Commit Graph

421 Commits

Author SHA1 Message Date
Peter Krempa
23c2763b4f network: bridge: Avoid memory leak from networkBuildDhcpDaemonCommandLine
If the leasehelper_path couldn't be found the code would leak the
freshly constructed command structure. Re-arrange code to avoid the
problem.

Found by coverity, broken by baafe668fa.
2014-06-03 14:34:23 +02:00
Julio Faracco
5a2bd4c917 conf: more enum cleanups in "src/conf/domain_conf.h"
In "src/conf/domain_conf.h" there are many enum declarations. The
cleanup in this header filer was started, but it wasn't enough and
there are many other files that has enum variables declared. So, the
commit was starting to be big. This commit finish the cleanup in this
header file and in other files that has enum variables, parameters,
or functions declared.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-06-02 15:32:58 -06:00
Pavel Hrdina
f8a0c9edf0 Fix build on freebsd
On freebsd there isn't known "setlocale" so we have to include locale.h
2014-06-02 16:45:42 +02:00
Nehal J Wani
baafe668fa Add helper program to create custom leases
Introduce helper program to catch events from dnsmasq and maintain a custom
lease file per network. It supports dhcpv4 and dhcpv6. The file is saved as
"<interface-name>.status".

Each lease contains the following info:
<expiry-time (epoch time)> <mac> <iaid> <ip-address> <hostname> <clientid>

Example of custom leases file content:
[
    {
        "iaid": "1221229",
        "ip-address": "2001:db8:ca2:2:1::95",
        "mac-address": "52:54:00:12:a2:6d",
        "hostname": "Fedora20",
        "client-id": "00:04:1a:c1:d9:6b:5a:0a:e2:bc:f8:4b:1e:37:2e:38:22:55",
        "expiry-time": 1393244216
    },
    {
        "ip-address": "192.168.150.208",
        "mac-address": "52:54:00:11:56:b3",
        "hostname": "Wani-PC",
        "client-id": "01:52:54:00:11:56:b3",
        "expiry-time": 1393244248
    }
]

src/Makefile.am:
   * Add options to compile the helper program

src/network/bridge_driver.c:
   * Introduce networkDnsmasqLeaseFileNameCustom()
   * Invoke helper program along with dnsmasq
   * Delete the .status file when corresponding n/w is destroyed.

src/network/leaseshelper.c
   * Helper program to create the custom lease file
2014-06-02 11:45:10 +01:00
Julio Faracco
6000705ab1 conf: use typedefs for enums in "src/conf/{network,interface}_conf.h"
In "src/conf/" there are many enumeration (enum) declarations.
Similar to the recent cleanup to "src/util" directory, it's
better to use a typedef for variable types, function types and
other usages. Other enumeration and folders will be changed to
typedef's in the future. Most of the files changed in this commit
are reltaed to Network (network_conf.* and interface_conf.*) enums.

Signed-off-by: Julio Faracco <jcfaracco@gmail.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-05-05 16:04:53 -06:00
Laine Stump
a431523444 network: use virDirRead in networkMigrateStateFiles
This attempts to follow the same variable name and usage patterns as
the other conversions to virDirRead().
2014-04-28 17:52:46 -06:00
Laine Stump
34cc3b2f10 network: centralize check for active network during interface attach
The check for a network being active during interface attach was being
done individually in several places (by both the lxc driver and the
qemu driver), but those places were too specific, leading to it *not*
being checked when allocating a connection/device from a macvtap or
hostdev network.

This patch puts a single check in networkAllocateActualDevice(), which
is always called before the any network interface is attached to any
type of domain. It also removes all the other now-redundant checks
from the lxc and qemu drivers.

NB: the following patches are prerequisites for this patch, in the
case that it is backported to any branch:

  440beeb network: fix virNetworkObjAssignDef and persistence
  8aaa5b6 network: create statedir during driver initialization
  b9e9549 network: change location of network state xml files
  411c548 network: set macvtap/hostdev networks active if their state
          file exists

This fixes:

  https://bugzilla.redhat.com/show_bug.cgi?id=880483
2014-04-27 12:22:36 +03:00
Laine Stump
411c548668 network: set macvtap/hostdev networks active if their state file exists
libvirt attempts to determine at startup time which networks are
already active, and set their active flags. Previously it has done
this by assuming that all networks are inactive, then setting the
active flag if the network has a bridge device associated with it and
that bridge device exists. This is not useful for macvtap and hostdev
based networks, since they do not use a bridge device.

Of course the reason that such a check had to be done was that the
presence of a status file in the network "stateDir" couldn't be
trusted as an indicator of whether or not a network was active. This
was due to the network driver mistakenly using
/var/lib/libvirt/network to store the status files, rather than
/var/run/libvirt/network (similar to what is done by every other
libvirt driver that stores status xml for its objects). The difference
is that /var/run is cleared out when the host reboots, so you can be
assured that the state file you are seeing isn't just left over from a
previous boot of the host.

Now that the network driver has been switched to using
/var/run/libvirt/network for status, we can also modify it to assume
that any network with an existing status file is by definition active
- we do this when reading the status file. To fine tune the results,
networkFindActiveConfigs() is changed to networkUpdateAllState(),
and only sets active = 0 if the conditions for particular network
types are *not* met.

The result is that during the first run of libvirtd after the host
boots, there are no status files, so no networks are active. Any time
libvirtd is restarted, any network with a status file will be marked
as active (unless the network uses a bridge device and that device for
some reason doesn't exist).
2014-04-27 12:20:39 +03:00
Laine Stump
b9e95491d1 network: change location of network state xml files
For some reason these have been stored in /var/lib, although other
drivers (e.g. qemu and lxc) store their state files in /var/run.

It's much nicer to store state files in /var/run because it is
automatically cleared out when the system reboots. We can then use
existence of the state file as a convenient indicator of whether or
not a particular network is active.

Since changing the location of the state files by itself will cause
problems in the case of a *live* upgrade from an older libvirt that
uses /var/lib (because current status of active networks will be
lost), the network driver initialization has been modified to migrate
any network state files from /var/lib to /var/run.

This will not help those trying to *downgrade*, but in practice this
will only be problematic in two cases

1) If there are networks with network-wide bandwidth limits configured
   *and in use* by a guest during a downgrade to "old" libvirt. In this
   case, the class ID's used for that network's tc rules, as well as
   the currently in-use bandwidth "floor" will be forgotten.

2) If someone does this: 1) upgrade libvirt, 2) downgrade libvirt, 3)
   modify running state of network (e.g. add a static dhcp host, etc),
   4) upgrade. In this case, the modifications to the running network
   will be lost (but not any persistent changes to the network's
   config).
2014-04-27 12:19:57 +03:00
Laine Stump
8aaa5b68ef network: create statedir during driver initialization
This directory should be created when the network driver is first
started up, not just when a dhcp daemon is run. This hasn't posed a
problem in the past, because the directory has always been
pre-existing.
2014-04-27 12:19:13 +03:00
Laine Stump
440beeb7ac network: fix virNetworkObjAssignDef and persistence
Experimentation showed that if virNetworkCreateXML() was called for a
network that was already defined, and then the network was
subsequently shutdown, the network would continue to be persistent
after the shutdown (expected/desired), but the original config would
be lost in favor of the transient config sent in with
virNetworkCreateXML() (which would then be the new persistent config)
(obviously unexpected/not desired).

To fix this, virNetworkObjAssignDef() has been changed to

1) properly save/free network->def and network->newDef for all the
various combinations of live/active/persistent, including some
combinations that were previously considered to be an error but didn't
need to be (e.g. setting a "live" config for a network that isn't yet
active but soon will be - that was previously considered an error,
even though in practice it can be very useful).

2) automatically set the persistent flag whenever a new non-live
config is assigned to the network (and clear it when the non-live
config is set to NULL). the libvirt network driver no longer directly
manipulates network->persistent, but instead relies entirely on
virNetworkObjAssignDef() to do the right thing automatically.

After this patch, the following sequence will behave as expected:

virNetworkDefineXML(X)
virNetworkCreateXML(X') (same name but some config different)
virNetworkDestroy(X)

At the end of these calls, the network config will remain as it was
after the initial virNetworkDefine(), whereas previously it would take
on the changes given during virNetworkCreateXML().

Another effect of this tighter coupling between a) setting a !live def
and b) setting/clearing the "persistent" flag, is that future patches
which change the details of network lifecycle management
(e.g. upcoming patches to fix detection of "active" networks when
libvirtd is restarted) will find it much more difficult to break
persistence functionality.
2014-04-27 11:02:05 +03:00
Daniel P. Berrange
c13a952f69 Replace virNetworkObjPtr with virNetworkDefPtr in network platform APIs
The networkCheckRouteCollision, networkAddFirewallRules and
networkRemoveFirewallRules APIs all take a virNetworkObjPtr
instance, but only ever access the 'def' member. It thus
simplifies testing if the APIs are changed to just take a
virNetworkDefPtr instead

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-04-25 15:44:09 +01:00
Daniel P. Berrange
a66fc27d89 Convert bridge driver over to use new firewall APIs
Update the iptablesXXXX methods so that instead of directly
executing iptables commands, they populate rules in an
instance of virFirewallPtr. The bridge driver can thus
construct the ruleset and then invoke it in one operation
having rollback handled automatically.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-04-25 15:44:09 +01:00
Daniel P. Berrange
3cfa19da22 Replace Pci with PCI throughout
Since it is an abbreviation, PCI should always be fully
capitalized or full lower case, never Pci.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-04-08 11:15:55 +01:00
Laine Stump
6612d1adb7 network: fix problems with SRV records
A patch submitted by Steven Malin last week pointed out a problem with
libvirt's DNS SRV record configuration:

  https://www.redhat.com/archives/libvir-list/2014-March/msg00536.html

When searching for that message later, I found another series that had
been posted by Guannan Ren back in 2012 that somehow slipped between
the cracks:

  https://www.redhat.com/archives/libvir-list/2012-July/msg00236.html

That patch was very much out of date, but also pointed out some real
problems.

