iaik.security.md
Class SHA32bit

java.lang.Object
  |
  +--java.security.MessageDigestSpi
        |
        +--java.security.MessageDigest
              |
              +--iaik.security.md.AbstractMessageDigest
                    |
                    +--iaik.security.md.SHA32bit
All Implemented Interfaces:
Cloneable
Direct Known Subclasses:
SHA224, SHA256

public abstract class SHA32bit
extends iaik.security.md.AbstractMessageDigest

This class serves as the base class for the 32-bit hash algorithms SHA-256 and SHA-224 from NIST.

Version:
File Revision 4
See Also:
MessageDigest, SHA256

Method Summary
 Object clone()
          Returns a clone of this SHA256 Object.
protected  byte[] engineDigest()
          b>SPI: Completes the hash computation by performing final operations such as padding.
 int engineGetDigestLength()
          SPI: Returns the length of the digest in bytes.
 void engineReset()
          SPI: Resets this SHA256 message digest object for being supplied with new data.
protected  void engineUpdate(byte input)
          SPI: Updates the data to be hashed with the specified byte.
protected  void engineUpdate(byte[] input, int offset, int len)
          SPI: Updates the data to be hashed with the specified number of bytes, beginning at the specified offset within the given byte array.
 
Methods inherited from class java.security.MessageDigest
digest, digest, digest, getAlgorithm, getDigestLength, getInstance, getInstance, getProvider, isEqual, reset, toString, update, update, update
 
Methods inherited from class java.security.MessageDigestSpi
engineDigest
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Method Detail

clone

public Object clone()
Returns a clone of this SHA256 Object.
Overrides:
clone in class iaik.security.md.AbstractMessageDigest
Returns:
a clone of this SHA256 Object

engineReset

public void engineReset()
SPI: Resets this SHA256 message digest object for being supplied with new data.

This method is called by engineDigest after the actual hash computation has been finished to automatically reset the message digest object for being supplied with new data for starting a new hash computation.

Overrides:
engineReset in class iaik.security.md.AbstractMessageDigest
See Also:
AbstractMessageDigest.engineDigest()

engineUpdate

protected final void engineUpdate(byte input)
SPI: Updates the data to be hashed with the specified byte.
Overrides:
engineUpdate in class MessageDigestSpi
Parameters:
input - the byte to be used for updating.

engineUpdate

protected final void engineUpdate(byte[] input,
                                  int offset,
                                  int len)
SPI: Updates the data to be hashed with the specified number of bytes, beginning at the specified offset within the given byte array.
Overrides:
engineUpdate in class MessageDigestSpi
Parameters:
input - the byte array holding the data to be used for this update operation.
offset - the offset, indicating the start position within the given byte array.
len - the number of bytes to be obtained from the given byte array, starting at the given position.

engineDigest

protected byte[] engineDigest()
b>SPI: Completes the hash computation by performing final operations such as padding. Once engineDigest has been called, the engine should be reset. Resetting is the responsibility of the engine implementor.
Overrides:
engineDigest in class MessageDigestSpi
Returns:
The computed hash value.
See Also:
AbstractMessageDigest.engineReset()

engineGetDigestLength

public int engineGetDigestLength()
SPI: Returns the length of the digest in bytes.

May not be available for applications before JDK versions >= 1.2.x.

Overrides:
engineGetDigestLength in class MessageDigestSpi
Returns:
the length of the digest in bytes.

This Javadoc may contain text parts from Internet Standard specifications (RFC 2459, 3280, 3039, 2560, 1521, 821, 822, 2253, 1319, 1321, ,2630, 2631, 2268, 3058, 2984, 2104, 2144, 2040, 2311, 2279, see copyright note) and RSA Data Security Public-Key Cryptography Standards (PKCS#1,3,5,7,8,9,10,12, see copyright note).

IAIK-JCE 3.1 with IAIK-JCE CC Core 3.1, (c) 1997-2004 IAIK