Each new VM requires a new connection from libvirtd to virtlockd.
The default max clients limit in virtlockd of 20 is thus woefully
insufficient. virtlockd sockets are only accessible to matching
users, so there is no security need for such a tight limit. Make
it configurable and default to 1024.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlockd/libvirtd daemons had listed '?' as the short option
for --help. getopt_long uses '?' for any unknown option. We want
to be able to distinguish unknown options (which use EXIT_FAILURE)
from correct usage of help (which should use EXIT_SUCCESS). Thus
we should use 'h' as a short option for --help. Also add this to
the man page docs
The virtlockd/libvirtd daemons did not list any short option
for the --version arg. Add -V as a valid short option, since
-v is already used for --verbose.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlockd daemon supports an /etc/libvirt/virtlockd.conf
config file, but we never installed a default config, nor
created any augeas scripts. This change addresses that omission.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This configuration knob lets user to set the length of queue of
connection requests waiting to be accept()-ed by the daemon. IOW, it
just controls the @backlog passed to listen:
int listen(int sockfd, int backlog);
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>
Introduce annotations to all RPC messages to declare what
access control checks are required. There are two new
annotations defined:
@acl: <object>:<permission>
@acl: <object>:<permission>:<flagname>
Declare the access control requirements for the API. May be repeated
multiple times, if multiple rules are required.
<object> is one of 'connect', 'domain', 'network', 'storagepool',
'interface', 'nodedev', 'secret'.
<permission> is one of the permissions in access/viraccessperm.h
<flagname> indicates the rule only applies if the named flag
is set in the API call
@aclfilter: <object>:<permission>
Declare an access control filter that will be applied to a list
of objects being returned by an API. This allows the returned
list to be filtered to only show those the user has permissions
against
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Since PIDs can be reused, polkit prefers to be given
a (PID,start time) pair. If given a PID on its own,
it will attempt to lookup the start time in /proc/pid/stat,
though this is subject to races.
It is safer if the client app resolves the PID start
time itself, because as long as the app has the client
socket open, the client PID won't be reused.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A 'uri' parameter was added for the benefit of sanlock. This
causes a warning in the lockd driver though
2013-05-03 13:20:35.347+0000: 28403: error : virLockManagerLockDaemonNew:482 : internal error Unexpected parameter uri for object
Ignore this parameter, since lockd does not require it and it
is harmless if not used.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The lockd plugin for the lock manager was not correctly
handling the release of resource locks. This meant that
during migration, or when pausing a VM, the locks would
not get released. This in turn made it impossible to
resume the domain, or finish migration
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.
Currently the RPC protocol files can contain annotations after
the protocol enum eg
REMOTE_PROC_DOMAIN_SNAPSHOT_LIST_CHILDREN_NAMES = 247, /* autogen autogen priority:high */
This is not very extensible as the number of annotations grows.
Change it to use
/**
* @generate: both
* @priority: high
*/
REMOTE_PROC_DOMAIN_SNAPSHOT_LIST_CHILDREN_NAMES = 247,
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
In virLockSpaceProtocolDispatchNew() the returned value of lockspace from
virLockDaemonFindLockSpace() is overwritten by the virLockSpaceNew() return.
Coverity complains that it's unused.
In virLockSpaceProtocolDispatchCreateLockSpace() lockspace is also overwritten
in a similar manner resulting in the same Coverity message.
POSIX does not guarantee whether uid_t and gid_t are signed or
unsigned, nor does it guarantee whether they are smaller, same
size, or larger than int (or even the same size as one another).
Therefore, it is possible to have platforms where '(uid_t)-1==-1'
is false or where 'uid = gid = -1' sets uid to the wrong value,
thanks to integer promotion rules. The only portable way to use
the placeholder value of these two types is to always use a cast.
Thankfully, the issue is mostly theoretical - sanlock only
compiles on Linux for now, and on Linux, these types do not
suffer from strange promotion problems.
* src/locking/lock_driver_sanlock.c
(virLockManagerSanlockSetupLockspace, virLockManagerSanlockInit)
(virLockManagerSanlockCreateLease): Cast -1 to proper type before
comparing with uid_t or gid_t.
virtlockd.service could be installed to a configurable root,
but virtlockd.socket was hardcoded to installation into a
distro.
* src/Makefile.am (virtlockd.service, virtlockd.socket): Drop
unused substitutions.
