Declare what URI schemes a driver supports in its virConnectDriver
struct. This allows us to skip trying to open the driver entirely
if the URI scheme doesn't match.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Add a localOnly flag to the virConnectDriver struct which allows a
driver to indicate whether it is local-only, or permits remote
connections. Stateful drivers running inside libvirtd are generally
local only. This allows us to remote the check for uri->server != NULL
from most drivers.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Allow the possibility of opening a connection to only the secret
driver, by defining secret:///system and secret:///session URIs
and registering a fake hypervisor driver that supports them.
The hypervisor drivers can now directly open a secret driver
connection at time of need, instead of having to pass around a
virConnectPtr through many functions. This will facilitate the later
change to support separate daemons for each driver.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Rather than rely on virSecretObjEndAPI to make the final virObjectUnref
after the call to virSecretObjListRemove, be more explicit by calling
virObjectUnref and setting @obj to NULL for secretUndefine and in
the error path of secretDefineXML. Calling EndAPI will end up calling
Unlock on an already unlocked object which has indeteriminate results
(usually an ignored error).
The virSecretObjEndAPI will both Unref and Unlock the object; however,
the virSecretObjListRemove would have already Unlock'd the object so
calling Unlock again is incorrect. Once the virSecretObjListRemove
is called all that's left is to Unref our interest since that's the
corrollary to the virSecretObjListAdd which returned our ref interest
plus references for each hash table in which the object resides. In math
terms, after an Add there's 2 refs on the object (1 for the object and
1 for the list). After calling Remove there's just 1 ref on the object.
For the Add callers, calling EndAPI removes the ref for the object and
unlocks it, but since it's in a list the other 1 remains.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Since the virSecretObjListAdd technically consumes @def on success,
the secretDefineXML should set @def = NULL immediately and process
the remaining calls using a new @objDef variable. We can use use
VIR_STEAL_PTR since we know the Add function just stores @def in
obj->def.
Because we steal @def into @objDef, if we jump to restore_backup:
and @backup is set, then we need to ensure the @def would be
free'd properly, so we'll steal it back from @objDef. For the other
condition this fixes a double free of @def if the code had jumped to
@backup == NULL thus calling virSecretObjListRemove without setting
@def = NULL. In this case, the subsequent call to DefFree would
succeed and free @def; however, the call to EndAPI would also
call DefFree because the Unref done would be the last one for
the @obj meaning the obj->def would be used to call DefFree,
but it's already been free'd because @def wasn't managed right
within this error path.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Since we're storing a virUUIDFormat'd string in our Hash Table, let's
modify the Lookup API to receive a formatted string as well.
Signed-off-by: John Ferlan <jferlan@redhat.com>
If a remote call fails during event registration (more than likely from
a network failure or remote libvirtd restart timed just right), then when
calling the virObjectEventStateDeregisterID we don't want to call the
registered @freecb function because that breaks our contract that we
would only call it after succesfully returning. If the @freecb routine
were called, it could result in a double free from properly coded
applications that free their opaque data on failure to register, as seen
in the following details:
Program terminated with signal 6, Aborted.
#0 0x00007fc45cba15d7 in raise
#1 0x00007fc45cba2cc8 in abort
#2 0x00007fc45cbe12f7 in __libc_message
#3 0x00007fc45cbe86d3 in _int_free
#4 0x00007fc45d8d292c in PyDict_Fini
#5 0x00007fc45d94f46a in Py_Finalize
#6 0x00007fc45d960735 in Py_Main
#7 0x00007fc45cb8daf5 in __libc_start_main
#8 0x0000000000400721 in _start
The double dereference of 'pyobj_cbData' is triggered in the following way:
(1) libvirt_virConnectDomainEventRegisterAny is invoked.
(2) the event is successfully added to the event callback list
(virDomainEventStateRegisterClient in
remoteConnectDomainEventRegisterAny returns 1 which means ok).
(3) when function remoteConnectDomainEventRegisterAny is hit,
network connection disconnected coincidently (or libvirtd is
restarted) in the context of function 'call' then the connection
is lost and the function 'call' failed, the branch
virObjectEventStateDeregisterID is therefore taken.
(4) 'pyobj_conn' is dereferenced the 1st time in
libvirt_virConnectDomainEventFreeFunc.
