Use virObject to virHostdevManager, so that each driver using virHostdevManager
can keep a reference to it, and through counting refs to make virHostdevManager
get freed.

So far it's just virCommandSetDryRun.

Commit b9dd878f caused a regression in iptables interaction by
logging non-zero status at a higher level than VIR_INFO.  Revert
that portion of the commit, as well as adding a comment explaining
why we check the status ourselves.

Reported by Nehal J Wani.

* src/util/viriptables.c (virIpTablesOnceInit): Undo log regression.
Signed-off-by: NEric Blake <eblake@redhat.com>

The ebtablesRemoveForwardPolicyReject method was unused and
would not do anything useful even if called.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The ebtRules data structure serves no useful purpose as
the table name is never used and only 1 single chain name
needs to be stored. Just store the chain name directly
in the ebtablesContext instead.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When adding/removing ebtables rules, the code would keep
an array of all rules in memory. This list of rules was
never used for any purpose and would be lost if libvirtd
restarted. Delete all the unused code.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The input_filter and nat_postrouting variables were never
used to create any firewall rules.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The ebtablesForwardPolicyReject method is only used internally
to the ebtables code and thus should have been static.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

There is no impl of the ebtablesSaveRules method and nothing
attempts to use it.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The future QEMU capabilities cache needs to be able to invalidate
itself if the libvirtd binary or any loadable modules are changed
on disk. Record the 'ctime' value for these binaries and provide
helper APIs to query it. This approach assumes that if libvirt.so
is changed, then libvirtd will also change, which should usually
be the case with libtool's wrapper scripts that cause libvirtd to
get re-linked
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

GNULIB provides APIs for calculating md5 and sha256 hashes,
but these APIs only return you raw byte arrays. Most users
in libvirt want the hash in printable string format. Add
some helper APIs in util/vircrypto.{c,h} for doing this.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Some of these are leftovers from renaming the files, others
are just typos.

Also introduce an ugly awk script to enforce this.

Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This resolves a Coverity RESOURCE_LEAK issue introduced by commit
id 'de6fa535' where the virSCSIDeviceSetUsedBy() didn't VIR_FREE
the 'copy' or possibly VIR_STRDUP()'d values.  It also ensures that
the VIR_APPEND_ELEMENT is successful...

If SELinux is compiled into libvirt but it is disabled on the host,
libvirtd logs:

  error : virIdentityGetSystem:173 : Unable to lookup SELinux process
  context: Invalid argument

on each and every client connection.

Use is_selinux_enabled() to skip retrieval of the process's SELinux
context if SELinux is disabled.
Signed-off-by: NMichael Chapman <mike@very.puzzling.org>

Signed-off-by: NChunyan Liu <cyliu@suse.com>

Specify which driver and which domain in used_by area to avoid conflict among
different drivers.
Signed-off-by: NChunyan Liu <cyliu@suse.com>

If systemd is installed, but is not the init system,
systemd-machined fails with an unhelpful error message:
Launch helper exited with unknown return code 1

Currently we only check if the "machine1" service is
available (in ListActivatableNames).
Also check if "systemd1" service is registered with DBus
(ListNames).

This fixes https://bugs.gentoo.org/show_bug.cgi?id=493246#c22

Introduce virDBusIsServiceInList which can be used to call other
methods for listing services (ListNames), not just ListActivatableNames.

No functional change, fixed the 'Retruns' typo.

The old semantics of virFork() violates the priciple of good
usability: it requires the caller to check the pid argument
after use, *even when virFork returned -1*, in order to properly
abort a child process that failed setup done immediately after
fork() - that is, the caller must call _exit() in the child.
While uses in virfile.c did this correctly, uses in 'virsh
lxc-enter-namespace' and 'virt-login-shell' would happily return
from the calling function in both the child and the parent,
leading to very confusing results. [Thankfully, I found the
problem by inspection, and can't actually trigger the double
return on error without an LD_PRELOAD library.]

