Re: [PATCH v43 01/15] Linux Random Number Generator

[Jeffrey Walton]

On Tue, Nov 30, 2021 at 9:04 AM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Tue, Nov 30, 2021 at 07:24:15AM -0500, Jeffrey Walton wrote:
> > On Mon, Nov 29, 2021 at 6:07 PM Greg Kroah-Hartman
> > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> > > ...
> > > Sometimes, yes, it is valid to have different implementations for things
> > > that do different things in the same area (like filesystems), but for a
> > > core function of the kernel, so far the existing random maintainer has
> > > not wanted to have multiple implementations.  Same goes for other parts
> > > of the kernel, it's not specific only to this one very tiny driver.
> > >
> > > As a counterpoint, we do not allow duplicate drivers that control the
> > > same hardware types in the tree.  We have tried that in the past and it
> > > was a nightmare to support and maintain and just caused massive user
> > > confusion as well.  One can argue that the random driver is in this same
> > > category.
> >
> > I think an argument could be made that they are different drivers
> > since they have different requirements and security goals. I don't
> > think it matters where the requirements came from, whether it was ad
> > hoc from the developer, NIST, KISA, CRYPTREC, NESSIE, or another
> > organization.
> >
> > Maybe the problem is with the name of the driver? Perhaps the current
> > driver should be named random-linux, Stephan's driver should be named
> > random-nist, and the driver should be wired up based on a user's
> > selection. That should sidestep the problems associated with the
> > "duplicate drivers" policy.
>
> The "problem" here is that the drivers/char/random.c file has three users,
> the userspace /dev/random and syscall api, the in-kernel "here's some
> entropy for the random core to use" api, and the in-kernel "give me some
> random data" api.
>
> Odds are, you REALLY do not want the in-kernel calls to be pulling from
> the "random-government-crippled-specification" implementation, right?

It's not a question of whether some folks want it or not. They have to
accept it due to policy. They have no choice in the matter.

I hope I don't sound argumentative. It's not my intention. But I know
what it's like to have to comply with policies, even ones I don't
like.

Jeff