Class OpenSslGaloisCounterMode

java.lang.Object

org.apache.commons.crypto.cipher.AbstractOpenSslFeedbackCipher

org.apache.commons.crypto.cipher.OpenSslGaloisCounterMode

final class OpenSslGaloisCounterMode
extends AbstractOpenSslFeedbackCipher

This class do the real work(Encryption/Decryption/Authentication) for the authenticated mode: GCM. It calls the OpenSSL API to implement the JCE-like behavior

Since:

1.1

Field Summary

Fields

Modifier and Type	Field	Description
private ByteArrayOutputStream	aadBuffer
(package private) static final int	DEFAULT_TAG_LEN
private ByteArrayOutputStream	inBuffer
private int	tagBitLen

Fields inherited from class AbstractOpenSslFeedbackCipher

algorithmMode, cipherMode, context, padding

Constructor Summary

Constructors

Constructor	Description
OpenSslGaloisCounterMode(long context, int algorithmMode, int padding)

Method Summary

Modifier and Type	Method	Description
void	clean()
int	doFinal(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)
int	doFinal(ByteBuffer input, ByteBuffer output)
private int	evpCipherCtxCtrl(long context, int type, int arg, ByteBuffer data)	Wraps of OpenSslNative.ctrl(long context, int type, int arg, byte[] data) Since native interface EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr) is generic, it may set/get any native char or long type to the data buffer(ptr).
private int	getTagLen()
void	init(int mode, byte[] key, AlgorithmParameterSpec params)
private void	processAAD()
int	update(byte[] input, int inputOffset, int inputLen, byte[] output, int outputOffset)
int	update(ByteBuffer input, ByteBuffer output)
void	updateAAD(byte[] aad)

Methods inherited from class AbstractOpenSslFeedbackCipher

checkState

Methods inherited from class Object

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

Field Details

DEFAULT_TAG_LEN

static final int DEFAULT_TAG_LEN

See Also:

• Constant Field Values

aadBuffer

private ByteArrayOutputStream aadBuffer

tagBitLen

private int tagBitLen

inBuffer

private ByteArrayOutputStream inBuffer

Constructor Details

OpenSslGaloisCounterMode

public OpenSslGaloisCounterMode(long context,
 int algorithmMode,
 int padding)

Method Details

clean

public void clean()

Overrides:

clean in class AbstractOpenSslFeedbackCipher

doFinal

public int doFinal(byte[] input,
 int inputOffset,
 int inputLen,
 byte[] output,
 int outputOffset)
            throws ShortBufferException,
IllegalBlockSizeException,
BadPaddingException

Specified by:

doFinal in class AbstractOpenSslFeedbackCipher

Throws:

ShortBufferException

IllegalBlockSizeException

BadPaddingException

doFinal

public int doFinal(ByteBuffer input,
 ByteBuffer output)
            throws ShortBufferException,
IllegalBlockSizeException,
BadPaddingException

Specified by:

doFinal in class AbstractOpenSslFeedbackCipher

Throws:

ShortBufferException

IllegalBlockSizeException

BadPaddingException

evpCipherCtxCtrl

private int evpCipherCtxCtrl(long context,
 int type,
 int arg,
 ByteBuffer data)

Wraps of OpenSslNative.ctrl(long context, int type, int arg, byte[] data) Since native interface EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr) is generic, it may set/get any native char or long type to the data buffer(ptr). Here we use ByteBuffer and set nativeOrder to handle the endianness.

Parameters:

context - The cipher context address

type - CtrlValues

arg - argument like a tag length

data - byte buffer or null

Returns:

return 0 if there is any error, else return 1.

getTagLen

private int getTagLen()

init

public void init(int mode,
 byte[] key,
 AlgorithmParameterSpec params)
          throws InvalidAlgorithmParameterException

Specified by:

init in class AbstractOpenSslFeedbackCipher

Throws:

InvalidAlgorithmParameterException

processAAD

private void processAAD()

update

public int update(byte[] input,
 int inputOffset,
 int inputLen,
 byte[] output,
 int outputOffset)
           throws ShortBufferException

Specified by:

update in class AbstractOpenSslFeedbackCipher

Throws:

ShortBufferException

update

public int update(ByteBuffer input,
 ByteBuffer output)
           throws ShortBufferException

Specified by:

update in class AbstractOpenSslFeedbackCipher

Throws:

ShortBufferException

updateAAD

public void updateAAD(byte[] aad)

Specified by:

updateAAD in class AbstractOpenSslFeedbackCipher