Storage drivers now don't allow it so there's no need to test it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The second set of arguments for TEST_CHAIN always specifies the
'ALLOW_PROBE' flag. Make it part of the macro.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We have a test case for QED disk image with autodetection but not with
the format explicitly specified.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
As the aa-helper binary is supposed to be used only with libvirt, we can
fully remove it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Nothing is setting that flag now so it can be removed. Note that
removing 'mgr' from 'load_profile' in the apparmor driver would create a
lot of churn.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Previous patch naively removed all code relevant to disk format
checking. The semantics now dictate that the format check when creating
external snapshots is now impossible as we always fill in the format for
disks in domain definition in the post-parse callback.
Remove the impossible code path.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The option is insecure and it has been long enough for users to migrate
their disk files to use explicit format. Drop the option and related
code.
The config parser still parses it and rejects statup if it's still
present in the config in enabled state.
The augeas lens is also kept so that users can disable it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Format probing will be dropped so remove the tests which will become
obsolete.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The compilation fails with the following error when pcap-config
is not present on the host:
nwfilter/nwfilter_learnipaddr.c:824:1: error: conflicting types for 'virNWFilterLearnIPAddress'
virNWFilterLearnIPAddress(virNWFilterTechDriverPtr techdriver ATTRIBUTE_UNUSED,
In file included from nwfilter/nwfilter_learnipaddr.c:57:0:
nwfilter/nwfilter_learnipaddr.h:38:5: note: previous declaration of 'virNWFilterLearnIPAddress' was here
int virNWFilterLearnIPAddress(virNWFilterTechDriverPtr techdriver,
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
When a QEMU VM shuts down its TAP device gets deleted while nwfilter
IP address learning thread is still capturing packets. It is seen that
with TPACKET_V3 support in libcap, the pcap_next() call will not always
exit its poll() when the NIC is removed. This prevents the learning
thread from exiting which blocks the rest of libvirtd waiting on mutex
acquisition. By switching to do poll() in libvirt code, we can ensure
that we always exit the poll() at a time that is right for libvirt.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In a previous commit:
commit d4bf8f4150
Author: Daniel P. Berrangé <berrange@redhat.com>
Date: Wed Feb 14 09:43:59 2018 +0000
nwfilter: handle missing switch enum cases
Ensure all enum cases are listed in switch statements, or cast away
enum type in places where we don't wish to cover all cases.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
we changed a switch in the nwfilter learning thread so that it had
explict cases for all enum entries. Unfortunately the parameters in the
method had been declared with incorrect type. The "howDetect" parameter
does *not* accept "enum howDetect" values, rather it accepts a bitmask
of "enum howDetect" values, so it should have been an "int" type.
The caller always passes DETECT_STATIC|DETECT_DHCP, so essentially the
IP addressing learning was completely broken by the above change, as it
never matched any switch case, hitting the default leading to EINVAL.
Stop using a typedef for the parameter name this this is a bitmask,
not a plain enum value. Also stop using switch() since that's misleading
with bitmasks too.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The process used to build the snapshots no longer works because the box
it runs on is outdated. Analysing the web logs shows the majority of
traffic to these links is from search engine bots. With those removed,
there is about 1 hit per day from (probable) humans.
Most users needing a tarball are better served by using official
releases. Those needing latest code are better served by using git
checkout. The tarball snapshots are not compelling enough to invest time
in fixing the script that produces them.
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Recently, bhyve started supporting specifying guest CPU topology.
It looks this way:
bhyve -c cpus=C,sockets=S,cores=C,threads=T ...
The old behaviour was bhyve -c C, where C is a number of vCPUs, is
still supported.
So if we have CPU topology in the domain XML, use the new syntax,
otherwise keep the old behaviour.
Also, document this feature in the bhyve driver page.
Signed-off-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Currently there's a function called bhyveProbeCapsRTC_UTC() that
parses bhyve capabilities from the bhyve help output (bhyve -h).
Right now it only checks the '-u' flag, but as there will be more
features detectable through this help output, give it more general
name: bhyveProbeCapsFromHelp().
Signed-off-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The container images provided by Travis only support Ubuntu 14.04,
however, Travis has ability to run docker, which allows the build
script to use arbitrary OS images. This takes advantage of that to
convert the build over to Ubuntu 16.04 and 18.04
This is using the official Ubuntu provided images and installing
extra build deps required, as we previously did with Travis container
images.