This patch fixes all the noted problems by refactoring
virNetworkDNSSrvDefParseXML() and networkDnsmasqConfContents(), then
verifies those fixes by added several new records to the test case.

Problems fixed:

* both service and protocol now have an underscore ("_") prepended on
  the commandline, as required by RFC2782.

  <srv service='sip' protocol='udp' domain='example.com'
       target='tests.example.com' port='5060' priority='10'
       weight='150'/>

  before: srv-host=sip.udp.example.com,tests.example.com,5060,10,150
  after:  srv-host=_sip._udp.example.com,tests.example.com,5060,10,150

* if "domain" wasn't specified in the <srv> element, the extra
  trailing "." will no longer be added to the dnsmasq commandline.

  <srv service='sip' protocol='udp' target='tests.example.com'
       port='5060' priority='10' weight='150'/>

  before: srv-host=sip.udp.,tests.example.com,5060,10,150
  after:  srv-host=_sip._udp,tests.example.com,5060,10,150

* when optional attributes aren't specified, the separating comma is
  also now not placed on the dnsmasq commandline. If optional
  attributes in the middle of the line are not specified, they are
  replaced with a default value in the commandline (1 for port, 0 for
  priority and weight).

  <srv service='sip' protocol='udp' target='tests.example.com'
       port='5060'/>

  before: srv-host=sip.udp.,tests.example.com,5060,,
  after:  srv-host=_sip._udp,tests.example.com,5060

  (actually the would have generated an error, because "optional"
  attributes weren't really optional.)

* The allowed characters for both service and protocol are now limited
  to alphanumerics, plus a few special characters that are found in
  existing names in /etc/services and /etc/protocols. (One exception
  is that both of these files contain names with an embedded ".", but
  "."  can't be used in these fields of an SRV record because it is
  used as a field separator and there is no method to escape a "."
  into a field.) (Previously only the strings "tcp" and "udp" were
  allowed for protocol, but this restriction has been removed, since
  RFC2782 specifically says that it isn't limited to those, and that
  anyway it is case insensitive.)

* the "domain" attribute is no longer required in order to recognize
  the port, priority, and weight attributes during parsing. Only
  "target" is required for this.

* if "target" isn't specified, port, priority, and weight are not
  allowed (since they are meaningless - an empty target means "this
  service is *not available* for this domain").

* port, priority, and weight are now truly optional, as the comments
  originally suggested, but which was not actually true.
2014-03-26 16:42:43 +02:00
Ján Tomko
c97cfce291 Indent top-level labels by one space in src/network/ 2014-03-25 14:58:39 +01:00
Martin Kletzander
5d734987fd Use K&R style for curly braces in src/network/bridge_driver.c
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-03-20 17:16:39 +01:00
Daniel P. Berrange
2835c1e730 Add virLogSource variables to all source files
Any source file which calls the logging APIs now needs
to have a VIR_LOG_INIT("source.name") declaration at
the start of the file. This provides a static variable
of the virLogSource type.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-03-18 14:29:22 +00:00
Pavel Hrdina
b396fae9e2 Fix issue found by coverity and cleanup
Coverity found an issue in lxc_driver and uml_driver that we don't
check the return value of register functions.

I've also updated all other places and unify the way we check the
return value.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2014-03-17 15:02:51 +01:00
Daniel P. Berrange
a84f9bd555 Remove many decls from bridge driver platform header
The bridge_driver_platform.h defines many functions that
a platform driver must implement. Only two of these
functions are actually called from the main bridge driver
code. The remainder can be made internal to the linux
driver only.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-03-11 11:01:51 +00:00
Ján Tomko
9b9d7704b5 Change file names in comments to match the files they are in
Some of these are leftovers from renaming the files, others
are just typos.

Also introduce an ugly awk script to enforce this.
2014-03-10 14:26:04 +01:00
Laine Stump
eed46d4cfe network: unplug bandwidth and call networkRunHook only when appropriate
According to commit b4e0299d if networkAllocateActualDevice() was
successful, it will *always* allocate an iface->data.network.actual,
so we can use this during networkReleaseActualDevice() to know if
there is really anything to undo. We were properly using this
information to only decrement the network connections counter if it
had previously been incremented, but we were unconditionally
unplugging bandwidth and calling the "unplugged" network hook for
*all* interfaces (during qemuProcessStop()) whether they had been
previously plugged or not. This caused problems if a domain failed to
start at some time prior to all interfaces being allocated. (I
encountered this when an interface had a bandwidth floor set but no
inbound QoS).

This patch changes both the call to networkUnplugBandwidth() and the
call to networkRunHook() to only be called if there was a previous
call to "plug" for the same interface.
2014-02-26 13:08:56 +02:00
Laine Stump
0700a3dac4 network: don't even call networkRunHook if there is no network
networkAllocateActualDevice() is called for *all* interfaces, not just
those with type='network'. In that case, it will jump down to its
validate: label immediately, without allocating anything. After
validation is done, two counters are potentially updated (one for the
network, and one for any particular physical device that is chosen),
and then networkRunHook() is called.

This patch refactors that code a slight bit so that networkRunHook()
doesn't get called if netdef is NULL (i.e. type != network) and to
place the conditional increment of dev->connections inside the "if
(netdef)" as well - dev can never be non-null if netdef is null
(because "dev" is the pointer to a device in a network's pool of
devices), so this doesn't have any functional effect, it just makes
the code clearer.
2014-02-26 13:03:49 +02:00
Laine Stump
2122cf3979 network: include plugged interface XML in "plugged" network hook
The network hook script gets called whenever an interface is plugged
into or unplugged from a network, but even though the full XML of both
the network and the domain is included, there is no reasonable way to
determine what exact resources the plugged interface is using:

1) Prior to a recent patch which modified the status XML of interfaces
to include the information about actual hardware resources used, it
would be possible to scan through the domain XML output sent to the
hook, and from there find the correct interface, but that interface
definition would not include any runtime info (e.g. bandwidth or vlan
taken from a portgroup, or which physdev was used in case of a macvtap
network).

2) After the patch modifying the status XML of interfaces, the network
name would no longer be included in the domain XML, so it would be
completely impossible to determine which interface was the one being
plugged.

To solve that problem, this patch includes a single <interface>
element at the beginning of the XML sent to the network hook for
"plugged" and "unplugged" (just inside <hookData>) that is the status
XML of the interface being plugged. This XML will include all info
gathered from the chosen network and portgroup.

NB: due to hardcoded spaces in all of the device *Format() functions,
the <interface> element inside the <hookData> will be indented by 6
spaces rather than 2. I had intended to fix this, but it turns out
that to make virDomainNetDefFormat() indentation relative, I would
have to do the same to virDomainDeviceInfoFormat(), and that function
is called from 19 places - making that a prerequisite of this patch
would cause too many merge difficulties if we needed to backport
network hooks, so I chose to ignore the problem here and fix the
problem for *all* devices in a followup later.
2014-02-25 16:07:36 +02:00
Michal Privoznik
83c404ff9b networkRunHook: Run hook only if possible
Currently, networkRunHook() is called in networkAllocateActualDevice and
friends. These functions, however, doesn't necessarily work on networks,
For example, if domain's interface is defined in this fashion:

    <interface type='bridge'>
      <mac address='52:54:00:0b:3b:16'/>
      <source bridge='virbr1'/>
      <model type='rtl8139'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x09' function='0x0'/>
    </interface>

The networkAllocateActualDevice jumps directly onto 'validate' label as
the interface is not type of 'network'. Hence, @network is left
initialized to NULL and networkRunHook(network, ...) is called. One of
the things that the hook function does is dereference @network. Soupir.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-20 08:56:17 +01:00
Michal Privoznik
4d88294483 bridge_driver.h: Fix build --without-network
The networkNotifyActualDevice function is accepting two arguments, not
one:

qemu/qemu_process.c: In function 'qemuProcessNotifyNets':
qemu/qemu_process.c:2776:47: error: macro "networkNotifyActualDevice" passed 2 arguments, but takes just 1
         if (networkNotifyActualDevice(def, net) < 0)
                                               ^

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-18 19:52:39 +01:00
Michal Privoznik
9de7309125 network: Taint networks that are using hook script
Basically, the idea is copied from domain code, where tainting
exists for a while. Currently, only one taint reason exists -
VIR_NETWORK_TAINT_HOOK to mark those networks which caused invoking
of hook script.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-18 14:46:49 +01:00
Michal Privoznik
f1ab06e43d network: Introduce network hooks
There might be some use cases, where user wants to prepare the host or
its environment prior to starting a network and do some cleanup after
the network has been shut down. Consider all the functionality that
libvirt doesn't currently have as an example what a hook script can
possibly do.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-18 14:46:49 +01:00
Michal Privoznik
e209c07760 networkStartNetwork: Be more verbose
The lack of debug printings might be frustrating in the future.
Moreover, this function doesn't follow the usual pattern we have in the
rest of the code:

  int ret = -1;
  /* do some work */
  ret = 0;
cleanup:
  /* some cleanup work */
  return ret;

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-10 11:47:24 +01:00
Eric Blake
11f20e43f1 event: move event filtering to daemon (regression fix)
https://bugzilla.redhat.com/show_bug.cgi?id=1058839

Commit f9f56340 for CVE-2014-0028 almost had the right idea - we
need to check the ACL rules to filter which events to send.  But
it overlooked one thing: the event dispatch queue is running in
the main loop thread, and therefore does not normally have a
current virIdentityPtr.  But filter checks can be based on current
identity, so when libvirtd.conf contains access_drivers=["polkit"],
we ended up rejecting access for EVERY event due to failure to
look up the current identity, even if it should have been allowed.

