Expand the "secmodel" XML fragment of "host" with a sequence of
baselabel's which describe the default security context used by
libvirt with a specific security model and virtualization type:

<secmodel>
  <model>selinux</model>
  <doi>0</doi>
  <baselabel type='kvm'>system_u:system_r:svirt_t:s0</baselabel>
  <baselabel type='qemu'>system_u:system_r:svirt_tcg_t:s0</baselabel>
</secmodel>
<secmodel>
  <model>dac</model>
  <doi>0</doi>
  <baselabel type='kvm'>107:107</baselabel>
  <baselabel type='qemu'>107:107</baselabel>
</secmodel>

"baselabel" is driver-specific information, e.g. in the DAC security
model, it indicates USER_ID:GROUP_ID.
Signed-off-by: NGiuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

There are still two places where we are using 1bit width unsigned
integer to store a boolean. There's no real need for this and these
occurrences can be replaced with 'bool'.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Some ancient gcc fails to see the variables are initialized in a
separate function and a false positive is produced:

cc1: warnings being treated as errors
conf/domain_conf.c: In function 'virDomainChrGetDomainPtrs':
conf/domain_conf.c:10342: error: 'arrVar' may be used uninitialized in this function [-Wuninitialized]
conf/domain_conf.c:10343: error: 'cntVar' may be used uninitialized in this function [-Wuninitialized]
conf/domain_conf.c: In function 'virDomainChrInsert':
conf/domain_conf.c:10362: error: 'arrPtr' may be used uninitialized in this function [-Wuninitialized]
conf/domain_conf.c:10363: error: 'cntPtr' may be used uninitialized in this function [-Wuninitialized]
conf/domain_conf.c: In function 'virDomainChrRemove':
conf/domain_conf.c:10374: error: 'arrPtr' may be used uninitialized in this function [-Wuninitialized]
conf/domain_conf.c:10375: error: 'cntPtr' may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Use apostrophes to denote user provided option names when parsing the
domain XML.

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up remaining offenders in src/conf, and their fallout.

* src/conf/snapshot_conf.h (virDomainSnapshotAssignDef)
(virDomainSnapshotFindByName): Drop attempt at const.
* src/conf/interface_conf.h (virInterfaceObjIsActive)
(virInterfaceDefFormat): Use intended type.
(virInterfaceFindByMACString, virInterfaceFindByName)
(virInterfaceAssignDef, virInterfaceRemove): Drop attempt at
const.
* src/conf/network_conf.h (virNetworkObjIsActive)
(virNetworkDefFormat, virNetworkDefForwardIf)
(virNetworkDefGetIpByIndex, virNetworkIpDefPrefix)
(virNetworkIpDefNetmask): Use intended type.
(virNetworkFindByUUID, virNetworkFindByName, virNetworkAssignDef)
(virNetworkObjAssignDef, virNetworkRemoveInactive)
(virNetworkBridgeInUse, virNetworkSetBridgeName)
(virNetworkAllocateBridge): Drop attempt at const.
* src/conf/netdev_vlan_conf.h (virNetDevVlanFormat): Make
const-correct.
* src/conf/node_device_conf.h (virNodeDeviceHasCap)
(virNodeDeviceDefFormat): Use intended type.
(virNodeDeviceFindByName, virNodeDeviceFindBySysfsPath)
(virNodeDeviceAssignDef, virNodeDeviceObjRemove)
(virNodeDeviceGetParentHost): Drop attempt at const.
* src/conf/secret_conf.h (virSecretDefFormat): Use intended type.
* src/conf/snapshot_conf.c (virDomainSnapshotAssignDef)
(virDomainSnapshotFindByName): Fix fallout.
* src/conf/interface_conf.c (virInterfaceBridgeDefFormat)
(virInterfaceBondDefFormat, virInterfaceVlanDefFormat)
(virInterfaceProtocolDefFormat, virInterfaceDefDevFormat)
(virInterfaceDefFormat, virInterfaceFindByMACString)
(virInterfaceFindByName, virInterfaceAssignDef)
(virInterfaceRemove): Likewise.
* src/conf/network_conf.c
(VIR_ENUM_IMPL, virNetworkFindByName, virNetworkObjAssignDef)
(virNetworkAssignDef, virNetworkRemoveInactive)
(virNetworkDefGetIpByIndex, virNetworkIpDefPrefix)
(virNetworkIpDefNetmask, virNetworkDHCPHostDefParseXML)
(virNetworkIpDefFormat, virNetworkRouteDefFormat)
(virPortGroupDefFormat, virNetworkForwardNatDefFormat)
(virNetworkDefFormatInternal, virNetworkBridgeInUse)
(virNetworkAllocateBridge, virNetworkSetBridgeName)
(virNetworkDNSDefFormat, virNetworkDefFormat): Likewise.
* src/conf/netdev_vlan_conf.c (virNetDevVlanFormat): Likewise.
* src/conf/node_device_conf.c (virNodeDeviceHasCap)
(virNodeDeviceFindBySysfsPath, virNodeDeviceFindByName)
(virNodeDeviceAssignDef, virNodeDeviceObjRemove)
(virNodeDeviceDefFormat, virNodeDeviceGetParentHost): Likewise.
* src/conf/secret_conf.c (virSecretDefFormatUsage)
(virSecretDefFormat): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up offenders in src/conf/domain_conf, and their fallout.

