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+\documentclass[aspectratio=169,11pt]{beamer}
+\usetheme{default}
+%\setbeamertemplate{frametitle}{}
+\newenvironment{myline}
+    %{\usebeamerfont{frametitle}\usebeamercolor[fg]{frametitle}\vfill\centering}
+    {\usebeamerfont{frametitle}\vfill\centering}
+    {\par\vfill}
+
+\usetheme{Warsaw}
+\usecolortheme{whale}
+
+\title{SIM card technology from A to Z}
+%\subtitle{Subtitle}
+\author{Harald~Welte}
+\date[Dec 2019, 36C3]{Chaos Communication Congress 2019}
+\institute{osmocom.org}
+
+
+\begin{document}
+
+\begin{frame}
+\titlepage
+\end{frame}
+
+
+\begin{frame}{Outline}
+	\tableofcontents[hideallsubsections]
+\end{frame}
+
+
+\begin{frame}{About the speaker}
+\begin{itemize}
+	\item Free Software + OSHW developer for more than 20 years
+	\item Used to work on the Linux kernel from 1999-2009
+	\item working with contact chip cards since ~1999, contactless since ~2006
+	\item developing FOSS in cellular communications (Osmocom) since ~2008
+	\begin{itemize}
+		\item developed various SIM card related tools in software an hardware
+	\end{itemize}
+	\item Living and working in Berlin, Germany.
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Relation of SIM card specifications}
+\includegraphics[width=150mm]{sim_card_specs.png}
+\end{frame}
+
+% from APDU to Z... ?
+
+\begin{frame}{The SIM: Subscriber Identity Module}
+\begin{itemize}
+	\item probably anyone in the audience has at least one, likely more
+	\item ubiquitous; every device withe cellular connectivity has at least one
+	\item not many people outside the telecom industry ever look at them in much detail
+	\item SIM card hacking (in the security sense) has a tradition at CCC since at least 1998
+	\begin{itemize}
+		\item Vodafone Germany SIM card cloning: https://ftp.ccc.de/software/gsm/gsm\_hack.tar.gz
+		\item SIM card simulator in Turbo C (1998): https://ftp.ccc.de/software/gsm/SIM\_sim.zip
+	\end{itemize}
+	\item meanwhile: SIM technology stack is getting more complex and deep
+	\item let's recap what SIM cards actually are, and what they do
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{Classic SIM in early GSM}
+\begin{itemize}
+	\item Idea of storing subscriber identity predates GSM (e.g. C-Netz since 1988)
+	% c-netz-karte.jpg
+	\item GSM from the very beginning introduces concept of SIM card
+	\item store subscriber identity outside of the phone
+	\item store some network related parameters
+	\begin{itemize}
+		\item static (like access control class)
+		\item dynamic (like TMSI, Kc, ...)
+	\end{itemize}
+	\item full credit card size so it can be used in radios installed in (rented, shared company) cars.
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{ISO 7816}
+\begin{itemize}
+	\item the {\em mother of all smart card} spec
+	\item "Integrated circuit(s) cards with contacts"
+	\item 15 parts, most relevant are below:
+	\begin{itemize}
+		\item Part 1: Physical characteristics
+		\item Part 2: Dimensions and location of the contacts
+		\item Part 3: Electronic signals and transmission protocols
+		\item Part 4: Interindustry commands for interchange
+		\begin{itemize}
+			\item Why not international inter-industry commands for interworking information interchange?  Anyone?
+		\end{itemize}
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{GSM TS 11.11}
+\begin{itemize}
+	\item {\em Specification of the Subscriber Identity Module - Mobile Equipment (SIM-ME) Interface}
+	\item repeats (and some times amends) large portions of 7816-1/2/3/4
+	\begin{itemize}
+		\item Section 4: physical characteristics
+		\item Section 5: electronic signals, transmission protocol
+	\end{itemize}
+	\item but also specifies what makes the SIM a SIM: Information model, file system, commands
+	\item lats, but not least how to execute authentication: RUN GSM ALGORITHM
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Physical Smart Card Interface}
+\begin{itemize}
+	\item Relevant pins:
+	\begin{itemize}
+		\item VCC: Provides supply voltage (5V, 3V or 1.8V)
+		\item CLK: Provides a clock signal ()
+		\item RST: To reset the card
+		\item IO: bidirectional serial communications
+	\end{itemize}
+	\item Activation sequence triggers card to send ATR (Answer To Reset)
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Bit transmission level}
+\begin{itemize}
+	\item despite the clock, communication is asynchronous!
