iaik.me.security.cipher
Class DES

java.lang.Object
  |
  +--iaik.me.security.Cipher
        |
        +--iaik.me.security.cipher.DES

public class DES

extends Cipher

Fields inherited from class iaik.me.security.Cipher

chainingMode, DECRYPT_MODE, ENCRYPT_MODE, iv, mode, MODE_CBC, MODE_ECB

Constructor Summary

DES()
Constructor for the DES cipher.

Method Summary

protected void	cryptBlock(byte[] in, int inOff, byte[] out, int outOff) Encrypt one block.
int[]	getKeyLength() Return the valid key lengths for this cipher.
void	init(int mode, CryptoBag keyb, Object params, SecureRandom random) Initializes this DES cipher with proper key and algorithm parameters, and some random seed.

Methods inherited from class iaik.me.security.Cipher

doFinal, doFinal, extractIV, getBlockSize, getInstance, getIV, init, register, setMode, setPadding, toString, update, updateInternal

Methods inherited from class java.lang.Object

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

Constructor Detail

DES

public DES()

Constructor for the DES cipher. This constructor only internally is used for initializing a DES Cipher. Applications should not call this constructor to get a DES Cipher; they should call one of the Cipher.getInstance factory methods instead.

See Also:

DES, javax.crypto.Cipher#getInstance

Method Detail

getKeyLength

public int[] getKeyLength()

Description copied from class: Cipher

Return the valid key lengths for this cipher. The array will always have four elements, key lengths are specified in bytes. The values identify the length of the key in bytes, not the entropy, i.e. DES returns 8 instead of 7.
[0] is the minimum allowable length (e.g. 1 byte (8 bit) for ARCFOUR).
[1] is the recommended default length (e.g. 16 byte (128 bit) for ARCFOUR).
[2] is the maximum allowable length (e.g. 128 byte (1024 bit) for ARCFOUR).
[3] is increment between key length (e.g. 1 byte (8 bit) for ARCFOUR), 4 byte (32 bit) for AES.
It is assumed that keys are always a integral number of bytes.

Overrides:

getKeyLength in class Cipher

init

public void init(int mode,
                 CryptoBag keyb,
                 Object params,
                 SecureRandom random)
          throws CryptoException

Initializes this DES cipher with proper key and algorithm parameters, and some random seed. Before a cipher object is ready for data processing, it has to be initialized according to the desired cryptographic operation, which is specified by the opmode parameter (either ENCRYPT_MODE or DECCRYPT_MODE).

The format of the key must be "RAW" and the length must be 8 bytes. The algorithm parameters usually will be a IvParameterSpec representing the initialization vector when running DES in CBC, PCBC, OFB or CFB mode.

Overrides:

init in class Cipher

Parameters:

opmode - the operation mode for which this cipher is used (ENCRYPT_MODE or DECRYPT_MODE)

key - the key

params - the algorithm parameters

random - the random seed

Throws:

InvalidKeyException - if the given key is invalid

See Also:

javax.crypto.spec.IvParameterSpec

cryptBlock

protected void cryptBlock(byte[] in,
                          int inOff,
                          byte[] out,
                          int outOff)

Description copied from class: Cipher

Encrypt one block. To be implemented by subclasses.

Overrides:

cryptBlock in class Cipher