If IWD gets a disconnect during FT the roaming state will be
cleared, as well as any ft_info's during ft_clear_authentications.
This includes canceling the offchannel operation which also
destroys any pending ft_info's if !info->parsed. This causes a
double free afterwards. In addition the l_queue_remove inside the
foreach callback is not a safe operation either.
To fix this don't remove the ft_info inside the offchannel
destroy callback. The info will get freed by ft_associate regardless
of the outcome (parsed or !parsed). This is also consistent with
how the onchannel logic works.
Log and crash backtrace below:
iwd[488]: src/station.c:station_try_next_transition() 5, target aa:46:8d:37:7c:87
iwd[488]: src/wiphy.c:wiphy_radio_work_insert() Inserting work item 16668
iwd[488]: src/wiphy.c:wiphy_radio_work_insert() Inserting work item 16669
iwd[488]: src/wiphy.c:wiphy_radio_work_done() Work item 16667 done
iwd[488]: src/wiphy.c:wiphy_radio_work_next() Starting work item 16668
iwd[488]: src/netdev.c:netdev_mlme_notify() MLME notification Remain on Channel(55)
iwd[488]: src/netdev.c:netdev_mlme_notify() MLME notification Del Station(20)
iwd[488]: src/netdev.c:netdev_link_notify() event 16 on ifindex 5
iwd[488]: src/netdev.c:netdev_mlme_notify() MLME notification Deauthenticate(39)
iwd[488]: src/netdev.c:netdev_deauthenticate_event()
iwd[488]: src/netdev.c:netdev_mlme_notify() MLME notification Disconnect(48)
iwd[488]: src/netdev.c:netdev_disconnect_event()
iwd[488]: Received Deauthentication event, reason: 6, from_ap: true
iwd[488]: src/station.c:station_disconnect_event() 5
iwd[488]: src/station.c:station_disassociated() 5
iwd[488]: src/station.c:station_reset_connection_state() 5
iwd[488]: src/station.c:station_roam_state_clear() 5
iwd[488]: double free or corruption (fasttop)
5 0x0000555b3dbf44a4 in ft_info_destroy ()
6 0x0000555b3dbf45b3 in remove_ifindex ()
7 0x0000555b3dc4653c in l_queue_foreach_remove ()
8 0x0000555b3dbd0dd1 in station_reset_connection_state ()
9 0x0000555b3dbd37e5 in station_disassociated ()
10 0x0000555b3dbc8bb8 in netdev_mlme_notify ()
11 0x0000555b3dc4e80b in received_data ()
12 0x0000555b3dc4b430 in io_callback ()
13 0x0000555b3dc4a5ed in l_main_iterate ()
14 0x0000555b3dc4a6bc in l_main_run ()
15 0x0000555b3dc4a8e0 in l_main_run_with_signal ()
16 0x0000555b3dbbe888 in main ()
Hostapd commit bc36991791 now properly sets the secure bit on
message 1/4. This was addressed in an earlier IWD commit but
neglected to allow for backwards compatibility. The check is
fatal which now breaks earlier hostapd version (older than 2.10).
Instead warn on this condition rather than reject the rekey.
Fixes: 7fad6590bd ("eapol: allow 'secure' to be set on rekeys")
The HT40+/- flags were reversed when checking against the 802.11
behavior flags.
HT40+ means the secondary channel is above (+) the primary channel
therefore corresponds to the PRIMARY_CHANNEL_LOWER behavior. And
the opposite for HT40-.
Reported-By: Alagu Sankar <alagusankar@gmail.com>
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.
Currently when we try FT-over-Air, the Authenticate frame is always
sent via offchannel infrastructure We request the driver to go
offchannel, then send the Authenticate frame. This works fine as long
as the target AP is on a different channel. On some networks some (or
all) APs might actually be located on the same channel. In this case
going offchannel will result in some drivers not actually sending the
Authenticate frame until after the offchannel operation completes.
Work around this by introducing a new ft_authenticate variant that will
not request an offchannel operation first.
Force conversion to unsigned char before printing to avoid sign
extension when printing SSID in hex. For example, if there are CJK
characters in SSID, it will generate a very long string like
/net/connman/iwd/ffffffe8ffffffaeffffffa1.
