When an injected frame gets buffered for a powersave STA or filtered
and retransmitted, mac80211 attempts to parse the radiotap header
again, which doesn't work because it's gone at that point.
This patch adds a new flag for checking the availability of a radiotap
header, so that it only attempts to parse it once, reusing the tx info
on the next call to ieee80211_tx().
This fixes severe issues with rekeying in AP mode.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

What a stupid mistake. In

    commit 813d7669
    Author: Johannes Berg <johannes@sipsolutions.net>
    Date:   Sun Jan 17 01:47:58 2010 +0100

        mac80211: move control.hw_key assignment

I inserted code testing the wrong flags field,
which means that the test is almost always true
(it's really testing for the peer's WMM support)
and thus the later parts of the stack assume hw
crypto will be done even if that's not true.

Obviously, that broke software crypto. Maxim
said so specifically, and Jochen probably uses
some cipher that iwl3945 doesn't support in
hardware, which might also explain that Maxim
reports that even hw crypto is broken.

Fix this to test the right flags field.
Reported-by: NMaxim Levitsky <maximlevitsky@gmail.com>
Reported-by: NJochen Friedrich <jochen@scram.de>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Pavel Roskin reported a crash in ieee80211_tx_h_select_key():

http://marc.info/?l=linux-wireless&m=126419655108528&w=2

This is a regression from patch "mac80211: move control.hw_key assignment".
Fix it as suggested by Johannes, adding an else statement to make sure
that tx->key is not accessed when it's null.

Compile-tested only.
Reported-by: NPavel Roskin <proski@gnu.org>
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: NKalle Valo <kalle.valo@iki.fi>
Tested-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ieee80211_tx_h_select_key might decide that a frame
need not be encrypted at all, in which case it will
clear tx->key. In that case it may crash if a key
was previously selected, e.g. as the default key.

This is also due to my patch
"mac80211: move control.hw_key assignment".
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In an earlier commit,

    mac80211: disable software retry for now

    Pavel Roskin reported a problem that seems to be due to
    software retry of already transmitted frames. It turns
    out that we've never done that correctly, but due to
    some recent changes it now crashes in the TX code. I've
    added a comment in the patch that explains the problem
    better and also points to possible solutions -- which
    I can't implement right now.

I disabled software retry of failed/filtered frames
because it was broken. With the work of the previous
patches, it now becomes fairly easy to re-enable it
by adding a flag indicating that the frame shouldn't
be modified, but still running it through the transmit
handlers to populate the control information.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When mac80211 asks a driver to encrypt a frame, it
must assign the control.hw_key pointer for it to
know which key to use etc. Currently, mac80211 does
this whenever it would software-encrypt a frame.

Change the logic of this code to assign the hw_key
pointer when selecting the key, and later check it
when deciding whether to encrypt the frame or let
it be encrypted by the hardware. This allows us to
later simply skip the encryption function since it
no longer modifies the TX control.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There's no value in setting a flag that will
never be checked after this point, this seems
to be legacy code -- I think previously the
flag was used to check whether to encrypt the
frame or not. Now, however, the flag need not
be set, and setting it actually interferes if
the frame will be processed again later.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This TX handler is used only for assigning the
station pointer in the control information, so
give it a better name. Also move it before rate
control.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

To make U-APSD client mode effective, we must not wake up from dynamic power
save when transmitting frames. So if dynamic power save is enabled, it needs
check the queue the transmitted packet is in and decide if we need to wake
up or not.

In a perfect world, where all packets would have correct QoS tags, U-APSD
enabled queues should not trigger wakeup from power save. But in the real
world, where very few packets have correct QoS tags, this won't work. For
example, if only voip class has U-APSD enabled and we send a packet in voip
class, but the packets we receive are in best effort class, we would receive
the packets with the legacy power save method. And that would increase
latencies too much from a voip application point of view.

The workaround is to enable U-APSD for all qeueus and still use dynamic ps
wakeup for all other queues except voip. That way we can still save power
with a voip application and not sacrifice latency. Normal traffic (in
background, best effort or video class) would still trigger wakeup from
dynamic power save.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Currently dynamic ps check is in ieee80211_xmit(), but it's cleaner
to have a separate tx handler for this. Also this is a prerequisite for
U-APSD client mode which needs to know the queue frame is in.

Also need_dynamic_ps() function is embedded to the tx handler.

