RSABlindingEngine (Bouncy Castle Library 1.60 API Specification)

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

All Implemented Interfaces:

AsymmetricBlockCipher
```
public class RSABlindingEngine
extends java.lang.Object
implements AsymmetricBlockCipher
```
This does your basic RSA Chaum's blinding and unblinding as outlined in "Handbook of Applied Cryptography", page 475. You need to use this if you are trying to get another party to generate signatures without them being aware of the message they are signing.

Constructor Summary

Constructors
Constructor Description

RSABlindingEngine()

Constructors
Constructor	Description
`RSABlindingEngine()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`getInputBlockSize()`	Return the maximum size for an input block to this engine.
`int`	`getOutputBlockSize()`	Return the maximum size for an output block to this engine.
`void`	`init(boolean forEncryption, CipherParameters param)`	Initialise the blinding engine.
`byte[]`	`processBlock(byte[] in, int inOff, int inLen)`	Process a single block using the RSA blinding algorithm.

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

- Constructor Detail
  - RSABlindingEngine
```
public RSABlindingEngine()
```
- Method Detail
  - init
```
public void init(boolean forEncryption,
                 CipherParameters param)
```
    Initialise the blinding engine.
    
    Specified by:
    
    init in interface AsymmetricBlockCipher
    
    Parameters:
    
    forEncryption - true if we are encrypting (blinding), false otherwise.
    
    param - the necessary RSA key parameters.
  - getInputBlockSize
```
public int getInputBlockSize()
```
    Return the maximum size for an input block to this engine. For RSA this is always one byte less than the key size on encryption, and the same length as the key size on decryption.
    
    Specified by:
    
    getInputBlockSize in interface AsymmetricBlockCipher
    
    Returns:
    
    maximum size for an input block.
  - getOutputBlockSize
```
public int getOutputBlockSize()
```
    Return the maximum size for an output block to this engine. For RSA this is always one byte less than the key size on decryption, and the same length as the key size on encryption.
    
    Specified by:
    
    getOutputBlockSize in interface AsymmetricBlockCipher
    
    Returns:
    
    maximum size for an output block.
  - processBlock
```
public byte[] processBlock(byte[] in,
                           int inOff,
                           int inLen)
```
    Process a single block using the RSA blinding algorithm.
    
    Specified by:
    
    processBlock in interface AsymmetricBlockCipher
    
    Parameters:
    
    in - the input array.
    
    inOff - the offset into the input buffer where the data starts.
    
    inLen - the length of the data to be processed.
    
    Returns:
    
    the result of the RSA process.
    
    Throws:
    
    DataLengthException - the input block is too large.

Class RSABlindingEngine

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RSABlindingEngine

Method Detail

init

getInputBlockSize

getOutputBlockSize

processBlock