uk.org.ogsadai.common.rolemap
Class Cryptography

java.lang.Object
  |
  +--uk.org.ogsadai.common.rolemap.Cryptography

public class Cryptography

extends java.lang.Object

A collection of methods related to encrypting and decrypting strings.

The class uses a password value assumed to be within an ogsadai.password system property.

Author:

The OGSA-DAI Project Team

Field Summary

private static java.lang.String	ALGORITHM
private static java.lang.String	COPYRIGHT_NOTICE
private static int	COUNT
private static java.lang.String	PASSWORD
private static byte[]	SALT

Constructor Summary

Cryptography()

Method Summary

private static byte[]	decode(byte[] string) Base64 decode an array of bytes.
private static byte[]	decrypt(java.lang.String password, byte[] cypherText) Decrypt an array of bytes, using the given password, and return the decrypted bytes.
private static byte[]	decrypt(java.lang.String password, java.lang.String cypherText) Decrypt a string, using the given password, and return the decrypted string as an array of bytes.
private static byte[]	encode(byte[] string) Base64 encode an array of bytes.
private static byte[]	encrypt(java.lang.String password, byte[] plainText) Encrypt an array of bytes, using the given password, and return the encrypted bytes.
private static byte[]	encrypt(java.lang.String password, java.lang.String plainText) Encrypt a string, using the given password, and return the encrypted string as an array of bytes.
private static javax.crypto.Cipher	getCypher(java.lang.String password, int encryptMode) Returns a fully-initialised Cipher object which can be used for encryption or decryption.
static java.lang.String	getPassword() Returns the value of the ogsadai.password system property.
static java.lang.String	scramble(java.lang.String password, byte[] plainText) Encrypts an array of bytes, using a given password, and returns the encrypted bytes as a Base64 encoded string.
static java.lang.String	scramble(java.lang.String password, java.lang.String plainText) Encrypts a string, using a given password, and returns the encrypted text as a Base64 encoded string.
static java.lang.String	unscramble(java.lang.String scrambled) Unencrypts a Base64 encoded string, using the value of the ogsadai.password system property as a password, and returns the unencrypted string.
static java.lang.String	unscramble(java.lang.String password, byte[] scrambled) Unencrypts an array of Base64 encoded bytes, using a given password, and returns the unencrypted bytes as a string.
static java.lang.String	unscramble(java.lang.String password, java.lang.String scrambled) Unencrypts a Base64 encoded string, using a given password, and returns the unencrypted string.

Methods inherited from class java.lang.Object

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

Field Detail

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

See Also:

Constant Field Values

ALGORITHM

private static final java.lang.String ALGORITHM

See Also:

Constant Field Values

SALT

private static final byte[] SALT

COUNT

private static final int COUNT

See Also:

Constant Field Values

PASSWORD

private static final java.lang.String PASSWORD

See Also:

Constant Field Values

Constructor Detail

Cryptography

public Cryptography()

Method Detail

getPassword

public static java.lang.String getPassword()
                                    throws MissingSystemPropertyException

Returns the value of the ogsadai.password system property.

Returns:

the value of the password property.

Throws:

MissingSystemPropertyException - if the property is not set.

scramble

public static java.lang.String scramble(java.lang.String password,
                                        byte[] plainText)
                                 throws CryptographyException

Encrypts an array of bytes, using a given password, and returns the encrypted bytes as a Base64 encoded string.

Parameters:

password - The password to use as a key.

plainText - The bytes to encrypt.

Returns:

the encrypted and Base64 encoded string.

Throws:

CryptographyException - if a problem occurred.

scramble

public static java.lang.String scramble(java.lang.String password,
                                        java.lang.String plainText)
                                 throws CryptographyException

Encrypts a string, using a given password, and returns the encrypted text as a Base64 encoded string.

Parameters:

password - The password to use as a key.

plainText - The string to encrypt.

Returns:

the encrypted and Base64 encoded string.

Throws:

CryptographyException - if a problem occurred.

unscramble

public static java.lang.String unscramble(java.lang.String password,
                                          byte[] scrambled)
                                   throws CryptographyException

Unencrypts an array of Base64 encoded bytes, using a given password, and returns the unencrypted bytes as a string.

Parameters:

password - The password to use as a key.

scrambled - The Base64 encoded and encrypted bytes to decrypt.

Returns:

the decrypted string.

Throws:

CryptographyException - if a problem occurred.

unscramble

public static java.lang.String unscramble(java.lang.String password,
                                          java.lang.String scrambled)
                                   throws CryptographyException

Unencrypts a Base64 encoded string, using a given password, and returns the unencrypted string.

Parameters:

password - The password to use as a key.

scrambled - The Base64 encoded and encrypted string to decrypt.

Returns:

the decrypted string.

Throws:

CryptographyException - if a problem occurred.

unscramble

public static java.lang.String unscramble(java.lang.String scrambled)
                                   throws CryptographyException,
                                          MissingSystemPropertyException

Unencrypts a Base64 encoded string, using the value of the ogsadai.password system property as a password, and returns the unencrypted string.

Parameters:

scrambled - The Base64 encoded and encrypted string to decrypt.

Returns:

the decrypted string.

Throws:

CryptographyException - if a problem occurred.

MissingSystemPropertyException - if the property is not set.

encode

private static byte[] encode(byte[] string)

Base64 encode an array of bytes.

Parameters:

string - The bytes to encode.

Returns:

the encoded bytes.

See Also:

Base64.encode(byte[])

decode

private static byte[] decode(byte[] string)

Base64 decode an array of bytes.

Parameters:

string - The bytes to decode.

Returns:

the decoded bytes

See Also:

Base64.decode(byte[])

decrypt

private static byte[] decrypt(java.lang.String password,
                              byte[] cypherText)
                       throws CryptographyException

Decrypt an array of bytes, using the given password, and return the decrypted bytes.

Parameters:

password - The password to use as a key.

cypherText - The encrypted bytes to decrypt

Returns:

the decrypted bytes.

Throws:

CryptographyException - if a problem occurred.

decrypt

private static byte[] decrypt(java.lang.String password,
                              java.lang.String cypherText)
                       throws CryptographyException

Decrypt a string, using the given password, and return the decrypted string as an array of bytes.

Parameters:

password - The password to use as a key.

cypherText - The encrypted string to decrypt

Returns:

the decrypted bytes.

Throws:

CryptographyException - if a problem occurred.

encrypt

private static byte[] encrypt(java.lang.String password,
                              byte[] plainText)
                       throws CryptographyException

Encrypt an array of bytes, using the given password, and return the encrypted bytes.

Parameters:

password - The password to use as a key.

plainText - The plain text bytes to encrypt

Returns:

the encrypted bytes.

Throws:

CryptographyException - if a problem occurred.

encrypt

private static byte[] encrypt(java.lang.String password,
                              java.lang.String plainText)
                       throws CryptographyException

Encrypt a string, using the given password, and return the encrypted string as an array of bytes.

Parameters:

password - The password to use as a key.

plainText - The plain text string to encrypt

Returns:

the encrypted bytes.

Throws:

CryptographyException - if a problem occurred.

getCypher

private static javax.crypto.Cipher getCypher(java.lang.String password,
                                             int encryptMode)
                                      throws CryptographyException

Returns a fully-initialised Cipher object which can be used for encryption or decryption.

Parameters:

password - The password to use as a key.

encryptMode - Either Cipher.ENCRYPT_MODE or Cipher.DECRYPT_MODE.

Returns:

the initialised Cipher object.

Throws:

CryptographyException - if a problem occurred.