Completely rework how settings plugin handle connections and how
NMSettings tracks the list of connections.
Previously, settings plugins would return objects of (a subtype of) type
NMSettingsConnection. The NMSettingsConnection was tightly coupled with
the settings plugin. That has a lot of downsides.
Change that. When changing this basic relation how settings connections
are tracked, everything falls appart. That's why this is a huge change.
Also, since I have to largely rewrite the settings plugins, I also
added support for multiple keyfile directories, handle in-memory
connections only by keyfile plugin and (partly) use copy-on-write NMConnection
instances. I don't want to spend effort rewriting large parts while
preserving the old way, that anyway should change. E.g. while rewriting ifcfg-rh,
I don't want to let it handle in-memory connections because that's not right
long-term.
--
If the settings plugins themself create subtypes of NMSettingsConnection
instances, then a lot of knowledge about tracking connections moves
to the plugins.
Just try to follow the code what happend during nm_settings_add_connection().
Note how the logic is spread out:
- nm_settings_add_connection() calls plugin's add_connection()
- add_connection() creates a NMSettingsConnection subtype
- the plugin has to know that it's called during add-connection and
not emit NM_SETTINGS_PLUGIN_CONNECTION_ADDED signal
- NMSettings calls claim_connection() which hocks up the new
NMSettingsConnection instance and configures the instance
(like calling nm_settings_connection_added()).
This summary does not sound like a lot, but try to follow that code. The logic
is all over the place.
Instead, settings plugins should have a very simple API for adding, modifying,
deleting, loading and reloading connections. All the plugin does is to return a
NMSettingsStorage handle. The storage instance is a handle to identify a profile
in storage (e.g. a particular file). The settings plugin is free to subtype
NMSettingsStorage, but it's not necessary.
There are no more events raised, and the settings plugin implements the small
API in a straightforward manner.
NMSettings now drives all of this. Even NMSettingsConnection has now
very little concern about how it's tracked and delegates only to NMSettings.
This should make settings plugins simpler. Currently settings plugins
are so cumbersome to implement, that we avoid having them. It should not be
like that and it should be easy, beneficial and lightweight to create a new
settings plugin.
Note also how the settings plugins no longer care about duplicate UUIDs.
Duplicated UUIDs are a fact of life and NMSettings must handle them. No
need to overly concern settings plugins with that.
--
NMSettingsConnection is exposed directly on D-Bus (being a subtype of
NMDBusObject) but it was also a GObject type provided by the settings
plugin. Hence, it was not possible to migrate a profile from one plugin to
another.
However that would be useful when one profile does not support a
connection type (like ifcfg-rh not supporting VPN). Currently such
migration is not implemented except for migrating them to/from keyfile's
run directory. The problem is that migrating profiles in general is
complicated but in some cases it is important to do.
For example checkpoint rollback should recreate the profile in the right
settings plugin, not just add it to persistent storage. This is not yet
properly implemented.
--
Previously, both keyfile and ifcfg-rh plugin implemented in-memory (unsaved)
profiles, while ifupdown plugin cannot handle them. That meant duplication of code
and a ifupdown profile could not be modified or made unsaved.
This is now unified and only keyfile plugin handles in-memory profiles (bgo #744711).
Also, NMSettings is aware of such profiles and treats them specially.
In particular, NMSettings drives the migration between persistent and non-persistent
storage.
Note that a settings plugins may create truly generated, in-memory profiles.
The settings plugin is free to generate and persist the profiles in any way it
wishes. But the concept of "unsaved" profiles is now something explicitly handled
by keyfile plugin. Also, these "unsaved" keyfile profiles are persisted to file system
too, to the /run directory. This is great for two reasons: first of all, all
profiles from keyfile storage in fact have a backing file -- even the
unsaved ones. It also means you can create "unsaved" profiles in /run
and load them with `nmcli connection load`, meaning there is a file
based API for creating unsaved profiles.
The other advantage is that these profiles now survive restarting
NetworkManager. It's paramount that restarting the daemon is as
non-disruptive as possible. Persisting unsaved files to /run improves
here significantly.
--
In the past, NMSettingsConnection also implemented NMConnection interface.
That was already changed a while ago and instead users call now
nm_settings_connection_get_connection() to delegate to a
NMSimpleConnection. What however still happened was that the NMConnection
instance gets never swapped but instead the instance was modified with
nm_connection_replace_settings_from_connection(), clear-secrets, etc.
