A bunch of code is wrapped in #if WITH_LIBVIRTD in order to
enable the virStateDriver to be disabled when libvirtd is not
built. Disabling this code doesn't have any real functional
benefit beyond removing 1 pointer from the virConnectPtr struct,
while having a cost of many more conditionals.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virTypedParameterValidateSet method will need to be used
from several libvirt-*.c files so must be non-static
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This patch adds some new RPC call numbers, but for ease of review,
they sit idle until a later patch adds the client counterpart to
drive the new RPCs.  Also for ease of review, I limited this patch
to just the lifecycle event; although converting the remaining
15 domain events will be quite mechanical.  On the server side,
we have to have a function per RPC call, largely with duplicated
bodies (the key difference being that we store in our callback
opaque pointer whether events should be fired with old or new
style); meanwhile, a single function can drive multiple RPC
messages.  With a strategic choice of XDR struct layout, we can
make the event generation code for both styles fairly compact.

I debated about adding a tri-state witness variable per
connection (values 'unknown', 'legacy', 'modern').  It would start
as 'unknown', move to 'legacy' if any RPC call is made to a legacy
event call, and move to 'modern' if the feature probe is made;
then the event code could issue an error if the witness state is
incorrect (a legacy RPC call while in 'modern', a modern RPC call
while in 'unknown' or 'legacy', and a feature probe while in
'legacy' or 'modern').  But while it might prevent odd behavior
caused by protocol fuzzing, I don't see that it would prevent
any security holes, so I considered it bloat.

Note that sticking @acl markers on the new RPCs generates unused
functions in access/viraccessapicheck.c, because there is no new
API call that needs to use the new checks; however, having a
consistent .x file is worth the dead code.

* src/libvirt_internal.h (VIR_DRV_FEATURE_REMOTE_EVENT_CALLBACK):
New feature.
* src/remote/remote_protocol.x
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_CALLBACK_REGISTER_ANY)
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_CALLBACK_DEREGISTER_ANY)
(REMOTE_PROC_DOMAIN_EVENT_CALLBACK_LIFECYCLE): New RPCs.
* daemon/remote.c (daemonClientCallback): Add field.
(remoteDispatchConnectDomainEventCallbackRegisterAny)
(remoteDispatchConnectDomainEventCallbackDeregisterAny): New
functions.
(remoteDispatchConnectDomainEventRegisterAny)
(remoteDispatchConnectDomainEventDeregisterAny): Mark legacy use.
(remoteRelayDomainEventLifecycle): Change message based on legacy
or new use.
(remoteDispatchConnectSupportsFeature): Advertise new feature.
* src/remote_protocol-structs: Regenerate.
Signed-off-by: NEric Blake <eblake@redhat.com>

This patch implements extensible variants of all internal migration APIs
used for v3 migration.

Building when configured --with-libvirtd=no fails with:

In file included from ../src/qemu/qemu_command.h:30:0,
                 from testutilsqemu.h:4,
                 from networkxml2xmltest.c:14:
../src/qemu/qemu_conf.h:175:5: error: expected specifier-qualifier-list before 'virStateInhibitCallback'

* src/libvirt_internal.h (virStateInhibitCallback): Move outside
of conditional.
Signed-off-by: NEric Blake <eblake@redhat.com>

Ensure that the driver struct field names match the public
API names. For an API virXXXX we must have a driver struct
field xXXXX. ie strip the leading 'vir' and lowercase any
leading uppercase letters.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Offline migration transfers inactive definition of a domain (which may
or may not be active). After successful completion, the domain remains
in its current state on source host and is defined but inactive on
destination host. It's a bit more clever than virDomainGetXMLDesc() on
source host followed by virDomainDefineXML() on destination host, as
offline migration will run pre-migration hook to update the domain XML
on destination host. Currently, copying non-shared storage is not
supported during offline migration.

Offline migration can be requested with a new migration flag called
VIR_MIGRATE_OFFLINE (which has to be combined with
VIR_MIGRATE_PERSIST_DEST flag).

Currently to deal with auto-shutdown libvirtd must periodically
poll all stateful drivers. Thus sucks because it requires
acquiring both the driver lock and locks on every single virtual
machine. Instead pass in a "inhibit" callback to virStateInitialize
which drivers can invoke whenever they want to inhibit shutdown
due to existance of active VMs.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virStateInitialize method and several cgroups methods were
using an 'int privileged' parameter or similar for dual-state
values. These are better represented with the bool type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

To allow actions to be performed in libvirtd when the host
shuts down, or user session exits, introduce a 'stop'
method to virDriverState. This will do things like saving
the VM state to a file.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

In v2 migration protocol, XML is obtained by calling domainGetXMLDesc.
This includes the default USB controller in XML, which breaks migration
to older libvirt (before 0.9.2).

