In some cases, after a sudden AP disappearing and reconnection to
another AP in the same ESS, if another scan occurs, wpa_supplicant might
try to roam to the old AP (if it was better ranked than the new one)
because it is still saved in BSS list and the blacklist entry was
cleared in previous reconnect. This attempt is going to fail if the AP
is not present anymore and it'll cause long disconnections.
Remove an AP that is probably out of range from the BSS list to avoid
such disconnections. In particular mac80211-based drivers use the
WLAN_REASON_DISASSOC_DUE_TO_INACTIVITY reason code in locally generated
disconnection events for cases where the AP does not reply anymore.
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Fix possible memory leak in case if WPS is not enabled on the interface
for connection. This path was missed in commit
fae7b37260 ('WPS: Do not expire probable
BSSes for WPS connection').
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
When the BSS count reaches max_bss_count, the oldest BSS will be removed
in order to accommodate a new BSS. Exclude WPS enabled BSSes when going
through a WPS connection so that a possible WPS candidate will not be
lost.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Add a helper function to find a certain IE inside IEs buffer by ID and
use this function in several places that implemented similar
functionality locally.
Signed-off-by: Avraham Stern <avraham.stern@intel.com>
Reorder terms in a way that no invalid pointers are generated with
pos+len operations. end-pos is always defined (with a valid pos pointer)
while pos+len could end up pointing beyond the end pointer which would
be undefined behavior.
Signed-off-by: Jouni Malinen <j@w1.fi>
Do not expire scan results entries based on scan results from a scan
that was aborted. The aborted scan did not scan all the requested
channels or SSIDs, so the fact that a BSS is missing from the scan
results does not mean it is not available.
Signed-off-by: Avraham Stern <avraham.stern@intel.com>
This allows wpa_supplicant to expose internally unknown ANQP-elements in
the BSS command. For example, "ANQP_GET <BSSID> 265" can be used to
fetch the AP Geospatial Location ANQP-element and if the AP has this
information, the "BSS <BSSID>" command will include the response as
"anqp[265]=<hexdump>".
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
This allows a BSS entry to be expired if the AP has changed its SSID
while maintaining the same BSSID and we are associated with the BSS.
Previously, the same BSSID was enough to mark all BSS entries from the
BSSID as in use regardless of the SSID and as such, they could remain in
the wpa_supplicant BSS table indefinitely as long as the association
remaining.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Previously, one timeout per process (by default every 30 seconds) was
used P2P peer expiration and another per-interface timeout (every 10
seconds) was used to expire BSS entries. Merge these to a single
per-process timeout that triggers every 10 seconds to minimize number of
process wakeups due to periodic operations.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
These values were previously used only for sorting the scan results, but
it may be useful to provide access to the used values through the BSS
entries.
Signed-off-by: Jouni Malinen <j@w1.fi>
In addition, add support for returning the capability list through
the BSS control interface command.
Signed-off-by: ASHUTOSH NARAYAN <ashutoshx.narayan@intel.com>
In addition, add support for returning the capability list through the
BSS control interface command.
Signed-off-by: ASHUTOSH NARAYAN <ashutoshx.narayan@intel.com>
wpa_bss_in_use() used to determine that a BSS with BSSID of
00:00:00:00:00:00 is in use in almost every case since either
wpa_s->bssid or wpa_s->pending_bssid was likely to be cleared. This
could result in a corner case of a BSS entry remaining in the BSS table
indefinitely if one was added there with a (likely bogus) address of
00:00:00:00:00:00. Fix this by ignore wpa_s->bssid and
wpa_s->pending_bssid if the BSSID in the BSS table entry is
00:00:00:00:00:00.
In theory, that address is a valid BSSID, but it is unlikely to be used
in any production AP, so the potential expiration of a BSS entry with
that address during a connection attempt would not be a concern
(especially when a new scan would be enough to recover from that).
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
It is possible for scan result processing or BSS entry removal to occur
while there is a pending connect or sme-connect radio work with a
previously selected BSS entry. The BSS pointer was previously verified
to be valid, i.e., still point to a BSS entry, at the time the actual
connection operation is started. However, that BSS entry could have
changed to point to another BSS if the old BSS entry was either removed
or reallocated and a new BSS entry was added at the same location in
memory. This could result in the connection attempt failing to configure
parameters properly due to different BSS information (e.g., different
BSSID).
