From mboxrd@z Thu Jan  1 00:00:00 1970
From: ludo@gnu.org (Ludovic =?UTF-8?Q?Court=C3=A8s?=)
Subject: bug#23605: /dev/urandom not seeded across reboots
Date: Wed, 25 May 2016 23:53:33 +0200
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	(David Thompson's message of "Tue, 24 May 2016 12:26:29 -0400")
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To: "Thompson, David" <dthompson2@worcester.edu>
Cc: 23605@debbugs.gnu.org

"Thompson, David" <dthompson2@worcester.edu> skribis:

> On Tue, May 24, 2016 at 12:16 PM, Leo Famulari <leo@famulari.name> wrote:

[...]

>> When I boot a GuixSD VM for the first time [0], it requires me to dance
>> on the keyboard until it has collected ~200 bits of entropy. I assumed
>> this is to properly bootstrap the CSPRNG in /dev/urandom, but I'm not
>> sure.
>
> This is just an annoying feature of GNU lsh.  I want to switch my
> machines to OpenSSH sometime, partly due to this.

It=E2=80=99s actually =E2=80=98lsh-make-seed=E2=80=99 that does that (info =
"(lsh)
lsh-make-seed"), and it=E2=80=99s invoked from our =E2=80=98lsh-service=E2=
=80=99 when
#:initialize? is #t (the default).

It=E2=80=99s possible to set #:initialize? to #f, but then you still need to
create (or provide) the random seed at some point.  At the time people
felt that having it default to #t would be less surprising.

> It impedes automated provisioning of servers, which OpenSSH does not do.

Maybe OpenSSH assumes that the kernel-provided randomness is good
enough?

Ludo=E2=80=99.