The qemu_domain.c file is big as is and we should split it into
separate semantic blocks. Start with code that handles domain
namespaces.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like in the previous commit, the stdin_path argument of
virSecurityManagerSetAllLabel() is renamed to incomingPath.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The only consumer was removed in the previous commit.
This reverts commit f03a38bd1d.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Currently, when restoring from a domain the path that the domain
restores from is labelled under qemuSecuritySetAllLabel() (and after
v6.3.0-rc1~108 even outside transactions). While this grants QEMU
the access, it has a flaw, because once the domain is restored, up
and running then qemuSecurityDomainRestorePathLabel() is called,
which is not real counterpart. In case of DAC driver the
SetAllLabel() does nothing with the restore path but
RestorePathLabel() does - it chown()-s the file back and since there
is no original label remembered, the file is chown()-ed to
root:root. While the apparent solution is to have DAC driver set the
label (and thus remember the original one) in SetAllLabel(), we can
do better.
Turns out, we are opening the file ourselves (because it may live on
a root squashed NFS) and then are just passing the FD to QEMU. But
this means, that we don't have to chown() the file at all, we need
to set SELinux labels and/or add the path to AppArmor profile.
And since we want to restore labels right after QEMU is done loading
the migration stream (we don't want to wait until
qemuSecurityRestoreAllLabel()), the best way to approach this is to
have separate APIs for labelling and restoring label on the restore
file.
I will investigate whether AppArmor can use the SavedStateLabel()
API instead of passing the restore path to SetAllLabel().
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1851016
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Correct the log name for qemu_security.c to qemu.qemu_security
instead of qemu.qemu_process.
Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
In a few cases we might set seclabels on a path outside of
namespaces. For instance, when restoring a domain from a file,
the file is opened, relabelled and only then the namespace is
created and the FD is passed to QEMU (see v6.3.0-rc1~108 for more
info). Therefore, when restoring the label on the restore file,
we must ignore domain namespaces and restore the label directly
in the host.
This bug demonstrates itself when restoring a domain from a block
device. We don't create the block device inside the domain
namespace and thus the following error is reported at the end of
(otherwise successful) restore:
error : virProcessRunInFork:1236 : internal error: child reported (status=125): unable to stat: /dev/sda: No such file or directory
error : virProcessRunInFork:1240 : unable to stat: /dev/sda: No such file or directory
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The function calls virSecurityManagerDomainRestorePathLabel()
after all.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
The new name is virSecurityManagerDomainRestorePathLabel().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
After previous commit this function is used no more.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
As explained in the previous commit, we need to relabel the file
we are restoring the domain from. That is the FD that is passed
to QEMU. If the file is not under /dev then the file inside the
namespace is the very same as the one in the host. And regardless
of using transactions, the file will be relabeled. But, if the
file is under /dev then when using transactions only the copy
inside the namespace is relabeled and the one in the host is not.
But QEMU is reading from the one in the host, actually.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1772838
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
When preparing images for block jobs we modify their seclabels so
that QEMU can open them. However, as mentioned in the previous
commit, secdrivers base some it their decisions whether the image
they are working on is top of of the backing chain. Fortunately,
in places where we call secdrivers we know this and the
information can be passed to secdrivers.
The problem is the following: after the first blockcommit from
the base to one of the parents the XATTRs on the base image are
not cleared and therefore the second attempt to do another
blockcommit fails. This is caused by blockcommit code calling
qemuSecuritySetImageLabel() over the base image, possibly
multiple times (to ensure RW/RO access). A naive fix would be to
call the restore function. But this is not possible, because that
would deny QEMU the access to the base image. Fortunately, we
can use the fact that seclabels are remembered only for the top
of the backing chain and not for the rest of the backing chain.
And thanks to the previous commit we can tell secdrivers which
images are top of the backing chain.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1803551
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
In upcoming commits, virSecurityManagerSetAllLabel() will perform
rollback in case of failure by calling
virSecurityManagerRestoreAllLabel(). But in order to do that, the
former needs to have @migrated argument so that it can be passed
to the latter.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
See function documentation. Used in a following patch.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Add a generic way to run a command through the security management.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Set the transactionStarted to false if the commit failed. If this is not
done, then the failure path will report 'no transaction is set' and hide
more useful error reports.
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20190726210706.24440-2-stefanb@linux.ibm.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The same can be achieved by using qemuSecurity[Set|Restore]ImageLabel.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The flag will control the VIR_SECURITY_DOMAIN_IMAGE_LABEL_BACKING_CHAIN
flag of the security driver image labeling APIs.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Security labeling of disks consists of labeling of the disk image
itself and it's backing chain. Modify
virSecurityManager[Set|Restore]ImageLabel to take a boolean flag that
will label the full chain rather than the top image itself.
