Remove all usage of ATTRIBUTE_NORETURN in favor of GLib's
G_GNUC_NORETURN.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

Add an exception for the GLib versions of the macros we already ignore.
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

They are already defined in glib.h.

(libxml2 also has them defined)
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>

In order to have multiple security drivers hidden under one
virSecurity* call, we have virSecurityStack driver which holds a
list of registered security drivers and for every virSecurity*
call it iterates over the list and calls corresponding callback
in real security drivers. For instance, for
virSecurityManagerSetAllLabel() it calls
domainSetSecurityAllLabel callback sequentially in NOP, DAC and
(possibly) SELinux or AppArmor drivers. This works just fine if
the callback from every driver returns success. Problem arises
when one of the drivers fails. For instance, aforementioned
SetAllLabel() succeeds for DAC but fails in SELinux in which
case all files that DAC relabelled are now owned by qemu:qemu (or
whomever runs qemu) and thus permissions are leaked. This is even
more visible with XATTRs which remain set for DAC.

The solution is to perform a rollback on failure, i.e. call
opposite action on drivers that succeeded.

I'm providing rollback only for set calls and intentionally
omitting restore calls for two reasons:

1) restore calls are less likely to fail (they merely remove
XATTRs and chown()/setfilecon() file - all of these operations
succeeded in set call),

2) we are not really interested in restore failures - in a very
few places we check for retval of a restore function we do so
only to print a warning.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1740024Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

In near future we will need to walk through the list of internal
drivers in reversed order. The simplest solution is to turn
singly linked list into a doubly linked list.
We will not need to start from the end really, so there's no tail
pointer kept.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

This function returns the name of the secdriver. Since the name
is invariant we don't really need to lock the manager - it won't
change.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

This function is in fact returning the name of the virtualization
driver that registered the security manager/driver.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

In upcoming commits, virSecurityManagerSetAllLabel() will perform
rollback in case of failure by calling
virSecurityManagerRestoreAllLabel(). But in order to do that, the
former needs to have @migrated argument so that it can be passed
to the latter.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

The usleep function was missing on older mingw versions, but we can rely
on it existing everywhere these days. It may only support times upto 1
second in duration though, so we'll prefer to use g_usleep instead.

The commandhelper program is not changed since that can't link to glib.
Fortunately it doesn't need to build on Windows platforms either.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

g_strerror is offers the safety/correctness benefits of strerror_r, with
the API design convenience of strerror.

Use of virStrerror should be eliminated through the codebase in favour
of g_strerror.

commandhelper.c is a special case as its a tiny single threaded test
program, not linked to glib, so it just uses traditional strerror().
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Converting from virObject to GObject is reasonably straightforward,
as illustrated by this patch for virIdentity

In the header file

 - Remove

     typedef struct _virIdentity virIdentity

 - Add

     #define VIR_TYPE_IDENTITY virIdentity_get_type ()
     G_DECLARE_FINAL_TYPE (virIdentity, vir_identity, VIR, IDENTITY, GObject);

   Which provides the typedef we just removed, and class
   declaration boilerplate and various other constants/macros.

In the source file

 - Change 'virObject parent' to 'GObject parent' in the struct
 - Remove the virClass variable and its initializing call
 - Add

      G_DEFINE_TYPE(virIdentity, vir_identity, G_TYPE_OBJECT)

   which declares the instance & class constructor functions

 - Add an impl of the instance & class constructors
   wiring up the finalize method to point to our dispose impl

In all files

 - Replace VIR_AUTOUNREF(virIdentityPtr) with g_autoptr(virIdentity)

 - Replace virObjectRef/Unref with g_object_ref/unref. Note
   the latter functions do *NOT* accept a NULL object where as
   libvirt's do. If you replace g_object_unref with g_clear_object
   it is NULL safe, but also clears the pointer.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

To simplify the later conversion from virObject to GObject, introduce
the use of g_autoptr to the virIdentity implementnation and test suite.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Replace use of the gnulib base64 module with glib's own base64 API family.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel 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: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

To facilitate porting over to glib, this rewrites the auto cleanup
macros to use glib's equivalent.

As a result it is now possible to use g_autoptr/VIR_AUTOPTR, and
g_auto/VIR_AUTOCLEAN, g_autofree/VIR_AUTOFREE interchangably, regardless
of which macros were used to declare the cleanup types.

