
diff -r 7dd5797a5ffa -r 470922b46a63 slides/slides10.tex
--- a/slides/slides10.tex	Fri Nov 28 13:47:32 2014 +0000
+++ b/slides/slides10.tex	Wed Dec 03 00:00:36 2014 +0000
@@ -1,27 +1,9 @@
 \documentclass[dvipsnames,14pt,t]{beamer}
-\usepackage{beamerthemeplaincu}
-\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}
-\usetikzlibrary{plotmarks}
-\usepackage{graphicx} 
-\usepackage{pgfplots}
-\usepackage{soul}
+\usepackage{../slides}
 \usepackage{../langs}
 \usepackage{../data}
-
+\usepackage{../graphics}
+\usepackage{soul}
 
 \tikzset{onslide/.code args={<#1>#2}{%
   \only<#1>{\pgfkeysalso{#2}} % \pgfkeysalso doesn't change the path
@@ -49,16 +31,15 @@
 \makeatother
 
 
-% beamer stuff 
-\renewcommand{\slidecaption}{AFL 10, King's College London, 4.~December 2013}
+% beamer stuff
+\renewcommand{\slidecaption}{AFL 10, King's College London}
 \newcommand{\bl}[1]{\textcolor{blue}{#1}}       
-\newcommand{\dn}{\stackrel{\mbox{\scriptsize def}}{=}}% for definitions
+
 
 \begin{document}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}<1>[t]
+\begin{frame}[t]
 \frametitle{%
   \begin{tabular}{@ {}c@ {}}
   \\[-3mm]
@@ -75,572 +56,31 @@
   \end{tabular}
   \end{center}
 
-\end{frame}}
+\end{frame}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \mode<presentation>{
 \begin{frame}[c]
 
-\Large\bf
-There are more problems, than there are programs.\bigskip\bigskip\pause\\
-
-There must be a problem for which there is no program.
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[t]
-\frametitle{Last Week}
-
-\begin{center}
-if \bl{$\varnothing$} does not occur in \bl{$r$} \;\;then\;\;\bl{$L(r) \not= \{\}$}
-\end{center}
-
-\noindent
-holds, or equivalently
-
-\begin{center}
-\bl{$L(r) = \{\}$} \;\;implies\;\; \bl{$\varnothing$} occurs in \bl{$r$}.\pause
-\end{center}
-
-\begin{center}
-\bl{\begin{tabular}{@ {}l@ {\hspace{2mm}}c@ {\hspace{2mm}}l@ {}}
-$occurs(\varnothing)$      & $\dn$ & $true$\\
-$occurs(\epsilon)$           & $\dn$ &  $f\!alse$\\
-$occurs (c)$                    & $\dn$ &  $f\!alse$\\
-$occurs (r_1 + r_2)$       & $\dn$ &  $occurs(r_1) \vee occurs(r_2)$\\ 
-$occurs (r_1 \cdot r_2)$ & $\dn$ &  $occurs(r_1) \vee occurs(r_2)$\\
-$occurs (r^*)$                & $\dn$ & $occurs(r)$ \\
-\end{tabular}}
-\end{center}
+\large\bf
+Using a compiler, \\how can you mount the\\ perfect attack against a system?
 
 \end{frame}}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c,fragile]
-\frametitle{Functional Programming}
-
-\footnotesize
-\begin{textblock}{13}(0.9,3)
-\lstset{emph={def,if,then,else},emphstyle=\color{javapurple}}
-\begin{lstlisting}[basicstyle=\ttfamily, numbers=none]
-def fib(n) = if n == 0 then 0 
-             else if n == 1 then 1 
-             else fib(n - 1) + fib(n - 2);
-
-def fact(n) = if n == 0 then 1 else n * fact(n - 1);
-
-def ack(m, n) = if m == 0 then n + 1
-                else if n == 0 then ack(m - 1, 1)
-                else ack(m - 1, ack(m, n - 1));
-                
-def gcd(a, b) = if b == 0 then a else gcd(b, a % b);                
-\end{lstlisting}
-\end{textblock}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \mode<presentation>{
 \begin{frame}[c]
 
