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The FIPS 140-3 Bouncy Castle Crypto package is a Java implementation of cryptographic algorithms certified to FIPS 140-3 level 1. This jar contains JCE provider and low-level API for the BC-FJA version 2.0.0, FIPS Certificate #4743. Please see certificate for certified platform details.

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package org.bouncycastle.crypto.general;

import org.bouncycastle.crypto.internal.KeyGenerationParameters;
import org.bouncycastle.crypto.internal.params.DesParameters;

class DesKeyGenerator
    extends CipherKeyGenerator
{
    /**
     * initialise the key generator - if strength is set to zero
     * the key generated will be 64 bits in size, otherwise
     * strength can be 64 or 56 bits (if you don't count the parity bits).
     *
     * @param param the parameters to be used for key generation
     */
    public void init(
        KeyGenerationParameters param)
    {
        super.init(param);

        if (strength == 0 || strength == (56 / 8))
        {
            strength = DesParameters.DES_KEY_LENGTH;
        }
        else if (strength != DesParameters.DES_KEY_LENGTH)
        {
            throw new IllegalArgumentException("DES key must be "
                    + (DesParameters.DES_KEY_LENGTH * 8)
                    + " bits long.");
        }
    }

    public byte[] generateKey()
    {
        byte[]  newKey = new byte[DesParameters.DES_KEY_LENGTH];

        do
        {
            random.nextBytes(newKey);

            DesParameters.setOddParity(newKey);
        }
        while (DesParameters.isWeakKey(newKey, 0));

        return newKey;
    }
}