If a very long ssid was used (e.g. CJK characters in SSID), it might do
out of bounds write to static variable for lack of checking the position
before the last snprintf() call.
Seeing that some authenticators can't handle TLS session caching
properly, allow the EAP-TLS-based methods session caching support to be
disabled per-network using a method specific FastReauthentication setting.
Defaults to true.
With the previous commit, authentication should succeed at least every
other attempt. I'd also expect that EAP-TLS is not usually affected
because there's no phase2, unlike with EAP-PEAP/EAP-TTLS.
If we have a TLS session cached from this attempt or a previous
successful connection attempt but the overall EAP method fails, forget
the session to improve the chances that authentication succeeds on the
next attempt considering that some authenticators strangely allow
resumption but can't handle it all the way to EAP method success.
Logically the session resumption in the TLS layers on the server should
be transparent to the EAP layers so I guess those may be failed
attempts to further optimise phase 2 when the server thinks it can
already trust the client.
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.
Since channels numbers are used as indexes into the array, and given
that channel numbers start at '1' instead of 0, make sure to allocate a
buffer large enough to not overflow when the max channel number for a
given band is accessed.
src/manager.c:manager_wiphy_dump_callback() New wiphy phy1 added (1)
==22290== Invalid write of size 2
==22290== at 0x4624B2: nl80211_parse_supported_frequencies (nl80211util.c:570)
==22290== by 0x417CA5: parse_supported_bands (wiphy.c:1636)
==22290== by 0x418594: wiphy_parse_attributes (wiphy.c:1805)
==22290== by 0x418E20: wiphy_update_from_genl (wiphy.c:1991)
==22290== by 0x464589: manager_wiphy_dump_callback (manager.c:564)
==22290== by 0x4CBDDA: process_unicast (genl.c:944)
==22290== by 0x4CC19C: received_data (genl.c:1056)
==22290== by 0x4C7140: io_callback (io.c:120)
==22290== by 0x4C5A97: l_main_iterate (main.c:476)
==22290== by 0x4C5BDC: l_main_run (main.c:523)
==22290== by 0x4C5F0F: l_main_run_with_signal (main.c:645)
==22290== by 0x40503B: main (main.c:600)
==22290== Address 0x4aa76ec is 0 bytes after a block of size 28 alloc'd
==22290== at 0x48417B5: malloc (vg_replace_malloc.c:393)
==22290== by 0x4BC4D1: l_malloc (util.c:62)
==22290== by 0x417BE4: parse_supported_bands (wiphy.c:1619)
==22290== by 0x418594: wiphy_parse_attributes (wiphy.c:1805)
==22290== by 0x418E20: wiphy_update_from_genl (wiphy.c:1991)
==22290== by 0x464589: manager_wiphy_dump_callback (manager.c:564)
==22290== by 0x4CBDDA: process_unicast (genl.c:944)
==22290== by 0x4CC19C: received_data (genl.c:1056)
==22290== by 0x4C7140: io_callback (io.c:120)
==22290== by 0x4C5A97: l_main_iterate (main.c:476)
==22290== by 0x4C5BDC: l_main_run (main.c:523)
==22290== by 0x4C5F0F: l_main_run_with_signal (main.c:645)
==22290==
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.
The only changes required was to set the secure bit for message 1,
reset the frame retry counter, and change the 2/4 verifier to use
the rekey flag rather than ptk_complete. This is because we must
set ptk_complete false in order to detect retransmissions of the
4/4 frame.
Initiating a rekey can now be done by simply calling eapol_start().
If IWD ends up dumping wiphy's twice (because of NEW_WIPHY event
soon after initial dump) it will also try and dump interfaces
twice leading to multiple DEL_INTERFACE calls. The second attempt
will fail with -ENODEV (since the interface was already deleted).
Just silently fail with this case and let the other DEL_INTERFACE
path handle the re-creation.
With really badly timed events a wiphy can be registered twice. This
happens when IWD starts and requests a wiphy dump. Immediately after
a NEW_WIPHY event comes in (presumably when the driver loads) which
starts another dump. The NEW_WIPHY event can't simply be ignored
since it could be a hotplug (e.g. USB card) so to fix this we can
instead just prevent it from being registered.
