http://www.bouncycastle.org/java.html: The Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms. This jar contains JCE provider and lightweight API for the Bouncy Castle Cryptography APIs for JDK 1.5 to JDK 1.8.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.crypto.prng.drbg;


Interface to SP800-90A deterministic random bit generators.

/**
 * Interface to SP800-90A deterministic random bit generators.
 */
public interface SP80090DRBG
{
    
Return the block size of the DRBG.

Returns:the block size (in bits) produced by each round of the DRBG.
/**
     * Return the block size of the DRBG.
     *
     * @return the block size (in bits) produced by each round of the DRBG.
     */
    int getBlockSize();

    
Populate a passed in array with random data.

Params:
  • output – output array for generated bits.
  • additionalInput – additional input to be added to the DRBG in this step.
  • predictionResistant – true if a reseed should be forced, false otherwise.
Returns:number of bits generated, -1 if a reseed required.
/**
     * Populate a passed in array with random data.
     *
     * @param output output array for generated bits.
     * @param additionalInput additional input to be added to the DRBG in this step.
     * @param predictionResistant true if a reseed should be forced, false otherwise.
     *
     * @return number of bits generated, -1 if a reseed required.
     */
    int generate(byte[] output, byte[] additionalInput, boolean predictionResistant);

    
Reseed the DRBG.

Params:
  • additionalInput – additional input to be added to the DRBG in this step.
/**
     * Reseed the DRBG.
     *
     * @param additionalInput additional input to be added to the DRBG in this step.
     */
    void reseed(byte[] additionalInput);
}