We want to convert over to server-side events, even for older
APIs. To do that, the client side of the remote driver wants
to distinguish between legacy virConnectDomainEventRegister and
normal virConnectDomainEventRegisterAny, while knowing the
client callbackID and the server's serverID for both types of
registration. The client also needs to probe whether the
server supports server-side filtering. However, for ease of
review, we don't actually use the new RPCs until a later patch.
* src/conf/object_event_private.h (virObjectEventStateCallbackID):
Add parameter.
* src/conf/object_event.c (virObjectEventCallbackListAddID)
(virObjectEventStateRegisterID): Separate legacy from callbackID.
(virObjectEventStateCallbackID): Pass through parameter.
(virObjectEventCallbackLookup): Let legacy and global domain
lifecycle events share a common remoteID.
* src/conf/network_event.c (virNetworkEventStateRegisterID):
Update caller.
* src/conf/domain_event.c (virDomainEventStateRegister)
(virDomainEventStateRegisterID, virDomainEventStateDeregister):
Likewise.
(virDomainEventStateRegisterClient)
(virDomainEventStateCallbackID): Implement new functions.
* src/conf/domain_event.h (virDomainEventStateRegisterClient)
(virDomainEventStateCallbackID): New prototypes.
* src/remote/remote_driver.c (private_data): Add field.
(doRemoteOpen): Probe server feature.
(remoteConnectDomainEventRegister)
(remoteConnectDomainEventRegisterAny): Use new function.
Signed-off-by: Eric Blake <eblake@redhat.com>
Ever since ACL filtering was added in commit 7639736 (v1.1.1), a
user could still use event registration to obtain access to a
domain that they could not normally access via virDomainLookup*
or virConnectListAllDomains and friends. We already have the
framework in the RPC generator for creating the filter, and
previous cleanup patches got us to the point that we can now
wire the filter through the entire object event stack.
Furthermore, whether or not domain:getattr is honored, use of
global events is a form of obtaining a list of networks, which
is covered by connect:search_domains added in a93cd08 (v1.1.0).
Ideally, we'd have a way to enforce connect:search_domains when
doing global registrations while omitting that check on a
per-domain registration. But this patch just unconditionally
requires connect:search_domains, even when no list could be
obtained, based on the following observations:
1. Administrators are unlikely to grant domain:getattr for one
or all domains while still denying connect:search_domains - a
user that is able to manage domains will want to be able to
manage them efficiently, but efficient management includes being
able to list the domains they can access. The idea of denying
connect:search_domains while still granting access to individual
domains is therefore not adding any real security, but just
serves as a layer of obscurity to annoy the end user.
2. In the current implementation, domain events are filtered
on the client; the server has no idea if a domain filter was
requested, and must therefore assume that all domain event
requests are global. Even if we fix the RPC protocol to
allow for server-side filtering for newer client/server combos,
making the connect:serach_domains ACL check conditional on
whether the domain argument was NULL won't benefit older clients.
Therefore, we choose to document that connect:search_domains
is a pre-requisite to any domain event management.
Network events need the same treatment, with the obvious
change of using connect:search_networks and network:getattr.
* src/access/viraccessperm.h
(VIR_ACCESS_PERM_CONNECT_SEARCH_DOMAINS)
(VIR_ACCESS_PERM_CONNECT_SEARCH_NETWORKS): Document additional
effect of the permission.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Add new parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/object_event_private.h (virObjectEventStateRegisterID):
Likewise.
* src/conf/object_event.c (_virObjectEventCallback): Track a filter.
(virObjectEventDispatchMatchCallback): Use filter.
(virObjectEventCallbackListAddID): Register filter.
* src/conf/domain_event.c (virDomainEventFilter): New function.
(virDomainEventStateRegister, virDomainEventStateRegisterID):
Adjust callers.
* src/conf/network_event.c (virNetworkEventFilter): New function.
(virNetworkEventStateRegisterID): Adjust caller.
* src/remote/remote_protocol.x
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER)
(REMOTE_PROC_CONNECT_DOMAIN_EVENT_REGISTER_ANY)
(REMOTE_PROC_CONNECT_NETWORK_EVENT_REGISTER_ANY): Generate a
filter, and require connect:search_domains instead of weaker
connect:read.
* src/test/test_driver.c (testConnectDomainEventRegister)
(testConnectDomainEventRegisterAny)
(testConnectNetworkEventRegisterAny): Update callers.
* src/remote/remote_driver.c (remoteConnectDomainEventRegister)
(remoteConnectDomainEventRegisterAny): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister)
(xenUnifiedConnectDomainEventRegisterAny): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainGetXMLDesc): Likewise.
* src/libxl/libxl_driver.c (libxlConnectDomainEventRegister)
(libxlConnectDomainEventRegisterAny): Likewise.
* src/qemu/qemu_driver.c (qemuConnectDomainEventRegister)
(qemuConnectDomainEventRegisterAny): Likewise.
