SkeinDigest (Bouncy Castle Library (LTS Edition) 2.73.5 Provider API)

java.lang.Object
- org.bouncycastle.crypto.digests.SkeinDigest

All Implemented Interfaces:

Digest, ExtendedDigest, Memoable
```
public class SkeinDigest
extends java.lang.Object
implements ExtendedDigest, Memoable
```
Implementation of the Skein parameterised hash function in 256, 512 and 1024 bit block sizes, based on the Threefish tweakable block cipher.
This is the 1.3 version of Skein defined in the Skein hash function submission to the NIST SHA-3 competition in October 2010.
Skein was designed by Niels Ferguson - Stefan Lucks - Bruce Schneier - Doug Whiting - Mihir Bellare - Tadayoshi Kohno - Jon Callas - Jesse Walker.

See Also:

SkeinEngine, SkeinParameters

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`SKEIN_1024` 1024 bit block size - Skein-1024
`static int`	`SKEIN_256` 256 bit block size - Skein-256
`static int`	`SKEIN_512` 512 bit block size - Skein-512

Constructor Summary

Constructors
Constructor and Description
`SkeinDigest(int stateSizeBits, int digestSizeBits)` Constructs a Skein digest with an internal state size and output size.
`SkeinDigest(int stateSizeBits, int digestSizeBits, CryptoServicePurpose purpose)`
`SkeinDigest(SkeinDigest digest)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`Memoable`	`copy()` Produce a copy of this object with its configuration and in its current state.
`int`	`doFinal(byte[] out, int outOff)` close the digest, producing the final digest value.
`java.lang.String`	`getAlgorithmName()` return the algorithm name
`int`	`getByteLength()` Return the size in bytes of the internal buffer the digest applies it's compression function to.
`int`	`getDigestSize()` return the size, in bytes, of the digest produced by this message digest.
`void`	`init(SkeinParameters params)` Optionally initialises the Skein digest with the provided parameters. See `SkeinParameters` for details on the parameterisation of the Skein hash function.
`void`	`reset()` reset the digest back to it's initial state.
`void`	`reset(Memoable other)` Restore a copied object state into this object.
`void`	`update(byte in)` update the message digest with a single byte.
`void`	`update(byte[] in, int inOff, int len)` update the message digest with a block of bytes.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - SKEIN_256
```
public static final int SKEIN_256
```
    256 bit block size - Skein-256
    
    See Also:
    
    Constant Field Values
  - SKEIN_512
```
public static final int SKEIN_512
```
    512 bit block size - Skein-512
    
    See Also:
    
    Constant Field Values
  - SKEIN_1024
```
public static final int SKEIN_1024
```
    1024 bit block size - Skein-1024
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - SkeinDigest
```
public SkeinDigest(int stateSizeBits,
                   int digestSizeBits)
```
    Constructs a Skein digest with an internal state size and output size.
    
    Parameters:
    
    stateSizeBits - the internal state size in bits - one of SKEIN_256, SKEIN_512 or SKEIN_1024.
    
    digestSizeBits - the output/digest size to produce in bits, which must be an integral number of bytes.
  - SkeinDigest
```
public SkeinDigest(int stateSizeBits,
                   int digestSizeBits,
                   CryptoServicePurpose purpose)
```
  - SkeinDigest
```
public SkeinDigest(SkeinDigest digest)
```
- Method Detail
  - reset
```
public void reset(Memoable other)
```
    Description copied from interface: Memoable
    
    Restore a copied object state into this object.
    Implementations of this method should try to avoid or minimise memory allocation to perform the reset.
    
    Specified by:
    
    reset in interface Memoable
    
    Parameters:
    
    other - an object originally copied from an object of the same type as this instance.
  - copy
```
public Memoable copy()
```
    Description copied from interface: Memoable
    
    Produce a copy of this object with its configuration and in its current state.
    The returned object may be used simply to store the state, or may be used as a similar object starting from the copied state.
    
    Specified by:
    
    copy in interface Memoable
  - getAlgorithmName
```
public java.lang.String getAlgorithmName()
```
    Description copied from interface: Digest
    
    return the algorithm name
    
    Specified by:
    
    getAlgorithmName in interface Digest
    
    Returns:
    
    the algorithm name
  - getDigestSize
```
public int getDigestSize()
```
    Description copied from interface: Digest
    
    return the size, in bytes, of the digest produced by this message digest.
    
    Specified by:
    
    getDigestSize in interface Digest
    
    Returns:
    
    the size, in bytes, of the digest produced by this message digest.
  - getByteLength
```
public int getByteLength()
```
    Description copied from interface: ExtendedDigest
    
    Return the size in bytes of the internal buffer the digest applies it's compression function to.
    
    Specified by:
    
    getByteLength in interface ExtendedDigest
    
    Returns:
    
    byte length of the digests internal buffer.
  - init
```
public void init(SkeinParameters params)
```
    Optionally initialises the Skein digest with the provided parameters.
    See SkeinParameters for details on the parameterisation of the Skein hash function.
    
    Parameters:
    
    params - the parameters to apply to this engine, or null to use no parameters.
  - reset
```
public void reset()
```
    Description copied from interface: Digest
    
    reset the digest back to it's initial state.
    
    Specified by:
    
    reset in interface Digest
  - update
```
public void update(byte in)
```
    Description copied from interface: Digest
    
    update the message digest with a single byte.
    
    Specified by:
    
    update in interface Digest
    
    Parameters:
    
    in - the input byte to be entered.
  - update
```
public void update(byte[] in,
                   int inOff,
                   int len)
```
    Description copied from interface: Digest
    
    update the message digest with a block of bytes.
    
    Specified by:
    
    update in interface Digest
    
    Parameters:
    
    in - the byte array containing the data.
    
    inOff - the offset into the byte array where the data starts.
    
    len - the length of the data.
  - doFinal
```
public int doFinal(byte[] out,
                   int outOff)
```
    Description copied from interface: Digest
    
    close the digest, producing the final digest value. The doFinal call leaves the digest reset.
    
    Specified by:
    
    doFinal in interface Digest
    
    Parameters:
    
    out - the array the digest is to be copied into.
    
    outOff - the offset into the out array the digest is to start at.

Class SkeinDigest

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

SKEIN_256

SKEIN_512

SKEIN_1024

Constructor Detail

SkeinDigest

SkeinDigest

SkeinDigest

Method Detail

reset

copy

getAlgorithmName

getDigestSize

getByteLength

init

reset

update

update

doFinal