diff -r 9a3aa8c39951 -r 56bc53ba7c5b slides/slides05.tex --- a/slides/slides05.tex Tue Oct 20 01:01:17 2015 +0100 +++ b/slides/slides05.tex Wed Oct 21 13:31:56 2015 +0100 @@ -39,6 +39,155 @@ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \begin{frame}[c] +\frametitle{Problems with Key Fobs} + +\begin{columns} +\begin{column}[T]{4cm} +\includegraphics[scale=0.4]{../pics/car-standard.jpg} +\end{column} + +\begin{column}[T]{6cm}\small +Circumventing the ignition protection: + +\begin{itemize} +\item either dismantling Megamos crypto, +\item or use the diagnostic port to program + blank keys +\end{itemize} + +\hspace{14mm} +\includegraphics[scale=0.16]{../pics/Dismantling_Megamos_Crypto.png} +\end{column} +\end{columns} + + + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] +\frametitle{Protocols} + +\begin{center} +\includegraphics[scale=0.11]{../pics/keyfob.jpg} +\quad +\includegraphics[scale=0.232]{../pics/starbucks.jpg} +\end{center} + +\begin{itemize} +\item The point is that we have no control over the network + +\item We want to avoid that a message exchange (a protocol) can +be attacked without detection +\end{itemize} + +\end{frame} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] +\frametitle{G20 Summit in 2009} + +\begin{center} +\includegraphics[scale=0.1]{../pics/snowden.jpg} +\end{center} + +\small +\begin{itemize} +\item Snowden documents reveal ``that during G20 + meetings\dots{}GCHQ used + `ground-breaking intelligence capabilities' to intercept + the communications of visiting delegations. This + included setting up internet cafes where they used an + email interception program and key-logging software to + spy on delegates' use of computers\ldots'' + +\item ``The G20 spying appears to have been organised for the + more mundane purpose of securing an advantage in + meetings.'' +\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} + +\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} +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +\begin{frame}[c] \frametitle{Protocols} Some examples where ``over-the-air'' protocols are used: