xjava.security

Interface Padding

Known Implementing Classes:
OneAndZeroes, PaddingScheme, PKCS5, PKCS7

public interface Padding

Padding is the interface defined by JavaSoft's JCE to be implemented by classes that provide a general-purpose padding scheme. It is not used in IJCE, for several reasons:

This interface is included in IJCE only so that classes that use it will not fail with an unrecoverable linking error. The abstract class PaddingScheme should be used instead.

Copyright © 1997 Systemics Ltd on behalf of the Cryptix Development Team.
All rights reserved.

$Revision: 1.2 $

Author:
David Hopwood
Since:
IJCE 1.0.0
See Also:
java.security.PaddingScheme

Method Summary

int
pad(in[] , int off, int len)
Pads a given array of bytes.
int
padLength(int len)
Returns the absolute value of the increase in size that a padding operation would cause on input data of a given length.
String
paddingScheme()
Returns the standard name of the padding scheme implemented.
int
unpad(in[] , int off, int len)
Given the specified subarray of bytes that includes padding bytes, returns the index indicating where padding starts.

Method Details

pad

public int pad(in[] ,
               int off,
               int len)
Pads a given array of bytes. The padded bytes are written to the same buffer that is used for input ("in").
Parameters:
off - the offset into the in buffer of the first byte in the group of bytes to be padded.
len - the number of bytes from the in buffer, starting at off, that need to be padded.
Returns:
the number of padding bytes written.
See Also:
java.security.Cipher.blockSize

padLength

public int padLength(int len)
Returns the absolute value of the increase in size that a padding operation would cause on input data of a given length.
Parameters:
len - the length of the data which is to be padded.
Returns:
the absolute value of the increase in size that a padding operation would cause on input data of the specified length.

paddingScheme

public String paddingScheme()
Returns:
the standard name of the padding scheme, such as "PKCS#5".

unpad

public int unpad(in[] ,
                 int off,
                 int len)
Given the specified subarray of bytes that includes padding bytes, returns the index indicating where padding starts.
Parameters:
off - the starting offset into the in buffer of the bytes to be checked to determine where padding starts.
len - the number of bytes from the in buffer to check, starting at offset off.
Returns:
the index into the in buffer indicating where the padding starts.