gnu.crypto.hash
Class Sha256Standalone

java.lang.Object
  gnu.crypto.hash.BaseHashStandalone
      gnu.crypto.hash.Sha256Standalone

All Implemented Interfaces:

IMessageDigestStandalone, Cloneable

public class Sha256Standalone
extends BaseHashStandalone

Implementation of SHA2-1 [SHA-256] per the IETF Draft Specification.

References:

1. Descriptions of SHA-256, SHA-384, and SHA-512,
2. http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf

Modified by jrandom@i2p.net to remove unnecessary gnu-crypto dependencies, and renamed from Sha256 to avoid conflicts with JVMs using gnu-crypto as their JCE provider. WARNING - DEPRECATED - Use SHA256Generator.getDigestInstance() to get a MessageDigest that will be faster in almost all cases. See SHA256Generator for more information.

Version:

$Revision: 1.2 $

Field Summary

Fields inherited from class gnu.crypto.hash.BaseHashStandalone

blockSize, buffer, count, hashSize, name

Constructor Summary

Sha256Standalone()
Trivial 0-arguments constructor.

Method Summary

Object	clone() Returns a clone copy of this instance.
protected byte[]	getResult() Constructs the result from the contents of the current context.
protected byte[]	padBuffer() Returns the byte array to use as padding before completing a hash operation.
protected void	resetContext() Resets the instance for future re-use.
boolean	selfTest() A basic test.
protected void	transform(byte[] in, int offset) The block digest transformation per se.

Methods inherited from class gnu.crypto.hash.BaseHashStandalone

blockSize, digest, hashSize, name, reset, update, update, update

Methods inherited from class java.lang.Object

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

Constructor Detail

Sha256Standalone

public Sha256Standalone()

Trivial 0-arguments constructor.

Method Detail

clone

public Object clone()

Description copied from interface: IMessageDigestStandalone

Returns a clone copy of this instance.

Specified by:

clone in interface IMessageDigestStandalone

Specified by:

clone in class BaseHashStandalone

Returns:

a clone copy of this instance.

transform

protected void transform(byte[] in,
                         int offset)

Description copied from class: BaseHashStandalone

The block digest transformation per se.

Specified by:

transform in class BaseHashStandalone

Parameters:

in - the blockSize long block, as an array of bytes to digest.

offset - the index where the data to digest is located within the input buffer.

padBuffer

protected byte[] padBuffer()

Description copied from class: BaseHashStandalone

Returns the byte array to use as padding before completing a hash operation.

Specified by:

padBuffer in class BaseHashStandalone

Returns:

the bytes to pad the remaining bytes in the buffer before completing a hash operation.

getResult

protected byte[] getResult()

Description copied from class: BaseHashStandalone

Constructs the result from the contents of the current context.

Specified by:

getResult in class BaseHashStandalone

Returns:

the output of the completed hash operation.

resetContext

protected void resetContext()

Description copied from class: BaseHashStandalone

Resets the instance for future re-use.

Specified by:

resetContext in class BaseHashStandalone

selfTest

public boolean selfTest()

Description copied from interface: IMessageDigestStandalone

A basic test. Ensures that the digest of a pre-determined message is equal to a known pre-computed value.

Specified by:

selfTest in interface IMessageDigestStandalone

Specified by:

selfTest in class BaseHashStandalone

Returns:

true if the implementation passes a basic self-test. Returns false otherwise.