Fix this by updated the pending connect radio work data on BSS entry
updates similarly to how the last_scan_res array was updated. If the
selected BSS entry is removed, this will still result in a failed
connection, but reallocated BSS entry is now followed properly and used
when the connection work starts.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
"Age" is the age in seconds since the BSS was last seen, and is
emitted as a PropertyChanged signal whenever the BSS is updated
from a scan result. It also returns the correct age when queried
directly.
This property can be used to resolve issues where, if no other
properties of the BSS changed from scan results (for example,
if the BSS always had 100% signal) no D-Bus signals would be
emitted to indicate that the BSS had just been seen in the scan.
Signed-hostap: Dan Williams <dcbw@redhat.com>
The check based on last_scan_res_used is sufficient for making sure that
last_scan_res is allocated. However, it is a bit too complex for static
analyzers to notice, so add an explicit check to avoid bogus reports.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
If the BSS table within wpa_supplicant is flushed, request the driver to
flush its own scan result table during the next scan. This can avoid
unexpected old BSS entries showing up after BSS_FLUSH or FLUSH command
in cases where the driver may maintain its internal cache of scan
results (e.g., cfg80211 BSS table persists at least for 15 seconds).
In addition to doing this automatically on BSS_FLUSH/FLUSH, a new SCAN
command argument, only_new=1, can be used to request a manual scan
request to do same. Though, it should be noted that this maintains the
BSS table within wpa_supplicant. BSS_FLUSH followed by SCAN command can
be used to clear all BSS entries from both the driver and
wpa_supplicant.
Signed-hostap: Jouni Malinen <j@w1.fi>
This parameter was not really used for anything else apart from a debug
message in the same function that set it. In addition, cfg80211 returns
the set of scanned frequencies even for the full scan, so the code that
was setting this conditionally on frequency list not being there was not
really ever entered either.
Signed-hostap: Jouni Malinen <j@w1.fi>
This just serves to check if there was a scan within
the last 5 seconds, hence it should use monotonic time.
While at it, also use os_reltime_expired().
Signed-hostap: Johannes Berg <johannes.berg@intel.com>
The BSS table, scan timeout, and related functionality should use
monotonic time since they care about relative values (age) only.
Unfortunately, these are all connected, so the patch can't be split
further. Another problem with this is that it changes the driver wrapper
API. Though, it seems only the test driver is using this.
Signed-hostap: Johannes Berg <johannes.berg@intel.com>
It is possible that a P2P GO has been discovered through a non-P2P scan
that did not return P2P IE in Probe Response frames. To cover those
cases, check also Beacon frame (if received) for P2P IE.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
This could happen when non-P2P station interface runs a scan without P2P
IE in the Probe Request frame. P2P GO would reply to that with a Probe
Response that does not include P2P IE. Do not update the IEs in this BSS
entry to avoid such loss of information that may be needed for P2P
operations to determine group information.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
When the BSS table is being updated based on new scan results, a BSS
entry could end up getting added into last_scan_res list multiple times
if the scan results from the driver includes duplicated values. This
should not happen with driver_nl80211.c since it filter outs duplicates,
but in theory, other driver wrappers could indicate such scan results.
Anyway, it is safer to make sure this cannot happen by explicitly
verifying the last_scan_res list before adding an updated BSS entry
there. A duplicated entry in the list could potentially result in freed
memory being used if there is large enough number of BSSes in the scan
results to cause removal of old BSS entries.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
If there are large number of BSSes in the scan results, BSS table update
could have added a BSS entry to the last_scan_res in a case where that
BSS entry got just deleted. This would happen only if there are more
than bss_max_count (by default 200) BSSes and if at least bss_max_count
of those BSSes are known (match a configured network). In such a case,
wpa_bss_add() could end up allocating a new BSS entry and return a
pointer to that entry even if it was the one that ended up getting freed
to keep the BSS table length within the limit. This could result in
freed memory being used and the process crashing (likely with segfault)
when trying to access information from that BSS entry.
