Currently, when the driver requires the DTIM period,
mac80211 will wait to hear a beacon before association.
This behavior is suboptimal since some drivers may be
able to deal with knowing the DTIM period after the
association, if they get it at all.

To address this, notify the drivers with bss_info_changed
with the new BSS_CHANGED_DTIM_PERIOD flag when the DTIM
becomes known. This might be when changing to associated,
or later when the entire association was done with only
probe response information.

Rename the hardware flag for the current behaviour to
IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC to more accurately
reflect its behaviour. IEEE80211_HW_NEED_DTIM_PERIOD is
no longer accurate as all drivers get the DTIM period
now, just not before association.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The field is never used, so remove it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's no need to have two checks for "associated"
in ieee80211_sta_restart(), make the first one locked
to not race (unlikely at this point during resume)
and remove the second check.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

For drivers that don't actually flush their queues when
aggregation stop with the IEEE80211_AMPDU_TX_STOP_FLUSH
or IEEE80211_AMPDU_TX_STOP_FLUSH_CONT reasons is done,
like iwlwifi or iwlegacy, mac80211 can then transmit on
a TID that the driver still considers busy. This happens
in the following way:

 - IEEE80211_AMPDU_TX_STOP_FLUSH requested
 - driver marks TID as emptying
 - mac80211 removes tid_tx data, this can copy packets
   to the TX pending queues and also let new packets
   through to the driver
 - driver gets unexpected TX as it wasn't completely
   converted to the new API

In iwlwifi, this lead to the following warning:

WARNING: at drivers/net/wireless/iwlwifi/dvm/tx.c:442 iwlagn_tx_skb+0xc47/0xce0
Tx while agg.state = 4
Modules linked in: [...]
Pid: 0, comm: kworker/0:0 Tainted: G        W   3.1.0 #1
Call Trace:
 [<c1046e42>] warn_slowpath_common+0x72/0xa0
 [<c1046f13>] warn_slowpath_fmt+0x33/0x40
 [<fddffa17>] iwlagn_tx_skb+0xc47/0xce0 [iwldvm]
 [<fddfcaa3>] iwlagn_mac_tx+0x23/0x40 [iwldvm]
 [<fd8c98b6>] __ieee80211_tx+0xf6/0x3c0 [mac80211]
 [<fd8cbe00>] ieee80211_tx+0xd0/0x100 [mac80211]
 [<fd8cc176>] ieee80211_xmit+0x96/0xe0 [mac80211]
 [<fd8cc578>] ieee80211_subif_start_xmit+0x348/0xc80 [mac80211]
 [<c1445207>] dev_hard_start_xmit+0x337/0x6d0
 [<c145eee9>] sch_direct_xmit+0xa9/0x210
 [<c14462c0>] dev_queue_xmit+0x1b0/0x8e0

Fortunately, solving this problem is easy as the station
is being destroyed, so such transmit packets can only
happen due to races. Instead of trying to close the race
just let the race not reach the drivers by making two
changes:
 1) remove the explicit aggregation session teardown in
    the managed mode code, the same thing will be done
    when the station is removed, in __sta_info_destroy.
 2) When aggregation stop with AGG_STOP_DESTROY_STA is
    requested, leave the tid_tx data around as stopped.
    It will be cleared and freed in cleanup_single_sta
    later, but until then any racy packets will be put
    onto the tid_tx pending queue instead of transmitted
    which is fine since the station is being removed.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since drivers can support several BSS / P2P Client
interfaces, the rssi callback needs to inform the driver
about the interface teh rssi event relates to.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Depending on the driver, having ARP filtering for
some addresses may be possible. Remove the logic
that tracks whether ARP filter is enabled or not
and give the driver the total number of addresses
instead of the length of the list so it can make
its own decision.
Reviewed-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

