Now that all clients have been adjusted, ensure that no future
misuse of readdir is introduced into the code base.

* cfg.mk (sc_prohibit_readdir): New rule.
* src/util/virfile.c (virDirRead): Exempt the wrapper.
Signed-off-by: NEric Blake <eblake@redhat.com>

This attempts to follow the same variable name and usage patterns as
the other conversions to virDirRead().

More instances of failure to report (unlikely) readdir errors.
In one case, I chose to ignore them, given that a readdir error
would be no different than timing out on the loop, where the
fallback path behaves correctly either way.

* src/storage/storage_backend.c (virStorageBackendStablePath):
Ignore readdir errors.
* src/storage/storage_backend_fs.c
(virStorageBackendFileSystemRefresh): Report readdir errors.
* src/storage/storage_backend_iscsi.c
(virStorageBackendISCSIGetHostNumber): Likewise.
* src/storage/storage_backend_scsi.c (getNewStyleBlockDevice)
(getBlockDevice, virStorageBackendSCSIFindLUs): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Convert all remaining clients of readdir to use the new
interface, so that we can ensure (unlikely) errors while
reading a directory are reported.

* src/openvz/openvz_conf.c (openvzAssignUUIDs): Use new
interface.
* src/parallels/parallels_storage.c (parallelsFindVolumes)
(parallelsFindVmVolumes): Report readdir failures.
* src/qemu/qemu_driver.c (qemuDomainSnapshotLoad): Ignore readdir
failures.
* src/secret/secret_driver.c (loadSecrets): Likewise.
* src/qemu/qemu_hostdev.c
(qemuHostdevHostSupportsPassthroughVFIO): Report readdir failures.
* src/xen/xen_inotify.c (xenInotifyOpen): Likewise.
* src/xen/xm_internal.c (xenXMConfigCacheRefresh): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

In making the conversion to the new API, I fixed a couple bugs:
virSCSIDeviceGetSgName would leak memory if a directory
unexpectedly contained multiple entries;
virNetDevTapGetRealDeviceName could report a spurious error
from a stale errno inherited before starting the readdir search.

The decision on whether to store the result of virDirRead into
a variable is based on whether the end of the loop falls through
to cleanup code automatically.  In some cases, we have loops that
are documented to return NULL on failure, and which raise an
error on most failure paths but not in the case where the directory
was unexpectedly empty; it may be worth a followup patch to
explicitly report an error if readdir was successful but the
directory was empty, so that a NULL return always has an error set.

* src/util/vircgroup.c (virCgroupRemoveRecursively): Use new
interface.
(virCgroupKillRecursiveInternal, virCgroupSetOwner): Report
readdir failures.
* src/util/virfile.c (virFileLoopDeviceOpenSearch)
(virFileNBDDeviceFindUnused, virFileDeleteTree): Use new
interface.
* src/util/virnetdevtap.c (virNetDevTapGetRealDeviceName):
Properly check readdir errors.
* src/util/virpci.c (virPCIDeviceIterDevices)
(virPCIDeviceFileIterate, virPCIGetNetName): Report readdir
failures.
(virPCIDeviceAddressIOMMUGroupIterate): Use new interface.
* src/util/virscsi.c (virSCSIDeviceGetSgName): Report readdir
failures, and avoid memory leak.
(virSCSIDeviceGetDevName): Report readdir failures.
* src/util/virusb.c (virUSBDeviceSearch): Report readdir
failures.
* src/util/virutil.c (virGetFCHostNameByWWN)
(virFindFCHostCapableVport): Report readdir failures.
Signed-off-by: NEric Blake <eblake@redhat.com>

When reading configuration files, we were silently ignoring
directory read failures.  While unlikely, we might as well
report them.

* src/conf/domain_conf.c (virDomainObjListLoadAllConfigs): Report
readdir errors.
* src/conf/network_conf.c (virNetworkLoadAllState)
(virNetworkLoadAllConfigs): Likewise.
* src/conf/nwfilter_conf.c (virNWFilterLoadAllConfigs): Likewise.
* src/conf/storage_conf.c (virStoragePoolLoadAllConfigs):
Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

This makes sure that errno is reset before readdir is called, even if
the loop does a 'continue'.

This fixes issue with musl libc which sets errno on sscanf. The
following 'continue' makes the errno be set before calling readdir.
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Signed-off-by: NEric Blake <eblake@redhat.com>

Introduce a wrapper for readdir. This helps us make sure that we always
set errno before calling readdir and it will make sure errors are
properly logged.
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

With xend on the way out, installations may not even have
/usr/sbin/xend, which results in the following error when the
drivers are probed

2014-04-28 18:21:19.271+0000: 22129: error : virCommandWait:2426 :
internal error: Child process (/usr/sbin/xend status) unexpected exit
status 127: libvirt:  error : cannot execute binary /usr/sbin/xend:
No such file or directory

Check for existence of /usr/sbin/xend before trying to run it with
the 'status' option.

