Currently the driver module loading code does not report an error if the
driver module is physically missing on disk. This is useful for distro
packaging optional pieces. When the daemons are split up into one daemon
per driver, we will expect module loading to always succeed. If a driver
is not desired, the entire daemon should not be installed.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

So far we are repeating the following lines over and over:

  if (!(virSomeObjectClass = virClassNew(virClassForObject(),
                             "virSomeObject",
                             sizeof(virSomeObject),
                             virSomeObjectDispose)))
      return -1;

While this works, it is impossible to do some checking. Firstly,
the class name (the 2nd argument) doesn't match the name in the
code in all cases (the 3rd argument). Secondly, the current style
is needlessly verbose. This commit turns example into following:

  if (!(VIR_CLASS_NEW(virSomeObject,
                      virClassForObject)))
      return -1;
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

nvdimm memory is backed by a path on the host. This currently works only via
hotplug where the AppArmor label is created via the domain label callbacks.

This adds the virt-aa-helper support for nvdimm memory devices to generate
rules for the needed paths from the initial guest definition as well.

Example in domain xml:
  <memory model='nvdimm'>
    <source>
      <path>/tmp/nvdimm-base</path>
    </source>
    <target>
     <size unit='KiB'>524288</size>
     <node>0</node>
    </target>
  </memory>
Works to start now and creates:
  "/tmp/nvdimm-base" rw,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1757085Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Input devices can passthrough an event device. This currently works only via
hotplug where the AppArmor label is created via the domain label callbacks.

This adds the virt-aa-helper support for passthrough input devices to generate
rules for the needed paths from the initial guest definition as well.

Example in domain xml:
  <input type='passthrough' bus='virtio'>
          <source evdev='/dev/input/event0' />
  </input>
Works to start now and creates:
  "/dev/input/event0" rw,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1757085Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

d8116b5a "security: Introduce functions for input device hot(un)plug"
implemented the code (Set|Restore)InputLabel for several security modules,
this patch adds an AppArmor implementation for it as well.

That fixes hot-plugging event input devices by generating a rule for the
path that needs to be accessed.

Example hot adding:
  <input type='passthrough' bus='virtio'>
     <source evdev='/dev/input/event0' />
  </input>
Creates now:
  "/dev/input/event0" rwk,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1755153Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Recent changes have made implementing this mandatory to hot add any
memory.
Implementing this in apparmor fixes this as well as allows hot-add of nvdimm
tpye memory with an nvdimmPath set generating a AppArmor rule for that
path.

Example hot adding:
  <memory model='nvdimm'>
    <source>
      <path>/tmp/nvdimm-test</path>
    </source>
    <target>
      <size unit='KiB'>524288</size>
      <node>0</node>
    </target>
  </memory>
Creates now:
  "/tmp/nvdimm-test" rwk,

Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1755153Acked-by: NJamie Strandboge <jamie@canonical.com>
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

In a recent change b932ed69: "virt-aa-helper: resolve yet to be created
paths" several cases with symlinks in paths were fixed, but it regressed
cases where the file being last element of the path was the actual link.

In the case of the last element being the symlink realpath can (and shall)
be called on the full path that was passed.

Examples would be zfs/lvm block devices like:
 <disk type='block' device='disk'>
    <driver name='qemu' type='raw'/>
    <source dev='/dev/mapper/testlvm-testvol1'/>
    <target dev='vdd' bus='virtio'/>
 </disk>
With the target being:
 /dev/mapper/testlvm-testvol1 -> ../dm-0

That currently is rendered as
 "/dev/mapper/testlvm-testvol1" rwk,
but instead should be (and is with the fix):
 "/dev/dm-0" rwk,

Fixes: b932ed69: "virt-aa-helper: resolve yet to be created paths"
Fixes: https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/1756394Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

We're freeing individual items in it but not the array itself.

