This patch restores broken guest network connectivity after a host
firewalld is switched to using an nftables backend. It does this by
adding libvirt networks' bridge interfaces to the new "libvirt" zone
in firewalld.

After this patch, the bridge interface of any network created by
libvirt (when firewalld is active) will be added to the firewalld
zone called "libvirt" if it exists (regardless of the firewalld
backend setting). This behavior does *not* depend on whether or not
libvirt has installed the libvirt zone file (set with
"--with[out]-firewalld-zone" during the configure phase of the package
build).

If the libvirt zone doesn't exist (either because the package was
configured to not install it, or possibly it was installed, but
firewalld doesn't support rule priorities, resulting in a parse
error), the bridge will remain in firewalld's default zone, which
could be innocuous (in the case that the firewalld backend is
iptables, guest networking will still function properly with the
bridge in the default zone), or it could be disastrous (if the
firewalld backend is nftables, we can be assured that guest networking
will fail). In order to be unobtrusive in the former case, and
informative in the latter, when the libvirt zone doesn't exist we
then check the firewalld version to see if it's new enough to support
the nftables backend, and then if the backend is actually set to
nftables, before logging an error (and failing the net-start
operation, since the network couldn't possibly work anyway).

When the libvirt zone is used, network behavior is *slightly*
different from behavior of previous libvirt. In the past, libvirt
network behavior would be affected by the configuration of firewalld's
default zone (usually "public"), but now it is affected only by the
"libvirt" zone), and thus almost surely warrants a release note for
any distro upgrading to libvirt 5.1 or above. Although it's
unfortunate that we have to deal with a mandatory behavior change, the
architecture of multiple hooks makes it impossible to *not* change
behavior in some way, and the new behavior is arguably better (since
it will now be possible to manage access to the host from virtual
machines vs from public interfaces separately).

Creates-and-Resolves: https://bugzilla.redhat.com/1650320
Resolves: https://bugzilla.redhat.com/1638342Signed-off-by: NLaine Stump <laine@laine.org>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

In the past (when both libvirt and firewalld used iptables), if either
libvirt's rules *OR* firewalld's rules accepted a packet, it would
be accepted. This was because libvirt and firewalld rules were
processed during the same kernel hook, and a single ACCEPT result
would terminate the rule traversal and cause the packet to be
accepted.

But now firewalld can use nftables for its backend, while libvirt's
firewall rules are still using iptables; iptables rules are still
processed, but at a different time during packet processing
(i.e. during a different hook) than the firewalld nftables rules. The
result is that a packet must be accepted by *BOTH* the libvirt
iptables rules *AND* the firewalld nftable rules in order to be
accepted.

This causes pain because

1) libvirt always adds rules to permit DNS and DHCP (and sometimes
TFTP) from guests to the host network's bridge interface. But
libvirt's bridges are in firewalld's "default" zone (which is usually
the zone called "public"). The public zone allows ssh, but doesn't
allow DNS, DHCP, or TFTP. So even though libvirt's rules allow the
DHCP and DNS traffic, the firewalld rules (now processed during a
different hook) dont, thus guests connected to libvirt's bridges can't
acquire an IP address from DHCP, nor can they make DNS queries to the
DNS server libvirt has setup on the host. (This could be solved by
modifying the default firewalld zone to allow DNS and DHCP, but that
would open *all* interfaces in the default zone to those services,
which is most likely not what the host's admin wants.)

2) Even though libvirt adds iptables rules to allow forwarded traffic
to pass the iptables hook, firewalld's higher level "rich rules" don't
yet have the ability to configure the acceptance of forwarded traffic
(traffic that is going somewhere beyond the host), so any traffic that
needs to be forwarded from guests to the network beyond the host is
rejected during the nftables hook by the default zone's "default
reject" policy (which rejects all traffic in the zone not specifically
allowed by the rules in the zone, whether that traffic is destined to
be forwarded or locally received by the host).

libvirt can't send "direct" nftables rules (firewalld only supports
direct/passthrough rules for iptables), so we can't solve this problem
by just sending explicit nftables rules instead of explicit iptables
rules (which, if it could be done, would place libvirt's rules in the
same hook as firewalld's native rules, and thus eliminate the need for
packets to be accepted by both libvirt's and firewalld's own rules).

