Yes, the Chinese wall policy hook is there for checking whether the HVM
guest is allowed to run or not.
But the my question is that suppose the HVM guest wants to do some IO (disk
access, printer etc). Then for the communication with the
VMM, VMExit will happen ( A transition from the HVM guest to VMM is done). Then,
Where the shype/ACM put hooks in order to have control over
devices) for the HVM guests?
it puts hooks on hypercalls in case of paravirtualization.
shype/ACM does in case of full virtualization?
From: Stefan Berger
Sent: Tuesday, April 03, 2007 8:29
Subject: RE: [Xense-devel]
Shype/ACM for HVM guest.
<praveen.kushwaha@xxxxxxxxxxx> wrote on 04/03/2007 05:42:56 AM:
Yes that is fine if the
paravirtualized drivers are
> used in HVM then we can put hooks on that.
But it is different case,
> how actually shype/ACM works in case of
Since in case of VMExit/VMEntry there
> hypercalls, then how sHype/ACM implements
I mean to ask that how sHype/ACM
works in case of HVM guest.
In case of
an HVM guest you would have the Chinese Wall Policy hooks checking whether the
HVM guest is allowed to run with its current VM label.
resources such as image files is also checked when a virtual machine is started
> Praveen Kushwaha
> From: Stefan Berger
> Sent: Monday, April 02, 2007 7:19 PM
> To: Praveen
> Cc: xense-devel@xxxxxxxxxxxxxxxxxxx;
> Subject: Re: [Xense-devel] Shype/ACM for HVM
> xense-devel-bounces@xxxxxxxxxxxxxxxxxxx wrote
on 04/02/2007 05:40:39 AM:
> > Hi,
Does Shype/ACM architecture for implementing security in
> > xen supports HVM guest also? I
mean to say that, as per my
> HVM guests are supported in so far that the
configuration of an HVM
> is checked when the VM is started. This is
done in xend where
> resource assignments (disk access) are
> > knowledge in xen 3.0.4
shype/ACM is implemented. Does this
> > shype/ACM work also for the HVM
As per my understanding shype/ACM puts hook on
> > hypercalls from the hypervisor, and
consult with the ACM. But in
> > case of full virtualization, hypervisor
does not have hypercalls to
> > communicate with HVM guest. There is
> This is correct. Though, if paravirtualized
drivers are used in an
> HVM, also they will need to go through the
hooks for grant table
> access and event channels.
> > communication, in which guest state and
host state are saved. Since
> > there are no hypercalls in case of
full virtualization then how the
> > actually shype/ACM works. Where does it
put hooks? Or is there any
> > other mechanism through which it
implements security in HVM guest.
> > If any one has
information regarding it please reply.
> > Thanks,
> > Praveen
> > Xense-devel mailing list
> > Xense-devel@xxxxxxxxxxxxxxxxxxx
> > http://lists.xensource.com/xense-devel