cz.d1x.dxcrypto.encryption

Class GenericEncryptionAlgorithm

java.lang.Object

cz.d1x.dxcrypto.encryption.GenericEncryptionAlgorithm

All Implemented Interfaces:

EncryptionAlgorithm

public final class GenericEncryptionAlgorithm
extends Object
implements EncryptionAlgorithm

Main implementation for encryption algorithms that have all logic based on passed EncryptionEngine.

The logic is based on whether it is intended for use with or without initialization vector.

• Without IV: It simply calls underlying EncryptionEngine and optionally does encoding/decoding operations.
• With IV: It generates a new initialization vector from given ByteArrayFactory and includes in every message based on used CombiningSplitting. This allows to use one instance for different messages (otherwise it would not be safe to use same combination of key and IV for every message).

This class is immutable and can be considered thread safe. It is not allowed to extend this class to ensure it stays that way.

Author:

Zdenek Obst, zdenek.obst-at-gmail.com

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	GenericEncryptionAlgorithm(EncryptionEngine engine, BytesRepresentation bytesRepresentation, String encoding) Creates a new instance of generic algorithm that does NOT use initialization vector.

Method Summary

Modifier and Type	Method and Description
byte[]	decrypt(byte[] input) Decrypts specified array of bytes.
String	decrypt(String input) Decrypts specified input text using default UTF-8 encoding.
byte[]	encrypt(byte[] input) Encrypts specified array of bytes.
String	encrypt(String input) Encrypts specified input text.

Methods inherited from class java.lang.Object

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

Constructor Detail

GenericEncryptionAlgorithm

protected GenericEncryptionAlgorithm(EncryptionEngine engine,
                                     BytesRepresentation bytesRepresentation,
                                     String encoding)
                              throws EncryptionException

Creates a new instance of generic algorithm that does NOT use initialization vector.

Parameters:

engine - engine for encryption

bytesRepresentation - representation of byte arrays in String

encoding - encoding used for strings

Throws:

EncryptionException - exception when algorithm cannot be created

Method Detail

encrypt

public byte[] encrypt(byte[] input)
               throws EncryptionException

Description copied from interface: EncryptionAlgorithm

Encrypts specified array of bytes.

Specified by:

encrypt in interface EncryptionAlgorithm

Parameters:

input - input bytes to be encrypted

Returns:

encrypted bytes

Throws:

EncryptionException - possible exception when encryption fails

encrypt

public String encrypt(String input)
               throws EncryptionException

Description copied from interface: EncryptionAlgorithm

Encrypts specified input text.

Specified by:

encrypt in interface EncryptionAlgorithm

Parameters:

input - input text to be encrypted

Returns:

encrypted text

Throws:

EncryptionException - possible exception when encryption fails

decrypt

public byte[] decrypt(byte[] input)
               throws EncryptionException

Description copied from interface: EncryptionAlgorithm

Decrypts specified array of bytes.

Specified by:

decrypt in interface EncryptionAlgorithm

Parameters:

input - input bytes to be decrypted

Returns:

decrypted bytes

Throws:

EncryptionException - possible exception when decryption fails

decrypt

public String decrypt(String input)
               throws EncryptionException

Description copied from interface: EncryptionAlgorithm

Decrypts specified input text using default UTF-8 encoding.

Specified by:

decrypt in interface EncryptionAlgorithm

Parameters:

input - input text to be decrypted

Returns:

decrypted text

Throws:

EncryptionException - possible exception when decryption fails