==19200== 40 bytes in 1 blocks are definitely lost in loss record 847 of 1,059
==19200==    at 0x4C2D12F: realloc (vg_replace_malloc.c:785)
==19200==    by 0x52C5532: virReallocN (viralloc.c:245)
==19200==    by 0x52C5628: virExpandN (viralloc.c:294)
==19200==    by 0x52C58FC: virInsertElementsN (viralloc.c:436)
==19200==    by 0x542856B: virSecurityDACChownListAppend (security_dac.c:115)
==19200==    by 0x54286B4: virSecurityDACTransactionAppend (security_dac.c:167)
==19200==    by 0x542902F: virSecurityDACSetOwnershipInternal (security_dac.c:560)
==19200==    by 0x54295D6: virSecurityDACSetOwnership (security_dac.c:650)
==19200==    by 0x542AEE0: virSecurityDACSetInputLabel (security_dac.c:1472)
==19200==    by 0x542B61D: virSecurityDACSetAllLabel (security_dac.c:1693)
==19200==    by 0x542DD67: virSecurityManagerSetAllLabel (security_manager.c:869)
==19200==    by 0x54279C2: virSecurityStackSetAllLabel (security_stack.c:361)
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

In certain cases a xml contains paths that do not yet exist, but
are valid as qemu will create them later on - for example
vhostuser mode=server sockets.

In any such cases so far the check to virFileExists failed and due to
that the paths stayed non-resolved in regard to symlinks.

But for apparmor those non-resolved rules are non functional as they
are evaluated after resolving any symlinks.

Therefore for non-existent files and partially non-existent paths
resolve as much as possible to get valid rules.

Example:
   <interface type='vhostuser'>
       <model type='virtio'/>
       <source type='unix' path='/var/run/symlinknet' mode='server'/>
   </interface>

Got rendered as:
  "/var/run/symlinknet" rw,

But correct with "/var/run" being a symlink to "/run" is:
  "/run/symlinknet" rw,
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Acked-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Ensure all enum cases are listed in switch statements.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The QEMU driver loadable module needs to be able to resolve all ELF
symbols it references against libvirt.so. Some of its symbols can only
be resolved against the storage_driver.so loadable module which creates
a hard dependancy between them. By moving the storage file backend
framework into the util directory, this gets included directly in the
libvirt.so library. The actual backend implementations are still done as
loadable modules, so this doesn't re-add deps on gluster libraries.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virt-aa-helper fails to parse the xmls with the memory/cpu
hotplug features or user assigned aliases. Set the features in
xmlopt->config for the parsing to succeed.
Signed-off-by: NShivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Tested-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Reviewed-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

This is now covered by DomainSetPathLabel being implemented in apparmor.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Since 1b4f66ec "security: introduce virSecurityManager
(Set|Restore)ChardevLabel" this is a public API of security manager.

Implementing this in apparmor avoids miss any rules that should be
added for devices labeled via these calls.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

virSecurityManagerDomainSetPathLabel is used to make a path known
to the security modules, but today is used interchangably for
 - paths to files/dirs to be accessed directly
 - paths to a dir, but the access will actually be to files therein

Depending on the security module it is important to know which of
these types it will be.

The argument allowSubtree augments the call to the implementations of
DomainSetPathLabel that can - per security module - decide if extra
actions shall be taken.

For now dac/selinux handle this as before, but apparmor will make
use of it to add a wildcard to the path that was passed.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This came up in discussions around huge pages, but it will cover
more per guest paths that should be added to the guests apparmor profile:
 - keys via qemuDomainWriteMasterKeyFile
 - per domain dirs via qemuProcessMakeDir
 - memory backing paths via qemuProcessBuildDestroyMemoryPathsImpl
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

SELinux and DAC drivers already have both functions but they were not
exported as public API of security manager.
Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

Export the existing DAC and SELinux for separate use and introduce
functions for stack, nop and the security manager.

Right-aligning backslashes when defining macros or using complex
commands in Makefiles looks cute, but as soon as any changes is
required to the code you end up with either distractingly broken
alignment or unnecessarily big diffs where most of the changes
are just pushing all backslashes a few characters to one side.

