If IWD connects under bad RF conditions and netconfig takes
a while to complete (e.g. slow DHCP), the roam timeout
could fire before DHCP is done. Then, after the roam,
IWD would transition automatically to connected before
DHCP was finished. In theory DHCP could still complete after
this point but any process depending on IWD's connected
state would be uninformed and assume IP networking is up.
Fix this by stopping netconfig prior to a roam if IWD is not
in a connected state. Then, once the roam either failed or
succeeded, start netconfig again.
Use a more appropriate printf conversion string in order to avoid
unnecessary implicit conversion which can lead to a buffer overflow.
Reasons similar to commit:
98b758f893 ("knownnetworks: fix printing SSID in hex")
In the case that the FT target is on the same channel as we're currently
operating on, use ft_authenticate_onchannel instead of ft_authenticate.
Going offchannel in this case can confuse some drivers.
Past commits should address any potential problems of the timer
firing during FT, but its still good practice to cancel the timer
once it is no longer needed, i.e. once FT has started.
If station has already started FT ensure station_cannot_roam takes
that into account. Since the state has not yet changed it must also
check if the FT work ID is set.
Under the following conditions IWD can accidentally trigger a second
roam scan while one is already in progress:
- A low RSSI condition is met. This starts the roam rearm timer.
- A packet loss condition is met, which triggers a roam scan.
- The roam rearm timer fires and starts another roam scan while
also overwriting the first roam scan ID.
- Then, if IWD gets disconnected the overwritten roam scan gets
canceled, and the roam state is cleared which NULL's
station->connected_network.
- The initial roam scan results then come in with the assumption
that IWD is still connected which results in a crash trying to
reference station->connected_network.
This can be fixed by adding a station_cannot_roam check in the rearm
timer. If IWD is already doing a roam scan station->preparing_roam
should be set which will cause it to return true and stop any further
action.
Aborting (signal 11) [/usr/libexec/iwd]
iwd[426]: ++++++++ backtrace ++++++++
iwd[426]: #0 0x7f858d7b2090 in /lib/x86_64-linux-gnu/libc.so.6
iwd[426]: #1 0x443df7 in network_get_security() at ome/locus/workspace/iwd/src/network.c:287
iwd[426]: #2 0x421fbb in station_roam_scan_notify() at ome/locus/workspace/iwd/src/station.c:2516
iwd[426]: #3 0x43ebc1 in scan_finished() at ome/locus/workspace/iwd/src/scan.c:1861
iwd[426]: #4 0x43ecf2 in get_scan_done() at ome/locus/workspace/iwd/src/scan.c:1891
iwd[426]: #5 0x4cbfe9 in destroy_request() at ome/locus/workspace/iwd/ell/genl.c:676
iwd[426]: #6 0x4cc98b in process_unicast() at ome/locus/workspace/iwd/ell/genl.c:954
iwd[426]: #7 0x4ccd28 in received_data() at ome/locus/workspace/iwd/ell/genl.c:1052
iwd[426]: #8 0x4c79c9 in io_callback() at ome/locus/workspace/iwd/ell/io.c:120
iwd[426]: #9 0x4c62e3 in l_main_iterate() at ome/locus/workspace/iwd/ell/main.c:476
iwd[426]: #10 0x4c6426 in l_main_run() at ome/locus/workspace/iwd/ell/main.c:519
iwd[426]: #11 0x4c6752 in l_main_run_with_signal() at ome/locus/workspace/iwd/ell/main.c:645
iwd[426]: #12 0x405987 in main() at ome/locus/workspace/iwd/src/main.c:600
iwd[426]: #13 0x7f858d793083 in /lib/x86_64-linux-gnu/libc.so.6
iwd[426]: +++++++++++++++++++++++++++
Rekeys for station mode don't need to know when complete since
there is nothing to do once done. AP mode on the other hand needs
to know if the rekey was successful in order to reset/set the next
rekey timer.
IWD was optimizing FT-over-DS by authenticating to multiple BSS's
at the time of connecting which then made future roams slightly
faster since they could jump right into association. So far this
hasn't posed a problem but it was reported that some AP's actually
enforce a reassociation timeout (included in 4-way handshake).
Hostapd itself does no such enforcement but anything external to
hostapd could monitor FT events and clear the cache if any exceeded
this timeout.