(5) 'pyobj_cbData' (refered to pyobj_conn) is dereferenced the
2nd time in libvirt_virConnectDomainEventRegisterAny.
(6) the double free error is triggered.
Resolve this by adding a @doFreeCb boolean in order to avoid calling the
freeCb in virObjectEventStateDeregisterID for any remote call failure in
a remoteConnect*EventRegister* API. For remoteConnect*EventDeregister* calls,
the passed value would be true indicating they should run the freecb if it
exists; whereas, it's false for the remote call failure path.
Patch based on the investigation and initial patch posted by
fangying <fangying1@huawei.com>.
Rather than waiting for the first save to fail, let's generate the
directory with the correct privs during initialization.
Signed-off-by: John Ferlan <jferlan@redhat.com>
When processing a virSecretPtr use 'secret' as a variable name.
When processing a virSecretObjPtr use 'obj' as a variable name.
When processing a virSecretDefPtr use 'def' as a variable name,
unless a distinction needs to be made with a 'newdef' such as
virSecretObjListAddLocked (which also used the VIR_STEAL_PTR macro
for the configFile and base64File).
Signed-off-by: John Ferlan <jferlan@redhat.com>
The public virSecret object has a single "usage_id" field
but the virSecretDef object has a different 'char *' field
for each usage type, but the code all assumes every usage
type has a corresponding single string. Get rid of the
pointless union in virSecretDef and just use "usage_id"
everywhere. This doesn't impact public XML format, only
the internal handling.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Move the enum into a new src/util/virsecret.h, rename it to be
virSecretLookupType. Add a src/util/virsecret.h in order to perform
a couple of simple operations on the secret XML and virSecretLookupTypeDef
for clearing and copying.
This includes quite a bit of collateral damage, but the goal is to remove
the "virStorage*" and replace with the virSecretLookupType so that it's
easier to to add new lookups that aren't necessarily storage pool related.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Rather than returning a "char *" indicating perhaps some sized set of
characters that is NUL terminated, alter the function to return 0 or -1
for success/failure and add two parameters to handle returning the
buffer and it's size.
The function no longer encodes the returned secret, rather it returns
the unencoded secret forcing callers to make the necessary adjustments.
Alter the callers to handle the adjusted model.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Call the internal driver callbacks rather than the public APIs to avoid
calling unnecessarily the error dispatching code and don't overwrite
the error messages provided by the APIs. They are good enough to
describe which secret is missing either by UUID or the usage (basically
name).
Introduce the final accessor's to _virSecretObject data and move the
structure from virsecretobj.h to virsecretobj.c
The virSecretObjSetValue logic will handle setting both the secret
value and the value_size. Some slight adjustments to the error path
over what was in secretSetValue were made.
Additionally, a slight logic change in secretGetValue where we'll
check for the internalFlags and error out before checking for
and erroring out for a NULL secret->value. That way, it won't be
obvious to anyone that the secret value wasn't set rather they'll
just know they cannot get the secret value since it's private.
Move and rename the secretRewriteFile, secretSaveDef, and secretSaveValue
from secret_driver to virsecretobj
Need to make some slight adjustments since the secretSave* functions
called secretEnsureDirectory, but otherwise mostly just a move of code.
Move and rename secretDeleteSaved from secret_driver into virsecretobj and
split it up into two parts since there is error path code that looks to
just delete the secret data file
Move to secret_conf.c and rename to virSecretLoadAllConfigs. Also includes
moving/renaming the supporting virSecretLoad, virSecretLoadValue, and
virSecretLoadValidateUUID.
This patch replaces most of the guts of secret_driver.c with recently
added secret_conf.c APIs in order manage secret lists and objects
using the hashed virSecretObjList* lookup API's.
Move virSecretObj from secret_driver.c to virsecretobj.h
To support being able to create a hashed secrets list, move the
virSecretObj to virsecretobj.h so that the code can at least find
the definition.
This should be a temporary situation while the virsecretobj.c code
is patched in order to support a hashed secret object while still
having the linked list support in secret_driver.c. Eventually, the
goal is to move the virSecretObj into virsecretobj.c, although it
is notable that the existing model from which virSecretObj was
derived has virDomainObj in src/conf/domain_conf.h and virNetworkObj
in src/conf/network_conf.h, so virSecretObj wouldn't be unique if
it were to remain in virsecretobj.h Still adding accessors to fetch
and store hashed object data will be the end goal.
