The virNetServerServiceNewFDOrUNIX method cannot be correctly used when
dealing with systemd activation of a service which can receive more than
one socket FD as there is not guaranteed ordering of FDs.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Currently code has to first create the service and then separately
register it with the server. If the socket associated with a particular
service is not passed from systemd we want to skip creating the service
altogether. This means we can't put the systemd activation logic into
the constructors for virNetServerService.
This patch thus creates some helper methods against virNetServer which
combine systemd activation, service creation and service registration
into one single operation. This operation is automatically a no-op if
systemd activation is present and no sockets were passed in.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The virNetServerServiceNewFD API only accepts a single FD, but it is
easily changed to allow for an array of FDs to be passed in.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Libvirtd has long had integration with avahi for advertising libvirtd
using mDNS when TCP/TLS listening is enabled. For a long time the
virt-manager application had support for auto-detecting libvirtds
on the local network using mDNS, but this was removed last year
commit fc8f8d5d7e3ba80a0771df19cf20e84a05ed2422
Author: Cole Robinson <crobinso@redhat.com>
Date: Sat Oct 6 20:55:31 2018 -0400
connect: Drop avahi support
Libvirtd can advertise itself over avahi. The feature is disabled by
default though and in practice I hear of no one actually using it
and frankly I don't think it's all that useful
The 'Open Connection' wizard has a disproportionate amount of code
devoted to this feature, but I don't think it's useful or worth
maintaining, so let's drop it
I've never heard of any other applications having support for using
mDNS to detect libvirtd instances. Though it is theoretically possible
something exists out there, it is clearly going to be a niche use case
in the virt ecosystem as a whole.
By removing avahi integration we can cut down the dependency chain for
the basic libvirtd install and reduce our code maint burden.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Various binaries are statically linking to libvirt_util.la and
other intermediate libraries we build. These intermediate libs
all get built into the main libvirt.so shared library eventually,
so we can dynamically link to that instead and reduce the on disk
footprint.
In libvirt-daemon RPM:
virtlockd: 1.6 MB -> 153 KB
virtlogd: 1.6 MB -> 157 KB
libvirt_iohelper: 937 KB -> 23 KB
In libvirt-daemon-driver-network RPM:
libvirt_leaseshelper: 940 KB -> 26 KB
In libvirt-daemon-driver-storage-core RPM:
libvirt_parthelper: 926 KB -> 21 KB
IOW, about 5.6 MB total space saving in a build done on Fedora 30
x86_64 architecture.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Checking virNetClientStreamRaiseError without client lock
is racy which is fixed in [1] for example. Thus let's remove such checks
when we are sending message to server. And in other cases
(like virNetClientStreamRecvHole for example) let's move the check
into client stream code.
virNetClientStreamRecvPacket already have stream lock so we could
introduce another error checking function like virNetClientStreamRaiseErrorLocked
but as error is set when both client and stream lock are hold we
can remove locking from virNetClientStreamRaiseError because all
callers hold either client or stream lock.
Also let's split virNetClientStreamRaiseErrorLocked into checking
state function and checking message send status function. They are
same yet.
[1] 1b6a29c21: rpc: fix race on stream abort/finish and server side abort
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
In next patches we'll add stream state checks to this
function that applicable to all call paths. This is handy
place because we hold client lock here.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Now that GnuTLS is required these symbols are going to be present
all the time.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Since GnuTLS is required there is no way to go with !WITH_GNUTLS
branch and just distribute these files.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The Win32 symbol export file format can't do wildcards, so none of
the 'xdr_*' symbols are exported from the libvirt DLL. This doesn't
matter generally since the RPC client is built into the DLL and we
don't build libvirtd on Win32. The virnetmessagetest, however, does
require xdr_virNetMessageError to be exported, so just do a hack for
that.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The libvirt_driver_remote.la static library is linked into the
libvirt.so dynamic library, providing both the generic RPC layer code
and the remote protocol client driver. The libvirtd daemon the itself
links to libvirt_driver_remote.la, in order to get access to the generic
RPC layer code and the XDR functions for the remote driver. This means
we get multiple copies of the same code in libvirtd, one direct and one
indirect via libvirt.so. The same mistake affects the lockd plugin.