However, we can take advantage of a quirk in firewalld zones that have
a default policy of "accept" (meaning any packet that doesn't match a
specific rule in the zone will be *accepted*) - this default accept will
also accept forwarded traffic (not just traffic destined for the host).

Of course we don't want to modify firewalld's default zone in that
way, because that would affect the filtering of traffic coming into
the host from other interfaces using that zone. Instead, we will
create a new zone called "libvirt". The libvirt zone will have a
default policy of accept so that forwarded traffic can pass and list
specific services that will be allowed into the host from guests (DNS,
DHCP, SSH, and TFTP).

But the same default accept policy that fixes forwarded traffic also
causes *all* traffic from guest to host to be accepted. To close this
new hole, the libvirt zone can take advantage of a new feature in
firewalld (currently slated for firewalld-0.7.0) - priorities for rich
rules - to add a low priority rule that rejects all local traffic (but
leaves alone all forwarded traffic).

So, our new zone will start with a list of services that are allowed
(dhcp, dns, tftp, and ssh to start, but configurable via any firewalld
management application, or direct editing of the zone file in
/etc/firewalld/zones/libvirt.xml), followed by a low priority
<reject/> rule (to reject all other traffic from guest to host), and
finally with a default policy of accept (to allow forwarded traffic).

This patch only creates the zonefile for the new zone, and implements
a configure.ac option to selectively enable/disable installation of
the new zone. A separate patch contains the necessary code to actually
place bridge interfaces in the libvirt zone.

Why do we need a configure option to disable installation of the new
libvirt zone? It uses a new firewalld attribute that sets the priority
of a rich rule; this feature first appears in firewalld-0.7.0 (unless
it has been backported to am earlier firewalld by a downstream
maintainer). If the file were installed on a system with firewalld
that didn't support rule priorities, firewalld would log an error
every time it restarted, causing confusion and lots of extra bug
reports.

So we add two new configure.ac switches to avoid polluting the system
logs with this error on systems that don't support rule priorities -
"--with-firewalld-zone" and "--without-firewalld-zone". A package
builder can use these to include/exclude the libvirt zone file in the
installation. If firewalld is enabled (--with-firewalld), the default
is --with-firewalld-zone, but it can be disabled during configure
(using --without-firewalld-zone). Targets that are using a firewalld
version too old to support the rule priority setting in the libvirt
zone file can simply add --without-firewalld-zone to their configure
commandline.

These switches only affect whether or not the libvirt zone file is
*installed* in /usr/lib/firewalld/zones, but have no effect on whether
or not libvirt looks for a zone called libvirt and tries to use it.

NB: firewalld zones can only be added to the permanent config of
firewalld, and won't be loaded/enabled until firewalld is restarted,
so at package install/upgrade time we have to restart firewalld. For
rpm-based distros, this is done in the libvirt.spec file by calling
the %firewalld_restart rpm macro, which is a part of the
firewalld-filesystem package. (For distros that don't use rpm
packages, the command "firewalld-cmd --reload" will have the same
effect).
Signed-off-by: NLaine Stump <laine@laine.org>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

virFirewallDGetBackend() reports whether firewalld is currently using
an iptables or an nftables backend.

virFirewallDGetVersion() learns the version of the firewalld running
on this system and returns it as 1000000*major + 1000*minor + micro.

virFirewallDGetZones() gets a list of all currently active firewalld
zones.

virFirewallDInterfaceSetZone() sets the firewalld zone of the given
interface.

virFirewallDZoneExists() can be used to learn whether or not a
particular zone is present and active in firewalld.
Signed-off-by: NLaine Stump <laine@laine.org>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

In preparation for adding several other firewalld-specific functions,
separate the code that's unique to firewalld from the more-generic
"firewall" file.
Signed-off-by: NLaine Stump <laine@laine.org>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Support for firewalld is a feature that can be selectively enabled or
disabled (using --with-firewalld/--without-firewalld), not merely
something that must be accounted for in the code if it is present with
no exceptions. It is more consistent with other usage in libvirt to
use WITH_FIREWALLD rather than HAVE_FIREWALLD.
Signed-off-by: NLaine Stump <laine@laine.org>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1657468

Commit be1bb6c9 changed the way volumes were stored from a forward
linked list to a hash table. In doing so, it required that each vol
object would have 3 unique values as keys into tables - key, name,
and path. Due to how vHBA/NPIV LUNs are created/used this resulted
in a failure to utilize all the LUN's found during processing.