Furthermore, even for events that are triggered by API calls, it
is important to remember that the point of events is that they can
be copied across multiple connections, which may have separate
identities and permissions.  So even if events were dispatched
from a context where we have an identity, we must change to the
correct identity of the connection that will be receiving the
event, rather than basing a decision on the context that triggered
the event, when deciding whether to filter an event to a
particular connection.

If there were an easy way to get from virConnectPtr to the
appropriate virIdentityPtr, then object_event.c could adjust the
identity prior to checking whether to dispatch an event.  But
setting up that back-reference is a bit invasive.  Instead, it
is easier to delay the filtering check until lower down the
stack, at the point where we have direct access to the RPC
client object that owns an identity.  As such, this patch ends
up reverting a large portion of the framework of commit f9f56340.
We also have to teach 'make check' to special-case the fact that
the event registration filtering is done at the point of dispatch,
rather than the point of registration.  Note that even though we
don't actually use virConnectDomainEventRegisterCheckACL (because
the RegisterAny variant is sufficient), we still generate the
function for the purposes of documenting that the filtering
takes place.

Also note that I did not entirely delete the notion of a filter
from object_event.c; I still plan on using that for my upcoming
patch series for qemu monitor events in libvirt-qemu.so.  In
other words, while this patch changes ACL filtering to live in
remote.c and therefore we have no current client of the filtering
in object_event.c, the notion of filtering in object_event.c is
still useful down the road.

* src/check-aclrules.pl: Exempt event registration from having to
pass checkACL filter down call stack.
* daemon/remote.c (remoteRelayDomainEventCheckACL)
(remoteRelayNetworkEventCheckACL): New functions.
(remoteRelay*Event*): Use new functions.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Drop unused parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/domain_event.c (virDomainEventFilter): Delete unused
function.
* src/conf/network_event.c (virNetworkEventFilter): Likewise.
* src/libxl/libxl_driver.c: Adjust caller.
* src/lxc/lxc_driver.c: Likewise.
* src/network/bridge_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/test/test_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xen/xen_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-02-05 08:03:31 -07:00
Laine Stump
eafb53fec2 network: disallow <bandwidth>/<mac> for bridged/macvtap/hostdev networks
https://bugzilla.redhat.com/show_bug.cgi?id=1057321

pointed out that we weren't honoring the <bandwidth> element in
libvirt networks using <forward mode='bridge'/>. In fact, these
networks are just a method of giving a libvirt network name to an
existing Linux host bridge on the system, and libvirt doesn't have
enough information to know where to set such limits. We are working on
a method of supporting network bandwidths for some specific cases of
<forward mode='bridge'/>, but currently libvirt doesn't support it. So
the proper thing to do now is just log an error when someone tries to
put a <bandwidth> element in that type of network. (It's unclear if we
will be able to do proper bandwidth limiting for macvtap networks, and
most definitely we will not be able to support it for hostdev
networks).

While looking through the network XML documentation and comparing it
to the networkValidate function, I noticed that we also ignore the
presence of a mac address in the config in the same cases, rather than
failing so that the user will understand that their desired action has
not been taken.

This patch updates networkValidate() (which is called any time a
persistent network is defined, or a transient network created) to log
an error and fail if it finds either a <bandwidth> or <mac> element
and the network forward mode is anything except 'route'. 'nat', or
nothing. (Yes, neither of those elements is acceptable for any macvtap
mode, nor for a hostdev network).

NB: This does *not* cause failure to start any existing network that
contains one of those elements, so someone might have erroneously
defined such a network in the past, and that network will continue to
function unmodified. I considered it too disruptive to suddenly break
working configs on the next reboot after a libvirt upgrade.
2014-02-05 15:04:58 +02:00
Laine Stump
66f75925eb network: change default of forwardPlainNames to 'yes'
The previous patch fixed "forwardPlainNames" so that it really is
doing only what is intended, but left the default to be
"forwardPlainNames='no'". Discussion around the initial version of
that patch led to the decision that the default should instead be
"forwardPlainNames='yes'" (i.e. the original behavior before commit
f3886825). This patch makes that change to the default.
2014-02-04 12:00:26 +02:00
Laine Stump
f69a6b987d network: only prevent forwarding of DNS requests for unqualified names
In commit f386825 we began adding the options

  --domain-needed
  --local=/$mydomain/

to all dnsmasq commandlines with the stated reason of preventing
forwarding of DNS queries for names that weren't fully qualified
domain names ("FQDN", i.e. a name that included some "."s and a domain
name). This was later changed to

  domain-needed
  local=/$mydomain/

when we moved the options from the dnsmasq commandline to a conf file.

The original patch on the list, and discussion about it, is here:

  https://www.redhat.com/archives/libvir-list/2012-August/msg01594.html

When a domain name isn't specified (mydomain == ""), the addition of
"domain-needed local=//" will prevent forwarding of domain-less
requests to the virtualization host's DNS resolver, but if a domain
*is* specified, the addition of "local=/domain/" will prevent
forwarding of any requests for *qualified* names within that domain
that aren't resolvable by libvirt's dnsmasq itself.

An example of the problems this causes - let's say a network is
defined with:

   <domain name='example.com'/>
   <dhcp>
      ..
      <host mac='52:54:00:11:22:33' ip='1.2.3.4' name='myguest'/>
   </dhcp>

This results in "local=/example.com/" being added to the dnsmasq options.

If a guest requests "myguest" or "myguest.example.com", that will be
resolved by dnsmasq. If the guest asks for "www.example.com", dnsmasq
will not know the answer, but instead of forwarding it to the host, it
will return NOT FOUND to the guest. In most cases that isn't the
behavior an admin is looking for.

A later patch (commit 4f595ba) attempted to remedy this by adding a
"forwardPlainNames" attribute to the <dns> element. The idea was that
if forwardPlainNames='yes' (default is 'no'), we would allow
unresolved names to be forwarded. However, that patch was botched, in
that it only removed the "domain-needed" option when
forwardPlainNames='yes', and left the "local=/mydomain/".

Really we should have been just including the option "--domain-needed
--local=//" (note the lack of domain name) regardless of the
configured domain of the network, so that requests for names without a
domain would be treated as "local to dnsmasq" and not forwarded, but
all others (including those in the network's configured domain) would
be forwarded. We also shouldn't include *either* of those options if
forwardPlainNames='yes'. This patch makes those corrections.

This patch doesn't remedy the fact that default behavior was changed
by the addition of this feature. That will be handled in a subsequent
patch.
2014-02-04 12:00:26 +02:00
Michal Privoznik
122cd16982 Revert "networkAllocateActualDevice: Set QoS for bridgeless networks too"
This reverts commit 2996e6be19
and some parts of 2636dc8c4d.

The former one tried to implement QoS setting on bridgeless networks.
However, as discussed upstream [1], the patch is far away from being
useful in even a single case. The whole idea of network QoS is to have
aggregated limits over several interfaces. This patch is doing
completely the opposite when merging two QoS settings (from the network
and the domain interface) into one which is then set at the domain
interface itself, not the network.

The latter one is the test for the previous one. Now none of them makes
sense.

1: https://www.redhat.com/archives/libvir-list/2014-January/msg01441.html

Conflicts:
	tests/virnetdevbandwidthtest.c: New test has been introduced since
    then.
2014-01-29 19:01:19 +01:00
Michal Privoznik
2996e6be19 networkAllocateActualDevice: Set QoS for bridgeless networks too
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: Michal Privoznik <mprivozn@redhat.com>
2014-01-27 12:11:27 +01:00
Eric Blake
f9f5634053 event: filter global events by domain:getattr ACL [CVE-2014-0028]
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>
2014-01-15 13:55:21 -07:00
Eric Blake
36dd0bd88a event: make network events easier to use without casts
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: Eric Blake <eblake@redhat.com>
2014-01-07 13:05:27 -07:00
Lénaïc Huard
538daf7f3a Fix bridge configuration when OUTPUT policy is DROP on the host
When the host is configured with very restrictive firewall (default policy
is DROP for all chains, including OUTPUT), the bridge driver for Linux
adds netfilter entries to allow DHCP and DNS requests to go from the VM
to the dnsmasq of the host.

The issue that this commit fixes is the fact that a DROP policy on the OUTPUT
chain blocks the DHCP replies from the host’s dnsmasq to the VM.
As DHCP replies are sent in UDP, they are not caught by any --ctstate ESTABLISHED
rule and so, need to be explicitly allowed.

