Prior to commit 2737aaaf, we allowed every client to connect successfully,
however, if accepting a client would eventually lead to an overcommit of the
limits, we would disconnect it immediately with "Too many active clients,
dropping connection from...". Recent changes refactored the code in a way, that
it is not possible for the client-related callback to be dispatched and the
client to be accepted if the limits wouldn't permit to do so, therefore a check
if a connection should be dropped due to limits violation has become a dead
code that could be removed.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Commit 2737aaaf changed our policy for accepting new clients in a way, that
instead of accepting new clients only to disconnect them immediately, since
that would overcommit the limit, we temporarily disable polling for the
dedicated file descriptor, so any new connection will queue on the socket.
Commit 8b1f0469 then added the possibility to change the limits during runtime
but it didn't re-enable polling for the previously disabled file descriptor,
thus any new connection would still continue to queue on the socket. This patch
forces an update of the services each time the limits were changed in some way.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1357776
Signed-off-by: Erik Skultety <eskultet@redhat.com>
So far, virNetServerCheckLimits was only used to possibly re-enable accepting
new clients that might have previously been disabled due to client limits
violation (max_clients, max_anonymous_clients). This patch refactors
virNetServerAddClient, which is currently the only place where the services get
disabled, in order to use the virNetServerCheckLimits helper instead of
checking the limits by itself.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Since virNetServerAddClient checks for the limits in order to temporarily
suspend the services, thus not accepting any more clients, there is no reason
why virNetServerCheckLimits, which is only responsible for re-enabling
previously disabled services according to the limits, could not do both. To be
able to do that however, it needs to be moved up in the file since it's static
(and because it's just a helper and there's only one caller it should remain
static).
Signed-off-by: Erik Skultety <eskultet@redhat.com>
virNetServerClientGetInfo returns the client's remote address
as a string, which is a part of the client object.
Use VIR_STRDUP to make a copy which can be freely accessed
even after the virNetServerClient object is unlocked.
To reproduce, put a sleep between virObjectUnlock in
virNetServerClientGetInfo and virTypedParamsAddString in
adminClientGetInfo, then close the queried connection during
that sleep.
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.
This partially reverts commit 9b45c9f049.
It changed the default format of socket address from the one SASL
requires, but did not adjust all the callers.
It also removed the test coverage for it.
Revert most of the changes except the virSocketAddrFormatFull support
for URI-formatted strings.
This fixes https://bugzilla.redhat.com/show_bug.cgi?id=1345743 while
reverting the format used by virt-admin's client-info command from
the URI one to the SASL one.
https://bugzilla.redhat.com/show_bug.cgi?id=1345743
Since it's rather tedious to write the dispatchers for functions that
return an array of typed parameters (which are rather common) let's add
some rpcgen code to generate them.
Extend the virNetTLSContextNew* constructors to allow
the TLS priority string to be passed in, overriding the
compile time default.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently libvirt calls gnutls_set_default_priority()
which on old systems resolves to "NORMAL" while new
systems it resolves to "@SYSTEM". Either way, this
is a global default that is identical across all apps.
We want to allow distros to flexibility to define a
custom default string for libvirt priority, so add
a --tls-priority=STRING flag to configure to enable
this to be set.
It is expected that distros would use this when creating
RPM/Deb/etc packages, according to their preferred crypto
handling policies.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently we set the gnutls log function when creating a
TLS context, however, the setting is in fact global, not
per context. So we should be setting it when we first call
gnutls_global_init() instead.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
We need to use the gnutls_priority_set_direct method which
was not introduced until 2.1.7, so bump version to 2.2.0
which is the first stable release with it included. This
release dates from Dec 2007 so it is reasonable to ditch
support for the 1.x.x series for gnutls releases entirely.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Opposite operation to virAdmServerGetClientLimits. Understandably though,
setting values for current number of clients connected or still waiting
for authentication does not make sense, since changes to these values are event
dependent, i.e. a client connects - counter is increased. Thus only the limits
to maximum clients connected and waiting for authentication can be set. Should
a request for other controls to be set arrive (provided such a setting will
be first introduced to the config), the set of configuration controls can be
later expanded (thanks to typed params). This patch also introduces a
constraint that the maximum number of clients waiting for authentication has to
be less than the overall maximum number of clients connected and any attempt to
violate this constraint will be denied.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
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
I've noticed this while trying to compile libvirt on my arm box.
