diff --git a/20231005/dbs-20231005.tex b/20231005/dbs-20231005.tex
index 5b64857b27588e345126f26e59112c77b54481eb..ff938d18847f7546ff553fd02616f792af56d5cf 100644
--- a/20231005/dbs-20231005.tex
+++ b/20231005/dbs-20231005.tex
@@ -1,4 +1,4 @@
-% dbs-20221005.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231005.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231012/dbs-20231012.tex b/20231012/dbs-20231012.tex
index 418fc515517c108340d21900905d52d2145a567e..0fd7a102e182b7ec95b4a8b2a7357ac4981d4a8d 100644
--- a/20231012/dbs-20231012.tex
+++ b/20231012/dbs-20231012.tex
@@ -1,4 +1,4 @@
-% dbs-20221012.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231012.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231019/dbs-20231019.tex b/20231019/dbs-20231019.tex
index e046e63c7f3719e64cf3f303acc1575f14244993..f2a6a6084fd057e3781a77565dcb5215b02b2e9d 100644
--- a/20231019/dbs-20231019.tex
+++ b/20231019/dbs-20231019.tex
@@ -1,4 +1,4 @@
-% dbs-20221019.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231019.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231026/dbs-20231026.tex b/20231026/dbs-20231026.tex
index 8f32b157297165f9708965f95172caa0ccd30833..a2e9c53a2bbd82270f0dabd22c4e7b4ae0055afb 100644
--- a/20231026/dbs-20231026.tex
+++ b/20231026/dbs-20231026.tex
@@ -1,4 +1,4 @@
-% dbs-20221026.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231026.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231102/dbs-20231102.tex b/20231102/dbs-20231102.tex
index 23f2fbec303b5a8f0b11468330fcf5703daab5e6..acb034d4eb3e3b364b3db77cfbac455c5e543907 100644
--- a/20231102/dbs-20231102.tex
+++ b/20231102/dbs-20231102.tex
@@ -1,4 +1,4 @@
-% dbs-20221102.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231102.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231109/dbs-20231109.tex b/20231109/dbs-20231109.tex
index 5371e3709b6355785b2a966aff8bf4820edce7c4..66a7231e499354aa2fa5cd0634bb10545c0275fd 100644
--- a/20231109/dbs-20231109.tex
+++ b/20231109/dbs-20231109.tex
@@ -1,4 +1,4 @@
-% dbs-20221109.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231109.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231116/dbs-20231116.tex b/20231116/dbs-20231116.tex
index 6a10877d712044c8cdb2c20d90b6514cedbac2aa..d56535d54f0cdaea0a3704dbb0cf0a2e9d5c259d 100644
--- a/20231116/dbs-20231116.tex
+++ b/20231116/dbs-20231116.tex
@@ -1,4 +1,4 @@
-% dbs-20221116.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231116.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231123/dbs-20231123.tex b/20231123/dbs-20231123.tex
index bf9e093389a18ed58763628c991b85746797b99d..bb810c3dfdd5b0285757cb5f84e9435f4bcab66c 100644
--- a/20231123/dbs-20231123.tex
+++ b/20231123/dbs-20231123.tex
@@ -1,4 +1,4 @@
-% dbs-20221123.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231123.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231130/dbs-20231130.tex b/20231130/dbs-20231130.tex
index 4a039d911b98ac1088d0707800db846ce3b97f45..e6f49ac93bc062553d06bdbbbb8bbb3ddc72d45e 100644
--- a/20231130/dbs-20231130.tex
+++ b/20231130/dbs-20231130.tex
@@ -1,4 +1,4 @@
-% dbs-20221130.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231130.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231207/dbs-20231207.tex b/20231207/dbs-20231207.tex
index 2296ae2843ec63b2d755855dbfda23f9323fc86b..d72d88d149d27843dfc1e3dcb24aa68999c0cc76 100644
--- a/20231207/dbs-20231207.tex
+++ b/20231207/dbs-20231207.tex
@@ -1,4 +1,4 @@
-% dbs-20221207.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231207.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
diff --git a/20231214/dbs-20231214.pdf b/20231214/dbs-20231214.pdf
index 39420b39457cf57c702e84338510468305a6980d..7a1b21a21f2b8ebb47b926d8e711373037804464 100644
Binary files a/20231214/dbs-20231214.pdf and b/20231214/dbs-20231214.pdf differ
diff --git a/20231214/dbs-20231214.tex b/20231214/dbs-20231214.tex
index 7198a1ee652368e02283dccb399c009eced16201..27d638b68501743d5ecedf1bda725370495131e7 100644
--- a/20231214/dbs-20231214.tex
+++ b/20231214/dbs-20231214.tex
@@ -1,4 +1,4 @@
-% dbs-20221214.pdf - Lecture Slides on Databases and Information Security
+% dbs-20231214.pdf - Lecture Slides on Databases and Information Security
% Copyright (C) 2023 Peter Gerwinski
%
% This document is free software: you can redistribute it and/or
@@ -20,7 +20,7 @@
% Attribution-ShareAlike 3.0 Unported License along with this
% document. If not, see <http://creativecommons.org/licenses/>.
