When QEMU uid/gid is set to non-root this is pointless as if we just
used a regular setuid/setgid call, the process will have all its
capabilities cleared anyway by the kernel.
When QEMU uid/gid is set to root, this is almost (always?) never
what people actually want. People make QEMU run as root in order
to access some privileged resource that libvirt doesn't support
yet and this often requires capabilities. As a result they have
to go find the qemu.conf param to turn this off. This is not
viable for libguestfs - they want to control everything via the
XML security label to request running as root regardless of the
qemu.conf settings for user/group.
Clearing capabilities was implemented originally because there
was a proposal in Fedora to change permissions such that root,
with no capabilities would not be able to compromise the system.
ie a locked down root account. This never went anywhere though,
and as a result clearing capabilities when running as root does
not really get us any security benefit AFAICT. The root user
can easily do something like create a cronjob, which will then
faithfully be run with full capabilities, trivially bypassing
the restriction we place.
IOW, our clearing of capabilities is both useless from a security
POV, and breaks valid use cases when people need to run as root.
This removes the clear_emulator_capabilities configuration
option from qemu.conf, and always runs QEMU with capabilities
when root. The behaviour when non-root is unchanged.
Reviewed-by: Cole Robinson <crobinso@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Avoid grabbing the whole virCapsPtr object when we only need the
host CPU information.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Avoid grabbing the whole virCapsPtr object when we only need the
NUMA information.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Instead of using the virCapsPtr to get the default security model,
pass this in via the parser config.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
As part of a goal to eliminate the need to use virCapsPtr for anything
other than the virConnectGetCapabilies() API impl, cache the host arch
against the QEMU driver struct and use that field directly.
In the tests we move virArchFromHost() globally in testutils.c so that
every test runs with a fixed default architecture reported.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This previous commit introduced a simpler free callback for
hash data with only 1 arg, the value to free:
commit 49288fac965f0ee23db45d83ae4ef3a9a71dafd0
Author: Peter Krempa <pkrempa@redhat.com>
Date: Wed Oct 9 15:26:37 2019 +0200
util: hash: Add possibility to use simpler data free function in virHash
It missed two functions in the hash table code which need
to call the alternate data free function, virHashRemoveEntry
and virHashRemoveSet.
After the previous patch though, there is no code that
makes functional use of the 2nd key arg in the data
free function. There is merely one log message that can
be dropped.
We can thus purge the current virHashDataFree callback
entirely, and rename virHashDataFreeSimple to replace
it.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Libvirt currently uses the VIR_AUTOUNREF macro for auto cleanup of
virObject instances. GLib approaches things differently with GObject,
reusing their g_autoptr() concept.
This introduces support for g_autoptr() with virObject, to facilitate
the conversion to GObject.
Only virObject classes which are currently used with VIR_AUTOREF are
updated. Any others should be converted to GObject before introducing
use of autocleanup.
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
A slirp helper is a process that provides user-mode networking through
a unix domain socket. It is expected to follow the following
specification:
https://gitlab.freedesktop.org/slirp/libslirp-rs/blob/master/src/bin/README.rst
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
For now it's just a helper for building a qemu virDomainCapsPtr,
used in qemuConnectGetDomainCapabilities
Reviewed-by: Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
This is similar to the existing directory for snapshots; the domain
will save one xml file per checkpoint, for reloading on the next
libvirtd restart. Fortunately, since checkpoints mandate RNG
validation, we are assured that the checkpoint name will be usable as
a file name (no abuse of '../escape' as a checkpoint name, for
example).
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Some VM configurations may result in a large number of threads created by
the associated qemu process which can exceed the system default limit. The
maximum number of threads allowed per process is controlled by the pids
cgroup controller and is set to 16k when creating VMs with systemd's
machined service. The maximum number of threads per process is recorded
in the pids.max file under the machine's pids controller cgroup hierarchy,
e.g.
$cgrp-mnt/pids/machine.slice/machine-qemu\\x2d1\\x2dtest.scope/pids.max
Maximum threads per process is controlled with the TasksMax property of
the systemd scope for the machine. This patch adds an option to qemu.conf
which can be used to override the maximum number of threads allowed per
qemu process. If the value of option is greater than zero, it will be set
in the TasksMax property of the machine's scope after creating the machine.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
When we allow multiple instances of the driver for the same user
account, using a separate root directory, we need to ensure mutual
exclusion. Use a pidfile to guarantee this.