Add definitions and infrastucture in virsecretobj.c to create and
handle a hashed virSecretObj and virSecretObjList including the class,
object, lock setup, and disposal API's. Nothing will call these yet.
This infrastructure will replace the forward linked list logic
within the secret_driver, eventually.
Commit id 'fb2bd208' essentially copied the qemuGetSecretString
creating an libxlGetSecretString. Rather than have multiple copies
of the same code, create src/secret/secret_util.{c,h} files and
place the common function in there.
Modify the the build in order to build the module as a library
which is then pulled in by both the qemu and libxl drivers for
usage from both qemu_command.c and libxl_conf.c
This new API will allocate the secret, assign the def pointer, and
insert the secret onto the passed list. Whether that's the temporary
list in loadSecrets which gets loaded into the driver list or driver
list during secretDefineXML.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Add a temporary helper to search for a specific secret by address
on the list and remove it if it's found. The following patch will
introduce a common allocation and listInsert helper. That means
error paths of the routines calling would need a way to remove the
secret off the list.
Signed-off-by: John Ferlan <jferlan@redhat.com>
This patch removes need for secretBase64Path and secretComputePath. Similar
to the configFile, create an entry for base64File, which will be generated
as the driver->configDir, the UUID value, plus the ".base" suffix. Rather
than generating on the fly, store this in the virSecretObj.
The buildup of the pathname done in loadSecrets where the failure to build
is ignored which is no different than the failure to generate the name
in secretLoadValue which would have been ignored in the failure path
after secretLoad.
This also removes the need for secretComputPath and secretBase64Path.
Signed-off-by: John Ferlan <jferlan@redhat.com>
This patch removes the need for secretXMLPath. Instead save 'path' during
loadSecret as 'configFile'. The secretXMLPath is nothing more than an
open coded virFileBuildPath. All that code did was concantenate the
driver->configDir, the UUID of the secret, and the ".xml" suffix to form
the configFile name which we now will generate and save instead.
Signed-off-by: John Ferlan <jferlan@redhat.com>
The 'secretLoad' was essentially open coding virFileBuildPath.
Adjust the logic to have the caller build the path and pass it. The net
sum of ignoring the virFileBuildPath failure is the same as before where
the failure to virAsprintf the path would have been ignored anyway in
the secretLoad error path.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Remove the need for the local 'secret' in secretConnectListAllSecrets.
A subsequent patch will rename the ObjPtr entry to secret.
Signed-off-by: John Ferlan <jferlan@redhat.com>
Rather than having it interspersed with other changes, do it once.
Remove a couple ^L, 1 argument per line for functions, less than 80 chars
per line, use of spacing between logical groups of code, use of one line
if statements when doing fetch followed by comparison, use direct return
when no cleanup to be done.
Signed-off-by: John Ferlan <jferlan@redhat.com>
For stateless, client side drivers, it is never correct to
probe for secondary drivers. It is only ever appropriate to
use the secondary driver that is associated with the
hypervisor in question. As a result the ESX & HyperV drivers
have both been forced to do hacks where they register no-op
drivers for the ones they don't implement.
For stateful, server side drivers, we always just want to
use the same built-in shared driver. The exception is
virtualbox which is really a stateless driver and so wants
to use its own server side secondary drivers. To deal with
this virtualbox has to be built as 3 separate loadable
modules to allow registration to work in the right order.
This can all be simplified by introducing a new struct
recording the precise set of secondary drivers each
hypervisor driver wants
struct _virConnectDriver {
virHypervisorDriverPtr hypervisorDriver;
virInterfaceDriverPtr interfaceDriver;
virNetworkDriverPtr networkDriver;
virNodeDeviceDriverPtr nodeDeviceDriver;
virNWFilterDriverPtr nwfilterDriver;
virSecretDriverPtr secretDriver;
virStorageDriverPtr storageDriver;
};
Instead of registering the hypervisor driver, we now
just register a virConnectDriver instead. This allows
us to remove all probing of secondary drivers. Once we
have chosen the primary driver, we immediately know the
correct secondary drivers to use.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Since virSecretFree will call virObjectUnref anyway, let's just use that
directly so as to avoid the possibility that we inadvertently clear out
a pending error message when using the public API.