This does mean both dumps will happen but the information will just
be added to the same wiphy object.
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]: +++++++++++++++++++++++++++
If the authenticator has already set an snonce then the packet must
be a retransmit. Handle this by sending 3/4 again but making sure
to not reset the frame counter.
Old wpa_supplicant versions do not set the secure bit on 2/4 during
rekeys which causes IWD to reject the message and eventually time out.
Modern versions do set it correctly but even Android 13 (Pixel 5a)
still uses an ancient version of wpa_supplicant which does not set the
bit.
Relax this check and instead just print a warning but allow the message
to be processed.
In try_handshake_complete() we return early if all the keys had
been installed before (initial associations). For rekeys we can
now emit the REKEY_COMPLETE event which lets AP mode reset the
rekey timer for that station.
When the TK is installed the 'ptk_installed' flag was never set to
zero. For initial associations this was fine (already zero) but for
rekeys the flag needs to be unset so try_handshake_complete knows
if the key was installed. This is consistent with how gtk/igtk keys
work as well.
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.
The second handshake message was hard coded with the secure bit as
zero but for rekeys the secure bit should be set to 1. Fix this by
changing the 2/4 builder to take a boolean which will set the bit
properly.
It should be noted that hostapd doesn't check this bit so EAPoL
worked just fine, but IWD's checks are more strict.
The PEAP RFC wants implementations to enforce that Phase2 methods have
been successfully completed prior to accepting a successful result TLV.
However, when TLS session resumption is used, some servers will skip
phase2 methods entirely and simply send a Result TLV with a success
code. This results in iwd (erroneously) rejecting the authentication
attempt.
Fix this by marking phase2 method as successful if session resumption is
being used.
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.
IWD's channel/frequency conversions use simple math to convert and
have very minimal checks to ensure the input is valid. This can
lead to some channels/frequencies being calculated which are not
in IWD's E-4 table, specifically in the 5GHz band.
This is especially noticable using mac80211_hwsim which includes
some obscure high 5ghz frequencies which are not part of the 802.11
spec.
To fix this calculate the frequency or channel then iterate E-4
operating classes to check that the value actually matches a class.
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.
For AP mode its convenient for IWD to choose an appropriate
channel definition rather than require the user provide very
low level parameters such as channel width, center1 frequency
etc. For now only HT is supported as VHT/HE etc. require
additional secondary channel frequencies.
The HT API tries to find an operating class using 40Mhz which
complies with any hardware restrictions. If an operating class is
found that is supported/not restricted it is marked as 'best' until
a better one is found. In this case 'better' is a larger channel
width. Since this is HT only 20mhz and 40mhz widths are checked.
This adds some additional parsing to obtain the AMPDU parameter
byte as well as wiphy_get_ht_capabilities() which returns the
complete IE (combining the 3 separate kernel attributes).
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.
Move the l_netconfig_set_route_priority() and
l_netconfig_set_optimistic_dad_enabled() calls from netconfig_new, which
is called once for the l_netconfig object's lifetime, to
netconfig_load_settings, which is called before every connection attempt.
This is needed because we clean up the l_netconfig configuration by calling
l_netconfig_reset_config() at different points in connection setup and
teardown so we'd reset the route priority that we've set in netconfig_new,
back to 0 and never reload it.
The disabled_freqs list is being removed and replaced with a new
list in the band object. This completely removes the need for
the pending_freqs list as well since any regdom related dumps
can just overwrite the existing frequency list.
This adds two new APIs:
wiphy_get_frequency_info(): Used to get information about a given
frequency such as disabled/no-IR. This can also be used to check
if the frequency is supported (NULL return is unsupported).
wiphy_band_is_disabled(): Checks if a band is disabled. Note that
an unsupported band will also return true. Checking support should
be done with wiphy_get_supported_bands()
As additional frequency info is needed it doesn't make sense to
store a full list of frequencies for every attribute (i.e.
supported, disabled, no-IR, etc).
