Once we know the outcome of the check, just return it instead of
falling though to return a variable "good" which was initialized
two pages earlier.
Also, avoid the "default" switch case. This way, we get a compiler
warning about missing enum values.
Keyfile support was initially added under GPL-2.0+ license as part of
core. It was moved to "libnm-core" in commit 59eb5312a5 ('keyfile: merge
branch 'th/libnm-keyfile-bgo744699'').
"libnm-core" is statically linked with by core and "libnm". In
the former case under terms of GPL-2.0+ (good) and in the latter case
under terms of LGPL-2.1+ (bad).
In fact, to this day, "libnm" doesn't actually use the code. The linker
will probably remove all the GPL-2.0+ symbols when compiled with
gc-sections or LTO. Still, linking them together in the first place
makes "libnm" only available under GPL code (despite the code
not actually being used).
Instead, move the GPL code to a separate static library
"shared/nm-keyfile/libnm-keyfile.la" and only link it to the part
that actually uses the code (and which is GPL licensed too).
This fixes the license violation.
Eventually, it would be very useful to be able to expose keyfile
handling via "libnm". However that is not straight forward due to the
licensing conflict.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/merge_requests/381
Move it to shared as it's useful for clients as well.
Move and rename nm_dbus_manager_new_auth_subject_from_context() and
nm_dbus_manager_new_auth_subject_from_message() in nm-dbus-manager.c
as they're needed there.
The method field is set from (only) via a GObject property setter,
which sets a value of type int. As we afterwards validate that the
value is in a valid range, we should use a suitable type to hold
the value to begin with. Of course, in almost all cases is the
underlying type of the enum already int.
G_PARAM_CONSTRUCT cause to explicitly initialize the property during
object construction. This is an unnecessary overhead that we can easily
avoid.
The overhead is because G_PARAM_CONSTRUCT parameters are always set with
g_object_set() before calling constructed(). Even if they are not specified
during g_object_new(), in which case it calls set with the property's default
value. This also requires g_object_new() to iterate all properties to
find and sort the construct properties.
NMSetting are supposed to be simple classes. They don't need to have
their properties initialized before object construction completes.
Especially if the default values are NULL or zero, in which case there
is nothing to do. If the default value is not NULL or zero, we need
to initialize the field instead in the nm_setting*_init() function.
Otherwise, this function cannot really be used via generated bindings.
Also, it's the only way to actually retrieve the set vlan-ids, without
it, you wouldn't know which ones are set.
Fixes: a9b4532fa7 ('libnm-core: add SR-IOV setting')
LLMNR and mDNS settings can have their global default value configured
in "NetworkManager.conf".
Global default values should work the way that all regular values of the property
can be configured explicitly in the connection profile. The special "default" value
only indicates to allow lookup of the global default, but it should not have a
meaning of its own.
Note that if mDNS/LLMNR settings are left unspecified, we will set the
argument to SetLinkMulticastDNS() and SetLinkLLMNR() functions to "",
which means that systemd-resolved decides on a default. Also, depending
on the DNS plugin, the default value differs. This is all fine however.
In this case, the ultimate default value depends on other things (like
the DNS plugin), but each possible value is in fact explicitly
configurable. We also do that for "ipv6.ip6-privacy".
Anyway, cleanup the documentation a bit and try to better explain what
the default is.
Not being able to compare two NMIPAddress instances is a major
limitation. Add nm_ip_address_cmp_full(). The choice here for adding
a "cmp()" function instead of a "equals()" function is that cmp is
more useful. We only want to add one of the two, so choose the
more powerful one. Yes, usually its also not the variant we want
or the variant that is convenient to use, such is life.
Compare this to:
- nm_ip_route_equal_full(), which is an equal() method and not
a cmp().
- nm_ip_route_equal_full() which has a guint flags argument,
instead of a typedef for an enum, with a proper generated
GType.
- systemd-networkd and initscripts both support it.
- it seems suggested to configure routes with scope "link" on AWS.
- the scope is only supported for IPv4 routes. Kernel ignores the
attribute for IPv6 routes.
