Package org.bouncycastle.crypto.modes
Class GOFBBlockCipher
- java.lang.Object
-
- org.bouncycastle.crypto.StreamBlockCipher
-
- org.bouncycastle.crypto.modes.GOFBBlockCipher
-
- All Implemented Interfaces:
BlockCipher
,StreamCipher
public class GOFBBlockCipher extends StreamBlockCipher
implements the GOST 28147 OFB counter mode (GCTR).
-
-
Constructor Summary
Constructors Constructor Description GOFBBlockCipher(BlockCipher cipher)
Basic constructor.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description protected byte
calculateByte(byte b)
java.lang.String
getAlgorithmName()
return the algorithm name and mode.int
getBlockSize()
return the block size we are operating at (in bytes).void
init(boolean encrypting, CipherParameters params)
Initialise the cipher and, possibly, the initialisation vector (IV).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()
reset the feedback vector back to the IV and reset the underlying cipher.-
Methods inherited from class org.bouncycastle.crypto.StreamBlockCipher
getUnderlyingCipher, processBytes, returnByte
-
-
-
-
Constructor Detail
-
GOFBBlockCipher
public GOFBBlockCipher(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).
-
-
Method Detail
-
init
public void init(boolean encrypting, CipherParameters params) throws java.lang.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:
java.lang.IllegalArgumentException
- if the params argument is inappropriate.
-
getAlgorithmName
public java.lang.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, java.lang.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.java.lang.IllegalStateException
- if the cipher isn't initialised.
-
reset
public void reset()
reset the feedback vector back to the IV and reset the underlying cipher.
-
calculateByte
protected byte calculateByte(byte b)
- Specified by:
calculateByte
in classStreamBlockCipher
-
-