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The default is actually `on` when `<smm/>` is specified.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Amend the paragraphs about no CLAs and implicit license
agreements to mention mandatory Signed-off-by tags.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
qemu_tpm.c is not calling any capng_* functions. Let's drop this
include then. This also fixes a build failure without capng.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1529059
Commit id 0fe4aa14 added the thread specific error message
reporting (or save) to virFDStreamEvent; however, as processing
goes via virStream{Send|SendHole|Recv} via calls from
daemonStreamHandle{WriteData|Hole|Read} the last error
gets reset in the main libvirt API's thus, whatever error
may have been set as last error will be cleared prior to
the error paths using it resulting in the generic error
on the client side.
For each of the paths that check threadQuit or threadErr,
check if threadErr was set and set it agian if there isn't
a last error (e.g. some other failure) set so that the
message can be provided back to the client.
Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Michal Privoznik <mprivozn@redhat.com>
The dirent's d_type field is not portable to all platforms. So we have
to use stat() to determine the type of file for the functions that need
to be cross-platform. Fix virFileChownFiles() by calling the new
virFileIsRegular() function.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
When using an enum in a struct field, the compiler is free to decide to
make it an unsigned type if it desires. This in turn leads to bugs when
code does
if ((def->foo = virDomainFooTypeFromString(str)) < 0)
...
because 'def->foo' can't technically have an unsigned value from the
compiler's POV. While it is possible to add (int) casts in the code
example above, this is not desirable because it is easy to miss out
such casts. eg the code fixed here caused an error with clang builds
../../src/conf/domain_conf.c:12838:73: error: comparison of unsigned enum expression < 0 is always false [-Werror,-Wtautological-compare]
if ((def->version = virDomainTPMVersionTypeFromString(version)) < 0) {
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ^ ~
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Fix the case when creating a luks encrypted volume
via an xml file without 'secret' element.
libvirtd was receiving SIGSEGV, now proper error is reported for
the missing element.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1468422
Signed-off-by: Katerina Koukiou <kkoukiou@redhat.com>
Fix the resrc field for the TPM passthrough case to show tpm.
This fixes the code to follow the documentation.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend the existing auditing with auditing for the TPM emulator.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
swtpm_setup can be run for a TPM 2 in unprivileged mode assuming
XDG_CONFIG_HOME has been set and the necessary configuration files
have been put into that directory.
For current reference also see this link:
https://github.com/stefanberger/swtpm/pull/63
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Add the external swtpm to the emulator cgroup so that upper limits of CPU
usage can be enforced on the emulated TPM.
To enable this we need to have the swtpm write its process id (pid) into a
file. We then read it from the file to configure the emulator cgroup.
The PID file is created in /var/run/libvirt/qemu/swtpm:
[root@localhost swtpm]# ls -lZ /var/run/libvirt/qemu/swtpm/
total 4
-rw-r--r--. 1 tss tss system_u:object_r:qemu_var_run_t:s0 5 Apr 10 12:26 1-testvm-swtpm.pid
srw-rw----. 1 qemu qemu system_u:object_r:svirt_image_t:s0:c597,c632 0 Apr 10 12:26 1-testvm-swtpm.sock
The swtpm command line now looks as follows:
root@localhost testvm]# ps auxZ | grep swtpm | grep socket | grep -v grep
system_u:system_r:virtd_t:s0:c597,c632 tss 18697 0.0 0.0 28172 3892 ? Ss 16:46 0:00 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/1-testvm-swtpm.sock,mode=0600 --tpmstate dir=/var/lib/libvirt/swtpm/485d0004-a48f-436a-8457-8a3b73e28568/tpm1.2/ --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log --pid file=/var/run/libvirt/qemu/swtpm/1-testvm-swtpm.pid
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch extends the TPM's device XML with TPM 2.0 support. This only works
for the emulator type backend and looks as follows:
<tpm model='tpm-tis'>
<backend type='emulator' version='2.0'/>
</tpm>
The swtpm process now has --tpm2 as an additional parameter:
system_u:system_r:svirt_t:s0:c597,c632 tss 18477 11.8 0.0 28364 3868 ? Rs 11:13 13:50 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/testvm-swtpm.sock,mode=0660 --tpmstate dir=/var/lib/libvirt/swtpm/testvm/tpm2,mode=0640 --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log --tpm2 --pid file=/var/run/libvirt/qemu/swtpm/testvm-swtpm.pid
The version of the TPM can be changed and the state of the TPM is preserved.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
In this patch we label the swtpm process with SELinux labels. We give it the
same label as the QEMU process has. We label its state directory and files
as well. We restore the old security labels once the swtpm has terminated.
