Package org.apache.sshd.common.cipher

Class BaseCipher

java.lang.Object

org.apache.sshd.common.cipher.BaseCipher

All Implemented Interfaces:

AlgorithmNameProvider, Cipher, CipherInformation, KeySizeIndicator

Direct Known Subclasses:

BaseGCMCipher, BaseRC4Cipher

public class BaseCipher
extends Object
implements Cipher

Base class for all Cipher implementations delegating to the JCE provider.

Author:

Apache MINA SSHD Project

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.sshd.common.cipher.Cipher

Cipher.Mode

Constructor Summary

Constructors

Constructor	Description
BaseCipher(int ivsize, int authSize, int kdfSize, String algorithm, int keySize, String transformation, int blkSize)

Method Summary

Modifier and Type	Method	Description
protected Cipher	createCipherInstance(Cipher.Mode mode, byte[] key, byte[] iv)
String	getAlgorithm()
int	getAuthenticationTagSize()
int	getCipherBlockSize()
protected Cipher	getCipherInstance()
int	getIVSize()
int	getKdfSize()
int	getKeySize()
String	getTransformation()
void	init(Cipher.Mode mode, byte[] key, byte[] iv)	Initialize the cipher for encryption or decryption with the given key and initialization vector
protected byte[]	initializeIVData(Cipher.Mode mode, byte[] iv, int reqLen)
protected byte[]	initializeKeyData(Cipher.Mode mode, byte[] key, int reqLen)
protected static byte[]	resize(byte[] data, int size)
String	toString()
void	update(byte[] input, int inputOffset, int inputLen)	Performs in-place encryption or decryption on the given data.
void	updateAAD(byte[] data, int offset, int length)	Adds the provided input data as additional authenticated data during encryption or decryption.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.sshd.common.cipher.Cipher

update, updateAAD, updateWithAAD

Constructor Detail

BaseCipher

public BaseCipher(int ivsize,
                  int authSize,
                  int kdfSize,
                  String algorithm,
                  int keySize,
                  String transformation,
                  int blkSize)

Method Detail

getAlgorithm

public String getAlgorithm()

Specified by:

getAlgorithm in interface AlgorithmNameProvider

getKeySize

public int getKeySize()

Specified by:

getKeySize in interface KeySizeIndicator

Returns:

The number of bits used in the key

getTransformation

public String getTransformation()

Specified by:

getTransformation in interface CipherInformation

Returns:

The actual transformation used - e.g., AES/CBC/NoPadding

getIVSize

public int getIVSize()

Specified by:

getIVSize in interface CipherInformation

Returns:

Size of the initialization vector (in bytes)

getAuthenticationTagSize

public int getAuthenticationTagSize()

Specified by:

getAuthenticationTagSize in interface CipherInformation

Returns:

Size of the authentication tag (AT) in bytes or 0 if this cipher does not support authentication

getKdfSize

public int getKdfSize()

Specified by:

getKdfSize in interface CipherInformation

Returns:

The block size (in bytes) used to derive the secret key for this cipher

getCipherBlockSize

public int getCipherBlockSize()

Specified by:

getCipherBlockSize in interface CipherInformation

Returns:

Size of block data used by the cipher (in bytes). For stream ciphers this value is (currently) used to indicate some average work buffer size to be used for the automatic re-keying mechanism described in RFC 4253 - Section 9

init

public void init(Cipher.Mode mode,
                 byte[] key,
                 byte[] iv)
          throws Exception

Description copied from interface: Cipher

Initialize the cipher for encryption or decryption with the given key and initialization vector

Specified by:

init in interface Cipher

Parameters:

mode - Encrypt/Decrypt initialization

key - Key bytes

iv - Initialization vector bytes

Throws:

Exception - If failed to initialize

getCipherInstance

protected Cipher getCipherInstance()

createCipherInstance

protected Cipher createCipherInstance(Cipher.Mode mode,
                                      byte[] key,
                                      byte[] iv)
                               throws Exception

Throws:

Exception

initializeKeyData

protected byte[] initializeKeyData(Cipher.Mode mode,
                                   byte[] key,
                                   int reqLen)

initializeIVData

protected byte[] initializeIVData(Cipher.Mode mode,
                                  byte[] iv,
                                  int reqLen)

update

public void update(byte[] input,
                   int inputOffset,
                   int inputLen)
            throws Exception

Description copied from interface: Cipher

Performs in-place encryption or decryption on the given data.

Specified by:

update in interface Cipher

Parameters:

input - The input/output bytes

inputOffset - The offset of the data in the data buffer

inputLen - The number of bytes to update - starting at the given offset

Throws:

Exception - If failed to execute

updateAAD

public void updateAAD(byte[] data,
                      int offset,
                      int length)
               throws Exception

Description copied from interface: Cipher

Adds the provided input data as additional authenticated data during encryption or decryption.

Specified by:

updateAAD in interface Cipher

Parameters:

data - The additional data to authenticate

offset - The offset of the additional data in the buffer

length - The number of bytes in the buffer to use for authentication

Throws:

Exception - If failed to execute

resize

protected static byte[] resize(byte[] data,
                               int size)

toString

public String toString()

Overrides:

toString in class Object