Remove all the QEMU driver calls for setting file ownership and
process uid/gid. Instead wire in the QEMU DAC security driver,
stacking it ontop of the primary SELinux/AppArmour driver.

* qemu/qemu_driver.c: Switch over to new DAC security driver

This new security driver is responsible for managing UID/GID changes
to the QEMU process, and any files/disks/devices assigned to it.

* qemu/qemu_conf.h: Add flag for disabling automatic file permission
  changes
* qemu/qemu_security_dac.h, qemu/qemu_security_dac.c: New DAC driver
  for QEMU guests
* Makefile.am: Add new files

* qemu/qemu_conf.h: Add securityPrimaryDriver and
  securitySecondaryDriver fields to 'struct qemud_driver'
* Makefile.am: Add new files
* qemu/qemu_security_stacked.c, qemu/qemu_security_stacked.h: A
  simple stacked security driver

Pulling the disk labelling code out of the exec hook, and into
libvirtd will allow it to access shared state in the daemon. It
will also make debugging & error reporting easier / more reliable.

* qemu/qemu_driver.c: Move initial disk labelling calls up into
  libvirtd. Add cleanup of disk labels upon failure

If a VM fails to start, we can't simply free the security label
strings, we must call the domainReleaseSecurityLabel() method
otherwise the reserved 'mcs' level will be leaked in SElinux

* src/qemu/qemu_driver.c: Invoke domainReleaseSecurityLabel()
  when domain fails to start

The current security driver architecture has the following
split of logic

 * domainGenSecurityLabel

    Allocate the unique label for the domain about to be started

 * domainGetSecurityLabel

    Retrieve the current live security label for a process

 * domainSetSecurityLabel

    Apply the previously allocated label to the current process
    Setup all disk image / device labelling

 * domainRestoreSecurityLabel

    Restore the original disk image / device labelling.
    Release the unique label for the domain

The 'domainSetSecurityLabel' method is special because it runs
in the context of the child process between the fork + exec.

This is require in order to set the process label. It is not
required in order to label disks/devices though. Having the
disk labelling code run in the child process limits what it
can do.

In particularly libvirtd would like to remember the current
disk image label, and only change shared image labels for the
first VM to start. This requires use & update of global state
in the libvirtd daemon, and thus cannot run in the child
process context.

The solution is to split domainSetSecurityLabel into two parts,
one applies process label, and the other handles disk image
labelling. At the same time domainRestoreSecurityLabel is
similarly split, just so that it matches the style. Thus the
previous 4 methods are replaced by the following 6 new methods

 * domainGenSecurityLabel

    Allocate the unique label for the domain about to be started
    No actual change here.

 * domainReleaseSecurityLabel

   Release the unique label for the domain

 * domainGetSecurityProcessLabel

   Retrieve the current live security label for a process
   Merely renamed for clarity.

 * domainSetSecurityProcessLabel

   Apply the previously allocated label to the current process

 * domainRestoreSecurityAllLabel

    Restore the original disk image / device labelling.

 * domainSetSecurityAllLabel

    Setup all disk image / device labelling

The SELinux and AppArmour drivers are then updated to comply with
this new spec. Notice that the AppArmour driver was actually a
little different. It was creating its profile for the disk image
and device labels in the 'domainGenSecurityLabel' method, where as
the SELinux driver did it in 'domainSetSecurityLabel'. With the
new method split, we can have consistency, with both drivers doing
that in the domainSetSecurityAllLabel method.

NB, the AppArmour changes here haven't been compiled so may not
build.

The QEMU driver is doing 90% of the calls to check for static vs
dynamic labelling. Except it is forgetting todo so in many places,
in particular hotplug is mistakenly assigning disk labels. Move
all this logic into the security drivers themselves, so the HV
drivers don't have to think about it.

* src/security/security_driver.h: Add virDomainObjPtr parameter
  to virSecurityDomainRestoreHostdevLabel and to
  virSecurityDomainRestoreSavedStateLabel
* src/security/security_selinux.c, src/security/security_apparmor.c:
  Add explicit checks for VIR_DOMAIN_SECLABEL_STATIC and skip all
  chcon() code in those cases
* src/qemu/qemu_driver.c: Remove all checks for VIR_DOMAIN_SECLABEL_STATIC
  or VIR_DOMAIN_SECLABEL_DYNAMIC. Add missing checks for possibly NULL
  driver entry points.

