Re: Should we automatically generate a module signing key at all?

[David Woodhouse <dwmw2@infradead.org>]

On Tue, 2015-05-19 at 13:05 -0700, Andy Lutomirski wrote:
> > I appreciate why that's a problem in your scenario, but it's a valid and
> > useful feature of signatures, and I don't think we can just abandon it.
> 
> True, but I'd consider that use case (running a kernel built on a
> development machine) to be more in line with unsigned use or long-term
> (maybe medium-term) signing keys.
> 
> IOW, for this use case, running scripts/generate_module_signing_key or
> whatever and configuring accordingly seems entirely reasonable to me.
> Or you could just turn off forced module signature verification since
> keeping the signing key in plaintext on your machine mostly negates
> any benefit of verifying signatures on that machine at runtime.

Perhaps so (although it's ignoring use cases where the build tree is
somewhere secure and internal and I'm deploying to a server which is
more accessible).

But we already *fixed* the problem of generating the signing key
automatically. The in-tree signing_key.{priv,x509} are always transient
auto-generated files now, and the ambiguity is gone. As a side-effect of
what I was already doing to enable PKCS#11. It was mostly just a
documentation change.

So I'm not sure I see the point of ditching it, now that it's working.

-- 
David Woodhouse                            Open Source Technology Centre
David.Woodhouse@intel.com                              Intel Corporation