The virFirewallAddRuleFull method originally had a single
compulsory virFirewallQueryCallback parameter. During dev
work though the ignoreErrors parameter was added and the
callback parameter made optional. The ATTRIBUTE_NONNULL
annotation was never removed though.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virnetsocket.c API is hardcoded to pass --timeout=30 to
any daemon it auto-starts. For inexplicable reasons the virtlockd
daemon did not implement the --timeout option, so it would
immediately exit on autostart with an error.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the lock plugin use virFileFindResource to find the
virtlockd daemon path, so that it executes the in-builddir
daemon if run from source tree.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the remote driver use virFileFindResource to find the
libvirt daemon path, so that it executes the in-builddir
daemon if run from source tree.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When a snapshot operation finishes we have to recheck the backing chain
of all disks involved in the snapshot. And we need to do that even if
the operation failed because some of the disks might have changed if
QEMU did not support transactions.

The check for a network being active during interface attach was being
done individually in several places (by both the lxc driver and the
qemu driver), but those places were too specific, leading to it *not*
being checked when allocating a connection/device from a macvtap or
hostdev network.

This patch puts a single check in networkAllocateActualDevice(), which
is always called before the any network interface is attached to any
type of domain. It also removes all the other now-redundant checks
from the lxc and qemu drivers.

NB: the following patches are prerequisites for this patch, in the
case that it is backported to any branch:

  440beeb7 network: fix virNetworkObjAssignDef and persistence
  8aaa5b68 network: create statedir during driver initialization
  b9e95491 network: change location of network state xml files
  411c5486 network: set macvtap/hostdev networks active if their state
          file exists

This fixes:

  https://bugzilla.redhat.com/show_bug.cgi?id=880483

libvirt attempts to determine at startup time which networks are
already active, and set their active flags. Previously it has done
this by assuming that all networks are inactive, then setting the
active flag if the network has a bridge device associated with it and
that bridge device exists. This is not useful for macvtap and hostdev
based networks, since they do not use a bridge device.

Of course the reason that such a check had to be done was that the
presence of a status file in the network "stateDir" couldn't be
trusted as an indicator of whether or not a network was active. This
was due to the network driver mistakenly using
/var/lib/libvirt/network to store the status files, rather than
/var/run/libvirt/network (similar to what is done by every other
libvirt driver that stores status xml for its objects). The difference
is that /var/run is cleared out when the host reboots, so you can be
assured that the state file you are seeing isn't just left over from a
previous boot of the host.

Now that the network driver has been switched to using
/var/run/libvirt/network for status, we can also modify it to assume
that any network with an existing status file is by definition active
- we do this when reading the status file. To fine tune the results,
networkFindActiveConfigs() is changed to networkUpdateAllState(),
and only sets active = 0 if the conditions for particular network
types are *not* met.

The result is that during the first run of libvirtd after the host
boots, there are no status files, so no networks are active. Any time
libvirtd is restarted, any network with a status file will be marked
as active (unless the network uses a bridge device and that device for
some reason doesn't exist).

For some reason these have been stored in /var/lib, although other
drivers (e.g. qemu and lxc) store their state files in /var/run.

It's much nicer to store state files in /var/run because it is
automatically cleared out when the system reboots. We can then use
existence of the state file as a convenient indicator of whether or
not a particular network is active.

Since changing the location of the state files by itself will cause
problems in the case of a *live* upgrade from an older libvirt that
uses /var/lib (because current status of active networks will be
lost), the network driver initialization has been modified to migrate
any network state files from /var/lib to /var/run.

This will not help those trying to *downgrade*, but in practice this
will only be problematic in two cases

1) If there are networks with network-wide bandwidth limits configured
   *and in use* by a guest during a downgrade to "old" libvirt. In this
   case, the class ID's used for that network's tc rules, as well as
   the currently in-use bandwidth "floor" will be forgotten.

2) If someone does this: 1) upgrade libvirt, 2) downgrade libvirt, 3)
   modify running state of network (e.g. add a static dhcp host, etc),
   4) upgrade. In this case, the modifications to the running network
   will be lost (but not any persistent changes to the network's
   config).

This directory should be created when the network driver is first
started up, not just when a dhcp daemon is run. This hasn't posed a
problem in the past, because the directory has always been
pre-existing.

Experimentation showed that if virNetworkCreateXML() was called for a
network that was already defined, and then the network was
subsequently shutdown, the network would continue to be persistent
after the shutdown (expected/desired), but the original config would
be lost in favor of the transient config sent in with
virNetworkCreateXML() (which would then be the new persistent config)
(obviously unexpected/not desired).

