com.jcraft.jsch

Class CipherNone

java.lang.Object

com.jcraft.jsch.CipherNone

All Implemented Interfaces:

Cipher

public class CipherNone
extends Object
implements Cipher

Usually not to be used by applications. An implementation of the Cipher none, i.e. unencrypted transport. This is used during key-exchange until the first real Cipher can be used.

The "none" algorithm specifies that no encryption is to be done. Note that this method provides no confidentiality protection, and it is NOT RECOMMENDED. Some functionality (e.g., password authentication) may be disabled for security reasons if this cipher is chosen.

The implementation here consists mainly of no-ops.

See Also:

RFC 4253, section 6.3 Encryption, RFC 2410, The NULL Encryption Algorithm and Its Use With IPsec

Field Summary

Fields inherited from interface com.jcraft.jsch.Cipher

DECRYPT_MODE, ENCRYPT_MODE

Constructor Summary

Constructors

Constructor and Description
CipherNone()

Method Summary

Modifier and Type	Method and Description
int	getBlockSize() Returns the block size of this algorithm.
int	getIVSize() Returns the size of the identity vector for this cipher.
void	init(int mode, byte[] key, byte[] iv) Initializes the Cipher object for a new encryption or decryption operation.
boolean	isCBC() Checks whether this cipher is in Cipher Block Chaining mode.
void	update(byte[] foo, int s1, int len, byte[] bar, int s2) Encrypts or decrypts some more data.

Methods inherited from class java.lang.Object

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

Constructor Detail

CipherNone

public CipherNone()

Method Detail

getIVSize

public int getIVSize()

Description copied from interface: Cipher

Returns the size of the identity vector for this cipher.

Specified by:

getIVSize in interface Cipher

getBlockSize

public int getBlockSize()

Description copied from interface: Cipher

Returns the block size of this algorithm.

Specified by:

getBlockSize in interface Cipher

init

public void init(int mode,
                 byte[] key,
                 byte[] iv)
          throws Exception

Description copied from interface: Cipher

Initializes the Cipher object for a new encryption or decryption operation.

Specified by:

init in interface Cipher

Parameters:

mode - one of Cipher.ENCRYPT_MODE or Cipher.DECRYPT_MODE.

key - the key to use for the crypting operation.

iv - the initialization vector necessary for operation.

Throws:

Exception

update

public void update(byte[] foo,
                   int s1,
                   int len,
                   byte[] bar,
                   int s2)
            throws Exception

Description copied from interface: Cipher

Encrypts or decrypts some more data.

Specified by:

update in interface Cipher

Parameters:

foo - the array from which the plaintext (for encrypting) or ciphertext (for decrypting) should be taken.

s1 - the position in input at which the data is to be found.

len - the length of the input in bytes. The same number of output bytes will be produced.

bar - the array into which the ciphertext (for encrypting) or plaintext (for decrypting) will be written.

s2 - the position in output from which on the data should be written.

Throws:

Exception

isCBC

public boolean isCBC()

Description copied from interface: Cipher

Checks whether this cipher is in Cipher Block Chaining mode.

Specified by:

isCBC in interface Cipher

Returns:

true if this cipher is in CBC mode, false if this cipher is in some other mode.