Transcript Project :: Presentation

TPR 3211 Project 1
Project Title: AES in Javacard
Project ID: 221
Supervisor: Mr. Safi Uddin
Moderator: Mr. Murugadoss
Introduction
Introduction
Introduction
Introduction
One word:
CHANGE
Introduction
Moore’s Law:
“The number of transistors that can fit
in a specific area doubles every 18
months.”
Introduction
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DES (Data Encryption Standard)
First cracked in 1997
Record held at present is 22 hours
Replaced by AES (Advanced Encryption
Standard) in 2001
AES
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Advanced Encryption Standard
Originally called Rijndael
Symmetric block cipher that encrypts and
decrypts data in blocks of 128 bits
Specifies 3 key sizes: 128, 196 and 256 bits
AES

In decimal terms, this means that there are
approximately:
3.4 x 1038 possible 128-bit keys;
6.2 x 1057 possible 192-bit keys; and
1.1 x 1077 possible 256-bit keys.
AES
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DES key are 56 bits long
There are approximately
7.2 x 1016 possible DES keys
There are on the order of 1021 times more
AES 128-bit keys than DES 56-bit keys
AES - Cipher

Pseudocode for cipher:
Cipher(byte in[4 * Nb], byte out[4 * Nb], word w[Nb * (Nr + 1)])
begin
byte
state[4,Nb]
state =
in
AddRoundKey(state, w)
for round = 1 step 1 to Nr – 1
SubBytes(state)
ShiftRows(state)
MixColumns(state)
AddRoundKey(state, w + round * Nb)
end for
SubBytes(state)
ShiftRows(state)
AddRoundKey(state, w + Nr * Nb)
out = state
end
AES – SubBytes(state)

Non linear byte substitution
s0 , 0
s0 ,1
s0 , 2
s0 , 3
s0' ,0
s0' ,1
s0' , 2
s0' ,3
s1' , 0
s1' ,1
s1' , 2
s1' ,3
S-Box
s1, 0
s1,1
s1, 2
s1, 3
s r ,c
s2 , 0
s3, 0
sr' ,c
s2 ,1
s2 , 2
s2 , 3
s2' ,0
s2' ,1
s2' , 2
s2' ,3
s3,1
s3, 2
s3,3
s3' ,0
s3' ,1
s3' , 2
s3' ,3
AES – SubBytes(state)
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For example, if s1,1 = {53}, s’1,1= {ed}
AES – ShiftRows(state)
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Cyclic shift of bytes in rows
s0 , 0
s0 ,1
s0 , 2
s0 , 3
s1, 0
s1,1
s1, 2
s1, 3
s2 , 0
s2 ,1
s2 , 2
s2 , 3
s3, 0
s3,1
s3, 2
s3,3
s0 ,1
s0 , 2
s1, 2
s1, 3
s2 , 2
s2 , 3
s2 , 0
s3,3
s3, 0
s0 , 0
s1,1
s3,1
s0 , 3
s1, 0
s2 ,1
s3, 2
AES – MixColumns(state)
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Columns are treated as 4 term polynomial
Matrix multiplication with a fixed polynomial
 s0' , c  02
 '  
 s1, c    01
 s2' , c   01
 '  
 s3, c  03
03 01 01  s0, c 
s 

02 03 01  1, c 
01 02 03  s2, c 
 
01 01 02  s3, c 
AES – Inverse Cipher

Pseudocode for inverse cipher:
InvCipher(byte in[4 * Nb], byte out[4 * Nb], word w[Nb * (Nr + 1)])
begin
byte
state[4,Nb]
state = in
AddRoundKey(state, w + Nr * Nb)
// See Sec. 5.1.4
for round = Nr - 1 step -1 to 1
InvShiftRows(state)
// See Sec. 5.3.1
InvSubBytes(state)
// See Sec. 5.3.2
AddRoundKey(state, w + round * Nb)
InvMixColumns(state)
// See Sec. 5.3.3
end for
InvShiftRows(state)
InvSubBytes(state)
AddRoundKey(state, w)
out = state
end
AES – InvShiftRows(state)

Cyclic shift of bytes in rows
s0 , 0
s0 ,1
s0 , 2
s0 , 3
s1, 0
s1,1
s1, 2
s1, 3
s2 , 0
s2 ,1
s2 , 2
s2 , 3
s3, 0
s3,1
s3, 2
s3,3
s0 ,1
s0 , 2
s1, 3
s1, 0
s1,1
s2 , 2
s2 , 3
s2 , 0
s3,1
s3, 2
s3,3
s0 , 0
s0 , 3
s1, 2
s2 ,1
s3, 0
AES – InvSubBytes(state)