-% README: @@@
+% README: GUI-Zugriff, SQL Injection
\documentclass[10pt,t]{beamer}
@@ -61,18 +61,19 @@
\color{medgreen}
\item[4.10] Funktionen und Trigger
\item[4.11] GUI-Zugriff
+ \color{orange}
\item[4.12] SQL Injection
- \color{red}
+ \color{black}
\item[4.13] Datensicherheit bei Datenbanken
\item[4.14] Sonstige Datenbanken
\end{itemize}
\item[\textbf{5}] \textbf{Kryptographie}
- \begin{itemize}
- \color{red}
- \item[5.1] Einführung
- \vspace*{-\smallskipamount}
- \item[\textbf{\dots}]
- \end{itemize}
+% \begin{itemize}
+% \color{red}
+% \item[5.1] Einführung
+% \vspace*{-\smallskipamount}
+% \item[\textbf{\dots}]
+% \end{itemize}
\vspace*{-\smallskipamount}
\item[\textbf{\dots}]
\end{itemize}
@@ -183,14 +184,18 @@
Bessere Lösung: \newterm{Prepared Statements}
\begin{itemize}
- \item
- \url{https://www.postgresql.org/docs/current/sql-prepare.html}
- \item
- \url{https://www.w3schools.com/php/php_mysql_prepared_statements.asp}
+ \arrowitem
+ nächstes Jahr
+% \item
+% \url{https://www.postgresql.org/docs/current/sql-prepare.html}
+% \item
+% \url{https://www.w3schools.com/php/php_mysql_prepared_statements.asp}
\end{itemize}
\end{frame}
+\iffalse
+
\subsection{Datensicherheit bei Datenbanken}
\begin{frame}
@@ -255,4 +260,6 @@
\end{frame}
+\fi
+
\end{document}
diff --git a/20240111/Zeichen_123.pdf b/20240111/Zeichen_123.pdf
new file mode 120000
index 0000000000000000000000000000000000000000..fdbc897227df059cfda790a16555e6e417682116
--- /dev/null
+++ b/20240111/Zeichen_123.pdf
@@ -0,0 +1 @@
+../common/Zeichen_123.pdf
\ No newline at end of file
diff --git a/20240111/dbs-20240111.pdf b/20240111/dbs-20240111.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..3f9616efe9f3278e1b8dc63ef26c0acb096a7d2f
Binary files /dev/null and b/20240111/dbs-20240111.pdf differ
diff --git a/20240111/dbs-20240111.tex b/20240111/dbs-20240111.tex
new file mode 100644
index 0000000000000000000000000000000000000000..af10b15c0bdd95c887d21b2596222a814a0fc91e
--- /dev/null
+++ b/20240111/dbs-20240111.tex
@@ -0,0 +1,438 @@
+% dbs-20240111.pdf - Lecture Slides on Databases and Information Security
+% Copyright (C) 2023, 2024 Peter Gerwinski
+%
+% This document is free software: you can redistribute it and/or
+% modify it either under the terms of the Creative Commons
+% Attribution-ShareAlike 3.0 License, or under the terms of the
+% GNU General Public License as published by the Free Software
+% Foundation, either version 3 of the License, or (at your option)
+% any later version.
+%
+% This document is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with this document. If not, see <http://www.gnu.org/licenses/>.
+%
+% You should have received a copy of the Creative Commons
+% Attribution-ShareAlike 3.0 Unported License along with this
+% document. If not, see <http://creativecommons.org/licenses/>.
