org.bouncycastle.crypto.modes

Class G3413CFBBlockCipher

java.lang.Object

org.bouncycastle.crypto.DefaultMultiBlockCipher

org.bouncycastle.crypto.StreamBlockCipher

org.bouncycastle.crypto.modes.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 Summary

Constructors

Constructor and Description
G3413CFBBlockCipher(BlockCipher cipher) Base constructor.
G3413CFBBlockCipher(BlockCipher cipher, int bitBlockSize) Base constructor with specific block size.

Method Summary

Modifier and Type	Method and Description
protected byte	calculateByte(byte in)
java.lang.String	getAlgorithmName() Return the name of the algorithm the cipher implements.
int	getBlockSize() Return the block size for this cipher (in bytes).
void	init(boolean forEncryption, CipherParameters params) Initialise the cipher and initialisation vector R.
int	processBlock(byte[] in, int inOff, byte[] out, int outOff) Process one block of input from the array in and write it to the out array.
void	reset() copy R_init into R and reset the underlying cipher.

Methods inherited from class org.bouncycastle.crypto.StreamBlockCipher

getUnderlyingCipher, processBytes, returnByte

Methods inherited from class org.bouncycastle.crypto.DefaultMultiBlockCipher

getMultiBlockSize, processBlocks

Methods inherited from class java.lang.Object

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

Constructor Detail

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 Detail

init

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

java.lang.IllegalArgumentException

getAlgorithmName

public java.lang.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,
                        java.lang.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.

java.lang.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.