CC rpc/libvirt_net_rpc_server_la-virnetserverclient.lo
rpc/virnetserverclient.c: In function 'virNetServerClientNewPostExecRestart':
rpc/virnetserverclient.c:516:45: error: cast increases required alignment of target type [-Werror=cast-align]
(long long *) ×tamp) < 0) {
^
cc1: all warnings being treated as errors
Problem is, @timestap is defined as time_t which is 32 bits long,
and we are typecasting it to long long which is 64bits long.
Solution is to make @timestamp type of long long. At the same
time, we can make @conn_time in _virNetServerClient struct long
long too. There is no need for it to be type of time_t.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
In this function, @id is defined as unsigned long long. When
passing this variable to virJSONValueObjectGetNumberUlong(),
well address of this variable, it's typecasted to ull*. There
is no need for that. It's a same story with @nrequests_max.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
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>
We do have a similar method, serving the same purpose, for TLS, but we lack
one for SASL. So introduce one, in order for other modules to be able to find
out, if a SASL session is active, or better said, that a SASL session exists
at all.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Our socket address format is in a rather non-standard format and that is
because sasl library requires the IP address and service to be delimited by a
semicolon. The string form is a completely internal matter, however once the
admin interfaces to retrieve client identity information are merged, we should
return the socket address string in a common format, e.g. format defined by
URI rfc-3986, i.e. the IP address and service are delimited by a colon and
in case of an IPv6 address, square brackets are added:
Examples:
127.0.0.1:1234
[::1]:1234
This patch changes our default format to the one described above, while adding
separate methods to request the non-standard SASL format using semicolon as a
delimiter.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Just like with server-related APIs, before any of client-based APIs can be
called, a reference to a client-side client object needs to be obtained. For
this purpose, a lookup method should exist. Apart from the client retrieval
logic, a new error code for non-existent client had to be added as well.
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>
Now that libvirt-admin supports another client-side object and provided that
we want to generate as many both client-side and server-side RPC dispatchers,
support for this needs to be added to gendispatch.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Besides ID, libvirt should provide several parameters to help the user
distinguish two clients from each other. One of them is the connection
timestamp. This patch also adds a testcase for proper JSON formatting of the
new attribute too (proper formatting of older clients that did not support
this attribute yet is included in the existing tests) - in order to
testGenerateJSON to work, a mock of time_t time(time_t *timer) needed to be
created.
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>
There are two functions on the client that handle incoming stream
data. The first one virNetClientStreamQueuePacket() is a low
level function that just processes the incoming stream data from
the socket and stores it into an internal structure. This happens
in the client event loop therefore the shorter the callbacks are,
the better. The second function virNetClientStreamRecvPacket()
then handles copying data from internal structure into a client
provided buffer.
Change introduced in this commit makes just that: new queue for
incoming stream packets is introduced. Then instead of copying
data into intermediate internal buffer and then copying them into
user buffer, incoming stream messages are queue into the queue
and data is copied just once - in the upper layer function
virNetClientStreamRecvPacket(). In the end, there's just one
copying of data and therefore shorter event loop callback. This
should boost the performance which has proven to be the case in
my testing.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This reverts commit d9c9e138f2.
Unfortunately, things are going to be handled differently so this
commit must go.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
FD passing APIs like CreateXMLWithFiles or OpenGraphicsFD will leak
file descriptors. The user passes in an fd, which is dup()'d in
virNetClientProgramCall. The new fd is what is transfered to the
server virNetClientIOWriteMessage.
