802.11-2012 13.3.1 implicitly limits the mesh local link
ID range to that of AID, since for mesh PS the local link
ID must be indicated in the TIM IE, which only holds
IEEE80211_MAX_AID bits.

Also the code was allowing a local link ID of 0, but this
is not correct since that TIM bit is used for indicating
buffered mcast frames.

Generate a random, unique, link ID from 1 - 2007, and drop
a modulo conversion for the local link ID, but keep it for
the peer link ID in case he chose something > MAX_AID.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
[fix some indentation, squash llid assignment]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If we store the peer link ID right after initializing a
new neighbor, there is no need to do it later in the
peering FSM.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

All other paths return an error code, do the same here.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The ignore_plink_timer flag is set when doing mod_timer() if
the timer was not previously active.  This is to avoid executing
the timeout if del_timer() was subsequently called.  However,
del_timer() only happens if we are moving to ESTAB state or
get a close frame while in HOLDING.

We cannot leave HOLDING and re-enter ESTAB unless we receive a
close frame (in which case ignore_plink_timer is already set) or
if the timeout expires, so there actually isn't a case where
this is needed on mod_timer().
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The matches_local check can just be done when looking at the
individual action types.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Use C instead of cpp for type checking.  Also swap the arguments
into the usual sdata -> sta order.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The initial frame checks differ depending on whether this is
a new peer or not, but they were all intermixed with sta checks
as necessary.  Group them together so the two cases are clearer.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Reject and accepted close events always put the host in the
holding state and compute a reason code based only on the
current state.  Likewise on establish we always do the same
setup.  Put these in functions to save some duplicated code.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Rather than unlock at the end of each case, do it once after
all is said and done.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Do all frame transfers in one place at the end of the
big switch statements.  sta->plid and sta->reason can
be passed in any case, since they are only used for
the frames that need them.  Remove assignments to locals
for values already stored in the sta structure.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

According to IEEE 802.11-2012 (8.4.2.104), no peering
management element exists with length 7. This code is checking
to see if llid is present to ignore close frames with different
llid, which would be IEs with length 8.
Signed-off-by: NBob Copeland <bob@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This patch fixes errors in the mesh powersave logic which
cause that remote peers do not get peer power mode change
notifications and mesh peer service periods (MPSPs) got
stuck.

When closing a peer link, set the (now invalid) peer-specific
power mode to 'unknown'.

Avoid overhead when local power mode is unchanged.

Reliably clear MPSP flags on peering status update.

Avoid MPSP flags getting stuck by not requesting a further
MPSP ownership if we already are an MPSP owner.
Signed-off-by: NMarco Porsch <marco@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The various components accessing the bitrates table must use consider
the used channel bandwidth to select only available rates or calculate
the bitrate correctly.

There are some rates in reduced bandwidth modes which can't be
represented as multiples of 500kbps, like 2.25 MBit/s in 5 MHz mode. The
standard suggests to round up to the next multiple of 500kbps, just do
that in mac80211 as well.
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
[make rate unsigned in ieee80211_add_tx_radiotap_header(), squash fix]
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>

This is a collection of minor fixes:
 * don't allow HT IEs in IBSS for 5/10 MHz
 * don't allow HT IEs in Mesh for 5/10 MHz
 * don't downgrade from/to 5 and 10 MHz channels
 * don't try HT rates for 5 and 10 MHz channels when selecting rates
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The patch "cfg80211/mac80211: use cfg80211 wdev mutex in
mac80211" introduced several deadlocks by converting the
ifmsh->mtx to wdev->mtx. Solve these by:

1. drop the cancel_work_sync() in ieee80211_stop_mesh().
   Instead make the mesh work conditional on whether the mesh
   is running or not.
2. lock the mesh work with sdata_lock() to protect beacon
   updates and prevent races with wdev->mesh_id_len or
   cfg80211.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Using separate locks in cfg80211 and mac80211 has always
caused issues, for example having to unlock in places in
mac80211 to call cfg80211, which even needed a framework
to make cfg80211 calls after some functions returned etc.

Additionally, I suspect some issues people have reported
with the cfg80211 state getting confused could be due to
such issues, when cfg80211 is asking mac80211 to change
state but mac80211 is in the process of telling cfg80211
that the state changed (in another way.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

VHT introduces multiple IEs that need to be parsed for a
wide bandwidth channel switch. Two are (currently) needed
in mac80211:
 * wide bandwidth channel switch element
 * channel switch wrapper element

The former is contained in the latter for beacons and probe
responses, but not for the spectrum management action frames
so the IE parser needs a new argument to differentiate them.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The patch "mac80211: stringify mesh peering events" missed
an opportunity to print the peering state as a string.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There is a corner case which wasn't being covered:
userspace may authenticate and allocate stations,
but still leave the peering up to the kernel.

Initialize the peering timer if the MPM is not in
userspace, in a path which is taken by both the kernel and
userspace when allocating stations.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Earlier mac80211 would check whether some kind of mesh
security was enabled, when the real question was "is the
MPM in userspace"?
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Remove not used any longer suspend/resume code.
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Convert mesh peering events into strings and make the
debug output a little easier to read. Also stop printing
the llid and plid since these don't change across peering
states and are random numbers anyway so they just amount
to noise.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

ieee80211_ht_cap_ie_to_sta_ht_cap() will clean up the
ht_supported flag and station bandwidth field for us
if the peer beacon doesn't have an HT capability element
(is operating as non-HT).

Also, we don't really need a special station ch_width
member to track the station operating mode any more so use
sta.bandwidth instead.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's various code with strange indentation,
questionable loop and locking constructs, etc.

