From: "Theo de Raadt" <deraadt@openbsd.org>
Subject: Re: Update from maintainer: devel/objfw 1.5.1
To: Jonathan Schleifer <js@nil.im>
Cc: ports@openbsd.org
Date: Wed, 04 Mar 2026 19:40:16 -0700

Jonathan Schleifer <js@nil.im> wrote:

> Am 04.03.26 um 05:41 schrieb Theo de Raadt:
> > The only way to do what you are talking about here is to dumb it
> > down to
> > the least capable subsystem.  But that will make it much, much, much
> > less ineffective than a pristine solution.  At that point the word
> > 'sandboxing becomes approximately as valuable as it has been for for a
> > while.  The bar should be high, but it is low.  But the word sandboxing is
> > always satisfied by performing the minimum.  "Oh we sandboxed it".  The
> > problem is the community understanding that a minimum sandbox is still
> > considered a sandbox.
> 
> The idea is not to provide a "sandbox" just to be able to check a
> checkmark, but to provide an actual security boundary.

  [ ] do you have something some random person would call a sandbox?

An unjusfified redential. I see.

> By abstraction, I don't mean a race to the bottom for the lowest
> common denominator (which is no sandboxing at all), but rather an
> abstraction over pledge+unveil that can also be made to work with
> Landlock (and maybe Capsicum). So it would deny everything by default
> and also allow no file system paths by default, except for those
> explicitly allowed.

None of the systems do that in a compatible way.

> This way, the least common denominator doesn't mean allowing - it
> means denying. So, if, for example (and this is fictitious) Landlock
> has no way to allow what pledge("ps") does, you just won't be able to
> get a list of processes in your sandboxed process. Some OS-specific
> promises could also be added to make the user fully aware that this
> only works on that specific OS - and will fail on any other OS.

How many programs can use landlock?

There is your answer.  How do you generalize a system so restrictive
that noone can adopt it, with the others?

You don't.

> And yes, this means there are plenty of sandbox systems out there that
> will plainly not be supported because they don't have "deny everything
> by default", making them IMHO useless anyway.

If you ignore all the details, you'll call everything a sandbox.

If you require the most stringent rules so that everything breaks,
it is not deployable, and if you can't generally deploy it it is not
a sandbox.