Signed-off-by: Lénaïc Huard <lenaic@lhuard.fr.eu.org>
2014-01-07 18:18:29 +01:00
Eric Blake
31b5bad9ff event: make deregister return value match docs
Ever since their introduction (commit 1509b80 in v0.5.0 for
virConnectDomainEventRegister, commit 4445723 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: Eric Blake <eblake@redhat.com>
2014-01-07 06:53:40 -07:00
Daniel P. Berrange
6e2545c07b Add 'detail' arg to network lifecycle event internals
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: Daniel P. Berrange <berrange@redhat.com>
2013-12-13 16:07:54 +00:00
Cédric Bosdonnat
cd88e9293a Added network events to the bridged network driver 2013-12-11 13:32:21 +00:00
John Ferlan
b17168cbf6 bridge_driver: Resolve Coverity CHECKED_RETURN warning
The networkRegister() didn't check the return status of the
virRegisterNetworkDriver() call like other callers, so just
check and handle here as well.
2013-12-04 06:27:20 -05:00
Laine Stump
54f9492353 network: properly update iptables rules during net-update
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.
2013-11-28 16:55:20 +02:00
Eric Blake
e44a9a70d3 maint: fix comma style issues: remaining code
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: Eric Blake <eblake@redhat.com>
2013-11-20 09:14:55 -07:00
Michal Privoznik
223ce2f1a3 networkBuildDhcpDaemonCommandLine: Don't leak @configstr and @configfile
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2013-11-14 17:44:20 +01:00
Laine Stump
89e2a6c88c util: use size_t instead of unsigned int for num_virtual_functions
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.
2013-11-08 14:31:11 +02:00
Laine Stump
b4e0299d4f network: fix connections count in case of allocate failure
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--").
2013-11-06 13:14:57 +02:00
Hongwei Bi
3a8cc9cf50 networkStartDhcpDaemon: Check for dnsmasqCapsRefresh failure
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: Hongwei Bi <hwbi2008@gmail.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2013-10-22 17:14:13 +01:00
Laszlo Ersek
51e184e982 bridge driver: don't masquerade local subnet broadcast/multicast packets
Packets sent by guests on virbrN, *or* by dnsmasq on the same, to
- 255.255.255.255/32 (netmask-independent local network broadcast
  address), or to
- 224.0.0.0/24 (local subnetwork multicast range)
are never forwarded, hence it is not necessary to masquerade them.

In fact we must not masquerade them: translating their source addresses or
source ports (where applicable) may confuse receivers on virbrN.

One example is the DHCP client in OVMF (= UEFI firmware for virtual
machines):

  http://thread.gmane.org/gmane.comp.bios.tianocore.devel/1506/focus=2640

It expects DHCP replies to arrive from remote source port 67. Even though
dnsmasq conforms to that, the destination address (255.255.255.255) and
the source address (eg. 192.168.122.1) in the reply allow the UDP
masquerading rule to match, which rewrites the source port to or above
1024. This prevents the DHCP client in OVMF from accepting the packet.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=709418

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
2013-09-25 08:31:50 -04:00
Diego Woitasen
22547b4c98 Add forwarder attribute to <dns/> element
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: Diego Woitasen <diego.woitasen@vhgroup.net>
Signed-off-by: Eric Blake <eblake@redhat.com>
2013-09-17 17:47:33 -06:00
Michal Privoznik
0f396366fe bridge_driver: Introduce networkObjFromNetwork
Similarly to qemu_driver.c, we can join often repeating code of looking
up network into one function: networkObjFromNetwork.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2013-08-29 11:03:33 +02:00
Ján Tomko
d8bd24a9ec Remove the space before the slash in network XML
This matches the style we use elsewhere and allows
nat-network-dns-srv-record{,-minimal}.xml to be tested in
network XML -> XML test.
2013-08-28 08:05:46 +02:00
Roman Bogorodskiy
f083ff82ed bridge driver: implement networkEnableIpForwarding for BSD
Implement networkEnableIpForwarding() using BSD style sysctl.
2013-08-21 16:28:19 -06:00
Laine Stump
4f595ba61c network: permit upstream forwarding of unqualified DNS names
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 f3868259ca 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.
2013-08-14 09:46:22 -04:00
Guido Günther
0adc2b977d Add missing ATTRIBUTE_UNUSED
to fix the kFreeBSD build.

The network parameter is unused in networkCheckRouteCollision:

    http://honk.sigxcpu.org:8001/job/libvirt-build-debian-jessie-kfreebsd64/
2013-08-12 21:30:29 +02:00
Roman Bogorodskiy
4ac708f250 bridge driver: extract platform specifics
* 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: Eric Blake <eblake@redhat.com>
2013-08-01 15:47:02 -06:00
John Ferlan
cefb97fb81 virStateDriver - Separate AutoStart from Initialize
Adjust these drivers to handle their Autostart functionality after each
of the drivers has gone through their Initialization functions
2013-07-26 09:30:53 -04:00
Roman Bogorodskiy
73cf5b9634 bridge driver: use more general function names
Continue preparation for extracting platform-specific
parts from bridge_driver: s/Iptables/Firewall/ for
firewall related function names.
2013-07-23 13:22:25 +02:00
Roman Bogorodskiy
162e47795d bridge driver: s/network_driver/virNetworkDriverState/
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.
2013-07-22 14:16:12 +02:00
Daniel P. Berrange
7ecb44774b Convert 'int i' to 'size_t i' in src/network/ files
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>
2013-07-10 17:55:16 +01:00
Michal Privoznik
9729d847b5 Adapt to VIR_ALLOC and virAsprintf in src/network/* 2013-07-10 11:07:32 +02:00
Daniel P. Berrange
bbaa4e1cba Add access control filtering of network objects
Ensure that all APIs which list network objects filter
them against the access control system.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-07-03 15:54:53 +01:00
Roman Bogorodskiy
477a619e1b Drop iptablesContext
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.
2013-07-01 13:47:37 -04:00
Ján Tomko
658c932ab4 bridge: don't crash on bandwidth unplug with no bandwidth
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
2013-06-27 12:11:42 +02:00
Laine Stump
4b42e3b97f network: allow <vlan> in type='hostdev' networks
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.
2013-06-26 03:25:19 -04:00
Daniel P. Berrange
453da48b12 Add ACL checks into the network driver
Insert calls to the ACL checking APIs in all network driver
entrypoints.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-06-24 15:25:44 +01:00
Laine Stump
2bdf548f5f network: increase max number of routes
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.
2013-06-20 14:23:36 -04:00
Eric Blake
1add9c78da maint: don't use config.h in .h files
Enforce the rule that .h files don't need to (redundantly)
include <config.h>.

* cfg.mk (sc_prohibit_config_h_in_headers): New rule.
(_virsh_includes): Delete; instead, inline a smaller number of
exclusions...
(exclude_file_name_regexp--sc_require_config_h)
(exclude_file_name_regexp--sc_require_config_h_first): ...here.
* daemon/libvirtd.h (includes): Fix offenders.
* src/driver.h (includes): Likewise.
* src/gnutls_1_0_compat.h (includes): Likewise.
* src/libxl/libxl_conf.h (includes): Likewise.
* src/libxl/libxl_driver.h (includes): Likewise.
* src/lxc/lxc_conf.h (includes): Likewise.
* src/lxc/lxc_driver.h (includes): Likewise.
* src/lxc/lxc_fuse.h (includes): Likewise.
* src/network/bridge_driver.h (includes): Likewise.
* src/phyp/phyp_driver.h (includes): Likewise.
* src/qemu/qemu_conf.h (includes): Likewise.
* src/util/virnetlink.h (includes): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-06-05 05:53:25 -06:00
Michal Privoznik
1f24f68225 qemu: Adapt qemuBuildInterfaceCommandLine to to multiqueue net
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.
2013-05-22 17:24:27 +02:00
Osier Yang
5f48ddafbe src/network: Remove the whitespace before ';' 2013-05-21 23:41:43 +08:00
Gene Czarcinski
ccff335f83 Support for static routes on a virtual bridge
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: Gene Czarcinski <gene@czarc.net>
Signed-off-by: Laine Stump <laine@laine.org>
2013-05-13 16:14:40 -04:00
Michal Privoznik
6b936bd79c Adapt to VIR_STRDUP and VIR_STRNDUP in src/network/* 2013-05-09 14:00:45 +02:00
Laine Stump
2ffd87d820 network: fix network driver startup for qemu:///session
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.
2013-05-03 10:17:29 -04:00
Daniel P. Berrange
5c1678ab2c Fix format string handling in network driver
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: Daniel P. Berrange <berrange@redhat.com>
2013-05-03 10:29:07 +01:00
Eric Blake
25ae3d3015 build: avoid useless virAsprintf
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: Eric Blake <eblake@redhat.com>
2013-05-02 13:35:26 -06:00
Michal Privoznik
7c9a2d88cd virutil: Move string related functions to virstring.c
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.
2013-05-02 16:56:55 +02:00
John Ferlan
c0b86c8c05 Need to call virFreeError after virSaveLastError 2013-04-30 13:39:28 -04:00
Peter Krempa
8e91890015 network: Don't remove transient network if creating of config file fails
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.
2013-04-30 09:08:40 +02:00
Laine Stump
19635f7d0d conf: remove extraneous _TYPE from driver backend enums
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.
2013-04-26 21:51:12 -04:00
Laine Stump
d64e114f14 network: support <driver name='vfio'/> in network definitions
I remembered to document this bit, but somehow forgot to implement it.

This adds <driver name='kvm|vfio'/> as a subelement to the <forward>
element of a network (this puts it parallel to the match between
mode='hostdev' attribute in a network and type='hostdev' in an
<interface>).

Since it's already documented, only the parser, formatter, backend
driver recognition (it just translates/moves the flag into the
<interface> at the appropriate time), and a test case were needed.

