Commit Graph

64 Commits

Author SHA1 Message Date
Daniel P. Berrangé
de938b92c9 util: add helper method for re-attaching a tap device to a bridge
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-04-16 14:44:53 +01:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Erik Skultety
5165ff0971 src: More cleanup of some system headers already contained in internal.h
All of the ones being removed are pulled in by internal.h. The only
exception is sanlock which expects the application to include <stdint.h>
before sanlock's headers, because sanlock prototypes use fixed width
int, but they don't include stdint.h themselves, so we have to leave
that one in place.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-20 10:16:39 +02:00
Erik Skultety
9403b63102 internal: Move <stdio.h> include to internal.h
It doesn't really make sense for us to have stdlib.h and string.h but
not stdio.h in the internal.h header.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Acked-by: Michal Privoznik <mprivozn@redhat.com>
2018-09-20 10:16:38 +02:00
Sukrit Bhatnagar
f84b0f1499 util: netdevtap: use VIR_AUTOFREE instead of VIR_FREE for scalar types
By making use of GNU C's cleanup attribute handled by the
VIR_AUTOFREE macro for declaring scalar variables, majority
of the VIR_FREE calls can be dropped, which in turn leads to
getting rid of most of our cleanup sections.

Signed-off-by: Sukrit Bhatnagar <skrtbhtngr@gmail.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-08-07 16:29:55 +02:00
Andrea Bolognani
6c0d0210cb src: Make virStr*cpy*() functions return an int
Currently, the functions return a pointer to the
destination buffer on success or NULL on failure.

Not only does this kind of error handling look quite
alien in the context of libvirt, where most functions
return zero on success and a negative int on failure,
but it's also somewhat pointless because unless there's
been a failure the returned pointer will be the same
one passed in by the user, thus offering no additional
value.

Change the functions so that they return an int
instead.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2018-07-23 14:27:30 +02:00
Michal Privoznik
318d54e520 virnetdevtap: Don't crash on !ifname in virNetDevTapInterfaceStats
https://bugzilla.redhat.com/show_bug.cgi?id=1595184

Some domain <interfaces/> do not have a name (because they are
not TAP devices). Therefore, if
virNetDevTapInterfaceStats(net->ifname, ...) is called an instant
crash occurs. In Linux version of the function strlen() is called
over the name and in BSD version STREQ() is called.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2018-07-13 15:38:41 +02:00
Roman Bogorodskiy
3b90d0dc1a util: improve virNetDevTapGetRealDeviceName
virNetDevTapGetRealDeviceName() is used on FreeBSD because interface
names (such as one sees in output of tools like ifconfig(8)) might not
match their /dev entity names, and for bhyve we need the latter.

Current implementation is not very efficient because in order to find
/dev name, it goes through all /dev/tap* entries and tries to issue
TAPGIFNAME ioctl on it. Not only this is slow, but also there's a bug in
this implementation when more than one NIC is passed to a VM: once we
find the tap interface we're looking for, we set its state to UP because
opening it for issuing ioctl sets it DOWN, even if it was UP before.
When we have more than 1 NIC for a VM, we have only last one UP because
others remain DOWN after unsuccessful attempts to match interface name.

New implementation just uses sysctl(3), so it should be faster and
won't make interfaces go down to get name.

Signed-off-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2018-04-24 21:08:19 +04:00
Michal Privoznik
d86fd2402e virNetDevTapInterfaceStats: Allow caller to not swap the statistics
https://bugzilla.redhat.com/show_bug.cgi?id=1497410

The comment in virNetDevTapInterfaceStats() implementation for
Linux states that packets transmitted by domain are received by
the host and vice versa. Well, this is true but not for all types
of interfaces. For instance, for macvtaps when TAP device is
hooked right onto a physical device any packet that domain sends
looks also like a packet sent to the host. Therefore, we should
allow caller to chose if the stats returned should be straight
copy or swapped.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2017-10-05 09:16:05 +02:00
Martin Kletzander
307a205e25 qemu: Allow live-updates of coalesce settings
Change the settings from qemuDomainUpdateDeviceLive() as otherwise the
call would succeed even though nothing has changed.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1414627

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-06-16 10:18:35 +02:00
Martin Kletzander
fcef44728d Set coalesce settings for domain interfaces
This patch makes use of the virNetDevSetCoalesce() function to make
appropriate settings effective for devices that support them.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1414627

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-04-21 13:35:04 +02:00
Pavel Hrdina
42000bf7e5 util: check ifa_addr pointer before accessing its elements
Reported by Rafał Wojciechowski <it@rafalwojciechowski.pl>.