* src/locking/virtlockd.socket.in (ListenStream): Don't hard-code
/var.
We had several different styles of .in conversion in our Makefiles:
ALLCAPS, @ALLCAPS@, @lower@, ::lower::
Canonicalize on one form, to make it easier to copy and paste
between .in files.
Also, we were using some non-portable sed constructs: \@ is an
undefined escape sequence (it happens to be @ itself in GNU sed,
but POSIX allows it to mean something else), as well as risky
behavior (failure to consistently quote things means a space
in $(sysconfdir) could throw things off; also, Autoconf recommends
using | rather than , or ! in the s||| operator, because | has to
be quoted in shell and is therefore less likely to appear in file
names than , or !).
Fix all of these uses to follow the same syntax.
* daemon/libvirtd.8.in: Switch to @var@.
* tools/virt-xml-validate.in: Likewise.
* tools/virt-pki-validate.in: Likewise.
* src/locking/virtlockd.init.in: Likewise.
* daemon/Makefile.am: Prefer | over ! in sed.
(libvirtd.8): Prefer consistent substitution.
(libvirtd.init, libvirtd.service): Avoid non-portable sed.
* tools/Makefile.am (libvirt-guests.sh, libvirt-guests.init)
(libvirt-guests.service): Likewise.
(virt-xml-validate, virt-pki-validate, virt-sanlock-cleanup):
Prefer consistent capitalization.
* src/Makefile.am (virtlockd.init, virtlockd.service)
(virtlockd.socket): Prefer consistent substitution.
Since sanlock doesn't run under root:root, we have chown()'ed the
__LIBVIRT__DISKS__ lease file to the user:group defined in the
sanlock config. However, when writing the patch I've forgot about
lease files for each disk (this is the
/var/lib/libvirt/sanlock/<md5>) file.
Currently, if sanlock is already registering a lockspace other
libvirtd instances (from other hosts) obtain -EINPROGRESS. On
sufficiently new sanlock, sanlock_inq_lockspace() is called,
which suspend execution until lockspace state is changed. With
current libvirt implementation, we fail to retry adding the
lockspace again but continue in error path. Therefore we produce
meaningless error message:
virLockManagerSanlockSetupLockspace:363 : Unable to add lockspace
/var/lib/libvirt/sanlock/__LIBVIRT__DISKS__: Success
qemudLoadDriverConfig:558 : Failed to load lock manager sanlock
We should try to re-add the lockspace after its state change to
be sure it was added successfully. In fact, with sufficiently new
sanlock we can just avoid dummy usleep() which is used if there's
no inquire API.
The default lockd driver behavour is to acquire leases
directly on the disk files. This introduces an alternative
mode, where leases are acquire indirectly on a file that
is based on a SHA256 hash of the disk filename.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This adds a 'lockd' lock driver which is just a client which
talks to the lockd daemon to perform all locking. This will
be the default lock driver for any hypervisor which needs one.
* src/Makefile.am: Add lockd.so plugin
* src/locking/lock_driver_lockd.c: Lockd driver impl
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlockd daemon maintains file locks on behalf of libvirtd
and any VMs it is running. These file locks must be held for as
long as any VM is running. If virtlockd itself ever quits, then
it is expected that a node would be fenced/rebooted. Thus to
allow for software upgrads on live systemd, virtlockd needs the
ability to re-exec() itself.
Upon receipt of SIGUSR1, virtlockd will save its current live
state out to a file /var/run/virtlockd-restart-exec.json
It then re-exec()'s itself with exactly the same argv as it
originally had, and loads the state file, reconstructing any
objects as appropriate.