+	\item baud rate derived from divided clock
+	\item no defined phase relationship between clock and data
+	\item serial data is just like UART/RS232, ... but:
+	\begin{itemize}
+		\item one line for both Rx and Tx
+		\item direction changes once after every byte (ACK in T=0)
+		\item direction changes every few bytes (TPDU state machine)
+		\item timings are actually not very well specified
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Smart Card Communication}
+\begin{itemize}
+	\item based on APDU (Application Protocol Data Unit) as per ISO 7816-4
+	\begin{itemize}
+		\item CLA (class byte)
+		\item INS (instruction byte)
+		\item P1, P2 (parameter bytes)
+		\item Lc (command length)
+		\item Command data
+		\item Le (expected response length)
+		\item Response data
+		\item SW (status word)
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Smart Card Transmission Protocol}
+\begin{itemize}
+	\item different protocols transceive APDUs from/to cards
+	\item T=0 most commonly used with SIM cards
+	\item T=1 also possible but rarely used in SIM
+	\begin{itemize}
+		\item specs require phones to implement both T=0 and T=1
+		\item SIM card can be either T=0 or T=1
+		\item T=1 more used in banking / crypto smart card world
+	\end{itemize}
+	\item APDU gets mapped to protocol-specific TPDU (Transmission Protocol Data Unit)
+	\begin{itemize}
+		\item: Example Command TPDU: A0 A4 00 00 02 3F 00
+		\item: Example Response TPDU: 90 00 (just status word)
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Card Filesystem}
+\begin{itemize}
+	\item most smart cards contain file system abstraction
+	\item cannot be mounted (not exposed like a block device / USB drive!)
+	\item access based on file-level commands (analogy: more like MTP/PTP)
+	\item some similarities to general-purpose (computer) OS file systems:
+	\begin{itemize}
+		\item MF: Master File (root directory)
+		\item DF: Dedicated File (subdirectory)
+		\item EF: Elementary File (data file)
+	\end{itemize}
+	\item However, much more comprehensive than computer OS file systems, e.g.
+	\begin{itemize}
+		\item {\em transparent EF}: opaque stream of data, like PC
+		\item {\em linear fixed EF}: fixed-size records, seekable
+		\item {\em cyclic fixed EF}: ring buffer of records, seekable
+		\item {\em incrementable}: for monotonically incrementing counters
+	\end{itemize}
+	\item Each file has Access Control Conditions (ACC)
+	\begin{itemize}
+		\item read/write/update only after PIN1/PIN2/ADM-PIN
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Key SIM Card Commands}
+\begin{itemize}
+	\item SELECT (file)
+	\item READ RECORD / UPDATE RECORD
+	\begin{itemize}
+		\item for record-oriented EF
+	\end{itemize}
+	\item READ BINARY / UPDATE BINARY
+	\begin{itemize}
+		\item for transparent EF
+	\end{itemize}
+	\item CHANGE CHV / DISABLE CHV / ENABLE CHV
+	\begin{itemize}
+		\item CHV: Card Holder Verification (PIN)
+	\end{itemize}
+	\item RUN GSM ALGORITHM
+	\begin{itemize}
+		\item ask SIM to execute authentication algorithm in card
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{SIM card filesystem hierarchy}
+\begin{itemize}
+	\item MF (3F00)
+	\begin{itemize}
+		\item DF\_TELECOM (7F10)
+		\begin{itemize}
+			\item EF\_SMS
+			\item EF\_MSISDN
+			\item ...