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: Eric Blake <eblake@redhat.com>
Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Coverity found an issue in lxc_driver and uml_driver that we don't
check the return value of register functions.
I've also updated all other places and unify the way we check the
return value.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
Ensure that all drivers implementing public APIs use a
naming convention for their implementation that matches
the public API name.
eg for the public API virDomainCreate make sure QEMU
uses qemuDomainCreate and not qemuDomainStart
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It will simplify later work if the sub-drivers have dedicated
APIs / field names. ie virNetworkDriver should have
virDrvNetworkOpen and virDrvNetworkClose methods
Signed-off-by: Daniel P. Berrange <berrange@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: Daniel P. Berrange <berrange@redhat.com>
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: Daniel 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: Daniel P. Berrange <berrange@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=871756
Commit cd1e8d1 assumed that systems new enough to have journald
also have mkostemp; but this is not true for uclibc.
For that matter, use of mkstemp[s] is unsafe in a multi-threaded
program. We should prefer mkostemp[s] in the first place.
* bootstrap.conf (gnulib_modules): Add mkostemp, mkostemps; drop
mkstemp and mkstemps.
* cfg.mk (sc_prohibit_mkstemp): New syntax check.
* tools/virsh.c (vshEditWriteToTempFile): Adjust caller.
* src/qemu/qemu_driver.c (qemuDomainScreenshot)
(qemudDomainMemoryPeek): Likewise.
* src/secret/secret_driver.c (replaceFile): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainScreenshot): Likewise.
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/
When trying to get the value of a private secret, the code used
'operation denied' error. That error is specified as a error for
read-only connections trying to perform denied operation. The
following error seems more accurate.
To compare the difference:
- BEFORE
error: operation secret is private forbidden for read only access
- AFTER
error: Invalid secret: secret is private
Simply returns the object list. Supports to filter the secrets
by its storage location, and whether it's private or not.
src/secret/secret_driver.c: Implement listAllSecrets
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
Update the secret driver to use virReportError instead of the
virSecretReportError custom macro
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Remove the uid param from virGetUserConfigDirectory,
virGetUserCacheDirectory, virGetUserRuntimeDirectory,
and virGetUserDirectory
These functions were universally called with the
results of getuid() or geteuid(). To make it practical
to port to Win32, remove the uid parameter and hardcode
geteuid()
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
As defined in:
http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
This offers a number of advantages:
* Allows sharing a home directory between different machines, or
sessions (eg. using NFS)
* Cleanly separates cache, runtime (eg. sockets), or app data from
user settings
* Supports performing smart or selective migration of settings
between different OS versions
* Supports reseting settings without breaking things
* Makes it possible to clear cache data to make room when the disk
is filling up
* Allows us to write a robust and efficient backup solution
* Allows an admin flexibility to change where data and settings are stored
* Dramatically reduces the complexity and incoherence of the
system for administrators
Add a new secret type to store a Ceph authentication key. The name
is simply an identifier for easy human reference.
The xml looks like this:
<secret ephemeral='no' private='no'>
<uuid>0a81f5b2-8403-7b23-c8d6-21ccc2f80d6f</uuid>
<usage type='ceph'>
<name>mycluster_admin</name>
</usage>
</secret>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.net>
There were two API in driver.c that were silently masking flags
bits prior to calling out to the drivers, and several others
that were explicitly masking flags bits. This is not
forward-compatible - if we ever have that many flags in the
future, then talking to an old server that masks out the
flags would be indistinguishable from talking to a new server
that can honor the flag. In general, libvirt.c should forward
_all_ flags on to drivers, and only the drivers should reject
unknown flags.
In the case of virDrvSecretGetValue, the solution is to separate
the internal driver callback function to have two parameters
instead of one, with only one parameter affected by the public
API. In the case of virDomainGetXMLDesc, it turns out that
no one was ever mixing VIR_DOMAIN_XML_INTERNAL_STATUS with
the dumpxml path in the first place; that internal flag was
only used in saving and restoring state files, which happened
to be in functions internal to a single file, so there is no
mixing of the internal flag with a public flags argument.
Additionally, virDomainMemoryStats passed a flags argument
over RPC, but not to the driver.
