core.crypto
Class Symmetric

java.lang.Object
  core.crypto.Symmetric

public class Symmetric
extends Object

A static class Providing all symmetric cipher Operations

  Copyright (c) 2006 Sebastian Erdweg
  Copyright (c) 2006 Dominik Schulz
  Copyright (c) 2006 Florian Lindner
  Copyright (c) 2006 Betim Berjani
  
  This file is part of FlexiCrypt.

  FlexiCrypt is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  FlexiCrypt is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.
  
  You should have received a copy of the GNU General Public License
  along with FlexiCrypt; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  

Author:

Dominik, Sebastian

Field Summary

static String	SECRET_KEY_END_TAG
static String	SECRET_KEY_START_TAG

Method Summary

static byte[]	decrypt(byte[] in, SecretKey secretKey, int buffersize)
static void	decrypt(File inputFile, File outputFile, SecretKey secretKey, int buffersize)
static void	decrypt(InputStream fis, OutputStream fos, SecretKey secretKey, int buffersize)
static String	decrypt(String in, SecretKey secretKey, int buffersize)
static byte[]	encrypt(byte[] in, SecretKey secretKey, int buffersize)
static void	encrypt(File inputFile, File outputFile, SecretKey secretKey, int buffersize)
static void	encrypt(InputStream fis, OutputStream fos, SecretKey secretKey, int buffersize)
static String	encrypt(String in, SecretKey secretKey, int buffersize)
static SecretKey	getNewKey(String algorithm, int keySize) Erzeugt einen neuen symmetrischen Schlüssel
static SecretKey	getNewPBEKey(char[] password) Constructs a passphrase based encryption key by computing its hashvalue 5 times with MD5 and then creating an RC6 key out of it.
static HashMap<String,Set<Integer>>	getValidServices() Creates a set of valid symmetric algorithms

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

SECRET_KEY_START_TAG

public static final String SECRET_KEY_START_TAG

See Also:

Constant Field Values

SECRET_KEY_END_TAG

public static final String SECRET_KEY_END_TAG

See Also:

Constant Field Values

Method Detail

decrypt

public static byte[] decrypt(byte[] in,
                             SecretKey secretKey,
                             int buffersize)
                      throws InvalidKeyException,
                             NoSuchPaddingException,
                             NoSuchAlgorithmException,
                             IOException,
                             InterruptedException

Parameters:

in -

secretKey -

buffersize -

Returns:

Throws:

InvalidKeyException

NoSuchPaddingException

NoSuchAlgorithmException

IOException

InterruptedException

decrypt

public static String decrypt(String in,
                             SecretKey secretKey,
                             int buffersize)
                      throws InvalidKeyException,
                             NoSuchPaddingException,
                             NoSuchAlgorithmException,
                             IOException,
                             InterruptedException

Parameters:

in -

secretKey -

buffersize -

Returns:

the decrypted string

Throws:

InvalidKeyException

NoSuchPaddingException

NoSuchAlgorithmException

IOException

InterruptedException

decrypt

public static void decrypt(File inputFile,
                           File outputFile,
                           SecretKey secretKey,
                           int buffersize)
                    throws FileNotFoundException,
                           NoSuchPaddingException,
                           NoSuchAlgorithmException,
                           InvalidKeyException,
                           IOException,
                           InterruptedException

Parameters:

inputFile -

outputFile -

secretKey -

buffersize -

Throws:

FileNotFoundException

NoSuchPaddingException

NoSuchAlgorithmException

InvalidKeyException

IOException

InterruptedException

decrypt

public static void decrypt(InputStream fis,
                           OutputStream fos,
                           SecretKey secretKey,
                           int buffersize)
                    throws NoSuchPaddingException,
                           NoSuchAlgorithmException,
                           InvalidKeyException,
                           IOException,
                           InterruptedException

Parameters:

fis -

fos -

secretKey -

buffersize -

Throws:

NoSuchPaddingException

NoSuchAlgorithmException

InvalidKeyException

IOException

InterruptedException

encrypt

public static byte[] encrypt(byte[] in,
                             SecretKey secretKey,
                             int buffersize)
                      throws InvalidKeyException,
                             NoSuchPaddingException,
                             NoSuchAlgorithmException,
                             IOException,
                             InterruptedException

Parameters:

in -

secretKey -

buffersize -

Returns:

the encrypted byte array

Throws:

InvalidKeyException

NoSuchPaddingException

NoSuchAlgorithmException

IOException

InterruptedException

encrypt

public static String encrypt(String in,
                             SecretKey secretKey,
                             int buffersize)
                      throws InvalidKeyException,
                             NoSuchPaddingException,
                             NoSuchAlgorithmException,
                             IOException,
                             InterruptedException

Throws:

InvalidKeyException

NoSuchPaddingException

NoSuchAlgorithmException

IOException

InterruptedException

encrypt

public static void encrypt(File inputFile,
                           File outputFile,
                           SecretKey secretKey,
                           int buffersize)
                    throws FileNotFoundException,
                           NoSuchPaddingException,
                           NoSuchAlgorithmException,
                           InvalidKeyException,
                           IOException,
                           InterruptedException

Parameters:

inputFile -

outputFile -

secretKey -

buffersize -

Throws:

FileNotFoundException

NoSuchPaddingException

NoSuchAlgorithmException

InvalidKeyException

IOException - Encryption using Files

InterruptedException

encrypt

public static void encrypt(InputStream fis,
                           OutputStream fos,
                           SecretKey secretKey,
                           int buffersize)
                    throws NoSuchPaddingException,
                           NoSuchAlgorithmException,
                           InvalidKeyException,
                           IOException,
                           InterruptedException

Parameters:

fis - - The FileInputStream containing the encrypted data

fos - - The FileOutputStrem to write the decrypted data

secretKey - - The secret key (shared secret) used to encrypt the data

buffersize -

Throws:

InterruptedException

BadPaddingException

IllegalBlockSizeException

NoSuchPaddingException

NoSuchAlgorithmException

InvalidKeyException

IOException

getNewKey

public static SecretKey getNewKey(String algorithm,
                                  int keySize)
                           throws NoSuchAlgorithmException

Erzeugt einen neuen symmetrischen Schlüssel

Parameters:

algorithm -

keySize -

Returns:

a new symmetric key with the given keysize and algorithm

Throws:

NoSuchAlgorithmException

getNewPBEKey

public static SecretKey getNewPBEKey(char[] password)
                              throws NoSuchAlgorithmException,
                                     InvalidAlgorithmParameterException,
                                     InterruptedException,
                                     IOException

Constructs a passphrase based encryption key by computing its hashvalue 5 times with MD5 and then creating an RC6 key out of it.

Parameters:

password -

Returns:

a new SecretKey

Throws:

NoSuchAlgorithmException

IOException

InterruptedException

InvalidAlgorithmParameterException

getValidServices

public static HashMap<String,Set<Integer>> getValidServices()

Creates a set of valid symmetric algorithms

Returns:

a set of valid symmetric algorithms