463.16 Identification Tokens (IDs and implants)

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463.16 Identification Tokens

(IDs and implants)

Computer Security II

CS463/ECE424

University of Illinois


Identification


“The function of
identification

is to map a
known quantity
to an
unknown entity
so as to
make it known. The known quantity is called
the identifier (or ID) and the unknown entity is
what needs identification...”


Wikipedia


Identification alone may provide no guarantee
of getting the right mapping.


Username:


Password:



Automated Identification (AID)


Identification can be aided by automation to work with fewer
human interventions.


Either replace traditional identification procedure to provide
more seamless workflow, or create new applications:


Commercial: Product identification, Supply chain & Logistics,
E
-
Commerce.


Healthcare: Equipment tracking/ Patient Identification


Transportation: E
-
Tickets


Others: Animal Tracking, Vehicle / People Identification





AID Technologies
-

Barcode


Printing ID in a way which is machine readable.
Information can be expressed via different
symbologies.


History: developed in 1948, commercial use 1966,


not commercially successful until the 1980s.


Recent developments: 2D barcodes and
semacodes.


Characteristics: cheap, short/long operating range,
line of sight, low data rate.


Current uses: Groceries


UPC, Books


ISBN, drugs


Magnetic Stripe Card


Stores data by


modifying the magnetism of iron
-
based particles on a
band of magnetic material, as in video tape.


sticking such magnetic tape to a plastic card base.


Characteristics: cheap, higher data rate,
near operating range, some risk of damage,
easily read and counterfeited, highly
standardized.


Current uses: ID cards (UID), Credit & Debit
Cards, Subway and Bus Card.

Smart Card


A smart card is a pocket
-
sized card with
embedded integrated circuits that can
process information.


Contact or contactless.


Often comes with tamper resistant
feature but this adds to the cost.


Current uses: Mobile phone SIM, ATM
Cards, contactless CC/DC, driver’s
license.



Smart cards are often replaced by magnetic
stripe cards and networked terminals. Why is
this?


Discussion

7

RFID


Using radio frequency to transfer
identifier.


Characteristics: very flexible

(HF/LF/UHF, active/passive,
implantable..), convenient, does not
require line of sight.


Concerns: privacy, cancer (implantable
tags).


Emerging markets: medical, retail, …


http
://www.youtube.com/watch?v=eob532
iEpqk

Biometrics

Biometrics:

Universality

Uniqueness

Face

H

L

Fingerprint

M

H

Hand geometry

M

M

Keystrokes

L

L

Hand veins

M

M

Iris

H

H

Retinal scan

H

H

Signature

L

L

Voice

M

L

Facial
thermograph

H

H

Odor

H

H

DNA

H

H

Gait

M

L

Ear recognition

M

M

Biometrics


Identify humans based upon one or more intrinsic physical or
behavioral traits.


Characteristics: convenient / inconvenient, not very reliable
(collision, effect of aging), usually more expensive.


Current uses: Personal laptops, digital IDs,
ePassport

(US, Brazil,
Germany).


Concerns: once compromised, it is compromised for life, but
may be hard to fake.


Mythbusters

on fingerprint:
http://www.youtube.com/watch?v=LA4Xx5Noxyo


Tradeoffs


Barcode:


Advantage: conforms to common standards and regulations, proven
reliability, cheap


Disadvantage: inconvenient in some respects, limited applications,
low capacity, not re
-
writable, easy to copy.


Magnetic Stripe


Advantage: conform to common standards and regulations,
acceptable reliability, cheap, higher capacity.


Disadvantage: inconvenient in some respects, limited applications,
not easily re
-
writable, easy to copy.


Smart card


Advantage: conforms to common standards and regulations, high
reliability, high capacity, flexible (contact/contactless,
rewritable/not), computation & security features.


Disadvantage: more expensive, limited applications (range).


Tradeoffs


RFID


Advantage: higher capacity, more applications, convenient, flexible
(long/short range, re
-
writable/not, passive/active)


Disadvantage: poor standardization, reliability (viz. around metal &
liquids), privacy concerns, some expensive.


