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\documentclass[dvipsnames,14pt,t]{beamer}
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\usepackage{beamerthemeplainculight}
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\usepackage[T1]{fontenc}
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\usepackage[latin1]{inputenc}
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\usepackage{mathpartir}
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\usepackage[absolute,overlay]{textpos}
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\usepackage{ifthen}
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\usepackage{tikz}
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\usepackage{pgf}
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\usepackage{calc}
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\usepackage{ulem}
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\usepackage{courier}
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\usepackage{listings}
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\renewcommand{\uline}[1]{#1}
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\usetikzlibrary{arrows}
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\usetikzlibrary{automata}
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\usetikzlibrary{shapes}
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\usetikzlibrary{shadows}
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\usetikzlibrary{positioning}
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\usetikzlibrary{calc}
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\usepackage{graphicx}
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\definecolor{javadocblue}{rgb}{0.25,0.35,0.75} % javadoc
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\lstset{language=Java,
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basicstyle=\ttfamily,
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morecomment=[s][\color{javadocblue}]{/**}{*/},
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\lstdefinelanguage{scala}{
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morekeywords={abstract,case,catch,class,def,%
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do,else,extends,false,final,finally,%
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for,if,implicit,import,match,mixin,%
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new,null,object,override,package,%
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private,protected,requires,return,sealed,%
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super,this,throw,trait,true,try,%
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type,val,var,while,with,yield},
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otherkeywords={=>,<-,<\%,<:,>:,\#,@},
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morecomment=[l]{//},
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morecomment=[n]{/*}{*/},
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morestring=[b]",
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morestring=[b]',
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morestring=[b]"""
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}
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\lstset{language=Scala,
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basicstyle=\ttfamily,
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keywordstyle=\color{javapurple}\bfseries,
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commentstyle=\color{javagreen},
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morecomment=[s][\color{javadocblue}]{/**}{*/},
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tabsize=2,
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showspaces=false,
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showstringspaces=false}
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% beamer stuff
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\renewcommand{\slidecaption}{APP 02, King's College London, 9 October 2012}
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\begin{document}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}<1>[t]
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\frametitle{%
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\begin{tabular}{@ {}c@ {}}
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\\
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\LARGE Access Control and \\[-3mm]
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\LARGE Privacy Policies (3)\\[-6mm]
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\end{tabular}}\bigskip\bigskip\bigskip
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%\begin{center}
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%\includegraphics[scale=1.3]{pics/barrier.jpg}
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%\end{center}
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\normalsize
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\begin{center}
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\begin{tabular}{ll}
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Email: & christian.urban at kcl.ac.uk\\
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Of$\!$fice: & S1.27 (1st floor Strand Building)\\
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Slides: & KEATS (also home work is there)\\
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& \alert{\bf (I have put a temporary link in there.)}\\
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\end{tabular}
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\end{center}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\begin{center}
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\includegraphics[scale=0.45]{pics/trainwreck.jpg}\\
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one general defence mechanism is\\\alert{\bf defence in depth}
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\end{center}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}<1-2>[c]
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\frametitle{Defence in Depth}
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\begin{itemize}
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\item \alt<1>{overlapping}{{\LARGE\bf overlapping}} systems designed to provide\\ security even if one of them fails.
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\end{itemize}
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\only<2->{
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\begin{textblock}{11}(2,12)
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\small otherwise your ``added security'' can become the point of failure
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\end{textblock}}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{PALs}
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\begin{itemize}
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\item \alert{Permissive Action Links} prevent unauthorised use of nuclear weapons (so the theory)
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\end{itemize}
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\begin{center}
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\includegraphics[scale=0.25]{pics/nuclear1.jpg}\hspace{3mm}
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\includegraphics[scale=0.25]{pics/nuclear2.jpg}
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\end{center}
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\onslide<3->{
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modern PALs also include a 2-person rule
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}
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\only<2->{
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\begin{textblock}{11}(3,2)
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\begin{tikzpicture}
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\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm]
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{\begin{minipage}{8cm}
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US Air Force's Strategic Air Command worried that in times of need the
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codes would not be available, so until 1977 quietly decided to set them
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to 00000000\ldots
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\end{minipage}};
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\end{tikzpicture}
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\end{textblock}}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\begin{itemize}
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\item until 1998, Britain had nuclear weapons that could be launched from airplanes\bigskip\pause
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\item these weapons were armed with a bicycle key
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\begin{center}
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\begin{tabular}[b]{c}
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\includegraphics[scale=1.05]{pics/britkeys1.jpg}\\
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\small nuclear weapon keys
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\end{tabular}
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\hspace{3mm}
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\begin{tabular}[b]{c}
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\includegraphics[scale=0.35]{pics/britkeys2.jpg}\\
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\small bicycle lock
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\end{tabular}
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\end{center}\bigskip\pause
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\item the current Trident nuclear weapons can be launched from a submarine without any code being transmitted
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\end{itemize}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{Access Control in Unix}
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\begin{itemize}
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\item access control provided by the OS
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\item authenticate principals (login)
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\item mediate access to files, ports, processes according to \alert{roles} (user ids)\\
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\item roles get attached with privileges\bigskip\\%
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\hspace{8mm}
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\begin{tikzpicture}
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\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm]
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{\begin{minipage}{8cm}
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\alert{principle of least privilege:}\\
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programs should only have as much privilege as they need
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\end{minipage}};
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\end{tikzpicture}
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\end{itemize}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{Access Control in Unix (2)}
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\begin{itemize}
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\item the idea is to restrict access to files and therefore lower the consequences of an attack\\[1cm]\mbox{}
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\end{itemize}
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\begin{textblock}{1}(2.5,9.5)
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\begin{tikzpicture}[scale=1]
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\draw[line width=1mm] (-.3, 0) rectangle (1.5,2);
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\draw (4.7,1) node {Internet};
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\draw (0.6,1.7) node {\footnotesize Interface};
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\draw (0.6,-0.4) node {\footnotesize \begin{tabular}{c}unpriviledged\\[-1mm] process\end{tabular}};
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\draw (-2.7,-0.4) node {\footnotesize \begin{tabular}{c}priviledged\\[-1mm] process\end{tabular}};
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\draw[line width=1mm] (-1.8, 0) rectangle (-3.6,2);
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\draw[white] (1.7,1) node (X) {};
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\draw[white] (3.7,1) node (Y) {};
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\draw[red, <->, line width = 2mm] (X) -- (Y);
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\draw[red, <->, line width = 1mm] (-0.6,1) -- (-1.6,1);
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\end{tikzpicture}
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\end{textblock}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[t]
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\frametitle{Process Ownership}
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\begin{itemize}
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\item access control in Unix is very coarse
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\end{itemize}\bigskip\bigskip\bigskip
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\begin{center}
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\begin{tabular}{c}
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root\\
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\hline
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user$_1$ user$_2$ \ldots www, mail, lp
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\end{tabular}
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\end{center}\bigskip\bigskip\bigskip
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\textcolor{gray}{\small root has UID $=$ 0}\\\pause
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\textcolor{gray}{\small you also have groups that can share access to a file}\\
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\textcolor{gray}{\small but it is difficult to exclude access selectively}\\
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{Access Control in Unix (2)}
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\begin{itemize}
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\item privileges are specified by file access permissions (``everything is a file'')
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\item there are 9 (plus 2) bits that specify the permissions of a file
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\begin{center}
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\begin{tabular}{l}
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\texttt{\$ ls - la}\\
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\texttt{-rwxrw-r-{}- \hspace{3mm} foo\_file.txt}
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\end{tabular}
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\end{center}
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\end{itemize}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{Login Process}
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\begin{itemize}
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\item login processes run under UID $=$ 0\medskip
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\begin{center}
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\texttt{ps -axl | grep login}
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\end{center}\medskip
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\item after login, shells run under UID $=$ user (e.g.~501)\medskip
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\begin{center}
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\texttt{id cu}
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\end{center}\medskip\pause
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\item non-root users are not allowed to change the UID --- would break
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access control
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\item but needed for example for \texttt{passwd}
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\end{itemize}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{Setuid and Setgid}
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The solution is that unix file permissions are 9 + \underline{2 Bits}:
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\alert{Setuid} and \alert{Setgid} Bits
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\begin{itemize}
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\item When a file with setuid is executed, the resulting process will assume the UID given to the owner of the file.