Generated using

  $ git grep -El '[[:blank:]][[:blank:]]\\$' | \
    grep -E '*\.([chx]|am|mk)$$' | \
    while read f; do \
      sed -Ei 's/[[:blank:]]*[[:blank:]]\\$/ \\/g' "$f"; \
    done
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>

Until now we ignored user-provided backing chains and while detecting
the code inherited labels of the parent device. With user provided
chains we should keep this functionality, so label of the parent image
in the backing chain will be applied if an image-specific label is not
present.

Until now we ignored user-provided backing chains and while detecting
the code inherited labels of the parent device. With user provided
chains we should keep this functionality, so label of the parent image
in the backing chain will be applied if an image-specific label is not
present.

virSecuritySELinuxSetImageLabelInternal assigns different labels to
backing chain members than to the parent image. This was done via the
'first' flag. Convert it to passing in pointer to the parent
virStorageSource. This will allow us to use the parent virStorageSource
in further changes.

Some globbing chars in the domain name could be used to break out of
apparmor rules, so lets forbid these when in virt-aa-helper.

Also adding a test to ensure all those cases were detected as bad char.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Hot-adding disks does not parse the full XML to generate apparmor rules.
Instead it uses -f <PATH> to append a generic rule for that file path.

580cdaa7: "virt-aa-helper: locking disk files for qemu 2.10" implemented
the qemu 2.10 requirement to allow locking on disks images that are part of
the domain xml.

But on attach-device a user will still trigger an apparmor deny by going
through virt-aa-helper -f, to fix that add the lock "k" permission to the
append file case of virt-aa-helper.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Add helpers that will simplify checking if a backing file is valid or
whether it has backing store. The helper virStorageSourceIsBacking
returns true if the given virStorageSource is a valid backing store
member. virStorageSourceHasBacking returns true if the virStorageSource
has a backing store child.

Adding these functions creates a central points for further refactors.

To avoid any issues later on if paths ever change (unlikely but
possible) and to match the style of other generated rules the paths
of the static rules have to be quoted as well.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

libvirt allows spaces in vm names, there were issues in the past but it
seems not removed so the assumption has to be that spaces are continuing
to be allowed.

Therefore virt-aa-helper should not reject spaces in vm names anymore if
it is going to be refused causing issues then the parser or xml schema
should do so.
Apparmor rules are in quotes, so a space in a path based on the name works.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

If users only specified vendor&product (the common case) then parsing
the xml via virDomainHostdevSubsysUSBDefParseXML would only set these.
Bus and Device would much later be added when the devices are prepared
to be added.

Due to that a hot-add of a usb hostdev works as the device is prepared
and virt-aa-helper processes the new internal xml. But on an initial
guest start at the time virt-aa-helper renders the apparmor rules the
bus/device id's are not set yet:

p ctl->def->hostdevs[0]->source.subsys.u.usb
$12 = {autoAddress = false, bus = 0, device = 0, vendor = 1921, product
= 21888}

That causes rules to be wrong:
  "/dev/bus/usb/000/000" rw,

The fix calls virHostdevFindUSBDevice after reading the XML from
virt-aa-helper to only add apparmor rules for devices that could be found
and now are fully known to be able to write the rule correctly.

It uncondtionally sets virHostdevFindUSBDevice mandatory attribute as
adding an apparmor rule for a device not found makes no sense no matter
what startup policy it has set.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Seeing a log message saying 'flags=93' is ambiguous & confusing unless
you happen to know that libvirt always prints flags as hex.  Change our
debug messages so that they always add a '0x' prefix when printing flags,
and '0' prefix when printing mode. A few other misc places gain a '0x'
prefix in error messages too.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

instead of only unloading it. This makes sure old profiles don't pile up
in /etc/apparmor.d/libvirt and we get updates to modified templates on
VM restart.
Reviewed-by: NJim Fehlig <jfehlig@suse.com>

Things moved again, sigh.
Reviewed-By: NJamie Strandboge <jamie@canonical.com>
Michal Privoznik <mprivozn@redhat.com>

For a logged in user this a path like /dev/dri/renderD128 will have
default ownership root:video which won't work for the qemu:qemu user,
so we need to chown it.

