diff -r be35ff24cccc -r d1d07f05325a slides/slides04.tex --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/slides/slides04.tex Sun Sep 22 15:22:11 2013 +0100 @@ -0,0 +1,1014 @@ +\documentclass[dvipsnames,14pt,t]{beamer} +\usepackage{beamerthemeplainculight} +\usepackage[T1]{fontenc} +\usepackage[latin1]{inputenc} +\usepackage{mathpartir} +\usepackage[absolute,overlay]{textpos} +\usepackage{ifthen} +\usepackage{tikz} +\usepackage{pgf} +\usepackage{calc} +\usepackage{ulem} +\usepackage{courier} +\usepackage{listings} +\renewcommand{\uline}[1]{#1} +\usetikzlibrary{arrows} +\usetikzlibrary{automata} +\usetikzlibrary{shapes} +\usetikzlibrary{shadows} +\usetikzlibrary{positioning} +\usetikzlibrary{calc} +\usepackage{graphicx} + +\definecolor{javared}{rgb}{0.6,0,0} % for strings +\definecolor{javagreen}{rgb}{0.25,0.5,0.35} % comments +\definecolor{javapurple}{rgb}{0.5,0,0.35} % keywords +\definecolor{javadocblue}{rgb}{0.25,0.35,0.75} % javadoc + +\lstset{language=Java, + basicstyle=\ttfamily, + keywordstyle=\color{javapurple}\bfseries, + stringstyle=\color{javagreen}, + commentstyle=\color{javagreen}, + morecomment=[s][\color{javadocblue}]{/**}{*/}, + numbers=left, + numberstyle=\tiny\color{black}, + stepnumber=1, + numbersep=10pt, + tabsize=2, + showspaces=false, + showstringspaces=false} + +\lstdefinelanguage{scala}{ + morekeywords={abstract,case,catch,class,def,% + do,else,extends,false,final,finally,% + for,if,implicit,import,match,mixin,% + new,null,object,override,package,% + private,protected,requires,return,sealed,% + super,this,throw,trait,true,try,% + type,val,var,while,with,yield}, + otherkeywords={=>,<-,<\%,<:,>:,\#,@}, + sensitive=true, + morecomment=[l]{//}, + morecomment=[n]{/*}{*/}, + morestring=[b]", + morestring=[b]', + morestring=[b]""" +} + +\lstset{language=Scala, + basicstyle=\ttfamily, + keywordstyle=\color{javapurple}\bfseries, + stringstyle=\color{javagreen}, + commentstyle=\color{javagreen}, + morecomment=[s][\color{javadocblue}]{/**}{*/}, + numbers=left, + numberstyle=\tiny\color{black}, + stepnumber=1, + numbersep=10pt, + tabsize=2, + showspaces=false, + showstringspaces=false} + +% beamer stuff +\renewcommand{\slidecaption}{APP 04, King's College London, 16 October 2012} + + +\begin{document} + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}<1>[t] +\frametitle{% + \begin{tabular}{@ {}c@ {}} + \\ + \LARGE Access Control and \\[-3mm] + \LARGE Privacy Policies (4)\\[-6mm] + \end{tabular}}\bigskip\bigskip\bigskip + + %\begin{center} + %\includegraphics[scale=1.3]{pics/barrier.jpg} + %\end{center} + +\normalsize + \begin{center} + \begin{tabular}{ll} + Email: & christian.urban at kcl.ac.uk\\ + Of$\!$fice: & S1.27 (1st floor Strand Building)\\ + Slides: & KEATS (also homework is there)\\ + \end{tabular} + \end{center} + + +\end{frame}} + %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{Unix-Style Access Control} + +\begin{itemize} +\item Q: ``I am using Windows. Why should I care?'' \\ A: In Windows you have similar AC: + +\begin{center} +\begin{tabular}{l} +administrators group\\ +\hspace{5mm}(has complete control over the machine)\\ +authenticated users\\ +server operators\\ +power users\\ +network configuration operators\\ +\end{tabular} +\end{center}\medskip + +\item Modern versions of Windows have more fine-grained AC than Unix; they do not have a setuid bit, but +have \texttt{runas} (asks for a password).\pause + +\item OS-provided access control can \alert{\bf add} to your +security. +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{c}Network Applications:\\[-1mm] Privilege Separation\end{tabular}} + + +\begin{center} + \begin{tikzpicture}[scale=1] + + \draw[line width=1mm] (-.3, 0) rectangle (1.5,2); + \draw (4.7,1) node {Internet}; + \draw (-2.7,1.7) node {\footnotesize Application}; + \draw (0.6,1.7) node {\footnotesize Interface}; + \draw (0.6,-0.4) node {\footnotesize \begin{tabular}{c}unprivileged\\[-1mm] process\end{tabular}}; + \draw (-2.7,-0.4) node {\footnotesize \begin{tabular}{c}privileged\\[-1mm] process\end{tabular}}; + + \draw[line width=1mm] (-1.8, 0) rectangle (-3.6,2); + + \draw[white] (1.7,1) node (X) {}; + \draw[white] (3.7,1) node (Y) {}; + \draw[red, <->, line width = 