-\begin{center}
-\bl{\begin{tabular}{@{}lcl@{}}
-\textit{Exp} & $\rightarrow$ &  \textit{Var} $|$ \textit{Num}\\
-              & $|$ & \textit{Exp} \texttt{+} \textit{Exp} $|$ ... $|$ ( \textit{Exp} )\\
-              & $|$ & \texttt{if}\; \textit{BExp} \;\texttt{then}\; \textit{Exp} \;\texttt{else}\; \textit{Exp}\\
-              & $|$ & \texttt{write}\;\textit{Exp}\\
-              & $|$ & \textit{Exp}\;\texttt{;}\;\textit{Exp}\\
-              & $|$ & \textit{FunName} \texttt{(}\textit{Exp},...,\textit{Exp}\texttt{)}\medskip\\
-\textit{BExp} & $\rightarrow$ & \ldots\medskip\\
-\textit{Decl} & $\rightarrow$ &  \textit{Def} \;\texttt{;}\; \textit{Decl}\\
-              & $|$ & \textit{Exp}\medskip\\
-\textit{Def} & 
-$\rightarrow$ &  \texttt{def} \textit{FunName}\texttt{(}\textit{x}$_1$,..., \textit{x}$_n$\texttt{)} \texttt{=} \textit{Exp}\\
-\end{tabular}}
-\end{center}
-
-
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Abstract Syntax Tree}
-
-\footnotesize
-\begin{textblock}{13}(0.3,2)
-\begin{lstlisting}[language=Scala,basicstyle=\ttfamily, numbers=none]
-abstract class Exp
-abstract class BExp 
-abstract class Decl
-
-case class 
-  Def(name: String, args: List[String], body: Exp) 
-                                          extends Decl
-case class Main(e: Exp) extends Decl
-
-case class Call(name: String, args: List[Exp]) extends Exp
-case class If(a: BExp, e1: Exp, e2: Exp) extends Exp
-case class Write(e: Exp) extends Exp
-case class Var(s: String) extends Exp
-case class Num(i: Int) extends Exp
-case class Aop(o: String, a1: Exp, a2: Exp) extends Exp
-case class Sequ(e1: Exp, e2: Exp) extends Exp
-
-case class Bop(o: String, a1: Exp, a2: Exp) extends BExp
-\end{lstlisting}
-\end{textblock}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Mathematical Functions}
-
-Compilation of some mathematical functions:
-
-\begin{center}
-\begin{tabular}{lcl}
-\texttt{Aop("+", a1, a2)} & $\Rightarrow$ & \texttt{...iadd}\\
-\texttt{Aop("-", a1, a2)} & $\Rightarrow$ & \texttt{...isub}\\
-\texttt{Aop("*", a1, a2)} & $\Rightarrow$ & \texttt{...imul}\\
-\texttt{Aop("/", a1, a2)} & $\Rightarrow$ & \texttt{...idiv}\\
-\texttt{Aop("\%", a1, a2)} & $\Rightarrow$ & \texttt{...irem}\\
-\end{tabular}
-\end{center}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Boolean Expressions}
-
-Compilation of boolean expressions:
-
-\begin{center}
-\begin{tikzpicture}[node distance=2mm and 4mm,
- block/.style={rectangle, minimum size=1cm, draw=black, line width=1mm},
- point/.style={rectangle, inner sep=0mm, minimum size=0mm, fill=red},
- skip loop/.style={red, line width=1mm, to path={-- ++(0,-10mm) -| (\tikztotarget)}}]
-\node (A1) [point] {};
-\node (b) [block, right=of A1] {code of \bl{$b$}};
-\node (A2) [point, right=of b] {};
-\node (cs1) [block, right=of A2] {code of \bl{$cs_1$}};
-\node (A3) [point, right=of cs1] {};
-\node (cs2) [block, right=of A3] {code of \bl{$cs_2$}};
-\node (A4) [point, right=of cs2] {};
-
-\only<1>{
-\draw (A1) edge [->, red, line width=1mm] (b);
-\draw (b) edge [->, red, line width=1mm] (A2);
-\draw (A2) edge [skip loop] (A3);
