Post #2553655

2025-11-11 15:22 UTC

Random numbers should be hard to predict, and they carry no inherent meaning. Once you have a source of high-quality random numbers and a good PRNG making them fast, there isn't really anything else that can be added on top. And if we allow things to be added on top, that increases the risk that information about the bytes could leak before they reach their intended destination.

Replies (2)

@sunfish@hachyderm.io 2025-11-11 16:18

To be sure, the above is oversimplifying the situation somewhat. For example, perhaps someone doesn't trust the quality of the buitin random data, and wants to mix it with data from another source. But then, what other source would that be, in practice, and is that actually how we want secure applications to work? There are more questions here.

Open ##2553656
@yosh@toot.yosh.is 2025-11-11 15:37

@sunfish@hachyderm.io For secure RNG you're entirely right - but for insecure RNG being able to virtualize number generation can actually be really useful to guarantee determinism. This isn't just useful for testing, but also for use cases like hermetic build systems which want to be fully deterministic. I can definitely see cases where an impl might want to virtualize that.

Open ##2553657