Commit 409b5f54
    qemu: Emit compatible XML when migrating a domain
only fixed this for v3 migration.

This patch uses the new VIR_DOMAIN_XML_MIGRATABLE flag (detected by
VIR_DRV_FEATURE_XML_MIGRATABLE) to obtain XML without the default controller,
enabling backward v2 migration.

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/

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

virConnectSetKeepAlive public API can be used by a client connecting to
remote server to start using keepalive protocol. The API is handled
directly by remote driver and not transmitted over the wire to the
server.

This allows strings to be transported between client and server
in the context of name-type-value virTypedParameter functions.
For compatibility,

    o new clients will not send strings to old servers, based on
      a feature check
    o new servers will not send strings to old clients without the
      flag VIR_TYPED_PARAM_STRING_OKAY; this will be enforced at
      the RPC layer in the next patch, so that drivers need not
      worry about it in general.  The one exception is that
      virDomainGetSchedulerParameters lacks a flags argument, so
      it must not return a string; drivers that forward that
      function on to virDomainGetSchedulerParametersFlags will
      have to pay attention to the flag.
    o the flag VIR_TYPED_PARAM_STRING_OKAY is set automatically,
      based on a feature check (so far, no driver implements it),
      so clients do not have to worry about it

Future patches can then enable the feature on a per-driver basis.

This patch also ensures that drivers can blindly strdup() field
names (previously, a malicious client could stuff 80 non-NUL bytes
into field and cause a read overrun).

* src/libvirt_internal.h (VIR_DRV_FEATURE_TYPED_PARAM_STRING): New
driver feature.
* src/libvirt.c (virTypedParameterValidateSet)
(virTypedParameterSanitizeGet): New helper functions.
(virDomainSetMemoryParameters, virDomainSetBlkioParameters)
(virDomainSetSchedulerParameters)
(virDomainSetSchedulerParametersFlags)
(virDomainGetMemoryParameters, virDomainGetBlkioParameters)
(virDomainGetSchedulerParameters)
(virDomainGetSchedulerParametersFlags, virDomainBlockStatsFlags):
Use them.
* src/util/util.h (virTypedParameterArrayClear): New helper
function.
* src/util/util.c (virTypedParameterArrayClear): Implement it.
* src/libvirt_private.syms (util.h): Export it.
Based on an initial patch by Hu Tao, with feedback from
Daniel P. Berrange.
Signed-off-by: NEric Blake <eblake@redhat.com>

The virDomainOpenGraphics API allows a libvirt client to pass in
a file descriptor for an open socket pair, and get it connected
to the graphics display of the guest. This is limited to working
with local libvirt hypervisors connected over a UNIX domain
socket, since it will use UNIX FD passing

* include/libvirt/libvirt.h.in: Define virDomainOpenGraphics
* src/driver.h: Define driver for virDomainOpenGraphics
* src/libvirt_public.syms, src/libvirt.c: Entry point for
  virDomainOpenGraphics
* src/libvirt_internal.h: VIR_DRV_FEATURE_FD_PASSING

Make MIGRATION_OUT use the new helper methods.

This also introduces new protection to migration v3 process: the
migration job is held from Begin to Confirm to avoid changes to a domain
during migration (esp. between Begin and Perform phases). This change is
automatically applied to p2p and tunneled migrations. For normal
migration, this requires support from a client. In other words, if an
old (pre 0.9.4) client starts normal migration of a domain, the domain
will not be protected against changes between Begin and Perform steps.

The current virDomainMigrateFinish3 method signature attempts to
distinguish two types of errors, by allowing return with ret== 0,
but ddomain == NULL, to indicate a failure to start the guest.
This is flawed, because when ret == 0, there is no way for the
virErrorPtr details to be sent back to the client.

Change the signature of virDomainMigrateFinish3 so it simply
returns a virDomainPtr, in the same way as virDomainMigrateFinish2
The disk locking code will protect against the only possible
failure mode this doesn't account for (loosing conenctivity to
libvirtd after Finish3 starts the CPUs, but before the client
sees the reply for Finish3).

* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Change
  virDomainMigrateFinish3 to return a virDomainPtr instead of int
* src/remote/remote_driver.c, src/remote/remote_protocol.x,
  daemon/remote.c, src/qemu/qemu_driver.c, src/qemu/qemu_migration.c:
  Update for API change

The virDomainMigratePerform3 currently has a single URI parameter
whose meaning varies. It is either

 - A QEMU migration URI (normal migration)
 - A libvirtd connection URI (peer2peer migration)

Unfortunately when using peer2peer migration, without also
using tunnelled migration, it is possible that both URIs are
required.

