[PATCH] wpa_supplicant: dBus: Flush Sate Property Change

[Arowa Suliman]

Hi Jouni,

I ran the dbus_roam test 50 times, both with and without the State
flush modification. In both scenarios, the test consistently failed,
and the CurrentBSS property was sent prior to State=completed. Given
these results, is it fine to merge this change?

Logs from one of the runs without the change:
2024-07-15 14:26:02,729 DEBUG propertiesChanged:
dbus.Dictionary({dbus.String('State'): dbus.String('authenticating',
variant_level=1), dbus.String('CurrentAuthMode'):
dbus.String('WPA2-PSK+WPA-PSK', variant_level=1)},
signature=dbus.Signature('sv'))
2024-07-15 14:26:02,750 DEBUG propertiesChanged:
dbus.Dictionary({dbus.String('State'): dbus.String('associating',
variant_level=1), dbus.String('AuthStatusCode'): dbus.Int32(0,
variant_level=1)}, signature=dbus.Signature('sv'))
2024-07-15 14:26:02,791 DEBUG propertiesChanged:
dbus.Dictionary({dbus.String('State'): dbus.String('associated',
variant_level=1), dbus.String('CurrentBSS'):
dbus.ObjectPath('/fi/w1/wpa_supplicant1/Interfaces/0/BSSs/2',
variant_level=1), dbus.String('CurrentAuthMode'):
dbus.String('WPA2-PSK+WPA-PSK', variant_level=1)},
signature=dbus.Signature('sv'))
2024-07-15 14:26:02,850 DEBUG propertiesChanged:
dbus.Dictionary({dbus.String('State'): dbus.String('4way_handshake',
variant_level=1)}, signature=dbus.Signature('sv'))
2024-07-15 14:26:02,937 DEBUG propertiesChanged:
dbus.Dictionary({dbus.String('State'): dbus.String('completed',
variant_level=1), dbus.String('CurrentAuthMode'):
dbus.String('WPA2-PSK+WPA-PSK', variant_level=1)},
signature=dbus.Signature('sv'))
2024-07-15 14:26:02,940 ERROR Exception in handler for D-Bus signal:
Traceback (most recent call last):
  File "/usr/lib/python3.8/site-packages/dbus/connection.py", line
232, in maybe_handle_message
    self._handler(*args, **kwargs)
  File "/usr/local/libexec/hostap/tests/hwsim/test_dbus.py", line
6070, in propertiesChanged
    cur = properties["CurrentBSS"]
KeyError: 'CurrentBSS'

Thanks,
Arowa

On Mon, Mar 11, 2024 at 1:42 PM Arowa Suliman <arowa at chromium.org> wrote:
>
> On Sun, Mar 3, 2024 at 11:38 AM Jouni Malinen <j at w1.fi> wrote:
> >
> > On Wed, Feb 07, 2024 at 05:02:40PM -0800, Arowa Suliman wrote:
> > > The "State" property in wpa_supplicant helps track important WiFi
> > > connection events (like when the security key is being updated).
> > > Currently, updates to this property aren't always sent right away. This
> > > delay can make it difficult to accurately track the different stages of
> > > the connection process.
> > >
> > > This change ensures that any updates to the "State" property are sent
> > > immediately. This will provide a more accurate and real-time view of the
> > > WiFi connection process.
> >
> > This change breaks a couple of automated test cases: dbus_roam and
> > dbus_remove_connected. It looks like at least the dbus_roam case is
> > something that could result in breaking some deployed use cases due to
> > modified behavior. The PropertiesChanged event that indicates
> > State=completed could now go out without CurrentBSS being set. That
> > seems undesired or at least would require more careful consideration of
> > existing users of the interface and clear documentation of the potential
> > risks in the commit message.
>
> I checked the failures in both tests and the reason for these failures
> is the assumption that the State and CurrentBSS properties are always
> sent together. After modifying the two tests to wait for these
> properties separately the tests are passing. Even without my change
> there is still a possibility that the properties could be sent
> separately. For example the state property changes right before
> WPA_DBUS_SEND_PROP_CHANGED_TIMEOUT and current BSS changes right after
> that.