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\item This enables users to create processes as root (or another user).\bigskip
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\item Essential for changing passwords, for example.
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\end{itemize}
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\begin{center}
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\texttt{chmod 4755 fobar\_file}
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\end{center}
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\end{frame}}
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\mode<presentation>{
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\begin{frame}[c]
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\frametitle{\begin{tabular}{c}Privilege Separation in\\ OpenSSH\end{tabular}}
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\begin{center}
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\begin{tikzpicture}[scale=1]
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\draw[line width=1mm] (0, 1.1) rectangle (1.2,2);
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\draw (4.7,1) node {Internet};
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\draw (0.6,1.7) node {\footnotesize Slave};
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\draw[line width=1mm] (0, 0) rectangle (1.2,0.9);
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365 |
\draw (0.6,1.7) node {\footnotesize Slave};
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\draw (0.6,0.6) node {\footnotesize Slave};
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367 |
\draw (0.6,-0.5) node {\footnotesize \begin{tabular}{c}unpriviledged\\[-1mm] processes\end{tabular}};
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\draw (-2.7,-0.4) node {\footnotesize \begin{tabular}{c}priviledged\\[-1mm] process\end{tabular}};
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369 |
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\draw[line width=1mm] (-1.8, 0) rectangle (-3.6,2);
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371 |
\draw (-2.9,1.7) node {\footnotesize Monitor};
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\draw[white] (1.7,1) node (X) {};
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\draw[white] (3.7,1) node (Y) {};
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375 |
\draw[red, <->, line width = 2mm] (X) -- (Y);
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376 |
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\draw[red, <->, line width = 1mm] (-0.4,1.4) -- (-1.4,1.1);
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\draw[red, <->, line width = 1mm] (-0.4,0.6) -- (-1.4,0.9);
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\end{tikzpicture}
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381 |
\end{center}
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29
|
382 |
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\begin{itemize}
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384 |
\item pre-authorisation slave
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385 |
\item post-authorisation\bigskip
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|
386 |
\item 25\% codebase is privileged, 75\% is unprivileged
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387 |
\end{itemize}
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28
|
388 |
\end{frame}}
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29
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389 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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392 |
\mode<presentation>{
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393 |
\begin{frame}[c]
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29
|
394 |
\frametitle{Network Applications}
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28
|
395 |
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29
|
396 |
ideally network application in Unix should be designed as follows:
|
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|