Fix the issue by removing the oldest BSS entry before linking the new
entry to the table. This makes sure the newly added entry will never get
picked up as the one to be deleted immediately.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
This can be used to configure wpa_supplicant to ignore old scan results
from the driver cache in cases where such results were not updated after
the scan trigger from wpa_supplicant. This can be useful in some cases
where the driver may cache information for a significant time and the AP
configuration is changing. Many such cases are for testing scripts, but
this could potentially be useful for some WPS use cases, too.
Signed-hostap: Jouni Malinen <j@w1.fi>
If the AP (P2P GO) has changes its channel of SSID recently, the BSS
table may have multiple entries for a BSSID. Select the one which was
most recently updated for WPS/P2P operations in such case to increase
the likelihood of using current information.
Signed-hostap: Jouni Malinen <j@w1.fi>
For various P2P use cases, it is useful to have more accurate timestamp
for the peer information update. This commit improves scan result
handling by using a single timestamp that is taken immediately after
fetching the results from the driver and then using that value to
calculate the time when the driver last updated the BSS entry. In
addition, more debug information is added for P2P peer updates to be
able to clearly see how old information is being used here.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
The RANGE=N1-N2 command did not return any entries in some cases where
N1 does not match with any BSS entry. Fix this by allow entries to be
fetched even without knowing the exact id values.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
When ANQP_GET or HS20_ANQP_GET is used to request ANQP information,
unshare the ANQP information (i.e., create a per-BSS copy of it) to
make sure the information from the specified BSS is available in case
the APs provide different information within HESSID.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
The BSS pointer may change if the entry needs to be reallocated
and the new pointer has to be added to the last_scan_res array
to avoid using pointers to freed memory.
Signed-hostap: Jouni Malinen <j@w1.fi>
This is an initial step in allowing the ANQP responses to be shared
among multiple BSSes if the BSSes are determined to be operating under
identical configuration.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
This allows last results to be used even after they have been freed
since the information is copied to the BSS entries anyway and this new
array provides the order in which scan results were processed.
Signed-hostap: Jouni Malinen <j@w1.fi>
When looking for a BSS to eject due to too many entries, never
pick one that is in use. Otherwise, we run the risk of having
pointers to freed data.
Signed-hostap: Paul Stewart <pstew@chromium.org>
For concurrency scenarios we should not update the scan results without
P2P IE to P2P group interfaces. This patch is to take care if a scan has
been requested on STA interface and scan results are getting updated
from sibling to P2P group interface. A P2P GO Probe Response for a
legacy STA scan would be without P2P IE. So it will wrongly update the
BSS list of P2P group interface too when results are updated from
sibling.
Since P2P group interfaces are used only for connecting to a P2P group,
it is fine to filter out all non-P2P entries from their BSS table.
Signed-off-by: Neeraj Garg <neerajkg@broadcom.com>
After reallocation of the bss struct, current_bss wasn't updated and
could hold an invalid pointer (which might get dereferenced later).
Update current_bss if the pointer was changed.
Signed-hostap: Eliad Peller <eliad@wizery.com>
intended-for: hostap-1
wpa_supplicant can now be configured to filter out scan results based
on a BSSID filter. Space-separated set of allowed BSSIDs can be set
with wpa_cli set bssid_filter command. Filtering mechanism can be
disabled by setting this variable to an empty list. When set, only
the BSSes that have a matching entry in this list will be accepted
from scan results.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
"BSS p2p_dev_addr=<P2P Device Address>" can now be used to fetch a
specific BSS entry based on the P2P Device Address of the GO to avoid
having to iterate through the full BSS table when an external program
needs to figure out whether a specific peer is currently operating as
a GO.
Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
Add mechanism for using GAS/ANQP to query Interworking related
information from APs. The received information is stored in the BSS
table and can be viewed with ctrl_iface BSS command.
New ctrl_iface command ANQP_GET can be used to fetch ANQP elements from
a specific AP. Additional commands FETCH_ANQP and STOP_FETCH_ANQP can be
used to initiate and stop an iteration through all APs in the BSS table
that indicate support Interworking to fetch ANQP elements from them.
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.