No functional changes expect that the code is run in a later phase than
originally.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If frames are transmitted on 4-addr ap vlan interfaces with no station,
they end up being transmitted unencrypted, even if the ap interface
uses WPA. This patch add some sanity checking to make sure that this
does not happen.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Certain type of hardware, for example wl1251 and wl1271, need a template
for the Probe Request. Create a function ieee80211_probereq_get() which
creates the template and drivers send it to hardware.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some hardware, for example wl1251 and wl1271, handle the transmission
of power save related frames in hardware, but the driver is responsible
for creating the templates. It's better to create the templates in mac80211,
that way all drivers can benefit from this.

Add two new functions, ieee80211_pspoll_get() and ieee80211_nullfunc_get()
which drivers need to call to get the frame. Drivers are also responsible
for updating the templates after each association.

Also new struct ieee80211_hdr_3addr is added to ieee80211.h to make it
easy to calculate length of the Nullfunc frame.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Extend struct cfg80211_bitrate_mask to actually use a bitfield mask
instead of just a single fixed or maximum rate index. This change
itself does not modify the behavior (except for debugfs files), but it
prepares cfg80211 and mac80211 for a new nl80211 command for setting
which rates can be used in TX rate control.

Since frames are now going through the rate control algorithm
unconditionally, the internal IEEE80211_TX_INTFL_RCALGO flag can now
be removed. The RC implementations can use the rate_idx_mask value to
optimize their behavior if only a single rate is enabled.

The old max_rate_idx in struct ieee80211_tx_rate_control is maintained
(but commented as deprecated) for backwards compatibility with existing
RC implementations. Once these implementations have been updated to
use the more generic rate_idx_mask, the max_rate_idx value can be
removed.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If the basic rate set is configured to not include the lowest rate
(e.g., basic rate set = 6, 12, 24 Mbps in IEEE 802.11g mode), the AP
should not send out broadcast frames at 1 Mbps. This type of
configuration can be used to optimize channel usage in cases where
there is no need for backwards compatibility with IEEE 802.11b-only
devices.

In AP mode, mac80211 was unconditionally using the lowest rate for
Beacon frames and similarly, with all rate control algorithms that use
rate_control_send_low(), the lowest rate ended up being used for all
broadcast frames (and all unicast frames that are sent before
association). Change this to take into account the basic rate
configuration in AP mode, i.e., use the lowest rate in the basic rate
set instead of the lowest supported rate when selecting the rate.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since I removed the master netdev, we've been
keeping internal queues only, and even before
that we never told the networking stack above
the virtual interfaces about congestion. This
means that packets are queued in mac80211 and
the upper layers never know, possibly leading
to memory exhaustion and other problems.

This patch makes all interfaces multiqueue and
uses ndo_select_queue to put the packets into
queues per AC. Additionally, when the driver
stops a queue, we now stop all corresponding
queues for the virtual interfaces as well.

The injection case will use VO by default for
non-data frames, and BE for data frames, but
downgrade any data frames according to ACM. It
needs to be fleshed out in the future to allow
chosing the queue/AC in radiotap.
Reported-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: stable@kernel.org [2.6.32]
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of always using netif_running(sdata->dev)
use ieee80211_sdata_running(sdata) now which is
just an inline containing netif_running() for now.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When mac80211 suspends it calls a driver's suspend callback
as a last step and after that the driver assumes no calls will
be made to it until we resume and its start callback is kicked.
If such calls are made, however, suspend can end up throwing
hardware in an unexpected state and making the device unusable
upon resume.

Fix this by preventing mac80211 to schedule dynamic_ps_disable_work
by checking for when mac80211 starts to suspend and starts
quiescing. Frames should be allowed to go through though as
that is part of the quiescing steps and we do not flush the
mac80211 workqueue since it was already done towards the
beginning of suspend cycle.

The other mac80211 issue will be hanled in the next patch.

For further details see refer to the thread:

http://marc.info/?t=126144866100001&r=1&w=2

Cc: stable@kernel.org
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

For bluetooth 3, we will most likely not have
a netdev for a virtual interface (sdata), so
prepare for that by reducing the reliance on
having a netdev. This patch moves the name
and address fields into the sdata struct and
uses them from there all over. Some work is
needed to keep them sync'ed, but that's not
a lot of work and in slow paths anyway.

In doing so, this also reduces the number of
pointer dereferences in many places, because
of things like sdata->dev->dev_addr becoming
sdata->vif.addr.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The station management currently uses the virtual
interface, but you cannot add the same station to
multiple virtual interfaces if you're communicating
with it in multiple ways.

