If the connected BSS changes channel, netdev will emit an event with the
new channel's frequency. In response, have station change the frequency
of the connected scan_bss struct and inform network about the update.
If the connected BSS announces that it is switching operating channel,
the kernel may emit the NL80211_CMD_CH_SWTICH_NOTIFY event when the
switch is complete. Add a new netdev event NETDEV_EVENT_CHANNEL_SWITCHED
to signal to interested modules that the connected BSS has changed
channel. The event carries a pointer to the new channel's frequency.
NL80211_BSS_LAST_SEEN_BOOTTIME is expressed in nanoseconds, while BSS
timestamps are expressed in microseconds internally. Convert the
attribute to microseconds when using it to timestamp a BSS. This makes
iwd expire absent BSSes within 30 seconds as intended.
Fixes: 454cee12d4 ("scan: Use kernel-reported time-stamp if provided")
Right now, if a connection to a network selected by auto-connect fails,
the entire autoconnect process is restarted. This means that scans are
kicked off again, auto-connect list is rebuilt, etc. This was due to
auto-connect reusing the same failure path as connections triggered via
D-Bus.
The above behavior can lead to weird situations in certain corner cases.
For example, a highly preferred network configured with the wrong
password would result in auto-connect entering an infinite loop.
Fix this by making sure that all auto-connect entries are tried and
exhausted prior to re-scanning again.
The temporary ban list is cleared when a network is connected to
successfully, and also in network_connect_failed. Unfortunately,
network_connect_failed is not called in all paths (i.e. during
autoconnect) since it messes with the state of secrets and passphrases.
Clear the list in network_disconnected() instead, since it is guaranteed
to be called in every circumstance.
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.
Code that walked the VHT TX/RX MCS maps seemed to assume that bit_field
operated on bits that start at '1'. But this utility actually operates
on bits that start at '0'. I.e. the least significant bit is at
position 0.
While we're at it, rename the mcs variable into bitoffset to make it
clearer how the maps are being iterated over. Supported MCS is actually
the value found in the map.
This option has not been used in a very long time, and is of limited
utility since the only thing D-Bus debugging does is hexdumps the
content of D-Bus messages to the terminal.
The current calculation was giving erroneous results when it came to VHT
MCS index 4 and VHT MCS index 8 & 9.
Switch to a precomputed look up table and add a multiplication factor
for short GI.
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)
==209== by 0x43E48A: netconfig_ipv4_select_and_install (netconfig.c:887)
==209== by 0x43E48A: netconfig_configure (netconfig.c:1025)
==209== by 0x41743C: station_connect_cb (station.c:2556)
==209== by 0x408E0D: netdev_connect_ok (netdev.c:1311)
==209== by 0x47549E: process_unicast (genl.c:994)
==209== by 0x47549E: received_data (genl.c:1102)
==209== by 0x4720EB: io_callback (io.c:120)
==209== by 0x47130C: l_main_iterate (main.c:478)
==209== by 0x4713DB: l_main_run (main.c:525)
==209== by 0x4713DB: l_main_run (main.c:507)
==209== by 0x4715EB: l_main_run_with_signal (main.c:647)
==209== by 0x403EE1: main (main.c:550)
Prior to the BSS blacklist a BSS based autoconnect list made
the most sense, but now station actually retries all BSS's upon
failure. This means that for each BSS in the autoconnect list
every other BSS under that SSID will be attempted to connect to
if there is a failure. Essentially this is a network based
autoconnect list, just an indirect way of doing it.
Intead the autoconnect list can be purely network based, using
the network rank for sorting. This avoids the need for a special
autoconnect_entry struct as well as ensures the last connected
network is chosen first (simply based on existing network ranking
logic).
It was observed that IWD's ranking for BSS's did not always
end up with the fastest being chosen. This was due to IWD's
heavy weight on signal strength. This is a decent way of ranking
but even better is calculating a theoretical data rate which
was also done and factored in. The problem is the data rate
factor was always outdone by the signal strength.
Intead remove signal strength entirely as this is already taken
into account with the data rate calculation. This also removes
the check for rate IEs. If no IEs are found the parser will
base the data rate soley on RSSI.
There were a few other factors removed which will be added back
when ranking *networks* rather than BSS's. WPA version (or open)
was removed as well as the privacy capability. These values really
should not differ between BSS's in the same SSID and as such
should be used for network ranking instead.
Both ext/supported rates IEs are obtained from scan results. These
IEs are passed to ie_tlv_init/ie_tlv_next, as well as direct length
checks (for supported rates at least, extended supported rates can
be as long as a single byte integer can hold, 1 - 255) which verifies
that the length in the IE matches the overall IE length that is
stored in scan_bss. Because of this, ie_parse_supported_rates_from_data
was doing double duty re-initializing a TLV iterator.
Intead, since we know the IE length is within bounds, the length/data
can simply be directly accessed out of the buffer. This avoids the need
for a wrapper function entirely.
The length parameters were also removed, since this is now obtained
directly from the IE.
