Class SICBlockCipher

All Implemented Interfaces:
BlockCipher, CTRModeCipher, MultiBlockCipher, SkippingCipher, SkippingStreamCipher, StreamCipher

public class SICBlockCipher extends StreamBlockCipher implements CTRModeCipher
Implements the Segmented Integer Counter (SIC) mode on top of a simple block cipher. This mode is also known as CTR mode.
  • Constructor Details

    • SICBlockCipher

      public SICBlockCipher(BlockCipher c)
      Deprecated.
      use newInstance() method.
      Basic constructor.
      Parameters:
      c - the block cipher to be used.
  • Method Details

    • newInstance

      public static CTRModeCipher newInstance(BlockCipher cipher)
      Return a new SIC/CTR mode cipher based on the passed in base cipher
      Parameters:
      cipher - the base cipher for the SIC/CTR mode.
    • init

      public void init(boolean forEncryption, CipherParameters params) throws IllegalArgumentException
      Description copied from interface: BlockCipher
      Initialise the cipher.
      Specified by:
      init in interface BlockCipher
      Specified by:
      init in interface StreamCipher
      Parameters:
      forEncryption - if true the cipher is initialised for encryption, if false for decryption.
      params - the key and other data required by the cipher.
      Throws:
      IllegalArgumentException - if the params argument is inappropriate.
    • getAlgorithmName

      public String getAlgorithmName()
      Description copied from interface: BlockCipher
      Return the name of the algorithm the cipher implements.
      Specified by:
      getAlgorithmName in interface BlockCipher
      Specified by:
      getAlgorithmName in interface StreamCipher
      Returns:
      the name of the algorithm the cipher implements.
    • getBlockSize

      public int getBlockSize()
      Description copied from interface: BlockCipher
      Return the block size for this cipher (in bytes).
      Specified by:
      getBlockSize in interface BlockCipher
      Returns:
      the block size for this cipher in bytes.
    • processBlock

      public int processBlock(byte[] in, int inOff, byte[] out, int outOff) throws DataLengthException, IllegalStateException
      Description copied from interface: BlockCipher
      Process one block of input from the array in and write it to the out array.
      Specified by:
      processBlock in interface BlockCipher
      Parameters:
      in - the array containing the input data.
      inOff - offset into the in array the data starts at.
      out - the array the output data will be copied into.
      outOff - the offset into the out array the output will start at.
      Returns:
      the number of bytes processed and produced.
      Throws:
      DataLengthException - if there isn't enough data in input , or space in out.
      IllegalStateException - if the cipher isn't initialised.
    • 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
      Overrides:
      processBytes in class StreamBlockCipher
      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.
    • calculateByte

      protected byte calculateByte(byte in) throws DataLengthException, IllegalStateException
      Specified by:
      calculateByte in class StreamBlockCipher
      Throws:
      DataLengthException
      IllegalStateException
    • reset

      public void reset()
      Description copied from interface: BlockCipher
      Reset the cipher. After resetting the cipher is in the same state as it was after the last init (if there was one).
      Specified by:
      reset in interface BlockCipher
      Specified by:
      reset in interface StreamCipher
    • skip

      public long skip(long numberOfBytes)
      Description copied from interface: SkippingCipher
      Skip numberOfBytes forwards, or backwards.
      Specified by:
      skip in interface SkippingCipher
      Parameters:
      numberOfBytes - the number of bytes to skip (positive forward, negative backwards).
      Returns:
      the number of bytes actually skipped.
    • seekTo

      public long seekTo(long position)
      Description copied from interface: SkippingCipher
      Reset the cipher and then skip forward to a given position.
      Specified by:
      seekTo in interface SkippingCipher
      Parameters:
      position - the number of bytes in to set the cipher state to.
      Returns:
      the byte position moved to.
    • getPosition

      public long getPosition()
      Description copied from interface: SkippingCipher
      Return the current "position" of the cipher
      Specified by:
      getPosition in interface SkippingCipher
      Returns:
      the current byte position.