de.bb.security
Class DES3

java.lang.Object
  |
  +--de.bb.security.BlockCipher
        |
        +--de.bb.security.DES
              |
              +--de.bb.security.DES3

public class DES3

extends DES

The triple-DES encryption method. This is a fairly standard way of increasing the security of DES. You run each block through DES three times, first encrypting with key A, then decrypting with key B, then encrypting with key C.

Fields inherited from class de.bb.security.BlockCipher

blockSize

Constructor Summary

DES3()
Creates a new TripleDes object

Method Summary

void	decrypt(byte[] cipherText, int cipherOff, byte[] clearText, int clearOff) Decrypt one block of bytes.
void	encrypt(byte[] clearText, int clearOff, byte[] cipherText, int cipherOff) Encrypt one block of bytes.
void	setKey(byte[] key) Set the key for encryption and decryption.
void	setKeyUnchecked(byte[] key) Set the key for encryption and decryption.

Methods inherited from class de.bb.security.DES

establishParity, generateKey, isOdd, keyIsWeak, makeKeyData

Methods inherited from class de.bb.security.BlockCipher

blockSize, decryptCBC, decryptCBCAndPadd, decryptECB, encryptCBC, encryptCBCAndPadd, encryptECB, getBufferLength

Methods inherited from class java.lang.Object

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

Constructor Detail

DES3

public DES3()

Creates a new TripleDes object

See Also:

DesCipher, BlockCipher

Method Detail

setKey

public void setKey(byte[] key)

Set the key for encryption and decryption.

Overrides:

setKey in class DES

Parameters:

key - the given key, an array with 16 bytes

setKeyUnchecked

public void setKeyUnchecked(byte[] key)

Set the key for encryption and decryption.

Overrides:

setKeyUnchecked in class DES

Parameters:

key - the given key, an array with 16 bytes

encrypt

public void encrypt(byte[] clearText,
                    int clearOff,
                    byte[] cipherText,
                    int cipherOff)

Encrypt one block of bytes. You may use one byte array as input data and output data, to encrypt in place.

Overrides:

encrypt in class DES

Parameters:

clearText - input data which is encrypted

clearOff - offset into input data

cipherText - output data which is encrypted.

cipherOff - offset into output data

decrypt

public void decrypt(byte[] cipherText,
                    int cipherOff,
                    byte[] clearText,
                    int clearOff)

Decrypt one block of bytes. You may use one byte array as input data and output data, to decrypt in place.

Overrides:

decrypt in class DES

Parameters:

cipherText - output data which is encrypted.

cipherOff - offset into output data

clearText - input data which is encrypted

clearOff - offset into input data