How to cite files on a CD-ROM?
I find the easiest way to cite scientific software is to search it on Google Scholar and see if anyone else has cited it. In this case, searching for "DIEHARD: a battery of tests of randomness" yields one result that's been cited in 614 papers. Clicking the cite button and picking BibTex gives the following: 

@article{marsaglia1997diehard,   
  title={The Diehard random number testsuite},
  author={Marsaglia, George},
  journal={http://stat.fsu.edu/pub/diehard},
  year={1997}
}


You may want to throw a \url{} around the address, but otherwise that should work for you. Just mention the specific test in your paper when you cite it.