(I used a separate enum for the values both because the original is
defined in domain_conf.h, which is unavailable from network_conf.h,
and because in the future it's possible that we may want to support
other non-hostdev oriented driver names in the network parser; this
makes sure that one can be expanded without the other).
2013-04-26 21:51:12 -04:00
Laine Stump
9f80fc1bd5 conf: put hostdev pci address in a struct
There will soon be other items related to pci hostdevs that need to be
in the same part of the hostdevsubsys union as the pci address (which
is currently a single member called "pci". This patch replaces the
single member named pci with a struct named pci that contains a single
member named "addr".
2013-04-25 21:23:38 -04:00
Daniel P. Berrange
90430791ae Make driver method names consistent with public APIs
Ensure that all drivers implementing public APIs use a
naming convention for their implementation that matches
the public API name.

eg for the public API   virDomainCreate make sure QEMU
uses qemuDomainCreate and not qemuDomainStart

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-24 11:00:18 +01:00
Daniel P. Berrange
d407a11eab Dedicated name for sub-driver open/close methods
It will simplify later work if the sub-drivers have dedicated
APIs / field names. ie virNetworkDriver should have
virDrvNetworkOpen and virDrvNetworkClose methods

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-24 10:59:54 +01:00
Daniel P. Berrange
abe038cfc0 Extend previous check to validate driver struct field names
Ensure that the driver struct field names match the public
API names. For an API virXXXX we must have a driver struct
field xXXXX. ie strip the leading 'vir' and lowercase any
leading uppercase letters.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-04-24 10:59:53 +01:00
Peter Krempa
446dd66b7c network: bridge_driver: don't lose transient networks on daemon restart
Until now tranisent networks weren't really useful as libvirtd wasn't
able to remember them across restarts. This patch adds support for
loading status files of transient networks (that already were generated)
so that the status isn't lost.

This patch chops up virNetworkObjUpdateParseFile and turns it into
virNetworkLoadState and a few friends that will help us to load status
XMLs and refactors the functions that are loading the configs to use
them.
2013-04-19 16:43:47 +02:00
Peter Krempa
45012bc85b network: remove autostart flag from network when undefining it
When turning a started persistent network into a transient one we forgot
to remove the autostart flag that is no longer valid at that point.
2013-04-18 09:44:14 +02:00
Osier Yang
bc95be5dea cleanup: Remove the duplicate header
Detected by a simple Shell script:

for i in $(git ls-files -- '*.[ch]'); do
    awk 'BEGIN {
        fail=0
    }
    /# *include.*\.h/{
        match($0, /["<][^">]*[">]/)
        arr[substr($0, RSTART+1, RLENGTH-2)]++
    }
    END {
        for (key in arr) {
            if (arr[key] > 1) {
                fail=1
                printf("%d %s\n", arr[key], key)
            }
        }
        if (fail == 1)
            exit 1
    }' $i

    if test $? != 0; then
        echo "Duplicate header(s) in $i"
    fi
done;

A later patch will add the syntax-check to avoid duplicate
headers.
2013-04-17 15:49:35 +08:00
Michal Privoznik
f3fb916de9 bandwidth: Require network QoS if interface uses 'floor'
By current implementation, network inbound is required in order
to use 'floor' for guaranteeing  minimal throughput. This is so,
because we want user to tell us the maximal throughput of the
network instead of finding out ourselves (and detect bogus values
in case of virtual interfaces). However, we are nowadays
requiring this only on documentation level. So if user starts a
domain with 'floor' set on one its interfaces, we silently ignore
the setting. We should error out instead.
2013-03-11 10:51:32 +01:00
Laine Stump
db2536a627 Revert "Add support for <option> tag in network config"
This reverts commit 383ebc4694.

We decided the xml for this feature needed more thought to make sure
we are doing it the best way, in particular wrt option values that
have multiple items.
2013-02-27 10:55:24 -05:00
Gene Czarcinski
0b73a763f3 use client id for IPv6 DHCP host definition
Originally, only a host name was used to associate a
DHCPv6 request with a specific IPv6 address.  Further testing
demonstrates that this is an unreliable method and, instead,
a client-id or DUID needs to be used.  According to DHCPv6
standards, this id can be a duid-LLT, duid-LL, or duid-UUID
even though dnsmasq will accept almost any text string.

Although validity checking of a specified string makes sure it is
hexadecimal notation with bytes separated by colons, there is no
rigorous check to make sure it meets the standard.

Documentation and schemas have been updated.

Signed-off-by: Gene Czarcinski <gene@czarc.net>
Signed-off-by: Laine Stump <laine@laine.org>
2013-02-25 02:49:06 -05:00
Pieter Hollants
383ebc4694 Add support for <option> tag in network config
This patch adds support for a new <option>-Tag in the <dhcp> block of
network configs, based on a subset of the fifth proposal by Laine
Stump in the mailing list discussion at
https://www.redhat.com/archives/libvir-list/2012-November/msg01054.html.
Any such defined option will result in a dhcp-option=<number>,"<value>"
statement in the generated dnsmasq configuration file.

Currently, DHCP options can be specified by number only and there is
no whitelisting or blacklisting of option numbers, which should
probably be added.

Signed-off-by: Pieter Hollants <pieter@hollants.com>
Signed-off-by: Laine Stump <laine@laine.org>
2013-02-22 19:45:19 -05:00
Natanael Copa
bac8b2ca09 net: use structs for address and port ranges
We pass over the address/port start/end values many times so we put
them in structs.

Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Laine Stump <laine@laine.org>
2013-02-19 14:42:18 -05:00
Natanael Copa
1716e7a6c5 net: add support for specifying port range for forward mode nat
Let users set the port range to be used for forward mode NAT:

...
  <forward mode='nat'>
    <nat>
      <port start='1024' end='65535'/>
    </nat>
  </forward>
...

Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Laine Stump <laine@laine.org>
2013-02-19 14:42:18 -05:00
Natanael Copa
905629f47e net: support set public ip range for forward mode nat
Support setting which public ip to use for NAT via attribute
address in subelement <nat> in <forward>:

...
  <forward mode='nat'>
      <address start='1.2.3.4' end='1.2.3.10'/>
  </forward>
...

This will construct an iptables line using:

  '-j SNAT --to-source <start>-<end>'

instead of:

  '-j MASQUERADE'

Signed-off-by: Natanael Copa <ncopa@alpinelinux.org>
Signed-off-by: Laine Stump <laine@laine.org>
2013-02-19 14:42:18 -05:00
John Ferlan
3fa23653ee network: Remove conditional settings to resolve resource leak
The conditional setting of cmdout in networkBuildDhcpDaemonCommandLine()
caused Coverity to complain that 'cmd' could be leaked if !cmdout.  Since
the function is local and only called with cmdout being passed those checks
have been removed.
2013-02-05 16:51:07 -05:00
Daniel P. Berrange
202535601c Rename all PCI device functions to have a standard name prefix
Rename all the pciDeviceXXX and pciXXXDevice APIs to have a
fixed virPCIDevice name prefix
2013-02-05 19:22:25 +00:00
John Ferlan
011d40059d network: Add coverity[leaked_handle] to ignore error
On error, the 'tapfd' in networkStartNetworkVirtual() is synonymous
with 'macTapIfName' and will be closed in the appropriate error path.
2013-01-22 16:59:46 +01:00
John Ferlan
7d31dd6494 network: Remove dead code getting, but not using ipdef
The fetch of 'ipdef' in networkRefreshDhcpDaemon() when the loop to fill
in ipv4def fails to find an ipv4 address with dhcp defined. The filled in
ipdef value was not used.  Code was made unnecessary with commit it 2d5cd1.
2013-01-17 23:46:36 +01:00
Laine Stump
7d480a4650 network: use bandwidth from portgroup when appropriate
The bandwidth plug and unplug functions were assuming that an
interface's bandwidth setting was always specified directly in the
domain's <interface> definition, but that's not necessarily true - it
could have been obtained from a <portgroup> definition in the network
definition. This patch fixes those functions to use
virDomainNetGetActualBandwidth(), which gets the bandwidth pointer
from iface->data.network.actual if it exists, otherwise returns
iface->bandwidth.
2013-01-17 12:38:51 -05:00
John Ferlan
35ed25bde9 network: Resolve some issues around vlan copying
Remove extraneous check for 'netdef' when dereferencing for vlan.nTags.
Prior code would already check if netdef was NULL.

Coverity complained about a path where the 'vlan' was potentially valid,
but a prior checks may not have allocated 'iface->data.network.actual',
so like other paths it needs to be allocated on the fly.

Move the copying of vlan up earlier in networkAllocateActualDevice, so
that actual.type gets properly set.

Since the first assignment to vlan is redundant except in the case of
jumping immediately to validate from the start of the function,
eliminate its initial setting at the top of the function in favor of
calling the helper function virDomainNetGetActualVlan() (which doesn't
depend on the local vlan pointer being initialized) down at validate:

Signed-off-by: Laine Stump <laine@redhat.com>
2013-01-17 12:38:51 -05:00
Peter Krempa
e6d74d8db5 network: Report real error if addition of firewall rules fails
If addition of rules in networkAddIptablesRules() failed the real error
was masked by error reported when trying to clean up the remaining
rules.

With this patch the original error message is saved and set back after
the removal is complete.
2013-01-11 14:05:52 +01:00
Peter Krempa
bb19491cf5 network: bridge: Fix regression when defining persistent networks
Commit 0211fd6e04 introduced regression
where newly defined networks were not made persistent.

