Re: [PATCH v24 00/12] /dev/random - a new approach with full SP800-90B compliance

From: Florian Weimer
Date: Tue Nov 12 2019 - 08:23:24 EST


* Stephan Müller:

> * support deactivation of TRNG (i.e. blocking behavior of /dev/random)
> at compile time. If deactivated, /dev/random behaves like
> getrandom(2).

I don't quite understand this comment. Doesn't getrandom with the
GRND_RANDOM always behave like /dev/random? Presumably, without the
TRNG tap, the GRND_RANDOM flag for getrandom is ignored, and reading
from /dev/random behaves like reading from /dev/urandom.

Anyway, reading the accompanying PDF, this looks rather impressive:
the userspace bootstrapping problem is gone (the issue where waiting
for more entropy prevents the collection of more entropy), *and* we
can still make the standards people happy.

(Replying from my other account due to mail issues, sorry.)