iaik.security.random
Class AnsiRandom

java.lang.Object
  |
  +--java.util.Random
        |
        +--java.security.SecureRandom
              |
              +--iaik.security.random.SecRandom
                    |
                    +--iaik.security.random.AnsiRandom

All Implemented Interfaces:

Serializable

public class AnsiRandom

extends SecRandom

This class implements a secure pseudorandom generator as specified in ANSI X9.17. It was specified for the generation of DES initialization vectors, and consequently uses a seed of only 64 bits. Therefore, it cannot be recommended for general use. Because Triple DES is used to generate the output, the IAIK provider must be installed.

In addition to the seed, X9.17 defines that it shall use the current system time. That means, if you generate two instances of AnsiRandom, they will output a different pseudo random sequence even if you specified the same seed. A setI() method is defined to allow modification of that second seed value.

Version:

File Revision 16

See Also:

Serialized Form

Constructor Summary

AnsiRandom()
Generate a new AnsiRandom with the specified seed.

Method Summary

protected void	engineNextBytes(byte[] bytes) Return the next bytes.length pseudo random bytes.
protected void	engineSetSeed(byte[] seed) Set the seed to the given byte array.
void	setI() Set the I vector to the current time.
void	setI(long time) Set the I vector to the specified long.

Methods inherited from class iaik.security.random.SecRandom

getDefault, nextBytes, setDefault, setSeed, setSeed, setSeed

Methods inherited from class java.security.SecureRandom

generateSeed, getInstance, getInstance, getProvider, getSeed, next

Methods inherited from class java.util.Random

nextBoolean, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

AnsiRandom

public AnsiRandom()
           throws RandomException

Generate a new AnsiRandom with the specified seed. The seed must be at least eight bytes long, other bytes are ignored. The IAIK provider must be installed with Triple DES, otherwise a RandomException will be thrown.

Method Detail

setI

public void setI()

Set the I vector to the current time.

setI

public void setI(long time)

Set the I vector to the specified long. The I vector is a second seed value used in number generation.

engineNextBytes

protected void engineNextBytes(byte[] bytes)

Return the next bytes.length pseudo random bytes.

Overrides:

engineNextBytes in class SecRandom

engineSetSeed

protected void engineSetSeed(byte[] seed)

Set the seed to the given byte array. It must be at least eight bytes long, further bytes are ignored.

Overrides:

engineSetSeed in class SecRandom