2mm] (X) -- (Y); + + \draw[red, <->, line width = 1mm] (-0.6,1) -- (-1.6,1); + \end{tikzpicture} +\end{center} + +\begin{itemize} +\item the idea is make the attack surface smaller and +mitigate the consequences of an attack +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{Shared Access Control} + +\begin{center} +\includegraphics[scale=0.7]{pics/pointsplane.jpg} +\end{center} + +\begin{textblock}{11}(10.5,10.5) +\small +To take an action you\\[-1mm] +need at least either: +\begin{itemize} +\item 1 CEO\\[-5mm] +\item 2 MDs, or\\[-5mm] +\item 3 Ds +\end{itemize} +\end{textblock} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{Lessons from Access Control} + +Not just restricted to Unix: + +\begin{itemize} +\item if you have too many roles (i.e.~too finegrained AC), then + hierarchy is too complex\\ + \textcolor{gray}{you invite situations like\ldots let's be root}\bigskip + +\item you can still abuse the system\ldots + +\end{itemize} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}A ``Cron''-Attack\end{tabular}} + +The idea is to trick a privileged person to do something on your behalf: + +\begin{itemize} +\item root:\\\texttt{rm /tmp/*/*}\bigskip\bigskip\pause + +\footnotesize +\begin{minipage}{1.1\textwidth} +\textcolor{gray}{the shell behind the scenes:}\\ +\textcolor{gray}{\texttt{rm /tmp/dir$_1$/file$_1$ /tmp/dir$_1$/file$_2$ /tmp/dir$_2$/file$_1$ \ldots}}\bigskip\\ + +\textcolor{gray}{this takes time} +\end{minipage} +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}A ``Cron''-Attack\end{tabular}} + +\begin{enumerate} +\item attacker \textcolor{gray}{(creates a fake passwd file)}\\ +\texttt{mkdir /tmp/a; cat > /tmp/a/passwd}\medskip +\item root \textcolor{gray}{(does the daily cleaning)}\\ +\texttt{rm /tmp/*/*}\medskip\\ +\hspace{2cm}\textcolor{gray}{\small records that \texttt{/tmp/a/passwd}}\\ +\hspace{2cm}\textcolor{gray}{\small should be deleted, but does not do it yet}\medskip\\ + +\item attacker \textcolor{gray}{(meanwhile deletes the fake passwd file, and establishes a link to +the real passwd file)}\\ +\texttt{rm /tmp/a/passwd; rmdir /tmp/a;}\\\texttt{ln -s /etc /tmp/a}\\ +\item root now deletes the real passwd file +\end{enumerate} + +\only<2>{ +\begin{textblock}{11}(2,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] +{\normalsize\color{darkgray} +\begin{minipage}{9cm}\raggedright +To prevent this kind of attack, you need additional +policies (don't do such operations as root). +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Schneier Analysis\end{tabular}} + +\textcolor{gray}{There is no absolutely secure system and security almost never comes for free.} + +\begin{itemize} +\item What assets are you trying to protect? +\item What are the risks to these assets? +\item How well does the security solution mitigate those risks? +\item What other risks does the security solution cause? +\item What costs and trade-offs does the security solution impose? +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Example: Credit Cards\end{tabular}} + +You might have the policy of not typing in your credit card online. Worthwhile or not? +\begin{itemize} +\item<2->What assets are you trying to protect?\\ +\only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}your credit card number\end{tabular}} +\item<3->What are the risks to these assets?\\ +\only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +With credit cards you loose a fixed amount \pounds{50}. Amazon \pounds{50}. \end{tabular}} +\item<4->How well does the security solution mitigate those risks?\\ +\only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Well, hackers steal credit cards from databases. They usually do not attack you individually.\end{tabular}} +\item<5->What other risks does the security solution cause? +\only<5>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright None (?)\end{tabular}} +\item<6->What costs and trade-offs does the security solution impose? +\only<6>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Internet shopping is convenient and sometimes cheaper.\end{tabular}} +\item<7>[]{\bf\large No!