SMART CARDS •

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SMART CARDS
Contents of today’s lecture:
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1. Introduction
What is a smart card?
Use of SM’s
Objectives
Future views
HST-project
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2. Technology
Physical structure
Different types of SM’s
Chip
Standards
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3. Security issues
• Features
• Authentication
• Signatures
• SET
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4. Applications
• Multiple Application Smart Card
Systems
• Electronic Smart Passport/Visa
• Different applications of the future
Introduction to smart cards
- What is a smart card?
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A credit card-sized plastic token with an embedded microchip
(integrated circuit chip)
Provides
• Persistent, protected storage
• Memory capacity (4K - 32K is typical)
• Computational capability and Processing power (a small CPU)
Self-contained
 Doesn’t need to depend on potentially vulnerable external
resources
Today, smart cards are used by millions of cardholders worldwide and
are at work in more than 90 countries, primarily in Europe and the Far
East, processing point-of-sale transactions, managing records, and
protecting computers and secure facilities.
SMART…? Usage of smart cards
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In different applications which require strong security protection and
authentication
• Identification card
• Medical card
• Credit/debit bank card (as an electric wallet)
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All require sensitive data to be stored on the card, such as:
• biometrics information
• personal medical history
• cryptographic keys for authentication
• Logging on to networks
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Wirelessly:
• Public transport payments (tickets) etc.
Objectives
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Accelerate and harmonize the development and the use of sm’s
Interoperability:
- Build a consensus for system interoperability
- Harmonize smart cards based infrastructures across sectors
Multi-application cards:
- Advance smart card technology for seamless use of multi-application
cards.
- Contribute to the development of innovative applications and
services.
Security of transactions:
- Agree on common protection profiles and specifications.
- Develop certification services and cryptography support.
User Acceptance of Smart cards
Accessibility
Interoperability
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different cards are usually not interchangeable
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Memory cards usually have different interface characteristics from
microprocessor cards:
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different data formats and/or electrical signals across the interface between card
and terminal
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provide the different mixes of applications that various types of cardholder will
want (BUT: rarely accepted at the moment)
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A rare example of an attempt at interoperability:
The UK EMV bank debit/credit card scheme demands interchangeability from
its various suppliers - and gets it at the level at which the cards are used by the
cardholder.
Future views
“Smart cards are the keys to the media and information revolution no
matter whether it is wired or wireless”
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magnetic strip card will be replaced and integrated together into a
multi-application card
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Use becomes daily
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Will be used to carry a lot of sensitive and critical data
• issues about whether or not the smart card is secure and safe
enough to store that information
HST-project (Finnish research in 1999)
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A Governmental project in Finland to build national Public Key Infrastructure
(PKI).
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Key concept in HST is Electronic ID-card, smart card which contains users
cryptographic keys and certificates.
• With this card and other PKI components person can be digitally identified
in Internet where he or she can use it for example to sign documents.
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Card contains its own operating system, special RSA-processor, specific
software and certificates. In the card there are two certificates and private keys:
one for authentication and encryption, other one for digital signature.
Certificates are protected with PIN-codes which are only known to the card
owner.
More of this can be read at:
http://www.tcm.hut.fi/Opinnot/Tik-110.401/1999/Tutkielmat/kolsi/HST.pdf
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Technology
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Physical structure
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Different types of SM’s
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Chip / Standards
Physical Structure
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Made up of three elements
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A physical card (plastic)
A printed circuit chip
An integrated circuit chip (microcontroller)
(Chips are embedded on the card)
Printed circuit conforms to ISO standard 7816/3 which provides five connection
points for power and data
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The printed circuit protects the circuit chip from mechanical stress and static electricity
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The capability of a smart card is defined by its integrated circuit chip.
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Chip made from silicon which is not flexible and particularly easy to break
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In general, the size, the thickness and bend requirements for the smart card are
designed to protect the card from being spoiled physically
Different types of SM’s
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Java cards
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SIM cards
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eCash cards
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Contact / Contactless Smart
Cards
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Proximity cards
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Hybrid/twin cards
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Combi cards
Contact / Contactless Smart Cards
CONTACT:
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Cards the size of a conventional
credit or debit card with a single
embedded integrated circuit chip
that contains just memory or
memory plus a microprocessor.