We only do this when mount namespaces are enabled in the qemu driver,
so the chown'ing doesn't interfere with other users of the shared
render node path

https://bugzilla.redhat.com/show_bug.cgi?id=1460804

The VIR_SECURITY_MANAGER_MOUNT_NAMESPACE flag informs the DAC driver
if mount namespaces are in use for the VM. Will be used for future
changes.

Wire it up in the qemu driver

When security drivers are active but confinement is not enabled,
there is no need to autogenerate <seclabel> elements when starting
a domain def that contains no <seclabel> elements. In fact,
autogenerating the elements can result in needless save/restore and
migration failures when the security driver is not active on the
restore/migration target.

This patch changes the virSecurityManagerGenLabel function in
src/security_manager.c to only autogenerate a <seclabel> element
if none is already defined for the domain *and* default
confinement is enabled. Otherwise the needless <seclabel>
autogeneration is skipped.

Resolves: https://bugzilla.opensuse.org/show_bug.cgi?id=1051017

Testing qemu-2.10-rc3 shows issues like:
  qemu-system-aarch64: -drive file=/home/ubuntu/vm-start-stop/vms/
  7936-0_CODE.fd,if=pflash,format=raw,unit=1: Failed to unlock byte 100

There is an apparmor deny due to qemu now locking those files:
 apparmor="DENIED" operation="file_lock" [...]
 name="/home/ubuntu/vm-start-stop/vms/7936-0_CODE.fd"
 name="/var/lib/uvtool/libvirt/images/kvmguest-artful-normal.qcow"
 [...] comm="qemu-system-aarch64" requested_mask="k" denied_mask="k"

The profile needs to allow locking for loader and nvram files via
the locking (k) rule.
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Testing qemu-2.10-rc2 shows issues like:
  qemu-system-x86_64: -drive file=/var/lib/uvtool/libvirt/images/kvmguest- \
  artful-normal.qcow,format=qcow2,if=none,id=drive-virtio-disk0:
  Failed to lock byte 100

It seems the following qemu commit changed the needs for the backing
image rules:

(qemu) commit 244a5668106297378391b768e7288eb157616f64
Author: Fam Zheng <famz@redhat.com>
    file-posix: Add image locking to perm operations

The block appears as:
 apparmor="DENIED" operation="file_lock" [...]
 name="/var/lib/uvtool/libvirt/images/kvmguest-artful-normal.qcow"
 [...] comm="qemu-system-x86" requested_mask="k" denied_mask="k"

With that qemu change in place the rules generated for the image
and backing files need the allowance to also lock (k) the files.

Disks are added via add_file_path and with this fix rules now get
that permission, but no other rules are changed, example:
  -  "/var/lib/uvtool/libvirt/images/kvmguest-artful-normal-a2.qcow" rw,
  +  "/var/lib/uvtool/libvirt/images/kvmguest-artful-normal-a2.qcow" rwk
Signed-off-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>

Signed-off-by: NPavel Hrdina <phrdina@redhat.com>

In commit 5e515b54 I've attempted to fix the inability to access
storage from the apparmor helper program by linking with the storage
driver. By linking with the .so the linker complains that it's not
portable. Fix this by loading the module dynamically as we are supposed
to do.
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>

The refactor to split up storage driver into modules broke the apparmor
helper program, since that did not initialize the storage driver
properly and thus detection of the backing chain could not work.

Register the storage driver backends explicitly. Unfortunately it's now
necessary to link with the full storage driver to satisfy dependencies
of the loadable modules.
Reviewed-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Reported-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>
Tested-by: NChristian Ehrhardt <christian.ehrhardt@canonical.com>