This patch makes the network persistent on each successful definition.
2013-01-11 14:05:51 +01:00
Daniel P. Berrange
f24404a324 Rename virterror.c virterror_internal.h to virerror.{c,h} 2012-12-21 11:19:50 +00:00
Daniel P. Berrange
e861b31275 Rename uuid.{c,h} to viruuid.{c,h} 2012-12-21 11:19:49 +00:00
Daniel P. Berrange
44f6ae27fe Rename util.{c,h} to virutil.{c,h} 2012-12-21 11:19:49 +00:00
Daniel P. Berrange
3ddddd98c3 Rename pci.{c,h} to virpci.{c,h} 2012-12-21 11:17:14 +00:00
Daniel P. Berrange
ab9b7ec2f6 Rename memory.{c,h} to viralloc.{c,h} 2012-12-21 11:17:14 +00:00
Daniel P. Berrange
936d95d347 Rename logging.{c,h} to virlog.{c,h} 2012-12-21 11:17:14 +00:00
Daniel P. Berrange
47cdbac47d Rename iptables.{c,h} to viriptables.{c,h} 2012-12-21 11:17:13 +00:00
Daniel P. Berrange
4af71715be Rename dnsmasq.{c,h} to virdnsmasq.{c,h} 2012-12-21 11:17:13 +00:00
Daniel P. Berrange
04d9510f50 Rename command.{c,h} to vircommand.{c,h} 2012-12-21 11:17:13 +00:00
Daniel P. Berrange
2005f7b552 Rename buf.{c,h} to virbuffer.{c,h}
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-12-21 11:17:12 +00:00
Laine Stump
4b31da3478 network: don't require private addresses if dnsmasq uses SO_BINDTODEVICE
This is yet another refinement to the fix for CVE-2012-3411:

   https://bugzilla.redhat.com/show_bug.cgi?id=833033

It turns out that it would be very intrusive to correctly backport the
entire --bind-dynamic option to older dnsmasq versions
(e.g. dnsmasq-2.48 that is used on RHEL6.x and CentOS 6.x), but very
simple to patch those versions to just use SO_BINDTODEVICE on all
their listening sockets (SO_BINDTODEVICE also has the desired effect
of permitting only traffic that was received on the interface(s) where
dnsmasq was set to listen.)

This patch modifies the dnsmasq capabilities detection to detect the
string:

    --bind-interfaces with SO_BINDTODEVICE

in the output of "dnsmasq --version", and in that case realize that
using the old --bind-interfaces option is just as safe as
--bind-dynamic (and therefore *not* forbid creation of networks that
use public IP address ranges).

If -bind-dynamic is available, it is still preferred over
--bind-interfaces.

Note that this patch does no harm in upstream, or in any distro's
downstream if it happens to end up there, but builds for distros that
have a new enough dnsmasq to support --bind-dynamic do *NOT* need to
specifically backport this patch; it's only required for distro
releases that have dnsmasq too old to have --bind-dynamic (and those
distros will need to add the SO_BINDTODEVICE patch to dnsmasq,
*including the extra string in the --version output*, as well.
2012-12-17 15:51:19 -05:00
Laine Stump
bc5b270c44 network: fix indentation of networkDnsmasqConfContents
Somehow I managed to push the changes to this file with improper
indentation. This patch just re-indents, reformats the comment lines,
and re-groups a couple of multi-line strings so that they fit within
80 columns. The resulting binary should be identical.
2012-12-17 15:08:54 -05:00
Laine Stump
e3802e13df network: fix (non)update of dnsmasq config during virDomainUpdateDeviceFlags
A forgotten "!" in recently-modified code at the top of
networkRefreshDaemon() meant an improper early return, which led to 1)
dnsmasq config files not being updated from the newly modified config,
and 2) dnsmasq not being sent a SIGHUP so that it could learn about
the changes to the config.

virNetworkDefGetIpByIndex() returns NULL if there are no ip objects of
the requested type, and if there are no IP elements, then dnsmasq
shouldn't be running, so we can return early. Otherwise we should
rewrite the config files and send a SIGHUP.
2012-12-14 13:37:17 -05:00
Laine Stump
d66eb78667 network: prevent dnsmasq from listening on localhost
This patch resolves the problem reported in:

   https://bugzilla.redhat.com/show_bug.cgi?id=886663

The source of the problem was the fix for CVE 2011-3411:

   https://bugzilla.redhat.com/show_bug.cgi?id=833033

which was originally committed upstream in commit
753ff83a50. That commit improperly
removed the "--except-interface lo" from dnsmasq commandlines when
--bind-dynamic was used (based on comments in the latter bug).

It turns out that the problem reported in the CVE could be eliminated
without removing "--except-interface lo", and removing it actually
caused each instance of dnsmasq to listen on localhost on port 53,
which created a new problem:

If another instance of dnsmasq using "bind-interfaces" (instead of
"bind-dynamic") had already been started (or if another instance
started later used "bind-dynamic"), this wouldn't have any immediately
visible ill effects, but if you tried to start another dnsmasq
instance using "bind-interfaces" *after* starting any libvirt
networks, the new dnsmasq would fail to start, because there was
already another process listening on port 53.

(Subsequent to the CVE fix, another patch changed the network driver
to put dnsmasq options in a conf file rather than directly on the
dnsmasq commandline, but preserved the same options.)

This patch changes the network driver to *always* add
"except-interface=lo" to dnsmasq conf files, regardless of whether we use
bind-dynamic or bind-interfaces. This way no libvirt dnsmasq instances
are listening on localhost (and the CVE is still fixed).

The actual code change is miniscule, but must be propogated through all
of the test files as well.
2012-12-13 12:15:03 -05:00
Eric Blake
7339bc4ced network: match xml warning message
I noticed that /var/lib/libvirt/dnsmasq/*.conf used the wrong word;
it was intended to match the wording in src/util/xml.c.

* src/network/bridge_driver.c (networkDnsmasqConfContents): Fix typo.
* tests/networkxml2confdata/*.conf: Update accordingly.
2012-12-12 15:12:58 -07:00
Michal Privoznik
ae757743dc network: Create real network status files
Currently, we are only keeping a inactive XML configuration
in status dir. This is no longer enough as we need to keep
this class_id attribute so we don't overwrite old entries
when the daemon restarts. However, since there has already
been release which has just <network/> as root element,
and we want to keep things compatible, detect that loaded
status file is older one, and don't scream about it.
2012-12-11 18:42:54 +01:00
Michal Privoznik
07d1b6b5b1 bandwidth: Create network bandwidth (un)plug functions
Network should be notified if we plug in or unplug an
interface, so it can perform some action, e.g. set/unset
network part of QoS. However, we are doing this in very
early stage, so iface->ifname isn't filled in yet. So
whenever we want to report an error, we must use a different
identifier, e.g. the MAC address.
2012-12-11 18:41:47 +01:00
Michal Privoznik
67159f1c60 bandwidth: Create hierarchical shaping classes
These classes can borrow unused bandwidth. Basically,
only egress qdsics can have classes, therefore we can
do this kind of traffic shaping only on host's outgoing,
that is domain's incoming traffic.
2012-12-11 18:36:55 +01:00
Gene Czarcinski
8b32c80df0 network: put dnsmasq parameters in conf-file instead of command line
This patch changes how parameters are passed to dnsmasq.  Instead of
being on the command line, the parameters are put into a file (one
parameter per line) and a commandline --conf-file= specifies the
location of the file.  The file is located in the same directory as
the leases file.

Putting the dnsmasq parameters into a configuration file
allows them to be examined and more easily understood than
examining the command lines displayed by "ps ax".  This is
especially true when a number of networks have been started.

When the use of dnsmasq was originally done, the required command line
was simple, but it has gotten more complicated over time and will
likely become even more complicated in the future.

Note: The test conf files have all been renamed .conf instead of
.argv, and tests/networkxml2xmlargvdata was moved to
tests/networkxml2xmlconfdata.
2012-12-11 05:49:45 -05:00
Gene Czarcinski
2d5cd1d724 network: add support for DHCPv6
The DHCPv6 support includes IPV6 dhcp-range and dhcp-host for one
IPv6 subnetwork on one interface.  This support will only work
if dnsmasq version >= 2.64; otherwise an error occurs if
dhcp-range or dhcp-host is specified for an IPv6 address.

Essentially, this change provides the same DHCP support for IPv6
that has been available for IPv4.

With dnsmasq >= 2.64, support for the RA service is also now provided
by dnsmasq (radvd is no longer used/started). (Although at least one
version of dnsmasq prior to 2.64 "supported" IPv6 Router
Advertisement, there were bugs (fixed in 2.64) that rendered it
unusable.)

Documentation and the network schema has been updated
to reflect the new support.
2012-12-11 05:49:45 -05:00
Laine Stump
47c94b6563 conf: put data for network <forward> element into its own struct
The attributes of a <network> element's <forward> element were
previously stored directly in the virNetworkDef object, but
virNetworkUpdateForward() needs to operate on a <forward> in
isolation, so this patchs pulls out all those attributes into a
separate virNetworkForwardDef struct (and shortens their names
appropriately). This new object is contained in the virNetworkDef, not
pointed to by it, so there is no extra memory management.

This patch makes no functional changes, it only changes, e.g.,
"nForwardIfs" to "forward.nifs".
2012-12-11 05:49:44 -05:00
Laine Stump
ab297becc1 conf: clear and parse functions for dns host/srv/txt records
Since there is only a single virNetworkDNSDef for any virNetworkDef,
and it's trivial to determine whether or not it contains any real
data, it's much simpler (and fits more uniformly with the parse
function calling sequence of the parsers for many other objects that
are subordinates of virNetworkDef) if virNetworkDef *contains* an
virNetworkDNSDef rather than pointing to one.

Since it is now just a part of another object rather than its own
object, it no longer makes sense to have a *Free() function, so that
is changed to a *Clear() function.

