From: "Cristian Rodríguez" <crrodriguez@opensuse.org>
To: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Noah Goldstein <goldstein.w.n@gmail.com>,
Adhemerval Zanella <adhemerval.zanella@linaro.org>,
GNU C Library <libc-alpha@sourceware.org>,
Florian Weimer <fweimer@redhat.com>
Subject: Re: [PATCH v1 1/2] random-bits: Factor out entropy generating function
Date: Thu, 31 Mar 2022 07:08:08 -0300 [thread overview]
Message-ID: <CAPBLoAec_OCGDsC8-69L60=r-xRVvZEsMZmALj4HO6ZcpmC4=g@mail.gmail.com> (raw)
In-Reply-To: <CAHmME9q8XLzmPjYJV0yK6TK7BQbNEcoeEp0_9yW-+FxaUm+OcA@mail.gmail.com>
On Thu, Mar 31, 2022 at 1:45 AM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
> Can someone provide some context on this? I've actually looked into
> having some megafast userspace RNG component in the vDSO, and I'm not
> fundamentally opposed to the idea. I think there's interesting
> potential there and something worth considering. But what's the
> context of you asking for this now? Under what circumstances are you
> finding that calling getrandom(0) or similar is too high overhead or
> otherwise problematic?
I'm not sure in what scenario the syscall overhead is too big, Maybe
it is if called in a loop..but I guess the argument here is that
getrandom(0) may block or that in a non-bleeding edge system it might
be too slow. (Im aware of the recent massive speedups)
I believe what is needed is a PRNG, no need to guarantee to be
cryptographically secure, that can be used without having to seed it
from userspace, mega fast, never blocks and can be used by the dynamic
linker for example. Now it will be awesome if it is all of that and
CSPRNG.
next prev parent reply other threads:[~2022-03-31 10:08 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-28 22:09 Noah Goldstein
2022-03-28 22:09 ` [PATCH v1 2/2] x86: Use rdtsc for generating entropy for random_bits Noah Goldstein
2022-03-29 19:51 ` [PATCH v1 1/2] random-bits: Factor out entropy generating function Adhemerval Zanella
2022-03-29 19:56 ` Noah Goldstein
2022-03-29 20:04 ` Noah Goldstein
2022-03-29 20:14 ` H.J. Lu
2022-03-29 20:44 ` Adhemerval Zanella
2022-03-29 20:52 ` Noah Goldstein
2022-03-29 20:37 ` Adhemerval Zanella
2022-03-29 20:44 ` Noah Goldstein
2022-03-30 15:37 ` Adhemerval Zanella
2022-03-30 16:30 ` Noah Goldstein
2022-03-30 19:38 ` Cristian Rodríguez
2022-03-31 4:45 ` Jason A. Donenfeld
2022-03-31 10:08 ` Cristian Rodríguez [this message]
2022-03-31 11:17 ` Adhemerval Zanella
2022-03-31 11:25 ` Cristian Rodríguez
2022-03-31 11:48 ` Adhemerval Zanella
2022-03-31 12:14 ` Cristian Rodríguez
2022-03-31 13:12 ` Yann Droneaud
2022-03-31 15:31 ` Jason A. Donenfeld
2022-03-31 18:16 ` Noah Goldstein
2022-03-31 21:57 ` Cristian Rodríguez
2022-03-31 22:33 ` Noah Goldstein
2022-03-31 22:51 ` Jason A. Donenfeld
2022-03-31 23:05 ` Noah Goldstein
2022-03-31 23:25 ` Jason A. Donenfeld
2022-04-01 18:01 ` Cristian Rodríguez
2022-04-04 17:42 ` Adhemerval Zanella
2022-04-04 18:23 ` Noah Goldstein
2022-04-04 18:38 ` Adhemerval Zanella
2022-04-04 18:52 ` Noah Goldstein
2022-04-04 19:20 ` Adhemerval Zanella
2022-04-04 19:48 ` Noah Goldstein
2022-04-04 19:57 ` Adhemerval Zanella
2022-04-04 14:51 ` Florian Weimer
2022-04-04 14:54 ` Jason A. Donenfeld
2022-04-04 15:00 ` Florian Weimer
2022-04-04 16:51 ` Noah Goldstein
2022-04-04 17:22 ` Adhemerval Zanella
2022-04-04 18:32 ` Jason A. Donenfeld
2022-04-04 19:16 ` Noah Goldstein
2022-04-05 0:10 ` Cristian Rodríguez
2022-04-05 0:18 ` Jason A. Donenfeld
2022-04-05 13:45 ` Cristian Rodríguez
2022-04-05 9:22 ` Florian Weimer
2022-04-04 18:28 ` Jason A. Donenfeld
2022-04-05 9:20 ` Florian Weimer
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