Package org.bouncycastle.crypto.paddings

Class TBCPadding

java.lang.Object

org.bouncycastle.crypto.paddings.TBCPadding

All Implemented Interfaces:

BlockCipherPadding

public class TBCPadding
extends Object
implements BlockCipherPadding

A padder that adds Trailing-Bit-Compliment padding to a block.

This padding pads the block out with the compliment of the last bit of the plain text.

Constructor Summary

Constructors

Constructor	Description
TBCPadding()

Method Summary

Modifier and Type	Method	Description
int	addPadding(byte[] in, int inOff)	add the pad bytes to the passed in block, returning the number of bytes added.
String	getPaddingName()	Return the name of the algorithm the padder implements.
void	init(SecureRandom random)	Initialise the padder.
int	padCount(byte[] in)	return the number of pad bytes present in the block.

Methods inherited from class java.lang.Object

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

Constructor Details

TBCPadding

public TBCPadding()

Method Details

init

public void init(SecureRandom random) throws IllegalArgumentException

Initialise the padder.

Specified by:

init in interface BlockCipherPadding

Parameters:

random - - a SecureRandom if available.

Throws:

IllegalArgumentException

getPaddingName

public String getPaddingName()

Return the name of the algorithm the padder implements.

Specified by:

getPaddingName in interface BlockCipherPadding

Returns:

the name of the algorithm the padder implements.

addPadding

public int addPadding(byte[] in, int inOff)

add the pad bytes to the passed in block, returning the number of bytes added.

Note: this assumes that the last block of plain text is always passed to it inside in. i.e. if inOff is zero, indicating the entire block is to be overwritten with padding the value of in should be the same as the last block of plain text.

Specified by:

addPadding in interface BlockCipherPadding

padCount

public int padCount(byte[] in) throws InvalidCipherTextException

return the number of pad bytes present in the block.

Specified by:

padCount in interface BlockCipherPadding

Throws:

InvalidCipherTextException - if the padding is badly formed or invalid.