397 |
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398 |
\begin{itemize}
|
|
|
399 |
\item need two distinct processes
|
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|
400 |
\begin{itemize}
|
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|
401 |
\item one that listens to the network; has no privilege
|
|
|
402 |
\item one that is privileged and listens to the latter only (but does not trust it)
|
|
|
403 |
|
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|
404 |
\end{itemize}
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405 |
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|
406 |
\item to implement this you need a parent process, which forks a child process
|
|
|
407 |
\item this child process drops privileges and listens to hostile data\medskip
|
|
|
408 |
|
|
|
409 |
\item after authentication the parent forks again and the new child becomes the user
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|
410 |
\end{itemize}
|
|
|
411 |
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|
412 |
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|
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\end{frame}}
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|
|
414 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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415 |
|
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28
|
416 |
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29
|
417 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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|
418 |
\mode<presentation>{
|
|
|
419 |
\begin{frame}[c]
|
|
|
420 |
\frametitle{\begin{tabular}{@ {}c@ {}}Famous Security Flaws in Unix\end{tabular}}
|
|
|
421 |
|
|
|
422 |
|
|
|
423 |
\begin{itemize}
|
|
|
424 |
\item \texttt{lpr} unfortunately runs with root privileges; you had the option to delete files after printing \ldots\pause\pause
|
|
|
425 |
\item for debugging purposes (FreeBSD) Unix provides a ``core dump'', but allowed to follow links \ldots\pause
|
|
|
426 |
\item \texttt{mkdir foo} is owned by root\medskip
|
|
|
427 |
\begin{center}
|
|
|
428 |
\texttt{-rwxr-xr-x 1 root wheel /bin/mkdir}
|
|
|
429 |
\end{center}\medskip
|
|
|
430 |
it first creates an i-node as root and then changes to ownership to the user's id\\ \textcolor{gray}{\small (automated with a shell script)}
|
|
|
431 |
\end{itemize}
|
|
|
432 |
|
|
|
433 |
\only<1>{
|
|
|
434 |
\begin{textblock}{1}(3,3)
|
|
|
435 |
\begin{tikzpicture}
|
|
|
436 |
\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm]
|
|
|
437 |
{\begin{minipage}{8cm}
|
|
|
438 |
Only failure makes us experts.
|
|
|
439 |
-- Theo de Raadt (OpenBSD, OpenSSH)
|
|
|
440 |
\end{minipage}};
|
|
|
441 |
\end{tikzpicture}
|
|
|
442 |
\end{textblock}}
|
|
|
443 |
|
|
|
444 |
|
|
|
445 |
|
|
28
|
446 |
\end{frame}}
|
|
|
447 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
448 |
|
|
|
449 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
450 |
\mode<presentation>{
|
|
|
451 |
\begin{frame}[c]
|
|
29
|
452 |
\frametitle{\begin{tabular}{@ {}c@ {}}Other Problems\end{tabular}}
|
|
28
|
453 |
|
|
29
|
454 |
There are thing's you just cannot solve on the programming side:\bigskip
|
|
28
|
455 |
|
|
29
|
456 |
\begin{itemize}
|
|
|
457 |
\item for system maintenance you often have \texttt{cron}-jobs cleaning \texttt{/tmp}\medskip
|
|
|
458 |
\begin{itemize}
|
|
|
459 |
\item attacker:\\
|
|
|
460 |
\texttt{mkdir /tmp/a; cat > /tmp/a/passwd}
|
|
|
461 |
\item root:\\\texttt{rm /tmp/*/*}:
|
|
|
462 |
\item attacker:\\
|
|
|
463 |
\texttt{rm /tmp/a/passwd; rmdir /tmp/a;}\\\texttt{ln -s /etc /tmp/a}
|
|
|
464 |
\end{itemize}
|
|
|
465 |
\end{itemize}
|
|
28
|
466 |
|
|
|
467 |
\end{frame}}
|
|
|
468 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
469 |
|
|
|
470 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
471 |
\mode<presentation>{
|
|
|
472 |
\begin{frame}[c]
|
|
29
|
473 |
\frametitle{\begin{tabular}{@ {}c@ {}}Security Levels\end{tabular}}
|
|
|
474 |
|
|
|
475 |
Unix essentially can only distinguish between two security levels (root and non-root).
