Re: [PATCH 0/8] MODSIGN: Use PKCS#7 for module signatures [ver #4]

From: "Luis R. Rodriguez" <mcgrof@suse.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: David Howells <dhowells@redhat.com>,
	Andy Lutomirski <luto@kernel.org>,
	Rusty Russell <rusty@rustcorp.com.au>,
	Michal Marek <mmarek@suse.cz>,
	Matthew Garrett <mjg59@srcf.ucam.org>,
	keyrings@linux-nfs.org,
	Dmitry Kasatkin <dmitry.kasatkin@gmail.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	Seth Forshee <seth.forshee@canonical.com>,
	LSM List <linux-security-module@vger.kernel.org>,
	David Woodhouse <dwmw2@infradead.org>
Subject: Re: [PATCH 0/8] MODSIGN: Use PKCS#7 for module signatures [ver #4]
Date: Thu, 21 May 2015 14:59:27 -0700	[thread overview]
Message-ID: <CAB=NE6UurGCp6QF992nTPW-QPQcpF9_O7LDxKsWToFTeWApy_w@mail.gmail.com> (raw)
In-Reply-To: <CALCETrUvf==bxwx80PT=F4bmZ4-BZVA47H_oh2t9mhgM4z8wmg@mail.gmail.com>

On Thu, May 21, 2015 at 2:44 PM, Andy Lutomirski <luto@amacapital.net> wrote:
>
> One option would be to add another type of verifiable thing.  We can
> verify modules, and we should add firmware to the types of things that
> can be signed.  We could add signing keys, too.  IOW, you could ask
> the kernel to load a signing key with certain rights, and, if they key
> is validly signed by some other key that has the same rights and has a
> bit set saying that it can delegate those rights, then the kernel will
> add that signing key to the keyring.
>
> If the general infrastructure were there, this would be very little
> additional code.

I really like this idea, but I've heard of many great ideas before
followed by nothing but vaporware. So is it a direct requirement to
implicate blocking a change for current module signature checking
strategy to a new one given the concerns you raise, or can we enable
those who wish to want additional better solutions as the one you
propose to opt-in to develop those solutions? I like the idea of the
later given that it seems those using the current module signing
infrastructure would prefer the change and enabling what you say does
not seem to be a not possible based on allowing that to be advanced.

 Luis