-\draw (A3) edge [->, red, line width=1mm] (cs2);
-\draw (cs2) edge [->,red, line width=1mm] (A4);
-\node [below=of cs1] {\raisebox{-5mm}{\small{}conditional jump}};}
-\end{tikzpicture}
-\end{center}
-
-\begin{center}
-\begin{tabular}{lcl}
-\texttt{Bop("==", a1, a2)} & $\Rightarrow$ & \texttt{...if\_icmpne...}\\
-\texttt{Bop("!=", a1, a2)} & $\Rightarrow$ & \texttt{...if\_icmpeq...}\\
-\texttt{Bop("<", a1, a2)} & $\Rightarrow$ & \texttt{...if\_icmpge...}\\
-\texttt{Bop("<=", a1, a2)} & $\Rightarrow$ & \texttt{...if\_icmpgt...}\\
-\end{tabular}
-\end{center}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[t, fragile]
-\frametitle{Sequences}
-
-Compiling \texttt{arg1 ; arg2}:
-
-
-\begin{textblock}{7}(2,5)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-...arg1...
-pop
-...arg1...
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-  
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[t, fragile]
-\frametitle{Write}
-
-Compiling \texttt{write(arg)}:
-
-
-\begin{textblock}{7}(2,4)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-...arg...
-dup
-invokestatic XXX/XXX/write(I)V
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-
-
-\begin{textblock}{7}(2,8)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=Scala,basicstyle=\ttfamily, numbers=none]
-case Write(a1) => {
-    compile_exp(a1, env) ++
-    List("dup\n",
-         "invokestatic XXX/XXX/write(I)V\n")
-  }
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-  
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Functions}
-
-\begin{textblock}{7}(1,2)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-.method public static write(I)V 
-   .limit locals 5 
-   .limit stack 5 
-   iload 0 
-   getstatic java/lang/System/out Ljava/io/PrintStream; 
-   swap 
-   invokevirtual java/io/PrintStream/println(I)V 
-   return 
-.end method
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-
-\begin{textblock}{10}(1,9.8)
-\small We will need for definitions\\[-8mm]\mbox{}\footnotesize
-\begin{center}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-.method public static f (I...I)I
-  .limit locals ??
-  .limit stack ?? 
-  ??
-.end method
-\end{lstlisting}
-\end{center}
-\end{textblock}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Stack Estimation}
-\footnotesize
-\begin{center}
-\begin{lstlisting}[language=Scala,basicstyle=\ttfamily, numbers=none]
-def max_stack_exp(e: Exp): Int = e match {
-  case Call(_, args) => args.map(max_stack_exp).sum
-  case If(a, e1, e2) => max_stack_bexp(a) + 
-  	(List(max_stack_exp(e1), max_stack_exp(e1)).max)
-  case Write(e) => max_stack_exp(e) + 1
-  case Var(_) => 1
-  case Num(_) => 1
-  case Aop(_, a1, a2) => 
-  	max_stack_exp(a1) + max_stack_exp(a2)
-  case Sequ(e1, e2) => 
-  	List(max_stack_exp(e1), max_stack_exp(e2)).max
-}
-
-def max_stack_bexp(e: BExp): Int = e match {
-  case Bop(_, a1, a2) => 
-  	max_stack_exp(a1) + max_stack_exp(a2)
-}
-\end{lstlisting}
-\end{center}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[fragile]
-\frametitle{Successor}
+{\large\bf
+What is a \alert{perfect} attack?}\bigskip
 
