A comment on a Microsoft blog from 2005 mentions over 150 sources of entropy for the Windows CryptGenRandom function. The majority of sources come from low-level system information (precise stat counters), the process' environment block, high-precision CPU counters, exception information, process information, and more. I have two questions about this entropy collection:

  1. Are all these entropy sources still used on modern Windows, more than a decade later?

  2. Are these sources queried at each randomness request, or is an entropy pool used?

The only two sources I could find give no information for modern Windows (post-XP).

  • iirc, they use fortuna, which means a pool. CryptGenRandom has largely been outmoded by .NET's RNGCryptoServiceProvider, which uses HWRNG. – dandavis Apr 5 '18 at 22:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.