} +\end{itemize}\pause\pause + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Example: Firewalls\end{tabular}} + +\begin{center} +\includegraphics[scale=0.5]{pics/firewall.png} +\end{center} + +A firewall is a piece of software that controls incoming and outgoing traffic according to some rules. +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Example: Firewalls\end{tabular}} + +\begin{itemize} +\item<1->What assets are you trying to protect?\\ +\only<1>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}Whatever is behind the firewall +(credit cards, passwords, blueprints, \ldots)\end{tabular}} +\item<2->What are the risks to these assets?\\ +\only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +With a small online shop you are already at risk. Pentagon, definitely.\end{tabular}} +\item<3->How well does the security solution mitigate those risks?\\ +\only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Well, at home so not much. Everywhere else, if properly configurated then it does.\end{tabular}} +\item<4->What other risks does the security solution cause? +\only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright There might be backdoors or bugs in the firewall, +but generally they are secure. You choose to prevent certain traffic.\end{tabular}} +\item<5->What costs and trade-offs does the security solution impose? +\only<5>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Minimal to modest. Firewalls are part of free software. You need a knowledgeable +person to set them up.\end{tabular}} +\item<7>[]{\bf\large Yes!} +\end{itemize}\pause\pause + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Ex: Two-Factor Authentication\end{tabular}} + +Google uses nowadays two-factor authentication. But it is an old(er) +idea. It is used for example in Germany and Netherlands for online transactions. + +\begin{center} +\includegraphics[scale=0.6]{pics/tan1.jpg}\hspace{5mm} +\includegraphics[scale=0.2]{pics/tan2.jpg} +\end{center} + +\pause +Or nowadays by SMS (restricts the validity of the numbers) or with a secure generator + +\begin{center} +\includegraphics[scale=0.08]{pics/pinsentry.jpg} +\end{center} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Ex: Two-Factor Authentication\end{tabular}} + +\begin{itemize} +\item<1->What assets are you trying to protect?\\ +\only<1>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}Your bank account.\end{tabular}} +\item<2->What are the risks to these assets?\\ +\only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Nowadays pretty high risk.\end{tabular}} +\item<3->How well does the security solution mitigate those risks?\\ +\only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +It prevents problems when passwords are stolen. Man-in-the-middle attacks +still possible.\end{tabular}} +\item<4->What other risks does the security solution cause? +\only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Your mobile phone or credit card/pin might +be stolen. SIM card becomes more valuable.\end{tabular}} +\item<5->What costs and trade-offs does the security solution impose? +\only<5>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Banks need to establish an infrastructure. For you it might be inconvenient.\end{tabular}} +\item<7>[]{\bf\large Yes!} +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Security Seals\end{tabular}} + +According to Ross Anderson: ``\ldots is a tamper-indicating device +designed to leave non-erasable, unambiguous evidence of unauthorized +entry or tampering.'' + +\begin{center} +\includegraphics[scale=0.45]{pics/seal.jpg} +\end{center}\mbox{}\\[-12mm] + +They also need some quite sophisticated policies (seal regiment). +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Security Seals (2)\end{tabular}} + +\begin{itemize} +\item at the Argonne National Laboratory they tested 244 different security seals +\begin{itemize} +\item meantime to break the seals for a trained person: 100 s +\item including 19\% that were used for safeguard of nuclear material +\end{itemize}\bigskip + +\item Andrew Appel defeated all security seals which were supposed to keep +voting machines safe +\end{itemize} + + +\only<2>{ +\begin{textblock}{11}(1,1) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] +{\normalsize +\begin{minipage}{11cm}\raggedright\small +\begin{center} +\includegraphics[scale=0.25]{pics/appelseals.jpg} +\end{center} +\begin{center} +\begin{minipage}{10.5cm} +\begin{itemize} +\item The tamper-indicating tape can be lifted using a heat gun. +\item The security screw cap can be removed using a screwdriver, then the +serial-numbered top can be replaced (undamaged) onto a fresh (unnumbered) base. +\item The wire seal can be defeated using a \#4 wood screw. +\item The plastic strap seal can be picked using a jeweler's screwdriver. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Example: Security Seals\end{tabular}} + +\begin{itemize} +\item<1->What assets are you trying to protect?\\ +\only<1>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}Voting machines, doors.\end{tabular}} +\item<2->What are the risks to these assets?\\ +\only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright Casual thieves, insider attacks.\end{tabular}} +\item<3->How well does the security solution mitigate those risks?\\ +\only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Needs a quite complicated security regiment.\end{tabular}} +\item<4->What other risks does the security solution cause? +\only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright You might not notice tampering.\end{tabular}} +\item<5->What costs and trade-offs does the security solution impose? +\only<5>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +The ``hardware'' is cheap, but indirect costs can be quite high.\end{tabular}} +\item<7>[]{\bf\large No!} {\textcolor{gray}{Though in some areas they work: airports, swimming pools, \ldots}} +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Ex: Security-by-Obscurity\end{tabular}} + +You might think it is a good idea to keep a security relevant algorithm or +software secret. + +\begin{itemize} +\item<1->What assets are you trying to protect?\\ +\only<1>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}Source code, an algorithm and things that depend on it\end{tabular}} +\item<2->What are the risks to these assets?\\ +\only<2>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Can be pretty high (Oystercards).\end{tabular}} +\item<3->How well does the security solution mitigate those risks?\\ +\only<3>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright +Not really. The source code can be reverse engineered, stolen, coerced \ldots{}\end{tabular}} +\item<4->What other risks does the security solution cause? +\only<4>{\begin{tabular}{@{\hspace{1cm}}p{9cm}}\raggedright You prevent +scrutiny and independent advice. You also more likely than not to +get it wrong.\end{tabular}} +\item<5>[]{\bf\large No!} +\end{itemize} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Voting as Security Problem\end{tabular}} + +What are the security requirements of a voting system?\bigskip + +\begin{itemize} +\item<2->Integrity +\item<3->Ballot Secrecy +\item<5->Voter Authentication +\item<6->Enfranchisement +\item<7->Availability +\end{itemize} + +\only<2>{ +\begin{textblock}{5.5}(8,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] +{\small +\begin{minipage}{5cm}\raggedright +\begin{center} +\begin{minipage}{4.5cm} +\begin{itemize} +\item The outcome matches with the voters' intend. +\item There might be gigantic sums at stake and need to be defended against. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\only<4>{ +\begin{textblock}{5.5}(8,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] +{\small +\begin{minipage}{5cm}\raggedright +\begin{center} +\begin{minipage}{4.5cm} +\begin{itemize} +\item Nobody can find out how you voted. +\item (Stronger) Even if you try, you cannot prove how you voted. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\only<5>{ +\begin{textblock}{5.5}(8,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] +{\small +\begin{minipage}{5cm}\raggedright +\begin{center} +\begin{minipage}{4.5cm} +\begin{itemize} +\item Only authorised voters can vote up to the permitted number of votes. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\only<6>{ +\begin{textblock}{5.5}(8,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] +{\small +\begin{minipage}{5cm}\raggedright +\begin{center} +\begin{minipage}{4.5cm} +\begin{itemize} +\item Authorised voters should have the opportunity to vote. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\only<7>{ +\begin{textblock}{5.5}(8,5) +\begin{tikzpicture} +\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm, text centered] +{\small +\begin{minipage}{5cm}\raggedright +\begin{center} +\begin{minipage}{4.5cm} +\begin{itemize} +\item The voting system should accept all authorised votes and produce results in a timely manner. +\end{itemize} +\end{minipage} +\end{center} +\end{minipage}}; +\end{tikzpicture} +\end{textblock}} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Ballot Boxes\end{tabular}} + + +\begin{center} +\includegraphics[scale=2.5]{pics/ballotbox.jpg} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Problems with Voting\end{tabular}} + + +\begin{center}\large +\begin{tabular}{rcl} +Integrity & vs. & Ballot Secrecy\bigskip\\ +Authentication & vs. &Enfranchisement +\end{tabular} +\end{center}\bigskip\bigskip\pause + +Further constraints: + +\begin{itemize} +\item costs +\item accessibility +\item convenience +\item intelligibility +\end{itemize} +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}E-Voting\end{tabular}} + + +\begin{itemize} +\item The Netherlands between 1997 - 2006 had electronic voting machines\\ +\textcolor{gray}{(hacktivists had found: they can be hacked and also emitted radio signals revealing how you voted)} + +\item Germany had used them in pilot studies\\ +\textcolor{gray}{(in 2007 a law suit has reached the highest court and it rejected electronic voting +on the grounds of not being understandable by the general public)} + +\item UK used optical scan voting systems in a few polls +\end{itemize} +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}E-Voting\end{tabular}} + +\mbox{}\\[-12mm] +\begin{itemize} +\item US used mechanical machines since the 30s, later punch cards, now DREs and +optical scan voting machines \textcolor{gray}{(fantastic ``ecosystem'' for study)} + +\item Estonia used in 2007 the Internet for national elections +\textcolor{gray}{(there were earlier pilot studies in other countries)} + +\item India uses e-voting devices since at least 2003\\ +\textcolor{gray}{(``keep-it-simple'' machines produced by a government owned company)} + +\item South Africa used software for its tallying in the 1993 elections (when Nelson Mandela was elected) +\textcolor{gray}{(they found the tallying software was rigged, but they were able to tally manually)} +\end{itemize} +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}A Brief History of Voting\end{tabular}} + + +\begin{itemize} +\item Athenians +\begin{itemize} +\item show of hands +\item ballots on pieces of pottery +\item different colours of stones +\item ``facebook''-like authorisation +\end{itemize}\bigskip + +\textcolor{gray}{problems with vote buying / no ballot privacy}\bigskip + + +\item French Revolution and the US Constitution got things ``started'' with +paper ballots (you first had to bring your own; later they were pre-printed by parties) +\end{itemize} +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Ballot Boxes\end{tabular}} + +Security policies involved with paper ballots: + +\begin{enumerate} +\item you need to check that the ballot box is empty at the start of the poll / no false bottom (to prevent ballot stuffing) +\item you need to guard the ballot box during the poll until counting +\item tallied by a team at the end of the poll (independent observers) +\end{enumerate} + +\begin{center} +\includegraphics[scale=1.5]{pics/ballotbox.jpg} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Paper Ballots\end{tabular}} + +What can go wrong with paper ballots? + +\only<2>{ +\begin{center} +\includegraphics[scale=0.8]{pics/tweet.jpg}\\ +\footnotesize William M.~Tweed, US Politician in 1860's\\ +``As long as I count the votes, what are you going to do about it?'' +\end{center}} + +\only<3>{ +\medskip +\begin{center} +\begin{minipage}{10cm} +{\bf Chain Voting Attack} +\begin{enumerate} +\item you obtain a blank ballot and fill it out as you want +\item you give it to a voter outside the polling station +\item voter receives a new blank ballot +\item voter submits prefilled ballot +\item voter gives blank ballot to you, you give money +\item goto 1 +\end{enumerate} +\end{minipage} +\end{center} +} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Mechanical Voting Machines\end{tabular}} + +\begin{itemize} +\item<1-> Lever Voting Machines (ca.