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).
A new API was added, ft_authenticate, which will send an
authentication frame offchannel via CMD_FRAME. This bypasses
the kernel's authentication state allowing multiple auth
attempts to take place without disconnecting.
Currently netdev handles caching FT auth information and uses FT
parsers/auth-proto to manage the protocol. This sets up to remove
this state machine from netdev and isolate it into ft.c.
This does not break the existing auth-proto (hence the slight
modifications, which will be removed soon).
Eventually the auth-proto will be removed from FT entirely, replaced
just by an FT state machine, similar to how EAPoL works (netdev hooks
to TX/RX frames).
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.
The warnings in the authenticate and connect events were identical
so it could be difficult knowing which print it was if IWD is not
in debug mode (to see more context). The prints were changed to
indicate which event it was and for the connect event the reason
attribute is also parsed.
Note the resp_ies_len is also initialized to zero now. After making
the changes gcc was throwing a warning.
FT is special in that it really should not be interrupted. Since
FRAME/OFFCHANNEL have the highest priority we run the risk of
DPP or some other offchannel operation interfering with FT.
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.
Since l_netconfig's DHCPv6 client instance no longer sets parameters on
the l_icmp6_client instance, call l_icmp6_client_set_nodelay() and
l_icmp6_client_set_debug() directly. Also enable optimistic DAD to
speed up IPv6 setup if available.
All uses of frame-xchg were for action frames, and the frame type
was hard coded. Soon other frame types will be needed so the type
must now be specified in the frame_xchg_prefix structure.
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.
Add a second netconfig-commit backend which, if enabled, doesn't
directly send any of the network configuration to the kernel or system
files but delegates the operation to an interested client's D-Bus
method as described in doc/agent-api.txt. This backend is switched to
when a client registers a netconfig agent object and is swiched away
from when the client disconnects or unregisters the agent. Only one
netconfig agent can be registered any given time.
Add netconfig_event_handler() that responds to events emitted by
the l_netconfig object by calling netconfig_commit, tracking whether
we're connected for either address family and emitting
NETCONFIG_EVENT_CONNECTED or NETCONFIG_EVENT_FAILED as necessary.
NETCONFIG_EVENT_FAILED is a new event as until now failures would cause
the netconfig state machine to stop but no event emitted so that
station.c could take action. As before, these events are only
emitted based on the IPv4 configuration state, not IPv6.
Add netconfig-commit.c whose main method, netconfig_commit actually sets
the configuration obtained by l_netconfig to the system netdev,
specifically it sets local addresses on the interface, adds routes to the
routing table, sets DNS related data and may add entries to the neighbor
cache. netconfig-commit.c uses a backend-ops type structure to allow
for switching backends. In this commit there's only a default backend
that uses l_netconfig_rtnl_apply() and a struct resolve object to write
the configuration.
netconfig_gateway_to_arp is moved from netconfig.c to netconfig-commit.c
(and renamed.) The struct netconfig definition is moved to netconfig.h
so that both files can access the settings stored in the struct.
To avoid repeated lookups by ifindex, replace the ifindex member in
struct netconfig with a struct netdev pointer. A struct netconfig
always lives shorter than the struct netdev.
* make the error handling simpler,
* make error messages more consistent,
* validate address families,
* for IPv4 skip l_rtnl_address_set_noprefixroute()
as l_netconfig will do this internally as needed.
* for IPv6 set the default prefix length to 64 as that's going to be
used for the local prefix route's prefix length and is a more
practical value.
Drop all the struct netconfig members where we were keeping the parsed
netconfig settings and add a struct l_netconfig object. In
netconfig_load_settings load all of the settings once parsed directly
into the l_netconfig object. Only preserve the mdns configuration and
save some boolean values needed to properly handle static configuration
and FILS. Update functions to use the new set of struct netconfig
members.
These booleans mirroring the l_netconfig state could be replaced by
adding l_netconfig getters for settings which currently only have
setters.
In anticipation of switching to use the l_netconfig API, which
internally handles DHCPv4, DHCPv6, ACD, etc., drop pointers to
instances of l_dhcp_client, l_dhcp6_client and l_acd from struct
netconfig. Also drop all code used for handling events from these
APIs, including code to commit the received configurations to the
system. Committing the final settings to the system netdevs is going to
be handled by a new set of utilities in a new file.
The RRM module was blindly scanning using the requested
frequency which may or may not be possible given the hardware.
Instead check that the frequency will work and if not reject
the request.
This was reported by a user seeing the RRM scan fail which was
due to the AP requesting a scan on 5GHz when the adapter was
2.4GHz only.
Support for MAC address changes while powered was recently added to
mac80211. This avoids the need to power down the device which both
saves time as well as preserves any allowed frequencies which may
have been disabled if the device powered down.
The code path for changing the address was reused but now just the
'up' callback will be provided directly to l_rtnl_set_mac. Since
there aren't multiple stages of callbacks the rtnl_data structure
isn't strictly needed, but the code looks cleaner and more
consistent between the powered/non-powered code paths.
The comment/debug error print was also updated to be more general
between the two MAC change code paths.
Documentation for MulticastDNS setting suggests it should be part of the
main iwd configuration file. See man iwd.config. However, in reality
the setting was being pulled from the network provisioning file instead.
The latter actually makes more sense since systemd-resolved has its own
set of global defaults. Fix the documentation to reflect the actual
implementation.
netdev does not keep any pointers to struct scan_bss arguments that are
passed in. Make this explicitly clear by modifying the API definitions
and mark these as const.
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.
If a OWE network is buggy and requires the default group this info
needs to be stored in network in order for it to set this into the
handshake on future connect attempts.
This functionality works around the kernel's behavior of allowing
6GHz only after a regulatory domain update. If the regdom updates
scan.c needs to be aware in order to split up periodic scans, or
insert 6GHz frequencies into an ongoing periodic scan. Doing this
allows any 6GHz BSS's to show up in the scan results rather than
needing to issue an entirely new scan to see these BSS's.
The kernel's regulatory domain updates after some number of beacons
are processed. This triggers a regulatory domain update (and wiphy
dump) but only after a scan request. This means a full scan started
prior to the regdom being set will not include any 6Ghz BSS's even
if the regdom was unlocked during the scan.
This can be worked around by splitting up a large scan request into
multiple requests allowing one of the first commands to trigger a
regdom update. Once the regdom updates (and wiphy dumps) we are
hopefully still scanning and could append an additional request to
scan 6GHz.
In the case of an external scan, we won't have a scan_request object,
sr. Make sure to not crash in this case.
Also, since scan_request can no longer carry the frequency set in all
cases, add a new member to scan_results in order to do so.
Fixes: 27d8cf4ccc59 ("scan: track scanned frequencies for entire request")