Change that and treat the NMConnection instance immutable. Instead of modifying
it, reference/clone a new instance. This changes that previously when somebody
wanted to keep a reference to an NMConnection, then the profile would be cloned.
Now, it is supposed to be safe to reference the instance directly and everybody
must ensure not to modify the instance. nmtst_connection_assert_unchanging()
should help with that.
The point is that the settings plugins may keep references to the
NMConnection instance, and so does the NMSettingsConnection. We want
to avoid cloning the instances as long as they are the same.
Likewise, the device's applied connection can now also be referenced
instead of cloning it. This is not yet done, and possibly there are
further improvements possible.
--
Also implement multiple keyfile directores /usr/lib, /etc, /run (rh #1674545,
bgo #772414).
It was always the case that multiple files could provide the same UUID
(both in case of keyfile and ifcfg-rh). For keyfile plugin, if a profile in
read-only storage in /usr/lib gets modified, then it gets actually stored in
/etc (or /run, if the profile is unsaved).
--
While at it, make /etc/network/interfaces profiles for ifupdown plugin reloadable.
--
https://bugzilla.gnome.org/show_bug.cgi?id=772414https://bugzilla.gnome.org/show_bug.cgi?id=744711https://bugzilla.redhat.com/show_bug.cgi?id=1674545
We no longer add these. If you use Emacs, configure it yourself.
Also, due to our "smart-tab" usage the editor anyway does a subpar
job handling our tabs. However, on the upside every user can choose
whatever tab-width he/she prefers. If "smart-tabs" are used properly
(like we do), every tab-width will work.
No manual changes, just ran commands:
F=($(git grep -l -e '-\*-'))
sed '1 { /\/\* *-\*- *[mM]ode.*\*\/$/d }' -i "${F[@]}"
sed '1,4 { /^\(#\|--\|dnl\) *-\*- [mM]ode/d }' -i "${F[@]}"
Check remaining lines with:
git grep -e '-\*-'
The ultimate purpose of this is to cleanup our files and eventually use
SPDX license identifiers. For that, first get rid of the boilerplate lines.
WireGuard devices are (will be) regular NMDevice implementations,
but NMDnsManager should treat them like VPN.
For that, reuse the device's type and nm_device_get_route_metric_default().
NM_UTILS_LOOKUP_STR() uses alloca(). Partly to avoid the overhead of
malloc(), but more important because it's convenient to use. It does
not require to declare a varible to manage the lifetime of the heap
allocation.
It's quite safe, because the stack allocation is of a fixed size of only
a few bytes. Overall, I think the convenience that we get (resulting in
simpler code) outweighs the danger of stack allocation in this case. It's
still worth it.
However, as it uses alloca(), it still must not be used inside a (unbound)
loop and it is obviously a macro.
Rename the macros to have a _A() suffix. This should make the
peculiarities more apparent.
While nm_utils_inet*_ntop() accepts a %NULL buffer to fallback
to a static buffer, don't do that.
I find the possibility of using a static buffer here error prone
and something that should be avoided. There is of course the downside,
that in some cases it requires an additional line of code to allocate
the buffer on the stack as auto-variable.
The reasons to block autoconnection at settings level are not the same
as the ones to block autoconnection at device level.
E.g. if the SIM-PIN is wrong, you may want to block autoconnection
both at settings level (as the PIN configured in settings is wrong)
and at device level (so that no other setting is tried automatically).
For some other reasons, you may want to block autoconnection only at
setting level (e.g. wrong APN).
And for some other reasons you may want to block autoconnection at
device level only (e.g. SIM missing), so that the autoconnection
blocking is removed when the device goes away. This is especially
important with SIM hotplug events processed by ModemManager, as a
device without SIM will be removed from MM when a new SIM is
inserted, so that a completely new object is exposed in MM with the
newly detected SIM.
https://github.com/NetworkManager/NetworkManager/pull/259
By setting "connection.permissions", a profile is restricted to a
particular user.
That means for example, that another user cannot see, modify, delete,
activate or deactivate the profile. It also means, that the profile
will only autoconnect when the user is logged in (has a session).
Note that root is always able to activate the profile. Likewise, the
user is also allowed to manually activate the own profile, even if no
session currently exists (which can easily happen with `sudo`).
When the user logs out (the session goes away), we want do disconnect
the profile, however there are conflicting goals here:
1) if the profile was activate by root user, then logging out the user
should not disconnect the profile. The patch fixes that by not
binding the activation to the connection, if the activation is done
by the root user.
