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Date: Wed, 18 Oct 2017 20:18:48 +0100
From: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Message-ID: <20171018191847.GF3225@work-vm>
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Subject: Re: [Qemu-devel] libvirt/QEMU/SEV interaction
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To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>, "libvir-list@redhat.com" <libvir-list@redhat.com>, "Relph, Richard" <Richard.Relph@amd.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>, "Lendacky, Thomas" <Thomas.Lendacky@amd.com>

* Michael S. Tsirkin (mst@redhat.com) wrote:
> On Fri, Sep 08, 2017 at 10:48:10AM -0500, Brijesh Singh wrote:
> > > >      > 11. GO verifies the measurement and if measurement matches then it may
> > > >      >  give a secret blob -- which must be injected into the guest before
> > > >      >  libvirt starts the VM. If verification failed, GO will request cloud
> > > >      >  provider to destroy the VM.
> 
> I realised I'm missing something here: how does GO limit the
> secret to the specific VM? For example, what prevents hypervisor
> from launching two VMs with the same GO's DH, getting measurement
> from 1st one but injecting the secret into the second one?

Isn't that the 'trusted channel nonce currently associated with the
guest' in the guest context?

Dave

> Thanks,
> 
> -- 
> MST
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK