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: NPavel Hrdina <phrdina@redhat.com>
(cherry picked from commit 42000bf7)

Add check for more than one RTA_OIF, even though this is rather
unlikely.

Get rid of the buggy switch / break as this code won't need to
handle more attributes.

Use VIR_WARNINGS_NO_CAST_ALIGN to fix impossible to fix
util/virnetdevip.c:560:17: error: cast increases required alignment of target type [-Werror=cast-align]

(cherry picked from commit b202c39a)

The exact family of the socket created for the fd used by ioctl(7)
doesn't matter, it just needs to be a socket and not a file. But for
some reason when macvtap support was added, it used
AF_PACKET/SOCK_DGRAM sockets for its ioctls; we later used the same
AF_PACKET/SOCK_DGRAM socket for new ioctls we added, and eventually
modified the other pre-existing ioctl sockets (for creating/deleting
bridges) to also use AF_PACKET/SOCK_DGRAM (that code originally used
AF_UNIX/SOCK_STREAM).

The problem with using AF_PACKET (intended for sending/receiving "raw"
packets, i.e. packets that can be some protocol other than TCP or UDP)
is that it requires root privileges. This meant that none of the
ioctls in virnetdev.c or virnetdevip.c would work when running
libvirtd unprivileged.

This packet solves that problem by changing the family to AF_UNIX when
creating the socket used for any ioctl().

When enabling IPv6 on all interfaces, we may get the host Router
Advertisement routes discarded. To avoid this, the user needs to set
accept_ra to 2 for the interfaces with such routes.

See https://www.kernel.org/doc/Documentation/networking/ip-sysctl.txt
on this topic.

To avoid user mistakenly losing routes on their hosts, check
accept_ra values before enabling IPv6 forwarding. If a RA route is
detected, but neither the corresponding device nor global accept_ra
is set to 2, the network will fail to start.

After freeing the data structures we have to reset the counters to
zero. This fixes a segmentation fault when virNetDevIPInfoClear is
called twice (e.g. this is possible in virDomainNetDefParseXML() if
virDomainNetIPInfoParseXML(...) fails with ret < 0 (this leads to the
first call of 'virNetDevIPInfoClear(&def->guestIP)') and the resulting
call of virDomainNetDefFree(def) in the error path of
virDomainNetDefParseXML() (this leads to the second call of
virNetDevIPInfoClear(&def->guestIP), and finally to the segmentation
fault).
Signed-off-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NBoris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: NBjoern Walk <bwalk@linux.vnet.ibm.com>

This will apply to any IP address setting that uses
virNetDevIPInfoAddToDev() (which so far is only the guest-side of LXC
type='ethernet' interfaces).

(This patch had been pushed earlier in
commit cb20f989, but was reverted in
commit cba06aea because it had been
accidentally pushed during the freeze for release 2.0.0)

This patch takes the code out of
lxcContainerRenameAndEnableInterfaces() that adds all IP addresses and
IP routes to the interface, and puts it into a utility function
virNetDevIPInfoAddToDev() in virnetdevip.c so that it can be used by
anyone.

One small change in functionality -
lxcContainerRenameAndEnableInterfaces() previously would add all IP
addresses to the interface while it was still offline, then set the
interface online, and then add the routes. Because I don't want the
utility function to set the interface online, I've moved this up so
the interface is first set online, then IP addresses and routes are
added. This is the same order that the network service from
initscripts (in ifup-ether) does it, so it shouldn't pose any problem
(and hasn't, in the tests that I've run).

(This patch had been pushed earlier in commit
f1e0d0da, but was reverted in commit
05eab475 because it had been
accidentally pushed during the freeze for release 2.0.0)

This reverts commit f1e0d0da.

This feature was accidentally pushed in the feature freeze.

This reverts commit cb20f989.

This feature was accidentally pushed in the feature freeze.

Commit cf0568b0 moved a bunch of functions from virNetDev
to the more specific virNetDevIP; however, not all of the
existing uses were moved properly, causing build failures on
FreeBSD.

Complete the transition to the new names and drop the
obsolete declarations from the header file while at it.

Not including the header causes

  util/virnetdevip.c:520:5: error:
  unknown type name 'virCommandPtr'; did you mean 'virCondPtr'?
    virCommandPtr cmd = NULL;
    ^~~~~~~~~~~~~

and plenty more similar failures when compiling on FreeBSD.

This will apply to any IP address setting that uses
virNetDevIPInfoAddToDev() (which so far is only the guest-side of LXC
type='ethernet' interfaces).

This patch takes the code out of
lxcContainerRenameAndEnableInterfaces() that adds all IP addresses and
IP routes to the interface, and puts it into a utility function
virNetDevIPInfoAddToDev() in virnetdevip.c so that it can be used by
anyone.

One small change in functionality -
lxcContainerRenameAndEnableInterfaces() previously would add all IP
addresses to the interface while it was still offline, then set the
interface online, and then add the routes. Because I don't want the
utility function to set the interface online, I've moved this up so
the interface is first set online, then IP addresses and routes are
added. This is the same order that the network service from
initscripts (in ifup-ether) does it, so it shouldn't pose any problem
(and hasn't, in the tests that I've run).

It makes more sense to have the logging at the lower level so other
callers can share the goodness.

While removing so much stuff from / touching so many lines in
lxcContainerRenameAndEnableInterfaces() (which used to have this
debug/error logging), label names were changed and it was updated to
use the now-more-common method of initializing ret to -1 (failure),
then setting to 0 right before the cleanup label.

There are currently two places in the domain where this combination is
used, and there is about to be another. This patch puts them together
for brevity and uniformity.

As with the newly-renamed virNetDevIPAddr and virNetDevIPRoute
objects, the new virNetDevIPInfo object will need to be accessed by a
utility function that calls low level Netlink functions (so we don't
want it to be in the conf directory) and will be called from multiple
hypervisor drivers (so it can't be in any hypervisor directory); the
most appropriate place is thus once again the util directory.

The parse and format functions are in conf/domain_conf.c because only
the domain XML (i.e. *not* the network XML) has this exact combination
of IP addresses plus routes. Note that virDomainNetIPInfoFormat() will
end up being the only caller to virDomainNetRoutesFormat() and
virDomainNetIPsFormat(), so it will just subsume those functions in a
later patch, but we can't do that until they are no longer called.

(It would have been nice to include the interface name within the
virNetDevIPInfo object (with a slight name change), but that can't
be done cleanly, because in each case the interface name is provided
in a different place in the XML relative to the routes and IP
addresses, so putting it in this object would actually make the code
more confused rather than simpler).

These functions all need to be called from a utility function that
must be located in the util directory, so we move them all into
util/virnetdevip.[ch] now that it exists.

Function and struct names were appropriately changed for the new
location, but all code is unchanged aside from motion and renaming.

This patch splits virnetdev.[ch] into multiple files, with the new
virnetdevip.[ch] containing all the functions related to setting and
retrieving IP-related info for a device (both addresses and routes).