- we don't support the aliases like "link" or "global". Instead
only the numeric value is supported. This is different from
systemd-networkd, which accepts names like "global" and "link",
but no numerical values. I think restricting ourself only to
the aliases unnecessarily limits what is possible on netlink.
The alternative would be to allow aliases and numbers both,
but that causes multiple ways to define something and has
thus downsides. So, only numeric values.
- when setting rtm_scope to RT_SCOPE_NOWHERE (0, the default), kernel
will coerce that to RT_SCOPE_LINK. This ambiguity of nowhere vs. link
is a problem, but we don't do anything about it.
- The other problem is, that when deleting a route with scope RT_SCOPE_NOWHERE,
this acts as a wild care and removes the first route that matches (given the
other route attributes). That means, NetworkManager has no meaningful
way to delete a route with scope zero, there is always the danger that
we might delete the wrong route. But this is nothing new to this
patch. The problem existed already previously, except that
NetworkManager could only add routes with scope nowhere (i.e. link).
We will rework NMClient entirely. Then, the synchronous initialization will also use
the asynchronous code paths. The difference will be that with synchronous initialization,
all D-Bus interaction will be done with an internal GMainContext as current thread default,
and that internal context will run until initialization completes.
Note that even after initialization completes, it cannot be swapped back to the user's
(outer) GMainContext. That is because contexts are essentially the queue for our
D-Bus events, and we cannot swap from one queue to the other in a race
free manner (or a full resync). In other words, the two contexts are not in sync,
so after using the internal context NMClient needs to stick to that (at least, until
the name owner gets lost, which gives an opportunity to resync and switch back to the
user's main context).
We thus need to hook the internal (inner) GMainContext with the user's (outer) context,
so when the user iterates the outer context, events on the inner context get dispatched.
Add nm_utils_g_main_context_create_integrate_source() to create such a GSource for
integrating two contexts.
Note that the use-case here is limited: the integrated, inner main context must
not be explicitly iterated except from being dispatched by the integrating
source. Otherwise, you'd get recursive runs, possible deadlocks and general
ugliness. NMClient must show restrain how to use the inner context while it is
integrated.
Add a new 'carrier' flag to the InterfaceFlags property of devices to
indicate the current carrier state.
The new flag is equivalent to the 'lower-up' flag for all devices
except the ones that use a non-standard carrier detection mechanism
like NMDeviceAdsl.
Add a new read-only "InterfaceFlags" property to the Device interface
to export via D-Bus kernel flags and possibly other NM specific
flags. At the moment IFF_UP and IFF_LOWERUP are implemented.
This essentially aligns the implementation with the documentation.
It is also rather useful, since it allows us to use the value returned
by nm_setting_wired_get_mac_address() directly, and that one can indeed
be NULL.
The only contributors to this code are Red Hat employees who agree
with this license change.
$ git log --pretty=format:'%Cred%h%Creset - %Cgreen(%ai)%Creset [%C(yellow)%an%Creset] %s%C(yellow)%d%Creset' --no-merges -- 'libnm-core/nm-json.?' 'libnm-core/nm-jansson.?'
...
$ git shortlog -s --no-merges -- 'libnm-core/nm-json.?' 'libnm-core/nm-jansson.?'
1 Beniamino Galvani
1 Lubomir Rintel
8 Thomas Haller
Signed-off-by: Beniamino Galvani <bgalvani@redhat.com>
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Thomas Haller <thaller@redhat.com>
The library should not print to stdout/stderr. This function is used to
convert untrusted(!!) input to a normalized and sanitized strv array.
g_warning() is essentially an assertion, and it's wrong to do that
for untrusted data. If the caller had to pre-validate the array, then
having this function would be pointless.
Note that D-Bus is fundamentally asynchronous. Doing blocking calls
on top of D-Bus is odd, especially for libnm's NMClient. That is because
NMClient essentially is a client-side cache of the objects from the D-Bus
interface. This cache should be filled exclusively by (asynchronous) D-Bus
events (PropertiesChanged). So, making a blocking D-Bus call means to wait
for a response and return it, while queuing all messages that are received
in the meantime.
Basically there are three ways how a synchronous API on NMClient could behave:
1) the call just calls g_dbus_connection_call_sync(). This means
that libnm sends a D-Bus request via GDBusConnection, and blockingly
waits for the response. All D-Bus messages that get received in the
meantime are queued in the GMainContext that belongs to NMClient.