For now remove the early action frames and treat FT-over-DS the
same as FT-over-Air. In the future we could parse the reassociation
timeout, batch out FT-Action frames and track responses but for the
time being this just fix the issue at a small performance cost.
The previous commit added an invocation of known_networks_watch_add, but
never updated the module dependency graph.
Fixes: a793a41662 ("station, eapol: Set up eap-tls-common for session caching")
Use eap_set_peer_id() to set a string identifying the TLS server,
currently the hex-encoded SSID of the network, to be used as group name
and primary key in the session cache l_settings object. Provide pointers
to storage_eap_tls_cache_{load,sync} to eap-tls-common.c using
eap_tls_set_session_cache_ops(). Listen to Known Network removed
signals and call eap_tls_forget_peer() to have any session related to
the network also dropped from the cache.
The known frequency list may include frequencies that once were
allowed but are now disabled due to regulatory restrictions. Don't
include these frequencies in the roam scan.
These events are sent if IWD fails to authentiate
(ft-over-air-roam-failed) or if it falls back to over air after
failing to use FT-over-DS (try-ft-over-air)
If IPv4 setup fails and the netconfig logic gives up, continue as if the
connection had failed at earlier stages so that autoconnect can try the
next available network.
AP roaming was structured such that any AP roam request would
force IWD to roam (assuming BSS's were found in scan results).
This isn't always the best behavior since IWD may be connected
to the best BSS in range.
Only force a roam if the AP includes one of the 3 disassociation/
termination bits. Otherwise attempt to roam but don't set the
ap_directed_roaming flag which will allows IWD to stay with the
current BSS if no better candidates are found.
There are a few checks that can be done prior to parsing the
request, in addition the explicit check for preparing_roam was
removed since this is taken care of by station_cannot_roam().
This both adds proper handling to the new roaming logic and fixes
a potential bug with firmware roams.
The new way roaming works doesn't use a connect callback. This
means that any disconnect event or call to netdev_connect_failed
will result in the event handler being called, where before the
connect callback would. This means we need to handle the ROAMING
state in the station disconnect event so IWD properly disassociates
and station goes out of ROAMING.
With firmware roams netdev gets an event which transitions station
into ROAMING. Then netdev issues GET_SCAN. During this time a
disconnect event could come in which would end up in
station_disconnect_event since there is no connect callback. This
needs to be handled the same and let IWD transition out of the
ROAMING state.
This converts station to using ft_action/ft_authenticate and
ft_associate and dropping the use of the netdev-only/auth-proto
logic.
Doing this allows for more flexibility if FT fails by letting
IWD try another roam candidate instead of disconnecting.
The current behavior is to only find the best roam candidate, which
generally is fine. But if for whatever reason IWD fails to roam it
would be nice having a few backup BSS's rather than having to
re-scan, or worse disassociate and reconnect entirely.
This patch doesn't change the roam behavior, just prepares for
using a roam candidate list. One difference though is any roam
candidates are added to station->bss_list, rather than just the
best BSS. This shouldn't effect any external behavior.
The candidate list is built based on scan_bss rank. First we establish
a base rank, the rank of the current BSS (or zero if AP roaming). Any
BSS in the results with a higher rank, excluding the current BSS, will
be added to the sorted station->roam_bss_list (as a new 'roam_bss'
entry) as well as stations overall BSS list. If the resulting list is
empty there were no better BSS's, otherwise station can now try to roam
starting with the best candidate (head of the roam list).
There may be situations (due to Multi-BSS operation) where an AP might
be advertising multiple SSIDs on the same BSSID. It is thus more
correct to lookup the preauthentication target on the network object
instead of the station bss_list. It used to be that the network list of
bsses was not updated when roam scan was performed. Hence the lookup
was always performed on the station bss_list. But this is no longer the
case, so it is safer to lookup on the network object directly on the
network.
FT is now driven (mostly) by station which removes the connect
callback. Instead once FT is completed, keys set, etc. netdev
will send an event to notify station.
This will make the debug API more robust as well as fix issues
certain drivers have when trying to roam. Some of these drivers
may flush scan results after CMD_CONNECT which results in -ENOENT
when trying to roam with CMD_AUTHENTICATE unless you rescan
explicitly.
Now this will be taken care of automatically and station will first
scan for the BSS (or full scan if not already in results) and
attempt to roam once the BSS is seen in a fresh scan.