The bigger change is moving the "sdata" argument
to the first argument of all functions, like all
other mac80211 functions that have one.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Previously, the entire mesh beacon would be generated each
time the beacon timer fired. Instead generate a beacon
head and tail (so the TIM can easily be inserted when mesh
power save is on) when starting a mesh or the MBSS
parameters change.

Also add a mutex for protecting beacon updates and
preventing leaks.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

For VHT, many more bandwidth changes are possible. As a first
step, stop toggling the IEEE80211_HT_CAP_SUP_WIDTH_20_40 flag
in the HT capabilities and instead introduce a bandwidth field
indicating the currently usable bandwidth to transmit to the
station. Of course, make all drivers use it.

To achieve this, make ieee80211_ht_cap_ie_to_sta_ht_cap() get
the station as an argument, rather than the new capabilities,
so it can set up the new bandwidth field.

If the station is a VHT station and VHT bandwidth is in use,
also set the bandwidth accordingly.

Doing this allows us to get rid of the supports_40mhz flag as
the HT capabilities now reflect the true capability instead of
the current setting.

While at it, also fix ieee80211_ht_cap_ie_to_sta_ht_cap() to not
ignore HT cap overrides when MCS TX isn't supported (not that it
really happens...)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

A few mesh utility functions will call
ieee80211_bss_info_change_notify(), and then the caller
might notify the driver of the same change again. Avoid
this redundancy by propagating the BSS changes and
generally calling bss_info_change_notify() once per
change.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The patch "mac80211: clean up mesh sta allocation warning"
moved some mesh initialization into a path which is only
called when the kernel handles peering. This causes a hang
when mac80211 tries to clean up a userspace-allocated
station entry and delete a timer which has never been
initialized.

To avoid this, only do any mesh sta peering teardown if
the kernel is actually handling it.

The same is true when quiescing before suspend.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since mesh_plink_quiesce() would unconditionally delete
the plink timer, and the timer initialization was recently
moved into the mesh code path, suspending with a non-mesh
interface now causes a crash. Fix this by only deleting
the plink timer for mesh interfaces.
Reported-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Tested-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Add routines to
- maintain a PS mode for each peer and a non-peer PS mode
- indicate own PS mode in transmitted frames
- track neighbor STAs power modes
- buffer frames when neighbors are in PS mode
- add TIM and Awake Window IE to beacons
- release frames in Mesh Peer Service Periods

Add local_pm to sta_info to represent the link-specific power
mode at this station towards the remote station. When a peer
link is established, use the default power mode stored in mesh
config. Update the PS status if the peering status of a neighbor
changes.
Maintain a mesh power mode for non-peer mesh STAs. Set the
non-peer power mode to active mode during peering. Authenticated
mesh peering is currently not working when either node is
configured to be in power save mode.

Indicate the current power mode in transmitted frames. Use QoS
Nulls to indicate mesh power mode transitions.
For performance reasons, calls to the function setting the frame
flags are placed in HWMP routing routines, as there the STA
pointer is already available.

Add peer_pm to sta_info to represent the peer's link-specific
power mode towards the local station. Add nonpeer_pm to
represent the peer's power mode towards all non-peer stations.
Track power modes based on received frames.

Add the ps_data structure to ieee80211_if_mesh (for TIM map, PS
neighbor counter and group-addressed frame buffer).

Set WLAN_STA_PS flag for STA in PS mode to use the unicast frame
buffering routines in the tx path. Update num_sta_ps to buffer
and release group-addressed frames after DTIM beacons.

Announce the awake window duration in beacons if in light or
deep sleep mode towards any peer or non-peer. Create a TIM IE
similarly to AP mode and add it to mesh beacons. Parse received
Awake Window IEs and check TIM IEs for buffered frames.

Release frames towards peers in mesh Peer Service Periods. Use
the corresponding trigger frames and monitor the MPSP status.
Append a QoS Null as trigger frame if neccessary to properly end
the MPSP. Currently, in HT channels MPSPs behave imperfectly and
show large delay spikes and frame losses.
Signed-off-by: NMarco Porsch <marco@cozybit.com>
Signed-off-by: NIvan Bezyazychnyy <ivan.bezyazychnyy@gmail.com>
Signed-off-by: NMike Krinkin <krinkin.m.u@gmail.com>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The standard mandates mesh STAs to set the ERP Short Slot
Time capability info bit in beacons to 0. Even though this
is their way of disallowing short slot time for mesh STAs,
there should be no harm in enabling it if we determine all
STAs in the current MBSS support ERP rates.

Increases throughput about 20% for legacy rates when
enabled.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Before "mac80211: clean up mesh sta allocation warning"
was applied, mesh_sta_info_get() was reshuffled to please
sparse. As a result we neglect to initialize newly created
STAs. Fix this.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

An existing mesh station entry may change its rate
capabilities, so call rate_control_rate_update() to notify
the rate control.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
[fix compilation]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This refactoring fixes a "scheduling while atomic" warning
when allocating a mesh station entry while holding the RCU
read lock. Fix this by creating a new function
mesh_sta_info_get(), which correctly handles the locking
and returns under RCU.

Also move some unnecessarily #ifdefed mesh station init
code from sta_info_alloc() to __mesh_sta_info_alloc().
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
[change code flow to make sparse happy]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The established peer link count is indicated in mesh beacons and
used for other internal tasks. Previously it was not updated when
authenticated peering is performed in userspace.
Signed-off-by: NMarco Porsch <marco@cozybit.com>
Acked-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This fixes some unintended resets of the rate control statistics
when minstrel_ht is used resulting in non-optimal throughput on mesh
links.
Tested-by: NEmanuel Taube <emanuel.taube@gmail.com>
Signed-off-by: NHelmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>