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

When changing to virArch, the virt-aa-helper.c file was not
completely changed. The vahControl struct was left with a
char *arch field, instead of virArch arch field.

Convert the host capabilities and domain config structs to
use the virArch datatype. Update the parsers and all drivers
to take account of datatype change
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The SELinux security driver needs to learn to label storage/misc
hostdev devices for LXC
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Prepare to support different types of hostdevs by refactoring
the current SELinux security driver code
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When LXC labels USB devices during hotplug, it is running in
host context, so it needs to pass in a vroot path to the
container root.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virSecurityManager{Set,Restore}AllLabel methods are invoked
at domain startup/shutdown to relabel resources associated with
a domain. This works fine with QEMU, but with LXC they are in
fact both currently no-ops since LXC does not support disks,
hostdevs, or kernel/initrd files. Worse, when LXC gains support
for disks/hostdevs, they will do the wrong thing, since they
run in host context, not container context. Thus this patch
turns then into a formal no-op when used with LXC. The LXC
controller will call out to specific security manager labelling
APIs as required during startup.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The current SELinux policy only works for KVM guests, since
TCG requires the 'execmem' privilege. There is a 'virt_use_execmem'
boolean to turn this on globally, but that is unpleasant for users.
This changes libvirt to automatically use a new 'svirt_tcg_t'
context for TCG based guests. This obsoletes the previous
boolean tunable and makes things 'just work(tm)'

Since we can't assume we run with new enough policy, I also
make us log a warning message (once only) if we find the policy
lacks support. In this case we fallback to the normal label and
expect users to set the boolean tunable
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In the case of an OOM error in virDomainDefGetSecurityLabelDef, secdef
is set to NULL, then dereferenced while printing the debug message.

When using vnc gaphics over a unix socket, virt-aa-helper needs to provide
access for the qemu domain to access the sockfile.
Signed-off-by: NSerge Hallyn <serge.hallyn@ubuntu.com>

When a qemu domain is backed by huge pages, apparmor needs to grant the domain
rw access to files under the hugetlbfs mount point.  Add a hook, called in
qemu_process.c, which ends up adding the read-write access through
virt-aa-helper.  Qemu will be creating a randomly named file under the
mountpoint and unlinking it as soon as it has mmap()d it, therefore we
cannot predict the full pathname, but for the same reason it is generally
safe to provide access to $path/**.
Signed-off-by: NSerge Hallyn <serge.hallyn@ubuntu.com>

The impls of virSecurityManagerGetMountOptions had no way to
return errors, since the code was treating 'NULL' as a success
value. This is somewhat pointless, since the calling code did
not want NULL in the first place and has to translate it into
the empty string "". So change the code so that the impls can
return "" directly, allowing use of NULL for error reporting
once again
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

For S390, the default console target type cannot be of type 'serial'.
It is necessary to at least interpret the 'arch' attribute
value of the os/type element to produce the correct default type.

Therefore we need to extend the signature of defaultConsoleTargetType
to account for architecture. As a consequence all the drivers
supporting this capability function must be updated.

Despite the amount of changed files, the only change in behavior is
that for S390 the default console target type will be 'virtio'.

N.B.: A more future-proof approach could be to to use hypervisor
specific capabilities to determine the best possible console type.
For instance one could add an opaque private data pointer to the
virCaps structure (in case of QEMU to hold capsCache) which could
then be passed to the defaultConsoleTargetType callback to determine
the console target type.
Seems to be however a bit overengineered for the use case...
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

The libvirt coding standard is to use 'function(...args...)'
instead of 'function (...args...)'. A non-trivial number of
places did not follow this rule and are fixed in this patch.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Recent storage patches changed signature of virStorageFileGetMetadata
and replaced chain with backingChain in virDomainDiskDef.

When restoring selinux labels after a VM is stopped, any non-standard
path that doesn't have a default selinux label causes the process
to stop and exit early. This isn't really an error condition IMO.

Of course the selinux API could be erroring for some other reason
but hopefully that's rare enough to not need explicit handling.

Common example here is storing disk images in a non-standard location
like under /mnt.

Reported by Michal Privoznik.

* src/security/security_dac.c (virSecurityDACGenLabel): Use
correct format.

Fixes a build failure on cygwin:
cc1: warnings being treated as errors
security/security_dac.c: In function 'virSecurityDACSetProcessLabel':
security/security_dac.c:862:5: error: format '%u' expects type 'unsigned int', but argument 7 has type 'uid_t' [-Wformat]
security/security_dac.c:862:5: error: format '%u' expects type 'unsigned int', but argument 8 has type 'gid_t' [-Wformat]

* src/security/security_dac.c (virSecurityDACSetProcessLabel)
(virSecurityDACGenLabel): Use proper casts.

We used to walk the backing file chain at least twice per disk,
once to set up cgroup device whitelisting, and once to set up
security labeling.  Rather than walk the chain every iteration,
which possibly includes calls to fork() in order to open root-squashed
NFS files, we can exploit the cache of the previous patch.

