gnu.crypto.cipher

Class NullCipher

Implemented Interfaces:
Cloneable, IBlockCipher, IBlockCipherSpi

public final class NullCipher
extends BaseCipher

The implementation of a Null block cipher.

This cipher does not alter its input at all, claims to process block sizes 128-, 192- and 256-bit long, and key sizes from 64- to 512-bit in 8-bit increments.

Version:
$Revision: 1.9 $

Field Summary

Fields inherited from class gnu.crypto.cipher.BaseCipher

currentBlockSize, currentKey, defaultBlockSize, defaultKeySize, lock, name

Fields inherited from interface gnu.crypto.cipher.IBlockCipher

CIPHER_BLOCK_SIZE, KEY_MATERIAL

Constructor Summary

NullCipher()
Trivial 0-arguments constructor.

Method Summary

Iterator
blockSizes()
Returns an Iterator over the supported block sizes.
Object
clone()
void
decrypt(byte[] in, int i, byte[] out, int j, Object k, int bs)
Decrypts exactly one block of ciphertext.
void
encrypt(byte[] in, int i, byte[] out, int j, Object k, int bs)
Encrypts exactly one block of plaintext.
Iterator
keySizes()
Returns an Iterator over the supported key sizes.
Object
makeKey(byte[] uk, int bs)
Expands a user-supplied key material into a session key for a designated block size.
boolean
selfTest()
A correctness test that consists of basic symmetric encryption / decryption test(s) for all supported block and key sizes, as well as one (1) variable key Known Answer Test (KAT).

Methods inherited from class gnu.crypto.cipher.BaseCipher

clone, currentBlockSize, decryptBlock, defaultBlockSize, defaultKeySize, encryptBlock, init, name, reset, selfTest, testKat, testKat

Constructor Details

NullCipher

public NullCipher()
Trivial 0-arguments constructor.

Method Details

blockSizes

public Iterator blockSizes()
Returns an Iterator over the supported block sizes. Each element returned by this object is a Integer.
Specified by:
blockSizes in interface IBlockCipher
blockSizes in interface IBlockCipherSpi
Returns:
an Iterator over the supported block sizes.

clone

public Object clone()
Specified by:
clone in interface IBlockCipher
Overrides:
clone in interface BaseCipher

decrypt

public void decrypt(byte[] in,
                    int i,
                    byte[] out,
                    int j,
                    Object k,
                    int bs)
Decrypts exactly one block of ciphertext.
Specified by:
decrypt in interface IBlockCipherSpi
Parameters:
in - the ciphertext.
out - the plaintext.
k - the session key to use.
bs - the block size to use.

encrypt

public void encrypt(byte[] in,
                    int i,
                    byte[] out,
                    int j,
                    Object k,
                    int bs)
Encrypts exactly one block of plaintext.
Specified by:
encrypt in interface IBlockCipherSpi
Parameters:
in - the plaintext.
out - the ciphertext.
k - the session key to use.
bs - the block size to use.

keySizes

public Iterator keySizes()
Returns an Iterator over the supported key sizes. Each element returned by this object is a Integer.
Specified by:
keySizes in interface IBlockCipher
keySizes in interface IBlockCipherSpi
Returns:
an Iterator over the supported key sizes.

makeKey

public Object makeKey(byte[] uk,
                      int bs)
            throws InvalidKeyException
Expands a user-supplied key material into a session key for a designated block size.
Specified by:
makeKey in interface IBlockCipherSpi
Parameters:
bs - the desired block size in bytes.
Returns:
an Object encapsulating the session key.

selfTest

public boolean selfTest()
A correctness test that consists of basic symmetric encryption / decryption test(s) for all supported block and key sizes, as well as one (1) variable key Known Answer Test (KAT).
Specified by:
selfTest in interface IBlockCipher
selfTest in interface IBlockCipherSpi
Overrides:
selfTest in interface BaseCipher
Returns:
true if the implementation passes simple correctness tests. Returns false otherwise.

Copyright © 2001, 2002, 2003 Free Software Foundation, Inc. All Rights Reserved.