Within mac80211, we often need to copy the rx status into
skb->cb. This is wasteful, as drivers could be building it
in there to start with. This patch changes the API so that
drivers are expected to pass the RX status in skb->cb, now
accessible as IEEE80211_SKB_RXCB(skb). It also updates all
drivers to pass the rx status in there, but only by making
them memcpy() it into place before the call to the receive
function (ieee80211_rx(_irqsafe)). Each driver can now be
optimised on its own schedule.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When changing to a new BSSID or SSID, the code in
ieee80211_set_disassoc() needs to have the old data
still valid to be able to disconnect and clean up
properly. Currently, however, the old data is thrown
away before ieee80211_set_disassoc() is ever called,
so fix that by calling the function _before_ the old
data is overwritten.

This is (one of) the issue(s) causing mac80211 to hold
cfg80211's BSS structs forever, and them thus being
returned in scan results after they're long gone.

http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=2015Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If we do not disconnect when a channel switch is requested,
we end up eventually detection beacon loss from the AP and
then disconnecting, without ever really telling the AP, so
we might just as well disconnect right away.

Additionally, this fixes a problem with iwlwifi where the
driver will clear some internal state on channel changes
like this and then get confused when we actually go clear
that state from mac80211.

It may look like this patch drops the no-IBSS check, but
that is already handled by cfg80211 in the wext handler it
provides for IBSS (cfg80211_ibss_wext_siwfreq).
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

It looks like some programs (e.g., NM) are setting an empty SSID with
SIOCSIWESSID in some cases. This seems to trigger mac80211 to try to
associate with an invalid configuration (wildcard SSID) which will
result in failing associations (or odd issues, potentially including
kernel panic with some drivers) if the AP were to actually accept this
anyway).

Only start association process if the SSID is actually set. This
speeds up connection with NM in number of cases and avoids sending out
broken association request frames.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When associated, but probing the AP because we detected
beacon loss, we need to disable powersave to be able to
receive the probe response. Change the code to do that by
checking whether we're trying to probe when determining
the possibility of going into PS, and recalculate the PS
ability at the necessary spots.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We don't want to trigger moving between PS mode during scan,
because then we will sometimes end up sending nullfunc frames
during scan. We're supposed to only send one prior to scan
and after scan.

This fixes an oops which occured due to an assert in ath9k:

http://marc.info/?l=linux-wireless&m=124277331319024

The assert was happening because the rate control algorithm
figures it should find at least one valid dual stream or
single stream rate. Since we allow mac80211 to send nullfunc
frames during scan and dynamic PS was enabled at times we ended
up trying to send nullfunc frames for the target sta on the
wrong band for which we have no valid rate to communicate with
it. This breaks the assumptions in rate control.

We determine we also need to disable moving between PS modes
when not associated so lets just add that now as well, and we
should not have a ps_sdata when that interface cannot actually
go into PS because it's not associated.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Always use the wiphy name instead.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

My first patch submission used 200ms, which I then somehow
managed to revert back to the earlier 50ms I had used for
some tests in the second patch submission -- but that was
wrong, I should have used 200ms here. Correct that.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In "mac80211: split out and decrease probe wait time" I tried
to reduce the time waiting for a probe response, but failed to
take into account the case where we are detecting beacon loss
in software -- in that case we still wait the monitoring time
rather than the probe wait time. Fix this by refactoring the
mod_timer() calls in ieee80211_associated().
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Currently, we will ask the driver to configure right away
when somebody changes the desired BSSID. That's totally
strange because then we will configure the driver without
even knowing whether the BSS exists. Change this to only
configure the BSSID when associated, and configure a zero
BSSID when not associated.

As a side effect, this fixes an issue with the iwlwifi
driver which doesn't implement sta_notify properly and
uses the BSSID instead and gets very confused if the
BSSID is cleared before we disassociate, which results
in the warning Marcel posted [1] and iwlwifi bug 1995 [2].