It is much better if the semantics of virFork are impossible
to abuse.  Looking at virFork(), the parent could only ever
return -1 with a non-negative pid if it misused pthread_sigmask,
but this never happens.  Up until this patch series, the child
could return -1 with non-negative pid if it fails to set up
signals correctly, but we recently fixed that to make the child
call _exit() at that point instead of forcing the caller to do
it.  Thus, the return value and contents of the pid argument are
now redundant (a -1 return now happens only for failure to fork,
a child 0 return only happens for a successful 0 pid, and a
parent 0 return only happens for a successful non-zero pid),
so we might as well return the pid directly rather than an
integer of whether it succeeded or failed; this is also good
from the interface design perspective as users are already
familiar with fork() semantics.

One last change in this patch: before returning the pid directly,
I found cases where using virProcessWait unconditionally on a
cleanup path of a virFork's -1 pid return would be nicer if there
were a way to avoid it overwriting an earlier message.  While
such paths are a bit harder to come by with my change to a direct
pid return, I decided to keep the virProcessWait change in this
patch.

* src/util/vircommand.h (virFork): Change signature.
* src/util/vircommand.c (virFork): Guarantee that child will only
return on success, to simplify callers.  Return pid rather than
status, now that the situations are always the same.
(virExec): Adjust caller, also avoid open-coding process death.
* src/util/virprocess.c (virProcessWait): Tweak semantics when pid
is -1.
(virProcessRunInMountNamespace): Adjust caller.
* src/util/virfile.c (virFileAccessibleAs, virFileOpenForked)
(virDirCreate): Likewise.
* tools/virt-login-shell.c (main): Likewise.
* tools/virsh-domain.c (cmdLxcEnterNamespace): Likewise.
* tests/commandtest.c (test23): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Auditing all callers of virCommandRun and virCommandWait that
passed a non-NULL pointer for exit status turned up some
interesting observations.  Many callers were merely passing
a pointer to avoid the overall command dying, but without
caring what the exit status was - but these callers would
be better off treating a child death by signal as an abnormal
exit.  Other callers were actually acting on the status, but
not all of them remembered to filter by WIFEXITED and convert
with WEXITSTATUS; depending on the platform, this can result
in a status being reported as 256 times too big.  And among
those that correctly parse the output, it gets rather verbose.
Finally, there were the callers that explicitly checked that
the status was 0, and gave their own message, but with fewer
details than what virCommand gives for free.

So the best idea is to move the complexity out of callers and
into virCommand - by default, we return the actual exit status
already cleaned through WEXITSTATUS and treat signals as a
failed command; but the few callers that care can ask for raw
status and act on it themselves.

* src/util/vircommand.h (virCommandRawStatus): New prototype.
* src/libvirt_private.syms (util/command.h): Export it.
* docs/internals/command.html.in: Document it.
* src/util/vircommand.c (virCommandRawStatus): New function.
(virCommandWait): Adjust semantics.
* tests/commandtest.c (test1): Test it.
* daemon/remote.c (remoteDispatchAuthPolkit): Adjust callers.
* src/access/viraccessdriverpolkit.c (virAccessDriverPolkitCheck):
Likewise.
* src/fdstream.c (virFDStreamCloseInt): Likewise.
* src/lxc/lxc_process.c (virLXCProcessStart): Likewise.
* src/qemu/qemu_command.c (qemuCreateInBridgePortWithHelper):
Likewise.
* src/xen/xen_driver.c (xenUnifiedXendProbe): Simplify.
* tests/reconnect.c (mymain): Likewise.
* tests/statstest.c (mymain): Likewise.
* src/bhyve/bhyve_process.c (virBhyveProcessStart)
(virBhyveProcessStop): Don't overwrite virCommand error.
* src/libvirt.c (virConnectAuthGainPolkit): Likewise.
* src/openvz/openvz_driver.c (openvzDomainGetBarrierLimit)
(openvzDomainSetBarrierLimit): Likewise.
* src/util/virebtables.c (virEbTablesOnceInit): Likewise.
* src/util/viriptables.c (virIpTablesOnceInit): Likewise.
* src/util/virnetdevveth.c (virNetDevVethCreate): Fix debug
message.
* src/qemu/qemu_capabilities.c (virQEMUCapsInitQMP): Add comment.
* src/storage/storage_backend_iscsi.c
(virStorageBackendISCSINodeUpdate): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Right now, a caller waiting for a child process either requires
the child to have status 0, or must use WIFEXITED() and friends
itself.  But in many cases, we want the middle ground of treating
fatal signals as an error, and directly accessing the normal exit
value without having to use WEXITSTATUS(), in order to easily
detect an expected non-zero exit status.  This adds the middle
ground to the low-level virProcessWait; the next patch will add
it to virCommand.