* src/uml/uml_driver.c (umlConnectDomainEventRegister)
(umlConnectDomainEventRegisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventRegisterAny): Likewise.
* src/lxc/lxc_driver.c (lxcConnectDomainEventRegister)
(lxcConnectDomainEventRegisterAny): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
In order to mirror a server with per-object filtering, the client
needs to track which server callbackID is servicing the client
callback. This patch introduces the notion of a serverID, as
well as the plumbing to use it for network events, although the
actual complexity of using per-object filtering in the remote
driver is deferred to a later patch.
* src/conf/object_event.h (virObjectEventStateEventID): Add parameter.
(virObjectEventStateQueueRemote, virObjectEventStateSetRemote):
New prototypes.
(virObjectEventStateRegisterID): Move...
* src/conf/object_event_private.h: ...here, and add parameter.
(_virObjectEvent): Add field.
* src/conf/network_event.h (virNetworkEventStateRegisterClient): New
prototype.
* src/conf/object_event.c (_virObjectEventCallback): Add field.
(virObjectEventStateSetRemote): New function.
(virObjectEventStateQueue): Make wrapper around...
(virObjectEventStateQueueRemote): New function.
(virObjectEventCallbackListCount): Tweak return count when remote
id matching is used.
(virObjectEventCallbackLookup, virObjectEventStateRegisterID):
Tweak registration when remote id matching will be used.
(virObjectEventNew): Default to no remote id.
(virObjectEventCallbackListAddID): Likewise, but set remote id
when one is available.
(virObjectEventCallbackListRemoveID)
(virObjectEventCallbackListMarkDeleteID): Adjust return value when
remote id was set.
(virObjectEventStateEventID): Query existing id.
(virObjectEventDispatchMatchCallback): Require matching event id.
(virObjectEventStateCallbackID): Adjust caller.
* src/conf/network_event.c (virNetworkEventStateRegisterClient): New
function.
(virNetworkEventStateRegisterID): Update caller.
* src/conf/domain_event.c (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Update callers.
* src/remote/remote_driver.c
(remoteConnectNetworkEventRegisterAny)
(remoteConnectNetworkEventDeregisterAny)
(remoteConnectDomainEventDeregisterAny): Likewise.
(remoteEventQueue): Hoist earlier to avoid forward declaration,
and add parameter. Adjust all callers.
* src/libvirt_private.syms (conf/object_event.h): Drop function.
Signed-off-by: Eric Blake <eblake@redhat.com>
If a user registers for a domain event filtered to a particular
domain, but the persistent domain is offline at the time, then
the code silently failed to set up the filter. As a result,
the event fires for all domains, rather than being filtered.
Network events were immune, since they always passed an id
0 argument.
The key to this patch is realizing that
virObjectEventDispatchMatchCallback() only cared about uuid;
so refusing to create a meta for a negative id is pointless,
and in fact, malloc'ing meta at all was overkill; instead,
just directly store a uuid and a flag of whether to filter.
Note that virObjectEventPtr still needs all fields of meta,
because this is how we reconstruct a virDomainPtr inside the
dispatch handler before calling the end user's callback
pointer with the correct object, even though only the uuid
portion of meta is used in deciding whether a callback
matches the given event. So while uuid is optional for
callbacks, it is mandatory for events.
The change to testDomainCreateXMLMixed is merely on the setup
scenario (as you can't register for a domain unless it is either
running or persistent). I actually first wrote that test for
this patch, then rebased it to also cover a prior patch (commit
4221d64), but had to adjust it for that patch to use Create
instead of Define for setting up the domain long enough to
register the event in order to work around this bug. But while
the setup is changed, the main body of the test is still about
whether creation events fire as expected.
* src/conf/object_event_private.h (_virObjectEventCallback):
Replace meta with uuid and flag.
(virObjectEventCallbackListAddID): Update signature.
* src/conf/object_event.h (virObjectEventStateRegisterID):
Likewise.
* src/conf/object_event_private.h (virObjectEventNew): Document
use of name and uuid in events.
* src/conf/object_event.c (virObjectEventCallbackListAddID): Drop
arguments that don't affect filtering.
(virObjectEventCallbackListRemoveID)
(virObjectEventDispatchMatchCallback)
(virObjectEventStateRegisterID): Update clients.
* src/conf/domain_event.c (virDomainEventCallbackListAdd)
(virDomainEventStateRegisterID): Likewise.
* src/conf/network_event.c (virNetworkEventStateRegisterID):
Likewise.
* tests/objecteventtest.c (testDomainCreateXMLMixed): Enhance test.
Signed-off-by: Eric Blake <eblake@redhat.com>
Tighten up scope after the previous patch avoided using
internals. This will also make it easier to change
internal implementation without having to chase down quite
as many impacted callers or worrying about two files getting
implementations out of sync.
* src/conf/object_event_private.h
(virObjectEventCallbackListAddID, virObjectEventQueueClear)
(virObjectEventStateLock, virObjectEventStateUnlock)
(virObjectEventTimer): Drop prototype.
