org.bouncycastle.crypto.engines
Class BlowfishEngine

java.lang.Object
  org.bouncycastle.crypto.engines.BlowfishEngine

All Implemented Interfaces:

BlockCipher

public final class BlowfishEngine
extends java.lang.Object
implements BlockCipher

A class that provides Blowfish key encryption operations, such as encoding data and generating keys. All the algorithms herein are from Applied Cryptography and implement a simplified cryptography interface.

Field Summary

private static int	BLOCK_SIZE
private boolean	encrypting
private static int[]	KP
private static int[]	KS0
private static int[]	KS1
private static int[]	KS2
private static int[]	KS3
private int[]	P
private static int	P_SZ
private static int	ROUNDS
private int[]	S0
private int[]	S1
private int[]	S2
private int[]	S3
private static int	SBOX_SK
private byte[]	workingKey

Constructor Summary

BlowfishEngine()

Method Summary

private void	Bits32ToBytes(int in, byte[] b, int offset)
private int	BytesTo32bits(byte[] b, int i)
private void	decryptBlock(byte[] src, int srcIndex, byte[] dst, int dstIndex) Decrypt the given input starting at the given offset and place the result in the provided buffer starting at the given offset.
private void	encryptBlock(byte[] src, int srcIndex, byte[] dst, int dstIndex) Encrypt the given input starting at the given offset and place the result in the provided buffer starting at the given offset.
private int	F(int x)
java.lang.String	getAlgorithmName() Return the name of the algorithm the cipher implements.
int	getBlockSize() Return the block size for this cipher (in bytes).
void	init(boolean encrypting, CipherParameters params) initialise a Blowfish cipher.
int	processBlock(byte[] in, int inOff, byte[] out, int outOff) Process one block of input from the array in and write it to the out array.
private void	processTable(int xl, int xr, int[] table) apply the encryption cycle to each value pair in the table.
void	reset() Reset the cipher.
private void	setKey(byte[] key)

Methods inherited from class java.lang.Object

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

Field Detail

KP

private static final int[] KP

KS0

private static final int[] KS0

KS1

private static final int[] KS1

KS2

private static final int[] KS2

KS3

private static final int[] KS3

ROUNDS

private static final int ROUNDS

See Also:

Constant Field Values

BLOCK_SIZE

private static final int BLOCK_SIZE

See Also:

Constant Field Values

SBOX_SK

private static final int SBOX_SK

See Also:

Constant Field Values

P_SZ

private static final int P_SZ

See Also:

Constant Field Values

S0

private final int[] S0

S1

private final int[] S1

S2

private final int[] S2

S3

private final int[] S3

P

private final int[] P

encrypting

private boolean encrypting

workingKey

private byte[] workingKey

Constructor Detail

BlowfishEngine

public BlowfishEngine()

Method Detail

init

public void init(boolean encrypting,
                 CipherParameters params)

initialise a Blowfish cipher.

Specified by:

init in interface BlockCipher

Parameters:

encrypting - whether or not we are for encryption.

params - the parameters required to set up the cipher.

Throws:

java.lang.IllegalArgumentException - if the params argument is inappropriate.

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from interface: BlockCipher

Return the name of the algorithm the cipher implements.

Specified by:

getAlgorithmName in interface BlockCipher

Returns:

the name of the algorithm the cipher implements.

processBlock

public final int processBlock(byte[] in,
                              int inOff,
                              byte[] out,
                              int outOff)

Description copied from interface: BlockCipher

Process one block of input from the array in and write it to the out array.

Specified by:

processBlock in interface BlockCipher

Parameters:

in - the array containing the input data.

inOff - offset into the in array the data starts at.

out - the array the output data will be copied into.

outOff - the offset into the out array the output will start at.

Returns:

the number of bytes processed and produced.

reset

public void reset()

Description copied from interface: BlockCipher

Reset the cipher. After resetting the cipher is in the same state as it was after the last init (if there was one).

Specified by:

reset in interface BlockCipher

getBlockSize

public int getBlockSize()

Description copied from interface: BlockCipher

Return the block size for this cipher (in bytes).

Specified by:

getBlockSize in interface BlockCipher

Returns:

the block size for this cipher in bytes.

F

private int F(int x)

processTable

private void processTable(int xl,
                          int xr,
                          int[] table)

apply the encryption cycle to each value pair in the table.

setKey

private void setKey(byte[] key)

encryptBlock

private void encryptBlock(byte[] src,
                          int srcIndex,
                          byte[] dst,
                          int dstIndex)

Encrypt the given input starting at the given offset and place the result in the provided buffer starting at the given offset. The input will be an exact multiple of our blocksize.

decryptBlock

private void decryptBlock(byte[] src,
                          int srcIndex,
                          byte[] dst,
                          int dstIndex)

Decrypt the given input starting at the given offset and place the result in the provided buffer starting at the given offset. The input will be an exact multiple of our blocksize.

BytesTo32bits

private int BytesTo32bits(byte[] b,
                          int i)

Bits32ToBytes

private void Bits32ToBytes(int in,
                           byte[] b,
                           int offset)