VSzA techblog

Because of a response I got to my post about using MS Word templates with LaTeX, documenting the way I've been generating presentation material for my talks since 2010 got its priority raised. Like I said in the aforementioned post, I prefer using LaTeX for typesetting, and it's the same for creating those frames that appear behind my back during talks.

For the first few talks, I used the default template, then I switched to the Warsaw theme, which I frequently encounter in the beamer-using subset of IT security presenters. In 2011, Lasky – the graphics genius around Silent Signal – designed a presentation template that I actually liked, so I started fiddling with beamer to adapt the new theme.

First, I created a file called s2beamer.sty with the usual header, and two lines that set a sensible base. I had to disable shadow, since it couldn't handle setting background images, as it assumed that the background was a solid color.

\ProvidesPackage{s2beamer}

\useinnertheme[shadow=false]{rounded}
\usecolortheme{whale}

The theme I used included a separate background image for the title slide, and another for the rest (the ones with actual content), so I defined a command to create a title slide, which sets the background before and after the first frame. I added newlines only for readability, they must be removed or commented in the .sty file.

\newcommand{\titleframe}{
    \usebackgroundtemplate{
        \includegraphics[width=\paperwidth,height=\paperheight]
            {img/titlebg.jpg}
    }
    \frame{\titlepage}
    \usebackgroundtemplate{
        \includegraphics[width=\paperwidth,height=\paperheight]
            {img/slidebg.jpg}
    }
}

After setting the background, the colors needed to be changed too. First, I set the color of the body text and structural elements (such as list bullets). The color of the frame titles was set to the same orangeish one.

\setbeamercolor{normal text}{fg=white}
\usecolortheme[RGB={239,73,35}]{structure}
\setbeamercolor{frametitle}{fg=structure, bg=}

The default list bullets are actual bullets, which looked bad on the background image, so I changed them to little arrows. Also, I hid the navigation controls (placed in the lower-right corner) since they conflicted with the footer of the theme, and most people doesn't even know what they're for.

\setbeamertemplate{items}[default]
\setbeamertemplate{navigation symbols}{}

URLs and code snippets are written using fixed-size fonts (as they should be), but I prefer using Inconsolata for this purpose, instead of the default.

\RequirePackage{inconsolata}

In case of code snippets, I prefer using the listings package, and I configured it to use such colors for syntax highlighting that go well with the theme (newline added in case of the last line for readability only).

\RequirePackage{listings}
\definecolor{s2}{RGB}{240, 56, 31}
\definecolor{s2y}{RGB}{255, 200, 143}
\lstset{basicstyle=\footnotesize\ttfamily, breaklines=true,
    tabsize=2, keywordstyle=\color{s2}, stringstyle=\color{s2y}}

Since I give talks both in English and Hungarian, I added the following expression to set the order of first and last name according to babel language set by the document. (The \hunnexlabel command is defined when the babel language is set to magyar.) It also turns the e-mail address into a hyperlink that launches the default e-mail client when clicked on.

\ifdefined\hunnewlabel
    \renewcommand{\name}{\lastname\ \firstname}
\else
    \renewcommand{\name}{\firstname\ \lastname}
\fi

\author{\name\\\texttt{\href{mailto:\email}{\email}}}

The above lines require the following commands in the document:

\renewcommand{\email}{vsza@silentsignal.hu}
\renewcommand{\firstname}{András}
\renewcommand{\lastname}{Veres-Szentkirályi}

With these all set, I can create presentation material that look awesome but are still generated from plain text, thus compatible with all sensible editors and SCMs. You can see the snippets above in action by taking a look at my Hacktivity 2012 slides (four of them are below this paragraph), and some of them in the ones I made for Hacktivity 2011.

After a successful penetration test, I wanted to publish a detailed writeup about it, but the template we use at the company that includes a logo and some text in the footer was created using Microsoft Word, and I prefer using LaTeX for typesetting. It would have been possible to recreate the template from scratch, but I preferred to do it quick and, as it turned out, not so dirty.

First, I saved a document written using the template from Word to PDF, opened it up in Inkscape and removed the body (e.g. everything except the header and the footer). Depending on the internals of the PDF saving mechanism, it might be necessary to use ungroup one or more times to avoid removing more than needed. After this simple editing, I saved the result as another PDF, called s2bg.pdf.

Next, I created a file named s2.sty with the following lines.

\ProvidesPackage{s2}

\RequirePackage[top=4cm, bottom=2.8cm, left=2.5cm, right=2.5cm]{geometry}
\RequirePackage{wallpaper}
\CenterWallPaper{1}{s2bg.pdf}

The first line sets the package name, while the next three adjust the margins (which I calculated by using the ones set in Word and some trial and error) and put the PDF saved in Inkscape to the background of every page. The wallpaper package is available in the texlive-latex-extra package on Debian systems.

As our company uses a specific shade of orange as a primary color, I also changed the \section command to use this color for section headings.

\RequirePackage{color}
\definecolor{s2col}{RGB}{240, 56, 31}

\makeatletter
\renewcommand{\section}{\@startsection{section}{1}{0mm}
{\baselineskip}%
{\baselineskip}{\normalfont\Large\sffamily\bfseries\color{s2col}}}%
\makeatother

Creating a package comes with the advantage, that only a single line needs to be added to a document to use all the formatting described above, just like with CSS. The following two documents only differ such that the one on the right has an extra \usepackage{s2} line in the header.

Two documents published with this technique (although written in Hungarian) can be downloaded: the aforementioned writeup about client-side attacks and another one about things we did in 2011.

I've always found hyperref one of the best features of LaTeX, and although it supported Unicode, certain accented characters (in my case, ő and ű) were treated abnormally in case of PDF metadata fields, such as author and title. I mostly ignored the issue and reworded the contents, until I met a situation, where changing the data was not an option. To illustrate the issue, the following example was saved as wrong.tex and got compiled with the pdflatex wrong.tex command.

\documentclass{report}

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage[unicode, pdftitle={Árvíztűrő tükörfúrógép}]{hyperref}

\begin{document}
foobar
\end{document}

The result could be checked with pdfinfo and was far from what I expected.

$ pdfinfo wrong.pdf | grep Title
Title:          Árvízt¶r® tükörfúrógép

I searched the web, and was disappointed at first, having found unsolved forum threads, such as one written by also a Hungarian. Finally, I opened up the TeX section of the Stack Exchange network, and started typing a title for my question. Based on this, the forum offered a number of probably related posts, and I browsed through them out of curiosity. As it turned out, the solution lied within a post about Polish characters in pdftitle, and in retrospect, it seems obvious – like any other great idea. As Schweinebacke writes, “The optional argument of \usepackage is read by the LaTeX kernel, so hyperref cannot change scanning of the argument”. The problem can be eliminated simply by moving the title setup into a separate \hypersetup command – and behold, the pilcrow and the registered sign is gone, as seen in the following example.

$ diff wrong.tex right.tex
5c5,6
< \usepackage[unicode, pdftitle={Árvíztűrő tükörfúrógép}]{hyperref}
---
> \usepackage[unicode]{hyperref}
> \hypersetup{pdftitle={Árvíztűrő tükörfúrógép}}
$ pdfinfo right.pdf | grep Title
Title:          Árvíztűrő tükörfúrógép