edu.vt.middleware.crypt.symmetric
Class DES

java.lang.Object
  edu.vt.middleware.crypt.AbstractAlgorithm
      edu.vt.middleware.crypt.AbstractEncryptionAlgorithm
          edu.vt.middleware.crypt.symmetric.SymmetricAlgorithm
              edu.vt.middleware.crypt.symmetric.DES

All Implemented Interfaces:

Algorithm, EncryptionAlgorithm

public class DES
extends SymmetricAlgorithm

Provider of symmetric encryption/decryption operations using DES cipher.

Version:

$Revision: 3 $

Author:

Middleware Services

Field Summary

static String	ALGORITHM Algorithm name.
static int	DEFAULT_KEY_LENGTH Default key size for this algorithm in bits.
static int[]	KEY_LENGTHS Available key lengths in bits.

Fields inherited from class edu.vt.middleware.crypt.symmetric.SymmetricAlgorithm

DEFAULT_MODE, DEFAULT_PADDING, iv, paramSpec

Fields inherited from class edu.vt.middleware.crypt.AbstractEncryptionAlgorithm

cipher, cipherMode, key, mode, padding

Fields inherited from class edu.vt.middleware.crypt.AbstractAlgorithm

algorithm, logger, randomByteSize, randomProvider

Constructor Summary

DES()
Creates a default DES symmetric encryption algorithm using CBC mode and PKCS5 padding.

DES(String mode, String padding)
Creates a default DES symmetric encryption algorithm using the given mode and padding style.

Method Summary

int[]	getAllowedKeyLengths() Gets an array of key lengths that are acceptable for the cipher algorithm.
int	getDefaultKeyLength() Gets the default key length for this algorithm.

Methods inherited from class edu.vt.middleware.crypt.symmetric.SymmetricAlgorithm

generateKey, generateKey, generateKey, getAlgorithmParameterSpec, getChunkSize, getMaxKeyLength, getMinKeyLength, getRandomIV, hasIV, isValidKeyLength, newInstance, newInstance, newInstance, newInstance, setIV

Methods inherited from class edu.vt.middleware.crypt.AbstractEncryptionAlgorithm

crypt, crypt, decrypt, decrypt, decrypt, encrypt, encrypt, encrypt, getBlockSize, getCipherMode, getMode, getPadding, init, initCipher, initDecrypt, initEncrypt, setKey, toString

Methods inherited from class edu.vt.middleware.crypt.AbstractAlgorithm

getAlgorithm, getRandomData, setRandomProvider

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.vt.middleware.crypt.Algorithm

getAlgorithm, getRandomData, setRandomProvider

Field Detail

ALGORITHM

public static final String ALGORITHM

Algorithm name.

See Also:

Constant Field Values

DEFAULT_KEY_LENGTH

public static final int DEFAULT_KEY_LENGTH

Default key size for this algorithm in bits.

See Also:

Constant Field Values

KEY_LENGTHS

public static final int[] KEY_LENGTHS

Available key lengths in bits.

Constructor Detail

DES

public DES()

Creates a default DES symmetric encryption algorithm using CBC mode and PKCS5 padding.

DES

public DES(String mode,
           String padding)

Creates a default DES symmetric encryption algorithm using the given mode and padding style.

Parameters:

mode - Cipher mode name.

padding - Cipher padding style name.

Method Detail

getDefaultKeyLength

public int getDefaultKeyLength()

Gets the default key length for this algorithm.

Overrides:

getDefaultKeyLength in class SymmetricAlgorithm

Returns:

Default key length in bits.

getAllowedKeyLengths

public int[] getAllowedKeyLengths()

Gets an array of key lengths that are acceptable for the cipher algorithm. By convention the lengths are returned in descending sort order from longest to shortest. There are some ciphers (e.g. Blowfish) that allow key sizes to be any integral value in a range; in those cases only key sizes that are multiple of the cipher block length are returned. Thus this method always returns lengths that are acceptable, but not necessarily all possible lengths.

Overrides:

getAllowedKeyLengths in class SymmetricAlgorithm

Returns:

Array of key lengths in bits.