-\begin{textblock}{7}(1,2.5)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-.method public static suc(I)I 
-.limit locals 1
-.limit stack
-  iload 0
-  ldc 1
-  iadd
-  ireturn
-.end method 
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-\begin{textblock}{7}(6,8)
-\begin{tikzpicture}\small
-\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] 
-{\begin{minipage}{5cm}
-\begin{lstlisting}[language=Lisp,basicstyle=\ttfamily, numbers=none]
-def suc(x) = x + 1;
-\end{lstlisting}
-\end{minipage}};
-\end{tikzpicture}
-\end{textblock}
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[fragile]
-\frametitle{Addition}
-
-\begin{textblock}{7}(1,1.5)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-.method public static add(II)I 
-.limit locals 2
-.limit stack 4
-  iload 0
-  ldc 0
-  if_icmpne If_else_2
-  iload 1
-  goto If_end_3
-If_else_2:
-  iload 0
-  ldc 1
-  isub
-  iload 1
-  invokestatic defs/defs/add(II)I
-  invokestatic defs/defs/suc(I)I
-If_end_3:
-  ireturn
-.end method
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-\begin{textblock}{7}(6,6.2)
-\begin{tikzpicture}\small
-\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] 
-{\begin{minipage}{7cm}
-\begin{lstlisting}[language=Lisp,basicstyle=\ttfamily, numbers=none]
-def add(x, y) = 
-    if x == 0 then y 
-    else suc(add(x - 1, y));
-\end{lstlisting}
-\end{minipage}};
-\end{tikzpicture}
-\end{textblock}
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[fragile]
-\frametitle{Factorial}
-
-\begin{textblock}{7}(1,1.5)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none]
-.method public static facT(II)I 
-.limit locals 2
-.limit stack 4
-  iload 0
-  ldc 0	
-  if_icmpne If_else_2
-  iload 1
-  goto If_end_3
-If_else_2:
-  iload 0
-  ldc 1
-  isub
-  iload 0
-  iload 1
-  imul
-  invokestatic fact/fact/facT(II)I
-If_end_3:
-  ireturn
-.end method 
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-\begin{textblock}{7}(6,7)
-\begin{tikzpicture}\small
-\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] 
-{\begin{minipage}{7cm}
-\begin{lstlisting}[language=Lisp,basicstyle=\ttfamily, numbers=none]
-def facT(n, acc) = 
-  if n == 0 then acc 
-  else facT(n - 1, n * acc);
-\end{lstlisting}
-\end{minipage}};
-\end{tikzpicture}
-\end{textblock}
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[fragile]
-%\frametitle{Factorial}
-
-\begin{textblock}{7}(1,-0.2)\footnotesize
-\begin{minipage}{6cm}
-\begin{lstlisting}[language=JVMIS,basicstyle=\ttfamily, numbers=none, escapeinside={(*@}{@*)}]
-.method public static facT(II)I 
-.limit locals 2
-.limit stack 4
-(*@\hl{facT\_Start:} @*)
-  iload 0
-  ldc 0
-  if_icmpne If_else_2
-  iload 1
-  goto If_end_3
-If_else_2:
-  iload 0
-  ldc 1
-  isub
-  iload 0
-  iload 1
-  imul
-  (*@\hl{istore 1} @*)
-  (*@\hl{istore 0} @*)
-  (*@\hl{goto facT\_Start} @*)
-If_end_3:
-  ireturn
-.end method 
-\end{lstlisting}
-\end{minipage}
-\end{textblock}
-
-\begin{textblock}{7}(6,7)
-\begin{tikzpicture}\small
-\draw (0,0) node[inner sep=2mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] 
-{\begin{minipage}{7cm}
-\begin{lstlisting}[language=Lisp,basicstyle=\ttfamily, numbers=none]
-def facT(n, acc) = 
-  if n == 0 then acc 
-  else facT(n - 1, n * acc);
-\end{lstlisting}
-\end{minipage}};
-\end{tikzpicture}
-\end{textblock}
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Tail Recursion}
-
-A call to \texttt{f(args)} is usually compiled as\medskip
-
-{\small\begin{lstlisting}[basicstyle=\ttfamily, numbers=none]
-  args onto stack
-  invokestatic  .../f 
-\end{lstlisting}}\pause
-
-
-A call is in tail position provided:\medskip
-
-{\small\begin{itemize}
-\item \texttt{if Bexp then \hl{Exp} else \hl{Exp}}
-\item \texttt{Exp ; \hl{Exp}}
-\item \texttt{Exp  op Exp}
-\end{itemize}}\medskip
-
-then a call \texttt{f(args)} can be compiled as\medskip\small
-
-\begin{lstlisting}[basicstyle=\ttfamily, numbers=none]
-  prepare environment
-  jump to start of function
-\end{lstlisting}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\begin{frame}[c, fragile]
-\frametitle{Tail Recursive Call}
-\footnotesize
-\begin{textblock}{13}(0.3,2)
-\begin{lstlisting}[language=Scala,basicstyle=\ttfamily, numbers=none]
-def compile_expT(a: Exp, env: Mem, name: String): Instrs = 
-  ...
-  case Call(n, args) => if (name == n) 
-  { 
-    val stores = args.zipWithIndex.map 
-       { case (x, y) => "istore " + y.toString + "\n" } 
-    args.flatMap(a => compile_expT(a, env, "")) ++
-    stores.reverse ++ 
-    List ("goto " + n + "_Start\n") 
-  } 
-  else 
-  {
-    val is = "I" * args.length
-    args.flatMap(a => compile_expT(a, env, "")) ++
-    List ("invokestatic XXX/XXX/" + n + "(" + is + ")I\n")
-  }
-\end{lstlisting}
-\end{textblock}
-
-\end{frame}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-
-\Large\bf
-There are more problems, than there are programs.\bigskip\bigskip\\
-There must be a problem for which there is no program.
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Subsets}
-
-\Large
-\bl{$A \subseteq B$} and \bl{$B \subseteq A$}\bigskip
-
-then \bl{$A = B$}
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Injective Function}
-
-\Large
-\bl{f} is an injective function iff \bigskip
-
-\bl{$\forall x y.\; f(x) = f(y) \Rightarrow x = y$}
+\begin{enumerate}
+\item you can potentially completely take over a target system
+\item your attack is (nearly) undetectable
+\item the victim has (almost) no chance to recover
+\end{enumerate}
 