This allows to delete/unify some parts of the code and will also
simplify callers in some cases.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.
In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.
With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to find the
author of a particular bit of code.
This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.
The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When metadata locking is enabled that means the security commit
processing will be run in a fork similar to how namespaces use fork()'s
for processing. This is done to ensure libvirt can properly and
synchronously modify the metadata to store the original owner data.
Since fork()'s (e.g. virFork) have been seen as a performance bottleneck
being able to disable them allows the admin to choose whether the
performance 'hit' is worth the extra 'security' of being able to
remember the original owner of a lock.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The TPM code currently accepts pointer to a domain definition.
This is okay for now, but in near future the security driver APIs
it calls will require domain object. Therefore, change the TPM
code to accept the domain object pointer.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Now that committing transactions using pid == -1 means that we're
not fork()-ing to run the transaction in a specific namespace, we
can utilize the transaction processing semantics in order to
start, run a or multiple commands, and then commit the
transaction without being concerned with other interactions or
transactions interrupting the processing. This will eventually
allow us to have a single place where all the paths can be
locked, followed by relabeling and unlocking again.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Even though the current use of the functions does not require full
implementation with transactions (none of the callers passes a path
somewhere under /dev), it doesn't hurt either. Moreover, in
future patches the paradigm is going to shift so that any API
that touches a file is required to use transactions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Even though the current use of the function does not require full
implementation with transactions (none of the callers pass a path
somewhere under /dev), it doesn't hurt either. Moreover, in
future patches the paradigm is going to shift so that any API
that touches a file is required to use transactions.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In this patch we label the swtpm process with SELinux labels. We give it the
same label as the QEMU process has. We label its state directory and files
as well. We restore the old security labels once the swtpm has terminated.
The file and process labels now look as follows:
Directory: /var/lib/libvirt/swtpm
[root@localhost swtpm]# ls -lZ
total 4
rwx------. 2 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 4096 Apr 5 16:46 testvm
[root@localhost testvm]# ls -lZ
total 8
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 3648 Apr 5 16:46 tpm-00.permall
The log in /var/log/swtpm/libvirt/qemu is labeled as follows:
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 2237 Apr 5 16:46 vtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep swtpm | grep ctrl | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 tss 25664 0.0 0.0 28172 3892 ? Ss 16:57 0:00 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/testvm-swtpm.sock,mode=0660 --tpmstate dir=/var/lib/libvirt/swtpm/testvm/tpm1.2 --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep qemu | grep tpm | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 qemu 25669 99.0 0.0 3096704 48500 ? Sl 16:57 3:28 /bin/qemu-system-x86_64 [..]
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In the case that virtlogd is used as stdio handler we pass to QEMU
only FD to a PIPE connected to virtlogd instead of the file itself.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1430988
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Now that we have APIs for relabel memdevs on hotplug, fill in the
missing implementation in qemu hotplug code.
The qemuSecurity wrappers might look like overkill for now,
because qemu namespace code does not deal with the nvdimms yet.
Nor does our cgroup code. But hey, there's cgroup_device_acl
variable in qemu.conf. If users add their /dev/pmem* device in
there, the device is allowed in cgroups and created in the
namespace so they can successfully passthrough it to the domain.
It doesn't look like overkill after all, does it?
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Just like we need wrappers over other virSecurityManager APIs, we
need one for virSecurityManagerSetImageLabel and
virSecurityManagerRestoreImageLabel. Otherwise we might end up
relabelling device in wrong namespace.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The idea is to move all the seclabel setting to security driver.
Having the relabel code spread all over the place looks very
messy.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Because of the nature of security driver transactions, it is
impossible to use them properly. The thing is, transactions enter
the domain namespace and commit all the seclabel changes.
However, in RestoreAllLabel() this is impossible - the qemu
process, the only process running in the namespace, is gone. And
thus is the namespace. Therefore we shouldn't use the transactions
as there is no namespace to enter.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
So far if qemu is spawned under separate mount namespace in order
to relabel everything it needs an access to the security driver
to run in that namespace too. This has a very nasty down side -
it is being run in a separate process, so any internal state
transition is NOT reflected in the daemon. This can lead to many
sleepless nights. Therefore, use the transaction APIs so that
libvirt developers can sleep tight again.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Instead of trying to fix our security drivers, we can use a
simple trick to relabel paths in both namespace and the host.
I mean, if we enter the namespace some paths are still shared
with the host so any change done to them is visible from the host
too.
Therefore, we can just enter the namespace and call
SetAllLabel()/RestoreAllLabel() from there. Yes, it has slight
overhead because we have to fork in order to enter the namespace.
But on the other hand, no complexity is added to our code.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