Allows the initiator to use a variety of IQNs rather than just the
system IQN when creating iSCSI pools.
* docs/schemas/storagepool.rng: extends the syntax with <iqn name="..."/>
* src/conf/storage_conf.[ch]: read and stores the iqn name
* src/storage/storage_backend_iscsi.[ch]: implement the IQN selection
  when detected

* src/lxc/lxc_container.c src/lxc/lxc_controller.c src/lxc/lxc_driver.c
  src/network/bridge_driver.c src/qemu/qemu_driver.c
  src/uml/uml_driver.c: virFileMakePath returns 0 for success, or the
  value of errno on failure, so error checking should be to test
  if non-zero, not if lower than 0

Previously the uid/gid/mode in the xml was ignored when creating new
storage pool directories. This commit attempts to honor the requested
permissions, and spits out an error if it can't.

Note that when creating the directory, the rest of the path leading up
to the final element is created using current uid/gid/mode, and the
final element gets the settings from xml. It is NOT an error for the
directory to already exist; in this case, the perms for the existing
directory are just set (if necessary).

* src/storage/storage_backend_fs.c: update the virStorageBackendFileSystemBuild
  function to check the directory hierarchy separately then create the
  leaf directory with the right attributes

In order to avoid problems trying to chown files that were created by
root on a root-squashing nfs server, fork a new process that setuid's
to the desired uid before creating the file. (It's only done this way
if the pool containing the new volume is of type 'netfs', otherwise
the old method of creating the file followed by chown() is used.)

This changes the semantics of the "create_func" slightly - previously
it was assumed that this function just created the file, then the
caller would chown it to the desired uid. Now, create_func does both
operations.

There are multiple functions that can take on the role of create_func:

createFileDir - previously called mkdir(), now calls virDirCreate().
virStorageBackendCreateRaw - previously called open(),
                             now calls virFileCreate().
virStorageBackendCreateQemuImg - use virRunWithHook() to setuid/gid.
virStorageBackendCreateQcowCreate - same.
virStorageBackendCreateBlockFrom - preserve old behavior (but attempt
                                   chown when necessary even if not root)

* src/storage/storage_backend.[ch] src/storage/storage_backend_disk.c
  src/storage/storage_backend_fs.c src/storage/storage_backend_logical.c
  src/storage/storage_driver.c: change the create_func implementations,
  also propagate the pool information to be able to detect NETFS ones.

These functions create a new file or directory with the given
uid/gid. If the flag VIR_FILE_CREATE_AS_UID is given, they do this by
forking a new process, calling setuid/setgid in the new process, and
then creating the file. This is better than simply calling open then
fchown, because in the latter case, a root-squashing nfs server would
create the new file as user nobody, then refuse to allow fchown.

If VIR_FILE_CREATE_AS_UID is not specified, the simpler tactic of
creating the file/dir, then chowning is is used. This gives better
results in cases where the parent directory isn't on a root-squashing
NFS server, but doesn't give permission for the specified uid/gid to
create files. (Note that if the fork/setuid method fails to create the
file due to access privileges, the parent process will make a second
attempt using this simpler method.)

If the bit VIR_FILE_CREATE_ALLOW_EXIST is set in the flags, an
existing file/directory will not cause an error; in this case, the
function will simply set the permissions of the file/directory to
those requested. If VIR_FILE_CREATE_ALLOW_EXIST is not specified, an
existing file/directory is considered (and reported as) an error.

Return from both of these functions is 0 on success, or the value of
errno if there was a failure.

* src/util/util.[ch]: add the 2 new util functions

* src/util/util.[ch]: similar to virExecWithHook, but waits for child to
  exit. Useful for doing things like setuid after the fork but before the
  exec.

The test expected all environment variables copied in qemudBuildCommandLine
to have known values. So all of them have to be either set to a known value
or be unset. SDL_VIDEODRIVER and QEMU_AUDIO_DRV are not handled at all but
should be handled. Unset both, otherwise the test will fail if they are set
in the testing environment.