 \end{frame}}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
@@ -648,144 +88,144 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \mode<presentation>{
 \begin{frame}[c]
-\frametitle{Cardinality}
+
 
-\Large
-\bl{$|A|$} $\dn$ ``how many elements''\bigskip\\
+  \begin{center}
+  \begin{tikzpicture}[scale=1]
+  
+  \onslide<1->{
+  \node (A) at (0,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=17mm] {};
+  \node [below right] at (A.north west) {\footnotesize\begin{tabular}{@{}l@{}}
+  \only<1,2>{clean}\only<3->{\alert{hacked}}\\compiler\end{tabular}};}
 
-\bl{$A \subseteq B  \Rightarrow |A| \leq |B|$}\bigskip\\\pause
-
-if there is an injective function \bl{$f: A \rightarrow B$} then \bl{$|A| \leq |B|$}\
 
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
+  \onslide<2->{
+  \node (B) at (-2,2)  [draw=black, rectangle, very thick, minimum height=10mm, minimum width=12mm] {};
+  \node [below right] at (B.north west) {\footnotesize\begin{tabular}{@{}l@{}}login\\(src)\end{tabular}};
+  
+  \node (C) at (2,2)  [draw=black, rectangle, very thick, minimum height=10mm, minimum width=12mm] {};
+  \node [below right] at (C.north west) {\footnotesize\begin{tabular}{@{}l@{}}login\\(bin)\end{tabular}};
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Natural Numbers}
+  \draw[->, line width=2mm] (B) -- (C);
+  }
+  
+ \onslide<3->{\node [above left=-1.5mm] at (C.south east) {\footnotesize \alert{$\blacksquare$}};}
 