+		\end{itemize}
+		\item DF\_GSM (7F20)
+		\begin{itemize}
+			\item EF\_IMSI
+			\item EF\_Kc
+			\item ...
+		\end{itemize}
+		\item EF\_ICCID
+		\item ...
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+
+
+\begin{frame}{3G: ETSI UICC and the 3GPP USIM}
+\begin{itemize}
+	\item The GSM SIM was fully specified by ETSI in TS 11.11
+	\item As GSM specs moved from ETSI to 3GPP, card specs were split:
+	\begin{itemize}
+		\item ETSI UICC (Universal Intergrated Circuit Card)
+		\begin{itemize}
+			\item like a {\em base class} abstacting out those parts that are not cellular
+				related, or at very least not 3GPP network related
+		\end{itemize}
+		\item 3GPP USIM Applicaiton on top of UICC
+		\begin{itemize}
+			\item specifies those parts specifically relevant to 3GPP networks
+			\item implemented in ADF\_USIM (Application Dedicated File)
+			\item ADF can be entered via SELECT, similar to classic DF
+		\end{itemize}
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{4G: The ISIM}
+\begin{itemize}
+	\item 3G/LTE reuses the existing 3G Authentication (UMTS AKA)
+	\item 4G/LTE simply resuses existing USIM
+	\item some new optional files were introduced in ADF\_USIM
+	\item IMS (IP Multimedia System used for not only VoLTE) specifies ISIM application
+	\begin{itemize}
+		\item stores additional IMS related parameters like SIP server / user identity
+		\item presence of ISIM not required for IMS to work
+		\item if present, ISIM application present next to USIM (and possibly SIM)
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{SIM cards in 5G}
+\begin{itemize}
+	\item 5G reuses existing 3G/4G USIM
+	\item some new optional files were introduced in ADF\_USIM
+	\item SUCI (Subscriber Concealed Identifier) can optionally be computed by SIM
+	\begin{itemize}
+		\item this is the only feature requiring different card / apps on card
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{SIM card hardware}
+\begin{itemize}
+	\item processor core
+	\begin{itemize}
+		\item many different vendors and architectures, from 8-bit 8051 to 32bit ARM
+		\item today quite often ARM SCxxx "Secure Core" family
+		\item documentation on hardware, often even simple one-page data sheets not public
+	\end{itemize}
+	\item built-in RAM
+	\item built-in ROM (at leat boot loader, possibly also OS)
+	\item built-in flash (file system storage, possibly also OS, applications)
+	\item contrary to expensive crypto smart cards, SIM card chip mostly selected purely by low cost
+	\begin{itemize}
+		\item blame pre-paid cards for that
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{SIM card software}
+\begin{itemize}
+	\item Every Smart Card has a Card Operating System (COS)
+	\item Cards without COS are simple memory cards (like I2C eeprom), insufficinet for SIM
+	\item Card OS for Crypto Smart Cards (banking, access control) often publicly known
+	\item SIM Card OS are rarely known / publicly documented or even named
+	\item Example: ARM not only offers SIM card CPU core designs, but also OS (Kigen OS)
+	\item SIM Card OS is {\em implementtaion detail}, almost everything relevant is standardized
+		across OS vendors
+\end{itemize}
+\end{frame}
+
+\begin{frame}{SIM card software modularity}
+\begin{itemize}
+	\item Early SIM cards were (likely) monolithic,
+	\begin{itemize}
+		\item no separation between OS and SIM application
+	\end{itemize}
+	\item Today, SIM cards software is modular
+	\begin{itemize}
+		\item Core OS
+		\item Applications (SIM, USIM, ISIM, ...)
