Refactor the code and reuse it to implement the functionality.

Refactor the existing code to allow re-using it for the per-image label
restore too.

In the future we might need to track state of individual images. Move
the readonly and shared flags to the virStorageSource struct so that we
can keep them in a per-image basis.

I'm going to add functions that will deal with individual image files
rather than whole disks. Rename the security function to make room for
the new one.

I'm going to add functions that will deal with individual image files
rather than whole disks. Rename the security function to make room for
the new one.

Also remove one spurious ATTRIBUTE_UNUSED guarding the @migrated
argument.

The image labels are stored in the virStorageSource struct. Convert the
virDomainDiskDefGetSecurityLabelDef helper not to use the full disk def
and move it appropriately.

A network disk might actually be backed by local storage. Also the path
iterator actually handles networked disks well now so remove the code
that skips the labelling in dac and selinux security driver.

In "src/conf/domain_conf.h" there are many enum declarations. The
cleanup in this header filer was started, but it wasn't enough and
there are many other files that has enum variables declared. So, the
commit was starting to be big. This commit finish the cleanup in this
header file and in other files that has enum variables, parameters,
or functions declared.
Signed-off-by: NJulio Faracco <jcfaracco@gmail.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

In "src/conf/domain_conf.h" there are many enumerations (enum)
declarations to be converted as a typedef too. As mentioned before,
it's better to use a typedef for variable types, function types and
other usages. I think this file has most of those enum declarations
at "src/conf/". So, me and Eric Blake plan to keep the cleanups all
over the source code. This time, most of the files changed in this
commit are related to part of one file: "src/conf/domain_conf.h".
Signed-off-by: NJulio Faracco <jcfaracco@gmail.com>

With dynamic_ownership = 1 but no seclabels, RestoreChardevLabel
dereferences the NULL seclabel when checking if norelabel is set.

Remove this check, since it is already done in RestoreSecurityAllLabel
and if norelabel is set, RestoreChardevLabel is never called.

The domain definition is clearly used a few lines
below so there's no need to mark @def as unused.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The DAC driver ignores the relabel='no' attribute in chardev config

  <serial type='file'>
    <source path='/tmp/jim/test.file'>
      <seclabel model='dac' relabel='no'/>
    </source>
    <target port='0'/>
  </serial>

This patch avoids labeling chardevs when relabel='no' is specified.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

When relabel='no' at the domain level, there is no need to call
the hostdev relabeling functions.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

https://bugzilla.redhat.com/show_bug.cgi?id=999301

The DAC driver ignores the relabel='no' attribute in disk config

  <disk type='file' device='floppy'>
    <driver name='qemu' type='raw'/>
    <source file='/some/path/floppy.img'>
      <seclabel model='dac' relabel='no'/>
    </source>
    <target dev='fda' bus='fdc'/>
    <readonly/>
  </disk>

This patch avoid labeling disks when relabel='no' is specified.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

If relabel='no' at the domain level, no need to attempt relabeling
in virSecurityDAC{Set,Restore}SecurityAllLabel().
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Currently, the DAC security driver passes callback data as

    void params[2];
    params[0] = mgr;
    params[1] = def;

Clean this up by defining a structure for passing the callback
data.  Moreover, there's no need to pass the whole virDomainDef
in the callback as the only thing needed in the callbacks is
virSecurityLabelDefPtr.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

In switch statements, use enum types since it is safer when
adding new items to the enum.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Annotate some static function parameters with ATTRIBUTE_NONNULL
and remove checks for NULL inputs.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NJim Fehlig <jfehlig@suse.com>

Remove ATTRIBUTE_UNUSED on several function parameters that are
actually used.

The code in virstoragefile.c is getting more complex as I
consolidate backing chain handling code.  But for the setuid
virt-login-shell, we don't need to crawl backing chains.  It's
easier to audit things for setuid security if there are fewer
files involved, so this patch moves the one function that
virFileOpen() was actually relying on to also live in virfile.c.

* src/util/virstoragefile.c (virStorageFileIsSharedFS)
(virStorageFileIsSharedFSType): Move...
* src/util/virfile.c (virFileIsSharedFS, virFileIsSharedFSType):
...to here, and rename.
(virFileOpenAs): Update caller.
* src/security/security_selinux.c
(virSecuritySELinuxSetFileconHelper)
(virSecuritySELinuxSetSecurityAllLabel)
(virSecuritySELinuxRestoreSecurityImageLabelInt): Likewise.
* src/security/security_dac.c
(virSecurityDACRestoreSecurityImageLabelInt): Likewise.
* src/qemu/qemu_driver.c (qemuOpenFileAs): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsSafe): Likewise.
* src/util/virstoragefile.h: Adjust declarations.
* src/util/virfile.h: Likewise.
* src/libvirt_private.syms (virfile.h, virstoragefile.h): Move
symbols as appropriate.
Signed-off-by: NEric Blake <eblake@redhat.com>

A continuation of the migration of disk details to virstoragefile.
This patch moves a single enum, but converting the name has quite
a bit of fallout.

* src/conf/domain_conf.h (virDomainDiskType): Move...
* src/util/virstoragefile.h (virStorageType): ...and rename.
* src/bhyve/bhyve_command.c (bhyveBuildDiskArgStr)
(virBhyveProcessBuildLoadCmd): Update clients.
* src/conf/domain_conf.c (virDomainDiskSourceDefParse)
(virDomainDiskDefParseXML, virDomainDiskSourceDefFormatInternal)
(virDomainDiskDefFormat, virDomainDiskGetActualType)
(virDomainDiskDefForeachPath, virDomainDiskSourceIsBlockType):
Likewise.
* src/conf/snapshot_conf.h (_virDomainSnapshotDiskDef): Likewise.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML)
(virDomainSnapshotAlignDisks, virDomainSnapshotDiskDefFormat):
Likewise.
* src/esx/esx_driver.c (esxAutodetectSCSIControllerModel)
(esxDomainDefineXML): Likewise.
* src/locking/domain_lock.c (virDomainLockManagerAddDisk):
Likewise.
* src/lxc/lxc_controller.c
(virLXCControllerSetupLoopDeviceDisk)
(virLXCControllerSetupNBDDeviceDisk)
(virLXCControllerSetupLoopDevices, virLXCControllerSetupDisk):
Likewise.
* src/parallels/parallels_driver.c (parallelsGetHddInfo):
Likewise.
* src/phyp/phyp_driver.c (phypDiskType): Likewise.
* src/qemu/qemu_command.c (qemuGetDriveSourceString)
(qemuDomainDiskGetSourceString, qemuBuildDriveStr)
(qemuBuildCommandLine, qemuParseCommandLineDisk)
(qemuParseCommandLine): Likewise.
* src/qemu/qemu_conf.c (qemuCheckSharedDevice)
(qemuTranslateDiskSourcePool)
(qemuTranslateSnapshotDiskSourcePool): Likewise.
* src/qemu/qemu_domain.c (qemuDomainDeviceDefPostParse)
(qemuDomainDetermineDiskChain): Likewise.
* src/qemu/qemu_driver.c (qemuDomainGetBlockInfo)
(qemuDomainSnapshotPrepareDiskExternalBackingInactive)
(qemuDomainSnapshotPrepareDiskExternalBackingActive)
(qemuDomainSnapshotPrepareDiskExternalOverlayActive)
(qemuDomainSnapshotPrepareDiskExternalOverlayInactive)
(qemuDomainSnapshotPrepareDiskInternal)
(qemuDomainSnapshotPrepare)
(qemuDomainSnapshotCreateSingleDiskActive): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeEjectableMedia):
Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsSafe): Likewise.
* src/security/security_apparmor.c
(AppArmorRestoreSecurityImageLabel)
(AppArmorSetSecurityImageLabel): Likewise.
* src/security/security_dac.c (virSecurityDACSetSecurityImageLabel)
(virSecurityDACRestoreSecurityImageLabelInt)
(virSecurityDACSetSecurityAllLabel): Likewise.
* src/security/security_selinux.c
(virSecuritySELinuxRestoreSecurityImageLabelInt)
(virSecuritySELinuxSetSecurityImageLabel)
(virSecuritySELinuxSetSecurityAllLabel): Likewise.
* src/storage/storage_backend.c (virStorageFileBackendForType):
Likewise.
* src/storage/storage_backend_fs.c (virStorageFileBackendFile)
(virStorageFileBackendBlock): Likewise.
* src/storage/storage_backend_gluster.c
(virStorageFileBackendGluster): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc, vboxAttachDrives)
(vboxDomainAttachDeviceImpl, vboxDomainDetachDevice): Likewise.
* src/vmware/vmware_conf.c (vmwareVmxPath): Likewise.
* src/vmx/vmx.c (virVMXParseDisk, virVMXFormatDisk)
(virVMXFormatFloppy): Likewise.
* src/xenxs/xen_sxpr.c (xenParseSxprDisks, xenParseSxpr)
(xenFormatSxprDisk): Likewise.
* src/xenxs/xen_xm.c (xenParseXM, xenFormatXMDisk): Likewise.
* tests/securityselinuxlabeltest.c (testSELinuxLoadDef):
Likewise.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virstoragefile.h): ...as appropriate.
Signed-off-by: NEric Blake <eblake@redhat.com>

Part of a series of cleanups to use new accessor methods.