-\Large
-\bl{$\mathbb{N}$} \bl{$\dn$} \bl{$\{0, 1, 2, 3, .......\}$}\bigskip\pause 
-
-\bl{$A$} is \alert{countable} iff \bl{$|A| \leq |\mathbb{N}|$}
+  \end{tikzpicture}
+  \end{center}
 
 \end{frame}}
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{First Question}
-
-\Large
-\bl{$|\mathbb{N} - \{0\}|   \;\;\;\alert{?}\;\;\;  |\mathbb{N}| $}\bigskip\bigskip 
-
-\normalsize
-\bl{$\geq$} or \bl{$\leq$} or \bl{$=$} 
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-
-\Large
-\bl{$|\mathbb{N} - \{0, 1\}|   \;\;\;\alert{?}\;\;\;  |\mathbb{N}| $}\bigskip\pause 
-
-\bl{$|\mathbb{N} - \mathbb{O}|   \;\;\;\alert{?}\;\;\;  |\mathbb{N}| $}\bigskip\bigskip
-
-\normalsize
-\bl{$\mathbb{O}$} $\dn$ odd numbers\quad   \bl{$\{1,3,5......\}$}\\ \pause
-\bl{$\mathbb{E}$} $\dn$ even numbers\quad   \bl{$\{0,2,4......\}$}\\
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 \mode<presentation>{
 \begin{frame}[c]
 
-\Large
-\bl{$|\mathbb{N} \cup \mathbb{-N}|   \;\;\;\alert{?}\;\;\;  |\mathbb{N}| $}\bigskip\bigskip
-
+  \begin{center}
+  \begin{tikzpicture}[scale=1]
+  
+  \onslide<1->{
+  \node (A) at (0,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (A.north west) {\small V0.01};
+  \node [below right] (A1) at (A.south west) {\small Scala};
+  \node [below right] (A1) at (A1.south west) {\small\textcolor{gray}{host language}};
+  \node [above right] at (A.north west) {my compiler (src)};}
 
-\normalsize
-\bl{$\mathbb{\phantom{-}N}$} $\dn$ positive numbers\quad   \bl{$\{0,1,2,3,......\}$}\\
-\bl{$\mathbb{-N}$} $\dn$ negative numbers\quad   \bl{$\{0,-1,-2,-3,......\}$}\\
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
+  \onslide<2->{
+  \node (B) at (1.8,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (B.north west) {\small V0.02};
+  \node [below right] at (B.south west) {\small Scala};
+  \node at (3,0) {\ldots};
+
+  \node (C) at (5,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (C.north west) {\small V1.00};
+  \node [below right] at (C.south west) {\small Scala};}
 
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-
-\Large
-\bl{$A$} is \alert{countable} if there exists an injective \bl{$f : A \rightarrow \mathbb{N}$}\bigskip
+  \onslide<3->{
+  \node (D) at (6.8,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (D.north west) {\small V1.00};
 
-\bl{$A$} is \alert{uncountable} if there does not exist an injective \bl{$f : A \rightarrow \mathbb{N}$}\bigskip\bigskip 
-
+  \node (E) at (6.8,2)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (E.north west) {\small V1.01};}
+  
+  \onslide<4->{
+  \node (F) at (8.6,0)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (F.north west) {\small V1.01};
 
-countable:  \bl{$|A| \leq |\mathbb{N}|$}\\
-uncountable:  \bl{$|A| > |\mathbb{N}|$}\pause\bigskip
-
-
-Does there exist such an \bl{$A$} ?
+  \node (G) at (8.6,2)  [draw=black, rectangle, very thick, minimum height=18mm, minimum width=14mm] {};
+  \node [below right] at (G.north west) {\small V1.02};
+  \node at (9.8,0) {\ldots};
+  \node at (9.8,2) {\ldots};
+  \node at (8,-2) {\textcolor{gray}{\begin{tabular}{@{}l@{}}no host language\\needed\end{tabular}}};
+  }
+  
+  \end{tikzpicture}
+  \end{center}
 
