When updating the network ranking there was a potential out of bounds
array access. The condition was if known_network_offset returned a
negative value, indicating the known network was not found. Since
network->info is only set for known networks this should not ever
happen as network->info is checked prior.
Though this is likely impossible, knownnetworks is complex enough that
its better to just be paranoid and put an L_WARN_ON to check the
return.
This lets other modules (like WSC) to set a plain text passphrase
as opposed to only allowing a PSK to be set. network_get_psk was
also updated to generate a PSK on-the-fly if required. Since WPA3
requires the raw passphrase to work, it makes sense to just store
the passphrase if we have it.
The UUID was being generated every time we synced which is wasteful.
Instead we can track the UUID inside network_info and only generate
it once when needed.
Two new network_info APIs were added:
network_info_set_uuid
network_info_get_uuid
The setter is used when the frequency file is loaded. If a valid UUID
is found in the frequency file this UUID is set and used.
network_info_get_uuid will not just get the UUID, but actually generate
it if one has not been set yet. This will allow other modules to
get/generate the UUID if one has no been loaded from the frequency
file.
The existing frequency syncing was done when IWD closes. Instead we
can sync as networks are connected to or promoted to known which
will keep the FS more up to date. This also allows hotspot networks
to use the known frequency file.
The HS20 module had its own getter for returning the matched roaming
consortium. Since we already have the network_info op for matching
we might as well return the matched RC rather than just a bool. This
allows the RC to be included in (Re)Association without the need for
a specific getter.
After wsc_store_credentials, wsc_try_credentials is called which
sets the PSK obtained via the protocol. After the known network
refactor network_settings_load was changed to depend on the
network_info->open() call. Since there is no known network for
this initial WSC connection this always fails and the PSK is not
set into the network object (and the connection is failed).
In this case if network_settings_load fails we can just create
an empty settings object to be filled later.
Rather than using timespec directly, ELL has a convenient API
to get the elapsed microseconds as a uint64_t. This can then
be used with the other l_time_ APIs for comparison.
This patch removes timespec from network_info and updates
to use l_time_* API's for sorting.
The known network APIs all revolved around the ssid/security matching
to do any operations on the provisioning file. In the near future
hotspot provisioning files (managed by hotspot.c) will be incorporated
into the known network list. Since these hotspot files do not use the
ssid as the file name hotspot.c will need other ways of matching.
This patch adds network_info_ops to the network object. This ops
structure will hold function pointers which operate on network_info
rather than ssid/security. This will allow hotspot and known networks
to both register their own operation routines.
For now open, touch, sync, remove, free, and get_path were added.
Wrappers were added for accessing these operations outside of
knownnetworks.c.
Isolate the known_frequency queue management to a function and place
that function in knownnetworks.c where it now belongs. Since we no
longer have network_info objects for unknown networks, only frequencies
for known networks are tracked
networks queue was intended to share basic network information between
multiple adapters running simultaneously. The network_info object was
also serving double duty to carry known network information. This made
things overly complicated and really didn't result in much savings.
This setup also made managing hotspot networks challenging as we would
have ended up with multiple network_info objects for each known hotspot
network.
So get rid of the networks queue and the is_known bit from the
network_info structure.
network_find_rank_index was used to find the offset of the selected
network_info among known networks so as to compute a modifier based on
the rankmod table. Instead of using known_networks_foreach for this,
moove it to knownnetworks.c where it can be coded and optimized
separately.
For now provide a simple for loop implementation.
For (Re)Association the HS20 indication element was passed exactly as
it was found in the scan results. The spec defines what bits can be
set and what cannot when this IE is used in (Re)Association. Instead
of assuming the AP's IE conforms to the spec, we now parse the IE and
re-build it for use with (Re)Association.
Since the full IE is no longer used, it was removed from scan_bss, and
replaced with a bit for HS20 support (hs20_capable). This member is
now used the same as hs20_ie was.
The version parsed during scan results is now used when building the
(Re)Association IE.
Previously, iwd used to throw net.connman.iwd.Busy when connection
attempt was made while connected. The new behavior allows iwd to
seamlessly disconnect from the connected network and attempt a new
connection.
