On Tue, 2022-05-17 at 19:27 +0200, Jason A. Donenfeld wrote:
> On Fri, May 13, 2022 at 04:57:00PM +0200, Ahmad Fatoum wrote:
> > + trusted.rng= [KEYS]
> > + Format: <string>
> > + The RNG used to generate key material for trusted keys.
> > + Can be one of:
> > + - "kernel"
> > + - the same value as trusted.source: "tpm" or "tee"
> > + - "default"
> > + If not specified, "default" is used. In this case,
> > + the RNG's choice is left to each individual trust source.
> > +
>
> As a general mechanism, I object to this. The kernel's RNG must be
> trusted in the first place for key material. That's the whole point of
> it.
I would relax this a bit: kernel's RNG must be implicitly must be
trusted. If the parameter is used, you make an explicit choice that
you are aware of the trust.
If this was opt-out parameter, instead of opt-in, I would get your
argument.
> However, it sounds like you're not proposing a general mechanism, but
> just something particular to this "trusted keys" business. In that case,
> this should be a module flag, and thus not documented here, but rather
> some place namespaced to your trusted keys stuff. "trusted_keys.preferred_rng={whatever}"
However, I think this a good proposal. Let's make it a module parameter
instead.
> Jason
BR, Jarkko