~1930 - 1990) +\only<1>{ +\begin{center} +\includegraphics[scale=0.56]{pics/leavermachine.jpg} +\end{center} +} +\item<2->Punch Cards (ca.~1950 - 2000) +\only<2>{ +\begin{center} +\includegraphics[scale=0.5]{pics/punchcard1.jpg}\;\; +\includegraphics[scale=0.46]{pics/punchcard2.jpg} +\end{center} +} +\end{itemize} + + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[t] +\frametitle{\begin{tabular}{@ {}c@ {}}Electronic Voting Machines\end{tabular}} + +\begin{center} +\begin{tabular}{c} +\includegraphics[scale=0.45]{pics/dre1.jpg}\; +\includegraphics[scale=0.40]{pics/dre2.jpg}\\\hline\\ +\includegraphics[scale=0.5]{pics/opticalscan.jpg} +\end{tabular} +\end{center} + +\only<1->{ +\begin{textblock}{5.5}(1,4) +DREs +\end{textblock}} +\only<1->{ +\begin{textblock}{5.5}(1,11) +Optical Scan +\end{textblock}} + +\only<2>{ +\begin{textblock}{5.5}(0.5,14.5) +all are computers +\end{textblock}} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}DREs\end{tabular}} + +Direct-recording electronic voting machines\\ +(votes are recorded for example memory cards) + +typically touchscreen machines + +usually no papertrail (hard to add: ballot secrecy) + +\begin{center} +\includegraphics[scale=0.56]{pics/dre1.jpg} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Diebold Machines\end{tabular}} + +The work by J.~Alex Halderman: + +\begin{itemize} +\item acquired a machine from an anonymous source\medskip +\item the source code running the machine was tried to keep secret\medskip\pause + +\item first reversed-engineered the machine (extremely tedious) +\item could completely reboot the machine and even install a virus that infects other Diebold machines +\item obtained also the source code for other machines +\end{itemize} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Diebold Machines\end{tabular}} + +What could go wrong?\pause \;\;Failure-in-depth.\bigskip\pause + +A non-obvious problem: + +\begin{itemize} +\item you can nowadays get old machines, which still store old polls + +\item the paper ballot box needed to be secured during the voting until counting; +e-voting machines need to be secured during the entire life-time +\end{itemize} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Paper Trail\end{tabular}} + +Conclusion:\\ Any electronic solution should have a paper trail. + +\begin{center} +\begin{tabular}{c} +\includegraphics[scale=0.5]{pics/opticalscan.jpg} +\end{tabular} +\end{center}\pause + +You still have to solve problems about +Voter registration, voter authentification, guarding against tampering + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}E-Voting in India\end{tabular}} + +Their underlying engineering principle is ``keep-it-simple'': + +\begin{center} +\begin{tabular}{c} +\includegraphics[scale=1.05]{pics/indiaellection.jpg}\;\; +\includegraphics[scale=0.40]{pics/india1.jpg} +\end{tabular} +\end{center}\medskip\pause + +Official claims: ``perfect'', ``tamperproof'', ``no need for technical improvements'' , ``infallible'' +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] +\frametitle{\begin{tabular}{@ {}c@ {}}Lessons to be Learned\end{tabular}} + +\begin{itemize} +\item keep a paper trail and design your system to keep this secure\medskip +\item make the software open source (avoid security-by-obscurity))\medskip +\item have a simple design in order to minimise the attack surface +\end{itemize} + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] + +\begin{center} +\includegraphics[scale=0.56]{pics/Voting1.png} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] + +\begin{center} +\includegraphics[scale=0.56]{pics/Voting2.png} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] + +\begin{center} +\includegraphics[scale=0.56]{pics/Voting3.png} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\mode{ +\begin{frame}[c] + +\begin{center} +\includegraphics[scale=0.56]{pics/Voting4.png} +\end{center} + + +\end{frame}} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +\end{document} + +%%% Local Variables: +%%% mode: latex +%%% TeX-master: t +%%% End: +