linux-toradex.git/include/linux/nl80211.h, branch v2.6.35.3

cfg80211/mac80211: better channel handling

2010-05-07T18:55:50+00:00

Currently (all tested with hwsim) you can do stupid
things like setting up an AP on a certain channel,
then adding another virtual interface and making
that associate on another channel -- this will make
the beaconing to move channel but obviously without
the necessary IEs data update.

In order to improve this situation, first make the
configuration APIs (cfg80211 and nl80211) aware of
multi-channel operation -- we'll eventually need
that in the future anyway. There's one userland API
change and one API addition. The API change is that
now SET_WIPHY must be called with virtual interface
index rather than only wiphy index in order to take
effect for that interface -- luckily all current
users (hostapd) do that. For monitor interfaces, the
old setting is preserved, but monitors are always
slaved to other devices anyway so no guarantees.

The second userland API change is the introduction
of a per virtual interface SET_CHANNEL command, that
hostapd should use going forward to make it easier
to understand what's going on (it can automatically
detect a kernel with this command).

Other than mac80211, no existing cfg80211 drivers
are affected by this change because they only allow
a single virtual interface.

mac80211, however, now needs to be aware that the
channel settings are per interface now, and needs
to disallow (for now) real multi-channel operation,
which is another important part of this patch.

One of the immediate benefits is that you can now
start hostapd to operate on a hardware that already
has a connection on another virtual interface, as
long as you specify the same channel.

Note that two things are left unhandled (this is an
improvement -- not a complete fix):

 * different HT/no-HT modes

   currently you could start an HT AP and then
   connect to a non-HT network on the same channel
   which would configure the hardware for no HT;
   that can be fixed fairly easily

 * CSA

   An AP we're connected to on a virtual interface
   might indicate switching channels, and in that
   case we would follow it, regardless of how many
   other interfaces are operating; this requires
   more effort to fix but is pretty rare after all

Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

cfg80211: add ap isolation support

2010-04-27T20:09:21+00:00

This is used to configure APs to not bridge traffic between connected stations.

Signed-off-by: Felix Fietkau 
Signed-off-by: John W. Linville

cfg80211: Add local-state-change-only auth/deauth/disassoc

2010-04-07T18:37:56+00:00

cfg80211 is quite strict on allowing authentication and association
commands only in certain states. In order to meet these requirements,
user space applications may need to clear authentication or
association state in some cases. Currently, this can be done with
deauth/disassoc command, but that ends up sending out Deauthentication
or Disassociation frame unnecessarily. Add a new nl80211 attribute to
allow this sending of the frame be skipped, but with all other
deauth/disassoc operations being completed.

Similar state change is also needed for IEEE 802.11r FT protocol in
the FT-over-DS case which does not use Authentication frame exchange
in a transition to another BSS. For this to work with cfg80211, an
authentication entry needs to be created for the target BSS without
sending out an Authentication frame. The nl80211 authentication
command can be used for this purpose, too, with the new attribute to
indicate that the command is only for changing local state. This
enables wpa_supplicant to complete FT-over-DS transition successfully.

Signed-off-by: Jouni Malinen 
Signed-off-by: John W. Linville

cfg80211: Improve connection quality maintenance docs in nl80211.h

2010-03-24T20:04:33+00:00

In nl80211.h, be a little more elaborate in the docs for the definitions
NL80211_ATTR_CQM_RSSI_THOLD and NL80211_ATTR_CQM_RSSI_HYST.

Reported-by: Luis R. Rodriguez 
Signed-off-by: Juuso Oikarinen 
Signed-off-by: John W. Linville

cfg80211: Add connection quality monitoring support to nl80211

2010-03-24T20:02:37+00:00

Add support for basic configuration of a connection quality monitoring to the
nl80211 interface, and basic support for notifying about triggered monitoring
events.

Via this interface a user-space connection manager may configure and receive
pre-warning events of deteriorating WLAN connection quality, and start
preparing for roaming in advance, before the connection is already lost.

An example usage of such a trigger is starting scanning for nearby AP's in
an attempt to find one with better connection quality, and associate to it
before the connection characteristics of the existing connection become too bad
or the association is even lost, leading in a prolonged delay in connectivity.

The interface currently supports only RSSI, but it could be later extended
to include other parameters, such as signal-to-noise ratio, if need for that
arises.