More importantly though, ParseXML and Clear functions are needed for
the individual items contained in a virNetworkDNSDef (srv, txt, and
host records), but none of them have a *Clear(), and only two of the
three had *ParseXML() functions (both of which used a non-uniform
arglist). Those problems are cleared up by this patch - it splits the
higher-level Clear function into separate functions for each of the
three, creates a parse for txt records, and cleans up the srv and host
parsers, so we now have all the utility functions necessary to
implement virNetworkDefUpdateDNS(Host|Srv|Txt).
2012-12-11 05:49:44 -05:00
Laine Stump
8b7d187417 conf: rename network dns host/srv/txt arrays
This shortens the name of the structs for srv and txt, and their
instances in virNetworkDNSDef, to be more compact and uniform with the
naming of the dns host array. It also changes the type of ntxts, etc
from unsigned int to size_t, so that they can be used directly as args
to VIR_*_ELEMENT.
2012-12-11 05:49:44 -05:00
Laine Stump
fd54f1de53 network: prevent a few invalid configuration combinations
This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=767057

It was possible to define a network with <forward mode='bridge'> that
had both a bridge device and a forward device defined. These two are
mutually exclusive by definition (if you are using a bridge device,
then this is a host bridge, and if you have a forward dev defined,
this is using macvtap). It was also possible to put <ip>, <dns>, and
<domain> elements in this definition, although those aren't supported
by the current driver (although it's conceivable that some other
driver might support that).

The items that are invalid by definition, are now checked in the XML
parser (since they will definitely *always* be wrong), and the others
are checked in networkValidate() in the network driver (since, as
mentioned, it's possible that some other network driver, or even this
one, could some day support setting those).
2012-12-05 18:03:34 -05:00
Gene Czarcinski
705e67d40b network: allow guest to guest IPv6 without gateway definition
This patch adds the capability for virtual guests to do IPv6
communication via a virtual network interface with no IPv6 (gateway)
addresses specified.  This capability has always been enabled by
default for IPv4, but disabled for IPv6 for security concerns, and
because it requires the ip6tables command to be operational (which
isn't the case on a system with the ipv6 module completely disabled).

This patch adds a new attribute "ipv6" at the toplevel of a <network>
object.  If ipv6='yes', the extra ip6tables rules required to permite
inter-guest communications are added when the network is started. If
it is 'no', or not present, those rules will not be added; thus the
default behavior doesn't change, so there should be no compatibility
issues with any existing installations.

Note that virtual guests cannot communication with the virtualization
host via this interface, because the following kernel tunable has
been set:

   net.ipv6.conf.<bridge_interface_name>.disable_ipv6 = 1

This assures that the bridge interface will not have an IPv6
link-local (fe80::) address.

To control this behavior so that it is not enabled by default, the parameter
ipv6='yes' on the <network> statement has been added.

Documentation related to this patch has been updated.
The network schema has also been updated.
2012-12-05 14:58:32 -05:00
Daniel P. Berrange
79b8a56995 Replace polling for active VMs with signalling by drivers
Currently to deal with auto-shutdown libvirtd must periodically
poll all stateful drivers. Thus sucks because it requires
acquiring both the driver lock and locks on every single virtual
machine. Instead pass in a "inhibit" callback to virStateInitialize
which drivers can invoke whenever they want to inhibit shutdown
due to existance of active VMs.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-12-04 12:14:04 +00:00
Daniel P. Berrange
ae2163f852 Only let VM drivers block libvirtd timed shutdown
The only important state that should prevent libvirtd shutdown
is from running VMs. Networks, host devices, network filters
and storage pools are all long lived resources that have no
significant in-memory state. They should not block shutdown.
2012-12-04 12:12:51 +00:00
Laine Stump
753ff83a50 network: use dnsmasq --bind-dynamic when available
This bug resolves CVE-2012-3411, which is described in the following
bugzilla report:

  https://bugzilla.redhat.com/show_bug.cgi?id=833033

The following report is specifically for libvirt on Fedora:

  https://bugzilla.redhat.com/show_bug.cgi?id=874702

In short, a dnsmasq instance run with the intention of listening for
DHCP/DNS requests only on a libvirt virtual network (which is
constructed using a Linux host bridge) would also answer queries sent
from outside the virtualization host.

This patch takes advantage of a new dnsmasq option "--bind-dynamic",
which will cause the listening socket to be setup such that it will
only receive those requests that actually come in via the bridge
interface. In order for this behavior to actually occur, not only must
"--bind-interfaces" be replaced with "--bind-dynamic", but also all
"--listen-address" options must be replaced with a single
"--interface" option. Fully:

   --bind-interfaces --except-interface lo --listen-address x.x.x.x ...

(with --listen-address possibly repeated) is replaced with:

   --bind-dynamic --interface virbrX

Of course libvirt can't use this new option if the host's dnsmasq
doesn't have it, but we still want libvirt to function (because the
great majority of libvirt installations, which only have mode='nat'
networks using RFC1918 private address ranges (e.g. 192.168.122.0/24),
are immune to this vulnerability from anywhere beyond the local subnet
of the host), so we use the new dnsmasqCaps API to check if dnsmasq
supports the new option and, if not, we use the "old" option style
instead. In order to assure that this permissiveness doesn't lead to a
vulnerable system, we do check for non-private addresses in this case,
and refuse to start the network if both a) we are using the old-style
options, and b) the network has a publicly routable IP
address. Hopefully this will provide the proper balance of not being
disruptive to those not practically affected, and making sure that
those who *are* affected get their dnsmasq upgraded.

(--bind-dynamic was added to dnsmasq in upstream commit
54dd393f3938fc0c19088fbd319b95e37d81a2b0, which was included in
dnsmasq-2.63)
2012-11-29 15:02:39 -05:00
Laine Stump
719c2c7665 util: capabilities detection for dnsmasq
In order to optionally take advantage of new features in dnsmasq when
the host's version of dnsmasq supports them, but still be able to run
on hosts that don't support the new features, we need to be able to
detect the version of dnsmasq running on the host, and possibly
determine from the help output what options are in this dnsmasq.

This patch implements a greatly simplified version of the capabilities
code we already have for qemu. A dnsmasqCaps device can be created and
populated either from running a program on disk, reading a file with
the concatenated output of "dnsmasq --version; dnsmasq --help", or
examining a buffer in memory that contains the concatenated output of
those two commands. Simple functions to retrieve capabilities flags,
the version number, and the path of the binary are also included.

bridge_driver.c creates a single dnsmasqCaps object at driver startup,
and disposes of it at driver shutdown. Any time it must be used, the
dnsmasqCapsRefresh method is called - it checks the mtime of the
binary, and re-runs the checks if the binary has changed.

networkxml2argvtest.c creates 2 "artificial" dnsmasqCaps objects at
startup - one "restricted" (doesn't support --bind-dynamic) and one
"full" (does support --bind-dynamic). Some of the test cases use one
and some the other, to make sure both code pathes are tested.
2012-11-29 15:02:39 -05:00
Daniel P. Berrange
f4ea67f5b3 Turn some dual-state int parameters into booleans
The virStateInitialize method and several cgroups methods were
using an 'int privileged' parameter or similar for dual-state
values. These are better represented with the bool type.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-11-29 16:14:43 +00:00
Daniel P. Berrange
54f89ef1fc Change bridge driver to use named initializers with virDriverState
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2012-11-27 19:37:07 +00:00
Ján Tomko
5efacd7813 build: fix build --without-network
bridge_driver.h: silence gcc warnings:
statement with no effect [-Wunused-value]
unused variable 'net' [-Wunused-variable]

virdrivermoduletest.c: don't require network driver module
if it hasn't been built.
2012-11-26 14:01:23 +01:00
Daniel P. Berrange
1c04f99970 Remove spurious whitespace between function name & open brackets
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>
2012-11-02 13:36:49 +00:00
Peter Krempa
0211fd6e04 net: Mark network persistent when assigning persistent definition
When assigning the new persistent definition for a transient network
(thus making it persistent) the network needs to be marked persistent
before actually atempting to assign the definition.
2012-11-02 13:28:40 +01:00
Peter Krempa
fa16957ccd net: Add support for changing persistent networks to transient
Until now, the network undefine API was able to undefine only inactive
networks. The restriction doesn't make sense any more so this patch
implements changing networks to transient.
2012-11-02 13:28:40 +01:00
Peter Krempa
b6dbbae128 net: Re-use checks when creating transient networks
When a transient network was created some of the checks weren't run on
the definition allowing to start invalid networks.

This patch splits out code to the network validation function and
re-uses that code when creating transient networks.
2012-11-02 13:28:40 +01:00
Peter Krempa
e87af617fc net: Remove dnsmasq and radvd files also when destroying transient nets
The network driver didn't care about config files when a network was
destroyed, just when it was undefined leaving behind files for transient
networks.

This patch splits out the cleanup code to a helper function that handles
the cleanup if the inactive network object is being removed and re-uses
this code when getting rid of inactive networks.
2012-11-02 13:28:40 +01:00
Peter Krempa
23ae3fe425 net: Move creation of dnsmasq hosts file to function starting dnsmasq
The hosts file was created in the network definition function. This
patch moves the place the file is being created to the point where
dnsmasq is being started.
2012-11-02 13:28:40 +01:00
Peter Krempa
a3258c0eb9 net: Change argument type of virNetworkObjIsDuplicate()
The argument check_active is used only as a boolean so this patch
changes the type and updates callers.
2012-11-02 13:28:39 +01:00
Gene Czarcinski
adaa7ab653 bugfix: ip6tables rule removal
Three FORWARD chain rules are added and two INPUT chain rules
are added when a network is started but only the FORWARD chain
rules are removed when the network is destroyed.
2012-10-30 16:04:25 -06:00
Laine Stump
d8aae15aa1 network: fix networkValidate check for default portgroup and vlan
This was found during testing of the fix for:

   https://bugzilla.redhat.com/show_bug.cgi?id=868483

networkValidate was supposed to check for the existence of multiple
portgroups and report an error if this was encountered. It did, but
there were two problems:

1) even though it logged an error, it still returned success, allowing
the operation to continue.

