3 ms·

Quite a long read, but I think it explains the situation quite well: https://www.2uo.de/myths-about-urandom/ https://www.2uo.de/myths-about-urandom/

• snakeanus 9y ago
  Also an interesting and related article https://sockpuppet.org/blog/2014/02/25/safely-generate-random-numbers/ https://sockpuppet.org/blog/2014/02/25/safely-generate-rando...
• Tomte 9y ago
  Unfortunately, the article isn't in the best shape right now. Back when it was written, things were clear: random and urandom are the same. Then came getrandom as a distraction. Now urandom is based on chacha. So it's different (but not worse – still, harder to explain). The article's structure couldn't easily accomodate those changes, and time was and is in short supply, and so it's not wrong, but much less forceful and clear than it used to be. I hope it shapes up soon, but don't promise anything! Still, I don't know a more up-to-date article. Maybe Thomas Pornin has something newer on StackOverflow?
  • snakeanus 9y ago
    > Now urandom is based on chacha Did Linux follow the example set by OpenBSD?
    • Tomte 9y ago
      I think so, yes. getrandom(2) is also an OpenBSD thing (getentropy), but of course they had to rename it and add a few options...