SICSeekableBlockCipher (TrueZIP Driver ZIP.RAES (TZP) 7.2-rc-2 API)

java.lang.Object
- de.schlichtherle.truezip.crypto.SICSeekableBlockCipher

All Implemented Interfaces:

SeekableBlockCipher, BlockCipher
```
public class SICSeekableBlockCipher
extends java.lang.Object
implements SeekableBlockCipher
```
Implements Counter (CTR) mode (alias Segmented Integer Counter - SIC). on top of a simple block cipher. This code is based on bouncy castle's SICBlockCipher class, but also allows random access to a block.

Author:

The Legion of the Bouncy Castle (majority of the code), Christian Schlichtherle (optimizations and extension to support seeking)

Field Summary

Fields
Modifier and Type	Field and Description
`private long`	`blockCounter`
`private int`	`blockSize`
`private BlockCipher`	`cipher`
`private byte[]`	`counterIn`
`private byte[]`	`counterOut`
`private byte[]`	`IV`

Constructor Summary

Constructors
Constructor and Description

SICSeekableBlockCipher(BlockCipher cipher)
Basic constructor.

Constructors
Constructor and Description
`SICSeekableBlockCipher(BlockCipher cipher)` Basic constructor.

Method Summary

Methods
Modifier and Type	Method and Description
`java.lang.String`	`getAlgorithmName()`
`long`	`getBlockCounter()` Returns the index of the block, starting at 0, which will be processed next when `BlockCipher.processBlock(byte[], int, byte[], int)` is called.
`int`	`getBlockSize()`
`BlockCipher`	`getUnderlyingCipher()` Returns the underlying block cipher which we are decorating.
`void`	`init(boolean forEncryption, CipherParameters params)`
`int`	`processBlock(byte[] in, int inOff, byte[] out, int outOff)`
`void`	`reset()`
`void`	`setBlockCounter(long block)` Sets the counter so that the block with the given index, starting at 0, can be processed next.
`private void`	`updateCounter()`

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

- Field Detail
  - cipher
```
private final BlockCipher cipher
```
  - blockSize
```
private final int blockSize
```
  - IV
```
private final byte[] IV
```
  - counterIn
```
private final byte[] counterIn
```
  - blockCounter
```
private long blockCounter
```
  - counterOut
```
private final byte[] counterOut
```
- Constructor Detail
  - SICSeekableBlockCipher
```
public SICSeekableBlockCipher(BlockCipher cipher)
```
    Basic constructor.
    
    Parameters:
    cipher - The block cipher to be used.
- Method Detail
  - getUnderlyingCipher
```
public BlockCipher getUnderlyingCipher()
```
    Returns the underlying block cipher which we are decorating.
    
    Returns:
    The underlying block cipher which we are decorating.
  - init
```
public void init(boolean forEncryption,
        CipherParameters params)
          throws java.lang.IllegalArgumentException
```
    Specified by:
    
    init in interface BlockCipher
    
    Throws:
    
    java.lang.IllegalArgumentException
  - getAlgorithmName
```
public java.lang.String getAlgorithmName()
```
    Specified by:
    
    getAlgorithmName in interface BlockCipher
  - getBlockSize
```
public int getBlockSize()
```
    Specified by:
    
    getBlockSize in interface BlockCipher
  - processBlock
```
public int processBlock(byte[] in,
               int inOff,
               byte[] out,
               int outOff)
                 throws DataLengthException,
                        java.lang.IllegalStateException
```
    Specified by:
    
    processBlock in interface BlockCipher
    
    Throws:
    
    DataLengthException
    
    java.lang.IllegalStateException
  - updateCounter
```
private void updateCounter()
```
  - setBlockCounter
```
public void setBlockCounter(long block)
```
    Description copied from interface: SeekableBlockCipher
    
    Sets the counter so that the block with the given index, starting at 0, can be processed next.
    
    Specified by:
    
    setBlockCounter in interface SeekableBlockCipher
    
    Parameters:
    block - The index of the block, starting at 0, which will be processed next when BlockCipher.processBlock(byte[], int, byte[], int) is called.
  - getBlockCounter
```
public long getBlockCounter()
```
    Description copied from interface: SeekableBlockCipher
    
    Returns the index of the block, starting at 0, which will be processed next when BlockCipher.processBlock(byte[], int, byte[], int) is called.
    
    Specified by:
    
    getBlockCounter in interface SeekableBlockCipher
  - reset
```
public void reset()
```
    Specified by:
    
    reset in interface BlockCipher

Class SICSeekableBlockCipher

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

cipher

blockSize

IV

counterIn

blockCounter

counterOut

Constructor Detail

SICSeekableBlockCipher

Method Detail

getUnderlyingCipher

init

getAlgorithmName

getBlockSize

processBlock

updateCounter

setBlockCounter

getBlockCounter

reset