2) if the profile was activated by the owner when it had no session,
then it should stay alive until the user logs in (once) and logs
out again. This is already handled by the previous commit.
Yes, this point is odd. If you first do
$ sudo -u $OTHER_USER nmcli connection up $PROFILE
the profile activates despite not having a session. If you then
$ ssh guest@localhost nmcli device
you'll still see the profile active. However, the moment the SSH session
ends, a session closes and the profile disconnects. It's unclear, how to
solve that any better. I think, a user who cares about this, should not
activate the profile without having a session in the first place.
There are quite some special cases, in particular with internal
activations. In those cases we need to decide whether to bind the
activation to the profile's visibility.
Also, expose the "bind" setting in the D-Bus API. Note, that in the future
this flag may be modified via D-Bus API. Like we may also add related API
that allows to tweak the lifetime of the activation.
Also, I think we broke handling of connection visiblity with 37e8c53eee
"core: Introduce helper class to track connection keep alive". This
should be fixed now too, with improved behavior.
Fixes: 37e8c53eeehttps://bugzilla.redhat.com/show_bug.cgi?id=1530977
Now that the keep-alive instance defaults to ALIVE by default, we can
always arm it when starting to activate the active-connection.
The keep-alive instance may have been armed earlier already:
for example, when binding its lifetime to a D-Bus name or
when watching the connection's visible state.
However, at the moment when we queue the active-connection for
activation, we also want to make sure that the keep-alive instance is
armed. It is nicer for consistancy reasons.
Note, that nm_keep_alive_arm() has no effect if nm_keep_alive_disarm()
was called earlier already. Also note, that NMActiveConnection will
disarm the keep-alive instance, when changing to a state greater than
ACTIVATED. So, all works together nicely.
Also, no longer arm the keep-alive instance in the constructor of
NMActiveConnection. It would essentially mean, that the instances
is aremd very early.
Also, as alternative point of interest, arm the keep-alive instance
when registering the signal handler in "nm-policy.c".
It's not clear that calling nm_manager_deactivate_connection() does not
remove the active-connection entirely from the list. Just to be sure, use
nm_manager_for_each_active_connection_safe() which allows deleting the
current entry while iterating (all other modifications to the list are not
allowed).
NMKeepAlive is a proper GObject type, with a specific API that on the one
end allows to configure watches/bindings, and on the other end exposes
and is-alive property and the owner instance. That's great, as NMActiveConnection
is not concerned with either end (moving complexity away from
"nm-active-connection.c") and as we later can reuse NMKeepAlive with
NMSettingsConnection.
However, we don't need to wrap this API by NMActiveConnection. Doing so
means, we need to expose all the watch/bind functions also as part of
NMActiveConnection API.
The only ugliness here is, that NMPolicy subscribes to property changed
signal of the keep alive instance, which would fail horribly if
NMActiveConnection ever decides to swap the keep alive instance (in
which case NMPolicy would have to disconnect the signal, and possibly
reconnect it to another NMKeepAlive instance). We avoid that by just not
doing that and documenting it.
Most (not all) functions that can fail and report the reason with
an GError are required to set the error if they fail. It's a bug
to claim to fail without returning the GError reason.
Hence, our callers usually don't check whether a GError is present but
just access it.
Likewise, for better or worse, our GError codes are often not meaningful
(unless explicitly documented). Meaning, logging the error code number
is not helpful. Instead, error messages should be written in a manner
that one can find the source code location where it happened.
Also, return-early to reduce the indentation level of the code.
Also, drop the code comment. It seems to just describe what is obviously
visible by reading the source. It doesn't explain much beside that the
"doesn't have a reason", but not really why.
For P2P connections it makes sense to bind the connection to the status
of the operation that is being done. One example is that a wifi display
(miracast) P2P connection should be shut down when streaming fails for
some reason.
This new helper class allows binding a connection to the presence of a
DBus path meaning that it will be torn down if the process disappears.
NMConnection is an interface, which is implemented by the types
NMSimpleConnection (libnm-core), NMSettingsConnection (src) and
NMRemoteConnection (libnm).
NMSettingsConnection does a lot of things already:
1) it "is-a" NMDBusObject and exports the API of a connection profile
on D-Bus
2) it interacts with NMSettings and contains functionality
for tracking the profiles.
3) it is the base-class of types like NMSKeyfileConnection and
NMIfcfgConnection. These handle how the profile is persisted
on disk.
