In the DESKey constructors, we're parity adjusting the data passed in, I believe
we should be copying it out, then adjusting it.

        this.key = new byte[DESKeySpec.DES_KEY_LEN];
        DESKeyGenerator.setParityBit(key, offset);
        System.arraycopy(key, offset, this.key, 0, DESKeySpec.DES_KEY_LEN);