 \end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Halting Problem}
-
-\large
-Assume a program \bl{$H$} that decides for all programs \bl{$A$} and all 
-input data \bl{$D$} whether\bigskip
-
-\begin{itemize}
-\item \bl{$H(A, D) \dn 1$} iff \bl{$A(D)$} terminates
-\item \bl{$H(A, D) \dn 0$} otherwise
-\end{itemize}
-
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Halting Problem (2)}
-
-\large
-Given such a program \bl{$H$} define the following program \bl{$C$}:
-for all programs \bl{$A$}\bigskip
-
-\begin{itemize}
-\item \bl{$C(A) \dn 0$} iff \bl{$H(A, A) = 0$} 
-\item \bl{$C(A) \dn$ loops} otherwise
-\end{itemize}
-
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-\mode<presentation>{
-\begin{frame}[c]
-\frametitle{Contradiction}
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%   
 
 
-\bl{$H(C, C)$} is either \bl{$0$} or \bl{$1$}.
+  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+  \mode<presentation>{
+  \begin{frame}<1-3>
+  \frametitle{\LARGE\begin{tabular}{c}Hacking Compilers 
+  \end{tabular}}
+  
+  %Why is it so paramount to have a small trusted code base (TCB)?
+  \bigskip\bigskip
+
+  \begin{columns}
+  \begin{column}{2.7cm}
+  \begin{minipage}{2.5cm}%
+  \begin{tabular}{c@ {}}
+  \includegraphics[scale=0.2]{../pics/ken-thompson.jpg}\\[-1.8mm]
+  \footnotesize Ken Thompson\\[-1.8mm]
+  \footnotesize Turing Award, 1983\\
+  \end{tabular}
+  \end{minipage}
+  \end{column}
+  \begin{column}{9cm}
+  \begin{tabular}{l@ {\hspace{1mm}}p{8cm}}
+ 
+  & Ken Thompson showed how to hide a Trojan Horse in a 
+  compiler \textcolor{red}{without} leaving any traces in the source code.\\[2mm]
+  
+  & No amount of source level verification will protect 
+  you from such Thompson-hacks.\\[2mm]
 
-\begin{itemize}
-\item \bl{$H(C, C) = 1$} $\stackrel{\text{def}\,H}{\Rightarrow}$ \bl{$C(C)\downarrow$} $\stackrel{\text{def}\,C}{\Rightarrow}$ \bl{$H(C, C)=0$} 
-\item \bl{$H(C, C) = 0$} $\stackrel{\text{def}\,H}{\Rightarrow}$ \bl{$C(C)$} loops $\stackrel{\text{def}\,C}{\Rightarrow}$\\ 
-\hspace{7cm}\bl{$H(C, C)=1$} 
-\end{itemize}
+  & Therefore in safety-critical systems it is important to rely 
+  on only a very small TCB.
+  \end{tabular}
+  \end{column}
+  \end{columns}
 
-Contradiction in both cases. So \bl{$H$} cannot exist.
+  \only<2>{
+  \begin{textblock}{6}(4,2)
+  \begin{tikzpicture}
+  \draw (0,0) node[inner sep=3mm,fill=cream, ultra thick, draw=red, rounded corners=2mm] 
+  {\normalsize
+  \begin{minipage}{8cm}
+  \begin{quote}
+  \includegraphics[scale=0.05]{../pics/evil.png}
+  \begin{enumerate}
+  \item[1)] Assume you ship the compiler as binary and also with sources.
+  \item[2)] Make the compiler aware when it compiles itself.
+  \item[3)] Add the Trojan horse.
+  \item[4)] Compile.
+  \item[5)] Delete Trojan horse from the sources of the compiler.
+  \item[6)] Go on holiday for the rest of your life. ;o)\\[-7mm]\mbox{}
+  \end{enumerate}
+  \end{quote}
+  \end{minipage}};
+  \end{tikzpicture}
+  \end{textblock}}
 
-\end{frame}}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
+  \end{frame}}
+  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%     
+
+
 
 \end{document}
 