* src/util/virprocess.h (virProcessWait): Alter signature.
* src/util/virprocess.c (virProcessWait): Add parameter.
(virProcessRunInMountNamespace): Adjust caller.
* src/util/vircommand.c (virCommandWait): Likewise.
* src/util/virfile.c (virFileAccessibleAs): Likewise.
* src/lxc/lxc_container.c (lxcContainerHasReboot)
(lxcContainerAvailable): Likewise.
* daemon/libvirtd.c (daemonForkIntoBackground): Likewise.
* tools/virt-login-shell.c (main): Likewise.
* tools/virsh-domain.c (cmdLxcEnterNamespace): Likewise.
* tests/testutils.c (virtTestCaptureProgramOutput): Likewise.
* tests/commandtest.c (test23): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

The documentation of namespace callbacks was inconsistent on whether
it preserved positive return values.  Now that we have a dedicated
EXIT_CANCELED to flag all errors before getting to the callback,
it is possible to use positive return values (not that any of the
current callers do, but it is better to match the docs).

Also, while vircommand.c is careful to close fds that a child should
not have, it's still better to be in the practice of setting
FD_CLOEXEC up front.

* src/util/virprocess.c (virProcessRunInMountNamespace): Tweak
return value to pass back non-zero status.  Avoid leaking pipe fds
to other threads.
* src/util/virprocess.h: Fix comment.
Signed-off-by: NEric Blake <eblake@redhat.com>

Thanks to namespaces, we have a couple of places in the code
base that want to reflect a child exit status, including the
ability to detect death by a signal, back to a grandparent.
Best to make it a reusable function.

* src/util/virprocess.h (virProcessExitWithStatus): New prototype.
* src/libvirt_private.syms (util/virprocess.h): Export it.
* src/util/virprocess.c (virProcessExitWithStatus): New function.
* tests/commandtest.c (test23): Test it.
Signed-off-by: NEric Blake <eblake@redhat.com>

When a child fails without exec'ing, we want a well-known status;
best is to match what env(1), nice(1), su(1), and other wrapper
programs do.  This patch adds enum values that later patches will
use, and sets up virFork as the first client of EXIT_CANCELED
for errors detected prior to even attempting exec, as well as
virExec to distinguish between a missing executable vs. a binary
that cannot be executed.

This is a slight semantic change in the unlikely case of a child
process failing to restore its signal mask - we now kill the
child with a known status instead of relying on the caller to
notice and do an appropriate _exit().  A subsequent patch will
make further cleanups based on an audit of all callers.

* src/internal.h (EXIT_CANCELED, EXIT_CANNOT_INVOKE)
(EXIT_ENOENT): New enum.
* src/util/vircommand.c (virFork): Document specific exit value if
child aborts early.
(virExec): Distinguish between various exec failures.
* tests/commandtest.c (test1): Enhance test.
(test22): New test.
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When a virError is raised, pass the error domain and code
onto the systemd journald using metadata fields.