+	\end{itemize}
+	\item traditionally, OS very chip/hardware dependent, non-portable
+	\item traditionally, applications very OS dependent, non-portable
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{Java Cards}
+\begin{itemize}
+	\item independent of SIM cards, Java Smart Cards have been developed
+	\item based on Java Card Platform specifications by Sun (now Oracle)
+	\item first cards in 1996 by Schlumberger (now Gemalto)
+	\item independent of SIM cards, Java Smart Cards have been developed in 1996 by Schlumberger
+	\item most cards implement GlobalPlatform specifications for vendor-independent management
+	\begin{itemize}
+		\item super constrained, weird subset of Java
+		\item special on-card VM (not normal JVM)
+		\item special CAP format (not normal JAR)
+		\item Idea: Portability of Cardlets (card applications)
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Java SIM Cards}
+\begin{itemize}
+	\item There is no functional requirement for a SIM/USIM/ISIM to be a java card
+	\item In reality, most SIM cards probably are Java Cards these days
+	\item Portability is the main driver here
+	\item Operators want to share same applications over multiple vendors/generations of cards
+	\item 3GPP and ETSI specify Java APIs / packages available specifically on Java SIM cards
+\end{itemize}
+\end{frame}
+
+\begin{frame}{SIM Toolkit (STK) / Card Application Toolkit (CAT)}
+\begin{itemize}
+	\item Ability by card to offer applications with UI/menu on the phone
+	\item New APDUs/Instructions
+	\begin{itemize}
+		\item TERMINAL PROFILE
+		\item ENVELOPE
+		\item FETCH
+		\item TERMINAL RESPONSE
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Proactive SIM}
+\begin{itemize}
+	\item SIM cards are "slave" in the 7816 interface
+	\item All actions are triggered by the phone, card can only respond
+	\item Proactive SIM works around this restriction
+	\item Piggy-backs proactive commands to card responses
+	\item Phone can be requested to poll the SIM if it has some proactive commands pending
+	\item Phone can be requested to provide event notifications
+\end{itemize}
+\end{frame}
+
+\begin{frame}{OTA (Over-The-Air)}
+\begin{itemize}
+	\item Ability for operator to transparently communicate with SIM card in the field
+	\item Based on Proactive SIM
+	\item Can use different transport channels, such as
+	\begin{itemize}
+		\item SMS-PP (normal SMS as you know it)
+		\item SMS-CB (bulk update of cards via cell broadcast)
+		\item USSD
+		\item BIP (via CSD, GPRS)
+		\item now also HTTPS
+	\end{itemize}
+	\item Cryptographic security mechanisms specified, but detailed use up to operator
+	\begin{itemize}
+		\item Message Authentication (optional)
+		\item Message Encryption (optional)
+		\item Replay Protection (optional)
+	\end{itemize}
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Remote File Management (RFM)}
+\begin{itemize}
+	\item Common use case of OTA
+	\item Allows remote read / update of files in file system
+	\item Example: Change of preferred/forbidden roaming operator list
+	\item Example (ancient): Backup of phonebook at operator
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Remote Application Management (RAM)}
+\begin{itemize}
+	\item Common use case of OTA
+	\item Allows remote installation / removal of applications on card
+	\item Example: New multi-IMSI application (MVNOs)
+	\item Example: New STK applications
+\end{itemize}
+\end{frame}
+
+\begin{frame}{S@T}
+\begin{itemize}
+	\item a strange beast specified outside of ETSI/3GPP
+	\item allows SIM toolkit applications without writing Java or native applications
+	\item special byte code format interpreted by S@T browser
+	\item to me, one of those WTF? techologies
+\end{itemize}
+\end{frame}
+
+
+\begin{frame}{The CCC event SIM cards}
+\begin{itemize}
+	\item are Java SIM + USIM cards
+	\item support OTA, RAM, RFM
+	\item you can get the ADM PIN and OTA keys from the event GSM team
+	\item a "hello world" Java applet and tools for installation are provided (thanks to shadytel + Dieter Spaar)
+	\item identities and key data can be modified using Osmocom pySim software
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Further Reading}
+\begin{itemize}
+	\item FIXME
+\end{itemize}
+\end{frame}
+
+\begin{frame}{Thanks}
+Thanks for your attention.
+
+	You have a General Public License to ask questions now :)
+\end{frame}
+
+\end{document}
diff --git a/2019/ccc2019-sim_technology_a_z/sim_card_specs.png b/2019/ccc2019-sim_technology_a_z/sim_card_specs.png
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