That means, none of these D-Bus events are processed until we
iterate the GMainContext after the call returns. The effect is,
that NMClient (and all cached objects in there) are unaffected by
the D-Bus request.
Most of the synchronous API calls in libnm are of this kind.
The problem is that the strict ordering of D-Bus events gets
violated.
For some API this is not an immediate problem. Take for example
nm_device_wifi_request_scan(). The call merely blockingly tells
NetworkManager to start scanning, but since NetworkManager's D-Bus
API does not directly expose any state that tells whether we are
currently scanning, this out of order processing of the D-Bus
request is a small issue.
The problem is more obvious for nm_client_networking_set_enabled().
After calling it, NM_CLIENT_NETWORKING_ENABLED is still unaffected
and unchanged, because the PropertiesChanged signal from D-Bus
is not yet processed.
This means, while you make such a blocking call, NMClient's state
does not change. But usually you perform the synchronous call
to change some state. In this form, the blocking call is not useful,
because NMClient only changes the state after iterating the GMainContext,
and not after the blocking call returns.
2) like 1), but after making the blocking g_dbus_connection_call_sync(),
update the NMClient cache artificially. This is what
nm_manager_check_connectivity() does, to "fix" bgo#784629.
This also has the problem of out-of-order events, but it kinda
solves the problem of not changing the state during the blocking
call. But it does so by hacking the state of the cache. I think
this is really wrong because the state should only be updated from
the ordered stream of D-Bus messages (PropertiesChanged signal and
similar). When libnm decides to modify the state, there may be already
D-Bus messages queued that affect this very state.
3) instead of calling g_dbus_connection_call_sync(), use the
asynchronous g_dbus_connection_call(). If we would use a sepaate
GMainContext for all D-Bus related calls, we could ensure that
while we block for the response, we iterate that internal main context.
This might be nice, because all events are processed in order and
after the blocking call returns, the NMClient state is up to date.
The are problems however: current blocking API does not do this,
so it's a significant change in behavior. Also, it might be
unexpected to the user that during the blocking call the entire
content of NMClient's cache might change and all pointers to the
cache might be invalidated. Also, of course NMClient would invoke
signals for all the changes that happen.
Another problem is that this would be more effort to implement
and it involves a small performance overhead for all D-Bus related
calls (because we have to serialize all events in an internal
GMainContext first and then invoke them on the caller's context).
Also, if the users wants this behavior, they could implement it themself
by running libnm in their own GMainContext. Note that libnm might
have bugs to make that really working, but that should be fixed
instead of adding such synchrnous API behavior.
Read also [1], for why blocking calls are wrong.
[1] https://smcv.pseudorandom.co.uk/2008/11/nonblocking/
So, all possible behaviors for synchronous API have severe behavioural
issues. Mark all this API as deprecated. Also, this serves the purpose of
identifying blocking D-Bus calls in libnm.
Note that "deprecated" here does not really mean that the API is going
to be removed. We don't break API. The user may:
- continue to use this API. It's deprecated, awkward and discouraged,
but if it works, by all means use it.
- use asynchronous API. That's the only sensible way to use D-Bus.
If libnm lacks a certain asynchronous counterpart, it should be
added.
- use GDBusConnection directly. There really isn't anything wrong
with D-Bus or GDBusConnection. This deprecated API is just a wrapper
around g_dbus_connection_call_sync(). You may call it directly
without feeling dirty.
---
The only other remainging API is the synchronous GInitable call for
NMClient. That is an entirely separate beast and not particularly
wrong (from an API point of view).
Note that synchronous API in NMSecretAgentOld, NMVpnPluginOld and
NMVpnServicePlugin as not deprecated here. These types are not part
of the D-Bus cache and while they have similar issues, it's less severe
because they have less state.
There are different enum files created that make use of different
template files. However, `mkenums_simple` method allows the creation
of the same enum files without the need of template files.
The creation of the `nm-core-enum-types` and
`nm-core-tests-enum-types` use now `mkenums_simple` so template
files are now unnecessary.
