When the BSS table size limit has been reached, drop first the oldest
BSS entries for which there is not a matching network in the
configuration based on SSID (wildcards are ignored). This makes it
less likely to hit connection issues in environments with huge number
of visible APs.
When comparing BSS table entries, handle empty concatenated
vendor-specific IE differently from completely missing IE. This
does not change anything for the only currently compared IE that
can be fragmented (WPS IE), but it is better to have the generic
code here ready for any possible new IE that could be used in
with zero-length data.
Replace compile-time BSS cache expiration age and scan count by config
parameters that can be set via wpa_cli and the new D-Bus API. The latter
is done with interface properties BSSExpireAge and BSSExpireCount.
This fixes an issue seen in our wifi testbed, where we frequently
switch the SSID of the AP. wpa_supplicant's BSS list will have, for
example both <bssid, "Check11b"> (from the previous test) and <bssid,
"Check11g"> (from the current test) - note that the bssid is the same for
both. The (old) D-Bus API for fetching scan responses from wpa_supplicant
is fetch-by-bssid, so the caller (flimflam) incorrectly believes we're
associated with <bssid, "Check11b">.
Add an "Interface.FlushBSS" method to the new D-Bus API and a "flush"
method to the old API. Both take an age parameter that is a threshold
(in seconds) for selecting entries to evict. Setting this parameter
to zero flushes all entries from the cache.
This mechanism is useful for a connection manager to clear state at
startup and on resume (where the age parameter may be used to hold
onto recent/valid data).
This converts number of debugging messages to use wpa_msg() in order
to allow the interface name to be shown with the messages.
A new function, wpa_dbg(), is introduced to allow
CONFIG_NO_STDOUT_DEBUG=y builds to remove the debug strings. This is
otherwise identical with wpa_msg(), but it gets compiled out if stdout
debugging is disabled.
New global configuration parameter bss_max_count can now be used to
change the maximum BSS table size. The old fixed size limit (200) is
used as the default value for this parameter.
Expose RSN and WPA properties for BSS objects containing information
about key management and cipher suites. Get rid of WPA/RSN/WPSIE
byte array properties and add IEs byte array property with all IE data
instead.
This allows the driver wrappers to return two sets of IEs, so that
the BSS code can use information from both Beacon and Probe Response
frames if needed. For example, some Cisco APs seem to include more
information in Wireless Provisioning Services IE when it is in the
Beacon frame.
Most of this file was already moved into wpa_supplicant/scan.c and
we can remove the file completely by having couple of small helper
functions copied to the remaining users outside core wpa_supplicant
code.
The wpa_s->bss_id list was being corrupted when the BSS entry needed
to be reallocated due to longer IE data. The entry has to be removed
from all lists before reallocation to avoid this (it was only removed
from the wpa_s->bss list).
Get more information about scans when updating BSS table information.
This allows the missing-from-scans expiration rule to work properly
when only partial set of channels or SSIDs are being scanned.
This allows the BSS list to be iterated in order of increasing id
to avoid problems with new scans reordering entries. The order on the
wpa_s->bss list changes with most recently updated entries being moved
to the tail of the list while wpa_s->bss_id list maintains its order
with new entries being added to the tail and old entries being removed
when they expire.
Collect information from scan results into a BSS table that will not
expire information as quickly as scan results where every new scan,
no matter for how limited set of channels/SSIDs, clears all old
information.
For now, this is only used for D-Bus BSS added/removed notifications,
but this will likely be extended to be used internally instead of the
scan results to better support partial scans.