4) it implements NMConnection interface, to itself track the
settings of the profile.
3) and 4) would be better implemented via delegation than inheritance.
Address 4) and don't let NMSettingsConnection implemente the NMConnection
interface. Instead, a settings-connection references now a NMSimpleConnection
instance, to which it delegates for keeping the actual profiles.
Advantages:
- by delegating, there is a clearer separation of what
NMSettingsConnection does. For example, in C we often required
casts from NMSettingsConnection to NMConnection. NMConnection
is a very trivial object with very little logic. When we have
a NMConnection instance at hand, it's good to know that it is
*only* that simple instead of also being an entire
NMSettingsConnection instance.
The main purpose of this patch is to simplify the code by separating
the NMConnection from the NMSettingsConnection. We should generally
be aware whether we handle a NMSettingsConnection or a trivial
NMConnection instance. Now, because NMSettingsConnection no longer
"is-a" NMConnection, this distinction is apparent.
- NMConnection is implemented as an interface and we create
NMSimpleConnection instances whenever we need a real instance.
In GLib, interfaces have a performance overhead, that we needlessly
pay all the time. With this change, we no longer require
NMConnection to be an interface. Thus, in the future we could compile
a version of libnm-core for the daemon, where NMConnection is not an
interface but a GObject implementation akin to NMSimpleConnection.
- In the previous implementation, we cannot treat NMConnection immutable
and copy-on-write.
For example, when NMDevice needs a snapshot of the activated
profile as applied-connection, all it can do is clone the entire
NMSettingsConnection as a NMSimpleConnection.
Likewise, when we get a NMConnection instance and want to keep
a reference to it, we cannot do that, because we never know
who also references and modifies the instance.
By separating NMSettingsConnection we could in the future have
NMConnection immutable and copy-on-write, to avoid all unnecessary
clones.
In general, a activatable connection is one that is currently not
active, or supports to be activatable multiple times according to
multi-connect setting. In addition, during autoconnect, a profile
which is marked as multi-connect=manual-multiple will not be avalable.
Hence, add an argument "for_auto_activation".
The code is mostly unused but will be used next (except for connections,
which set connection.multi-connect=multiple).
Note the special error codes NM_UTILS_ERROR_CONNECTION_AVAILABLE_*.
This will be used to determine, whether the profile is fundamentally
incompatible with the device, or whether just some other properties
mismatch. That information will be importand during a plain `nmcli
connection up`, where NetworkManager searches all devices for a device
to activate. If no device is found (and multiple errors happened),
we want to show the error that is most likely relevant for the user.
Also note, how NMDevice's check_connection_compatible() uses the new
class field "device_class->connection_type_check_compatible" to simplify
checks for compatible profiles.
The error reason is still unused.
If a VPN with default route is activated, the Manager's
PrimaryConnection property is not updated to indicate the VPN as
primary connection.
This happens because the PrimaryConnection property gets updated when
the default_ipX_device property of NMPolicy changes, and the primary
connection is set to the activation request currently pending on the
default device. We select the base (for example, ethernet) device as
best device and therefore the NMActRequest active on it is selected as
primary connection.
This patch fixes the problem by properly selecting the VPN as
primary. It seems a better choice to track best active connections
directly from NMPolicy instead of going through two steps.
If the active connection is deactivated because the device is gone,
don't block autoconnection. Otherwise, whenever the device comes
back (e.g. maybe it was reset in the middle of a connection attempt),
the autoconnection logic won't be triggered, as the settings are still
blocked.
I'm able to reproduce this by performing a WWAN modem reset in the
middle of a connection attempt.
https://github.com/NetworkManager/NetworkManager/pull/121
Coccinelle:
@@
expression a, b;
@@
-a ? a : b
+a ?: b
Applied with:
spatch --sp-file ternary.cocci --in-place --smpl-spacing --dir .
With some manual adjustments on spots that Cocci didn't catch for
reasons unknown.
Thanks to the marvelous effort of the GNU compiler developer we can now
spare a couple of bits that could be used for more important things,
like this commit message. Standards commitees yet have to catch up.
"NMSettingsConnectionFlags" was an internal enum. Soon, we will add such
a type in libnm. Avoid the naming conflict by renaming. The "Int" stands
for "internal".
Specify a reason when creating active connections. The reason will be
used in the next commit to tell whether slaves must be reconnected or
not if a master has autoconnect-slaves=yes.
