Class G3413CTRBlockCipher

All Implemented Interfaces:
BlockCipher, MultiBlockCipher, StreamCipher

public class G3413CTRBlockCipher extends StreamBlockCipher
implements the GOST 3412 2015 CTR counter mode (GCTR).
  • Constructor Details

    • G3413CTRBlockCipher

      public G3413CTRBlockCipher(BlockCipher cipher)
      Basic constructor.
      Parameters:
      cipher - the block cipher to be used as the basis of the counter mode (must have a 64 bit block size).
    • G3413CTRBlockCipher

      public G3413CTRBlockCipher(BlockCipher cipher, int bitBlockSize)
      Basic constructor.
      Parameters:
      cipher - the block cipher to be used as the basis of the counter mode (must have a 64 bit block size).
      bitBlockSize - basic unit (defined as s)
  • Method Details

    • init

      public void init(boolean encrypting, CipherParameters params) throws IllegalArgumentException
      Initialise the cipher and, possibly, the initialisation vector (IV). If an IV isn't passed as part of the parameter, the IV will be all zeros. An IV which is too short is handled in FIPS compliant fashion.
      Parameters:
      encrypting - 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()
      return the algorithm name and mode.
      Returns:
      the name of the underlying algorithm followed by "/GCTR" and the block size in bits
    • getBlockSize

      public int getBlockSize()
      return the block size we are operating at (in bytes).
      Returns:
      the block size we are operating at (in bytes).
    • processBlock

      public int processBlock(byte[] in, int inOff, byte[] out, int outOff) throws DataLengthException, IllegalStateException
      Process one block of input from the array in and write it to the out array.
      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 in, or space in out.
      IllegalStateException - if the cipher isn't initialised.
    • calculateByte

      protected byte calculateByte(byte in)
      Specified by:
      calculateByte in class StreamBlockCipher
    • reset

      public void reset()
      reset the feedback vector back to the IV and reset the underlying cipher.