf}
sd
\newpage
sd
\chapter{sdgf}
sd
\newpage
sd


\end{document}