I find it slightly nicer and explict. Also, the list elements
are strictly speaking private, we should better not explicitly
use them outside of NMManager/NMDevice. The macro hides this.
Instead of using a GSList for tracking the devices, use a CList.
I think a CList is in most cases the more suitable data structure
then GSList:
- you can find out in O(1) whether the object is linked. That
is nice, for example to assert in NMDevice's destructor that
the object was unlinked, and we will use that later in
nm_manager_get_device_by_path().
- you can unlink the element in O(1) and you can unlink the
element without having access to the link's head
- Contrary to GSList, this does not require an extra slice
allocation for the link node. It quite possibliy consumes
slightly less memory because the CList structure is embedded
in a struct that we already allocate. Even if slice allocation
would be perfect to only consume 2*sizeof(gpointer) for the link
note, it would at most be as-good as CList. Quite possibly,
there is an overhead though.
- CList possibly has better memory locality, because the link
structure and the data are close to each other.
Something which could be seen as disavantage, is that with CList
one device can only be tracked in one NMManager instance at a time.
But that is fine. There exists only one NMManager instance for now,
and even if we would ever introduce multiple managers, we probably
would not associate one NMDevice instance with multiple managers.
The advantages are arguably not huge, but CList is IMHO clearly the
more suited data structure. No need to stick to a suboptimal data
structure for the job. Refactor it.
Previously, we used the generated GDBusInterfaceSkeleton types and glued
them via the NMExportedObject base class to our NM types. We also used
GDBusObjectManagerServer.
Don't do that anymore. The resulting code was more complicated despite (or
because?) using generated classes. It was hard to understand, complex, had
ordering-issues, and had a runtime and memory overhead.
This patch refactors this entirely and uses the lower layer API GDBusConnection
directly. It replaces the generated code, GDBusInterfaceSkeleton, and
GDBusObjectManagerServer. All this is now done by NMDbusObject and NMDBusManager
and static descriptor instances of type GDBusInterfaceInfo.
This adds a net plus of more then 1300 lines of hand written code. I claim
that this implementation is easier to understand. Note that previously we
also required extensive and complex glue code to bind our objects to the
generated skeleton objects. Instead, now glue our objects directly to
GDBusConnection. The result is more immediate and gets rid of layers of
code in between.
Now that the D-Bus glue us more under our control, we can address issus and
bottlenecks better, instead of adding code to bend the generated skeletons
to our needs.
Note that the current implementation now only supports one D-Bus connection.
That was effectively the case already, although there were places (and still are)
where the code pretends it could also support connections from a private socket.
We dropped private socket support mainly because it was unused, untested and
buggy, but also because GDBusObjectManagerServer could not export the same
objects on multiple connections. Now, it would be rather straight forward to
fix that and re-introduce ObjectManager on each private connection. But this
commit doesn't do that yet, and the new code intentionally supports only one
D-Bus connection.
Also, the D-Bus startup was simplified. There is no retry, either nm_dbus_manager_start()
succeeds, or it detects the initrd case. In the initrd case, bus manager never tries to
connect to D-Bus. Since the initrd scenario is not yet used/tested, this is good enough
for the moment. It could be easily extended later, for example with polling whether the
system bus appears (like was done previously). Also, restart of D-Bus daemon isn't
supported either -- just like before.
Note how NMDBusManager now implements the ObjectManager D-Bus interface
directly.
Also, this fixes race issues in the server, by no longer delaying
PropertiesChanged signals. NMExportedObject would collect changed
properties and send the signal out in idle_emit_properties_changed()
on idle. This messes up the ordering of change events w.r.t. other
signals and events on the bus. Note that not only NMExportedObject
messed up the ordering. Also the generated code would hook into
notify() and process change events in and idle handle, exhibiting the
same ordering issue too.
No longer do that. PropertiesChanged signals will be sent right away
by hooking into dispatch_properties_changed(). This means, changing
a property in quick succession will no longer be combined and is
guaranteed to emit signals for each individual state. Quite possibly
we emit now more PropertiesChanged signals then before.
However, we are now able to group a set of changes by using standard
g_object_freeze_notify()/g_object_thaw_notify(). We probably should
make more use of that.
Also, now that our signals are all handled in the right order, we
might find places where we still emit them in the wrong order. But that
is then due to the order in which our GObjects emit signals, not due
to an ill behavior of the D-Bus glue. Possibly we need to identify
such ordering issues and fix them.