Biometrics


Advantage: sometimes very convenient, may be cheap (need only the reader).


Disadvantage: limited applications, no extra information, may be expensive
(high cost of readers), reliability a concern, sometimes not convenient.


More capable tokens are becoming common


These often have their own power source and
perform secure authentication remotely,
sometimes at a substantial distance

Key Fobs

13

History


1950’s: Garage door
openers used one
common frequency for
all garage doors


1970’s: DIP switches
used to vary transceiver
/ transmitter codes


1993: Lectron’s passive
keyless entry for
Corvette

14

Applications in Automobiles

Three main components:


Remote Keyless Entry System (RKE)


Also includes passive keyless entry


Remote Keyless Ignition System (RKI)


Immobilizer (Im)

15

Basic Structure


Contains 2 parts:


Transmitter (typically key fob)


Receiver (typically automobile)


Current designs use:


Two way communication


Low Frequency (LF) for sleeping mode

17

Communication Protocols

1.
Fixed Code Technique


Transmit constant
code within certain
range, similar to
garage door openers in
the past.


Typically unusued:
moved away from this
because of scan and
replay attacks

18

[AlrabadyM03] [AlrabadyM05]

Communication Protocols

2.
Rolling Code Technique


Initially start with 40
-
bit counter


Each communication first transmits counter, then
increments it in algorithmic fashion


Automobile verifies transmitted code


Resynchronization issues

19

Communication Protocols

3.
Challenge
-
Response Technique


Automobile challenges key fob by sending random
number


Key fob encrypts it and sends it back to automobile


Automobile compares for validity


Used in remote keyless entry

20

Security Issues

Types of attacks:

1.
Scan attack


generic brute force

2.
Playback attack


record old messages

3.
Two
-
thief attack


generic man
-
in
-
the
-
middle
attack

4.
Challenge forward prediction attack


predict
future answer from previous

5.
Dictionary attack


compile valid pairs

Implantable
Medical Devices
(IMDs)

22

[DenningBFGKM10]


Complex therapies


Radio
interfaces


Monitoring
over Internet


Algorithms
for problem
detection


More
storage, better CPU,
...

Trends in Cardiac Devices

23


Steal / Build Device
Programmer


Eavesdrop on info


Drain energy


Turn off therapies


Induce therapies



Attacks on ICD

24


Authenticate device
programmers
?


Key management is hard
.
Revocation
?


Encrypt all
transmissions
?


Under what key
? Must
fail
open! Medical personnel
need emergency access.


Challenge
: design to fail open
.

CIA on IMD: Safety
vs

Security

25


What would be some practical ways to
introducing fail
-
open
in an IMD?

Discussion

26


[AlrabadyM03] Some Attacks Against Vehicles’ Passive Entry Systems
and Their Solutions,
Ansaf

Ibrahem

Alrabady

and Syed
Masud

Mahmud.
IEEE Transactions on Vehicular Technology, vol. 52, no. 2, pp. 431
-
439 ,
March 2003.


[AlrabadyM05] Analysis of Attacks Against the Security of Keyless
-
Entry
Systems for Vehicles and Suggestions for Improved Designs,
Ansaf

Ibrahem

Alrabady

and Syed
Masud

Mahmud. IEEE Transactions on
Vehicular Technology, vol. 54, no. 1, pp. 41
-
50, January 2005.


[DenningBFGKM10] Patients
, Pacemakers, and Implantable
Defibrillators: Human Values and Security for Wireless Implantable
Medical Devices.

T
. Denning, A.
Borning
, B. Friedman, B.T. Gill, T. Kohno,
and W.H.
Maisel
.


28th Conference on Human Factors in Computing Systems (CHI), April
10
-
15, 2010.


Reading

27


Final Exam: Friday 13 May from 1:30 to 4:30 in
this room.


Practice Exam: Thursday May 5.


ICES

Ending Matters

28


Primary purpose of the exam: assess retention of
materials discussed in class.


Secondary purpose: assess ability to produce
new ideas about relationships, applications, and
issues.


Written exam, closed book.


Will include questions from the practice exam
and discussion questions from the slides.

Aim and Nature of Final Exam

29