The logic to replace the old BSS object was factored out into its
own function to be shared by the non-debug roam scan. It was also
simplified to just update the network since this will remove the
old BSS if it exists.
This adds a new netdev event for packet loss notifications from
the kernel. Depending on the scenario a station may see packet
loss events without any other indications like low RSSI. In these
cases IWD should still roam since there is no data flowing.
Some APs use an older hostapd OWE implementation which incorrectly
derives the PTK. To work around this group 19 should be used for
these APs. If there is a failure (reason=2) and the AKM is OWE
set force default group into network and retry. If this has been
done already the behavior is no different and the BSS will be
blacklisted.
The kernel handles setting the regulatory domain by receiving beacons
which set the country IE. Presumably since most regulatory domains
disallow 6GHz the default (world) domain also disables it. This means
until the country is set, 6GHz is disabled.
This poses a problem for IWD's quick scanning since it only scans a few
frequencies and this likely isn't enough beacons for the firmware to
update the country, leaving 6Ghz inaccessable to the user without manual
intervention (e.g. iw scan passive, or periodic scans by IWD).
To try and work around this limitation the quick scan logic has been
updated to check if a 6GHz AP has been connected to before and if that
frequency is disabled (but supported). If this is the case IWD will opt
for a full passive scan rather than scanning a limited set of
frequencies.
Provides useful information on why a roam might have failed, such as
failing to find the BSS or the BSS being ranked lower, and why that
might be.
The output format is the same as station_add_seen_bss for consistency.
Certain module dependencies were missing, which could cause a crash on
exit under (very unlikely) circumstances.
#0 l_queue_peek_head (queue=<optimized out>) at ../iwd-1.28/ell/queue.c:241
#1 0x0000aaaab752f2a0 in wiphy_radio_work_done (wiphy=0xaaaac3a129a0, id=6)
at ../iwd-1.28/src/wiphy.c:2013
#2 0x0000aaaab7523f50 in netdev_connect_free (netdev=netdev@entry=0xaaaac3a13db0)
at ../iwd-1.28/src/netdev.c:765
#3 0x0000aaaab7526208 in netdev_free (data=0xaaaac3a13db0) at ../iwd-1.28/src/netdev.c:909
#4 0x0000aaaab75a3924 in l_queue_clear (queue=queue@entry=0xaaaac3a0c800,
destroy=destroy@entry=0xaaaab7526190 <netdev_free>) at ../iwd-1.28/ell/queue.c:107
#5 0x0000aaaab75a3974 in l_queue_destroy (queue=0xaaaac3a0c800,
destroy=destroy@entry=0xaaaab7526190 <netdev_free>) at ../iwd-1.28/ell/queue.c:82
#6 0x0000aaaab7522050 in netdev_exit () at ../iwd-1.28/src/netdev.c:6653
#7 0x0000aaaab7579bb0 in iwd_modules_exit () at ../iwd-1.28/src/module.c:181
In this particular case, wiphy module was de-initialized prior to the
netdev module:
Jul 14 18:14:39 localhost iwd[2867]: ../iwd-1.28/src/wiphy.c:wiphy_free() Freeing wiphy phy0[0]
Jul 14 18:14:39 localhost iwd[2867]: ../iwd-1.28/src/netdev.c:netdev_free() Freeing netdev wlan0[45]
station_signal_agent_notify() has been refactored so that its usage is
simpler. station_rssi_level_changed() has been replaced by an inlined
call to station_signal_agent_notify().
ConnectHiddenNetwork creates a temporary network object and initiates a
connection with it. If the connection fails (due to an incorrect
passphrase or other reasons), then this temporary object is destroyed.
Delay its destruction until network_disconnected() since
network_connect_failed is called too early. Also, re-order the sequence
in station_reset_connection_state() in order to avoid using the network
object after it has been freed by network_disconnected().
Fixes: 85d9d6461f ("network: Hide hidden networks on connection error")
If a user connection fails on a freshly scanned psk or open hidden
network, during passphrase request or after, it shall be removed from
the network list. Otherwise, it would be possible to directly connect
to that known network, which will appear as not hidden.
The logic here assumed any BSS's in the roam scan were identical to
ones in station's bss_list with the same address. Usually this is true
but, for example, if the BSS changed frequency the one in station's
list is invalid.
Instead when a match is found remove the old BSS and re-insert the new
one.
