org.bouncycastle.crypto.macs
Class CFBBlockCipherMac
java.lang.Object
org.bouncycastle.crypto.macs.CFBBlockCipherMac
- Mac
public class CFBBlockCipherMac
extends java.lang.Object
CFBBlockCipherMac
public CFBBlockCipherMac(BlockCipher cipher)
create a standard MAC based on a CFB block cipher. This will produce an
authentication code half the length of the block size of the cipher, with
the CFB mode set to 8 bits.
cipher
- the cipher to be used as the basis of the MAC generation.
CFBBlockCipherMac
public CFBBlockCipherMac(BlockCipher cipher,
int cfbBitSize,
int macSizeInBits)
create a standard MAC based on a block cipher with the size of the
MAC been given in bits. This class uses CFB mode as the basis for the
MAC generation.
Note: the size of the MAC must be at least 24 bits (FIPS Publication 81),
or 16 bits if being used as a data authenticator (FIPS Publication 113),
and in general should be less than the size of the block cipher as it reduces
the chance of an exhaustive attack (see Handbook of Applied Cryptography).
cipher
- the cipher to be used as the basis of the MAC generation.cfbBitSize
- the size of an output block produced by the CFB mode.macSizeInBits
- the size of the MAC in bits, must be a multiple of 8.
CFBBlockCipherMac
public CFBBlockCipherMac(BlockCipher cipher,
int cfbBitSize,
int macSizeInBits,
BlockCipherPadding padding)
create a standard MAC based on a block cipher with the size of the
MAC been given in bits. This class uses CFB mode as the basis for the
MAC generation.
Note: the size of the MAC must be at least 24 bits (FIPS Publication 81),
or 16 bits if being used as a data authenticator (FIPS Publication 113),
and in general should be less than the size of the block cipher as it reduces
the chance of an exhaustive attack (see Handbook of Applied Cryptography).
cipher
- the cipher to be used as the basis of the MAC generation.cfbBitSize
- the size of an output block produced by the CFB mode.macSizeInBits
- the size of the MAC in bits, must be a multiple of 8.padding
- a padding to be used.
CFBBlockCipherMac
public CFBBlockCipherMac(BlockCipher cipher,
BlockCipherPadding padding)
create a standard MAC based on a CFB block cipher. This will produce an
authentication code half the length of the block size of the cipher, with
the CFB mode set to 8 bits.
cipher
- the cipher to be used as the basis of the MAC generation.padding
- the padding to be used.
doFinal
public int doFinal(byte[] out,
int outOff)
- doFinal in interface Mac
reset
public void reset()
Reset the mac generator.
- reset in interface Mac
update
public void update(byte in)
- update in interface Mac
update
public void update(byte[] in,
int inOff,
int len)
- update in interface Mac