* src/driver.h (VIR_DOMAIN_XML_FLAGS_MASK)
(VIR_SECRET_GET_VALUE_FLAGS_MASK): Delete.
(virDrvSecretGetValue): Separate out internal flags.
(virDrvDomainMemoryStats): Provide missing flags argument.
* src/driver.c (verify): Drop unused check.
* src/conf/domain_conf.h (virDomainObjParseFile): Delete
declaration.
(virDomainXMLInternalFlags): Move...
* src/conf/domain_conf.c: ...here. Delete redundant include.
(virDomainObjParseFile): Make static.
* src/libvirt.c (virDomainGetXMLDesc, virSecretGetValue): Update
clients.
(virDomainMemoryPeek, virInterfaceGetXMLDesc)
(virDomainMemoryStats, virDomainBlockPeek, virNetworkGetXMLDesc)
(virStoragePoolGetXMLDesc, virStorageVolGetXMLDesc)
(virNodeNumOfDevices, virNodeListDevices, virNWFilterGetXMLDesc):
Don't mask unknown flags.
* src/interface/netcf_driver.c (interfaceGetXMLDesc): Reject
unknown flags.
* src/secret/secret_driver.c (secretGetValue): Update clients.
* src/remote/remote_driver.c (remoteSecretGetValue)
(remoteDomainMemoryStats): Likewise.
* src/qemu/qemu_process.c (qemuProcessGetVolumeQcowPassphrase):
Likewise.
* src/qemu/qemu_driver.c (qemudDomainMemoryStats): Likewise.
* daemon/remote.c (remoteDispatchDomainMemoryStats): Likewise.
Detected by Coverity. The only ways to get to the cleanup label
were by an early abort (list still unassigned) or after successfully
transferring list to dest, so there is no list to clean up.
* src/secret/secret_driver.c (loadSecrets): Kill dead code.
These VIR_XXXX0 APIs make us confused, use the non-0-suffix APIs instead.
How do these coversions works? The magic is using the gcc extension of ##.
When __VA_ARGS__ is empty, "##" will swallow the "," in "fmt," to
avoid compile error.
example: origin after CPP
high_level_api("%d", a_int) low_level_api("%d", a_int)
high_level_api("a string") low_level_api("a string")
About 400 conversions.
8 special conversions:
VIR_XXXX0("") -> VIR_XXXX("msg") (avoid empty format) 2 conversions
VIR_XXXX0(string_literal_with_%) -> VIR_XXXX(%->%%) 0 conversions
VIR_XXXX0(non_string_literal) -> VIR_XXXX("%s", non_string_literal)
(for security) 6 conversions
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Using automated replacement with sed and editing I have now replaced all
occurrences of close() with VIR_(FORCE_)CLOSE() except for one, of
course. Some replacements were straight forward, others I needed to pay
attention. I hope I payed attention in all the right places... Please
have a look. This should have at least solved one more double-close
error.
The virConnectPtr is no longer required for error reporting since
that is recorded in a thread local. Remove use of virConnectPtr
from all APIs in secret_conf.{h,c} and update all callers to
match
I noticed some debug messages are printed with an empty lines after
them. This patch removes these empty lines from all invocations of the
following macros:
VIR_DEBUG
VIR_DEBUG0
VIR_ERROR
VIR_ERROR0
VIR_INFO
VIR_WARN
VIR_WARN0
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The LXC driver was mistakenly returning -1 for lxcStartup()
in scenarios that are not an error. This caused the libvirtd
to quit for unprivileged users. This fixes the return code
of LXC driver, and also adds a "name" field to the virStateDriver
struct and logging to make it easier to find these problems
in the future
* src/driver.h: Add a 'name' field to state driver to allow
easy identification during failures
* src/libvirt.c: Log name of failed driver for virStateInit
failures
* src/lxc/lxc_driver.c: Don't return a failure code for
lxcStartup() if LXC is not available on this host, simply
disable the driver.
* src/network/bridge_driver.c, src/node_device/node_device_devkit.c,
src/node_device/node_device_hal.c, src/opennebula/one_driver.c,
src/qemu/qemu_driver.c, src/remote/remote_driver.c,
src/secret/secret_driver.c, src/storage/storage_driver.c,
src/uml/uml_driver.c, src/xen/xen_driver.c: Fill in name
field in virStateDriver struct