Several things to note: virObjectLock() requires a non-const
argument; if this were C++, we could treat the locking field
as 'mutable' and allow locking an otherwise 'const' object, but
that is a more invasive change, so I instead dropped attempts
to be const-correct on domain lookup.  virXMLPropString and
friends require a non-const xmlNodePtr - this is because libxml2
is not a const-correct library.  We could make the src/util/virxml
wrappers cast away const, but I figured it was easier to not
try to mark xmlNodePtr as const.  Finally, virDomainDeviceDefCopy
was a rather hard conversion - it calls virDomainDeviceDefPostParse,
which in turn in the xen driver was actually modifying the domain
outside of the current device being visited.  We should not be
adding a device on the first per-device callback, but waiting until
after all per-device callbacks are complete.

* src/conf/domain_conf.h (virDomainObjListFindByID)
(virDomainObjListFindByUUID, virDomainObjListFindByName)
(virDomainObjAssignDef, virDomainObjListAdd): Drop attempt at
const.
(virDomainDeviceDefCopy): Use intended type.
(virDomainDeviceDefParse, virDomainDeviceDefPostParseCallback)
(virDomainVideoDefaultType, virDomainVideoDefaultRAM)
(virDomainChrGetDomainPtrs): Make const-correct.
* src/conf/domain_conf.c (virDomainObjListFindByID)
(virDomainObjListFindByUUID, virDomainObjListFindByName)
(virDomainDeviceDefCopy, virDomainObjListAdd)
(virDomainObjAssignDef, virDomainHostdevSubsysUsbDefParseXML)
(virDomainHostdevSubsysPciOrigStatesDefParseXML)
(virDomainHostdevSubsysPciDefParseXML)
(virDomainHostdevSubsysScsiDefParseXML)
(virDomainControllerModelTypeFromString)
(virDomainTPMDefParseXML, virDomainTimerDefParseXML)
(virDomainSoundCodecDefParseXML, virDomainSoundDefParseXML)
(virDomainWatchdogDefParseXML, virDomainRNGDefParseXML)
(virDomainMemballoonDefParseXML, virDomainNVRAMDefParseXML)
(virSysinfoParseXML, virDomainVideoAccelDefParseXML)
(virDomainVideoDefParseXML, virDomainHostdevDefParseXML)
(virDomainRedirdevDefParseXML)
(virDomainRedirFilterUsbDevDefParseXML)
(virDomainRedirFilterDefParseXML, virDomainIdMapEntrySort)
(virDomainIdmapDefParseXML, virDomainVcpuPinDefParseXML)
(virDiskNameToBusDeviceIndex, virDomainDeviceDefCopy)
(virDomainVideoDefaultType, virDomainHostdevAssignAddress)
(virDomainDeviceDefPostParseInternal, virDomainDeviceDefPostParse)
(virDomainChrGetDomainPtrs, virDomainControllerSCSINextUnit)
(virDomainSCSIDriveAddressIsUsed)
(virDomainDriveAddressIsUsedByDisk)
(virDomainDriveAddressIsUsedByHostdev): Fix fallout.
* src/openvz/openvz_driver.c (openvzDomainDeviceDefPostParse):
Likewise.
* src/libxl/libxl_domain.c (libxlDomainDeviceDefPostParse):
Likewise.
* src/qemu/qemu_domain.c (qemuDomainDeviceDefPostParse)
(qemuDomainDefaultNetModel): Likewise.
* src/lxc/lxc_domain.c (virLXCDomainDeviceDefPostParse):
Likewise.
* src/uml/uml_driver.c (umlDomainDeviceDefPostParse): Likewise.
* src/xen/xen_driver.c (xenDomainDeviceDefPostParse): Split...
(xenDomainDefPostParse): ...since per-device callback is not the
time to be adding a device.
Signed-off-by: NEric Blake <eblake@redhat.com>

