https://bugzilla.redhat.com/show_bug.cgi?id=1055484

Currently, libvirt's XML schema of network allows QoS to be defined for
every network even though it has no bridge. For instance:

<network>
    <name>vdsm-no-bridge</name>
    <forward mode='passthrough'>
      <interface dev='em1.10'/>
    </forward>
    <bandwidth>
        <inbound average='1000' peak='5000' burst='1024'/>
        <outbound average='1000' burst='1024'/>
    </bandwidth>
</network>

The bandwidth limitations can be, however, applied even on such
networks. In fact, they are going to be applied on the interface that
will be connected to the network on a domain startup. This approach,
however, has one limitation. With bridged networks, there are two points
where QoS can be set: bridge and domain interface. The lower limit of
the two is enforced then. For instance, if the interface has 10Mbps
average, but the network only 1Mbps, there's no way for interface to
transmit packets faster than the 1Mbps limit. With two points this is
enforced by kernel.  With only one point, we must combine both QoS
settings into one which is set afterwards. Look at
virNetDevBandwidthMinimal() and you'll understand immediately what I
mean.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Ever since ACL filtering was added in commit 76397360 (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 a93cd08f (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: NEric Blake <eblake@redhat.com>

While comparing network and domain events, I noticed that the
test driver had to do a cast in one place and not the other.
For consistency, we should hide the necessary casting as low
as possible in the stack, with everything else using saner
types.

* src/conf/network_event.h (virNetworkEventStateRegisterID): Alter
type.
* src/conf/network_event.c (virNetworkEventStateRegisterID): Hoist
cast here.
* src/test/test_driver.c (testConnectNetworkEventRegisterAny):
Simplify callers.
* src/remote/remote_driver.c
(remoteConnectNetworkEventRegisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventRegisterAny): Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Ever since their introduction (commit 1509b802 in v0.5.0 for
virConnectDomainEventRegister, commit 44457238 in v0.8.0 for
virConnectDomainEventDeregisterAny), the event deregistration
functions have been documented as returning 0 on success;
likewise for older registration (only the newer RegisterAny
must return a non-zero callbackID).  And now that we are
adding virConnectNetworkEventDeregisterAny for v1.2.1, it
should have the same semantics.

Fortunately, all of the stateful drivers have been obeying
the docs and returning 0, thanks to the way the remote_driver
tracks things (in fact, the RPC wire protocol is unable to
send a return value for DomainEventRegisterAny, at least not
without adding a new RPC number).  Well, except for vbox,
which was always failing deregistration, due to failure to
set the return value to anything besides its initial -1.

But for local drivers, such as test:///default, we've been
returning non-zero numbers; worse, the non-zero numbers have
differed over time.  For example, in Fedora 12 (libvirt 0.8.2),
calling Register twice would return 0 and 1 [the callbackID
generated under the hood]; while in Fedora 20 (libvirt 1.1.3),
it returns 1 and 2 [the number of callbacks registered for
that event type].  Since we have changed the behavior over
time, and since it differs by local vs. remote, we can safely
argue that no one could have been reasonably relying on any
particular behavior, so we might as well obey the docs, as well
as prepare callers that might deal with older clients to not be
surprised if the docs are not strictly followed.

For consistency, this patch fixes the code for all drivers,
even though it only makes an impact for vbox and for local
drivers.  By fixing all drivers, future copy and paste from
a remote driver to a local driver is less likely to
reintroduce the bug.

Finally, update the testsuite to gain some coverage of the
issue for local drivers, including the first test of old-style
domain event registration via function pointer instead of
event id.

* src/libvirt.c (virConnectDomainEventRegister)
(virConnectDomainEventDeregister)
(virConnectDomainEventDeregisterAny): Clarify docs.
* src/libxl/libxl_driver.c (libxlConnectDomainEventRegister)
(libxlConnectDomainEventDeregister)
(libxlConnectDomainEventDeregisterAny): Match documentation.
* src/lxc/lxc_driver.c (lxcConnectDomainEventRegister)
(lxcConnectDomainEventDeregister)
(lxcConnectDomainEventDeregisterAny): Likewise.
* src/test/test_driver.c (testConnectDomainEventRegister)
(testConnectDomainEventDeregister)
(testConnectDomainEventDeregisterAny)
(testConnectNetworkEventDeregisterAny): Likewise.
* src/uml/uml_driver.c (umlConnectDomainEventRegister)
(umlConnectDomainEventDeregister)
(umlConnectDomainEventDeregisterAny): Likewise.
* src/vbox/vbox_tmpl.c (vboxConnectDomainEventRegister)
(vboxConnectDomainEventDeregister)
(vboxConnectDomainEventDeregisterAny): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectDomainEventRegister)
(xenUnifiedConnectDomainEventDeregister)
(xenUnifiedConnectDomainEventDeregisterAny): Likewise.
* src/network/bridge_driver.c
(networkConnectNetworkEventDeregisterAny): Likewise.
* tests/objecteventtest.c (testDomainCreateXMLOld): New test.
(mymain): Run it.
(testDomainCreateXML): Check return values.
Signed-off-by: NEric Blake <eblake@redhat.com>

