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The FIPS 140-2 Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms certified to FIPS 140-2 level 1. This jar contains the debug version JCE provider and low-level API for the BC-FJA version 1.0.2.3, FIPS Certificate #3514. Please note the debug jar is not certified.

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package org.bouncycastle.crypto.fips;

import org.bouncycastle.crypto.EntropySource;
import org.bouncycastle.crypto.EntropySourceProvider;

class FixedEntropySourceProvider
    implements EntropySourceProvider
{
    private final byte[] data;
    private final boolean isPredictionResistant;

    protected FixedEntropySourceProvider(byte[] data, boolean isPredictionResistant)
    {
        this.data = data;
        this.isPredictionResistant = isPredictionResistant;
    }

    public EntropySource get(final int bitsRequired)
    {
        return new EntropySource()
        {
            int index = 0;

            public boolean isPredictionResistant()
            {
                return isPredictionResistant;
            }

            public byte[] getEntropy()
            {
                byte[] rv = new byte[(bitsRequired + 7) / 8];

                System.arraycopy(data, index, rv, 0, rv.length);

                index += (bitsRequired + 7) / 8;

                return rv;
            }

            public int entropySize()
            {
                return bitsRequired;
            }
        };
    }
}