2) It could exit the portgroup checking loop early (or possibly not
even do it once) if a vlan tag was supplied in the base network config
or one of the portgroups.

This patch fixes networkValidate to return failure in addition to
logging the error, and also changes it to not exit the portgroup
checking loop early. The logic was a bit off in the checking for vlan
anyway, and it's intertwined with fixing the early loop exit, so I
fixed that as well. Now it correctly checks for combinations where a
<virtualport> is specified in the base network def and <vlan> is given
in a portgroup, as well as the opposite (<vlan> in base network def
and <virtualport> in portgroup), and ignores the case of a disallowed
vlan when using *no* portgroup if there is a default portgroup (since
in that case there is no way to not use any portgroup).
2012-10-25 16:32:04 -04:00
Laine Stump
6f8a8b30c9 network: don't allow multiple default portgroups
This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=868483

virNetworkUpdate, virNetworkDefine, and virNetworkCreate all three
allow network definitions to contain multiple <portgroup> elements
with default='yes'. Only a single default portgroup should be allowed
for each network.

This patch updates networkValidate() (called by both
virNetworkCreate() and virNetworkDefine()) and
virNetworkDefUpdatePortGroup (called by virNetworkUpdate() to not
allow multiple default portgroups.
2012-10-20 21:29:19 -04:00
Laine Stump
1cb1f9dabf network: always create dnsmasq hosts and addnhosts files, even if empty
This fixes the problem reported in:

  https://bugzilla.redhat.com/show_bug.cgi?id=868389

Previously, the dnsmasq hosts file (used for static dhcp entries, and
addnhosts file (used for additional dns host entries) were only
created/referenced on the dnsmasq commandline if there was something
to put in them at the time the network was started. Once we can update
a network definition while it's active (which is now possible with
virNetworkUpdate), this is no longer a valid strategy - if there were
0 dhcp static hosts (resulting in no reference to the hosts file on the
commandline), then one was later added, the commandline wouldn't have
linked dnsmasq up to the file, so even though we create it, dnsmasq
doesn't pay any attention.

The solution is to just always create these files and reference them
on the dnsmasq commandline (almost always, anyway). That way dnsmasq
can notice when a new entry is added at runtime (a SIGHUP is sent to
dnsmasq by virNetworkUdpate whenever a host entry is added or removed)

The exception to this is that the dhcp static hosts file isn't created
if there are no lease ranges *and* no static hosts. This is because in
this case dnsmasq won't be setup to listen for dhcp requests anyway -
in that case, if the count of dhcp hosts goes from 0 to 1, dnsmasq
will need to be restarted anyway (to get it listening on the dhcp
port). Likewise, if the dhcp hosts count goes from 1 to 0 (and there
are no dhcp ranges) we need to restart dnsmasq so that it will stop
listening on port 67. These special situations are handled in the
bridge driver's networkUpdate() by checking for ((bool)
nranges||nhosts) both before and after the update, and triggering a
dnsmasq restart if the before and after don't match.
2012-10-20 21:29:19 -04:00
Laine Stump
78fab2770b network: free/null newDef if network fails to start
https://bugzilla.redhat.com/show_bug.cgi?id=866364

pointed out a crash due to virNetworkObjAssignDef free'ing
network->newDef without NULLing it afterward. A fix for this is in
upstream commit b7e9202401. While the
NULLing of newDef was a legitimate fix, newDef should have already
been empty (NULL) anyway (as indicated in the comment that was deleted
by that commit).

The reason that newDef had a non-NULL value (i.e. the root cause) was
that networkStartNetwork() had failed after populating
network->newDef, but then neglected to free/NULL newDef in the
cleanup.

(A bit of background here: network->newDef should contain the
persistent config of a network when a network is active (and of course
only when it is persisten), and NULL at all other times. There is also
a network->def which should contain the persistent definition of the
network when it is inactive, and the current live state at all other
times. The idea is that you can make changes to network->newDef which
will take effect the next time the network is restarted, but won't
mess with the current state of the network (virDomainObj has a similar
pair of virDomainDefs that behave in the same fashion). Personally I
think there should be a network->live and network->config, and the
location of the persistent config should *always* be in
network->config, but that's for a later cleanup).

Since I love things to be symmetric, I created a new function called
virNetworkObjUnsetDefTransient(), which reverses the effects of
virNetworkObjSetDefTransient(). I don't really like the name of the
new function, but then I also didn't really like the name of the old
one either (it's just named that way to match a similar function in
the domain conf code).
2012-10-20 02:43:16 -04:00
Eric Blake
2cfa14bc8a maint: drop spurious semicolons
Detected with:
git grep ';;$' -- '**/*.[ch]'

* src/network/bridge_driver.c (networkRadvdConfContents): Fix
harmless typo.
* src/phyp/phyp_driver.c (phypUUIDTable_Pull): Likewise.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDriveDel):
Likewise.
2012-10-15 09:08:19 -06:00
Laine Stump
310945597c conf: fix virDevicePCIAddressEqual args
This function really should have been taking virDevicePCIAddress*
instead of the inefficient virDevicePCIAddress (results in copying two
entire structs onto the stack rather than just two pointers), and
returning a bool true/false (not matching is not necessarily a
"failure", as a -1 return would imply, and also using "if
(!virDevicePCIAddressEqual(x, y))" to mean "if x == y" is just a bit
counterintuitive).
2012-10-15 04:03:06 -04:00
Benjamin Cama
db488c7917 network: fix dnsmasq/radvd binding to IPv6 on recent kernels
I hit this problem recently when trying to create a bridge with an IPv6
address on a 3.2 kernel: dnsmasq (and, further, radvd) would not bind to
the given address, waiting 20s and then giving up with -EADDRNOTAVAIL
(resp. exiting immediately with "error parsing or activating the config
file", without libvirt noticing it, BTW). This can be reproduced with (I
think) any kernel >= 2.6.39 and the following XML (to be used with
"virsh net-create"):

        <network>
          <name>test-bridge</name>
          <bridge name='testbr0' />
          <ip family='ipv6' address='fd00::1' prefix='64'>
          </ip>
        </network>

(it happens even when you have an IPv4, too)

The problem is that since commit [1] (which, ironically, was made to
“help IPv6 autoconfiguration”) the linux bridge code makes bridges
behave like “real” devices regarding carrier detection. This makes the
bridges created by libvirt, which are started without any up devices,
stay with the NO-CARRIER flag set, and thus prevents DAD (Duplicate
address detection) from happening, thus letting the IPv6 address flagged
as “tentative”. Such addresses cannot be bound to (see RFC 2462), so
dnsmasq fails binding to it (for radvd, it detects that "interface XXX
is not RUNNING", thus that "interface XXX does not exist, ignoring the
interface" (sic)). It seems that this behavior was enhanced somehow with
commit [2] by avoiding setting NO-CARRIER on empty bridges, but I
couldn't reproduce this behavior on my kernel. Anyway, with the “dummy
tap to set MAC address” trick, this wouldn't work.

To fix this, the idea is to get the bridge's attached device to be up so
that DAD can happen (deactivating DAD altogether is not a good idea, I
think). Currently, libvirt creates a dummy TAP device to set the MAC
address of the bridge, keeping it down. But even if we set this device
up, it is not RUNNING as soon as the tap file descriptor attached to it
is closed, thus still preventing DAD. So, we must modify the API a bit,
so that we can get the fd, keep the tap device persistent, run the
daemons, and close it after DAD has taken place. After that, the bridge
will be flagged NO-CARRIER again, but the daemons will be running, even
if not happy about the device's state (but we don't really care about
the bridge's daemons doing anything when no up interface is connected to
it).

Other solutions that I envisioned were:
      * Keeping the *-nic interface up: this would waste an fd for each
        bridge during all its life. May be acceptable, I don't really
        know.
      * Stop using the dummy tap trick, and set the MAC address directly
        on the bridge: it is possible since quite some time it seems,
        even if then there is the problem of the bridge not being
        RUNNING when empty, contrary to what [2] says, so this will need
        fixing (and this fix only happened in 3.1, so it wouldn't work
        for 2.6.39)
      * Using the --interface option of dnsmasq, but I saw somewhere
        that it's not used by libvirt for backward compatibility. I am
        not sure this would solve this problem, though, as I don't know
        how dnsmasq binds itself to it with this option.

This is why this patch does what's described earlier.

This patch also makes radvd start even if the interface is
“missing” (i.e. it is not RUNNING), as it daemonizes before binding to
it, and thus sometimes does it after the interface has been brought down
by us (by closing the tap fd), and then originally stops. This also
makes it stop yelling about it in the logs when the interface is down at
a later time.

[1]
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=1faa4356a3bd89ea11fb92752d897cff3a20ec0e
[2]
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=b64b73d7d0c480f75684519c6134e79d50c1b341
2012-09-27 11:17:52 -06:00
Laine Stump
36ba0ee7b9 network: don't "refresh" iptables rules on rule-less networks
The bridge driver implementation of virNetworkUpdate() removes and
re-adds iptables rules any time a network has an <ip>, <forward>, or
<forward>/<interface> element updated. There are some types of
networks that have those elements and yet have no iptables rules
associated with them, and unfortunately the functions that remove/add
iptables rules don't check the type of network before attempting to
remove/add the rules, sometimes leading to an erroneous failure of the
entire update operation.

Under normal circumstances I would refactor the lower level functions
to be more robust, but to avoid code churn as much as possible, I've
just added extra checks directly to networkUpdate().
2012-09-21 20:10:43 -04:00