Numbers (for contrib/rpm --without debug on x86_64):
- the patch changes the code size of NetworkManager by
- 2809360 bytes
+ 2537528 bytes (-9.7%)
- Runtime measurements are harder because there is a large variance
during testing. In other words, the numbers are not reproducible.
Currently, the implementation performs no caching of GVariants at all,
but it would be rather simple to add it, if that turns out to be
useful.
Anyway, without strong claim, it seems that the new form tends to
perform slightly better. That would be no surprise.
$ time (for i in {1..1000}; do nmcli >/dev/null || break; echo -n .; done)
- real 1m39.355s
+ real 1m37.432s
$ time (for i in {1..2000}; do busctl call org.freedesktop.NetworkManager /org/freedesktop org.freedesktop.DBus.ObjectManager GetManagedObjects > /dev/null || break; echo -n .; done)
- real 0m26.843s
+ real 0m25.281s
- Regarding RSS size, just looking at the processes in similar
conditions, doesn't give a large difference. On my system they
consume about 19MB RSS. It seems that the new version has a
slightly smaller RSS size.
- 19356 RSS
+ 18660 RSS
The condition was obviosly inverted, blocking autoconnect when
it should not, and not blocking it when it should.
[thaller@redhat.com: modified original patch and rewrite commit message]
Fixes: e2c8ef45achttps://bugzilla.gnome.org/show_bug.cgi?id=794014
XXX was used to either raise attention (NOTE) or to indicate
that this is ugly code that should be fixed (FIXME). The usage
was inconsistent.
Let's avoid XXX and use either NOTE or FIXME.
Don't track the per-device configuration in NMDnsManager by
the ifname, but by the ifindex. We should consistently treat
the ifindex as the ID of a link, like kernel does.
At the few places where we actually need the ifname, resolve
it by looking into the platform cache. That is not necessarily
the same as the ifname that is currently tracked by NMDevice,
because netdev interfaces can be renamed, and NMDevice updates
it's link properties delayed. However, the platform cache has
the most recent notion of the correct interface name for an
ifindex, so if we ever hit a race here, we do it now more
correctly.
This also temporarily drops support for mdns. Will be re-added next,
but differently.
"UNKNOWN" is not a good name. If you don't set the property
in the connection explicitly, it should be "DEFAULT".
Also, make "DEFAULT" -1. For one, that ensures that the enum's
underlying integer type is signed. Otherwise, it's cumbersome
to test "if (mdns >= DEFAULT)" because in case of unsigned types,
the compiler will warn about the check always being true.
Also, it allows for "NO" to be zero. These are no strong reasons,
but I tend to think this is better.
Also, don't make the property of NMSettingConnection a CONSTRUCT property.
Initialize the default manually in the init function.
Also, order the numeric values so that DEFAULT < NO < RESOLVE < YES with
YES being largest because it enables *the most*.
Update nm-policy.c and nm-dns-manager.c so that the connection-specific
settings get propagated to DNS manger. Currently the only such value is
the mDNS status.
Add update_mdns() function to DNS plugin interface. If a DNS plugin
supports mDNS, it can set an interface with a given index to support
mDNS resolving or also register the current hostname.
The mDNS support is currently added only to systemd-resolved DNS plugin.
Previously, NMPolicy would explicitly check whether the connection is not visible,
to skip autoconnect.
We have nm_settings_connection_autoconnect_is_blocked() function, that can do that.
The advantage is, that at various places we call nm_settings_connection_autoconnect_is_blocked()
to determine whether autoconnect is blocked. By declaring invisible connections
as blocked from autoconnect as well, we short-cut various autoconnection attempts,
that previoulsy only failed later during auto_activate_device().
The accessor functions just look whether a certain flag is set. As these
functions have a different name then the flags, this is more confusing
then helpful. For example, if you want to know where the NM_GENERATED
flag matters, you had to know to grep for nm_settings_connection_get_nm_generated()
in addition to NM_SETTINGS_CONNECTION_FLAGS_NM_GENERATED.
The accessor function hid that the property was implemented as
a connection flag. For example, it was not immediately obvious
that nm_settings_connection_get_nm_generated() is the same
as having the NM_SETTINGS_CONNECTION_FLAGS_NM_GENERATED flag
set.
Drop them.
We already need to re-emit the notify::flags signal.
It's cumbersome to do this for boolean properties, so
re-use the flags to also track the visibility state.
