cz.d1x.dxcrypto.encryption.crypto

Class SymmetricAlgorithmBuilder

java.lang.Object

cz.d1x.dxcrypto.encryption.crypto.SymmetricAlgorithmBuilder

All Implemented Interfaces:

EncryptionAlgorithmBuilder

Direct Known Subclasses:

AESBuilder, TripleDESBuilder

public abstract class SymmetricAlgorithmBuilder
extends Object
implements EncryptionAlgorithmBuilder

Base builder for symmetric key algorithms.

Author:

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

See Also:

SymmetricAlgorithm

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SymmetricAlgorithmBuilder(byte[] keyPassword)
protected	SymmetricAlgorithmBuilder(CryptoKeyFactory customKeyFactory)
protected	SymmetricAlgorithmBuilder(String keyPassword)

Method Summary

Modifier and Type	Method and Description
EncryptionAlgorithm	build() Builds a new instance of encryption algorithm.
SymmetricAlgorithmBuilder	combineAlgorithm(CombineAlgorithm combineAlgorithm) Sets algorithm combining IV and cipher text in output during encryption and splitting from input during decryption.
SymmetricAlgorithmBuilder	encoding(String encoding) Sets encoding for strings in input and output.
protected abstract String	getAlgorithm() Gets a name of algorithm supported by crypto.
protected abstract int	getBlockSize() Gets a block size of cipher (for CBC).
protected abstract int	getKeySize() Gets size of the key.
protected abstract String	getShortAlgorithm() Gets a short name of algorithm supported by crypto keys.
SymmetricAlgorithmBuilder	keyHashIterations(int keyHashIterations) Sets number of keyHashIterations of hashing for key derivation.
SymmetricAlgorithmBuilder	keySalt(byte[] keySalt) Sets salt for key derivation.
SymmetricAlgorithmBuilder	keySalt(String keySalt) Sets salt for key derivation.

Methods inherited from class java.lang.Object

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

Constructor Detail

SymmetricAlgorithmBuilder

protected SymmetricAlgorithmBuilder(byte[] keyPassword)

SymmetricAlgorithmBuilder

protected SymmetricAlgorithmBuilder(String keyPassword)

SymmetricAlgorithmBuilder

protected SymmetricAlgorithmBuilder(CryptoKeyFactory customKeyFactory)

Method Detail

getAlgorithm

protected abstract String getAlgorithm()

Gets a name of algorithm supported by crypto.

Returns:

algorithm name

getShortAlgorithm

protected abstract String getShortAlgorithm()

Gets a short name of algorithm supported by crypto keys.

Returns:

algorithm name

getKeySize

protected abstract int getKeySize()

Gets size of the key.

Returns:

size of key

getBlockSize

protected abstract int getBlockSize()

Gets a block size of cipher (for CBC).

Returns:

cipher block size

keySalt

public SymmetricAlgorithmBuilder keySalt(byte[] keySalt)

Sets salt for key derivation. Recommended length is at least 8 bytes.

Parameters:

keySalt - salt to be set

Returns:

this instance

keySalt

public SymmetricAlgorithmBuilder keySalt(String keySalt)

Sets salt for key derivation. Recommended length is at least 8 bytes.

Parameters:

keySalt - salt to be set

Returns:

this instance

keyHashIterations

public SymmetricAlgorithmBuilder keyHashIterations(int keyHashIterations)

Sets number of keyHashIterations of hashing for key derivation. Recommended count is at least 1000.

Parameters:

keyHashIterations - number of keyHashIterations

Returns:

this instance

combineAlgorithm

public SymmetricAlgorithmBuilder combineAlgorithm(CombineAlgorithm combineAlgorithm)

Sets algorithm combining IV and cipher text in output during encryption and splitting from input during decryption.

Parameters:

combineAlgorithm - combine algorithm for IV and cipher text

Returns:

this instance

encoding

public SymmetricAlgorithmBuilder encoding(String encoding)

Sets encoding for strings in input and output.

Parameters:

encoding - encoding to be set

Returns:

this instance

build

public EncryptionAlgorithm build()
                          throws EncryptionException

Description copied from interface: EncryptionAlgorithmBuilder

Builds a new instance of encryption algorithm.

Specified by:

build in interface EncryptionAlgorithmBuilder

Returns:

algorithm instance

Throws:

EncryptionException - possible exception when encryption algorithm cannot be built