javax.crypto.spec
Class DESKeySpec
- java.lang.Object
javax.crypto.spec.DESKeySpec
All implemented interfaces:
java.security.spec.KeySpec
- public class DESKeySpec
- extends java.lang.Object
- implements java.security.spec.KeySpec
Since:
1.4
Version:
1.21, 01/07/04
Author:
Jan Luehe
Field Summary
Modifier and Type | Field and Description |
---|---|
|
DES_KEY_LEN
The constant which defines the length of a DES key in bytes.
|
Constructor Summary
Constructor and Description |
---|
DESKeySpec(byte[] key)
Creates a DESKeySpec object using the first 8 bytes in
key as the key material for the DES key.
|
DESKeySpec(byte[] key,int offset)
Creates a DESKeySpec object using the first 8 bytes in
key , beginning at offset inclusive,
as the key material for the DES key.
|
Method Summary
Modifier and Type | Method and Description |
---|---|
|
getKey()
Returns the DES key material.
|
|
isParityAdjusted(byte[] key,int offset)
Checks if the given DES key material, starting at
offset
inclusive, is parity-adjusted.
|
|
isWeak(byte[] key,int offset)
Checks if the given DES key material is weak or semi-weak.
|
Methods inherited from class java.lang.Object |
---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Field Detail
DES_KEY_LEN
- public static final int DES_KEY_LEN
The constant which defines the length of a DES key in bytes.
See Also:
Constructor Detail
DESKeySpec
- public DESKeySpec(byte[] key)
- throws java.security.InvalidKeyException
Creates a DESKeySpec object using the first 8 bytes in
key
as the key material for the DES key.
The bytes that constitute the DES key are those between
key[0]
and key[7]
inclusive.
Parameters:
key
- the buffer with the DES key material. The first 8 bytes
of the buffer are copied to protect against subsequent modification. Throws:
java.lang.NullPointerException
- if the given key material is
null
java.security.InvalidKeyException
- if the given key material is shorter
than 8 bytes. DESKeySpec
- public DESKeySpec(byte[] key,
- int offset)
- throws java.security.InvalidKeyException
Creates a DESKeySpec object using the first 8 bytes in
key
, beginning at offset
inclusive,
as the key material for the DES key.
The bytes that constitute the DES key are those between
key[offset]
and key[offset+7]
inclusive.
Parameters:
key
- the buffer with the DES key material. The first 8 bytes
of the buffer beginning at offset
inclusive are copied
to protect against subsequent modification. offset
- the offset in key
, where the DES key
material starts. Throws:
java.lang.NullPointerException
- if the given key material is
null
java.security.InvalidKeyException
- if the given key material, starting at
offset
inclusive, is shorter than 8 bytes. Method Detail
getKey
- public byte[] getKey()
Returns the DES key material.
Returns:
the DES key material. Returns a new array
each time this method is called.
isParityAdjusted
- public static boolean isParityAdjusted( byte[] key,
- int offset)
- throws java.security.InvalidKeyException
Checks if the given DES key material, starting at
offset
inclusive, is parity-adjusted.
Parameters:
key
- the buffer with 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:
java.security.InvalidKeyException
- if the given key material is
null
, or starting at offset
inclusive, is
shorter than 8 bytes. isWeak
- public static boolean isWeak(byte[] key,
- int offset)
- throws java.security.InvalidKeyException
Checks if the given DES key material is weak or semi-weak.
Parameters:
key
- the buffer with the DES key material. offset
- the offset in key
, where the DES key
material starts. Returns:
true if the given DES key material is weak or semi-weak, false
otherwise.
Throws:
java.security.InvalidKeyException
- if the given key material is
null
, or starting at offset
inclusive, is
shorter than 8 bytes.