This will help to get rid of magic number use throughout the project.
The definitions should be limited to global magic numbers that are used
throughout the project, for example SSID length, MAC address length,
etc.
Caught by static analysis, if ATTR_MAC was not in the message there
would be a memcpy with uninitialized bytes. In addition there is no
reason to memcpy twice. Instead 'mac' can be a const pointer which
both verifies it exists and removes the need for a second memcpy.
Static analysis complains that 'last' could be NULL which is true.
This really could only happen if every frequency was disabled which
likely is impossible but in any case, check before dereferencing
the pointer.
While here, also get rid of netdev_del_station. The only user of this
function was in ap.c and it could easily be replaced by invoking the new
nl80211_build_del_station function. The callback used by
netdev_build_del_station only printed an error and didn't do anything
useful. Get rid of it for now.
This mispelling was present in the configuration, so I retained parsing
of the legacy BandModifier*Ghz options for compatibility. Without this
change anyone spelling GHz correctly in their configs would be very
confused.
The extra IE length for the WMM IE was being set to 26 which is
the HT IE length, not WMM. Fix this and use the proper size for
the WMM IE of 50 bytes.
This shouldn't have caused any problems prior as the tail length
is always allocated with 256 or 512 extra bytes of headroom.
This adds support for rekeys to AP mode. A single timer is used and
reset to the next station needing a rekey. A default rekey timer of
600 seconds is used unless the profile sets a timeout.
This adds a builder which sets the country IE in probes/beacons.
The IE will use the 'single subband triplet sequence' meaning
dot11OperatingClassesRequired is false. This is much easier to
build and doesn't require knowing an operating class.
The IE itself is variable in length and potentially could grow
large if the hardware has a weird configuration (many different
power levels or segmentation in supported channels) so the
overall builder was changed to take the length of the buffer and
warnings will be printed if any space issues are encountered.
If supported this will include the HT capabilities and HT
operations elements in beacons/probes. Some shortcuts were taken
here since not all the information is currently parsed from the
hardware. Namely the HT operation element does not include the
basic MCS set. Still, this will at least show stations that the
AP is capable of more than just basic rates.
The builders themselves are structured similar to the basic rates
builder where they build only the contents and return the length.
The caller must set the type/length manually. This is to support
the two use cases of using with an IE builder vs direct pointer.
To include HT support a chandef needs to be created for whatever
frequency is being used. This allows IWD to provide a secondary
channel to the kernel in the case of 40MHz operation. Now the AP
will generate a chandef when starting based on the channel set
in the user profile (or default).
If HT is not supported the chandef width is set to 20MHz no-HT,
otherwise band_freq_to_ht_chandef is used.
The WMM parameter IE is expected by the linux kernel for any AP
supporting HT/VHT etc. IWD won't actually use WMM and its not
clear exactly why the kernel uses this restriction, but regardless
it must be included to support HT.
The supported rates IE was being built in two places. This makes that
code common. Unfortunately it needs to support both an ie builder
and using a pointer directly which is why it only builds the contents
of the IE and the caller must set the type/length.
This enables IWD to use 5GHz frequencies in AP mode. Currently
6GHz is not supported so we can assume a [General].Channel value
36 or above indicates the 5GHz band.
It should be noted that the system will probably need a regulatory
domain set in order for 5GHz to be allowed in AP mode. This is due
to world roaming (00) restricting any/all 5GHz frequencies. This
can be accomplished by setting main.conf [General].Country=CC to
the country this AP will operate in.
A comma separated list as a string was ok for pure display purposes
but if any processing needed to be done on these values by external
consumers it really makes more sense to use a DBus array.
This wasn't being updated meaning the property is missing until a
scan is issued over DBus.
Rather than duplicate all the property changed calls they were all
factored out into a helper function.
These can now be optionally provided in an AP profile and provide a
way to limit what ciphers can be chosen. This still is dependent on
what the hardware supports.
Certain drivers support/require probe response offloading which
IWD did not check for or properly handle. If probe response
offloading is required the probe response frame watch will not
be added and instead the ATTR_PROBE_RESP will be included with
START_AP.
The head/tail builders were reused but slightly modified to check
if the probe request frame is NULL, since it will be for use with
START_AP.
This fixes a crash associated with toggling the iftype to AP mode
then calling GetDiagnostics. The diagnostic interface is never
cleaned up when netdev goes down so DBus calls can still be made
which ends up crashing since the AP interface objects are no longer
valid.
Running the following iwctl commands in a script (once or twice)
triggers this crash reliably:
iwctl device wlp2s0 set-property Mode ap
iwctl device wlp2s0 set-property Mode station
iwctl device wlp2s0 set-property Mode ap
iwctl ap wlp2s0 start myssid secret123
iwctl ap wlp2s0 show
++++++++ backtrace ++++++++
0 0x7f8f1a8fe320 in /lib64/libc.so.6
1 0x451f35 in ap_dbus_get_diagnostics() at src/ap.c:4043
2 0x4cdf5a in _dbus_object_tree_dispatch() at ell/dbus-service.c:1815
3 0x4bffc7 in message_read_handler() at ell/dbus.c:285
4 0x4b5d7b in io_callback() at ell/io.c:120
5 0x4b489b in l_main_iterate() at ell/main.c:476
6 0x4b49a6 in l_main_run() at ell/main.c:519
7 0x4b4cd9 in l_main_run_with_signal() at ell/main.c:645
8 0x404f5b in main() at src/main.c:600
9 0x7f8f1a8e8b75 in /lib64/libc.so.6
+++++++++++++++++++++++++++
Scanning while in AP mode is somewhat of an edge case, but it does
have some usefulness specifically with onboarding new devices, i.e.
a new device starts an AP, a station connects and provides the new
device with network credentials, the new device switches to station
mode and connects to the desired network.