[1] http://thread.gmane.org/gmane.linux.kernel.wireless.general/32598
[2] http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1995

Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the genIE hasn't changed there's no reason to kick
the state machine since it won't be able to do anything
new -- doing this decreases the useless work we do for
reassociating because if we do kick the state machine
it will try to find a usable BSS but there might not be
one because wpa_supplicant will only change the BSSID
a little later.

In a sense this is a workaround for userspace behaviour,
but on the other hand userspace cannot really keep track
of what the kernel currently has for genIE since any
process could have changed that while wpa_supplicant
wasn't looking.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If the AP includes our AID in the TIM IE, we need to process the
Beacon frame as far as PS is concerned (send PS-Poll or nullfunc data
with PM=0). The previous code skipped this in cases where the CRC
value did not change and it would not change if the AP continues
including our AID in the TIM..

There is no need to count the crc32 value for directed_tim with this
change, so we can remove that part. In order not to change the order
of operations (i.e., update WMM parameters prior to sending PS-Poll),
the CRC match is checked twice as only after the PS processing step,
the rest of the function is skipped if nothing changed in the Beacon.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We forgot to cancel all timers in mac80211 when suspending.
In particular we forgot to deal with some things that can
cause hardware reconfiguration -- while it is down.

While at it we go ahead and add a warning in ieee80211_sta_work()
if its run while the suspend->resume cycle is in effect. This
should not happen and if it does it would indicate there is
a bug lurking in either mac80211 or mac80211 drivers.

With this now wpa_supplicant doesn't blink when I go to suspend
and resume where as before there where issues with some timers
running during the suspend->resume cycle. This caused a lot of
incorrect assumptions and would at times bring back the device
in an incoherent, but mostly recoverable, state.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The channel switch code is currently in the spectrum
management file, where arguably it belongs. However,
it is for managed mode only and uses the structures
for that mode only so having it in a more generic
file can be confusing. Additionally, my next patch
gets simpler with the code here.

When/if we ever implement this for IBSS or mesh then
we will need to rework the structures it uses anyway
at which point we could move the code back.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

While the probe request poll is expected to work, it looks like it
does not always result in getting a response. The exact reason for
this is unclear, but anyway, if we do receive a Beacon frame from our
AP, there is no need to disconnect based on the probereq poll. This
seems to help keep the connection bit more stable in cases where
beacon loss is occurring semi-frequently.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We weren't checking this at all.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This is more consistent with our nl80211 naming convention
for HT40-/+.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The time we wait for a probe response after probing an AP due to
beacon loss is currently the same as the monitoring interval, 2s.
This is far too long, APs should respond to probes within a
fraction of that time. To be able to adjust both values, add a
new constant IEEE80211_PROBE_WAIT, use it for checking the probe
response, and adjust it down to 200ms instead of 2 seconds.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The driver might keep reporting beacon loss until we
disassociate -- catch that and don't respond to any
subsequent events until the probe is either successful
or we disassociate.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add a new NL80211_ATTR_CONTROL_PORT flag for NL80211_CMD_ASSOCIATE to
allow user space to indicate that it will control the IEEE 802.1X port
in station mode. Previously, mac80211 was always marking the port
authorized in station mode. This was enough when drop_unencrypted flag
was set. However, drop_unencrypted can currently be controlled only
with WEXT and the current nl80211 design does not allow fully secure
configuration. Fix this by providing a mechanism for user space to
control the IEEE 802.1X port in station mode (i.e., do the same that
we are already doing in AP mode).
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When we disassociate, we set the channel to non-HT which
obviously invalidates any ht_operation_mode setting. But
when we then associate with the next AP again, we might
still have the ht_operation_mode from the previous AP
cached and fail to configure the hardware with the new
(but unchanged) operation mode. This patch fixes it by
separately tracking whether our cache is valid.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There really is no need to have a separate struct for a
single variable. The fact that it exists is due to the
code legacy, but we can remove that now. Very simple.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We've never really cared about the default QoS (WMM) values, but
we really should if the AP doesn't send any. This patch makes
mac80211 use the default values according to 802.11-2007, and
additionally syncs the default values when we disassociate so
whatever the last AP said gets "unconfigured".
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

net/mac80211/mlme.c:2079:28: warning: symbol 'ssid_len' shadows an earlier one
net/mac80211/mlme.c:2022:12: originally declared here

ssid_len is already being declared and checked above so there is
no need for it again.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When we aren't doing anything in mac80211, we can turn off
much of the hardware, depending on the driver/hw. Not doing
anything, aka being idle, means:

 * no monitor interfaces
 * no AP/mesh/wds interfaces
 * any station interfaces are in DISABLED state
 * any IBSS interfaces aren't trying to be in a network
 * we aren't trying to scan

By creating a new function that verifies these conditions and calling
it at strategic points where the states of those conditions change,
we can easily make mac80211 tell the driver when we are idle to save
power.

Additionally, this fixes a small quirk where a recalculated powersave
state is passed to the driver even if the hardware is about to stopped
completely.

This patch intentionally doesn't touch radio_enabled because that is
currently implemented to be a soft rfkill which is inappropriate here
when we need to be able to wake up with low latency.

One thing I'm not entirely sure about is this:

  phy0: device no longer idle - in use
  wlan0: direct probe to AP 00:11:24:91:07:4d try 1
  wlan0 direct probe responded
  wlan0: authenticate with AP 00:11:24:91:07:4d
  wlan0: authenticated
> phy0: device now idle
> phy0: device no longer idle - in use
  wlan0: associate with AP 00:11:24:91:07:4d
  wlan0: RX AssocResp from 00:11:24:91:07:4d (capab=0x401 status=0 aid=1)
  wlan0: associated

Is it appropriate to go into idle state for a short time when we have
just authenticated, but not associated yet? This happens only with the
userspace SME, because we cannot really know how long it will wait
before asking us to associate. Would going idle after a short timeout
be more appropriate? We may need to revisit this, depending on what
happens.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Due to the use of a _REQ_DIRECT_PROBE bit, which is
unnecessary (and I wonder why it was done that way),
an interesting situation can arise:
 1) we try to probe an access point
 2) the AP doesn't response in time
 3) we tell userspace that we gave up
 4) the AP suddenly responds
 5) we auth/assoc with the AP

I've seen 4) happen in testing with hostapd SIGSTOPped,
and when SIGCONTinued it processes the probe requests
that came in and send responses. But 5) is not supposed
to happen after we tell everybody we've given up on the
AP.

To fix this, remove the _REQ_DIRECT_PROBE request bit,
and process probe responses when we're in the relevant
MLME state, namely IEEE80211_STA_MLME_DIRECT_PROBE.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If the direct probe times out, we need to send the authentication
timeout event to notify SME in the same way as we notify on timeout
with authentication frames since the direct probe is run as part of
the authentication attempt.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In order to later add tracing or verifications to the driver
calls mac80211 makes, this patch adds static inline wrappers
for all operations.

All calls are now written as

	drv_<op>(local, ...);

instead of

	local->ops-><op>(&local->hw, ...);

Where necessary, the wrappers also do existence checking and
return default values as appropriate.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The config_interface method is a little strange, it contains the
BSSID and beacon updates, while bss_info_changed contains most
other BSS information for each interface. This patch removes
config_interface and rolls all the information it previously
passed to drivers into bss_info_changed.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We currently have two beacon interval configuration knobs:
hw.conf.beacon_int and vif.bss_info.beacon_int. This is
rather confusing, even though the former is used when we
beacon ourselves and the latter when we are associated to
an AP.

This just deprecates the hw.conf.beacon_int setting in favour
of always using vif.bss_info.beacon_int. Since it touches all
the beaconing IBSS code anyway, we can also add support for
the cfg80211 IBSS beacon interval configuration easily.

NOTE: The hw.conf.beacon_int setting is retained for now due
      to drivers still using it -- I couldn't untangle all
      drivers, some are updated in this patch.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There are some places marked
	/* XXX maybe racy? */
and they really are racy because there's no locking.