This changes nl80211_parse_supported_frequencies to take a list
of frequency attributes where each index corresponds to a channel,
and each value can be filled with flag bits to signal any
limitations on that frequency.
wiphy.c then had to be updated to use this rather than the existing
scan_freq_set lists. This, as-is, will break anything using
wiphy_get_disabled_freqs().
Currently the wiphy object keeps track of supported and disabled
frequencies as two separate scan_freq_set's. This is very expensive
and limiting since we have to add more sets in order to track
additional frequency flags (no-IR, no-HT, no-HE etc).
Instead we can refactor how frequencies are stored. They will now
be part of the band object and stored as a list of flag structures
where each index corresponds to a channel
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.
Queue the FT action just like we do with FT Authenticate which makes
it able to be used the same way, i.e. call ft_action() then queue
the ft_associate work right away.
A timer was added to end the work item in case the target never
responds.
If the regdom updates during a periodic scan the results will be
delayed until after the update in order to, potentially, add 6GHz
frequencies since they may become available. The delayed results
happen regardless of 6GHz support but scan_wiphy_watch() was
returning early if 6GHz was not supported causing the scan request
to never complete.
The blamed commit argues that the periodic scan callback doesn't do
anything useful in the event of an aborted scan, but this is not
entirely true. In particular, the callback is responsible for re-arming
the periodic scan timer. Make sure to call scan_finished() so that iwd's
periodic scanning logic continues unabated even when a periodic scan is
aborted.
Also remove the periodic boolean member of struct scan_request, as it
serves no purpose anymore.
Fixes: 6051a14952 ("scan: Don't callback on SCAN_ABORTED")
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.
wiphy_get_supported_rates expected an enum defined in the nl80211
header but the argument type was an unsigned int, not exactly
intuitive to anyone using the API. Since the nl80211 enum value
was only used in a switch statement it could just as well be IWD's
internal enum band_freq.
This also allows modules which do not reference nl80211.h to use
wiphy_get_supported_rates().
If a CMD_TRIGGER_SCAN request fails with -EBUSY, iwd currently assumes
that a scan is ongoing on the underlying wdev and will retry the same
command when that scan is complete. It gets notified of that completion
via the scan_notify() function, and kicks the scan logic to try again.
However, if there is another wdev on the same wiphy and that wdev has a
scan request in flight, the kernel will also return -EBUSY. In other
words, only one scan request per wiphy is permitted.
As an example, the brcmfmac driver can create an AP interface on the
same wiphy as the default station interface, and scans can be triggered
on that AP interface.
If -EBUSY is returned because another wdev is scanning, then iwd won't
know when it can retry the original trigger request because the relevant
netlink event will arrive on a different wdev. Indeed, if no scan
context exists for that other wdev, then scan_notify will return early
and the scan logic will stall indefinitely.
Instead, and in the event that no scan context matches, use it as a cue
to retry a pending scan request that happens to be destined for the same
wiphy.
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.
Use l_tls_set_session_cache() to enable session cache/resume in the
TLS-based EAP methods. Sessions for all 802.1x networks are stored in
one l_settings object.
eap_{get,set}_peer_id() API is added for the upper layers to set the
identifier of the authenticator (or the supplicant if we're the
authenticator, if there's ever a use case for that.)
eap-tls-common.c can't call storage_eap_tls_cache_{load,sync}()
or known_networks_watch_add() (to handle known network removals) because
it's linked into some executables that don't have storage.o,
knownnetworks.o or common.o so an upper layer (station.c) will call
eap_tls_set_session_cache_ops() and eap_tls_forget_peer() as needed.
Minor changes to these two methods resulting from two rewrites of them.
Actual changes are:
* storage_tls_session_sync parameter is const,
* more specific naming,
* storage_tls_session_load will return an empty l_settings instead of
NULL so eap-tls-common.c doesn't have to handle this.
storage.c makes no assumptions about the group names in the l_settings
object and keeps no reference to that object, eap-tls-common.c is going
to maintain the memory copy of the cache since this cache and the disk
copy of it are reserved for EAP methods only.
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.