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Popular Uses:
Network security, vending, meal
plans, loyalty, electronic cash,
government IDs, campus IDs, ecommerce, health cards
CONTACTLESS:
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Cards containing an embedded
antenna instead of contact pads
attached to the chip for reading and
writing information contained in the
chip's memory.
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Popular Uses:
Student identification, electronic
passport, vending, parking, tolls,
IDs
Proximity cards
Hybrid/twin cards
Combi cards
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"Prox cards" communicate through an antenna similar to contactless smart cards
except that they are read-only.
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Cards containing two or more embedded chip technologies such as a prox chip
with its antenna and a contact smart chip with its contact pads are Hybrid/twin
cards.
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Uses: Security, identification and access control
Uses: Accommodates legacy system infrastructure while adding applications that
require different e-card technologies
The combi card has one smart chip embedded in the card that can be accessed.
This form of smart card is growing in popularity because it provides ease-of-use
and high security in a single card product.
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Uses: Mass transit and access control combined with other applications such as
network security, vending, meal plans, loyalty, etc.
Java card
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The Java Card specifications enable Java technology to run on smart cards
and other devices with limited memory
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Multi-Application Capable
- Java Card technology enables multiple applications to co-exist securely on a
single smart card
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Dynamic:
- New applications can be installed securely
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Secure:
- relies on the inherent security of the Java programming language to provide a
secure execution environment.
- platform's proven industry deployments and security evaluations ensure that
card issuers benefit from the most capable and secure technology available
today.
CHIP - What does the chip contain
and what is it made for?
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Made for the portable storage and retrieval of data
Used memory types:
ROM Read only memory (mask ROM)
PROM Programmable read only memory
EPROM Erasable programmable ROM
EEPROM Electrically erasable PROM
RAM Random access memory
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Memory-only chips are functionally similar to a small floppy disk.
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Chips that contain both memory and a microprocessor are also
similar to a small floppy disk, except they contain an "intelligent"
controller used to securely add, delete, change, and update
information contained in memory.
Standards
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The standardization of smart card systems is an ongoing process. One
of the standards most referred to is the ISO-7816 standard. It is
divided as follows:
Part 1: Physical characteristics
Part 2: Dimensions and location of the contacts
Part 3: Electronic signals and transmission protocols
Part 4: Industry commands for interchange
Part 5: Number system and registration procedure for application identifiers
Part 6: Interindustry data elements
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Present projects:
• Smart MEIJI is a joint project designed to reinforce co-operation
between Europe and Japan in the field of smart cards
SECURITY ISSUES
- Features
- Authentication
- Signatures
- SET
Security features
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An important aspect to smart cards to prevent unauthorized users from gaining access to
information contained on the card.
The advantage smart cards have over magnetic stripe cards is that the smart card contains
the computer chip which stores the password or PIN.
the password is not sent over a communication line to a computer system for
verification, which can easily be tapped.
most important part of a smart card is the software that provide the applications
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It has been established that any secure transaction involves 6 generic functions:
• Data Protection
• Identification of the cardholder
• Mutual authentication
• Secure writing
• Certification or signature
• Encryption
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The security imposed to protect the transmission between the card and the outside world
by the mean of cryptographic technique in order to control the:
• writing operation
• authentication the card or the terminal
• origin of the message
• transmission of cryptographic keys
Authentication
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The most common method used for cardholder verification at present
is to give the cardholder a PIN (Personal Identification Number)
which he or she has to remember.
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PINs can be stolen or abused.
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The only truly effective method of Cardholder Verification is the
measurement of a physiological characteristic unique to an individual
and incapable of fraudulent replication or abuse.
Biometrics:
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Iris and Retinal scans,
Face or Hand geometry,
DNA,
most acceptable attribute is the fingerprint.
Signatures
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Electronic signatures in combination with a PKI.