This restriction should be lifted so that in the
future we can, for instance, support bluetooth 3
with an access point that mac80211 is already
associated to.

We can do that by requiring all sta_info_get users
to provide the virtual interface and making the RX
code aware that an address may match more than one
station struct. Thanks to the previous patches this
one isn't all that large and except for the RX and
TX status paths changes has low complexity.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Not including net/atm/

Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Right now all frames mac80211 hands to the driver
have the IEEE80211_TX_CTL_REQ_TX_STATUS flag set to
request TX status. This isn't really necessary, only
the injected frames need TX status (the latter for
hostapd) so move setting this flag.

The rate control algorithms also need TX status, but
they don't require it.

Also, rt2x00 uses that bit for its own purposes and
seems to require it being set for all frames, but
that can be fixed in rt2x00.

This doesn't really change anything for any drivers
but in the future drivers using hw-rate control may
opt to not report TX status for frames that don't
have the IEEE80211_TX_CTL_REQ_TX_STATUS flag set.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com> [rt2x00 bits]
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

It's very likely that not many devices will support
four-address mode in station or AP mode so introduce
capability bits for both modes, set them in mac80211
and check them when userspace tries to use the mode.
Also, keep track of 4addr in cfg80211 (wireless_dev)
and not in mac80211 any more. mac80211 can also be
improved for the VLAN case by not looking at the
4addr flag but maintaining the station pointer for
it correctly. However, keep track of use_4addr for
station mode in mac80211 to avoid all the derefs.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since the flags moved into skb->cb, there's no
longer a need to have the encrypt bool passed
into the function, anyone who requires it set
to 0 (false) can just set the flag directly.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some devices implement the entire rate control in
firmware in some way, like wl1271 or like iwlwifi
which does some things in software but not a lot.
Therefore generic software rate control is rather
useless for them and just adds avoidable overhead
to the transmit path.

It's fairly simple to let drivers indicate that
they do not need rate control, but they need to
fulfil a number of conditions that we encode in
WARN_ONs.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The netdev broadcast address cannot change from
all-ones so there's no need to use it; we can
instead hard-code it. Since we already have an
instance in tkip.c, which will be shared if it
is marked static const, doing this reduces text
size at no data/bss cost.

The real motivation for this is, of course, the
desire to get rid of almost all uses of netdevs
in mac80211 so that auditing their use becomes
easier.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If we move the rcu sections a little, there's
no need to touch the device refcount.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

BSSID is now set to the TA.
Signed-off-by: NRui Paulo <rpaulo@gmail.com>
Signed-off-by: NJavier Cardona <javier@cozybit.com>
Reviewed-by: NAndrey Yurovsky <andrey@cozybit.com>
Tested-by: NBrian Cavagnolo <brian@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In some situations it might be useful to run a network with an
Access Point and multiple clients, but with each client bridged
to a network behind it. For this to work, both the client and the
AP need to transmit 4-address frames, containing both source and
destination MAC addresses.
With this patch, you can configure a client to communicate using
only 4-address frames for data traffic.
On the AP side you can enable 4-address frames for individual
clients by isolating them in separate AP VLANs which are configured
in 4-address mode.
Such an AP VLAN will be limited to one client only, and this client
will be used as the destination for all traffic on its interface,
regardless of the destination MAC address in the packet headers.
The advantage of this mode compared to regular WDS mode is that it's
easier to configure and does not require a static list of peer MAC
addresses on any side.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some devices require that all frames to a station
are flushed when that station goes into powersave
mode before being able to send frames to that
station again when it wakes up or polls -- all in
order to avoid reordering and too many or too few
frames being sent to the station when it polls.

Normally, this is the case unless the station
goes to sleep and wakes up very quickly again.
But in that case, frames for it may be pending
on the hardware queues, and thus races could
happen in the case of multiple hardware queues
used for QoS/WMM. Normally this isn't a problem,
but with the iwlwifi mechanism we need to make
sure the race doesn't happen.

This makes mac80211 able to cope with the race
with driver help by a new WLAN_STA_PS_DRIVER
per-station flag that can be controlled by the
driver and tells mac80211 whether it can transmit
frames or not. This flag must be set according to
very specific rules outlined in the documentation
for the function that controls it.