In privileged libvirtd this ends up locking
/var/run/libvirt/qemu/driver.pid
In unprivileged libvirtd this ends up locking
/run/user/$UID/libvirt/qemu/run/driver.pid
NB, the latter can vary depending on $XDG_RUNTIME_DIR
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In cases when e.g. a new feature breaks upstream behaviour it's useful
to allow users to disable the new feature to verify the regression and
possibly use it as a workaround until a fix is available.
The new qemu.conf option named "capability_filters" allows to remove
qemu capabilities from the detected bitmap.
This patch introduces the configuration infrastructure to parse the
option and pass it around.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
qemu_conf.c deals with the configuration file. Better fit for the
structure and freeing function will be qemu_domain.c where the rest of
the namespace parsing/formatting stuff resides.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The data injected via the namespace may contain also other things than
commandline passthrough definitions. Rename it to make it more
universal.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Unused as of:
commit f136b83139c63f20de0df3285d9e82df2fb97bfc
qemu: Rework setting process affinity
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
Add an option that lets the user specify the secret
that unlocks the server TLS key.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Introduce a set of bool variables with the 'present' suffix
to track whether the value was actually specified.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Require that all headers are guarded by a symbol named
LIBVIRT_$FILENAME
where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.
Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
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>
This reverts commit 8b8aefb3d6ae2139ea3d4ef6d7dd2c06f57f6075.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
For metadata locking we might need an extra fork() which given
latest attempts to do fewer fork()-s is suboptimal. Therefore,
there will be a qemu.conf knob to {en|dis}able this feature. But
since the feature is actually not metadata locking itself rather
than remembering of the original owner of the file this is named
as 'rememberOwner'. But patches for that feature are not even
posted yet so there is actually no qemu.conf entry in this patch
nor a way to enable this feature.
Even though this is effectively a dead code for now it is still
desired.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This config option allows users to set and enable lock manager
for domain metadata. The lock manager is going to be used by
security drivers to serialize each other when changing a file
ownership or changing the SELinux label. The only supported lock
manager is 'lockd' for now.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The option is insecure and it has been long enough for users to migrate
their disk files to use explicit format. Drop the option and related
code.
The config parser still parses it and rejects statup if it's still
present in the config in enabled state.
The augeas lens is also kept so that users can disable it.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Extend qemu_conf with user and group for running the tpm-emulator
and add directories to the configuration for the locations of the
log, state, and socket of the tpm-emulator.
Also add these new directories to the QEMU Makefile.inc.am and
the RPM spec file libvirt.spec.in.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just like we allow users overriding path to bridge-helper
detected at compile time we can allow them to override path to
qemu-pr-helper.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Host tcp4/tcp6 ports is a global resource thus we need to make
port accounting also global or we have issues described in [1] when
port allocator ranges of different instances are overlapped (which
is by default for qemu for example).
Let's have only one global port allocator object that take care
of the entire ports range (0 - 65535) and introduce port range object
for clients to specify desired auto allocation band.
[1] https://www.redhat.com/archives/libvir-list/2017-December/msg00600.html
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Rather than expecting callers to pass a virConnectPtr into the
virDomainDiskTranslateSourcePool() method, just acquire a connection
to the storage driver when needed.
Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This reverts commit 038eb472a0d970a17ccf4343ead0666df5c92f9d.
On reflection adding defaults for arbitrary guest XML device config
settings to the qemu.conf is not a sustainable path. Removing the
support for rx/tx queue size so that it doesn't set a bad precedent.
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
In 2074ef6cd4a2 and c56cdf259 (and friends) we've added two
attributes to virtio NICs: rx_queue_size and tx_queue_size.
However, sysadmins might want to set these on per-host basis but
don't necessarily have an access to domain XML (e.g. because they
are generated by some other app). So let's expose them under
qemu.conf (the settings from domain XML still take precedence as
they are more specific ones).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In some cases management application needs to allocate memory for
qemu upfront and then just let qemu use that. Since we don't want
to expose path for memory-backend-file anywhere in the domain
XML, we can generate predictable paths. In this case:
$memoryBackingDir/libvirt/qemu/$shortName/$alias
where $shortName is result of virDomainDefGetShortName().
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In near future we will need more than just a plain VIR_STRDUP().
Better implement that in a separate function and in
qemuBuildMemoryBackendStr() which is complicated enough already.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Add a new TLS X.509 certificate type - "vxhs". This will handle the
creation of a TLS certificate capability for properly configured
VxHS network block device clients.
The following describes the behavior of TLS for VxHS block device:
(1) Two new options have been added in /etc/libvirt/qemu.conf
to control TLS behavior with VxHS block devices
"vxhs_tls" and "vxhs_tls_x509_cert_dir".