Within the scope of any single method, code must remain consistent
using either GLib or Libvirt macros, never mixing both. New code
must preferentially use the GLib macros, and old code will be
converted incrementally.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Using the standard macro will facilitate the conversion to glib's
auto cleanup macros.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Convert the string duplication APIs to use the g_strdup family of APIs.

We previously used the 'strdup-posix' gnulib module because mingw does
not set errno to ENOMEM on failure

We previously used the 'strndup' gnulib module because this function
does not exist on mingw.

We previously used the 'vasprintf' gnulib module because of many GNU
supported format specifiers not working on non-Linux platforms. glib's
own equivalent standardizes on GNU format specifiers too.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Convert the VIR_ALLOC family of APIs with use of the g_malloc family of
APIs. Use of VIR_ALLOC related functions should be incrementally phased
out over time, allowing return value checks to be dropped. Use of
VIR_FREE should be replaced with auto-cleanup whenever possible.

We previously used the 'calloc-posix' gnulib module because mingw does
not set errno to ENOMEM on failure.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Add the main glib.h to internal.h so that all common code can use it.

Historically glib allowed applications to register an alternative
memory allocator, so mixing g_malloc/g_free with malloc/free was not
safe.

This was feature was dropped in 2.46.0 with:

      commit 3be6ed60aa58095691bd697344765e715a327fc1
      Author: Alexander Larsson <alexl@redhat.com>
      Date:   Sat Jun 27 18:38:42 2015 +0200

        Deprecate and drop support for memory vtables

Applications are still encourged to match g_malloc/g_free, but it is no
longer a mandatory requirement for correctness, just stylistic. This is
explicitly clarified in

    commit 1f24b36607bf708f037396014b2cdbc08d67b275
    Author: Daniel P. Berrangé <berrange@redhat.com>
    Date:   Thu Sep 5 14:37:54 2019 +0100

        gmem: clarify that g_malloc always uses the system allocator

Applications can still use custom allocators in general, but they must
do this by linking to a library that replaces the core malloc/free
implemenentation entirely, instead of via a glib specific call.

This means that libvirt does not need to be concerned about use of
g_malloc/g_free causing an ABI change in the public libary, and can
avoid memory copying when talking to external libraries.

This patch probes for glib, which provides the foundation layer with
a collection of data structures, helper APIs, and platform portability
logic.

Later patches will introduce linkage to gobject which provides the
object type system, built on glib, and gio which providing objects
for various interesting tasks, most notably including DBus client
and server support and portable sockets APIs, but much more too.
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Prepare for linking with glib by probing for it at configure
time. Per supported platforms target, the min glib versions on
relevant distros are:

  RHEL-8: 2.56.1
  RHEL-7: 2.50.3
  Debian (Buster): 2.58.3
  Debian (Stretch): 2.50.3
  OpenBSD (Ports): 2.58.3
  FreeBSD (Ports): 2.56.3
  OpenSUSE Leap 15: 2.54.3
  SLE12-SP2: 2.48.2
  Ubuntu (Xenial): 2.48.0
  macOS (Homebrew): 2.56.0

This suggests that a minimum glib of 2.48 is a reasonable target.
This aligns with the minimum version required by qemu too.

We must disable the bad-function-cast warning as various GLib APIs
and macros will trigger this.
Reviewed-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

We mirror the labeling strategy that was used for its top image
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

This will be used for recursing into externalDataStore
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

Rename the existing virSecuritySELinuxRestoreImageLabelInt
to virSecuritySELinuxRestoreImageLabelSingle, and extend the new
ImageLabelInt handle externalDataStore
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

This will simplify future patches and make the logic easier to follow
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

The only caller always passes in a non-null parent
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

All the SetFileCon calls only differ by the label they pass in.
Rework the conditionals to track what label we need, and use a
single SetFileCon call
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

We mirror the labeling strategy that was used for its sibling
image
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

This will be used for recursing into externalDataStore
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

Rename the existing virSecurityDACRestoreImageLabelInt
to virSecurityDACRestoreImageLabelSingle, and extend the new
ImageLabelInt handle externalDataStore
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

This will simplify future patches and make the logic easier to follow
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

The only caller always passes in a non-null parent
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

Add virStorageSourceNewFromExternalData, similar to
virStorageSourceNewFromBacking and use it to fill in a
virStorageSource for externalDataStore
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>

Add the plumbing to track a externalDataStoreRaw as a virStorageSource
Reviewed-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichal Privoznik <mprivozn@redhat.com>
Signed-off-by: NCole Robinson <crobinso@redhat.com>