* src/qemu/qemu_conf.c: add a comment about copied environment variables
  and qemuxml2argvtest
* tests/qemuxml2argvtest.c: unset SDL_VIDEODRIVER and QEMU_AUDIO_DRV

* src/node_device/node_device_linux_sysfs.c (get_virtual_functions_linux):
Remove unnecessary closedir.  Spotted by Dave Allan.

* src/node_device/node_device_linux_sysfs.c(get_virtual_functions_linux):
Don't leak a DIR buffer and file descriptor on error path.

* src/conf/domain_conf.c (virDomainChrDefFormat): Plug a leak on
an error path, and at the same time, eliminate the need for a
"cleanup:" block.  Before, the "return -1" after the switch
would leak an "addr" string.  Now, by reversing the port,addr-
getting blocks we can free "addr" immediately and skip the goto.

The 'int virInterfaceIsActive()' method was directly returning the
value of the 'int active:1' bitfield in virIntefaceDefPtr. A bitfield
with a signed integer, will hold the values 0 and -1, not 0 and +1
as might be expected. This meant that virInterfaceIsActive() was
always returning -1 when the interface was active, not +1 & thus all
callers thought an error had occurred. To protect against this kind
of mistake again, change all bitfields to be unsigned ints

* daemon/libvirtd.h, src/conf/domain_conf.h, src/conf/interface_conf.h,
  src/conf/network_conf.h: Change bitfields to unsigned int.

Invoking the virConnectGetCapabilities() method causes the QEMU
driver to rebuild its internal capabilities object. Unfortunately
it was forgetting to register the custom domain status XML hooks
again.

To avoid this kind of error in the future, the code which builds
capabilities is refactored into one single method, which can be
called from all locations, ensuring reliable rebuilds.

* src/qemu/qemu_driver.c: Fix rebuilding of capabilities XML and
  guarentee it is always consistent

* src/util/logging.c (virLogMessage): Include "ignore-value.h".
Use it to ignore the return value of safewrite.
Use STDERR_FILENO, rather than "2".
* bootstrap (modules): Add ignore-value.
* gnulib: Update to latest, for ignore-value that is now LGPLv2+.

* src/xen/xen_driver.c (xenUnifiedDomainXMLFromNative): Also
free "conf" before returning.

This was accomplished in xml parsing by doing away with the
stripped-down virInterfaceBareDef object, and just always using
virInterfaceDef, but with restrictions in certain places (eg, the type
of subordinate interface allowed in parsing depends on the parent
interface).

xml formatting was similarly adjusted. In addition, the formatting
functions keep track of the level of interface nesting, and insert
extra leading spaces on each line accordingly (using %*s).

The only change in formatted xml from previous (aside frmo supporting
new combinations of interface types) is that the subordinate ethernet
interfaces take up 2 lines rather than one, eg:

   <interface type='ethernet' name='eth0'>
   </interface>

instead of:

   <interface type='ethernet' name='eth0'/>

* src/conf/storage_conf.c (virStoragePoolSourceListNewSource):
Free just-allocated "source" upon VIR_REALLOC_N failure.

I noticed some debug messages are printed with an empty lines after
them. This patch removes these empty lines from all invocations of the
following macros:
    VIR_DEBUG
    VIR_DEBUG0
    VIR_ERROR
    VIR_ERROR0
    VIR_INFO
    VIR_WARN
    VIR_WARN0
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

New pciDeviceIsAssignable() function for checking whether a given PCI
device can be assigned to a guest was added. Currently it only checks
for ACS being enabled on all PCIe switches between root and the PCI
device. In the future, it could be the right place to check whether a
device is unbound or bound to a stub driver.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Currently CPU topology may only be specified together with CPU model:
    <cpu match='exact'>
        <model>name</model>
        <topology sockets='1' cores='2' threads='3'/>
    </cpu>

This patch allows for CPU topology specification without the need for
also specifying CPU model:
    <cpu>
        <topology sockets='1' cores='2' threads='3'/>
    </cpu>

'match' attribute and 'model' element are made optional with the
restriction that 'match' attribute has to be set when 'model' is
present.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

When comparing incompatible CPUs, the reason for this incompatibility is
logged as a debug message.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

When comparing x86 CPUs, features with 'disabled' policy were mistakenly
required to be supported by the host CPU.