+
+% README: Datensicherheit bei Datenbanken, sonstige Datenbanken, Kryptographie
+
+\documentclass[10pt,t]{beamer}
+
+\usepackage{pgslides}
+
+\newcommand{\vfilll}{\vspace{0pt plus 1filll}}
+
+\newcommand{\underconstruction}{%
+ \begin{picture}(0,0)
+ \put(11,1.2){\makebox(0,0)[b]{\includegraphics[width=1.5cm]{Zeichen_123.pdf}}}
+ \put(11,0.9){\makebox(0,0)[t]{\shortstack{Änderungen\\vorbehalten}}}
+ \end{picture}}
+
+\title{Datenbanken und Datensicherheit}
+\author{Prof.\ Dr.\ rer.\ nat.\ Peter Gerwinski}
+\date{11.\ Januar 2024}
+
+\begin{document}
+
+\maketitleframe
+
+\nosectionnonumber{\inserttitle}
+
+\begin{frame}
+
+ \shownosectionnonumber
+
+ \begin{itemize}
+ \item[\textbf{1}] \textbf{Einführung}
+ \hfill\makebox(0,0)[br]{\raisebox{2.25ex}{\url{https://gitlab.cvh-server.de/pgerwinski/dbs}}}%
+ \item[\textbf{2}] \textbf{Kurzeinführung Unix}
+ \item[\textbf{3}] \textbf{Kurzeinführung TCP/IP}
+ \item[\textbf{4}] \textbf{Relationale Datenbanken}
+ \begin{itemize}
+ \vspace*{-\smallskipamount}
+ \item[\textbf{\dots}]
+ \item[4.9] Indizierung
+ \color{medgreen}
+ \item[4.10] Funktionen und Trigger
+ \item[4.11] GUI-Zugriff
+ \color{orange}
+ \item[4.12] SQL Injection
+ \color{red}
+ \item[4.13] Datensicherheit bei Datenbanken
+ \item[4.14] Sonstige Datenbanken
+ \end{itemize}
+ \item[\textbf{5}] \textbf{Kryptographie}
+ \begin{itemize}
+ \color{red}
+ \item[5.1] Einführung
+ \vspace*{-\smallskipamount}
+ \item[\textbf{\dots}]
+ \end{itemize}
+ \vspace*{-\smallskipamount}
+ \item[\textbf{\dots}]
+ \end{itemize}
+
+ \vfilll
+ \underconstruction
+
+\end{frame}
+
+\setcounter{section}{3}
+\section{Relationale Datenbanken}
+\setcounter{subsection}{9}
+\subsection{Funktionen und Trigger}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ Funktionen:
+ \begin{itemize}
+ \item
+ \lstinline[style=cmd]{PROCEDURE} entspricht einer \lstinline{void}-Funktion in C.
+ \item
+ \url{https://www.postgresql.org/docs/15/sql-createprocedure.html}
+ \end{itemize}
+
+ \bigskip
+
+ Trigger:
+ \begin{itemize}
+ \item
+ \url{https://www.sqltutorial.org/sql-triggers/}
+ \item
+ \url{https://www.postgresqltutorial.com/postgresql-triggers/creating-first-trigger-postgresql/}
+ \end{itemize}
+
+\end{frame}
+
+\subsection{GUI-Zugriff}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ \begin{itemize}
+ \item
+ Anwendung nutzt DBMS-Client-Bibliothek\\
+ GUI-Programmierung: wie gewohnt
+ \item
+ Spezialfall: Web-Anwendung
+ \end{itemize}
+
+ \bigskip
+
+ Beispiel: Programmiersprache PHP
+ \begin{itemize}
+ \item
+ Integration in HTML-Quelltext: \lstinline{<?php ... ?>}
+ \item
+ Objekt zur Kommunikation mit Datenbanken: \lstinline{PDO}
+ \end{itemize}
+
+ \bigskip
+
+ Literatur:
+ \begin{itemize}
+ \item
+ \url{https://www.postgresqltutorial.com/postgresql-php/connect/}
+ \item
+ \url{https://www.phptutorial.net/php-pdo/pdo-connecting-to-postgresql/}
+ \end{itemize}
+
+\end{frame}
+
+\subsection{SQL Injection}
+
+\begin{frame}[fragile]
+
+ \showsection
+ \showsubsection
+
+ Problem:
+ \begin{itemize}
+ \item
+ Ein böswilliger Benutzer gibt über eine Benutzerschnittstelle
+ (z.\,B.\ ein Web-Interface) Daten ein (z.\,B.\ einen "`Namen"'),
+ die Sonderzeichen enthalten, damit sie als SQL-Befehle ausgeführt werden.