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Loaded with private key(s), public key certificates and some ways to
point securely to non-repudiation policies
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The loading procedure and the data formats need to be specified.
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The use of standardized APIs to allow electronic signature enabled
applications to interface with any kind of smart card is to be considered
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Blind signatures allow privacy features to be built into applications.
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Ecash, for instance, uses blind signatures to offer payer anonymity.
Privacy issues are certain to play an increasingly important role in the
continuing development of digital signature applications.
SET (Secure Electronic Transaction)
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When a purchase is made:
- the user's credit card account information is verified as authentic to
the vendor and then debited at the user's financial institution.
- All transmissions of information are secure through the use of the
SET (Secure Electronic Transaction) Protocol 1.0, developed by Visa
and MasterCard, which encrypts all data during transmission.
APPLICATIONS
• Application areas
• Multiple Application Smart Card Systems
• Different applications of today and the future
Applications
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With advanced technologies special solutions for various applications
have been created with smart cards, for example in the fields of:
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Mobile telephony
Gaming and Wagering
Healthcare systems
Network security
Personnel access
Logistics management
Multiple basic application areas and industries in our daily lives
Multi-application sm’s
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Most of the smart card systems in use today serve one purpose and
are related to just one process:
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smart telephone card
electronic money
medical card
electronic identification card
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All of these applications are stored in different smart card systems
separately  require users to carry multiple cards for multiple
applications
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The smart card has the capability to integrate those applications
together to form a multiple application card by utilizing its embedded
microprocessor and memory storage spaces.
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3 different infrastructures of multiple application smart card systems
LAST SLIDE…
Any questions ?
Thank you for your time!
2. Security
2.1 Introduction
2.2 Life cycle of smart card
2.3 Logical Structure
2.4 Access Control
2.1 Introduction
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What makes the smart card better than normal magnetic stripe card?
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The advantage smart cards have over magnetic stripe cards is that the
smart card contains the computer chip which stores the password or PIN
Therefore, the password is not sent over a communication line to a
computer system for verification, which can easily be tapped.
2.2 Life cycle of smart card
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Divided into five phases (on most smart cards)
These phases justified by
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Limitation of transfer and access of data is incremental throughout different
phases
Different areas of smart card protected throughout the life cycle
2.2.1 Fabrication phase
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Carried out by the chip manufacturers
A Fabrication Key (KF) is added to protect the chip
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unique and is derived from a master manufacturer key
Fabrication data will be written to the circuit chip
2.2.2 Pre-personalisation phase
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Done by Card manufacturers
Chip will be mounted on the plastic card
The connection between the chip and the printed circuit will be made
Fabrication key (KF) changed to Personalisation key (KP)
Personalisation lock Vper
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No further modification of the KF
Physical memory access instructions will be disabled
Access of the card can be done only by using logical memory addressing
2.2.3 Personalisation phase
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Conducted by the card issuers
Data files contents and application data are written to the card
Information of card holder stored to the chip (PIN, Unlocking PIN)
Utilisation lock Vutil
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No further modification of the KP
2.2.4 Utilisation phase
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Phase for the card owners use of the card
Access of information on the card will be limited by the security
policies set by the application
2.2.5 End-of-Life phase
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Two ways:
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1. invalidation lock
• All operations will be disabled (except read)
2. Control system irreversibly blocks access
• All operations will be disabled
2.2.6 Summary of life-cycle
Areas/Phases
Fabrication
Pre-personalisation
Access mode
Personalisation
Physical addressing
Utilisation
Logical addressing
System
Not accessible
Fabrication (keys)
Write KF
Write KP
Not accessible
Fabrication (data)
Read, write, erase
Read
Read
Directory
Read, write, erase
According to logical file access conditions
Data
Read, write, erase
According to logical file access conditions
Optional code
Read, write, erase
Not accessible
Table 1: Phases and access rights of smart card's life cycle
(Source: Philips DX smart card reference manual, 1995)
End-of-Life
2.3 Logical Structure
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After a smart card is issued to the consumer, protection of the card will
be controlled by the application operating system mainly
Access of data has to be done through the logical file structure on the
card
2.3 Logical Structure (2)
