Class javax.crypto.spec.DESKeySpec
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Class javax.crypto.spec.DESKeySpec

java.lang.Object
   |
   +----javax.crypto.spec.DESKeySpec

public class DESKeySpec
extends Object
implements KeySpec
A class that provides a specification for a DES key.
See Also:
Key, KeyFactory, KeySpec

Variable Index

 o DES_KEY_LEN
 o ident

Constructor Index

 o DESKeySpec(byte[])
Uses the first 8 bytes in key as the key material for the DES key
 o DESKeySpec(byte[], int)
Uses the first 8 bytes in key, beginning at offset, as the key material for the DES key.

Method Index

 o getKey()
Returns the DES key material.
 o isParityAdjusted(byte[], int)
Checks if the given DES key, starting at offset, is parity-adjusted.
 o isWeak(byte[], int)
DES has a number of weak keys.

Variables

 o ident
  public final static String ident
 o DES_KEY_LEN
  public final static int DES_KEY_LEN

Constructors

 o DESKeySpec
  public DESKeySpec(byte key[]) throws InvalidKeyException
Uses the first 8 bytes in key as the key material for the DES key
Parameters:
key - the buffer with the DES key material.
Throws: InvalidKeyException
if the given key material is shorter than 8 bytes.
 o DESKeySpec
  public DESKeySpec(byte key[],
                    int offset) throws InvalidKeyException
Uses the first 8 bytes in key, beginning at offset, as the key material for the DES key.
Parameters:
key - the buffer with the DES key material.
offset - the offset in key, where the DES key material starts.
Throws: InvalidKeyException
if the given key material, starting at offset, is shorter than 8 bytes.

Methods

 o getKey
  public byte[] getKey()
Returns the DES key material.
Returns:
the DES key material.
 o isParityAdjusted
  public static boolean isParityAdjusted(byte key[],
                                         int offset) throws InvalidKeyException
Checks if the given DES key, starting at offset, is parity-adjusted.
Parameters:
key - the DES key material.
offset - the offset in key, where the DES key material starts.
Returns:
true if the given DES key material is parity-adjusted, false otherwise.
Throws: InvalidKeyException
if the given key material, starting at offset, is shorter than 8 bytes.
 o isWeak
  public static boolean isWeak(byte key[],
                               int offset) throws InvalidKeyException
DES has a number of weak keys. This method will check if the given DES key material is weak or semi-weak.

See "Applied Cryptography" by Bruce Schneier for more information.

Returns:
true if the given DES key material is weak or semi-weak, false otherwise.
Throws: InvalidKeyException
if the given key material, starting at offset, is shorter than 8 bytes.

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