This is being done to allow the DPP module to work correctly. DPP
currently uses __station_connect_network incorrectly since it
does not (and cannot) change the state after calling. The only
way to connect with a state change is via station_connect_network
which requires a DBus method that triggered the connection; DPP
does not have this due to its potentially long run time.
To support DPP there are a few options:
1. Pass a state into __station_connect_network (this patch)
2. Support a NULL DBus message in station_connect_network. This
would require several NULL checks and adding all that to only
support DPP just didn't feel right.
3. A 3rd connect API in station which wraps
__station_connect_network and changes the state. And again, an
entirely new API for only DPP felt wrong (I guess we did this
for network_autoconnect though...)
Its about 50/50 between call sites that changed state after calling
and those that do not. Changing the state inside
__station_connect_network felt useful enough to cover the cases that
could benefit and the remaining cases could handle it easily enough:
- network_autoconnect(), and the state is changed by station after
calling so it more or less follows the same pattern just routes
through network. This will now pass the CONNECTING_AUTO state
from within network vs station.
- The disconnect/reconnect path. Here the state is changed to
ROAMING prior in order to avoid multiple state changes. Knowing
this the same ROAMING state can be passed which won't trigger a
state change.
- Retrying after a failed BSS. The state changes on the first call
then remains the same for each connection attempt. To support this
the current station->state is passed to avoid a state change.
With the addition of OWE transition network needs to be notified
of the hidden OWE scan which is quite similar to how it is notified
of ANQP. The ANQP event watch can be made generic and reused to
allow other events besides ANQP.
This will be effectively the same as the CONNECTING state, but can be
used to enable differing behavior, depending on whether connection was
triggered by autoconnect or via D-Bus.
Logically this frame watch belongs in station. It was kept in device.c
for the purported reason that the station object was removed with
ifdown/ifup changes and hence the frame watch might need to be removed
and re-added unnecessarily. Since the kernel does not actually allow to
unregister a frame watch (only when the netdev is removed or its iftype
changes), re-adding a frame watch might trigger a -EALREADY or similar
error.
Avoid this by registering the frame watch when a new netdev is detected
in STATION mode, or when the interface type changes to STATION.
Instead of manually managing whether to expire BSSes or not, use the
scanned frequency set instead. This makes the API slightly easier to
understand (dropping two boolean arguments in a row) and also a bit more
future-proof.
If we forget a hidden network, then make sure to remove it from the
network list completely. Otherwise it would be possible to still
issue a Network.Connect to that particular object, but the fact that the
network is hidden would be lost.
Add a parameter to station_set_scan_results to allow skipping the
removal of old BSSes. In the DBus-triggered scan only expire BSSes
after having gone through the full supported frequency set.
It should be safe to pass partial scan results to
station_set_scan_results() when not expiring BSSes so using this new
parameter I guess we could also call it for roam scan results.
This is to allow network to watch for ANQP activity in order to
fix the race condition between scanning finishing and ANQP finishing.
Without this it is possible for a DBus Connect() to come in before
ANQP has completed and causing the network to return NotConfigured,
when its actually in the process of obtaining all the network info.
The watch was made globally in station due to network not having
a station object until each individual network is created. Adding a
watch during network creation would result in many watchers as well
as a lot of removal/addition as networks are found and lost.
For Radio Resource Management (RRM) we will need access to the currently
connected BSS as well as the last scan results in order to do certain
kinds of requested measurements.
The auto-connect state will now consist of the two phases:
STATION_STATE_AUTOCONNECT_QUICK and STATION_STATE_AUTOCONNECT_FULL.
The auto-connect will always start with STATION_STATE_AUTOCONNECT_QUICK
and then transition into STATION_STATE_AUTOCONNECT_FULL if no
connection has been established. During STATION_STATE_AUTOCONNECT_QUICK
phase we take advantage of the wireless scans with the limited number
of channels on which the known networks have been observed before.
This approach allows to shorten the time required for the network
sweeps, therefore decreases the connection latency if the connection
is possible. Thereafter, if no connection has been established after
the first phase we transition into STATION_STATE_AUTOCONNECT_FULL and
do the periodic scan just like we did before the split in
STATION_STATE_AUTOCONNECT state.
Move the roam initiation (signal loss, ap directed roaming) and scanning
details into station from device. Certain device functions have been
exposed temporarily to make this possible.