+ \item
+ Literatur: \url{https://xkcd.com/327/}
+ \end{itemize}
+
+ \medskip
+
+ Lösung: Die Benutzerschnittstelle prüft die Daten auf Sonderzeichen\\
+ und ersetzt diese durch geeignete Escape-Sequenzen
+ \begin{itemize}
+ \item
+ \lstinline[style=cmd]{'} durch \lstinline[style=cmd]{''} ersetzen
+ \item
+ Funktion \lstinline[style=cmd]{CHR()}
+ \item
+ Viele DBMS verstehen ein vorangestelltes \lstinline[style=cmd]{\}.
+ \end{itemize}
+
+ \medskip
+
+ Bessere Lösung: \newterm{Prepared Statements}
+ \begin{itemize}
+ \item
+ \url{https://www.postgresql.org/docs/current/sql-prepare.html}
+ \item
+ \url{https://www.w3schools.com/php/php_mysql_prepared_statements.asp}
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Datensicherheit bei Datenbanken}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ \begin{itemize}
+ \item
+ kein direkter Zugriff von außen auf die Datenbank
+ \item
+ feingranulare Benutzerrechte
+ \item
+ Software aktuell halten
+ \item
+ Prepared Statements
+ \item
+ Transportverschlüsselung
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Sonstige Datenbanken}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ \begin{itemize}
+ \item
+ Eingebettete Datenbanken:\\
+ Berkeley DB, SQLite\\
+ Software-Bibliothek, keine Client-Server-Struktur
+ \item
+ Nicht-relationale Datenbanken:\\
+ dokumentenorientierte Datenbanken, noSQL\\
+ Performanz wichtiger als Konsistenz\\
+ \textarrow\ Applikationen stärker in Konsistenzprüfung eingebunden
+ \end{itemize}
+
+\end{frame}
+
+\section{Kryptographie}
+\subsection{Einführung}
+
+\begin{frame}
+
+ \showsection
+ \showsubsection
+
+ \textbf{Was ist Datensicherheit?}
+
+ \smallskip
+
+ \begin{minipage}[t]{0.24\textwidth}
+ \begin{itemize}
+ \item[] \strut
+ \item Vertraulichkeit
+ \item Integrität\\\strut
+ \item Verfügbarkeit
+ \end{itemize}
+ \end{minipage}%
+ \begin{minipage}[t]{0.25\textwidth}
+ \begin{itemize}
+ \item[] (CIA)
+ \item[] (confidentiality)
+ \item[] (integrity)\\\strut
+ \item[] (availability)
+ \end{itemize}
+ \end{minipage}\quad
+ \begin{minipage}[t]{0.45\textwidth}
+ \begin{itemize}
+ \item[] \strut
+ \arrowitem {\only<2->{\color{red}}Verschlüsselung}
+ \arrowitem Konsistenzprüfungen,\\
+ Prüfwerte, {\only<2->{\color{red}}Signaturen}
+ \arrowitem Backups, Ausfallsicherheit
+ \end{itemize}
+ \end{minipage}
+
+ \bigskip
+
+ \begin{itemize}
+ \item
+ Identifizierbarkeit
+ (Authentizität, Nichtabstreitbarkeit, Zurechenbarkeit)\\
+ \textarrow\ {\only<2->{\color{red}}Passwörter},
+ {\only<2->{\color{red}}Signaturen}\\[\smallskipamount]
+ bzw.