While the public API & wire protocol included the 'detail'
arg for network lifecycle events, the internal event handling
code did not process it. This meant that if a future libvirtd
server starts sending non-0 'detail' args, the current libvirt
client will not process them.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The networkRegister() didn't check the return status of the
virRegisterNetworkDriver() call like other callers, so just
check and handle here as well.

This patch resolves:

  https://bugzilla.redhat.com/show_bug.cgi?id=1035336

The basic problem is that during a network update, the required
iptables rules sometimes change, and this was being handled by simply
removing and re-adding the rules. However, the removal of the old
rules was done based on the *new* state of the network, which would
mean that some of the rules would not match those currently in the
system, so the old rules wouldn't be removed.

This patch removes the old rules prior to updating the network
definition then adds the new rules as soon as the definition is
updated. Note that this could lead to a stray packet or two during the
interim, but that was already a problem before (the period of limbo is
now just slightly longer).

While moving the location for the rules, I added a few more sections
that should result in the iptables rules being redone:

DHCP_RANGE and DHCP_HOST - these are needed because adding/removing a dhcp
host entry could lead to the dhcp service being started/stopped, which
would require that the mangle rule that fixes up dhcp response
checksums sould need to be added/removed, and this wasn't being done.

Most of our code base uses space after comma but not before;
fix the remaining uses before adding a syntax check.

* src/network/bridge_driver.c: Consistently use commas.
* src/node_device/node_device_hal.c: Likewise.
* src/node_device/node_device_udev.c: Likewise.
* src/storage/storage_backend_rbd.c: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This is a prerequisite to the fix for the fix to:

  https://bugzilla.redhat.com/show_bug.cgi?id=1025397

num_virtual_functions needs to be size_t in order to use the
VIR_APPEND_ELEMENT macro.

This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1020135

If networkAllocateActualDevice() had failed due to a pool of hostdev
or direct devices being depleted, the calling function could still
call networkReleaseActualDevice() as part of its cleanup, and that
function would then unconditionally decrement the connections count
for the network, even though it hadn't been incremented (due to
failure of allocate). This *was* necessary because the .actual member
of the netdef was allocated with a "lazy" algorithm, only being
created if there was a need to store data there (e.g. if a device was
allocated from a pool, or bandwidth was allocated for the device), so
there was no simple way for networkReleaseActualDevice() to tell if
something really had been allocated (i.e. if "connections++" had been
executed).

This patch changes networkAllocateDevice() to *always* allocate an
actual device for any netdef of type='network', even if it isn't
needed for any other reason. This has no ill effects anywhere else in
the code (except for using a small amount of memory), and
networkReleaseActualDevice() can then determine if there was a
previous successful allocate by checking for .actual != NULL (if not,
it skips the "connections--").

Currently, we ignore whether dnsmasqCapsRefresh succeeds or fails. We
shouldn't do that as we may generate wrong dnsmasq command line (what
is done just a few lines below).
Signed-off-by: NHongwei Bi <hwbi2008@gmail.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Useful to set custom forwarders instead of using the contents of
/etc/resolv.conf. It helps me to setup dnsmasq as local nameserver to
resolve VM domain names from domain 0, when domain option is used.
Signed-off-by: NDiego Woitasen <diego.woitasen@vhgroup.net>
Signed-off-by: NEric Blake <eblake@redhat.com>

Similarly to qemu_driver.c, we can join often repeating code of looking
up network into one function: networkObjFromNetwork.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Implement networkEnableIpForwarding() using BSD style sysctl.