This patch reworks much of the scan code, and introduces proper
locking for the scan request as well as the internal scanning
(which is necessary for IBSS/managed modes). Helper functions
are added to call the scanning code whenever necessary. The
scan deferring is changed to simply queue the scanning work
instead of trying to start the scan in place, the scanning work
will then take care of the rest.

Also, currently when internal scans are requested for an interface
that is trying to associate, we reject such scans. This was not
intended, the mlme code has provisions to scan twice when it can't
find the BSS to associate with right away; this has never worked
properly. Fix this by not rejecting internal scan requests for an
interface that is associating.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Kalle points out that max_sleep_interval is somewhat confusing
because the value is measured in beacon intervals, and not in
TU. Rename it to max_sleep_period to be consistent with things
like DTIM period that are also measured in beacon intervals.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When somebody changes the PS parameters while scanning
is in progress, we enable PS -- during the scan. This
is clearly not desirable, and we can just abort enabling
PS when scanning since when the scan finishes it will
be taken care of.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Reviewed-by: NKalle Valo <kalle.valo@iki.fi>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

SME needs to be notified when the authentication or association
attempt times out and MLME has stopped processing in order to allow
the SME to decide what to do next.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The maximum sleep interval, for powersave purposes, is
determined by the DTIM period (it may not be larger)
and the required networking latency (it must be small
enough to fulfil those constraints).

This makes mac80211 calculate the maximum sleep interval
based on those constraints, and pass it to the driver.
Then the driver should instruct the device to sleep at
most that long.

Note that the device is responsible for aligning the
maximum sleep interval between DTIMs, we make sure it's
not longer but it needs to make sure it's between them.

Also, group some powersave documentation together and
make it more explicit that we support managed mode only,
and no IBSS powersaving (yet).
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Stephen Rothwell reported these warnings from a 32-bit build:

  net/mac80211/mlme.c:1771: warning: left shift count >= width of type
  net/mac80211/mlme.c:1772: warning: left shift count >= width of type
  net/mac80211/mlme.c:1773: warning: left shift count >= width of type
  net/mac80211/mlme.c:1774: warning: left shift count >= width of type
  net/mac80211/mlme.c:1775: warning: left shift count >= width of type

This shows a bug in my code -- BIT(X) uses just "1 << X" which means
a 32-bit integer on 32-bit platforms, but the code here needs a u64
on all platforms. Fix this by using "1ULL << X" instead of BIT(X).

Thanks Stephen!
Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The TIM IE must not be shorter than 4 bytes, so verify that
when parsing it and use the proper type. To ease that adjust
struct ieee80211_tim_ie to have a virtual bitmap of size
at least 1.

Also check that the TIM IE is actually present before trying
to parse it!

Because other people may need the function, make it a static
inline in ieee80211.h.

(The original "mac80211: validate TIM IE length" was a minimal fix for
2.6.30.  This purports to be the full, correct fix. -- JWL)
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since we have ->deauth and ->disassoc we can support the
wext SIWMLME call directly without driver wext handlers.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Enable PS by default (depending on Kconfig) -- rely on drivers
to control the level using pm_qos. Due to the previous patch
we turn off PS when necessary due to latency requirements.

This has a Kconfig symbol so people can, if they really want,
configure the default in their kernels. We may want to keep it
at "default y" only in wireless-testing for a while.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Regardless of whether the hardware implements beacon filtering,
there's no need to process all beacons in software all the time
throughout the stack (mac80211 does a lot, then cfg80211, then
in the future possibly userspace).

This patch implements the "best possible" beacon filtering in
mac80211. "Best possible" means that it can look for changes in
all requested information elements, and distinguish vendor IEs
by their OUI.

In the future, we will add nl80211 API for userspace to request
information elements and vendor IE OUIs to watch -- drivers can
then implement the best they can do while software implements
it fully.

It is unclear whether or not this actually saves CPU time, but
the data is all in the cache already so it should be fairly
cheap. The additional _testing_, however, has great benefit;
Without this, and on hardware that doesn't implement beacon
filtering, wrong assumptions about, for example, scan result
updates could quickly creep into code.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>