+ \item
+ Anonymität
+ (plausible Abstreitbarkeit, Nichtzurechenbarkeit)\\
+ \textarrow\ Pseudonymisierung, Anonymisierung,\\
+ \phantom{\textarrow\ }{\only<2->{\color{red}}Verschlüsselung}, Steganographie
+ \pause\hfill\textcolor{red}{\textarrow\ Kryptographie}
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Symmetrische Verschlüsselung}
+
+\begin{frame}
+
+ \showsection
+
+ \textbf{Kryptographie}
+ \begin{itemize}
+ \item
+ Verschlüsselung: symmetrisch, asymmetrisch, hybrid
+ \item
+ Hashes: Einwegfunktionen, Salt
+ \item
+ Signaturen, Zertifikate
+ \item
+ Schlüsselaustausch
+ \end{itemize}
+
+ \bigskip
+
+ \showsubsection
+
+ \vspace{-\medskipamount}
+
+ \begin{itemize}
+ \item
+ Derselbe Schlüssel zum Ver- und Entschlüsseln
+ \item
+ Beispiele:
+ {\only<6->{\color{red}}Cäsar-Chiffre},
+ {\only<6->{\color{red}}Monoalphabetische Substitution}\pause,\\
+ One Time Pad\visible<4->{,}\\
+ \visible<4->{%
+ \only<5->{\emph{spezielle }}Pseudozufallszahlengenerator\only<5->{en},
+ Startwert als Schlüssel\only<5->{:}\\
+ \visible<5->{
+ {\only<6->{\color{red}}Enigma},
+ {\only<6->{\color{red}}DES},
+ {\only<6->{\color{orange}}3DES},
+ {\only<6->{\color{orange}}RC4},
+ IDEA,
+ Blowfish,
+ TwoFish,
+ CAST,
+ AES,
+ \dots
+ }
+ }
+ \pause
+ \item
+ Problem: Schlüsselaustausch
+ \pause[7]
+ \item
+ Lösung: \newterm{asymmetrische Verschlüsselung}
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Asymmetrische Verschlüsselung}
+
+\begin{frame}
+
+ \showsubsection
+
+ \vspace{-\medskipamount}
+
+ \begin{itemize}
+ \item
+ verschiedene Schlüssel zum Ver- und Entschlüsseln:\\
+ öffentlicher und privater Schlüssel
+ \item
+ Prinzip: mathematische Operation,\\
+ einfach durchzuführen, schwer rückgängig zu machen
+ \medskip
+ \item
+ Beispiel: $N = p \cdot q$ -- einfacher als Primfaktorzerlegung von $N$
+ \textarrow\ RSA\\[\smallskipamount]
+ $73 \cdot 97 = 7081$: geht notfalls noch im Kopf\\
+ Primfaktorzerlegung von $7081$: mindestens schriftlich, besser mit Rechner
+ \medskip
+ \item
+ Beispiel: $c = b^a$ -- einfacher als $a = \log_b c$
+ \textarrow\ Diffie-Hellman, ElGamal\\[\smallskipamount]
+ $7^5 = 16807$: geht notfalls noch im Kopf\\
+ $\log_7 16807$: mindestens schriftlich, besser mit Rechner
+ \medskip
+ \arrowitem
+ Details: Algorithmen und Datenstrukturen
+ \pause
+ \bigskip
+ \item
+ Nachteil: wesentlich aufwendiger und daher langsamer\\
+ als symmetrische Verschlüsselung
+ \arrowitem
+ \newterm{hybride Verschlüsselung}: nur Schlüsselaustausch asymmetrisch,\\
+ eigentliche Vrschlüsselung symmetrisch
+ \end{itemize}
+
+\end{frame}
+
+\subsection{Signaturen}
+
+\begin{frame}
+
+ \showsubsection
+
+ \vspace{-\medskipamount}
+
+ \begin{itemize}
+ \item
+ \newterm{kryptographische Hash-Funktion\/}:
+ leicht auszurechnen, schwer zu manipulieren
+ \item
+ asymmetrisch: \newterm{Signatur}\\
+ Hash-Wert mit privatem Schlüssel verschlüsseln,\\
+ mit öffentlichem Schlüssel entschlüsseln
+ \item
+ symmetrisch: \newterm{Message Authentication Code\/} (MAC)\\
+ z.\,B.\ Hash-Wert über Nachricht + geheimer Schlüssel
+ \end{itemize}
+
+ \pause
+ \bigskip
+
+ Angriffsmöglichkeit: \newterm{Man-in-the-middle\/}-Angriff\\
+ Beim Schlüsselaustausch anderen Schlüssel unterschieben\\
+ \textarrow\ Sorgfalt beim Schlüsselaustausch
+
+ \pause
+ \bigskip
+
+ \textbf{Praxis-Beispiele}
+ \begin{itemize}
+ \item
+ SSH
+ \item
+ HTTPS
+ \item
+ OpenPGP
+ \end{itemize}
+
+\end{frame}
+
+\end{document}
diff --git a/20240111/logo-hochschule-bochum-cvh-text-v2.pdf b/20240111/logo-hochschule-bochum-cvh-text-v2.pdf
new file mode 120000
index 0000000000000000000000000000000000000000..4aa99b8f81061aca6dcaf43eed2d9efef40555f8
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