(2) Setting "vxhs_tls=1" in /etc/libvirt/qemu.conf will enable
TLS for VxHS block devices.
(3) "vxhs_tls_x509_cert_dir" can be set to the full path where the
TLS CA certificate and the client certificate and keys are saved.
If this value is missing, the "default_tls_x509_cert_dir" will be
used instead. If the environment is not configured properly the
authentication to the VxHS server will fail.
Signed-off-by: Ashish Mittal <Ashish.Mittal@veritas.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1458630
Introduce virQEMUDriverConfigTLSDirResetDefaults in order to check
if the defaultTLSx509certdir was changed, then change the default
for any other *TLSx509certdir that was not set to the default default.
Introduce virQEMUDriverConfigValidate to validate the existence of
any of the *_tls_x509_cert_dir values that were uncommented/set,
incuding the default.
Update the qemu.conf description for default to describe the consequences
if the default directory path does not exist.
Signed-off-by: John Ferlan <jferlan@redhat.com>
The switch contains considerable amount of changes:
virQEMUCapsRememberCached() is removed because this is now handled
by virFileCacheSave().
virQEMUCapsInitCached() is removed because this is now handled by
virFileCacheLoad().
virQEMUCapsNewForBinary() is split into two functions,
virQEMUCapsNewData() which creates new data if there is nothing
cached and virQEMUCapsLoadFile() which loads the cached data.
This is now handled by virFileCacheNewData().
virQEMUCapsCacheValidate() is removed because this is now handled by
virFileCacheValidate().
virQEMUCapsCacheFree() is removed because it's no longer required.
Add virCapsPtr into virQEMUCapsCachePriv because for each call of
virFileCacheLookup*() we need to use current virCapsPtr.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Add a new TLS X.509 certificate type - "migrate". This will handle the
creation of a TLS certificate capability (and possibly repository) to
be used for migrations. Similar to chardev's, credentials will be handled
via a libvirt secrets; however, unlike chardev's enablement and usage
will be via a CLI flag instead of a conf flag and a domain XML attribute.
The migrations using the *x509_verify flag require the client-cert.pem
and client-key.pem files to be present in the TLS directory - so let's
also be sure to note that in the qemu.conf file.
Signed-off-by: John Ferlan <jferlan@redhat.com>
The bare fact that mnt namespace is available is not enough for
us to allow/enable qemu namespaces feature. There are other
requirements: we must copy all the ACL & SELinux labels otherwise
we might grant access that is administratively forbidden or vice
versa.
At the same time, the check for namespace prerequisites is moved
from domain startup time to qemu.conf parser as it doesn't make
much sense to allow users to start misconfigured libvirt just to
find out they can't start a single domain.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Add new parameter memory_backing_dir where files will be stored when memoryBacking
source is selected as file.
Value is stored inside char* memoryBackingDir
Given how intrusive previous patches are, it might happen that
there's a bug or imperfection. Lets give users a way out: if they
set 'namespaces' to an empty array in qemu.conf the feature is
suppressed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
If you've ever tried running a huge page backed guest under
different user than in qemu.conf, you probably failed. Problem is
even though we have corresponding APIs in the security drivers,
there's no implementation and thus we don't relabel the huge page
path. But even if we did, so far all of the domains share the
same path:
/hugepageMount/libvirt/qemu
Our only option there would be to set 0777 mode on the qemu dir
which is totally unsafe. Therefore, we can create dir on
per-domain basis, i.e.:
/hugepageMount/libvirt/qemu/domainName
and chown domainName dir to the user that domain is configured to
run under.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This helps in selecting log level of the gluster gfapi, output to stderr.
The option is 'gluster_debug_level', can be tuned by editing
'/etc/libvirt/qemu.conf'
Debug levels ranges 0-9, with 9 being the most verbose, and 0
representing no debugging output. The default is the same as it was
before, which is a level of 4. The current logging levels defined in
the gluster gfapi are:
0 - None
1 - Emergency
2 - Alert
3 - Critical
4 - Error
5 - Warning
6 - Notice
7 - Info
8 - Debug
9 - Trace
Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Add a new qemu.conf variables to store the UUID for the secret that could
be used to present credentials to access the TLS chardev. Since this will
be a server level and it's possible to use some sort of default, introduce
both the default and chardev logic at the same time making the setting of
the chardev check for it's own value, then if not present checking whether
the default value had been set.
Signed-off-by: John Ferlan <jferlan@redhat.com>
