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which ends up crashing since the AP interface objects are no longer
valid.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.
Change the char *addr_str and uint8_t prefix_len pair to an
l_rtnl_address object and use ell/rtnl.h utilities that use that
directly. Extend broadcast_from_ip to handle prefix_len.
We generate the DBus error reply type from the errno only when
ap_start() was failing synchronously, now also send the errno through
the callbacks so that we can also return a specific DBus reply when
failing asynchronously. Thea AP autotest relies on receiving the
AlreadyExists DBus error.
Deprecate the global [General].APRanges setting in favour of
[IPv4].APAddressPool with an extended (but backwards-compatible) syntax.
Drop the existing address pool creation code.
The new APAddressPool setting has the same syntax as the profile-local
[IPv4].Address setting and the subnet selection code will fall back
to the global setting if it's missing, this way we use common code to
handle both settings.
Extend the [IPv4].Address setting's syntax to allow a new format: a list
of <IP>/<prefix_len> -form strings that define the address space from
which a subnet is selected. Rewrite the DHCP settings loading with
other notable changes:
* validate some of the settings more thoroughly,
* name all netconfig-related ap_state members with the netconfig_
prefix,
* make sure we always call l_dhcp_server_set_netmask(),
* allow netmasks other than 24-bit and change the default to 28 bits,
* as requested avoid using the l_net_ ioctl-based functions although
l_dhcp still uses them internally,
* as requested avoid touching the ap_state members until the end of
some functions so that on error they're basically a no-op (for
readability).
ap_reset() seems to be called whenever the AP is stopped or removed due
to interface shutdown. For some reason ap_reset did not remove the DHCP
server object, resulting in leaks:
==211== at 0x483879F: malloc (vg_replace_malloc.c:307)
==211== by 0x46B5AD: l_malloc (util.c:62)
==211== by 0x49B0E2: l_dhcp_server_new (dhcp-server.c:715)
==211== by 0x433AA3: ap_setup_dhcp (ap.c:2615)
==211== by 0x433AA3: ap_load_dhcp (ap.c:2645)
==211== by 0x433AA3: ap_load_config (ap.c:2753)
==211== by 0x433AA3: ap_start (ap.c:2885)
==211== by 0x434A96: ap_dbus_start_profile (ap.c:3329)
==211== by 0x482DA9: _dbus_object_tree_dispatch (dbus-service.c:1815)
==211== by 0x47A4D9: message_read_handler (dbus.c:285)
==211== by 0x4720EB: io_callback (io.c:120)
==211== by 0x47130C: l_main_iterate (main.c:478)
==211== by 0x4713DB: l_main_run (main.c:525)
==211== by 0x4713DB: l_main_run (main.c:507)
==211== by 0x4715EB: l_main_run_with_signal (main.c:647)
==211== by 0x403EE1: main (main.c:550)
Previously resp was a simple array of bytes allocated on the stack.
This was changed to a dynamically allocated array, but the sizeof(resp)
argument to ap_build_beacon_pr_head() was never changed appropriately.
Fix this by introducing a new resp_len variable that holds the number of
bytes allocated for resp. Also, move the allocation after the basic
sanity checks have been performed to avoid allocating/freeing memory
unnecessarily.
Fixes: 18a63f91fd ("ap: Write extra frame IEs from the user")
Prior to this netdev_connect_ok set setting this which really
only applies to station mode. In addition this happens for each
new station that connects to the AP. Instead set the operstate /
link mode when AP starts and stops.
Change ap_start to load all of the AP configuration from a struct
l_settings, moving the 6 or so parameters from struct ap_config members
to the l_settings groups and keys. This extends the ap profile concept
used for the DHCP settings. ap_start callers create the l_settings
object and fill the values in it or read the settings in from a file.
Since ap_setup_dhcp and ap_load_profile_and_dhcp no longer do the
settings file loading, they needed to be refactored and some issues were
fixed in their logic, e.g. l_dhcp_server_set_ip_address() was never
called when the "IP pool" was used. Also the IP pool was previously only
used if the ap->config->profile was NULL and this didn't match what the
docs said:
"If [IPv4].Address is not provided and no IP address is set on the
interface prior to calling StartProfile the IP pool will be used."
It was seen that some full mac cards/drivers do not include any
rate information with the NEW_STATION event. This was causing
the NEW_STATION event to be ignored, preventing AP mode from
working on these cards.
Since the full mac path does not even require sta->rates the
parsing can be removed completely.
Make the WSC IE processing and writing more self-contained (i.e. so that
it can be more easily moved to a separate file if desired) by using the
new ap_write_extra_ies() mechanism.
Pass the string IEs from the incoming STA association frames to
the user in the AP event data. I drop
ap_event_station_added_data.rsn_ie because that probably wasn't
going to ever be useful and the RSN IE is included in the .assoc_ies
array in any case.
James Prestwood