Likewise, features with 'force' policy which were supported by host CPU
would make CPUs incompatible if 'strict' match was used by guest CPU.

This patch fixes both issues.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

QEMU's command line equivalent for the following domain XML fragment
    <vcpus>2</vcpus>
    <cpu ...>
        ...
        <topology sockets='1' cores='2', threads='1'/>
    </cpu>

is

    -smp 2,sockets=1,cores=2,threads=1

This syntax was introduced in QEMU-0.12.

Version 2 changes:
- -smp argument build split into a separate function
- always add ",sockets=S,cores=C,threads=T" to -smp if qemu supports it
- use qemuParseCommandLineKeywords for command line parsing

Version 3 changes:
- ADD_ARG_LIT => ADD_ARG and line reordering in qemudBuildCommandLine
- rebased
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Current version expects name=value,... list and when an incorrect string
such as "a,b,c=d" would be parsed as "a,b,c" keyword with "d" value
without reporting any error, which is probably not the expected
behavior.

This patch adds an extra argument called allowEmptyValue, which if
non-zero will permit keywords with no value; "a,b=c,,d=" will be parsed
as follows:
    keyword value
    "a"     NULL
    "b"     "c"
    ""      NULL
    "d"     ""

In case allowEmptyValue is zero, the string is required to contain
name=value pairs only; retvalues is guaranteed to contain non-NULL
pointers. Now, "a,b,c=d" will result in an error.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

Replace

   -balloon virtio

With

   -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3

This allows it to get correct assigned PCI address as declared in
previous patch

 * src/qemu/qemu_conf.c: Convert Virtio ballon to -device and
   give it an explicit PCI address
 * tests/qemuxml2argvdata/qemuxml2argv-*args: Add in virtio balloon
   where appropriate

Instead of relying on QEMU to assign PCI addresses and then querying
them with 'info pci', manually assign all PCI addresses before starting
the guest.  These addresses are not stable across reboots. That will
come in a later patch

NB, the PIIX3 (IDE, FDC, ISA-Bridge) will always have slot 1 and
VGA will always have slot 2. We declare the Virtio Balloon gets
slot 3, and then all remaining slots are for configured devices.

* src/qemu/qemu_conf.c: If -device is supported, then assign all PCI
  addresses when building the command line
* src/qemu/qemu_driver.c: Don't query monitor for PCI addresses if
  they have already been assigned
* tests/qemuxml2argvdata/qemuxml2argv-hostdev-pci-address-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-net-virtio-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-sound-device.args,
  tests/qemuxml2argvdata/qemuxml2argv-watchdog-device.args: Update
  to include PCI slot/bus information

QEMU always configures a VGA card. If no video card is included in
the libvirt XML, it is neccessary to explicitly turn off the default
using -vga none

* src/qemu/qemu_conf.c: Pass -vga none if no video card is configured
* tests/qemuargv2xmltest.c, tests/qemuxml2argvtest.c: Test for
  handling -vga none.
* tests/qemuxml2argvdata/qemuxml2argv-nographics-vga.args,
  tests/qemuxml2argvdata/qemuxml2argv-nographics-vga.xml: Test
  data files

Not all QEMU builds default to SDL graphics for their display.
Newer QEMU now has an explicit -sdl flag, which we can use to
explicitly request SDL intead of relying on the default. This
protects libvirt against unexpected changes in graphics default

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Probe for -sdl
  flag and use it if it is found
* tests/qemuhelptest.c: Add SDL flag to tests

The old syntax was

   -chardev SOMECONFIG
   -nic user,guestfwd=tcp:IP:PORT-chardev:CHARDEV

The new syntax is

   -chardev SOMECONFIG
   -netdev user,guestfwd=tcp:IP:PORT,chardev=ID,id=user-ID

The old syntax is

  -pcidevice host=BUS:SLOT:FUNCTION

The new syntax is

  -device pci-assign,host=BUS:SLOT:FUNCTION,addr=<PCI SLOT>,id=host0