This allows error messages to be queried by code eg

  $ journalctl LIBVIRT_CODE=43
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The systemd journal expects log record PRIORITY values to
be encoded using the syslog compatible numbering scheme,
not libvirt's own native numbering scheme. We must therefore
apply a conversion.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The systemd journal accepts arbitrary user specified log
fields. These can be passed into virLogMessage via the
virLogMetadata structure. Allow up to 5 custom fields to
be reported by libvirt callers.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

While running virscsitest, it was found that valgrind pointed out the following
memory leak:

==320== 5 bytes in 1 blocks are definitely lost in loss record 4 of 37
==320==    at 0x4A069EE: malloc (vg_replace_malloc.c:270)
==320==    by 0x3E6CE81171: strdup (strdup.c:43)
==320==    by 0x4CB28DF: virStrdup (virstring.c:554)
==320==    by 0x4CAC987: virSCSIDeviceSetUsedBy (virscsi.c:289)
==320==    by 0x402321: test2 (virscsitest.c:100)
==320==    by 0x403231: virtTestRun (testutils.c:199)
==320==    by 0x402121: mymain (virscsitest.c:180)
==320==    by 0x4039AD: virtTestMain (testutils.c:782)
==320==    by 0x3E6CE1ED1C: (below main) (libc-start.c:226)
==320==

Introduced by commit fd243fc4.
Signed-off-by: NJán Tomko <jtomko@redhat.com>

Consider dozen of LXC domains, each of them having this type of interface:

    <interface type='network'>
      <mac address='52:54:00:a7:05:4b'/>
      <source network='default'/>
    </interface>

When starting these domain in parallel, all workers may meet in
virNetDevVethCreate() where a race starts. Race over allocating veth
pairs because allocation requires two steps:

  1) find first nonexistent '/sys/class/net/vnet%d/'
  2) run 'ip link add ...' command

Now consider two threads. Both of them find N as the first unused veth
index but only one of them succeeds allocating it. The other one fails.
For such cases, we are running the allocation in a loop with 10 rounds.
However this is very flaky synchronization. It should be rather used
when libvirt is competing with other process than when libvirt threads
fight each other. Therefore, internally we should use mutex to serialize
callers, and do the allocation in loop (just in case we are competing
with a different process). By the way we have something similar already
since 1cf97c87.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Running ./autobuild.sh detected a mingw failure:

  CCLD     libvirt.la
Cannot export virCgroupGetPercpuStats: symbol not defined
Cannot export virCgroupSetOwner: symbol not defined

* src/util/vircgroup.c (virCgroupGetPercpuStats)
(virCgroupSetOwner): Implement stubs.
Signed-off-by: NEric Blake <eblake@redhat.com>

This function is needed for user namespaces, where we need to chmod()
the cgroup to the initial uid/gid such that systemd is allowed to
use the cgroup.
Signed-off-by: NRichard Weinberger <richard@nod.at>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add a virStringReplace method to virstring.{h,c} to perform
substring matching and replacement
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Add a virStringSearch method to virstring.{c,h} which performs
a regex match against a string and returns the matching substrings.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Systemd does not forget about the cases, where client service needs to
wait for daemon service to initialize and start accepting new clients.
Setting a dependency in client is not enough as systemd doesn't know
when the daemon has initialized itself and started accepting new
clients. However, it offers a mechanism to solve this. The daemon needs
to call a special systemd function by which the daemon tells "I'm ready
to accept new clients". This is exactly what we need with
libvirtd-guests (client) and libvirtd (daemon). So now, with this
change, libvirt-guests.service is invoked not any sooner than
libvirtd.service calls the systemd notify function.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1031696

When creating a new domain, we let systemd know about it by calling
CreateMachine() function via dbus. Systemd then creates a scope and
places domain into it. However, later when the host is shutting
down, systemd computes the shutdown order to see what processes can
be shut down in parallel. And since we were not setting
dependencies at all, the slices (and thus domains) were most likely
killed before libvirt-guests.service. So user domains that had to
be saved, shut off, whatever were in fact killed.  This problem can
be solved by letting systemd know that scopes we're creating must
not be killed before libvirt-guests.service.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Commit 65158899 broke the build on FreeBSD:
In function `qemuDomainGetCPUStats':
/../../src/qemu/qemu_driver.c:16102:
undefined reference to `virCgroupGetDomainTotalCpuStats'