[libvirt] [PATCH V1 4/6] Add SELinux labeling support for TPM

[Daniel P. Berrange]

On Thu, Mar 14, 2013 at 08:00:21PM -0400, Stefan Berger wrote:
> On 03/14/2013 06:34 PM, Daniel P. Berrange wrote:
> >On Thu, Mar 14, 2013 at 04:24:27PM -0400, Stefan Berger wrote:
> >>On 03/14/2013 10:29 AM, Daniel P. Berrange wrote:
> >>>On Wed, Mar 13, 2013 at 12:03:52PM -0400, Stefan Berger wrote:
> >>>>Signed-off-by: Stefan Berger <stefanb at linux.vnet.ibm.com>
> >>>>
> >>>>---
> >>>>  src/security/security_selinux.c |   90 ++++++++++++++++++++++++++++++++++++++++
> >>>>  1 file changed, 90 insertions(+)
> >>>I imagine we also need to update security_apparmour.c and
> >>>security_dac.c.
> >>DAC: this seems to only be necessary if the the owner of the device
> >>is not root. Typically it is owned by root. I added support for it
> >>anyway now.
> >>AppArmour: it looks like no other character devices are being
> >>labeled so I may not have to do this for the TPM, either (?)
> >>
> >>
> >>>Also src/conf/domain_audit.c will need to emit an audit event when the
> >>>TPM is configured to use a host device.
> >>type=VIRT_RESOURCE msg=audit(1363292411.635:499): pid=23365 uid=0
> >>auid=4294967295 ses=4294967295
> >>subj=system_u:system_r:virtd_t:s0-s0:c0.c1023 msg='virt=kvm
> >>resrc=cgroup reason=allow vm="TPM-PT"
> >>uuid=a4d7cd22-da89-3094-6212-079a48a309a1
> >>cgroup="/sys/fs/cgroup/devices/libvirt/qemu/TPM-PT/" class=path
> >>path=/dev/tpm0 rdev=0A:E0 acl=rw exe="/usr/sbin/libvirtd" hostname=?
> >>addr=? terminal=? res=success'
> >>
> >>Is this message type sufficient for a host device?
> >No, this is just a generic message related to cgroups setup.
> >We need to emit explicit audit log for each device in addition
> >to this, since we cannot assume cgroups is enabled.
> >
> >We need to extend the virDomainAuditStart method to include
> >this new device type.
> 
> Ok, so now libvirt is also printing this one here:
> 
> type=VIRT_RESOURCE msg=audit(1363305463.181:1302): pid=17807 uid=0
> auid=0 ses=1
> subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023
> msg='virt=kvm resrc=dev reason=start vm="TPM-PT"
> uuid=a4d7cd22-da89-3094-6212-079a48a309a1 device="/dev/tpm0"
> exe="/usr/sbin/libvirtd" hostname=? addr=? terminal=pts/20
> res=success'
> 
> I suppose the msg='' part is somewhat device specific. So above
> really only shows /dev/tpm0 and I don't think there's much else
> worth mentioning.

Yep, that's fine - people using these are just interested in the name
of the device / file on the host being used by the VM.


> The last thing is now in which patch to put this :-) I would keep it
> in a separate patch after the one touching the SELinux and DAC
> labeling...

Sure, separate patch is fine.

Daniel
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