Once all the fds have been written though, the parent msg->fds list
is immediately free'd, so the individual fds are never closed.
This closes each FD as its send to the server, so all fds have been
closed by the time msg->fds is free'd.
https://bugzilla.redhat.com/show_bug.cgi?id=1159766
The stream serial number is the serial number of the RPC call
that initiated a data transfer. And as such can never be
negative. Moreover, when looking up internal state for a stream,
the serial numbers are compared. But hey, the serial number in
message header is unsigned too!
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Since threadpool increments the current number of threads according to current
load, i.e. how many jobs are waiting in the queue. The count however, is
constrained by max and min limits of workers. The logic of this new API works
like this:
1) setting the minimum
a) When the limit is increased, depending on the current number of
threads, new threads are possibly spawned if the current number of
threads is less than the new minimum limit
b) Decreasing the minimum limit has no possible effect on the current
number of threads
2) setting the maximum
a) Icreasing the maximum limit has no immediate effect on the current
number of threads, it only allows the threadpool to spawn more
threads when new jobs, that would otherwise end up queued, arrive.
b) Decreasing the maximum limit may affect the current number of
threads, if the current number of threads is less than the new
maximum limit. Since there may be some ongoing time-consuming jobs
that would effectively block this API from killing any threads.
Therefore, this API is asynchronous with best-effort execution,
i.e. the necessary number of workers will be terminated once they
finish their previous job, unless other workers had already
terminated, decreasing the limit to the requested value.
3) setting priority workers
- both increase and decrease in count of these workers have an
immediate impact on the current number of workers, new ones will be
spawned or some of them get terminated respectively.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
New API to retrieve current server workerpool specs. Since it uses typed
parameters, more specs to retrieve can be further included in the pool of
supported ones.
Signed-off-by: Erik Skultety <eskultet@redhat.com>
Trying to reload/SIGUSR1 virtlogd or virtlockd fails with:
error : virNetDaemonRun:747 : internal error: Not all servers restored, cannot run server
Commit 252610f7 changed the daemon state json to allow tracking
multiple servers. However it missed clearing dmn->srvObject after
the json is empty, like the previous code paths handled. Later on in
virNewDaemonRun, dmn->srvObject is expected to be empty otherwise we
throw the above error.
https://bugzilla.redhat.com/show_bug.cgi?id=1311013
fdstream.c: In function 'virFDStreamWrite':
fdstream.c:390:29: error: logical 'or' of equal expressions [-Werror=logical-op]
if (errno == EAGAIN || errno == EWOULDBLOCK) {
^~
Fedora rawhide now uses gcc 6.0 and there is a bug with -Wlogical-op
producing false warnings.
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69602
Use GCC pragma push/pop and ignore -Wlogical-op for GCC that supports
push/pop pragma and also has this bug.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Compilation for xdg-app failed due to a buggy SASL headers present on
the used runtime (org.gnome.Sdk 3.18).
In file included from rpc/virnetsaslcontext.h:24:0,
from rpc/virnetsaslcontext.c:25:
/usr/include/sasl/sasl.h:230:38: error: unknown type name 'size_t'
typedef void *sasl_realloc_t(void *, size_t);
^
/usr/include/sasl/sasl.h:235:5: error: unknown type name 'sasl_realloc_t'
sasl_realloc_t *,
Use the same workaround as commit 1be3dfd did.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
The adminDispatchConnectListServers() function is generated by
our great perl script. However, it has a tiny flaw: if
adminConnectListServers() it calls fails, the control jumps onto
cleanup label where we try to free any list of servers built so
far. However, in the loop @i is unsigned (size_t) while @nresults
is signed (int). Currently, it does no harm because of the check
for @result being non-NULL. But if that ever changes in the
future, this bug will be hard to chase.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1271183
We only wait 0.5 seconds for the session daemon to start up and present
its socket, which isn't sufficient for many users. Bump up the sleep
interval and retry amount so we wait for a total of 5.0 seconds.