The state file contains information about all locks held and
all network services and clients currently active. An example
state document is
{
"server": {
"min_workers": 1,
"max_workers": 20,
"priority_workers": 0,
"max_clients": 20,
"keepaliveInterval": 4294967295,
"keepaliveCount": 0,
"keepaliveRequired": false,
"services": [
{
"auth": 0,
"readonly": false,
"nrequests_client_max": 1,
"socks": [
{
"fd": 6,
"errfd": -1,
"pid": 0,
"isClient": false
}
]
}
],
"clients": [
{
"auth": 0,
"readonly": false,
"nrequests_max": 1,
"sock": {
"fd": 9,
"errfd": -1,
"pid": 0,
"isClient": true
},
"privateData": {
"restricted": true,
"ownerPid": 1722,
"ownerId": 6,
"ownerName": "f18x86_64",
"ownerUUID": "97586ba9-df27-9459-c806-f016c8bbd224"
}
},
{
"auth": 0,
"readonly": false,
"nrequests_max": 1,
"sock": {
"fd": 10,
"errfd": -1,
"pid": 0,
"isClient": true
},
"privateData": {
"restricted": true,
"ownerPid": 1784,
"ownerId": 7,
"ownerName": "f16x86_64",
"ownerUUID": "7b8e5e42-b875-61e9-b981-91ad8fa46979"
}
}
]
},
"defaultLockspace": {
"resources": [
{
"name": "/var/lib/libvirt/images/f16x86_64.raw",
"path": "/var/lib/libvirt/images/f16x86_64.raw",
"fd": 14,
"lockHeld": true,
"flags": 0,
"owners": [
1784
]
},
{
"name": "/var/lib/libvirt/images/shared.img",
"path": "/var/lib/libvirt/images/shared.img",
"fd": 12,
"lockHeld": true,
"flags": 1,
"owners": [
1722,
1784
]
},
{
"name": "/var/lib/libvirt/images/f18x86_64.img",
"path": "/var/lib/libvirt/images/f18x86_64.img",
"fd": 11,
"lockHeld": true,
"flags": 0,
"owners": [
1722
]
}
]
},
"lockspaces": [
],
"magic": "30199"
}
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This enhancement virtlockd so that it can receive a pre-opened
UNIX domain socket from systemd at launch time, and adds the
systemd service/socket unit files
* daemon/libvirtd.service.in: Require virtlockd to be running
* libvirt.spec.in: Add virtlockd systemd files
* src/Makefile.am: Install systemd files
* src/locking/lock_daemon.c: Support socket activation
* src/locking/virtlockd.service.in, src/locking/virtlockd.socket.in:
systemd unit files
* src/rpc/virnetserverservice.c, src/rpc/virnetserverservice.h:
Add virNetServerServiceNewFD() method
* src/rpc/virnetsocket.c, src/rpc/virnetsocket.h: Add virNetSocketNewListenFD
method
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Introduce a lock_daemon_dispatch.c file which implements the
server side dispatcher the RPC APIs previously defined in the
lock protocol.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlockd daemon will be responsible for managing locks
on virtual machines. Communication will be via the standard
RPC infrastructure. This provides the XDR protocol definition
* src/locking/lock_protocol.x: Wire protocol for virtlockd
* src/Makefile.am: Include lock_protocol.[ch] in virtlockd
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virtlockd daemon will maintain locks on behalf of libvirtd.
There are two reasons for it to be separate
- Avoid risk of other libvirtd threads accidentally
releasing fcntl() locks by opening + closing a file
that is locked
- Ensure locks can be preserved across libvirtd restarts.
virtlockd will need to be able to re-exec itself while
maintaining locks. This is simpler to achieve if its
sole job is maintaining locks
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Refactor virLockManagerPluginNew() so that the caller does
not need to pass in the config file path itself - just the
config directory and driver name.
Fix QEMU to actually pass in a config file when creating the
default lock manager plugin, rather than NULL.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It may take some time for sanlock to add a lockspace. And if user
restart libvirtd service meanwhile, the fresh daemon can fail adding
the same lockspace with EINPROGRESS. Recent sanlock has
sanlock_inq_lockspace() function which should block until lockspace
changes state. If we are building against older sanlock we should
retry a few times before claiming an error. This issue can be easily
reproduced:
for i in {1..1000} ; do echo $i; service libvirtd restart; sleep 2; done
20
Stopping libvirtd daemon: [FAILED]
Starting libvirtd daemon: [ OK ]
21
Stopping libvirtd daemon: [ OK ]
Starting libvirtd daemon: [ OK ]
22
Stopping libvirtd daemon: [ OK ]
Starting libvirtd daemon: [ OK ]
error : virLockManagerSanlockSetupLockspace:334 : Unable to add
lockspace /var/lib/libvirt/sanlock/__LIBVIRT__DISKS__: Operation now in
progress
The libvirt coding standard is to use 'function(...args...)'
instead of 'function (...args...)'. A non-trivial number of
places did not follow this rule and are fixed in this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
libvirt started using sanlock_killpath to implement on_lockfailure
action. Since sanlock_killpath was introduced in sanlock 2.4, libvirt
fails to build with older sanlock.
