Class G3413CFBBlockCipher

All Implemented Interfaces:
BlockCipher, MultiBlockCipher, StreamCipher

public class G3413CFBBlockCipher extends StreamBlockCipher
An implementation of the CFB mode for GOST 3412 2015 cipher. See GOST R 3413 2015
  • Constructor Details

    • G3413CFBBlockCipher

      public G3413CFBBlockCipher(BlockCipher cipher)
      Base constructor.
      Parameters:
      cipher - base cipher
    • G3413CFBBlockCipher

      public G3413CFBBlockCipher(BlockCipher cipher, int bitBlockSize)
      Base constructor with specific block size.
      Parameters:
      cipher - base cipher
      bitBlockSize - basic unit (defined as s)
  • Method Details

    • init

      public void init(boolean forEncryption, CipherParameters params) throws IllegalArgumentException
      Initialise the cipher and initialisation vector R. 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. R_init = IV, and R1 = R_init
      Parameters:
      forEncryption - ignored because encryption and decryption are same
      params - the key and other data required by the cipher.
      Throws:
      IllegalArgumentException
    • getAlgorithmName

      public String getAlgorithmName()
      Description copied from interface: StreamCipher
      Return the name of the algorithm the cipher implements.
      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).
      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.
      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.
    • calculateByte

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

      public void reset()
      copy R_init into R and reset the underlying cipher.