* src/security/security_dac.c (virSecurityDACSetSecurityImageLabel)
(virSecurityDACRestoreSecurityImageLabelInt)
(virSecurityDACSetSecurityAllLabel): Use accessors.
* src/security/security_selinux.c
(virSecuritySELinuxRestoreSecurityImageLabelInt)
(virSecuritySELinuxSetSecurityImageLabel)
(virSecuritySELinuxSetSecurityAllLabel): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The @def is clearly used just a few lines below. There's no need to use
ATTRIBUTE_UNUSED for it.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

To support passing the path of the test data to the utils, one
more argument is added to virSCSIDeviceGetSgName,
virSCSIDeviceGetDevName, and virSCSIDeviceNew, and the related
code is changed accordingly.

Later tests for the scsi utils will be based on this patch.
Signed-off-by: NOsier Yang <jyang@redhat.com>

Unlike the host devices of other types, SCSI host device XML supports
"shareable" tag. This patch introduces it for the virSCSIDevice struct
for a later patch use (to detect if the SCSI device is shareable when
preparing the SCSI host device in QEMU driver).

To ensure proper processing by virGetUserID() and virGetGroupID()
of a uid/gid add a "+" prior to the uid/gid to denote it's really
a uid/gid for the label.

virSecurityManagerGetBaseLabel queries the default settings used by
a security model.
Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>

Merge the functions 'virSecurityDACSetUser' and
'virSecurityDACSetGroup' into 'virSecurityDACSetUserAndGroup'.
Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>

Commit 29fe5d74 (released in 1.1.1) introduced a latent problem
for any caller of virSecurityManagerSetProcessLabel and where
the domain already had a uid:gid label to be parsed.  Such a
setup would collect the list of supplementary groups during
virSecurityManagerPreFork, but then ignores that information,
and thus fails to call setgroups() to adjust the supplementary
groups of the process.

Upstream does not use virSecurityManagerSetProcessLabel for
qemu (it uses virSecurityManagerSetChildProcessLabel instead),
so this problem remained latent until backporting the initial
commit into v0.10.2-maint (commit c061ff5e, released in 0.10.2.7),
where virSecurityManagerSetChildProcessLabel has not been
backported.  As a result of using a different code path in the
backport, attempts to start a qemu domain that runs as qemu:qemu
will end up with supplementary groups unchanged from the libvirtd
parent process, rather than the desired supplementary groups of
the qemu user.  This can lead to failure to start a domain
(typical Fedora setup assigns user 107 'qemu' to both group 107
'qemu' and group 36 'kvm', so a disk image that is only readable
under kvm group rights is locked out).  Worse, it is a security
hole (the qemu process will inherit supplemental group rights
from the parent libvirtd process, which means it has access
rights to files owned by group 0 even when such files should
not normally be visible to user qemu).

LXC does not use the DAC security driver, so it is not vulnerable
at this time.  Still, it is better to plug the latent hole on
the master branch first, before cherry-picking it to the only
vulnerable branch v0.10.2-maint.

* src/security/security_dac.c (virSecurityDACGetIds): Always populate
groups and ngroups, rather than only when no label is parsed.
Signed-off-by: NEric Blake <eblake@redhat.com>

Parsing 'user:group' is useful even outside the DAC security driver,
so expose the most abstract function which has no DAC security driver
bits in itself.

Commit 75c12564 states that virGetGroupList must not be called
between fork and exec, then commit ee777e99 promptly violated
that for lxc's use of virSecurityManagerSetProcessLabel.  Hoist
the supplemental group detection to the time that the security
manager needs to fork.  Qemu is safe, as it uses
virSecurityManagerSetChildProcessLabel which in turn uses
virCommand to determine supplemental groups.