virDomainChrGetDomainPtrs() required 4 levels of pointers (taking
a parameter that will be used as an output variable to return the
address of another variable that contains an array of pointers).
This is rather complex to reason about, especially when outside
of the domain_conf file, no other caller should be modifying
the resulting array of pointers directly.  Changing the public
signature gives something is easier to reason with, and actually
make const-correct; which is important as it was the only function
that was blocking virDomainDeviceDefCopy from treating its source
as const.

* src/conf/domain_conf.h (virDomainChrGetDomainPtrs): Use simpler
types, and make const-correct for external users.
* src/conf/domain_conf.c (virDomainChrGetDomainPtrs): Split...
(virDomainChrGetDomainPtrsInternal): ...into an internal version
that lets us modify terms, vs. external form that is read-only.
(virDomainDeviceDefPostParseInternal, virDomainChrFind)
(virDomainChrInsert): Adjust callers.
* src/qemu/qemu_command.c (qemuGetNextChrDevIndex): Adjust caller.
(qemuDomainDeviceAliasIndex): Make const-correct.
Signed-off-by: NEric Blake <eblake@redhat.com>

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up offenders in nwfilter code.

This patch does nothing about the stupidity evident in having
__virNWFilterInstantiateFilter, _virNWFilterInstantiateFilter,
and virNWFilterInstantiateFilter, which differ only by leading
underscores, and which infringes on the namespace reserved to
the implementation - that would need to be a separate cleanup.

