public class CFBBlockCipher extends java.lang.Object implements BlockCipher
| Modifier and Type | Field and Description |
|---|---|
private int |
blockSize |
private byte[] |
cfbOutV |
private byte[] |
cfbV |
private BlockCipher |
cipher |
private boolean |
encrypting |
private byte[] |
IV |
| Constructor and Description |
|---|
CFBBlockCipher(BlockCipher cipher,
int bitBlockSize)
Basic constructor.
|
| Modifier and Type | Method and Description |
|---|---|
int |
decryptBlock(byte[] in,
int inOff,
byte[] out,
int outOff)
Do the appropriate processing for CFB mode decryption.
|
int |
encryptBlock(byte[] in,
int inOff,
byte[] out,
int outOff)
Do the appropriate processing for CFB mode encryption.
|
java.lang.String |
getAlgorithmName()
return the algorithm name and mode.
|
int |
getBlockSize()
return the block size we are operating at.
|
BlockCipher |
getUnderlyingCipher()
return the underlying block cipher that we are wrapping.
|
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 chaining vector back to the IV and reset the underlying
cipher.
|
private byte[] IV
private byte[] cfbV
private byte[] cfbOutV
private int blockSize
private BlockCipher cipher
private boolean encrypting
public CFBBlockCipher(BlockCipher cipher, int bitBlockSize)
cipher - the block cipher to be used as the basis of the
feedback mode.bitBlockSize - the block size in bits (note: a multiple of 8)public BlockCipher getUnderlyingCipher()
public void init(boolean encrypting,
CipherParameters params)
throws java.lang.IllegalArgumentException
init in interface BlockCipherencrypting - if true the cipher is initialised for
encryption, if false for decryption.params - the key and other data required by the cipher.java.lang.IllegalArgumentException - if the params argument is
inappropriate.public java.lang.String getAlgorithmName()
getAlgorithmName in interface BlockCipherpublic int getBlockSize()
getBlockSize in interface BlockCipherpublic int processBlock(byte[] in,
int inOff,
byte[] out,
int outOff)
throws DataLengthException,
java.lang.IllegalStateException
processBlock in interface BlockCipherin - 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.DataLengthException - if there isn't enough data in in, or
space in out.java.lang.IllegalStateException - if the cipher isn't initialised.public int encryptBlock(byte[] in,
int inOff,
byte[] out,
int outOff)
throws DataLengthException,
java.lang.IllegalStateException
in - the array containing the data to be encrypted.inOff - offset into the in array the data starts at.out - the array the encrypted data will be copied into.outOff - the offset into the out array the output will start at.DataLengthException - if there isn't enough data in in, or
space in out.java.lang.IllegalStateException - if the cipher isn't initialised.public int decryptBlock(byte[] in,
int inOff,
byte[] out,
int outOff)
throws DataLengthException,
java.lang.IllegalStateException
in - the array containing the data to be decrypted.inOff - offset into the in array the data starts at.out - the array the encrypted data will be copied into.outOff - the offset into the out array the output will start at.DataLengthException - if there isn't enough data in in, or
space in out.java.lang.IllegalStateException - if the cipher isn't initialised.public void reset()
reset in interface BlockCipherCopyright © 1998-2014 Gamma Technologies. All Rights Reserved.