In addition this could be used later for ACS (though this is a bit
overkill for IWD's access point needs).
Since AP performance is basically non-existant while scanning this
feature is meant to be used in a limited scope.
Two DBus API's were added which mirror the station interface: Scan and
GetOrderedNetworks.
Scan is no different than the station variant, and will perform an active
scan on all channels.
GetOrderedNetworks diverges from station and simply returns an array of
dictionaries containing basic information about networks:
{
Name: <ssid>
SignalStrength: <mBm>
Security: <psk, open, or 8021x>
}
Limitations:
- Hidden networks are not supported. This isn't really possible since
the SSID's are unknown from the AP perspective.
- Sharing scan results with station is not supported. This would be a
convenient improvement in the future with respect to onboarding new
devices. The scan could be performed in AP mode, then switch to
station and connect immediately without needing to rescan. A quick
hack could better this situation by not flushing scan results in
station (if the kernel retains these on an iftype change).
Previously we added logic to defer doing anything in ap_free() to after
the AP event handler has returned so that ap_event() has a chance to
inform whoever called it that the ap_state has been freed. But there's
also a chance that the event handler is destroying both the AP and the
netdev it runs on, so after the handler has returned we can't even use
netdev_get_wdev_id or netdev_get_ifindex. The easiest solution seems to
be to call ap_reset() in ap_free() even if we're within an event handler
to ensure we no longer need any external objects. Also make sure
ap_reset() can be called multiple times.
Another option would be to watch for NETDEV_WATCH_EVENT_DEL and remove
our reference to the netdev (because there's no need actually call
l_rtnl_ifaddr_delete or frame_watch_wdev_remove if the netdev was
destroyed -- frame_watch already tracks netdev removals), or to save
just the ifindex and the wdev id...
ap.c has been mostly careful to call the event handler at the end of any
externally called function to allow methods like ap_free() to be called
within the handler, but that isn't enough. For example in
ap_del_station we may end up emitting two events: STATION_REMOVED and
DHCP_LEASE_EXPIRED. Use a slightly more complicated mechanism to
explicitly guard ap_free calls inside the event handler.
To make it easier, simplify cleanup in ap_assoc_reassoc with the use of
_auto_.
In ap_del_station reorder the actions to send the STATION_REMOVED event
first as the DHCP_LEASE_EXPIRED is a consequence of the former and it
makes sense for the handler to react to it first.
Add netconfig_enabled() and use that in all places that want to know
whether network configuration is enabled. Drop the enable_network_config
deprecated setting, which was only being handled in one of these 5 or so
places.
Handle the 802.11ai FILS IP Address Assignment IEs in Association
Request frames when netconfig is enabled. Only IPv4 is supported.
Like the P2P IP Allocation mechanism, since the payload format and logic
is independent from the rest of the FILS standard this is enabled
unconditionally for clients who want to use it even though we don't
actually do FILS in AP mode.
If netconfig is enabled tell the DHCP server to expire any leases owned
by the client that is disconnecting by using l_dhcp_server_expire_by_mac
to return the IPs to the IP pool. They're added to the expired list
so they'd only be used if there are no other addresses left in the pool
and can be reactivated if the client comes back before the address is
used by somebody else.
This should ensure that we're always able to offer an address to a new
client as long as there are fewer concurrent clients than addresses in
the configured subnet or IP range.
Use the struct handshake_state::support_ip_allocation field already
supported in eapol.c authenticator side to enable the P2P IP Allocation
mechanism in ap.c. Add the P2P_GROUP_CAP_IP_ALLOCATION bit in P2P group
capabilities to signal the feature is now supported.
There's no harm in enabling this feature in every AP (not just P2P Group
Owner) but the clients won't know whether we support it other than
through that P2P-specific group capability bit.
Replace instances of the ap_del_station() +
ap_sta_free()/ap_remove_sta() with calls to ap_station_disconnect to
make sure we consistently remove the station from the ap->sta_states
queue before using ap_del_station(). ap_del_station() may generate an
event to the ap.h API user (e.g. P2P) and this may end up tearing down
the AP completely.
For that scenario we also don't want ap_sta_free() to access sta->ap so
we make sure ap_del_station() performs these cleanup steps so that
ap_sta_free() has nothing to do that accesses sta->ap.
client_frame is not valid for a beacon frame as beacons are not sent in
response to another frame. Move the access to client_frame->address_2
to the conditional blocks for Probe Response and Association Response
frames.
ie_tlv_builder_init takes a size_t as input, yet for some reason
ie_tlv_builder_finalize takes an unsigned int argument as output. Fix
the latter to use size_t as well.