|
|
28
|
476 |
|
|
|
477 |
\begin{itemize}
|
|
29
|
478 |
\item In military applications you often have many security levels (top-secret, secret, confidential, unclassified)\bigskip\pause
|
|
28
|
479 |
|
|
29
|
480 |
\item Information flow: Bell --- La Pudela model
|
|
28
|
481 |
|
|
|
482 |
\begin{itemize}
|
|
29
|
483 |
\item read: your own level and below
|
|
|
484 |
\item write: your own level and above
|
|
|
485 |
\end{itemize}
|
|
|
486 |
\end{itemize}
|
|
28
|
487 |
|
|
|
488 |
\end{frame}}
|
|
|
489 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
490 |
|
|
|
491 |
|
|
|
492 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
493 |
\mode<presentation>{
|
|
|
494 |
\begin{frame}[c]
|
|
29
|
495 |
\frametitle{\begin{tabular}{@ {}c@ {}}Security Levels (2)\end{tabular}}
|
|
28
|
496 |
|
|
29
|
497 |
\begin{itemize}
|
|
|
498 |
\item Bell --- La Pudela preserves data secrecy, but not data integrity\bigskip\pause
|
|
|
499 |
|
|
|
500 |
\item Biba model is for data integrity
|
|
28
|
501 |
|
|
29
|
502 |
\begin{itemize}
|
|
|
503 |
\item read: your own level and above
|
|
|
504 |
\item write: your own level and below
|
|
|
505 |
\end{itemize}
|
|
|
506 |
\end{itemize}
|
|
28
|
507 |
|
|
|
508 |
\end{frame}}
|
|
|
509 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
510 |
|
|
|
511 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
512 |
\mode<presentation>{
|
|
|
513 |
\begin{frame}[c]
|
|
29
|
514 |
\frametitle{\begin{tabular}{@ {}c@ {}}Access Control in 2000\end{tabular}}
|
|
|
515 |
|
|
|
516 |
According to Ross Anderson (1st edition of his book), some senior Microsoft people held the
|
|
|
517 |
following view:
|
|
|
518 |
|
|
|
519 |
\begin{center}
|
|
|
520 |
\begin{tikzpicture}
|
|
|
521 |
\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm]
|
|
|
522 |
{\begin{minipage}{10.5cm}
|
|
|
523 |
\small Access control does not matter. Computers are becoming single-purpose
|
|
|
524 |
or single-user devices. Single-purpose devices, such as Web servers that deliver a single service, don't
|
|
|
525 |
need much in the way of access control as there's nothing for operating system access controls
|
|
|
526 |
to do; the job of separating users from each other is best left to application code. As for the PC
|
|
|
527 |
on your desk, if all the software on it comes from a single source, then again there's no need
|
|
|
528 |
for the operating system to provide separation. \hfill{}\textcolor{gray}{(in 2000)}
|
|
|
529 |
\end{minipage}};
|
|
|
530 |
\end{tikzpicture}
|
|
|
531 |
\end{center}
|
|
|
532 |
|
|
|
533 |
\end{frame}}
|
|
|
534 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
535 |
|
|
|
536 |
|
|
|
537 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
538 |
\mode<presentation>{
|
|
|
539 |
\begin{frame}[t]
|
|
|
540 |
\frametitle{\begin{tabular}{@ {}c@ {}}Research Problems\end{tabular}}
|
|
28
|
541 |
|
|
|
542 |
\begin{itemize}
|
|
29
|
543 |
\item with access control we are back to 1970s\bigskip
|
|
28
|
544 |
|
|
29
|
545 |
\only<1>{
|
|
|
546 |
\begin{tikzpicture}
|
|
|
547 |
\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm]
|
|
|
548 |
{\begin{minipage}{10cm}
|
|
|
549 |
\small Going all the way back to early time-sharing systems we systems people regarded the users, and any code they wrote, as the mortal enemies of us and each other. We were like the police force in a violent slum.\\
|
|
|
550 |
