A secret can be marked with the "private" attribute. The intent was that
it is not possible for any libvirt client to be able to read the secret
value, it would only be accesible from within libvirtd. eg the QEMU
driver can read the value to launch a guest.
With the modular daemons, the QEMU, storage and secret drivers are all
running in separate daemons. The QEMU and storage drivers thus appear to
be normal libvirt client's from the POV of the secret driver, and thus
they are not able to read a private secret. This is unhelpful.
With the previous patches that introduced a "system token" to the
identity object, we can now distinguish APIs invoked by libvirt daemons
from those invoked by client applications.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When fetching the value of a private secret, we need to use an elevated
identity otherwise the secret driver will deny access.
When using the modular daemons, the elevated identity needs to be active
before the secret driver connection is opened, and it will apply to all
APIs calls made on that conncetion.
When using the monolithic daemon, the identity at time of opening the
connection is ignored, and the elevated identity needs to be active
precisely at the time the virSecretGetValue API call is made.
After acquiring the secret value, the elevated identity should be
cleared.
This sounds complex, but is fairly straightfoward with the automatic
cleanup callbacks.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The drivers can all call virGetConnectXXX to open a connection to a
secondary driver. For example, when creating a encrypted storage volume,
the storage driver has to open a secret driver connection, or when
starting a guest, the QEMU driver has to open the network driver to
lookup a virtual network.
When using monolithic libvirtd, the connection has the same effective
identity as the client, since everything is still in the same process.
When using the modular daemons, however, the remote daemon sees the
identity of the calling daemon. This is a mistake as it results in
the modular daemons seeing the client with elevated privileges.
We need to pass on the current identity explicitly when opening the
secondary drivers. This is the same thing that is done by daemon RPC
dispatcher code when it is directly forwarding top level API calls
from virtproxyd and other daemons.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This is essentially a way to determine if the current identity
is that of another libvirt daemon.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When talking to the secret driver, the callers inside libvirt daemons
need to be able to run with an elevated privileges that prove the API
calls are made by a libvirt daemon, not an end user application.
The virIdentityElevateCurrent method will take the current identity
and, if not already present, add the system token. The old current
identity is returned to the caller. With the VIR_IDENTITY_AUTORESTORE
annotation, the old current identity will be restored upon leaving
the codeblock scope.
... early work with regular privileges ...
if (something needing elevated privs) {
VIR_IDENTITY_AUTORESTORE virIdentity *oldident =
virIdentityElevateCurrent();
if (!oldident)
return -1;
... do something with elevated privileges ...
}
... later work with regular privileges ...
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
When creating the system identity set the system token. The system
token is currently stored in a local path
/var/run/libvirt/common/system.token
Obviously with only traditional UNIX DAC in effect, this is largely
security through obscurity, if the client is running at the same
privilege level as the daemon. It does, however, reliably distinguish
an unprivileged client from the system daemons.
With a MAC system like SELinux though, or possible use of containers,
access can be further restricted.
A possible future improvement for Linux would be to populate the
kernel keyring with a secret for libvirt daemons to share.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
We want a way to distinguish between calls from a libvirt daemon, and a
regular client application when both are running as the same user
account. This is not possible with the current set of attributes
recorded against an identity, as there is nothing that is common to all
of the modular libvirt daemons, while distinct to all other processes.
We thus introduce the idea of a system token, which is simply a random
hex string that is only known by the libvirt daemons, to be recorded
against the system identity.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
A random token is simply a string of random bytes formatted in
hexidecimal.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The libvirt-daemon package now provides the 'libvirt-admin' virtual
name, but the Provides stanza doesn't declare version information,
which breaks things depending on that package using a versioned
dependency. Fix this by setting the version-release of libvirt to
that name to mimic the previous state.
Fixes: 2244ac168d
Signed-off-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
In the distros using RPMs, we build libvirt once as a side effect
of running "ninja dist", and once via rpmbuild.
In addition "ninja dist" will run all tests including the "syntax-check"
suite, despite use having a separate "codestyle" job for for that.
There is no way to pass "--no-suite" when creating the dist, but if we
switch to invoking "meson dist", we can skip the build+test part
entirely using "--no-tests".
When doing this we then run explicit "meson compile" and "meson test"
commands for the distros that don't build the RPMs, and in the latter
case we can now skip the "syntax-check" suite.
