diff -r cd8d18f7b7ac -r da5713bcdbb0 slides/slides11.tex --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/slides/slides11.tex Fri Dec 12 15:41:37 2014 +0000 @@ -0,0 +1,138 @@ +\documentclass[dvipsnames,14pt,t]{beamer} +\usepackage{../slides} +\usepackage{../langs} +\usepackage{../graphics} +\usepackage{../data} +\usepackage{../grammar} + +% beamer stuff +\renewcommand{\slidecaption}{APP 11, King's College London} +\newcommand{\bl}[1]{\textcolor{blue}{#1}} + +\begin{document} + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[t] +\frametitle{% + \begin{tabular}{@ {}c@ {}} + \\ + \LARGE Access Control and \\[-3mm] + \LARGE Privacy Policies (11)\\[-6mm] + \end{tabular}}\bigskip\bigskip\bigskip + + \normalsize + \begin{center} + \begin{tabular}{ll} + Email: & christian.urban at kcl.ac.uk\\ + Office: & S1.27 (1st floor Strand Building)\\ + Slides: & KEATS (also homework is there)\\ + \end{tabular} + \end{center} + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] + +\begin{itemize} +\item you can still send me your homework\bigskip +\item Unix AC question: use a terminal-based editor (vm, + vim)\bigskip +\item exams: 2 out of 3 questions, 5 or so subquestions + each, you can fill in your answers on the question sheet +\end{itemize} + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] +\frametitle{Interlock Protocol} + +The interlock protocol (``best bet'' against MITM): + +\begin{center} +\begin{tabular}{ll@{\hspace{2mm}}l} +1. & \bl{$A \to B :$} & \bl{$K^{pub}_A$}\\ +2. & \bl{$B \to A :$} & \bl{$K^{pub}_B$}\\ +3. & & \bl{$\{A,m\}_{K^{pub}_B} \;\mapsto\; H_1,H_2$}\\ + & & \bl{$\{B,m'\}_{K^{pub}_A} \;\mapsto\; M_1,M_2$}\\ +4. & \bl{$A \to B :$} & \bl{$H_1$}\\ +5. & \bl{$B \to A :$} & \bl{$\{H_1, M_1\}_{K^{pub}_A}$}\\ +6. & \bl{$A \to B :$} & \bl{$\{H_2, M_1\}_{K^{pub}_B}$}\\ +7. & \bl{$B \to A :$} & \bl{$M_2$} +\end{tabular} +\end{center}\pause + +\footnotesize +\bl{$m$} = How is your grandmother? \bl{$m'$} = How is the +weather today in London? + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] + +\begin{center} +\begin{tabular}{l@{\hspace{9mm}}l} +\begin{tabular}[t]{@{}l@{}} +\bl{$A \to C : K^{pub}_A$}\\ +\bl{$C \to B : K^{pub}_C$}\\ +\bl{$B \to C : K^{pub}_B$}\\ +\bl{$C \to A : K^{pub}_C$}\medskip\\ +\bl{$\{A,m\}_{K^{pub}_C} \;\mapsto\; H_1,H_2$}\\ +\bl{$\{B,n\}_{K^{pub}_C} \;\mapsto\; M_1,M_2$}\bigskip\\ +\bl{$\{C,a\}_{K^{pub}_B} \;\mapsto\; C_1,C_2$}\\ +\bl{$\{C,b\}_{K^{pub}_A} \;\mapsto\; D_1,D_2$} +\end{tabular} & +\begin{tabular}[t]{@{}l@{}} +\bl{$A \to C : H_1$}\\ +\bl{$C \to B : C_1$}\\ +\bl{$B \to C : \{C_1, M_1\}_{K^{pub}_C}$}\\ +\bl{$C \to A : \{H_1, D_1\}_{K^{pub}_A}$}\\ +\bl{$A \to C : \{H_2, D_1\}_{K^{pub}_C}$}\\ +\bl{$C \to B : \{C_2, M_1\}_{K^{pub}_B}$}\\ +\bl{$B \to C : M_2$}\\ +\bl{$C \to A : D_2$} +\end{tabular} +\end{tabular} +\end{center} + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] + +\begin{itemize} +\item you have to ask something that cannot imitated + (requires \bl{$A$} and \bl{$B$} know each other) +\item what happens if \bl{$m$} and \bl{$n$} are voice + messages?\bigskip + +\item the moral: establishing a secure connection from ``zero'' is +almost impossible---you need to rely on some established +trust\medskip + +\item that is why we rely on certificates, which however are +badly, badly realised (just today a POODLE attack against SSL) + +\end{itemize} + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + + + +\end{document} + + +%%% Local Variables: +%%% mode: latex +%%% TeX-master: t +%%% End: +