The advantage of environment variables is that the user can use
`systemctl edit NetworkManager-dispatcher.service` for setting them,
without need to change the ExecStart= line.
Also, enabling debugging from the start is useful, despite that debug
logging can be enabled per-request.
Also, there is a difference whether we want verbose logging or whether
we want to log to stdout. There should be a flag, that only increases the
logging verbosity, but does not change the logging backend.
NetworkManager runs as root and has lots of capabilities.
We want to reduce the attach surface by dropping capabilities,
but there is a genuine need to do certain things.
For example, we currently require dac_override capability, to open
the unix socket of ovsdb. Most users wouldn't use OVS, so we should
find a way to not require that dac_override capability. The solution
is to have a separate, D-Bus activate service (nm-sudo), which
has the capability to open and provide the file descriptor.
For authentication, we only rely on D-Bus. We watch the name owner
of NetworkManager, and only accept requests from that service. We trust
D-Bus to get it right a request from that name owner is really coming
from NetworkManager. If we couldn't trust that, how could PolicyKit
or any authentication via D-Bus work? For testing, the user can set
NM_SUDO_NO_AUTH_FOR_TESTING=1.
https://bugzilla.redhat.com/show_bug.cgi?id=1921826
$ nmcli connection add type dummy con-name x autoconnect no ipv4.method disabled ipv6.method disabled ifname d0
$ ip link add d1 type dummy
$ nmcli connection up x ifname d1
Error: device 'd1' not compatible with connection 'x': The interface names of the device and the connection didn't match..
This file is not actually to be used by NetworkManager itself.
Instead, every (glib based) VPN plugin will want something like this,
hence we have a copy here.
Move it to a new directory "src/contrib/".
"libnm-core/" is rather complicated. It provides a static library that
is linked into libnm.so and NetworkManager. It also contains public
headers (like "nm-setting.h") which are part of public libnm API.
Then we have helper libraries ("libnm-core/nm-libnm-core-*/") which
only rely on public API of libnm-core, but are themself static
libraries that can be used by anybody who uses libnm-core. And
"libnm-core/nm-libnm-core-intern" is used by libnm-core itself.
Move "libnm-core/" to "src/". But also split it in different
directories so that they have a clearer purpose.
The goal is to have a flat directory hierarchy. The "src/libnm-core*/"
directories correspond to the different modules (static libraries and set
of headers that we have). We have different kinds of such modules because
of how we combine various code together. The directory layout now reflects
this.
Before there was a licensing conflict between the keyfile code
(libnm-keyfile) and libnm. The latter would require LGPL-2.1+ while
keyfile code was GPL-2.0+.
Consequently we were linking libnm-keyfile into the daemon, but not in
libnm.so.
This conflict has been resolved and keyfile API is part of libnm.so.
There is no more need to build a separate (intermediary) library. Merge
them.
This also makes sense because keyfile code needs access to private code
from libnm-core. It is closely tied to libnm-core, so that building them
separate makes no sense (anymore).
Currently "src/" mostly contains the source code of the daemon.
I say mostly, because that is not true, there are also the device,
settings, wwan, ppp plugins, the initrd generator, the pppd and dhcp
helper, and probably more.
Also we have source code under libnm-core/, libnm/, clients/, and
shared/ directories. That is all confusing.
We should have one "src" directory, that contains subdirectories. Those
subdirectories should contain individual parts (libraries or
applications), that possibly have dependencies on other subdirectories.
There should be a flat hierarchy of directories under src/, which
contains individual modules.
As the name "src/" is already taken, that prevents any sensible
restructuring of the code.
As a first step, move "src/" to "src/core/". This gives space to
reorganize the code better by moving individual components into "src/".
For inspiration, look at systemd's "src/" directory.
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/743
We want to move platform code to "shared/nm-platform". However, platform
code uses the logging infrastructure from the daemon, there is thus
an odd circular dependency.
Solve that by moving the "src/nm-logging.[hc]" to a new helper library
in "shared/nm-log-core".
NetworkManager is now able to configure veth interfaces throught the
NMSettingVeth. Veth interfaces only have "peer" property.
In order to support Veth interfaces in NetworkManager the design need
to pass the following requirements:
* Veth setting only has "peer" attribute.
* Ethernet profiles must be applicable to Veth interfaces.
* When creating a veth interface, the peer will be managed by
NetworkManager but will not have a profile.
* Veth connection can reapply only if the peer has not been modified.
* In order to modify the veth peer, NetworkManager must deactivate the
connection and create a new one with peer modified.
In general, it should support the basis of veth interfaces but without
breaking any existing feature or use case. The users that are using veth
interfaces as ethernet should not notice anything changed unless they
specified the veth peer setting.
Creating a Veth interface in NetworkManager is useful even without the
support for namespaces for some use cases, e.g "connecting one side of
the veth to an OVS bridge and the other side to a Linux bridge" this is
done when using OVN kubernetes [1][2]. In addition, it would provide
persistent configuration and rollback support for Veth interfaces.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1885605
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1894139
Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
"XXX" is used for tagging parts of code that still need work before
merging a patch. If you want to highlight/mark a comment which is merged
use either "TODO" or "FIXME".
Of course, even "TODO" and "FIXME" should be avoided in favor of just
doing/fixing it. Such things tend to never be done/fixed.