(_virObjectEventCallbackList, _virObjectEventState)
(_virObjectEventCallback): Move...
* src/conf/object_event.c: ...here.
(virObjectEventCallbackListAddID, virObjectEventQueueClear)
(virObjectEventStateLock, virObjectEventStateUnlock)
(virObjectEventTimer): Mark private.
Signed-off-by: Eric Blake <eblake@redhat.com>
Right now, the older virConnectDomainEventRegister (takes a
function pointer, returns 0 on success) and the newer
virConnectDomainEventRegisterID (takes an eventID, returns a
callbackID) share the underlying implementation (the older
API ends up consuming a callbackID for eventID 0 under the
hood). We implemented that by a lot of copy and pasted
code between object_event.c and domain_event.c, according to
whether we are dealing with a function pointer or an eventID.
However, our copy and paste is not symmetric. Consider this
sequence:
id1 = virConnectDomainEventRegisterAny(conn, dom,
VIR_DOMAIN_EVENT_ID_LIFECYCLE,
VIR_DOMAIN_EVENT_CALLBACK(callback), NULL, NULL);
virConnectDomainEventRegister(conn, callback, NULL, NULL);
virConnectDomainEventDeregister(conn, callback);
virConnectDomainEventDeregsiterAny(conn, id1);
the first three calls would succeed, but the third call ended
up nuking the id1 callbackID (the per-domain new-style handler),
then the fourth call failed with an error about an unknown
callbackID, leaving us with the global handler (old-style) still
live and receiving events. It required another old-style
deregister to clean up the mess. Root cause was that
virDomainEventCallbackList{Remove,MarkDelete} were only
checking for function pointer match, rather than also checking
for whether the registration was global.
Rather than playing with the guts of object_event ourselves
in domain_event, it is nicer to add a mapping function for the
internal callback id, then share common code for event removal.
For now, the function-to-id mapping is used only internally;
I thought about whether a new public API to let a user learn
the callback would be useful, but decided exposing this to the
user is probably a disservice, since we already publicly
document that they should avoid the old style, and since this
patch already demonstrates that older libvirt versions have
weird behavior when mixing old and new styles.
And like all good bug fix patches, I enhanced the testsuite,
validating that the changes in tests/ expose the failure
without the rest of the patch.
* src/conf/object_event.c (virObjectEventCallbackLookup)
(virObjectEventStateCallbackID): New functions.
(virObjectEventCallbackLookup): Use helper function.
* src/conf/object_event_private.h (virObjectEventStateCallbackID):
Declare new function.
* src/conf/domain_event.c (virDomainEventStateRegister)
(virDomainEventStateDeregister): Let common code handle the
complexity.
(virDomainEventCallbackListRemove)
(virDomainEventCallbackListMarkDelete)
(virDomainEventCallbackListAdd): Drop unused functions.
* tests/objecteventtest.c (testDomainCreateXMLMixed): New test.
Signed-off-by: Eric Blake <eblake@redhat.com>
We might as well take advantage of viralloc.h instead of open-coding
array management ourselves. While at it, I simplified several
places that were doing repetitive pointer chasing to use an
intermediate variable for legibility (some other places remain,
but they will disapper in later refactoring patches).
* src/conf/object_event_private.h (_virObjectEventCallbackList):
Use size_t for count.
* src/conf/object_event.c (_virObjectEventQueue): Likewise.
(virObjectEventCallbackListRemoveID): Use VIR_DELETE_ELEMENT.
(virObjectEventQueuePush, virObjectEventCallbackListAddID): Use
VIR_APPEND_ELEMENT.
(virObjectEventCallbackListEventID)
(virObjectEventStateDispatchCallbacks): Simplify code.
Signed-off-by: Eric Blake <eblake@redhat.com>
No need to use an int that only ever stores 0 and 1.
* src/conf/object_event_private.h (_virObjectEventCallback):
Change deleted to bool.
* src/conf/object_event.c (virObjectEventDispatchMatchCallback):
Switch return type to bool.
(virObjectEventCallbackListMarkDeleteID): Update client.
* src/conf/domain_event.c (virDomainEventCallbackListMarkDelete):
Likewise.
Any file with access to object_event_private.h also has access to
the internals of virObjectEvent, without needing an accessor
function. Not to mention the accessor function was doing type
checks that would always succeed.
* src/conf/object_event_private.h (virObjectEventGetEventID): Drop.
* src/conf/object_event.c (virObjectEventGetEventID): Drop.
(virObjectEventDispatchMatchCallback): Simplify caller.
* src/conf/domain_event.c (virDomainEventDispatchDefaultFunc):
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
The event namespace concept is mostly redundant information.
With the re-written dispatcher, the namespace is only used
for equality comparisons between event IDs. This can be solved
by just comparing virClassPtr instances instead.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of having the object event code have to know about each
type of event and their dispatch functions, associate a dispatch
function with the object instance. The dispatch code can thus be
significantly simplified.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