When we buffer new frames for the station, we
normally set the TIM bit right away, but while
the driver has blocked transmission to that sta
we need to avoid that as well since we cannot
respond to the station if it wakes up due to the
TIM bit. Once the driver unblocks, we can set
the TIM bit.

Similarly, when the station just wakes up, we
need to wait until all other frames are flushed
before we can transmit frames to that station,
so the same applies here, we need to wait for
the driver to give the OK.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The multi-line code in this macro wasn't wrapped
in do {} while (0) so we cannot use it in an if()
branch safely in the future -- fix that.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When mac80211 is asked to buffer multicast frames
in AP mode, it will not set the flag indicating
that the frames should be sent after the DTIM
beacon for those frames buffered in software. Fix
this little inconsistency by always setting that
flag in the buffering code path.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Compared to ieee80211_beacon_get(), the new function
ieee80211_beacon_get_tim() returns information on the
location and length of the TIM IE, which some drivers
need in order to generate the TIM on the device. The
old function, ieee80211_beacon_get(), becomes a small
static inline wrapper around the new one to not break
all drivers.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In TX path it was assumed that dynamic power save works only if
IEEE80211_HW_PS_NULLFUNC_STACK is set. But is not the case, there are
devices which have nullfunc support in hardware but need mac80211
to handle dynamic power save timers, TI's wl1251 is one of them.

The fix is to not check for IEEE80211_HW_PS_NULLFUNC_STACK in
is_dynamic_ps_enabled(), instead check IEEE80211_HW_SUPPORTS_PS and
IEEE80211_HW_SUPPORTS_DYNAMIC_PS flags and act accordingly.

Tested with wl1251.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Refactor dynamic power save checks to a function of it's own for better
readibility. No functional changes.
Signed-off-by: NKalle Valo <kalle.valo@nokia.com>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When hostapd injects a frame, e.g. an authentication or association
response, mac80211 looks for a suitable access point virtual interface
to associate the frame with based on its source address. This makes it
possible e.g. to correctly assign sequence numbers to the frames.

A small typo in the ethernet address comparison statement caused a
failure to find a suitable ap interface. Sequence numbers on such
frames where therefore left unassigned causing some clients
(especially windows-based 11b/g clients) to reject them and fail to
authenticate or associate with the access point. This patch fixes the
typo in the address comparison statement.
Signed-off-by: NBjörn Smedman <bjorn.smedman@venatech.se>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When receiving data frames, we can send them only to
the interface they belong to based on transmitting
station (this doesn't work for probe requests). Also,
don't try to handle other frames for AP_VLAN at all
since those interface should only receive data.

Additionally, the transmit side must check that the
station we're sending a frame to is actually on the
interface we're transmitting on, and not transmit
packets to functions that live on other interfaces,
so validate that as well.

Another bug fix is needed in sta_info.c where in the
VLAN case when adding/removing stations we overwrite
the sdata variable we still need.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: stable@kernel.org
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Consider the following step-by step:
1. A STA authenticates and associates with the AP and exchanges
traffic.
2. The STA reports to the AP that it is going to PS state.
3. Some time later the STA device goes to the stand-by mode (not only
its wi-fi card, but the device itself) and drops the association state
without sending a disassociation frame.
4. The STA device wakes up and begins authentication with an
Auth frame as it hasn't been authenticated/associated previously.

At the step 4 the AP "remembers" the STA and considers it is still in
the PS state, so the AP buffers frames, which it has to send to the STA.
But the STA isn't actually in the PS state and so it neither checks
TIM bits nor reports to the AP that it isn't power saving.
Because of that authentication/[re]association fails.

To fix authentication/[re]association stage of this issue, Auth, Assoc
Resp and Reassoc Resp frames are transmitted disregarding of STA's power
saving state.

N.B. This patch doesn't fix further data frame exchange after
authentication/[re]association. A patch in hostapd is required to fix
that.
Signed-off-by: NIgor Perminov <igor.perminov@inbox.ru>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Mostly just simple conversions:
  * ray_cs had bogus return of NET_TX_LOCKED but driver
    was not using NETIF_F_LLTX
  * hostap and ipw2x00 had some code that returned value
    from a called function that also had to change to return netdev_tx_t
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Mesh frames that could not be immediately resolved were queued with a NULL
info->control.vif.  This patch moves the call to mesh_nexthop_lookup closer to
the point where it is handed over to ieee80211_tx().  This ensures that the
unresolved frames are ready to be sent once the path is resolved.
Signed-off-by: NJavier Cardona <javier@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>