My commit 4bf88530
("mac80211: convert to channel definition struct")
accidentally broke HT40 connections due to swapped
channel flag checks -- fix that.
Reported-by: NSujith Manoharan <sujith@msujith.org>
Tested-by: NSujith Manoharan <sujith@msujith.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The initiator/tx doesn't really identify why an
aggregation session is stopped, give a reason
for stopping that more clearly identifies what's
going on. This will help tell the driver clearly
what is expected of it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In interoperability testing some APs showed bad behaviour
if some of the VHT capabilities of the station are better
than their own. Restrict the assoc request parameters
 - beamformee capabable,
 - RX STBC and
 - RX MCS set
to the subset that the AP can support.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The probe response/beacon management frame RX code passes a
bool parameter to differentiate beacons and probe responses.
This is useless since we have the frame and can thus use its
frame control field. Moreover it is buggy since there is one
call to ieee80211_rx_bss_info with a beacon frame that is
indicated as a probe response, which is also fixed by using
the frame control field, so do that.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The last fixes re-added the RCU synchronize penalty
on roaming to fix the races. Split up sta_info_flush()
now to get rid of that again, and let managed mode
(and only it) delay the actual destruction.
Tested-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When all interfaces have been removed, there can't
be any stations left over, so there's no need to
flush again. Remove this, and all code associated
with it, which also simplifies the function.
Tested-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When AP's SSID is hidden the BSS can appear several times in
cfg80211's BSS list: once with a zero-length SSID that comes
from the beacon, and once for each SSID from probe reponses.

Since the mac80211 stores its data in ieee80211_bss which
is embedded into cfg80211_bss, mac80211's data will be
duplicated too.

This becomes a problem when a driver needs the dtim_period
since this data exists only in the beacon's instance in
cfg80211 bss table which isn't the instance that is used
when associating.

Remove the DTIM period from the BSS table and track it
explicitly to avoid this problem.

Cc: stable@vger.kernel.org
Tested-by: NEfi Tubul <efi.tubul@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If channel contexts are enabled, the CSA should not be processed
further. A return is missing here.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When a BSS struct is updated, the IEs are currently
overwritten or freed. This can lead to races if some
other CPU is accessing the BSS struct and using the
IEs concurrently.

Fix this by always allocating the IEs in a new struct
that holds the data and length and protecting access
to this new struct with RCU.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Determine the VHT channel from the AP's VHT operation IE
(if present) and configure the hardware to that channel
if it is supported. If channel contexts cause a channel
to not be usable, try a smaller bandwidth.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Convert mac80211 (and where necessary, some drivers a
little bit) to the new channel definition struct.

This will allow extending mac80211 for VHT, which is
currently restricted to channel contexts since there
are no drivers using that which makes it easier. As
I also don't care about VHT for drivers not using the
channel context API, I won't convert the previous API
to VHT support.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If ieee80211_prep_channel() decides that HT should be
disabled (because the HT IEs from the AP were invalid)
it will set the IEEE80211_STA_DISABLE_HT to not send
HT capabilities to the AP when associating. If this
happens during authentication, the flag will be lost
and we send HT frames, even if the channel config was
set up for non-HT. This can lead to issues.

Fix this by always resetting the ifmgd flags to zero
when the channel context is released so that the flag
resetting in ieee80211_mgd_assoc() isn't necessary.

To make the code a bit easier move the call to release
the channel in ieee80211_set_disassoc() to the end of
the function together with the flag resetting (which
needs to be at the end to avoid timers setting flags.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If the AP doesn't support HT, or more importantly if
it does but we have to disable it because its IEs are
broken, don't advertise HT support in our association
request. Otherwise, we configure our channel to be a
20 MHz non-HT channel but the AP might still think we
support HT, or even 40 MHz.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since the 11n spec amendment was rolled into the
2012 version, "11n" no longer makes sense. Use
"HT" instead.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If the driver doesn't support 40 MHz channels, then
mac80211 erroneously sets number of RX chains to one
although the number of chains is independent of the
support for 40 MHz channels.

Fix this by checking the 40 MHz support only for the
code that sets the 40 MHz channel not the complete
HT code block.

This also means the HT20 channel type will always be
set in the changed code block so there's no need to
set it in case we override the AP due to invalid IEs
in the probe response/beacon.

The indentation is a bit quirky, but I'm rewriting
this code for VHT support so this will change again
very soon.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

While connected to a GO, parse the P2P NoA attribute
and pass the CT Window and opportunistic powersave
parameters to the driver.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When userspace asks to deauthenticate and we're just
authenticated (or still authenticating) send a deauth
frame instead of deleting the auth request.

On the other hand, if we've just disassociated and
therefore deleted all our state already, drop the
deauth request because we no longer have a channel
context to send it on.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Even before channel contexts/multi-channel, having a
single global TX power limit was already problematic,
in particular if two managed interfaces connected to
two APs with different power constraints. The channel
context introduction completely broke this though and
in fact I had disabled TX power configuration there
for drivers using channel contexts.