Thread 1 (Thread 0x7f194b99d700 (LWP 5631)):
0  virNetDevGetifaddrsAddress (addr=0x7f194b99c7c0, ifname=0x7f193400e2b0 "ovirtmgmt") at util/virnetdevip.c:738
1  virNetDevIPAddrGet (ifname=0x7f193400e2b0 "ovirtmgmt", addr=addr@entry=0x7f194b99c7c0) at util/virnetdevip.c:795
2  0x00007f19467800d6 in networkGetNetworkAddress (netname=<optimized out>, netaddr=netaddr@entry=0x7f1924013f18) at network/bridge_driver.c:4780
3  0x00007f193e43a33c in qemuProcessGraphicsSetupNetworkAddress (listenAddr=0x7f19340f7650 "127.0.0.1", glisten=0x7f1924013f10) at qemu/qemu_process.c:4062
4  qemuProcessGraphicsSetupListen (vm=<optimized out>, graphics=0x7f1924014f10, cfg=0x7f1934119f00) at qemu/qemu_process.c:4133
5  qemuProcessSetupGraphics (flags=17, vm=0x7f19240155d0, driver=0x7f193411f1d0) at qemu/qemu_process.c:4196
6  qemuProcessPrepareDomain (conn=conn@entry=0x7f192c00ab50, driver=driver@entry=0x7f193411f1d0, vm=vm@entry=0x7f19240155d0, flags=flags@entry=17) at qemu/qemu_process.c:4969
7  0x00007f193e4417c0 in qemuProcessStart (conn=conn@entry=0x7f192c00ab50, driver=driver@entry=0x7f193411f1d0, vm=0x7f19240155d0,asyncJob=asyncJob@entry=QEMU_ASYNC_JOB_START, migrateFrom=migrateFrom@entry=0x0, migrateFd=migrateFd@entry=-1, migratePath=migratePath@entry=0x0,snapshot=snapshot@entry=0x0, vmop=vmop@entry=VIR_NETDEV_VPORT_PROFILE_OP_CREATE, flags=17, flags@entry=1) at qemu/qemu_process.c:5553

Man page for getifaddrs also states that the "ifa_addr" may contain
a null pointer which happens if there is an existing network interface
on the host without IP address.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2017-04-21 11:05:18 +02:00
Laine Stump
a454134951 util: new function virNetDevTapAttachBridge()
This patch splits out the part of virNetDevTapCreateInBridgePort()
that would need to be re-done if an existing tap device had to be
re-attached to a bridge, and puts it into a separate function. This
can be used both when an existing domain interface config is updated
to change its connection, and also to re-attach to the "same" bridge
when a network has been stopped and restarted. So far it is used for
nothing.
2017-03-22 12:16:51 -04:00
Laine Stump
dd8ac030fb util: add MTU arg to virNetDevTapCreateInBridgePort()
virNetDevTapCreateInBridgePort() has always set the new tap device to
the current MTU of the bridge it's being attached to. There is one
case where we will want to set the new tap device to a different
(usually larger) MTU - if that's done with the very first device added
to the bridge, the bridge's MTU will be set to the device's MTU. This
patch allows for that possibility by adding "int mtu" to the arg list
for virNetDevTapCreateInBridgePort(), but all callers are sending -1,
so it doesn't yet have any effect.

Since the requested MTU isn't necessarily what is used in the end (for
example, if there is no MTU requested, the tap device will be set to
the current MTU of the bridge), and the hypervisor may want to know
the actual MTU used, we also return the actual MTU to the caller (if
actualMTU is non-NULL).
2017-02-07 13:45:08 -05:00
Mehdi Abaakouk
e0d893e86d Move virstat.c code to virnetdevtap.c
This is just a code move of virstat.c to virnetdevtap.c
2016-12-09 10:28:07 +01:00
Roman Bogorodskiy
b5447e78b2 util: fix build in virNetDevTapGetRealDeviceName
Commit e81de04c switched virNetDevTapGetRealDeviceName() to use
virDirOpen() instead of opendir(), however it mistakenly dropped
DIR *dirp declaration, so restore that to fix build.
2016-06-24 21:41:43 +03:00
Ján Tomko
e81de04c10 Use virDirOpen
Switch from opendir to virDirOpen everywhere we need to report an error.
2016-06-24 14:20:57 +02:00
Ján Tomko
a4e6f1eb9c Introduce VIR_DIR_CLOSE
Introduce a helper that only calls closedir if DIR* is non-NULL
and sets it to NULL afterwards.
2016-06-23 21:58:33 +02:00
Antoni Segura Puimedon
d490f47ba3 network: Add midonet virtual port type support to qemu
Use the utilities introduced in the previous patches so the qemu
driver is able to create tap devices that are bound (and unbound
on domain destroyal) to Midonet virtual ports.