During virStorageBackendSCSINewLun processing fetch the key (or
serial value) for NPIV LUN's using virStorageFileGetNPIVKey which
will formulate a more unique key based on the serial value and
the port for the LUN.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
ACKed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The vHBA/NPIV LUNs created via the udev processing of the
VPORT_CREATE command end up using the same serial value
as seen/generated by the /lib/udev/scsi_id as returned
during virStorageFileGetSCSIKey. Therefore, in order to
generate a unique enough key to be used when adding the
LUN as a volume during virStoragePoolObjAddVol a more
unique key needs to be generated for an NPIV volume.

The problem is illustrated by the following example, where
scsi_host5 is a vHBA used with the following LUNs:

$ lsscsi -tg
...
[5:0:4:0]    disk    fc:0x5006016844602198,0x101f00  /dev/sdh   /dev/sg23
[5:0:5:0]    disk    fc:0x5006016044602198,0x102000  /dev/sdi   /dev/sg24
...

Calling virStorageFileGetSCSIKey would return:

/lib/udev/scsi_id --device /dev/sdh --whitelisted --replace-whitespace /dev/sdh
350060160c460219850060160c4602198
/lib/udev/scsi_id --device /dev/sdh --whitelisted --replace-whitespace /dev/sdi
350060160c460219850060160c4602198

Note that althrough /dev/sdh and /dev/sdi are separate LUNs, they
end up with the same serial number used for the vol->key value.
When virStoragePoolFCRefreshThread calls virStoragePoolObjAddVol
the second LUN fails to be added with the following message
getting logged:

    virHashAddOrUpdateEntry:341 : internal error: Duplicate key

To resolve this, virStorageFileGetNPIVKey will use a similar call
sequence as virStorageFileGetSCSIKey, except that it will add the
"--export" option to the call. This results in more detailed output
which needs to be parsed in order to formulate a unique enough key
to be used. In order to be unique enough, the returned value will
concatenate the target port as returned in the "ID_TARGET_PORT"
field from the command to the "ID_SERIAL" value.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
ACKed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Alter the code to use the virStorageFileGetSCSIKey helper
to fetch the unique key for the SCSI disk. Alter the logic
to follow the former code which would return a duplicate
of @dev when either the virCommandRun succeeded, but returned
an empty string or when WITH_UDEV was not true.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
ACKed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Alter the "real" code to return -2 on virCommandRun failure.
Alter the comments and function header to describe the function
and its returns.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
ACKed-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1503284

The way we currently start qemu from CPU affinity POV is as
follows:

  1) the child process is set affinity to all online CPUs (unless
  some vcpu pinning was given in the domain XML)

  2) Once qemu is running, cpuset cgroup is configured taking
  memory pinning into account

Problem is that we let qemu allocate its memory just anywhere in
1) and then rely in 2) to be able to move the memory to
configured NUMA nodes. This might not be always possible (e.g.
qemu might lock some parts of its memory) and is very suboptimal
(copying large memory between NUMA nodes takes significant amount
of time).

The solution is to set affinity to one of (in priority order):
  - The CPUs associated with NUMA memory affinity mask
  - The CPUs associated with emulator pinning
  - All online host CPUs

Later (once QEMU has allocated its memory) we then change this
again to (again in priority order):
  - The CPUs associated with emulator pinning
  - The CPUs returned by numad
  - The CPUs associated with vCPU pinning
  - All online host CPUs
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

This is mainly about /dev/sev and its default permissions 0600. Of
course, rule of 'tinfoil' would be that we can't trust anything, but the
probing code in QEMU is considered safe from security's perspective + we
can't create an udev rule for this at the moment, because ioctls and
file system permissions aren't cross-checked in kernel and therefore a
user with read permissions could issue a 'privileged' operation on SEV
which is currently only limited to root.

https://bugzilla.redhat.com/show_bug.cgi?id=1665400Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

The default permissions (0600 root:root) are of no use to the qemu
process so we need to change the owner to qemu iff running with
namespaces.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Instead of exposing /dev/sev to every domain, do it selectively.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

SEV has a limit on number of concurrent guests. From security POV we
should only expose resources (any resources for that matter) to domains
that truly need them.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

