public final class Twofish extends BaseCipher
Twofish is a balanced 128-bit Feistel cipher, consisting of 16 rounds. In each round, a 64-bit S-box value is computed from 64 bits of the block, and this value is xored into the other half of the block. The two half-blocks are then exchanged, and the next round begins. Before the first round, all input bits are xored with key-dependent "whitening" subkeys, and after the final round the output bits are xored with other key-dependent whitening subkeys; these subkeys are not used anywhere else in the algorithm.
Twofish is designed by Bruce Schneier, Doug Whiting, John Kelsey, Chris Hall, David Wagner and Niels Ferguson.
References:
currentBlockSize, currentKey, defaultBlockSize, defaultKeySize, lock, name
CIPHER_BLOCK_SIZE, KEY_MATERIAL
Constructor and Description |
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Twofish()
Trivial 0-arguments constructor.
|
Modifier and Type | Method and Description |
---|---|
java.util.Iterator |
blockSizes()
Returns an
Iterator over the supported block sizes. |
java.lang.Object |
clone()
Returns a clone of this instance.
|
void |
decrypt(byte[] in,
int inOffset,
byte[] out,
int outOffset,
java.lang.Object sessionKey,
int bs) |
void |
encrypt(byte[] in,
int inOffset,
byte[] out,
int outOffset,
java.lang.Object sessionKey,
int bs) |
java.util.Iterator |
keySizes()
Returns an
Iterator over the supported key sizes. |
java.lang.Object |
makeKey(byte[] k,
int bs)
Expands a user-supplied key material into a session key for a designated
block size.
|
boolean |
selfTest()
A correctness test that consists of basic symmetric encryption /
decryption test(s) for all supported block and key sizes, as well as one
(1) variable key Known Answer Test (KAT).
|
currentBlockSize, decryptBlock, defaultBlockSize, defaultKeySize, encryptBlock, init, name, reset, testKat, testKat
public java.lang.Object clone()
IBlockCipher
Returns a clone of this instance.
clone
in interface IBlockCipher
clone
in class BaseCipher
public java.util.Iterator blockSizes()
IBlockCipher
Returns an Iterator
over the supported block sizes. Each
element returned by this object is an Integer
.
Iterator
over the supported block sizes.public java.util.Iterator keySizes()
IBlockCipher
Returns an Iterator
over the supported key sizes. Each element
returned by this object is an Integer
.
Iterator
over the supported key sizes.public java.lang.Object makeKey(byte[] k, int bs) throws java.security.InvalidKeyException
Expands a user-supplied key material into a session key for a designated block size.
k
- the 64/128/192/256-bit user-key to use.bs
- the desired block size in bytes.java.lang.IllegalArgumentException
- if the block size is not 16 (128-bit).java.security.InvalidKeyException
- if the key data is invalid.public void encrypt(byte[] in, int inOffset, byte[] out, int outOffset, java.lang.Object sessionKey, int bs)
public void decrypt(byte[] in, int inOffset, byte[] out, int outOffset, java.lang.Object sessionKey, int bs)
public boolean selfTest()
IBlockCipher
A correctness test that consists of basic symmetric encryption / decryption test(s) for all supported block and key sizes, as well as one (1) variable key Known Answer Test (KAT).
selfTest
in interface IBlockCipher
selfTest
in class BaseCipher
true
if the implementation passes simple
correctness tests. Returns false
otherwise.Copyright © 2025. All rights reserved.