The file and process labels now look as follows:
Directory: /var/lib/libvirt/swtpm
[root@localhost swtpm]# ls -lZ
total 4
rwx------. 2 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 4096 Apr 5 16:46 testvm
[root@localhost testvm]# ls -lZ
total 8
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 3648 Apr 5 16:46 tpm-00.permall
The log in /var/log/swtpm/libvirt/qemu is labeled as follows:
-rw-r--r--. 1 tss tss system_u:object_r:svirt_image_t:s0:c254,c932 2237 Apr 5 16:46 vtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep swtpm | grep ctrl | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 tss 25664 0.0 0.0 28172 3892 ? Ss 16:57 0:00 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/testvm-swtpm.sock,mode=0660 --tpmstate dir=/var/lib/libvirt/swtpm/testvm/tpm1.2 --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep qemu | grep tpm | grep -v grep
system_u:system_r:svirt_t:s0:c254,c932 qemu 25669 99.0 0.0 3096704 48500 ? Sl 16:57 3:28 /bin/qemu-system-x86_64 [..]
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch adds extensions to existing test cases and specific test cases
for the tpm-emulator.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch adds support for an external swtpm TPM emulator. The XML for
this type of TPM looks as follows:
<tpm model='tpm-tis'>
<backend type='emulator'/>
</tpm>
The XML will currently only start a TPM 1.2.
Upon first start, libvirt will run `swtpm_setup`, which will simulate the
manufacturing of a TPM and create certificates for it and write them into
NVRAM locations of the emulated TPM.
After that libvirt starts the swtpm TPM emulator using the `swtpm` executable.
Once the VM terminates, libvirt uses the swtpm_ioctl executable to gracefully
shut down the `swtpm` in case it is still running (QEMU did not send shutdown)
or clean up the socket file.
The above mentioned executables must be found in the PATH.
The executables can either be run as root or started as root and switch to
the tss user. The requirement for the tss user comes through 'tcsd', which
is used for the simulation of the manufacturing. Which user is used can be
configured through qemu.conf. By default 'tss' is used.
The swtpm writes out state into files. The state is kept in /var/lib/libvirt/swtpm:
[root@localhost libvirt]# ls -lZ | grep swtpm
drwx--x--x. 7 root root unconfined_u:object_r:virt_var_lib_t:s0 4096 Apr 5 16:22 swtpm
The directory /var/lib/libvirt/swtpm maintains per-TPM state directories.
(Using the uuid of the VM for that since the name can change per VM renaming but
we need a stable directory name.)
[root@localhost swtpm]# ls -lZ
total 4
drwx------. 2 tss tss system_u:object_r:virt_var_lib_t:s0 4096 Apr 5 16:46 485d0004-a48f-436a-8457-8a3b73e28568
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28568]# ls -lZ
total 4
drwx------. 2 tss tss system_u:object_r:virt_var_lib_t:s0 4096 Apr 10 21:34 tpm1.2
[root@localhost tpm1.2]# ls -lZ
total 8
-rw-r--r--. 1 tss tss system_u:object_r:virt_var_lib_t:s0 3648 Apr 5 16:46 tpm-00.permall
The directory /var/run/libvirt/qemu/swtpm/ hosts the swtpm.sock that
QEMU uses to communicate with the swtpm:
root@localhost domain-1-testvm]# ls -lZ
total 0
srw-------. 1 qemu qemu system_u:object_r:svirt_image_t:s0:c597,c632 0 Apr 6 10:24 1-testvm-swtpm.sock
The logfile for the swtpm is in /var/log/swtpm/libvirt/qemu:
[root@localhost-3 qemu]# ls -lZ
total 4
-rw-------. 1 tss tss unconfined_u:object_r:var_log_t:s0 2199 Apr 6 14:01 testvm-swtpm.log
The processes are labeled as follows:
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep swtpm | grep socket | grep -v grep
system_u:system_r:virtd_t:s0-s0:c0.c1023 tss 18697 0.0 0.0 28172 3892 ? Ss 16:46 0:00 /usr/bin/swtpm socket --daemon --ctrl type=unixio,path=/var/run/libvirt/qemu/swtpm/1-testvm-swtpm.sock,mode=0600 --tpmstate dir=/var/lib/libvirt/swtpm/485d0004-a48f-436a-8457-8a3b73e28568/tpm1.2 --log file=/var/log/swtpm/libvirt/qemu/testvm-swtpm.log
[root@localhost 485d0004-a48f-436a-8457-8a3b73e28567]# ps auxZ | grep qemu | grep tpm | grep -v grep
system_u:system_r:svirt_t:s0:c413,c430 qemu 18702 2.5 0.0 3036052 48676 ? Sl 16:46 0:08 /bin/qemu-system-x86_64 [...]