We should not give domains access to something they don't necessarily
need by default. Remove it from the qemu driver docs too.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Commit fb0d0d6c added capabilities data and updated
qemucapabilitiestest but forgot to update qemucaps2xmltest
at the same time.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

This shows users can now use PCI for RISC-V guests, as long
as they opt into it by manually assigning addresses.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

virtio-mmio is still used by default, so if PCI is desired
it's necessary to explicitly opt-in by adding an appropriate

  <address type='pci' domain='0x0000' ... />

element to the corresponding device.
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

This adds an additional directive to the dnsmasq configuration file that
notifies clients via dhcp about the link's MTU. Guests can then choose
adjust their link accordingly.
Signed-off-by: NCasey Callendrello <cdc@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>

This test relies on namespace support, which is only compiled in
if we have the 'fs' and 'netfs' backends.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

Instead of repeating the same platform for every test,
set it once, since we do the same tests with the same
input for all platforms, it's just the output that differs.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

Instead of a pair of bools.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

This was a left-over that should have been dropped along the change in
qemu.conf.
Signed-off-by: NErik Skultety <eskultet@redhat.com>

Only run the pool-netfs-ns-mountopts if built WITH_STORAGE_FS and only
run pool-rbd-ns-configopts if built with WITH_STORAGE_RBD since the
namespace support is only enabled if the pool is enabled.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>
Reviewed-by: NJán Tomko <jtomko@redhat.com>

The 'qemu' binary used to provide the i386 emulator until it was renamed
to qemu-system-i386 in QEMU 1.0. Since we don't support such old
versions we don't need to check for 'qemu' when probing capabilities.
Reviewed-by: NErik Skultety <eskultet@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The custom namespaces were originally registered against the storage
pool source struct, but during review this was changed to the top level
storage pool struct. The namespace URIs were not updated to match, so
had a redundant '/source' component.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Some clients poll virDomainGetBlockJobInfo rather than wait for the
VIR_DOMAIN_BLOCK_JOB_READY event. In some cases qemu can get to 100% and
still not reach the synchronised phase. Initiating a pivot in that case
will fail.

Given that computers are interacting here, the error that the job
can't be finalized yet is not handled very well by those specific
implementations.

Our docs now correctly state to use the event. We already do a similar
output adjustment in case when the progress is not available from qemu
as in that case we'd report 0 out of 0, which some apps also incorrectly
considered as 100% complete.

In this case we subtract 1 from the progress if the ready state is not
signalled by qemu if the progress was at 100% otherwise.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Bump the width to 70em while keeping a maximum width of 95% to allow for
some border.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

Big number itself does not make much sense in some cases. Format the
bitshift format as well.

Changes our web page docs from:

VIR_MIGRATE_POSTCOPY = 32768 : Setting the VIR_MIGRATE_POSTCOPY...
VIR_MIGRATE_TLS      = 65536 : Setting the VIR_MIGRATE_TLS flag...

to:

VIR_MIGRATE_POSTCOPY = 32768 (0x8000; 1 << 15)  : Setting the VIR_MIGRATE_POSTCOPY...
VIR_MIGRATE_TLS      = 65536 (0x10000; 1 << 16) : Setting the VIR_MIGRATE_TLS flag...
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

A copy+paste mistaken meant the wrong enum -> string convertor
function was used for the error when an incorrect feature capability was
used.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

PEP 8 says:

    "Comparisons to singletons like None should always be done
     with 'is' or 'is not', never the equality operators."

There are potentially semantics differences, though in the case of this
libvirt code its merely a style change:

  http://jaredgrubb.blogspot.com/2009/04/python-is-none-vs-none.htmlReviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The virDomainDeviceInfo parameter is a large struct so it is preferrable
to pass it by reference instead of by value.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The struct _virStorageBackendQemuImgInfo is quite large so it is
preferrable to pass it by reference instead of by value. This requires
us to stop modifying the "compat" field.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The 'rv' variable is never changed after being declared, so can be
removed.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

'val' is initialized from virDomainCapsFeatureTypeFromString and a
few lines earlier there was already a check for 'val < 0'.

The 'val >= 0' is thus always true. The enum conversion similarly
ensures that the val will be less than VIR_DOMAIN_CAPS_FEATURE_LAST,
so "val < VIR_DOMAIN_CAPS_FEATURE_LAST' is thus always true too.
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>