xjava.security
public interface ExtendedKeyGenerator
This interface provides a standard API for KeyGenerators that implement the above features.
Copyright © 1997
Systemics Ltd on behalf of the
Cryptix Development Team.
All rights reserved.
$Revision: 1.2 $
Since: IJCE 1.0.1
Method Summary | |
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SecretKey | generateKey()
Generates a key. |
SecretKey | generateKey(byte[] data)
Generates a key from an encoded byte array. |
int | getDefaultKeyLength()
Returns the key length that will be used by
generateKey() to create new random keys. |
int | getMaximumKeyLength()
Returns the maximum useful key length for this algorithm. |
int | getMinimumKeyLength()
Returns the minimum key length for this algorithm. |
void | initialize(SecureRandom random)
Initializes the key generator.
|
void | initialize(SecureRandom random, int length)
Initializes the key generator, and sets a specific key length
for use with algorithms that allow variable-length keys.
|
boolean | isValidKeyLength(int length)
Returns true iff length is a valid key length (in bytes)
for this algorithm. |
boolean | isWeakAllowed()
Returns true if this object is allowed to generate weak and
semi-weak keys; false otherwise. |
void | setWeakAllowed(boolean allowWeak)
Sets whether this object is allowed to generate weak and
semi-weak keys.
|
If a source of random bytes has not been set using one of the
initialize
methods, new SecureRandom()
will be used.
Returns: the new key.
The encoded key bytes may differ from data in order to make sure that they represent a valid key. For example, if keys for this algorithm conventionally include parity bits, those bits will be set correctly. For most algorithms, data is used unchanged.
Parameters: data user supplied raw-encoded data from which a secret key will be generated.
Returns: the new key.
Throws: NullPointerException if data == null WeakKeyException if isWeakAllowed() is false, and data represents a weak key for this algorithm. InvalidKeyException if the length of data is not valid for this algorithm.
generateKey()
to create new random keys. This is
either the default key length determined by the KeyGenerator
for this algorithm, or the length set using
initialize(SecureRandom random, int length)
.Parameters: random the source of randomness for this generator.
The length parameter only affects randomly generated
keys (i.e. the generateKey()
method without
parameters).
Parameters: random the source of randomness for this generator. length the desired key length in bytes.
Throws: IllegalArgumentException if length is not valid for this algorithm.
Parameters: allowWeak true if weak/semi-weak keys are allowed.