This resolves the issue that prompted the filing of

  https://bugzilla.redhat.com/show_bug.cgi?id=928638

(although the request there is for something much larger and more
general than this patch).

commit f3868259 disabled the
forwarding to upstream DNS servers of unresolved DNS requests for
names that had no domain, but were just simple host names (no "."
character anywhere in the name). While this behavior is frowned upon
by DNS root servers (that's why it was changed in libvirt), it is
convenient in some cases, and since dnsmasq can be configured to allow
it, it must not be strictly forbidden.

This patch restores the old behavior, but since it is usually
undesirable, restoring it requires specification of a new option in
the network config. Adding the attribute "forwardPlainNames='yes'" to
the <dns> elemnt does the trick - when that attribute is added to a
network config, any simple hostnames that can't be resolved by the
network's dnsmasq instance will be forwarded to the DNS servers listed
in the host's /etc/resolv.conf for an attempt at resolution (just as
any FQDN would be forwarded).

When that attribute *isn't* specified, unresolved simple names will
*not* be forwarded to the upstream DNS server - this is the default
behavior.

* Move platform specific things (e.g. firewalling and route
  collision checks) into bridge_driver_platform
* Create two platform specific implementations:
    - bridge_driver_linux: Linux implementation using iptables,
      it's actually the code moved from bridge_driver.c
    - bridge_driver_nop: dumb implementation that does nothing
Signed-off-by: NEric Blake <eblake@redhat.com>

Adjust these drivers to handle their Autostart functionality after each
of the drivers has gone through their Initialization functions

Continue preparation for extracting platform-specific
parts from bridge_driver: s/Iptables/Firewall/ for
firewall related function names.

This is another cleanup before extracting platform-specific
parts from bridge_driver.

Rename struct network_driver to _virNetworkDriverState and
add appropriate typedefs: virNetworkDriverState and
virNetworkDriverStatePtr.

This will help us to avoid potential problems when moving
this struct to the .h file.

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: NDaniel P. Berrange <berrange@redhat.com>

Ensure that all APIs which list network objects filter
them against the access control system.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

iptablesContext holds only 4 pairs of iptables
(table, chain) and there's no need to pass
it around.

This is a first step towards separating bridge_driver.c
in platform-specific parts.

If networkUnplugBandwidth is called on a network which has
no bandwidth defined, print a warning instead of crashing.

This can happen when destroying a domain with bandwidth if
bandwidth was removed from the network after the domain was
started.

https://bugzilla.redhat.com/show_bug.cgi?id=975359

Although SRIOV network cards support setting a vlan tag on their
virtual functions, and although setting this vlan tag via a <vlan>
element in a domain's <interface> works, setting a vlan tag for these
devices in a <network> definition, or in a network <portgroup>
definition is also supposed to work (and the comment that validates
<vlan> usage even says that!). However, the check to allow it only
checked for an openvswitch network, so attempts to add <vlan> to a
network of type='hostdev' would fail.

Insert calls to the ACL checking APIs in all network driver
entrypoints.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This fixes the problem reported in:

   https://bugzilla.redhat.com/show_bug.cgi?id=972690

When checking for a collision of a new libvirt network's subnet with
any existing routes, we read all of /proc/net/route into memory, then
parse all the entries. The function that we use to read this file
requires a "maximum length" parameter, which had previously been set
to 64*1024. As each line in /proc/net/route is 128 bytes, this would
allow for a maximum of 512 entries in the routing table.

This patch increases that number to 128 * 100000, which allows for
100,000 routing table entries. This means that it's possible that 12MB
would be allocated, but that would only happen if there really were
100,000 route table entries on the system, it's only held for a very
short time.

Since there is no method of specifying and unlimited max (and that
would create a potential denial of service anyway) hopefully this
limit is large enough to accomodate everyone.

In order to learn libvirt multiqueue several things must be done:

1) The '/dev/net/tun' device needs to be opened multiple times with
IFF_MULTI_QUEUE flag passed to ioctl(fd, TUNSETIFF, &ifr);

2) Similarly, '/dev/vhost-net' must be opened as many times as in 1)
in order to keep 1:1 ratio recommended by qemu and kernel folks.

3) The command line construction code needs to switch from 'fd=X' to
'fds=X:Y:...:Z' and from 'vhostfd=X' to 'vhostfds=X:Y:...:Z'.

