java.lang.Object
- org.bouncycastle.crypto.engines.NaccacheSternEngine

All Implemented Interfaces:

AsymmetricBlockCipher
```
public class NaccacheSternEngine
extends java.lang.Object
implements AsymmetricBlockCipher
```
NaccacheStern Engine. For details on this cipher, please see https://www.gemplus.com/smart/rd/publications/pdf/NS98pkcs.pdf

Constructor Summary

Constructors
Constructor Description

NaccacheSternEngine()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`byte[]`	`addCryptedBlocks(byte[] block1, byte[] block2)`	Adds the contents of two encrypted blocks mod sigma
`byte[]`	`encrypt(java.math.BigInteger plain)`	Encrypts a BigInteger aka Plaintext with the public key.
`int`	`getInputBlockSize()`	Returns the input block size of this algorithm.
`int`	`getOutputBlockSize()`	Returns the output block size of this algorithm.
`void`	`init(boolean forEncryption, CipherParameters param)`	Initializes this algorithm.
`byte[]`	`processBlock(byte[] in, int inOff, int len)`	Process a single Block using the Naccache-Stern algorithm.
`byte[]`	`processData(byte[] data)`	Convenience Method for data exchange with the cipher.
`void`	`setDebug(boolean debug)`

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

- Constructor Detail
  - NaccacheSternEngine
```
public NaccacheSternEngine()
```
- Method Detail
  - init
```
public void init(boolean forEncryption,
                 CipherParameters param)
```
    Initializes this algorithm. Must be called before all other Functions.
    
    Specified by:
    
    init in interface AsymmetricBlockCipher
    
    Parameters:
    
    forEncryption - if true the cipher is initialised for encryption, if false for decryption.
    
    param - the key and other data required by the cipher.
    
    See Also:
    
    AsymmetricBlockCipher.init(boolean, org.bouncycastle.crypto.CipherParameters)
  - setDebug
```
public void setDebug(boolean debug)
```
  - getInputBlockSize
```
public int getInputBlockSize()
```
    Returns the input block size of this algorithm.
    
    Specified by:
    
    getInputBlockSize in interface AsymmetricBlockCipher
    
    Returns:
    
    maximum size for an input block.
    
    See Also:
    
    AsymmetricBlockCipher.getInputBlockSize()
  - getOutputBlockSize
```
public int getOutputBlockSize()
```
    Returns the output block size of this algorithm.
    
    Specified by:
    
    getOutputBlockSize in interface AsymmetricBlockCipher
    
    Returns:
    
    maximum size of the output block produced by the cipher.
    
    See Also:
    
    AsymmetricBlockCipher.getOutputBlockSize()
  - processBlock
```
public byte[] processBlock(byte[] in,
                           int inOff,
                           int len)
                    throws InvalidCipherTextException
```
    Process a single Block using the Naccache-Stern algorithm.
    
    Specified by:
    
    processBlock in interface AsymmetricBlockCipher
    
    Parameters:
    
    in - the input data
    
    inOff - offset into the in array where the data starts
    
    len - the length of the block to be processed.
    
    Returns:
    
    the resulting byte array of the encryption/decryption process.
    
    Throws:
    
    InvalidCipherTextException - data decrypts improperly.
    
    See Also:
    
    AsymmetricBlockCipher.processBlock(byte[], int, int)
  - encrypt
```
public byte[] encrypt(java.math.BigInteger plain)
```
    Encrypts a BigInteger aka Plaintext with the public key.
    
    Parameters:
    
    plain - The BigInteger to encrypt
    
    Returns:
    
    The byte[] representation of the encrypted BigInteger (i.e. crypted.toByteArray())
  - addCryptedBlocks
```
public byte[] addCryptedBlocks(byte[] block1,
                               byte[] block2)
                        throws InvalidCipherTextException
```
    Adds the contents of two encrypted blocks mod sigma
    
    Parameters:
    
    block1 - the first encrypted block
    
    block2 - the second encrypted block
    
    Returns:
    
    encrypt((block1 + block2) mod sigma)
    
    Throws:
    
    InvalidCipherTextException
  - processData
```
public byte[] processData(byte[] data)
                   throws InvalidCipherTextException
```
    Convenience Method for data exchange with the cipher. Determines blocksize and splits data to blocksize.
    
    Parameters:
    
    data - the data to be processed
    
    Returns:
    
    the data after it went through the NaccacheSternEngine.
    
    Throws:
    
    InvalidCipherTextException

Class NaccacheSternEngine

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

NaccacheSternEngine

Method Detail

init

setDebug

getInputBlockSize

getOutputBlockSize

processBlock

encrypt

addCryptedBlocks

processData