* src/nwfilter/nwfilter_dhcpsnoop.h (virNWFilterDHCPSnoopReq): Use
intended type.
* src/nwfilter/nwfilter_gentech_driver.h
(virNWFilterInstantiateFilter)
(virNWFilterUpdateInstantiateFilter)
(virNWFilterInstantiataeFilterLate, virNWFilterTeardownFilter)
(virNWFilterCreateVarHashmap): Likewise.
* src/nwfilter/nwfilter_learnipaddr.h (virNWFilterLearnIPAddress):
Likewise.
* src/conf/nwfilter_conf.h (virNWFilterApplyBasicRules)
(virNWFilterApplyDHCPOnlyRules): Likewise.
(virNWFilterDefFormat): Make const-correct.
* src/conf/nwfilter_params.h (virNWFilterVarValueCopy)
(virNWFilterVarValueGetSimple, virNWFilterVarValueGetCardinality)
(virNWFilterVarValueEqual, virNWFilterVarAccessEqual)
(virNWFilterVarAccessGetVarName, virNWFilterVarAccessGetType)
(virNWFilterVarAccessGetIterId, virNWFilterVarAccessGetIndex)
(virNWFilterVarAccessIsAvailable)
(virNWFilterVarCombIterGetVarValue): Use intended type.
(virNWFilterVarValueGetNthValue): Make const-correct.
* src/nwfilter/nwfilter_dhcpsnoop.c (virNWFilterSnoopReqLeaseDel)
(virNWFilterSnoopIFKeyFMT, virNWFilterDHCPSnoopReq)
(virNWFilterSnoopPruneIter, virNWFilterSnoopRemAllReqIter)
(virNWFilterDHCPSnoopReq): Fix fallout.
* src/nwfilter/nwfilter_gentech_driver.c
(virNWFilterVarHashmapAddStdValues, virNWFilterCreateVarHashmap)
(virNWFilterInstantiate, __virNWFilterInstantiateFilter)
(_virNWFilterInstantiateFilter, virNWFilterInstantiateFilterLate)
(virNWFilterInstantiateFilter)
(virNWFilterUpdateInstantiateFilter)
(virNWFilterRollbackUpdateFilter, virNWFilterTeardownFilter):
Likewise.
* src/nwfilter/nwfilter_learnipaddr.c (virNWFilterLearnIPAddress):
Likewise.
* src/conf/nwfilter_params.c (virNWFilterVarValueCopy)
(virNWFilterVarValueGetSimple)
(virNWFilterVarValueGetCardinality, virNWFilterVarValueEqual)
(virNWFilterVarCombIterAddVariable)
(virNWFilterVarCombIterGetVarValue, virNWFilterVarValueCompare)
(virNWFilterFormatParamAttributes, virNWFilterVarAccessEqual)
(virNWFilterVarAccessGetVarName, virNWFilterVarAccessGetType)
(virNWFilterVarAccessGetIterId, virNWFilterVarAccessGetIndex)
(virNWFilterVarAccessGetIntIterId)
(virNWFilterVarAccessIsAvailable)
(virNWFilterVarValueGetNthValue): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c (ebtablesApplyBasicRules)
(ebtablesApplyDHCPOnlyRules, ebiptablesRuleOrderSort)
(ebiptablesRuleOrderSortPtr): Likewise.
* src/conf/nwfilter_conf.c (virNWFilterDefEqual)
(virNWFilterDefFormat): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up offenders in src/cpu.

* src/cpu/cpu.h (cpuArchDecode, cpuArchEncode, cpuArchUpdate)
(cpuArchHasFeature, cpuDecode, cpuEncode, cpuUpdate)
(cpuHasFeature): Use intended type.
* src/conf/cpu_conf.h (virCPUDefCopyModel, virCPUDefCopy):
Likewise.
(virCPUDefParseXML): Drop const.
* src/cpu/cpu.c (cpuDecode, cpuEncode, cpuUpdate, cpuHasFeature):
Fix fallout.
* src/cpu/cpu_x86.c (x86ModelFromCPU, x86ModelSubtractCPU)
(x86DecodeCPUData, x86EncodePolicy, x86Encode, x86UpdateCustom)
(x86UpdateHostModel, x86Update, x86HasFeature): Likewise.
* src/cpu/cpu_s390.c (s390Decode): Likewise.
* src/cpu/cpu_arm.c (ArmDecode): Likewise.
* src/cpu/cpu_powerpc.c (ppcModelFromCPU, ppcCompute, ppcDecode)
(ppcUpdate): Likewise.
* src/conf/cpu_conf.c (virCPUDefCopyModel, virCPUDefCopy)
(virCPUDefParseXML): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up virhash to provide a const-correct interface: all actions
that don't modify the table take a const table.  Note that in
one case (virHashSearch), we actually strip const away - we aren't
modifying the contents of the table, so much as associated data
for ensuring that the code uses the table correctly (if this were
C++, it would be a case for the 'mutable' keyword).

* src/util/virhash.h (virHashKeyComparator, virHashEqual): Use
intended type.
(virHashSize, virHashTableSize, virHashLookup, virHashSearch):
Make const-correct.
* src/util/virhash.c (virHashEqualData, virHashEqual)
(virHashLookup, virHashSize, virHashTableSize, virHashSearch)
(virHashComputeKey): Fix fallout.
* src/conf/nwfilter_params.c
(virNWFilterFormatParameterNameSorter): Likewise.
* src/nwfilter/nwfilter_ebiptables_driver.c
(ebiptablesFilterOrderSort): Likewise.
* tests/virhashtest.c (testHashGetItemsCompKey)
(testHashGetItemsCompValue): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

The enum for virNetDevVPort is declared in the header file
virnetdevvportprofile.h, but for some reason the impl is
in netdev_vport_profile_conf.c.

