Package org.bouncycastle.crypto.engines

## Class HC128Engine

- java.lang.Object
- - org.bouncycastle.crypto.engines.HC128Engine

- All Implemented Interfaces:
    `StreamCipher`

      public class HC128Engine
      extends java.lang.Object
      implements StreamCipher

  HC-128 is a software-efficient stream cipher created by Hongjun Wu. It generates keystream from a 128-bit secret key and a 128-bit initialization vector.

  https://www.ecrypt.eu.org/stream/p3ciphers/hc/hc128_p3.pdf

  It is a third phase candidate in the eStream contest, and is patent-free. No attacks are known as of today (April 2007). See https://www.ecrypt.eu.org/stream/hcp3.html

- - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `HC128Engine()` |

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `java.lang.String` | `getAlgorithmName()` | Return the name of the algorithm the cipher implements.
    `void` | `init​(boolean forEncryption, CipherParameters params)` | Initialise a HC-128 cipher.
    `int` | `processBytes​(byte[] in, int inOff, int len, byte[] out, int outOff)` | process a block of bytes from in putting the result into out.
    `void` | `reset()` | reset the cipher.
    `byte` | `returnByte​(byte in)` | encrypt/decrypt a single byte returning the result.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Constructor Detail

    - #### HC128Engine

          public HC128Engine()

  - ### Method Detail

    - #### getAlgorithmName

          public java.lang.String getAlgorithmName()

      Description copied from interface: `StreamCipher`
      Return the name of the algorithm the cipher implements.
      Specified by:
        `getAlgorithmName` in interface `StreamCipher`
      Returns:
        the name of the algorithm the cipher implements.

    - #### init

          public void init​(boolean forEncryption,
                           CipherParameters params)
                    throws java.lang.IllegalArgumentException

      Initialise a HC-128 cipher.
      Specified by:
        `init` in interface `StreamCipher`
      Parameters:
        `forEncryption` - whether or not we are for encryption. Irrelevant, as encryption and decryption are the same.
        `params` - the parameters required to set up the cipher.
      Throws:
        `java.lang.IllegalArgumentException` - if the params argument is inappropriate (ie. the key is not 128 bit long).

    - #### processBytes

          public int processBytes​(byte[] in,
                                  int inOff,
                                  int len,
                                  byte[] out,
                                  int outOff)
                           throws DataLengthException

      Description copied from interface: `StreamCipher`
      process a block of bytes from in putting the result into out.
      Specified by:
        `processBytes` in interface `StreamCipher`
      Parameters:
        `in` - the input byte array.
        `inOff` - the offset into the in array where the data to be processed starts.
        `len` - the number of bytes to be processed.
        `out` - the output buffer the processed bytes go into.
        `outOff` - the offset into the output byte array the processed data starts at.
      Returns:
        the number of bytes produced - should always be len.
      Throws:
        `DataLengthException` - if the output buffer is too small.

    - #### reset

          public void reset()

      Description copied from interface: `StreamCipher`
      reset the cipher. This leaves it in the same state it was at after the last init (if there was one).
      Specified by:
        `reset` in interface `StreamCipher`

    - #### returnByte

          public byte returnByte​(byte in)

      Description copied from interface: `StreamCipher`
      encrypt/decrypt a single byte returning the result.
      Specified by:
        `returnByte` in interface `StreamCipher`
      Parameters:
        `in` - the byte to be processed.
      Returns:
        the result of processing the input byte.