Signed-off-by: Antoni Segura Puimedon <toni+libvirt@midokura.com>
2015-03-17 13:10:17 -04:00
Daniel P. Berrange
c5b6a4a5cb Change int to size_t in size var for tap/vhost FDs
A number of methods take an int for a parameter that indicates
the size of an array. The correct type for array sizes is
size_t
2015-01-15 11:07:13 +00:00
Martin Kletzander
1b7f8ca6bd Remove unnecessary curly brackets in src/util/
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-11-14 17:13:35 +01:00
Ján Tomko
b20d39a56f Wire up the interface backend options
Pass the user-specified tun path down when creating tap device
when called from the qemu driver.

Also honor the vhost device path specified by user.
2014-09-16 16:02:34 +02:00
Ján Tomko
f8a33815d0 Report correct error in virNetDevTapCreate
ioctl returns -1, not the errno value
2014-06-23 14:16:23 +02:00
Eric Blake
ac1d42ac72 util: use virDirRead API
In making the conversion to the new API, I fixed a couple bugs:
virSCSIDeviceGetSgName would leak memory if a directory
unexpectedly contained multiple entries;
virNetDevTapGetRealDeviceName could report a spurious error
from a stale errno inherited before starting the readdir search.

The decision on whether to store the result of virDirRead into
a variable is based on whether the end of the loop falls through
to cleanup code automatically.  In some cases, we have loops that
are documented to return NULL on failure, and which raise an
error on most failure paths but not in the case where the directory
was unexpectedly empty; it may be worth a followup patch to
explicitly report an error if readdir was successful but the
directory was empty, so that a NULL return always has an error set.

* src/util/vircgroup.c (virCgroupRemoveRecursively): Use new
interface.
(virCgroupKillRecursiveInternal, virCgroupSetOwner): Report
readdir failures.
* src/util/virfile.c (virFileLoopDeviceOpenSearch)
(virFileNBDDeviceFindUnused, virFileDeleteTree): Use new
interface.
* src/util/virnetdevtap.c (virNetDevTapGetRealDeviceName):
Properly check readdir errors.
* src/util/virpci.c (virPCIDeviceIterDevices)
(virPCIDeviceFileIterate, virPCIGetNetName): Report readdir
failures.
(virPCIDeviceAddressIOMMUGroupIterate): Use new interface.
* src/util/virscsi.c (virSCSIDeviceGetSgName): Report readdir
failures, and avoid memory leak.
(virSCSIDeviceGetDevName): Report readdir failures.
* src/util/virusb.c (virUSBDeviceSearch): Report readdir
failures.
* src/util/virutil.c (virGetFCHostNameByWWN)
(virFindFCHostCapableVport): Report readdir failures.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-04-28 17:52:45 -06:00
Roman Bogorodskiy
a1bd8d2546 Move virBhyveTapGetRealDeviceName to virnetdevtap
To ease mocking for bhyve unit tests move virBhyveTapGetRealDeviceName()
out of bhyve_command.c to virnetdevtap and rename it to
virNetDevTapGetRealDeviceName().
2014-03-27 08:23:58 +04:00
Ján Tomko
bada4222e5 Indent top-level labels by one space in src/util/ 2014-03-25 14:58:40 +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
Eric Blake
955af4d4c1 maint: avoid 'const fooPtr' in virnet files
'const fooPtr' is the same as 'foo * const' (the pointer won't
change, but it's contents can).  But in general, if an interface
is trying to be const-correct, it should be using 'const foo *'
(the pointer is to data that can't be changed).

Fix up remaining offenders in src/util.