This causes a dep from src/util onto src/conf which is not
allowed. Move the enum impl into virnetdevvportprofile.c
to break the circle.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Prefer using VFIO (if available) to the legacy KVM device passthrough.

With this patch a PCI passthrough device without the driver configured
will be started with VFIO if it's available on the host. If not legacy
KVM passthrough is checked and error is reported if it's not available.

Since 76b644c3 when the support for RAM filesystems was introduced,
libvirt accepted the following XML:
<source usage='1024' unit='KiB'/>

This was parsed correctly and internally stored in bytes, but it
was formatted as (with an extra 's'):
<source usage='1024' units='KiB'/>
When read again, this was treated as if the units were missing,
meaning libvirt was unable to parse its own XML correctly.

The usage attribute was documented as being in KiB, but it was not
scaled if the unit was missing. Transient domains still worked,
because this was balanced by an extra 'k' in the mount options.

This patch:
Changes the parser to use 'units' instead of 'unit', as the latter
was never documented (fixing persistent domains) and some programs
(libvirt-glib, libvirt-sandbox) already parse the 'units' attribute.

Removes the extra 'k' from the tmpfs mount options, which is needed
because now we parse our own XML correctly.

Changes the default input unit to KiB to match documentation, fixing:
https://bugzilla.redhat.com/show_bug.cgi?id=1015689

The virConnectPtr is passed around loads of nwfilter code in
order to provide it as a parameter to the callback registered
by the virt drivers. None of the virt drivers use this param
though, so it serves no purpose.

Avoiding the need to pass a virConnectPtr means that the
nwfilterStateReload method no longer needs to open a bogus
QEMU driver connection. This addresses a race condition that
can lead to a crash on startup.

The nwfilter driver starts before the QEMU driver and registers
some callbacks with DBus to detect firewalld reload. If the
firewalld reload happens while the QEMU driver is still starting
up though, the nwfilterStateReload method will open a connection
to the partially initialized QEMU driver and cause a crash.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The nwfilter driver only needs a reference to its private
state object, not a full virConnectPtr. Update the domUpdateCBStruct
struct to have a 'void *opaque' field instead of a virConnectPtr.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

None of the virNWFilterDefParse* methods require a virConnectPtr
arg, so just drop it
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Again stolen from qemu_driver.c, but dropping all the unneeded bits.
This aims to copy all the current qemu validation checks since that's
the most commonly used real driver, but some of the checks are
completely artificial in the test driver.

This only supports creation of internal snapshots for initial
simplicity.

Tweak some conditions and use correct typecasts in enums.

Since commit 297c99a5 an invalid source definition XML of a character
device that is used as backend for RNG devices, smartcards and redirdevs
causes crash of the daemon when parsing such a definition.

The device types mentioned above are not a part of a regular character
device but are backends for other types. Thus when parsing such device
NULL is passed as the argument @chr_def. Later when checking the
validity of the definition @chr_def was dereferenced when parsing a UNIX
socket backend with missing path of the socket and crashed the daemon.

Sample offending configuration:
  <devices>
  ...
    <rng model='virtio'>
      <backend model='egd' type='unix'>
        <source mode='bind' service='1024'/>
      </backend>
    </rng>
  </devices>