\mbox{}\hfill--- Roger Needham
|
|
|
551 |
\end{minipage}};
|
|
|
552 |
\end{tikzpicture}}\pause
|
|
|
553 |
|
|
|
554 |
\item the largest research area in access control in 2000-07 has been ``Trusted Computing'', but thankfully it
|
|
|
555 |
is dead now\bigskip
|
|
|
556 |
\item a useful research area is to not just have robust access control, but also usable access control --- by programmers and users\\
|
|
|
557 |
(one possible answer is operating system virtualisation, e.g.~Xen, VMWare)\medskip\pause
|
|
|
558 |
|
|
|
559 |
\item electronic voting
|
|
28
|
560 |
\end{itemize}
|
|
|
561 |
\end{frame}}
|
|
|
562 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
563 |
|
|
|
564 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
565 |
\mode<presentation>{
|
|
29
|
566 |
\begin{frame}[t]
|
|
|
567 |
\frametitle{\begin{tabular}{@ {}c@ {}}Mobile OS\end{tabular}}
|
|
28
|
568 |
|
|
|
569 |
\begin{itemize}
|
|
29
|
570 |
\item iOS and Android solve the defence-in-depth problem by \alert{sandboxing} applications\bigskip
|
|
|
571 |
|
|
|
572 |
\item you as developer have to specify the resources an application needs
|
|
|
573 |
\item the OS provides a sandbox where access is restricted to only these resources
|
|
28
|
574 |
\end{itemize}
|
|
|
575 |
\end{frame}}
|
|
|
576 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
577 |
|
|
|
578 |
|
|
|
579 |
|
|
|
580 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
581 |
\mode<presentation>{
|
|
|
582 |
\begin{frame}[c]
|
|
29
|
583 |
\frametitle{\begin{tabular}{@ {}c@ {}}Security Theater\end{tabular}}
|
|
|
584 |
|
|
28
|
585 |
|
|
29
|
586 |
Security theater is the practice of investing in countermeasures intended to provide the
|
|
|
587 |
\underline{feeling} of improved security while doing little or nothing to actually achieve it.\hfill{}\textcolor{gray}{Bruce Schneier}
|
|
28
|
588 |
|
|
|
589 |
\end{frame}}
|
|
|
590 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
591 |
|
|
29
|
592 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
593 |
\mode<presentation>{
|
|
|
594 |
\begin{frame}[c]
|
|
|
595 |
\frametitle{\begin{tabular}{@ {}c@ {}}\end{tabular}}
|
|
|
596 |
|
|
|
597 |
|
|
|
598 |
Security theater is the practice of investing in countermeasures intended to provide the
|
|
|
599 |
\underline{feeling} of improved security while doing little or nothing to actually achieve it.\hfill{}\textcolor{gray}{Bruce Schneier}
|
|
|
600 |
|
|
|
601 |
\end{frame}}
|
|
|
602 |
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
|
|
|
603 |
|
|
|
604 |
|
|
|
605 |
From: Ross Anderson <Ross.Anderson@cl.cam.ac.uk>
|
|
|
606 |
Sender: cl-security-research-bounces@lists.cam.ac.uk
|
|
|
607 |
To: cl-security-research@lists.cam.ac.uk
|
|
|
608 |
Subject: Tip off
|
|
|
609 |
Date: Tue, 02 Oct 2012 13:12:50 +0100
|
|
|
610 |
|
|
|
611 |
I received the following tip off, and have removed the sender's
|
|
|
612 |
coordinates. I suspect it is one of many security vendors who
|
|
|
613 |
don't even get the basics right; if you ever go to the RSA
|
|
|
614 |
conference, there are a thousand such firms in the hall, each
|
|
|
615 |
with several eager but ignorant salesmen. A trying experience
|
|
|
616 |
|
|
|
617 |
Ross
|
|
|
618 |
|
|
28
|
619 |
|
|
|
620 |
\end{document}
|
|
|
621 |
|
|
|
622 |
%%% Local Variables:
|
|
|
623 |
%%% mode: latex
|
|
|
624 |
%%% TeX-master: t
|
|
|
625 |
%%% End:
|
|
|
626 |
|