com.fasteasytrade.JRandTest.Algo
Class Skipjack

java.lang.Object
  com.fasteasytrade.JRandTest.Algo.Cipher
      com.fasteasytrade.JRandTest.Algo.Skipjack

public class Skipjack

extends Cipher

Skipjack algorithm copyright (c) 2005 Zur Aougav.

Hand translation to java from C implementation.

Originally written by Panu Rissanen 1998.06.24
optimized by Mark Tillotson 1998.06.25
optimized by Paulo Barreto 1998.06.30
gnupg support by Werner Koch 1998.07.02

Author:

Zur Aougav

Field Summary

(package private) static byte[]	fTable The F-table byte permutation (see description of the G-box permutation)
(package private) boolean	initialized
(package private) byte[][]	tab

Constructor Summary

Skipjack()

Method Summary

static String	byte2hex(byte b)
boolean	decrypt_block(byte[] in, byte[] out) Decrypt a single block of data.
boolean	encrypt_block(byte[] in, byte[] out) Encrypt a single block of data.
(package private) int	g(int w, int i, int j, int k, int l) The key-dependent permutation G on V^16 is a four-round Feistel network.
(package private) int	g0(int w)
(package private) int	g1(int w)
(package private) int	g2(int w)
(package private) int	g3(int w)
(package private) int	g4(int w)
(package private) int	h(int w, int i, int j, int k, int l) The inverse of the G permutation.
(package private) int	h0(int w)
(package private) int	h1(int w)
(package private) int	h2(int w)
(package private) int	h3(int w)
(package private) int	h4(int w)
static void	main(String[] args)
(package private) boolean	setupKey(byte[] key) Preprocess a user key into a table to save and XOR at each F-table access.
void	Test()

Methods inherited from class com.fasteasytrade.JRandTest.Algo.Cipher

compareBytes

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

initialized

boolean initialized

tab

byte[][] tab

fTable

static final byte[] fTable

The F-table byte permutation (see description of the G-box permutation)

Constructor Detail

Skipjack

public Skipjack()

Method Detail

setupKey

boolean setupKey(byte[] key)

Preprocess a user key into a table to save and XOR at each F-table access.

Parameters:

key - key length must be >= 10 bytes. Process the first 10 bytes.

encrypt_block

public boolean encrypt_block(byte[] in,
                             byte[] out)

Encrypt a single block of data.

In and out blocks' length must be 8 bytes.

Returns:

false if input and output blocks are null, or length is not = 8. Else, true.

decrypt_block

public boolean decrypt_block(byte[] in,
                             byte[] out)

Decrypt a single block of data.

In and out blocks' length must be 8 bytes.

Returns:

false if input and output blocks are null, or length is not = 8. Else, true.

g

int g(int w,
      int i,
      int j,
      int k,
      int l)

The key-dependent permutation G on V^16 is a four-round Feistel network. The round function is a fixed byte-substitution table (permutation on V^8), the F-table. Each round of G incorporates a single byte from the key.

g0

int g0(int w)

g1

int g1(int w)

g2

int g2(int w)

g3

int g3(int w)

g4

int g4(int w)

h

int h(int w,
      int i,
      int j,
      int k,
      int l)

The inverse of the G permutation.

h0

int h0(int w)

h1

int h1(int w)

h2

int h2(int w)

h3

int h3(int w)

h4

int h4(int w)

byte2hex

public static String byte2hex(byte b)

Test

public void Test()

main

public static void main(String[] args)