iaik.security.random

Class SecRandom

java.lang.Object

java.util.Random

java.security.SecureRandom

iaik.security.random.SecRandom

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

AES128SP80090Random, AES192SP80090Random, AES256SP80090Random, AnsiRandom, FIPS186Random, HMacSHA1SP80090Random, HMacSHA224SP80090Random, HMacSHA256SP80090Random, HMacSHA384SP80090Random, HMacSHA512SP80090Random, MessageDigestRandom, SHA1SP80090Random, SHA224SP80090Random, SHA256SP80090Random, SHA384SP80090Random, SHA512SP80090Random

public abstract class SecRandom
extends java.security.SecureRandom

The SecRandom class is the base class of all IAIK implemented secure pseudo random number generators (PRNGs). For compatibility with the JDK it is a subclass of java.security.SecureRandom, which in turn extends java.util.Random. Programmers who themselves want to implement a secure PRNG should subclass this class for compatibility and because this class takes care of some of the peculiarities of the JDK SecureRandom.

Subclasses just need to implement the abstract engineNextBytes() and engineSetSeed() methods and a no-args constructor. Subclasses should not seed themselves in the constructor, they should wait for the application to call a setSeed() method explicitly with data from an appropriate random source. This class makes sure that engineNextBytes() is never called before a seed has been set, if necessary by calling setSeed() itself with data from the default SeedGenerator.

This class also serves as storage point for the system's default secure PRNG. Applications which want to use a secure PRNG should typically call SecRandom.getDefault() instead of instantiating one particular PRNG directly. This will allow the PRNG used throughout the application to be set by a simple SecRandom.setDefault() call. The initial default PRNG is iaik.security.random.SHA256FIPS186Random.

Version:

File Revision 32

See Also:

SecureRandom, MessageDigestRandom, SHA256FIPS186Random, SeedGenerator, Serialized Form

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	SecRandom() Default constructor for backwards compatibility.

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.String	getAlgorithm() Gets the name of the algorithm.
static java.security.SecureRandom	getDefault() Return a new instance of the default random number generator.
static void	setDefault(java.lang.Class clazz) Deprecated. use setDefault(String)
static void	setDefault(java.lang.String prng) Set the default random number generator.
void	setSeed() Set the seed to the next seed generated by the current default seed generator.

Methods inherited from class java.security.SecureRandom

generateSeed, getInstance, getInstance, getInstance, getProvider, getSeed, next, nextBytes, setSeed, setSeed

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

SecRandom

protected SecRandom()

Default constructor for backwards compatibility.

Method Detail

getDefault

public static final java.security.SecureRandom getDefault()

Return a new instance of the default random number generator. It will not be assigned a seed (see also nextBytes()). Calling getDefault() is the recommended way of obtaining a PRNG. The initial default PRNG is iaik.security.random.SHA256FIPS186Random.

setDefault

public static final void setDefault(java.lang.Class clazz)
                             throws RandomException

Deprecated. use setDefault(String)

Set the default random number generator. Instances of this PRNG will be returned by subsequent calls of getDefault(). The PRNG must have a no-args constructor accessible to this class.

Parameters:

clazz - The default random class. It must be java.security.SecureRandom or a subclass of it.

Throws:

java.lang.IllegalArgumentException - if there was an error with the SecureRandom

RandomException

setDefault

public static final void setDefault(java.lang.String prng)
                             throws java.security.NoSuchAlgorithmException

Set the default random number generator. Instances of this PRNG will be returned by subsequent calls of getDefault().

Parameters:

prng - The identifier of the default random.

Throws:

java.lang.IllegalArgumentException - if there was an error with the SecureRandom

java.security.NoSuchAlgorithmException

setSeed

public final void setSeed()

Set the seed to the next seed generated by the current default seed generator. That means, calling this method is equivalent to calling setSeed(SeedGenerator.getDefault().getSeed());.

getAlgorithm

public java.lang.String getAlgorithm()

Gets the name of the algorithm.

Overrides:

getAlgorithm in class java.security.SecureRandom

Returns:

the name of the algorithm