* src/conf/domain_conf.h (virDomainDiskDefForeachPath): Alter
signature.
* src/conf/domain_conf.c (virDomainDiskDefForeachPath): Require caller
to supply backing chain via disk, if recursion is desired.
* src/security/security_dac.c
(virSecurityDACSetSecurityImageLabel): Adjust caller.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityImageLabel): Likewise.
* src/security/virt-aa-helper.c (get_files): Likewise.
* src/qemu/qemu_cgroup.c (qemuSetupDiskCgroup)
(qemuTeardownDiskCgroup): Likewise.
(qemuSetupCgroup): Pre-populate chain.

In commit 9674f2c6, I forgot to change
selabel_lookup with the other functions, so this one-liner does exactly
that.

BZ:https://bugzilla.redhat.com/show_bug.cgi?id=851981
When using macvtap, a character device gets first created by
kernel with name /dev/tapN, its selinux context is:
system_u:object_r:device_t:s0

Shortly, when udev gets notification when new file is created
in /dev, it will then jump in and relabel this file back to the
expected default context:
system_u:object_r:tun_tap_device_t:s0

There is a time gap happened.
Sometimes, it will have migration failed, AVC error message:
type=AVC msg=audit(1349858424.233:42507): avc:  denied  { read write } for
pid=19926 comm="qemu-kvm" path="/dev/tap33" dev=devtmpfs ino=131524
scontext=unconfined_u:system_r:svirt_t:s0:c598,c908
tcontext=system_u:object_r:device_t:s0 tclass=chr_file

This patch will label the tapfd device before qemu process starts:
system_u:object_r:tun_tap_device_t:MCS(MCS from seclabel->label)

We are currently able to work only with non-translated SELinux
contexts, but we are using functions that work with translated
contexts throughout the code.  This patch swaps all SELinux context
translation relative calls with their raw sisters to avoid parsing
problems.

The problems can be experienced with mcstrans for example.  The
difference is that if you have translations enabled (yum install
mcstrans; service mcstrans start), fgetfilecon_raw() will get you
something like 'system_u:object_r:virt_image_t:s0', whereas
fgetfilecon() will return 'system_u:object_r:virt_image_t:SystemLow'
that we cannot parse.

I was trying to confirm that the _raw variants were here since the dawn of
time, but the only thing I see now is that it was imported together in
the upstream repo [1] from svn, so before 2008.

Thanks Laurent Bigonville for finding this out.

[1] http://oss.tresys.com/git/selinux.git

All USB device lookup functions emit an error when they cannot find the
requested device. With this patch, their caller can choose if a missing
device is an error or normal condition.

The functions virGetUserID and virGetGroupID are now able to parse
user/group names and IDs in a similar way to coreutils' chown. So, user
and group parsing in security_dac can be simplified.

The DAC driver is missing parsing of group and user names for DAC labels
and currently just parses uid and gid. This patch extends it to support
names, so the following security label definition is now valid:

  <seclabel type='static' model='dac' relabel='yes'>
      <label>qemu:qemu</label>
      <imagelabel>qemu:qemu</imagelabel>
  </seclabel>

When it tries to parse an owner or a group, it first tries to resolve it as
a name, if it fails or it's an invalid user/group name then it tries to
parse it as an UID or GID. A leading '+' can also be used for both owner and
group to force it to be parsed as IDs, so the following example is also
valid:

  <seclabel type='static' model='dac' relabel='yes'>
      <label>+101:+101</label>
      <imagelabel>+101:+101</imagelabel>
  </seclabel>

This ensures that UID 101 and GUI 101 will be used instead of an user or
group named "101".

This allows the user to control labelling of each character device
separately (the default is to inherit from the VM).
Signed-off-by: NRichard W.M. Jones <rjones@redhat.com>

https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/

The DAC security driver silently ignored errors when parsing the DAC
label and used default values instead.

With a domain containing the following label definition:

<seclabel type='static' model='dac' relabel='yes'>
  <label>sdfklsdjlfjklsdjkl</label>
</seclabel>

the domain would start normaly but the disk images would be still owned
by root and no error was displayed.

This patch changes the behavior if the parsing of the label fails (note
that a not present label is not a failure and in this case the default
label should be used) the error isn't masked but is raised that causes
the domain start to fail with a descriptive error message:

virsh #  start tr
error: Failed to start domain tr
error: internal error invalid argument: failed to parse DAC seclabel
'sdfklsdjlfjklsdjkl' for domain 'tr'

I also changed the error code to "invalid argument" from "internal
error" and tweaked the various error messages to contain correct and
useful information.

Recent changes in the security driver discarded changes that fixed
labeling un-confined guests.

If no 'security_driver' config option was set, then the code
just loaded the 'dac' security driver. This is a regression
on previous behaviour, where we would probe for a possible
security driver. ie default to SELinux if available.

This changes things so that it 'security_driver' is not set,
we once again do probing. For simplicity we also always
create the stack driver, even if there is only one driver
active.

The desired semantics are:

 - security_driver not set
     -> probe for selinux/apparmour/nop
     -> auto-add DAC driver
 - security_driver set to a string
     -> add that one driver
     -> auto-add DAC driver
 - security_driver set to a list
     -> add all drivers in list
     -> auto-add DAC driver

It is not allowed, or possible to specify 'dac' in the
security_driver config param, since that is always
enabled.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>