gnu.javax.crypto.cipher
Class Twofish
- Cloneable, IBlockCipher, gnu.javax.crypto.cipher.IBlockCipherSpi
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:
- Twofish: A
128-bit Block Cipher.
Twofish()- Trivial 0-arguments constructor.
|
Iterator<E> | blockSizes()- Returns an
Iterator over the supported block sizes.
|
Object | clone()- Returns a clone of this instance.
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void | decrypt(byte[] in, int inOffset, byte[] out, int outOffset, Object sessionKey, int bs)- Decrypts exactly one block of ciphertext.
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void | encrypt(byte[] in, int inOffset, byte[] out, int outOffset, Object sessionKey, int bs)- Encrypts exactly one block of plaintext.
|
Iterator<E> | keySizes()- Returns an
Iterator over the supported key sizes.
|
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).
|
clone, currentBlockSize, decryptBlock, defaultBlockSize, defaultKeySize, encryptBlock, init, name, reset, selfTest, testKat, testKat |
clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait |
Twofish
public Twofish()
Trivial 0-arguments constructor.
decrypt
public void decrypt(byte[] in,
int inOffset,
byte[] out,
int outOffset,
Object sessionKey,
int bs) Decrypts exactly one block of ciphertext.
- decrypt in interface gnu.javax.crypto.cipher.IBlockCipherSpi
in - the ciphertext.inOffset - index of in from which to start considering
data.out - the plaintext.outOffset - index of out from which to store the
result.bs - the block size to use.
encrypt
public void encrypt(byte[] in,
int inOffset,
byte[] out,
int outOffset,
Object sessionKey,
int bs) Encrypts exactly one block of plaintext.
- encrypt in interface gnu.javax.crypto.cipher.IBlockCipherSpi
in - the plaintext.inOffset - index of in from which to start considering
data.out - the ciphertext.outOffset - index of out from which to store the
result.bs - the block size to use.
makeKey
public Object makeKey(byte[] k,
int bs)
throws InvalidKeyException Expands a user-supplied key material into a session key for a designated
block size.
- makeKey in interface gnu.javax.crypto.cipher.IBlockCipherSpi
k - the 64/128/192/256-bit user-key to use.bs - the desired block size in bytes.
- an Object encapsulating the session key.
selfTest
public 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).
- selfTest in interface IBlockCipher
- selfTest in interface gnu.javax.crypto.cipher.IBlockCipherSpi
- selfTest in interface BaseCipher
true if the implementation passes simple
correctness tests. Returns false otherwise.
Twofish.java --
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