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Implement functions for managing the storage of the external swtpm as well
as starting and stopping it. Also implement functions to use swtpm_setup,
which simulates the manufacturing of a TPM, which includes creation of
certificates for the device.
Further, the external TPM needs storage on the host that we need to set
up before it can be run. We can clean up the host once the domain is
undefined.
This patch also implements a small layer for external device support that
calls into the TPM device layer if a domain has an attached TPM. This is
the layer we will wire up later on.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend qemu_conf with user and group for running the tpm-emulator
and add directories to the configuration for the locations of the
log, state, and socket of the tpm-emulator.
Also add these new directories to the QEMU Makefile.inc.am and
the RPM spec file libvirt.spec.in.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend the DAC and SELinux modules with support for the tpm-emulator.
We label the Unix socket that QEMU connects to after starting swtmp
with DAC and SELinux labels. We do not have to restore the labels in
this case since the tpm-emulator will remove the Unix socket when it
terminates.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Implement virFileChownFiles() which changes file ownership of all
files in a given directory.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend the QEMU capabilities with tpm-emulator support.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This patch adds support for an external swtpm TPM emulator. The XML for
this type of TPM looks as follows:
<tpm model='tpm-tis'>
<backend type='emulator'/>
</tpm>
The XML will currently only define a TPM 1.2.
Extend the documentation.
Add a test case testing the XML parser and formatter.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Commit id 02b031a4 added a secondary path from which the
incoming @secinfo would not be free'd until the private
data was freed in qemuDomainStorageSourcePrivateDispose.
However, by doing this the original intention to free
@*secinfo afterwards is lost and thus the pass by value
of the secinfo->s.aes (or secinfo->s.plain for its method)
results in not keeping the NULL setting in the various
secret.{username|iv|ciphertext} fields upon return to
qemuDomainSecretInfoClear and eventually will result in
a double free at domain destroy:
raise ()
abort ()
__libc_message ()
malloc_printerr ()
_int_free ()
virFree
qemuDomainSecretAESClear
qemuDomainSecretInfoClear
qemuDomainSecretInfoFree
qemuDomainStorageSourcePrivateDispose
virObjectUnref
virStorageSourceClear
virStorageSourceFree
virDomainDiskDefFree
virDomainDefFree
virDomainObjRemoveTransientDef
qemuProcessStop
qemuDomainDestroyFlags
virDomainDestroy
Signed-off-by: John Ferlan <jferlan@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
Instead of array of pointers to individual buffers it can be
array of buffers directly. This also fixes the following memleak:
==22516== 96 bytes in 4 blocks are definitely lost in loss record 166 of 195
==22516== at 0x4C2EF26: calloc (vg_replace_malloc.c:711)
==22516== by 0x5D2C7D5: virAlloc (viralloc.c:144)
==22516== by 0x56FAABD: qemuBuildNumaArgStr (qemu_command.c:7543)
==22516== by 0x5701835: qemuBuildCommandLine (qemu_command.c:10112)
==22516== by 0x575D794: qemuProcessCreatePretendCmd (qemu_process.c:6568)
==22516== by 0x113338: testCompareXMLToArgv (qemuxml2argvtest.c:549)
==22516== by 0x138CA3: virTestRun (testutils.c:180)
==22516== by 0x136CD1: mymain (qemuxml2argvtest.c:2825)
==22516== by 0x13AD58: virTestMain (testutils.c:1118)
==22516== by 0x137351: main (qemuxml2argvtest.c:2874)
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This function exists because of 5276ec712a. But it is
missing initial check just like virQEMUCapsInitHostCPUModel()
has.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The default NBD TLS certificate path varies based on prefix given to
configure, causing tests to fail depending on build options.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Replace instances where we previously called virGetLastError just to
either get the code or to check if an error exists with
virGetLastErrorCode to avoid a validity pre-check.
Signed-off-by: Ramy Elkest <ramyelkest@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
Many places in the code call virGetLastError() just to check the
raised error code, or domain. However virGetLastError() can return
NULL, so the code has to check for that first. This patch therefore
introduces virGetLasError{Code,Domain} functions which always return a
valid error code or domain respectively, thus dropping the need to
perform any checks on the error object.
Signed-off-by: Ramy Elkest <ramyelkest@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>