4) The monitor handling code needs to learn to pass multiple FDs.

network: static route support for <network>

This patch adds the <route> subelement of <network> to define a static
route.  the address and prefix (or netmask) attribute identify the
destination network, and the gateway attribute specifies the next hop
address (which must be directly reachable from the containing
<network>) which is to receive the packets destined for
"address/(prefix|netmask)".

These attributes are translated into an "ip route add" command that is
executed when the network is started. The command used is of the
following form:

  ip route add <address>/<prefix> via <gateway> \
               dev <virbr-bridge> proto static metric <metric>

Tests are done to validate that the input data are correct.  For
example, for a static route ip definition, the address must be a
network address and not a host address.  Additional checks are added
to ensure that the specified gateway is directly reachable via this
network (i.e. that the gateway IP address is in the same subnet as one
of the IP's defined for the network).

prefix='0' is supported for both family='ipv4' address='0.0.0.0'
netmask='0.0.0.0' or prefix='0', and for family='ipv6' address='::',
prefix=0', although care should be taken to not override a desired
system default route.

Anytime an attempt is made to define a static route which *exactly*
duplicates an existing static route (for example, address=::,
prefix=0, metric=1), the following error message will be sent to
syslog:

    RTNETLINK answers: File exists

This can be overridden by decreasing the metric value for the route
that should be preferred, or increasing the metric for the route that
shouldn't be preferred (and is thus in place only in anticipation that
the preferred route may be removed in the future).  Caution should be
used when manipulating route metrics, especially for a default route.

Note: The use of the command-line interface should be replaced by
direct use of libnl so that error conditions can be handled better.  But,
that is being left as an exercise for another day.
Signed-off-by: NGene Czarcinski <gene@czarc.net>
Signed-off-by: NLaine Stump <laine@laine.org>

This should resolve https://bugzilla.redhat.com/show_bug.cgi?id=958907

Recent new addition of code to read/write active network state to the
NETWORK_STATE_DIR in the network driver broke startup for
qemu:///session. The network driver had several state file paths
hardcoded to /var, which could never possibly work in session mode.

This patch modifies *all* state files to use a variable string that is
set differently according to whether or not we're running
privileged. (It turns out that logDir was never used, so it's been
completely eliminated.)

There are very definitely other problems preventing dnsmasq and radvd
from running in non-privileged mode, but it's more consistent to have
the directories used by them be determined in the same fashion.

NB: I've noted before that the network driver is storing its state
(including dnsmasq and radvd state) in /var/lib, while qemu stores its
state in /var/run. It would probably have been better if the two
matched, but it's been this way for a long time, and changing it would
break running installations during an upgrade, so it's best to just
leave it as it is.

The call to virReportError conditionally switched between
two format strings, with different numbers of placeholders.
This meant the format string with no placeholders was not
protected by a "%s".
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

virAsprintf(&foo, "%s", bar) is wasteful compared to
foo = strdup(bar) (or eventually, VIR_STRDUP(foo, bar),
but one thing at a time...).

Noticed while reviewing Laine's attempt to clean up broken
qemu:///session.

* cfg.mk (sc_prohibit_asprintf): Enhance rule.
* src/esx/esx_storage_backend_vmfs.c
(esxStorageBackendVMFSVolumeLookupByKey): Fix offender.
* src/network/bridge_driver.c (networkStateInitialize): Likewise.
* src/nwfilter/nwfilter_dhcpsnoop.c (virNWFilterSnoopDHCPOpen):
Likewise.
* src/storage/storage_backend_sheepdog.c
(virStorageBackendSheepdogRefreshVol): Likewise.
* src/util/vircgroup.c (virCgroupAddTaskStrController): Likewise.
* src/util/virdnsmasq.c (addnhostsAdd): Likewise.
* src/xen/block_stats.c (xenLinuxDomainDeviceID): Likewise.
* src/xen/xen_driver.c (xenUnifiedConnectOpen): Likewise.
* tools/virsh.c (vshGetTypedParamValue): Likewise.
Signed-off-by: NEric Blake <eblake@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.

On the off-chance that creation of persistent configuration file would
fail when defining a network that is already started as transient, the
code would remove the transient data structure and thus the network.

This patch changes the code so that in such case, the network is again
marked as transient and left behind.

This isn't strictly speaking a bugfix, but I realized I'd gotten a bit
too verbose when I chose the names for
VIR_DOMAIN_HOSTDEV_PCI_BACKEND_TYPE_*. This shortens them all a bit.