Signed-off-by: Juuso Oikarinen 
Reviewed-by: Johannes Berg 
Signed-off-by: John W. Linville

nl80211: add power save commands

2010-02-19T20:52:40+00:00

The most needed command from nl80211, which Wireless Extensions had,
is support for power save mode. Add a simple command to make it possible
to enable and disable power save via nl80211.

I was also planning about extending the interface, for example adding the
timeout value, but after thinking more about this I decided not to do it.
Basically there were three reasons:

Firstly, the parameters for power save are very much hardware dependent.
Trying to find a unified interface which would work with all hardware, and
still make sense to users, will be very difficult.

Secondly, IEEE 802.11 power save implementation in Linux is still in state
of flux. We have a long way to still to go and there is no way to predict
what kind of implementation we will have after few years. And because we
need to support nl80211 interface a long time, practically forever, adding
now parameters to nl80211 might create maintenance problems later on.

Third issue are the users. Power save parameters are mostly used for
debugging, so debugfs is better, more flexible, interface for this.
For example, wpa_supplicant currently doesn't configure anything related
to power save mode. It's better to strive that kernel can automatically
optimise the power save parameters, like with help of pm qos network
and other traffic parameters.

Later on, when we have better understanding of power save, we can extend
this command with more features, if there's a need for that.

Signed-off-by: Kalle Valo 
Signed-off-by: John W. Linville

cfg80211/mac80211: allow registering for and sending action frames

2010-02-15T21:14:15+00:00

This implements a new command to register for action frames
that userspace wants to handle instead of the in-kernel
rejection. It is then responsible for rejecting ones that
it decided not to handle. There is no unregistration, but
the socket can be closed for that.

Frames that are not registered for will not be forwarded
to userspace and will be rejected by the kernel, the
cfg80211 API helps implementing that.

Additionally, this patch adds a new command that allows
doing action frame transmission from userspace. It can be
used either to exchange action frames on the current
operational channel (e.g., with the AP with which we are
currently associated) or to exchange off-channel Public
Action frames with the remain-on-channel command.

Signed-off-by: Jouni Malinen 
Signed-off-by: Johannes Berg 
Signed-off-by: John W. Linville

cfg80211: Store IEs from both Beacon and Probe Response frames

2010-01-12T18:51:28+00:00

Store information elements from Beacon and Probe Response frames in
separate buffers to allow both sets to be made available through
nl80211. This allows user space applications to get access to IEs from
Beacon frames even if we have received Probe Response frames from the
BSS. Previously, the IEs from Probe Response frames would have
overridden the IEs from Beacon frames.

This feature is of somewhat limited use since most protocols include
the same (or extended) information in Probe Response frames. However,
there are couple of exceptions where the IEs from Beacon frames could
be of some use: TIM IE is only included in Beacon frames (and it would
be needed to figure out the DTIM period used in the BSS) and at least
some implementations of Wireless Provisioning Services seem to include
the full IE only in Beacon frames).

The new BSS attribute for scan results is added to allow both the IE
sets to be delivered. This is done in a way that maintains the
previously used behavior for applications that are not aware of the
new NL80211_BSS_BEACON_IES attribute.

Signed-off-by: Jouni Malinen 
Acked-by: Johannes Berg 
Signed-off-by: John W. Linville

nl80211: New command for setting TX rate mask for rate control

2010-01-12T18:51:23+00:00

Add a new NL80211_CMD_SET_TX_BITRATE_MASK command and related
attributes to provide support for setting TX rate mask for rate
control. This uses the existing cfg80211 set_bitrate_mask operation
that was previously used only with WEXT compat code (SIOCSIWRATE). The
nl80211 command allows more generic configuration of allowed rates as
a mask instead of fixed/max rate.

Signed-off-by: Jouni Malinen 
Acked-by: Johannes Berg 
Signed-off-by: John W. Linville

nl80211: Add new WIPHY attribute COVERAGE_CLASS

2010-01-12T18:49:17+00:00

The new attribute NL80211_ATTR_WIPHY_COVERAGE_CLASS sets IEEE 802.11
Coverage Class, which depends on maximum distance of nodes in a
wireless network. It's required for long distance links (more than a few
hundred meters).

The attribute is now ignored by two non-mac80211 drivers, rndis and
iwmc3200wifi, together with WIPHY_PARAM_RETRY_SHORT and
WIPHY_PARAM_RETRY_LONG. If it turns out to be a problem, we could split
set_wiphy_params callback or add new capability bits.

Signed-off-by: Lukas Turek <8an@praha12.net>
Signed-off-by: John W. Linville