The RPM builds already skipped the "syntax-check" suite.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The "dist" and "test" targets in ninja end up calling back into
the equivalent meson commands. The meson commands support various
arguments that are not accessible when invoked via ninja, so it
is preferrable to use meson directly.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
The "DIST=skip" flag as used in CentOS 7 jobs to workaround a problem
with older git versions. This is no longer required since
commit d35003aee7
Author: Andrea Bolognani <abologna@redhat.com>
Date: Tue May 4 10:45:29 2021 +0200
ci: Drop CentOS 7
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
"meson test" will only print a list of which tests fail by default,
so we were sending the full test log to stdout on failure. This makes
it really hard to see the errors though as the test log has all
succcesful tests too.
"ninja test" will print the same as "meson test", following by details
of each failure.
It does this using the "--print-errorlog" flag, so lets use that in
the codestyle job.
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
This is automatically picked up by the dependency generator, so
there's no reason to have this here.
Signed-off-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
No need to check whether we're on Fedora, because checking
whether the version of Fedora is recent enough implictly does
that already.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
It's only used in one place, and it's nicer to keep the error
message close to the check that causes it to be emitted.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
The rewritten checks, which made it possible to drop the
variable, are in fact not equivalent to the original ones,
and rewriting them once again so that they are would make
them unwieldy. Let's go back to how things were.
Reverts: 69c8d5954e
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
The width of `unsigned long` differs on 32 bit and 64 bit architectures.
There is no compelling reason why the maximum DHCP lease time should
depend on the architecture.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
This is a rewrite of:
https://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit
Once this commit merges, the above wiki should point to this kbase
document.
NB: I've intentionally left out the example for pull-based full backups.
I'll tackle it once QMP `x-blockdev-reopen` comes out of experimental
mode in upstream QEMU. Then pull-based can be described for both full
and and differntial backups.
Overall, future documents should cover:
- full backups using both push- and pull-mode
- differential backups using both push- and pull-mode
Signed-off-by: Kashyap Chamarthy <kchamart@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
When QEMU introduces new firmware features libvirt will fail until we
list that feature in our code as well which doesn't sound right.
We should simply ignore the new feature until we add a proper support
for it.
Reported-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Some variables are needed only inside for() loop. They were
declared at the beginning of the function because of VIR_FREE()
calls, but since they are auto-freed they can be declared inside
the loop.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
What this function really does it takes ownership of all pointers
passed (well, except for the first one - caps - to which it
registers new NUMA node). But since all info is passed as a
single pointer it's hard to tell (and use g_auto*). Let's use
double pointers to make the ownership transfer obvious.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The @cpus variable is an array of structs in which each item
contains a virBitmap member. As such it is not enough to just
VIR_FREE() the array - each bitmap has to be freed too.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The rest of virCapabilities format functions take virBuffer as
the first argument and struct to format as the second. Also, they
accept NULL (as the second argument). Fix
virCapabilitiesHostNUMAFormat() so that it follows this logic.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The securityselinuxhelper is a mock that's replacing libselinux
APIs with our own implementation to achieve deterministic
results. Our implementation uses env vars (among other things) to
hold internal state. For instance, "FAKE_SELINUX_CONTEXT" and
"FAKE_SELINUX_DISABLED" variables are used. However, as we were
switching from setenv() to g_setenv() we also changed the set of
possible retvals from setcon_raw() and security_disable().
Previously, the retval of setenv() was used directly which
returns 0 on success and -1 on error. But g_setenv() has
different retval semantics: it returns 1 on success and 0 on
error.
This discrepancy can be observed by running viridentitytest where
case #2 reports an error ("!") - because setcon_raw() returns 1.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Linux 5.13 introduces "kcpuid", a tool similar to "cpuid", see
https://lore.kernel.org/lkml/1614928878-86075-1-git-send-email-feng.tang@intel.com/
Output formats of cpuid and kcpuid differ slightly. This adds support
for the latter.
Signed-off-by: Tim Wiederhake <twiederh@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Since its introduction in v0.9.1~65 the virOnce() was expected to
follow the usual retval logic (0 for success, a negative number
for failure). However, that was never the case.
On the other hand, looking into glibc and musl the pthread_once()
never returns anything other than zero (uclibc-ng seems to not
implement pthread_once()), therefore we never really hit any
problem. But for code cleanliness (and to match POSIX
documentation), let's change to code so that our retval logic is
honoured.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Compilers aren't able to see whether @result is set or not and thus
don't warn of a potential use of uninitialized value. Always set @result
to prevent uninitialized use.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
There are few cases where we set a default value when using
virXMLPropEnum which can be converted to virXMLPropEnumDefault.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>