* src/util/virnetdev.h (virNetDevSetMAC)
(virNetDevReplaceMacAddress, virNetDevValidateConfig)
(virNetDevReplaceNetConfig): Use intended type.
* src/util/virnetdevbandwidth.h (virNetDevBandwidthCopy)
(virNetDevBandwidthPlug): Likewise.
* src/util/virnetdevmacvlan.h (virNetDevMacVLanCreate)
(virNetDevMacVLanCreateWithVPortProfile)
(virNetDevMacVLanDeleteWithVPortProfile)
(virNetDevMacVLanRestartWithVPortProfile)
(virNetDevMacVLanVPortProfileRegisterCallback): Likewise.
* src/util/virnetdevopenvswitch.h (virNetDevOpenvswitchAddPort):
Likewise.
* src/util/virnetdevtap.h (virNetDevTapCreateInBridgePort):
Likewise.
* src/util/virnetdevvlan.h (virNetDevVlanEqual)
(virNetDevVlanCopy): Likewise.
* src/util/virnetdevvportprofile.h
(virNetDevVPortProfileAssociate)
(virNetDevVPortProfileDisassociate): Likewise.
* src/util/virnetlink.h (virNetlinkEventRemoveCallback)
(virNetlinkEventAddClient, virNetlinkEventRemoveClient):
Likewise.
* src/util/virnetdev.c (virNetDevSetMAC)
(virNetDevReplaceMacAddress, virNetDevValidateConfig)
(virNetDevReplaceNetConfig): Fix fallout.
* src/util/virnetdevbandwidth.c (virNetDevBandwidthCopy)
(virNetDevBandwidthPlug): Likewise.
* src/util/virnetdevmacvlan.c (virNetDevMacVLanCreate)
(virNetDevMacVLanCreateWithVPortProfile)
(virNetDevMacVLanDeleteWithVPortProfile)
(virNetDevMacVLanRestartWithVPortProfile)
(virNetDevMacVLanVPortProfileRegisterCallback): Likewise.
* src/util/virnetdevopenvswitch.c (virNetDevOpenvswitchAddPort):
Likewise.
* src/util/virnetdevtap.c (virNetDevTapCreateInBridgePort):
Likewise.
* src/util/virnetdevvlan.c (virNetDevVlanEqual)
(virNetDevVlanCopy): Likewise.
* src/util/virnetdevvportprofile.c
(virNetDevVPortProfileAssociate)
(virNetDevVPortProfileDisassociate)
(virNetDevVPortProfileOpSetLink, virNetDevVPortProfileOpCommon)
(virNetDevVPortProfileOp8021Qbg, virNetDevVPortProfileOp8021Qbh):
Likewise.
* src/util/virnetlink.c (virNetlinkEventRemoveCallback)
(virNetlinkEventAddClient, virNetlinkEventRemoveClient):
Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-10-14 13:05:34 -06:00
Michal Privoznik
1dc5dea7d6 qemu: Handle huge number of queues correctly
Currently, kernel supports up to 8 queues for a multiqueue tap device.
However, if user tries to enter a huge number (e.g. one million) the tap
allocation fails, as expected. But what is not expected is the log full
of warnings:

    warning : virFileClose:83 : Tried to close invalid fd 0

The problem is, upon error we iterate over an array of FDs (handlers to
queues) and VIR_FORCE_CLOSE() over each item. However, the array is
pre-filled with zeros. Hence, we repeatedly close stdin. Ouch.
But there's more. The queues allocation is done in virNetDevTapCreate()
which cleans up the FDs in case of error. Then, its caller, the
virNetDevTapCreateInBridgePort() iterates over the FD array and tries to
close them too. And so does qemuNetworkIfaceConnect() and
qemuBuildInterfaceCommandLine().
2013-09-03 13:38:35 +02:00
Daniel P. Berrange
f8b42f3224 Convert 'int i' to 'size_t i' in src/util/ 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 17:40:13 +01:00
Michal Privoznik
a2f8babc7d Adapt to VIR_ALLOC and virAsprintf in src/util/* 2013-07-10 11:07:33 +02:00
Daniel P. Berrange
002c8af9f0 Conditionalize use of IF_MAXUNIT in virnetdevtap.c
The IF_MAXUNIT macro is not present on all BSDs, so
make its use conditional, to avoid breaking OS-X.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2013-06-28 15:17:41 +01:00
Roman Bogorodskiy
847e1cd1f8 BSD: implement virNetDevTapCreate() and virNetDevTapDelete()
Implementation uses SIOCIFCREATE2 and SIOCIFDESTROY ioctls.
2013-06-14 16:44:31 +02:00
Michal Privoznik
f48ba88b35 Adapt to VIR_STRDUP and VIR_STRNDUP in src/util/* 2013-05-24 10:10:03 +02:00
Michal Privoznik
25a2d944df virNetDevTapCreate: Fail on systems not supporting IFF_MULTI_QUEUE
In my previous patches I enabled the IFF_MULTI_QUEUE flag every
time the user requested multiqueue TAP device. However, this
works only at runtime. During build time the flag may be
undeclared.
2013-05-22 18:32:27 +02:00
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
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
Eric Blake
b376dea91f build: mark conditionally unused variables
These fixes solve a compilation failure on FreeBSD:

util/virnetdevtap.c: In function 'virNetDevTapGetName':
util/virnetdevtap.c:56: warning: unused parameter 'tapfd' [-Wunused-parameter]
util/virnetdevtap.c:56: warning: unused parameter 'ifname' [-Wunused-parameter]

* src/util/virnetdevtap.c (virNetDevTapGetName): Add attributes
when TUNGETIFF is not present.

Signed-off-by: Eric Blake <eblake@redhat.com>
2013-04-30 08:21:26 -06:00
Paolo Bonzini
740d98a17d virnetdevtap: add virNetDevTapGetName
This will be used on a tap file descriptor returned by the bridge helper
to populate the <target> element, because the helper does not provide
the interface name.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-26 15:37:15 -06:00
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
Peter Krempa
6bd94a1b59 Use virMacAddrFormat instead of manual mac address formatting
Format the address using the helper instead of having similar code in
multiple places.

This patch also fixes leak of the MAC address string in
ebtablesRemoveForwardAllowIn() and ebtablesAddForwardAllowIn() in
src/util/virebtables.c
2013-04-02 15:53:43 +02:00
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
44f6ae27fe Rename util.{c,h} to virutil.{c,h} 2012-12-21 11:19:49 +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
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
Eric Blake
4ecb723b9e maint: fix up copyright notice inconsistencies
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/
2012-09-20 16:30:55 -06:00
Eric Blake
ccaf0beec8 build: improved handling of <execinfo.h>, BSD <net/if.h>
FreeBSD and OpenBSD have a <net/if.h> that is not self-contained;
and mingw lacks the header altogether.  But gnulib has just taken
care of that for us, so we might as well simplify our code.  In
the process, I got a syntax-check failure if we don't also take
the gnulib execinfo module.

* .gnulib: Update to latest, for execinfo and net_if.
* bootstrap.conf (gnulib_modules): Add execinfo and net_if modules.
* configure.ac: Let gnulib check for headers.  Simplify check for
'struct ifreq', while also including enough prereq headers.
* src/internal.h (IF_NAMESIZE): Drop, now that gnulib guarantees it.
* src/nwfilter/nwfilter_learnipaddr.h: Use correct header for
IF_NAMESIZE.
* src/util/virnetdev.c (includes): Assume <net/if.h> exists.
* src/util/virnetdevbridge.c (includes): Likewise.
* src/util/virnetdevtap.c (includes): Likewise.
* src/util/logging.c (includes): Assume <execinfo.h> exists.
(virLogStackTraceToFd): Handle gnulib's fallback implementation.
2012-09-06 10:08:47 -06:00
Kyle Mestery
7d2b91b86a network: add support for setting VLANs on Open vSwitch ports
Add the ability to support VLAN tags for Open vSwitch virtual port
types. To accomplish this, modify virNetDevOpenvswitchAddPort and
virNetDevTapCreateInBridgePort to take a virNetDevVlanPtr
argument. When adding the port to the OVS bridge, setup either a
single VLAN or a trunk port based on the configuration from the
virNetDevVlanPtr.

Signed-off-by: Kyle Mestery <kmestery@cisco.com>
2012-08-17 11:12:29 -04:00
Guannan Ren
72e59a3b74 util: Fix typoes on return value and comments
virNetDevTapCreateInBridgePort: Fix return value to -1
virNetDevTapCreate: Fix comments
2012-07-25 18:05:38 +08:00