This does not fix the fact that virSecurityManagerSetProcessLabel
calls virSecurityDACParseIds calls parseIds which eventually
calls getpwnam_r, which also violates fork/exec async-signal-safe
safety rules, but so far no one has complained of hitting
deadlock in that case.

* src/security/security_dac.c (_virSecurityDACData): Track groups
in private data.
(virSecurityDACPreFork): New function, to set them.
(virSecurityDACClose): Clean up new fields.
(virSecurityDACGetIds): Alter signature.
(virSecurityDACSetSecurityHostdevLabelHelper)
(virSecurityDACSetChardevLabel, virSecurityDACSetProcessLabel)
(virSecurityDACSetChildProcessLabel): Update callers.
Signed-off-by: NEric Blake <eblake@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=964358

POSIX states that multi-threaded apps should not use functions
that are not async-signal-safe between fork and exec, yet we
were using getpwuid_r and initgroups.  Although rare, it is
possible to hit deadlock in the child, when it tries to grab
a mutex that was already held by another thread in the parent.
I actually hit this deadlock when testing multiple domains
being started in parallel with a command hook, with the following
backtrace in the child:

 Thread 1 (Thread 0x7fd56bbf2700 (LWP 3212)):
 #0  __lll_lock_wait ()
     at ../nptl/sysdeps/unix/sysv/linux/x86_64/lowlevellock.S:136
 #1  0x00007fd5761e7388 in _L_lock_854 () from /lib64/libpthread.so.0
 #2  0x00007fd5761e7257 in __pthread_mutex_lock (mutex=0x7fd56be00360)
     at pthread_mutex_lock.c:61
 #3  0x00007fd56bbf9fc5 in _nss_files_getpwuid_r (uid=0, result=0x7fd56bbf0c70,
     buffer=0x7fd55c2a65f0 "", buflen=1024, errnop=0x7fd56bbf25b8)
     at nss_files/files-pwd.c:40
 #4  0x00007fd575aeff1d in __getpwuid_r (uid=0, resbuf=0x7fd56bbf0c70,
     buffer=0x7fd55c2a65f0 "", buflen=1024, result=0x7fd56bbf0cb0)
     at ../nss/getXXbyYY_r.c:253
 #5  0x00007fd578aebafc in virSetUIDGID (uid=0, gid=0) at util/virutil.c:1031
 #6  0x00007fd578aebf43 in virSetUIDGIDWithCaps (uid=0, gid=0, capBits=0,
     clearExistingCaps=true) at util/virutil.c:1388
 #7  0x00007fd578a9a20b in virExec (cmd=0x7fd55c231f10) at util/vircommand.c:654
 #8  0x00007fd578a9dfa2 in virCommandRunAsync (cmd=0x7fd55c231f10, pid=0x0)
     at util/vircommand.c:2247
 #9  0x00007fd578a9d74e in virCommandRun (cmd=0x7fd55c231f10, exitstatus=0x0)
     at util/vircommand.c:2100
 #10 0x00007fd56326fde5 in qemuProcessStart (conn=0x7fd53c000df0,
     driver=0x7fd55c0dc4f0, vm=0x7fd54800b100, migrateFrom=0x0, stdin_fd=-1,
     stdin_path=0x0, snapshot=0x0, vmop=VIR_NETDEV_VPORT_PROFILE_OP_CREATE,
     flags=1) at qemu/qemu_process.c:3694
 ...

The solution is to split the work of getpwuid_r/initgroups into the
unsafe portions (getgrouplist, called pre-fork) and safe portions
(setgroups, called post-fork).

* src/util/virutil.h (virSetUIDGID, virSetUIDGIDWithCaps): Adjust
signature.
* src/util/virutil.c (virSetUIDGID): Add parameters.
(virSetUIDGIDWithCaps): Adjust clients.
* src/util/vircommand.c (virExec): Likewise.
* src/util/virfile.c (virFileAccessibleAs, virFileOpenForked)
(virDirCreate): Likewise.
* src/security/security_dac.c (virSecurityDACSetProcessLabel):
Likewise.
* src/lxc/lxc_container.c (lxcContainerSetID): Likewise.
* configure.ac (AC_CHECK_FUNCS_ONCE): Check for setgroups, not
initgroups.
Signed-off-by: NEric Blake <eblake@redhat.com>

Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

I realized after the fact that it's probably better in the long run to
give this function a name that matches the name of the link used in
sysfs to hold the group (iommu_group).

I'm changing it now because I'm about to add several more functions
that deal with iommu groups.