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:

BaseRC4Cipher

public class BaseCipher
extends java.lang.Object
implements Cipher

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

Nested Class Summary

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

Cipher.Mode

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.String	algorithm
private int	blkSize
private javax.crypto.Cipher	cipher
private int	ivsize
private int	kdfSize
private int	keySize
private java.lang.String	s
private java.lang.String	transformation

Constructor Summary

Constructors

Constructor and Description
BaseCipher(int ivsize, int kdfSize, java.lang.String algorithm, int keySize, java.lang.String transformation, int blkSize)

Method Summary

Modifier and Type	Method and Description
protected javax.crypto.Cipher	createCipherInstance(Cipher.Mode mode, byte[] key, byte[] iv)
java.lang.String	getAlgorithm()
int	getCipherBlockSize()
protected javax.crypto.Cipher	getCipherInstance()
int	getIVSize()
int	getKdfSize()
int	getKeySize()
java.lang.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)
java.lang.String	toString()
void	update(byte[] input, int inputOffset, int inputLen) Performs in-place encryption or decryption on the given data.

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

checkSupported, update

Field Detail

cipher

private javax.crypto.Cipher cipher

ivsize

private final int ivsize

kdfSize

private final int kdfSize

algorithm

private final java.lang.String algorithm

keySize

private final int keySize

blkSize

private final int blkSize

transformation

private final java.lang.String transformation

s

private java.lang.String s

Constructor Detail

BaseCipher

public BaseCipher(int ivsize,
                  int kdfSize,
                  java.lang.String algorithm,
                  int keySize,
                  java.lang.String transformation,
                  int blkSize)

Method Detail

getAlgorithm

public java.lang.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 java.lang.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)

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 java.lang.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:

java.lang.Exception - If failed to initialize

getCipherInstance

protected javax.crypto.Cipher getCipherInstance()

createCipherInstance

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

Throws:

java.lang.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 java.lang.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:

java.lang.Exception - If failed to execute

resize

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

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object