Non linear byte substitution
s0 , 0
s0 ,1
s0 , 2
s0 , 3
s0' ,0
s0' ,1
s0' , 2
s0' ,3
s1' , 0
s1' ,1
s1' , 2
s1' ,3
S-Box
s1, 0
s1,1
s1, 2
s1, 3
s r ,c
s2 , 0
s3, 0
sr' ,c
s2 ,1
s2 , 2
s2 , 3
s2' ,0
s2' ,1
s2' , 2
s2' ,3
s3,1
s3, 2
s3,3
s3' ,0
s3' ,1
s3' , 2
s3' ,3
AES – InvMixColumns(state)
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Columns are treated as 4 term polynomial
Matrix multiplication with a fixed polynomial
 s0' , c   0e 0b 0d 09   s0, c 
 '  
 s 
09
0
e
0
b
0
d
s
 1, c   
  1, c 
 s2' , c  0d 09 0e 0b   s2, c 
 '  
 
 s3, c   0b 0d 09 0e   s3, c 
Smartcard vs Javacard
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A smartcard is a “credit
card” with a “brain” in it
Must communicate with a device to gain access
to a display device or network
Can be plugged into a reader (card terminal) or
operate using radio frequencies
Smartcard vs Javacard
A Javacard is a smartcard,
a smartcard is not a Javacard
Javacard
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There is an estimated 3 billion smartcards in the
world at the present moment, and all the major
smartcard players have licensed Javacard
Javacard is a smart card that is capable of running
programs written in Java
It is designed to run on 8-bit microprocessors with
as little as 256 bytes of RAM (no, I didn’t leave out
the K!) and 14 kilobytes of ROM
It enables the first true multi-application cards, it
speeds and simplifies application development in
very small memory environments
Javacard
Javacard
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Javacard Virtual Machine
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Due to limited memory resources, it is not
possible to fit the JVM into Javacard
3 strategies:
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Small JVM is introduced
Javacard API is deprecated from Java API
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No threads, security manager, synchronization, multidimensional arrays, large primitive data types
Split architecture

Bytecode at both ends – card terminal end and Javacard
end
Javacard
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Communication with the outside world:
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Application Protocol Data Unit
Data package (maximum size is 255 bytes)
A Javacard always waits for “Command APDU”
from the reader (card terminal software)
Responds with “Response APDU”
Javacard
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Javacard Runtime Environment
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Contains API classes and the JVM
Responsible for:
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applet installation and initialisation
selection and deselection
APDU dispatching
transaction management
catching unchecked exceptions
assigns AID for each applet
Javacard
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How does it work?
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Java data is compiled into bytecode and sent to
card reader (card terminal driver)
Reader converts bytecode into card bytecode
Wraps card bytecode into data package “Select
APDU” to tell the Javacard to let go of current
active applet and select the new current applet
JCRE in Javacard will assign new applet AID
Communication by “Command APDU” and
“Response APDU”
AES in Javacard
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Why Javacard?
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Smart cards provide a secure, portable platform for "any
time, anywhere" computing that can carry and manipulate
substantial amounts of data, especially an individual's
personal digital identity
The Java Card API allows applications written for one card
to be downloaded "in place" into any other card
The Java Card thus allows smart cards to become a
general-purpose computing platform and creates a
potentially huge market for application software and
development -- especially for financial, telecommunications,
television, and security applications
AES in Javacard
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Why AES in Javacard?
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Increasingly, physical keys are being replaced by
cryptographic keys, which are typically a thousand bits in
size
Modern smart cards are the ideal carriers for such keys,
because they have enough computing power to do the
necessary encryption or decryption on-card, so that the
secret key never has to leave the card
One of the reasons Rijndael was chosen as AES was
because of its efficiency in low memory environments
AES in Javacard
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Hardware Specifications:
AES in Javacard
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Hardware Specifications:
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GemPC-410 card reader
GemXpresso RAD III PK IS Javacard
USB to Serial converter
AES in Javacard
GUI Card Terminal
Application
Ocean SDK
(optional)
Gemplus GemPC-410
Card Terminal Driver
Windows 98
JDK 1.2.2
Inprise JBuilder 3.5
Card Terminal Application
Gemplus GemXpresso
RAD III PK IS Kernel
AES Javacard
applet
AES in Javacard
Software Specifications:
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Windows 98
JDK1.2.2
Inprise JBuilder 3.5
Gemplus GemXpresso RAD III PK IS Kernel
Gemplus GemPC-410 Card terminal driver (OCF
with PC/SC bridge)
AES in Javacard
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Solution methods:
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Research into the protocols, standards involved in project
Implementation of an AES applet model on a Java platform
Design and coding of a Javacard applet, test run on a
simulation environment (Gemplus Simulation Environment)
Design and coding of card terminal application
Test run both Javacard applet and card terminal application
AES in Javacard
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Prototype development phase 1:
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Tested applet security sandbox with an applet to read
c:\autoexec.bat
AES in Javacard
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After creating keystore, signing applet and
specifying permission in policy file, applet can be run
AES in Javacard
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Prototype development phase II:
Figure: splash screen of prototype
AES in Javacard
Figure: encryption screen 1 of prototype
AES in Javacard
Figure: encryption screen 2 of prototype
AES in Javacard
Figure: decryption screen 1 of prototype
AES in Javacard
Figure: decryption screen 2 of prototype
AES in Javacard
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Prototype behaviour:
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Encryption longer than decryption
AES in Javacard
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Implementation plan for coming trimester:
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Choose between OCF and PC/SC
Develop Javacard applet
Run Javacard applet using GSE (Gemplus
Simulation Environment) simulator to determine
memory requirement, implementation errors, flow
of communication, etc.
Develop Card Terminal Application using OCF or
PC/SC platform.
AES in Javacard
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Conclusion:
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AES in Javacard is a new platform, a new
method, a new thinking.
AES in Javacard
THE END
Thank you for your attention