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1012196

For inexplicable reasons, the nwfilter XML parser is intentionally
ignoring errors that arise during parsing. As well as meaning that
users don't get any feedback on their XML mistakes, this will lead
it to silently drop data in OOM conditions.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virStoragePoolDefParseSource method would set def->nhosts
before allocating def->hosts. If the allocation failed due to
OOM, the cleanup code would crash accessing out of bounds.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virDomainSnapshotDefParse method assigned to def->ndisks
before allocating def->disks. Thus if an OOM occurred, the
cleanup code would access out of bounds.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Several places in virInterfaceDefParseProtoIPv6 clobber the
default 'ret' return value. So when jumping to cleanup on
error, 'ret' may mistakenly be set to 0 instead of -1. This
caused failure to report OOM errors, meaning data was silently
lost during parsing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If virBitmapNew fails due to OOM, the 'vcpupin' variable
is leaked.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If the virBitmapParse method fails due to OOM, we leak
the 'tmp' variable string.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If virDomainSoundCodecDefParseXML returns an error (eg due
to OOM), then the xml nodeset codecNodes is leaked.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If virDomainVcpuPinDefArrayFree is called with def != NULL,
but nvcpupin == 0, then it leaks memory for 'def'. This is
an unusual scenario, but it hits when cleaning up after an
OOM during parsing of XML.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This resolves one of the issues in:

   https://bugzilla.redhat.com/show_bug.cgi?id=1003983

This device is identical to qemu's "intel-hda" device (known as "ich6"
in libvirt), but has a different PCI device ID (which matches the ID
of the hda audio built into the ich9 chipset, of course). It's not
supported in earlier versions of qemu, so it requires a capability
bit.

The parsing of '-usb' did not check for failure of the
virDomainControllerInsert method. As a result on OOM, the
parser mistakenly attached USB disks to the IDE controller.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virDomainDefParseXML method did not check the return value
of the virBitmapNew API call for NULL. This lead to a crash on
OOM
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If an OOM error occurs in virSecurityDeviceLabelDefParseXML the
cleanup code may free an uninitialized pointer, causing a crash
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The ABI compatibility check for domain features didn't check the
expanded HyperV and APIC EOI values, thus possibly allowing change in
guest ABI.

Add the check and use typecasted switch statement to warn developers
when adding a new HyperV feature.

Useful to set custom forwarders instead of using the contents of
/etc/resolv.conf. It helps me to setup dnsmasq as local nameserver to
resolve VM domain names from domain 0, when domain option is used.
Signed-off-by: NDiego Woitasen <diego.woitasen@vhgroup.net>
Signed-off-by: NEric Blake <eblake@redhat.com>

Currently the XML parser already allows the following syntax:
  <disk type='block' device='cdrom'>
    <source startupPolicy='optional'/>
    <target dev='hda' bus='ide'/>
    <address type='drive' controller='0' bus='0' target='0' unit='0'/>
  </disk>

But it if the dev value is NULL then it would not have the leading
"<source ", resulting in invalid XML.

qemu/KVM also supports a tftp URL while specifying the cdrom ISO image.

The xml should be as following:

    <disk type='network' device='cdrom'>
      <source protocol='tftp' name='/url/path'>
        <host name='host.name' port='69'/>
      </source>
    </disk>
Signed-off-by: NAline Manera <alinefm@br.ibm.com>

The ftps protocol is another protocol supported by qemu/KVM while specifying
the cdrom ISO image.

The xml should be as following:

    <disk type='network' device='cdrom'>
      <source protocol='ftps' name='/url/path'>
        <host name='host.name' port='990'/>
      </source>
    </disk>
Signed-off-by: NAline Manera <alinefm@br.ibm.com>

The https protocol is also accepted by qemu/KVM when specifying the cdrom ISO
image.

The xml should be as following:

    <disk type='network' device='cdrom'>
      <source protocol='https' name='/url/path'>
        <host name='host.name' port='443'/>
      </source>
    </disk>
Signed-off-by: NAline Manera <alinefm@br.ibm.com>

GCC 4.8.0+ whines about variable "new" being uninitialized since
commit 73bfac0e. This is a false positive as the
xmlFreeNode(new) statement can be only reached if new was actually
allocated successfully.

  CC       conf/libvirt_conf_la-domain_conf.lo
  conf/domain_conf.c: In function 'virDomainDefSetMetadata':
  conf/domain_conf.c:18650:24: error: 'new' may be used uninitialized in this function [-Werror=maybe-uninitialized]
               xmlFreeNode(new);

Reported independently by John Ferlan and Michal Privoznik.