Since NAI realms, Roaming Consortium and HESSID are defined in 802.11,
they are not a guarentee that the network is Hotspot 2.0. The indication
element in addition to these IE's gives a better idea of Hotspot 2.0
support. Now, when a BSS is added this is_hs20 boolean will get set to
true if the HS20 IE was found in the BSS.
Now, if is_hs20 is set AND one of NAI realms, roaming consortium, or
HESSID is set we know this is a hotspot 2.0 network.
This is duplicated when the first scan_bss is added to a network
object that contains the IE. Any future BSS's added will not re-add
the IE. Its assumed that all BSS's under a network will contain the
same roaming consortium OIs.
Hotspot networks are supposed to include an HESSID in the scan
results. This is more or less an identifier for the overall
network. In addition, the NAI Realms can be obtained via ANQP
and should be the same for each BSS. Since both HESSID and NAI
realms should be the same for a given network in range we can
store these values in the network object itself. This also allows
us to easily find hotspot configuration files by looking at
the HESSID/NAI Realms directly in the network object as opposed
to individual scan_bss's.
Each known network (previously connected) will have a set
of known frequencies associated with it, e.g. a set of
frequencies from all BSSs observed. The list of known
frequencies is sorted with the most recently observed
frequency in the head.
Certain error conditions require that a BSS be blacklisted only for
the duration of the current connection. The existing blacklist
does not allow for this, and since this blacklist is shared between
all interfaces it doesnt make sense to use it for this purpose.
Instead, each network object can contain its own blacklist of
scan_bss elements. New elements can be added with network_blacklist_add.
The blacklist is cleared when the connection completes, either
successfully or not.
Now inside network_bss_select both the per-network blacklist as well as
the global blacklist will be checked before returning a BSS.
If we have a BSS list where all BSS's have been blacklisted we still
need a way to force a connection to that network, instead of having
to wait for the blacklist entry to expire. network_bss_select now
takes a boolean 'fallback_to_blacklist' which causes the selection
to still return a connectable BSS even if the entire list was
blacklisted.
In most cases this is set to true, as these cases are initiated by
DBus calls. The only case where this is not true is inside
station_try_next_bss, where we do want to honor the blacklist.
This both prevents an explicit connect call (where all BSS's are
blacklisted) from trying all the blacklisted BSS's, as well as the
autoconnect case where we simply should not try to connect if all
the BSS's are blacklisted.
There are is some implied behavior here that may not be obvious:
On an explicit DBus connect call IWD will attempt to connect to
any non-blacklisted BSS found under the network. If unsuccessful,
the current BSS will be blacklisted and IWD will try the next
in the list. This will repeat until all BSS's are blacklisted,
and in this case the connect call will fail.
If a connect is tried again when all BSS's are blacklisted IWD
will attempt to connect to the first connectable blacklisted
BSS, and if this fails the connect call will fail. No more
connection attempts will happen until the next DBus call.
If IWD fails to connect to a BSS we can attempt to connect to a different
BSS under the same network and blacklist the first BSS. In the case of an
incorrect PSK (MMPDU code 2 or 23) we will still fail the connection.
station_connect_cb was refactored to better handle the dbus case. Now the
netdev result switch statement is handled before deciding whether to send
a dbus reply. This allows for both cases where we are trying to connect
to the next BSS in autoconnect, as well as in the dbus case.
If a network is being forgotten, then make sure to reset connected_time.
Otherwise the rank logic thinks that the network is known which can
result in network_find_rank_index returning -1.
Found by sanitizer:
src/network.c:1329:23: runtime error: index -1 out of bounds for type
'double [64]'
In the name of failing earlier try to generate the PSK from the
passphrase as soon as we receive the passphrase or read it from the
file, mainly to validate it has the right number of characters.
The passphrase length currently gets validates inside
crypto_psk_from_passphrase which will be called when we receive a new
passphrase from the agent or when the config file has no PSK in it. We
do not do this when there's already both the PSK and the passphrase
available in the settings -- we can add that separately if needed.
James Prestwood