To fix this, virNetworkObjAssignDef() has been changed to

1) properly save/free network->def and network->newDef for all the
various combinations of live/active/persistent, including some
combinations that were previously considered to be an error but didn't
need to be (e.g. setting a "live" config for a network that isn't yet
active but soon will be - that was previously considered an error,
even though in practice it can be very useful).

2) automatically set the persistent flag whenever a new non-live
config is assigned to the network (and clear it when the non-live
config is set to NULL). the libvirt network driver no longer directly
manipulates network->persistent, but instead relies entirely on
virNetworkObjAssignDef() to do the right thing automatically.

After this patch, the following sequence will behave as expected:

virNetworkDefineXML(X)
virNetworkCreateXML(X') (same name but some config different)
virNetworkDestroy(X)

At the end of these calls, the network config will remain as it was
after the initial virNetworkDefine(), whereas previously it would take
on the changes given during virNetworkCreateXML().

Another effect of this tighter coupling between a) setting a !live def
and b) setting/clearing the "persistent" flag, is that future patches
which change the details of network lifecycle management
(e.g. upcoming patches to fix detection of "active" networks when
libvirtd is restarted) will find it much more difficult to break
persistence functionality.

This fixes the following make rpm warning:

warning: Installed (but unpackaged) file(s) found:
   /usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so.0
   /usr/lib64/libvirt/connection-driver/libvirt_driver_nwfilter.so.0.0.0

introduced in comit 8d559864Signed-off-by: NDwight Engen <dwight.engen@oracle.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Currently the driver only exposes the ability to connect to the serial console
of a Xen guest, which doesn't work for a PV guest. Since for an HVM guest the
serial devices are duplicated as consoles it is sufficient to just use the
console devices unconditionally.

Tested with the following bit of config XML:

<domain type='xen'>
  ...
  <devices>
    <console type='pty'>
      <target type='xen'/>
    </console>
  </devices>
</domain>

I have observed and tested this on ARM but I believe it also applies to x86 PV
guests.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Cc: Jim Fehlig <jfehlig@suse.com>
Cc: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Clark Laughlin <clark.laughlin@linaro.org>

Signed-off-by: NDwight Engen <dwight.engen@oracle.com>

dlfcn.h does not exist on Win32 so must only be used
conditionally
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Create a nwfilterxml2firewalltest to exercise the
ebiptables_driver.applyNewRules method with a variety of
different XML input files. The XML input files are taken
from the libvirt-tck nwfilter tests. While the nwfilter
tests verify the final state of the iptables chains, this
test verifies the set of commands invoked to create the
chains.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Remove all the left over code related to the direct invocation
of firewall-cmd/iptables/ip6tables/ebtables. This is all handled
by the virFirewallPtr APIs now.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Conver the ebiptablesDriverProbeStateMatch initialization
check to use the virFirewall APIs for querying iptables
version.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebtablesApplyNewRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebtablesApplyDropAllRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebtablesApplyDHCPOnlyRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebtablesApplyBasicRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebiptablesTearNewRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebtablesRemoveBasicRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebiptablesTearOldRules method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the nwfilter ebiptablesAllTeardown method to use the
virFirewall object APIs instead of creating shell scripts
using virBuffer APIs. This provides a performance improvement
through allowing direct use of firewalld dbus APIs and will
facilitate automated testing.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the virebtables.{c,h} files to use the new virFirewall
APIs for changing ebtables rules.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Using the virCommand dry run capability, capture iptables rules
created by various network XML documents.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The networkCheckRouteCollision, networkAddFirewallRules and
networkRemoveFirewallRules APIs all take a virNetworkObjPtr
instance, but only ever access the 'def' member. It thus
simplifies testing if the APIs are changed to just take a
virNetworkDefPtr instead
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Update the iptablesXXXX methods so that instead of directly
executing iptables commands, they populate rules in an
instance of virFirewallPtr. The bridge driver can thus
construct the ruleset and then invoke it in one operation
having rollback handled automatically.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The network and nwfilter drivers both have a need to update
firewall rules. The currently share no code for interacting
with iptables / firewalld. The nwfilter driver is fairly
tied to the concept of creating shell scripts to execute
which makes it very hard to port to talk to firewalld via
DBus APIs.

This patch introduces a virFirewallPtr object which is able
to represent a complete sequence of rule changes, with the
ability to have multiple transactional checkpoints with
rollbacks. By formally separating the definition of the rules
to be applied from the mechanism used to apply them, it is
also possible to write a firewall engine that uses firewalld
DBus APIs natively instead of via the slow firewalld-cmd.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>