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A smart card can be viewed as a disk drive, including
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master file (MF) (similar to root in e.g. MS-DOS)
• dedicated files (DFs) (similar to normal folder)
• elementary files (EFs) (similar to normal files)
2.3 Logical Structure (3)
Figure 2: Logical file structure of smart card
2.3 Logical Structure (4)
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In short,
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the file structure of the smart card OS is similar to other common OS such
as UNIX
However, it provides a greater security control
• accessing conditions and file status field for each file header
• file lock
2.4 Access Control
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Each file attached with a header which indicates the access conditions
The fundamental principle of the access control is based on the correct
presentation of PIN numbers
Primarily, the access conditions can be divided into five following nonhierarchical levels ->
2.4 Access Control (2)
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Always (ALW)
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no restrictions
Card holder verification 1 & 2 (CHV1 & 2)
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Access granted if valid CHV presented
Administrative (ADM)
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Allocation and administrative authority
Never (NEV)
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Access always forbidden
2.4 Access Control (3)
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PIN presentations:
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PIN and unblocking PIN
Stored in separate elementary files (EF)
Access conditions prevent changes
Changes can be made by issuing old and new PIN
If both PINs fail, irreversible blockage will occur
3. Attacks
3.1 Introduction
3.2 Logical attacks
3.3 Physical attacks
3.4 Mathematical attacks
3.5 Conclusions
3.1 Introduction
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Target of attacks:
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The secret of the cryptographic algorithm
The keys stored
The access control
Information strored on card
3.2 Logical attacks
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Starting point:
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EEPROM (electrically erasable programmable read only memory) write
operations can be affected by unusual voltages and temperatures ->
• information can be trapped by raising or dropping the supplied voltage
to the microcontroller
3.2 Logical attacks (2)
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Example 1. Attack of PIC16C84 microcontroller
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Erasing the memory by raising the voltage VCC (Supply voltage) to VPP
(Programming voltage) - 0.5V
3.2 Logical attacks (3)
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Example 2. Attack on DS5000 security processor
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A short voltage drop can release the security lock without erasing the
secret data sometimes
3.2 Logical attacks (4)
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Example 3. Usage of analogue random generator
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Creates cryptographic keys that will produce an output of almost all 1’s
when the supply voltage is lowered slightly.
3.2 Logical attacks (5)
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Prevention of logical attacks
• some security processors implemented sensors which will cause an
alarm when there is any environmental changes
3.3 Physical attacks
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Invasive physical attacks
Reverse engineering of the circuit chips
erasing the security lock bit by focusing UV light on the EPROM
probing the operation of the circuit by using microprobing needles
using laser cutter microscopes to explore the chip
3.3 Physical attacks (2)
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Example 1. Invasive physical attacks
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Circuit chip removed from the plastic card
The resin dissolved
The acid and resin washed away
>>>>> The chip can be examined and attacked directly (only for US $30)
3.3 Physical attacks (3)
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Example 2. Attacking by reverse engineering circuit chips (High quality
laboratory needed)
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etching away a layer of a chip at a time
thin film of a metal attached to chip creating a diode -> filmed with electron beam
PCs image processing system software used to analyze the pictures
The layout and function of the chip can then be identified
3.3 Physical attacks (4)
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also…
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Technique developed by IBM can be used to observe the operation of the
chip. As a result its secret can be fully revealed
3.3 Physical attacks (5)
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Prevention of physical attacks
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Acid added to chip when the chip is tampered, acid destroys all vital
information on the chip
3.4 Mathematical attacks
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Done by mathematical geniuses
Fully theoretical
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Usage of complicated mathematical calculations and formulas
3.5 Conclusions
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Today's, most of the attacks available are classified as attacks where
the cost associated to break the system are far more than the cost of
the system itself, or it has to spend several or hundred years of
computing power to break into a single transaction…
3.5 Conclusions (2)
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..but still questions remain:
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Can the PIN code be downloaded by the card reader and then stored
somewhere?
When signature is used it is still possible that you don’t know what you’re
signing?!
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