Change everything to track TX power per interface so
that different user settings and different channel
maxima are treated correctly. Also continue tracking
the global TX power though for compatibility with
applications that attempt to configure the wiphy's
TX power globally.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Remove a duplicate check in ieee80211_rx_mgmt_beacon,
there is no need to make again the same check for the
IEEE80211_HW_PS_NULLFUNC_STACK twice; the two ifs can
be consolidated.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
[reword commit message & break long lines and also
 clean up variable]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There are a number of unused variables that gcc
pointed out (when building with W=1) as well as
some conditions that can never be true due to
the datatypes used: unsigned values can't be
less than zero. Remove this code.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Some changes to fix issues with HT40 APs in Korea
and follow-up changes to allow using HT40 even if
the local regulatory database disallows it caused
issues with iwlwifi (and could cause issues with
other devices); iwlwifi firmware would assert if
you tried to connect to an AP that has an invalid
configuration (e.g. using HT40- on channel 140.)

Fix this, while avoiding the "Korean AP" issue by
disabling HT40 and advertising HT20 to the AP
when connecting.

Cc: stable@vger.kernel.org [3.6]
Reported-by: NFlorian Reitmeir <florian@reitmeir.org>
Tested-by: NFlorian Reitmeir <florian@reitmeir.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Save the AP's VHT capabilities (in managed
mode) and make them available to the driver
in the station information.

Unlike HT capabilities, they aren't restricted
to the common capabilities, so drivers must be
aware of their own capabilities.
Signed-off-by: NMahesh Palivela <maheshp@posedge.com>
[fix endian conversion bug ...]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Rename struct ieee80211_vht_capabilities to ieee80211_vht_cap
and renamed its member vht_capabilities_info to vht_cap_info.
Signed-off-by: NMahesh Palivela <maheshp@posedge.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

SAE uses two rounds of Authentication frames and both rounds require
considerable calculation to be done. This commit extends the existing
station mode authentication request to allow more control for user
space programs to build the SAE fields and to run the authentication
step ones. Only the second round with authentication transaction
sequence 2 will result in moving to authenticated state.
Signed-off-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This is useful when debugging authentication process issues.
Signed-off-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Non-zero status code may be needed for Authentication frames, e.g.,
when using SAE.
Signed-off-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

On each channel that the device is operating on, it
may need to listen using one or more chains depending
on the SMPS settings of the interfaces using it. The
previous channel context changes completely removed
this ability (before, it was available as the SMPS
mode).

Add per-context tracking of the required static and
dynamic RX chains and notify the driver on changes.
To achieve this, track the chains and SMPS mode used
on each virtual interface and update the channel
context whenever this changes.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Instead of operating on a single channel only,
use the new channel context infrastructure in
all mac80211 code.

This enables drivers that want to use the new
channel context infrastructure to use multiple
channels, while nothing should change for all
the other drivers that don't support it.

Right now this disables both TX power settings
and spatial multiplexing powersave. Both need
to be re-enabled on a channel context basis.

Additionally, when channel contexts are used
drop the connection when channel switch is
received rather than trying to handle it. This
will have to be improved later.

[With fixes from Eliad and Emmanuel incorporated]
Signed-off-by: NEliad Peller <eliad@wizery.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Avoid situation when we are on associate state in mac80211 and
on disassociate state in cfg80211. This can results on crash
during modules unload (like showed on this thread:
http://marc.info/?t=134373976300001&r=1&w=2) and possibly other
problems.
Reported-by: NPedro Francisco <pedrogfrancisco@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When we disassociate, it's not really useful to
send delBA action frames since we're going to send
disassoc/deauth anyway, so change that.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Make the function acquire the necessary mutex itself
to simplify the callers.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently, mac80211 uses the power constraint IE, and reduces
the regulatory max TX power by it. This can cause issues if
the AP is advertising a large power constraint value matching
a high TX power in its country IE, for example in this case:

...
Country: US  Environment: Indoor/Outdoor
    ...
    Channels [157 - 157] @ 30 dBm
    ...
Power constraint: 13 dB
...

What happened here is that our local regulatory TX power is
15 dBm, and gets reduced by 13 dB so we end up with only
2 dBm effective TX power, which is way too low.

Instead, handle the country IE/power constraint IE combined
and restrict our TX power to the max of the regulatory power
and the maximum power advertised by the AP, in this case
17 dBm (= 30 dBm - 13 dB).

Also print a message when this happens to let the user know
and help us debug issues with it.
Reported-by: NCarl A. Cook <CACook@quantum-equities.com>
Tested-by: NCarl A. Cook <CACook@quantum-equities.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Move ieee80211_send_deauth_disassoc() to util.c to make it
available for the rest of the mac80211 code.
Signed-off-by: NAntonio Quartulli <ordex@autistici.org>
[reword commit message]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>