This adds a second URI parameter to the virDomainMigratePerform3
method, to cope with this scenario. Each parameter how has a fixed
meaning.

NB, there is no way to actually take advantage of this yet,
since virDomainMigrate/virDomainMigrateToURI do not have any
way to provide the 2 separate URIs

* daemon/remote.c, src/remote/remote_driver.c,
  src/remote/remote_protocol.x, src/remote_protocol-structs: Add
  the second URI parameter to perform3 message
* src/driver.h, src/libvirt.c, src/libvirt_internal.h: Add
  the second URI parameter to Perform3 method
* src/libvirt_internal.h, src/qemu/qemu_migration.c,
  src/qemu/qemu_migration.h: Update to handle URIs correctly

This extends the v3 migration protocol such that the
virDomainMigrateBegin3 and virDomainMigratePerform3
methods accept an application supplied XML config for
the target VM.

If the 'xmlin' parameter is NULL, then Begin3 uses the
current guest XML as normal. A driver implementing the
Begin3 method should either reject all non-NULL 'xmlin'
parameters, or strictly validate that the app supplied
XML does not change guest ABI.

The Perform3 method also needed the xmlin parameter to
cope with the Peer2Peer migration sequence.

NB it is not yet possible to use this capability since
neither of the public virDomainMigrate/virDomainMigrateToURI
methods have a way to pass in XML.

* daemon/remote.c, src/remote/remote_driver.c,
  src/remote/remote_protocol.x, src/remote_protocol-structs:
  Add 'remote_string xmlin' parameter to begin3/perform3
  RPC messages
* src/libvirt.c, src/driver.h, src/libvirt_internal.h: Add
  'const char *xmlin' parameter to Begin3/Perform3 methods
* src/qemu/qemu_driver.c, src/qemu/qemu_migration.c,
  src/qemu/qemu_migration.h: Pass xmlin parameter around
  migration methods

Migration just seems to go from bad to worse. We already had to
introduce a second migration protocol when adding the QEMU driver,
since the one from Xen was insufficiently flexible to cope with
passing the data the QEMU driver required.

It turns out that this protocol still has some flaws that we
need to address. The current sequence is

 *  Src: DumpXML
          - Generate XML to pass to dst

 *  Dst: Prepare
          - Get ready to accept incoming VM
          - Generate optional cookie to pass to src

 *  Src: Perform
          - Start migration and wait for send completion
          - Kill off VM if successful, resume if failed

 *  Dst: Finish
          - Wait for recv completion and check status
          - Kill off VM if unsuccessful

The problems with this are:

 - Since the first step is a generic 'DumpXML' call, we can't
   add in other migration specific data. eg, we can't include
   any VM lease data from lock manager plugins
 - Since the first step is a generic 'DumpXML' call, we can't
   emit any 'migration begin' event on the source, or have
   any hook that runs right at the start of the process
 - Since there is no final step on the source, if the Finish
   method fails to receive all migration data & has to kill
   the VM, then there's no way to resume the original VM
   on the source

This patch attempts to introduce a version 3 that uses the
improved 5 step sequence

 *  Src: Begin
          - Generate XML to pass to dst
          - Generate optional cookie to pass to dst

 *  Dst: Prepare
          - Get ready to accept incoming VM
          - Generate optional cookie to pass to src

 *  Src: Perform
          - Start migration and wait for send completion
          - Generate optional cookie to pass to dst

 *  Dst: Finish
          - Wait for recv completion and check status
          - Kill off VM if failed, resume if success
          - Generate optional cookie to pass to src

 *  Src: Confirm
          - Kill off VM if success, resume if failed

The API is designed to allow both input and output cookies
in all methods where applicable. This lets us pass around
arbitrary extra driver specific data between src & dst during
migration. Combined with the extra 'Begin' method this lets
us pass lease information from source to dst at the start of
migration

Moving the killing of the source VM out of Perform and
into Confirm, means we can now recover if the dst host
can't successfully Finish receiving migration data.