Since netdev maintains the list of FT over DS info structs there is not
any need for station to get callbacks when the initial action frame
is received, or not. This removes the need for the callback handler,
user data, and response timeout.
Roam times can be slightly improved by sending out the FT-over-DS
action frames to any BSS in the mobility domain immediately after
connecting. This preauthenticates IWD to each AP which means
Reassociation can happen right away when a roam is needed.
When a roam is needed station_transition_start will first try
FT-over-DS (if supported) via netdev_fast_transtion_over_ds. The
return is checked and if netdev has no cached entries FT-over-Air
will be used instead.
The beauty of FT-over-DS is that a station can send and receive
action frames to many APs to prepare for a future roam. Each
AP authenticates the station and when a roam happens the station
can immediately move to reassociation.
To handle this a queue of netdev_ft_over_ds_info structs is used
instead of a single entry. Using the new ft.c parser APIs these
info structs can be looked up when responses come in. For now
the timeouts/callbacks are kept but these will be removed as it
really does not matter if the AP sends a response (keeps station
happy until the next patch).
This is to prepare for multiple concurrent FT-over-DS action frames.
A list will be kept in netdev and for lookup reasons it needs to
parse the start of the frame to grab the aa/spa addresses. In this
call the IEs are also returned and passed to the new
ft_over_ds_parse_action_response.
For now the address checks have been moved into netdev, but this will
eventually turn into a queue lookup.
This value sets the roaming threshold on 5GHz networks. The
threshold has been separated from 2.4GHz because in many cases
5GHz can perform much better at low RSSI than 2.4GHz.
In addition the BSS ranking logic was re-worked and now 5GHz is
much more preferred, even at low RSSI. This means we need a
lower floor for RSSI before roaming, otherwise IWD would end
up roaming immediately after connecting due to low RSSI CQM
events.
This is being added as a developer method and should not be used
in production. For testing purposes though, it is quite useful as
it forces IWD to roam to a provided BSS and bypasses IWD's roaming
and ranking logic for choosing a roam candidate.
To use this a BSSID is provided as the only parameter. If this
BSS is not in IWD's current scan results -EINVAL will be returned.
If IWD knows about the BSS it will attempt to roam to it whether
that is via FT, FT-over-DS, or Reassociation. These details are
still sorted out in IWDs station_transition_start() logic.
This will enable developer features to be used. Currently the
only user of this will be StationDiagnostics.Roam() method which
should only be exposed in this mode.
Expose the state directory/storage directory path on D-Bus because it
can't be known to clients until IWD runs, and client might need to
occasionally fiddle with the network config files. While there also
expose the IWD version string, similar to how some other D-Bus services
do.
Similar to 06aa84cca set the operstate when AdHoc is started and
stopped as it is no longer always set by netdev (only for station/p2p
interface types)
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")
Commit 1fe5070 added a workaround for drivers which may send the
connect event prior to the connect callback/ack. This caused IWD
to fail to start eapol if reassociation was used due to
netdev_reassociate never setting netdev->connected = false.
netdev_reassociate uses the same code path as normal connections,
but when the connect callback came in connected was already set
to true which then prevents eapol from being registered. Then,
once the connect event comes in, there is no frame watch for
eapol and IWD doesn't respond to any handshake frames.
Prior to this, an error sending the FT Reassociation was treated
as fatal, which is correct for FT-over-Air but not for FT-over-DS.
If the actual l_genl_family_send call fails for FT-over-DS the
existing connection can be maintained and there is no need to
call netdev_connect_failed.
Adding a return to the tx_associate function works for both FT
types. In the FT-over-Air case this return will ultimately get
sent back up to auth_proto_rx_authenticate in which case will
call netdev_connect_failed. For FT-over-DS tx_associate is
actually called from the 'start' operation which can fail and
still maintain the existing connection.
FT-over-DS was refactored to separate the FT action frame and
reassociation. From stations standpoint IWD needs to call
netdev_fast_transition_over_ds_action prior to actually roaming.
For now these two stages are being combined and the action
roam happens immediately after the action response callback.
FT-over-DS followed the same pattern as FT-over-Air which worked,
but really limited how the protocol could be used. FT-over-DS is
unique in that we can authenticate to many APs by sending out
FT action frames and parsing the results. Once parsed IWD can
immediately Reassociate, or do so at a later time.
To take advantage of this IWD need to separate FT-over-DS into
two stages: action frame and reassociation.
The initial action frame stage is started by netdev. The target
BSS is sent an FT action frame and a new cache entry is created
in ft.c. Once the response is received the entry is updated
with all the needed data to Reassociate. To limit the record
keeping on netdev each FT-over-DS entry holds a userdata pointer
so netdev doesn't need to maintain its own list of data for
callbacks.
Once the action response is parsed netdev will call back signalling
the action frame sequence was completed (either successfully or not).
At this point the 'normal' FT procedure can start using the
FT-over-DS auth-proto.
Alvin Šipraga