The libvirtd daemon should instead just link aganist the generic RPC
layer code that's in libvirt.so. This is easily doable if we add exports
for the few symbols we've previously missed, and wildcard export xdr_*
to expose the auto-generated XDR marshallers.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
With the current code it is neccessary to call
virNetDaemonNewPostExecRestart()
and then for each server that needs restarting you are supposed
to call
virNetDaemonAddSeverPostExecRestart()
This is fine if there's only ever one server, but as soon as you
have two servers it is impossible to use this design. The code
has no idea which servers were recorded in the JSON state doc,
nor in which order the hash table serialized its keys.
So this patch changes things so that we only call
virNetDaemonNewPostExecRestart()
passing in a callback, which is invoked once for each server
found int he JSON state doc.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It is not possible to blindly call virNetDaemonGetServer()
because in a post-exec restart scenario, some servers may
not exist and this method will pollute the error logs.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Replace virNetServerClientNeedAuth with
virNetServerClientIsAuthenticated because it makes it clearer what it
means.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
'Squash' virNetServerClientNeedAuthLocked into
virNetServerClientNeedAuth and remove virNetServerClientNeedAuthLocked
as it's not longer needed.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
There is a race between virNetServerProcessClients (main thread) and
remoteDispatchAuthList/remoteDispatchAuthPolkit/remoteSASLFinish (worker
thread) that can lead to decrementing srv->nclients_unauth when it's
zero. Since virNetServerCheckLimits relies on the value
srv->nclients_unauth the underrun causes libvirtd to stop accepting
new connections forever.
Example race scenario (assuming libvirtd is using policykit and the
client is privileged):
1. The client calls the RPC remoteDispatchAuthList =>
remoteDispatchAuthList is executed on a worker thread (Thread
T1). We're assuming now the execution stops for some time before
the line 'virNetServerClientSetAuth(client, 0)'
2. The client closes the connection irregularly. This causes the
event loop to wake up and virNetServerProcessClient to be
called (on the main thread T0). During the
virNetServerProcessClients the srv lock is hold. The condition
virNetServerClientNeedAuth(client) will be checked and as the
authentication is not finished right now
virNetServerTrackCompletedAuthLocked(srv) will be called =>
--srv->nclients_unauth => 0
3. The Thread T1 continues, marks the client as authenticated, and
calls virNetServerTrackCompletedAuthLocked(srv) =>
--srv->nclients_unauth => --0 => wrap around as nclient_unauth is
unsigned
4. virNetServerCheckLimits(srv) will disable the services forever
To fix it, add an auth_pending field to the client struct so that it
is now possible to determine if the authentication process has already
been handled for this client.
Setting the authentication method to none for the client in
virNetServerProcessClients is not a proper way to indicate that the
counter has been decremented, as this would imply that the client is
authenticated.
Additionally, adjust the existing test cases for this new field.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Combine virNetServerClientSetAuth(client,
VIR_NET_SERVER_SERVICE_AUTH_NONE) and virNetServerTrackCompletedAuth
into one new function named virNetServerSetClientAuthenticated.
After using this new function the function
virNetServerTrackCompletedAuth was superfluous and is therefore
removed. In addition, it is not very common that a
'{{function}}' (virNetServerTrackCompletedAuth) does more than just
the locking compared to
'{{function}}Locked' (virNetServerTrackCompletedAuthLocked).
virNetServerTrackPendingAuth was already superfluous and therefore
it's also removed.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The lock for @client must not only be held for the duration of
checking whether the client wants to close, but also for as long as
we're closing the client. The same applies to the tracking of
authentications.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Be more precise in which cases the authentication is needed and
introduce *Locked.
Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: Stefan Zimmermann <stzi@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Prior to this change, we relied solely on the inherited readonly
attribute of a service's socket. This only worked for our UNIX sockets
(and only to some degree), but doesn't work for TCP sockets which are RW
by default, but such connections support RO as well. This patch forces
an update on the client object once we have established a connection to
reflect the nature of the connection itself rather than relying on the
underlying socket's attributes.
Clients connected to the admin server have always been connected as RW
only.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1524399
Signed-off-by: Erik Skultety <eskultet@redhat.com>
While the previous commit implemented a helper for sending a
STREAM_HOLE packet for daemon, this is a client's counterpart.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This is just a helper function that takes in a length value,
encodes it into XDR and sends to client.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Use it in virNetServerClientGetInfo to switch back to using
the URI-format (separated by ':') instead of the SASL format
(separated by ';').
Also use it in the error message reported by virNetServerAddClient.
Add some trivial getters for client related attributes to virnetserver before
any admin method can be introduced.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
This removes the opencoded payload freeing in the client, to use
the shared virNetMessageClearPayload call. Two changes:
- ClearPayload sets nfds=0, which fixes a potential crash if
an error path called virNetMessageFree/Clear on the message
after fds was free'd
- We drop the inner loop VIR_FORCE_CLOSE... this may mean fds are
kept open a little bit longer if the call is blocking but in
practice I don't think it will have any effect
This method just aggregates various client object attributes, like socket
address, connection type (RO/RW), and some TCP/TLS/UNIX identity in an atomic
manner.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Although we document 6 types of transport that we support, internally we can
only differentiate between TCP, TLS, and UNIX transports only, since both SSH
and libssh2 transports, due to using netcat, behave in the exactly the same
way as a UNIX socket.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
For now, the list copy is done simply by locking the whole server, walking the
original and increasing the refcount on each object. We may want to change
the list to a lockable object (like list of domains) later in the future if
we discover some performance issues related to locking the whole server in
order to walk the whole list of clients, possibly issuing some 'ForEach'
callback.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Admin API needs a way of addressing specific clients. Unlike servers, which we
are happy to address by names both because its name reflects its purpose (to
some extent) and we only have two of them (so far), naming clients doesn't make
any sense, since a) each client is an anonymous, i.e. not recognized after a
disconnect followed by a reconnect, b) we can't predict what kind of requests
it's going to send to daemon, and c) the are loads of them comming and going,
so the only viable option is to use an ID which is of a reasonably wide data
type.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
For now it does not matter which ones we return as the code is similarly
complex, however it will fit in with other constructs in the future,
mainly when we will be able to generate dispatch helpers.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Since its introduction in 2011 (particularly in commit f4324e3292),
the option doesn't work. It just effectively disables all incoming
connections. That's because the client private data that contain the
'keepalive_supported' boolean, are initialized to zeroes so the bool is
false and the only other place where the bool is used is when checking
whether the client supports keepalive. Thus, according to the server,
no client supports keepalive.
Removing this instead of fixing it is better because a) apparently
nobody ever tried it since 2011 (4 years without one month) and b) we
cannot know whether the client supports keepalive until we get a ping or
pong keepalive packet. And that won't happen until after we dispatched
the ConnectOpen call.
Another two reasons would be c) the keepalive_required was tracked on
the server level, but keepalive_supported was in private data of the
client as well as the check that was made in the remote layer, thus
making all other instances of virNetServer miss this feature unless they
all implemented it for themselves and d) we can always add it back in
case there is a request and a use-case for it.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
This function accesses the number of connected clients while properly
locking the server it returns the data about.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
The socket test suite has a function for checking if IPv4
or IPv6 are available, and returning a free socket. The
first bit of that will be needed in another test, so pull
that logic out into a separate helper method.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
It's just a wrapper around NewFD and NewUNIX that selects the right
option and increments the number of used FDs.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
I tried to test ./configure --without-lxc --without-remote.
First, the build failed with some odd errors, such as an
inability to build xen, or link failures for virNetTLSInit.
But when you think about it, once there is no remote code,
all of libvirtd is useless, any stateful driver that depends
on libvirtd is also not worth compiling, and any libraries
used only by RPC code are not needed. So I patched
configure.ac to make for some saner defaults when an
explicit disable is attempted. Similarly, since we have
migrated virnetdevbridge into generic code, the workaround
for Linux kernel stupidity must not depend on stateful
drivers being in use.
Then there's 'make check' that needs segregation.
Wow - quite a bit of cleanup to make --without-remote useful :)
* configure.ac: Let --without-remote toggle defaults on stateful
drivers and other libraries. Pick up Linux kernel workarounds
even when qemu and lxc are not being compiled.
* tests/Makefile.am (test_programs): Factor out programs that
require remote.
* src/libvirt_private.syms (rpc/virnet*.h): Move...
* src/libvirt_remote.syms: ...into new file.
* src/Makefile.am (SYM_FILES): Ship new syms file.
Signed-off-by: Eric Blake <eblake@redhat.com>