* global: patch created by running:
for f in $(git ls-files '*.[ch]') ; do
    cppi $f > $f.t && mv $f.t $f
done

Introduces several new public API options for migration

 - VIR_MIGRATE_PEER2PEER: With this flag the client only
   invokes the virDomainMigratePerform method, expecting
   the source host driver to do whatever is required to
   complete the entire migration process.
 - VIR_MIGRATE_TUNNELLED: With this flag the actual data
   for migration will be tunnelled over the libvirtd RPC
   channel. This requires that VIR_MIGRATE_PEER2PEER is
   also set.
 - virDomainMigrateToURI: This is variant of the existing
   virDomainMigrate method which does not require any
   virConnectPtr for the destination host. Given suitable
   driver support, this allows for all the same modes as
   virDomainMigrate()

The URI for VIR_MIGRATE_PEER2PEER must be a valid libvirt
URI. For non-p2p migration a hypervisor specific migration
URI is used.

virDomainMigrateToURI without a PEER2PEER flag is only
support for Xen currently, and it involves XenD talking
directly to XenD, no libvirtd involved at all.

* include/libvirt/libvirt.h.in: Add VIR_MIGRATE_PEER2PEER
  flag for migration
* src/libvirt_internal.h: Add feature flags for peer to
  peer migration (VIR_FEATURE_MIGRATE_P2P) and direct
  migration (VIR_MIGRATE_PEER2PEER mode)
* src/libvirt.c: Implement support for VIR_MIGRATE_PEER2PEER
  and virDomainMigrateToURI APIs.
* src/xen/xen_driver.c: Advertise support for DIRECT migration
* src/xen/xend_internal.c: Add TODO item for p2p migration
* src/libvirt_public.syms: Export virDomainMigrateToURI
  method
* src/qemu/qemu_driver.c: Add support for PEER2PEER and
  migration, and adapt TUNNELLED migration.
* tools/virsh.c: Add --p2p and --direct args and use the
  new virDomainMigrateToURI method where possible.

Since virMigratePrepareTunnel() is used for migration over the
native libvirt connection, there is never any need to pass the
target URI to this method.

* daemon/remote.c, src/driver.h, src/libvirt.c, src/libvirt_internal.h,
  src/qemu/qemu_driver.c, src/remote/remote_driver.c,
  src/remote/remote_protocol.c, src/remote/remote_protocol.h,
  src/remote/remote_protocol.x: Remove 'uri_in' parameter from
  virMigratePrepareTunnel() method

Move the VIR_DRV_FEATURE* constants into libvirt_internal.h
since these flags are indicating whether  APIs in the
libvirt_internal.h file are supported by a driver

* src/driver.h: Remove VIR_DRV_FEATURE* constants
* src/libvirt_internal.h: Add VIR_DRV_FEATURE* constants, using
  an enum instead of #define
* src/internal.h: pull in libvirt_internal.h

Implementation of tunnelled migration, using a Unix Domain Socket
on the qemu backend.  Note that this requires very new versions of
qemu (0.10.7 at least) in order to get the appropriate bugfixes.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

Add a VIR_SECRET_GET_VALUE_INTERNAL_CALL flag value, replacing the
originally separate libvirt_internal_call parameter.  The flag is used
to differentiate external virSecretGetValue() calls from internal calls
by libvirt drivers that need to use the secret even if it is private.

* src/libvirt_internal.h Remove VIR_DOMAIN_XML_FLAGS_MASK
* src/driver.h Add VIR_SECRET_GET_VALUE_FLAGS_MASK constant and
  VIR_SECRET_GET_VALUE_INTERNAL_CALL. Re-add the
  VIR_DOMAIN_XML_FLAGS_MASK constant
* src/libvirt.c (virSecretGetValue): Don't allow the user to specify
  internal flags.

We need to store things like device names and PCI slot numbers in the
qemu domain state file so that we don't lose that information on
libvirtd restart. Add a flag to indicate that this information should
be parsed or formatted.

Make bit 16 and above of the flags bitmask for internal use only and
consume the first bit for this new status flag.

* include/libvirt/libvirt.h: add VIR_DOMAIN_XML_FLAGS_MASK

* src/libvirt.c: reject private flags in virDomainGetXMLDesc()

* src/domain_conf.h: add VIR_DOMAIN_XML_INTERNAL_STATUS

* src/domain_conf.c: pass the flag from virDomainObjParseXML() and
  virDomainSaveStatus

* qemud/remote.c qemud/remote_dispatch_localvars.h
  qemud/remote_dispatch_proc_switch.h qemud/remote_dispatch_prototypes.h
  qemud/remote_protocol.c qemud/remote_protocol.h
  qemud/remote_protocol.x src/driver.h src/libvirt.c
  src/libvirt_internal.h src/libvirt_sym.version src/lxc_driver.c
  src/openvz_driver.c src/qemu_conf.h src/qemu_driver.c
  src/remote_internal.c src/test.c src/virsh.c: large patch to
  add migration support for KVM/QEmu, based on the work of Rich Jones
  and Chris Lalancette. This introduce a new version of the prepare
  and finish steps of the migration, so changes the driver API and
  a lot of code.
Daniel