er.extensions.crypting

Class ERXAbstractBlowfishCrypter

java.lang.Object

er.extensions.crypting.ERXAbstractBlowfishCrypter

All Implemented Interfaces:

ERXCrypterInterface

Direct Known Subclasses:

ERXBlowfishCrypter, ERXKeyStoreBlowfishCrypter

public abstract class ERXAbstractBlowfishCrypter
extends Object
implements ERXCrypterInterface

ERXAbstractBlowfishCrypter is a blowfish implementation of the crypter interface that allows subclasses to override the source of the blowfish key. The blowfish cipher is a two-way cipher meaning the original string that was encrypted can be retrieved. The way that this version of the blowfish cipher is encrypted it is safe to use as a form value.

Author:

mschrag

Constructor Summary

Constructors

Constructor and Description
ERXAbstractBlowfishCrypter()

Method Summary

Modifier and Type	Method and Description
int	blockSize() Returns the block size for this cipher.
protected Cipher	createBlowfishCipher(int mode) Creates a blowfish cipher for a given mode.
String	decrypt(String cryptedText) Decodes a blowfish encoded string.
protected Cipher	decryptCipher() Method used to return the shared instance of the blowfish decryption cipher.
String	encrypt(String clearText) Blowfish encodes a given string using the secret key specified in the System property: ERBlowfishCipherKey.
protected Cipher	encryptCipher() Method used to return the shared instance of the blowfish encryption cipher.
protected abstract Key	secretBlowfishKey() Returns the secret key to use for this cipher.
void	setBlockSize(int blockSize) Sets the block size to use for this cipher.

Methods inherited from class java.lang.Object

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

Constructor Detail

ERXAbstractBlowfishCrypter

public ERXAbstractBlowfishCrypter()

Method Detail

setBlockSize

public void setBlockSize(int blockSize)

Sets the block size to use for this cipher.

Parameters:

blockSize - the block size to use for this cipher

blockSize

public int blockSize()

Returns the block size for this cipher.

Returns:

the block size for this cipher

secretBlowfishKey

protected abstract Key secretBlowfishKey()
                                  throws Exception

Returns the secret key to use for this cipher.

Returns:

a secret key for the blowfish cipher

Throws:

Exception

createBlowfishCipher

protected Cipher createBlowfishCipher(int mode)

Creates a blowfish cipher for a given mode. The two possible modes for a blowfish cipher are: ENCRYPT and DECRYPT.

Parameters:

mode - of the cipher (encrypting or decrypting)

Returns:

a blowfish cipher initialized with the given mode and with the secretKey from the above method.

encryptCipher

protected Cipher encryptCipher()

Method used to return the shared instance of the blowfish encryption cipher.

Returns:

blowfish encryption cipher

decryptCipher

protected Cipher decryptCipher()

Method used to return the shared instance of the blowfish decryption cipher.

Returns:

blowfish decryption cipher

decrypt

public String decrypt(String cryptedText)

Decodes a blowfish encoded string. Note that the originally encoded string should have been encoded with the same secret key as is used for the decoding cipher or else you are going to get garbage. To encode a string have a look at blowfishEncode.

Specified by:

decrypt in interface ERXCrypterInterface

Parameters:

cryptedText - blowfish encoded string to be decoded

Returns:

decode clear text string

encrypt

public String encrypt(String clearText)

Blowfish encodes a given string using the secret key specified in the System property: ERBlowfishCipherKey. The blowfish cipher is a two way cipher meaning that given the secret key you can de-cipher what the original string is. For one-way encryption look at methods dealing with the Sha alogrithm. To decode a blowfish encoded string use the method: blowfishDecode. The resultant string from encoding a string is safe for use in urls and cookies.

Specified by:

encrypt in interface ERXCrypterInterface

Parameters:

clearText - string to be encrypted

Returns:

encrypted string