Adds the MulticastDNS option globally to main.conf. If set all
network connections (when netconfig is enabled) will set mDNS
support into the resolver. Note that an individual network profile
can still override the global value if it sets MulticastDNS.
The limitation of cipher selection in ap.c was done so to allow p2p to
work. Now with the ability to specify ciphers in the AP config put the
burden on p2p to limit ciphers as it needs which is only CCMP according
to the spec.
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.
The validation of these ciphers for station is done when parsing
the BSS RSNE but for AP mode there is no such validation and
potentially any supported cipher could be chosen, even if its
incompatible for the type of key.
The netdev_copy_tk function was being hard coded with authenticator
set to false. This isn't important for any ciphers except TKIP but
now that AP mode supports TKIP it needs to be fixed.
Though TKIP is deprecated and insecure its trivial to support it in
AP mode as we already do in station. This is only to allow AP mode
for old hardware that may only support TKIP. If the hardware supports
any higher level cipher that will be chosen automatically.
The key descriptor version was hard coded to HMAC_SHA1_AES which
is correct when using IE_RSN_AKM_SUITE_PSK + CCMP. ap.c hard
codes the PSK AKM but still uses wiphy to select the cipher. In
theory there could be hardware that only supports TKIP which
would then make IWD non-compliant since a different key descriptor
version should be used with PSK + TKIP (HMAC_MD5_ARC4).
Now use a helper to sort out which key descriptor should be used
given the AKM and cipher suite.
Similarly to l_netconfig track whether IWD's netconfig is active (from
the moment of netconfig_configure() till netconfig_reset()) using a
"started" flag and avoid handling or emitting any events after "started"
is cleared.
This fixes an occasional issue with the Netconfig Agent backend where
station would reset netconfig, netconfig would issue DBus calls to clear
addresses and routes, station would go into DISCONNECTING, perhaps
finish and go into DISCONNECTED and after a while the DBus calls would
come back with an error which would cause a NETCONFIG_EVENT_FAILED
causing station to call netdev_disconnct() for a second time and
transition to and get stuck in DISCONNECTING.
Both CMD_ASSOCIATE and CMD_CONNECT paths were using very similar code to
build RSN specific attributes. Use a common function to build these
attributes to cut down on duplicated code.
While here, also start using ie_rsn_cipher_suite_to_cipher instead of
assuming that the pairwise / group ciphers can only be CCMP or TKIP.
Instead of copy-pasting the same basic operation (memcpy & assignment),
use a goto and a common path instead. This should also make it easier
for the compiler to optimize this function.
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.
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.
Parse the AP probe response offload attribute during the dump. If
set this indicates the driver expects the probe response attribute
to be included with START_AP.
Clearing all authentications during ft_authenticate was a very large
hammer and may remove cached authentications that could be used if
the current auth attempt fails.
For example the best BSS may have a problem and fail to authenticate
early with FT-over-DS, then fail with FT-over-Air. But another BSS
may have succeeded early with FT-over-DS. If ft_authenticate clears
all ft_infos that successful authentication will be lost.
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().
Once offchannel completes we can check if the info structure was
parsed, indicating authentication succeeded. If not there is no
reason to keep it around since IWD will either try another BSS or
fail.
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 finalizes the refactor by moving all the handshake prep
into FT itself (most was already in there). The netdev-specific
flags and state were added into netdev_ft_tx_associate which
now avoids any need for a netdev API related to FT.
The NETDEV_EVENT_FT_ROAMED event is now emitted once FT completes
(netdev_connect_ok). This did require moving the 'in_ft' flag
setting until after the keys are set into the kernel otherwise
netdev_connect_ok has no context as to if this was FT or some
other connection attempt.
In addition the prev_snonce was removed from netdev. Restoring
the snonce has no value once association begins. If association
fails it will result in a disconnect regardless which requires
a new snonce to be generated
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.
Now the full action frame including the header is provided to ft
which breaks the existing parser since it assumes the buffer starts
at the body of the message.
This forwards Action, Authentication and Association frames to
ft.c via their new hooks in netdev.
Note that this will break FT-over-Air temporarily since the
auth-proto still is in use.
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: 27d8cf4ccc ("scan: track scanned frequencies for entire request")
James Prestwood