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: Johannes Berg <johannes.berg@intel.com>
Some of the chandef checking that we do in cfg80211
to check if a channel is supported or not is also
needed in mac80211, so rework that a bit and export
the functions that are needed.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Change nl80211 to support specifying a VHT (or HT)
using the control channel frequency (as before) and
new attributes for the channel width and first and
second center frequency. The old channel type is of
course still supported for HT.
Also change the cfg80211 channel definition struct
to support these by adding the relevant fields to
it (and removing the _type field.)
This also adds new helper functions:
- cfg80211_chandef_create to create a channel def
struct given the control channel and channel type,
- cfg80211_chandef_identical to check if two channel
definitions are identical
- cfg80211_chandef_compatible to check if the given
channel definitions are compatible, and return the
wider of the two
This isn't entirely complete, but that doesn't matter
until we have a driver using it. In particular, it's
missing
- regulatory checks on the usable bandwidth (if that
even makes sense)
- regulatory TX power (database can't deal with it)
- a proper channel compatibility calculation for the
new channel types
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of passing a channel pointer and channel type
to all functions and driver methods, pass a new channel
definition struct. Right now, this struct contains just
the control channel and channel type, but for VHT this
will change.
Also, add a small inline cfg80211_get_chandef_type() so
that drivers don't need to use the _type field of the
new structure all the time, which will change.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As mwifiex (and mac80211 in the software case) are the
only drivers actually implementing remain-on-channel
with channel type, userspace can't be relying on it.
This is the case, as it's used only for P2P operations
right now.
Rather than adding a flag to tell userspace whether or
not it can actually rely on it, simplify all the code
by removing the ability to use different channel types.
Leave only the validation of the attribute, so that if
we extend it again later (with the needed capability
flag), it can't break userspace sending invalid data.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The commit:
commit 5e760230e4
Author: Johannes Berg <johannes.berg@intel.com>
Date: Fri Nov 4 11:18:17 2011 +0100
cfg80211: allow registering to beacons
allowed only a single process to register for beacon events
per wiphy. This breaks cases where a user may want two or
more VIFs on a wiphy and run a seperate hostapd process on
each vif.
This patch allows multiple beacon listeners, fixing the
regression.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
SAE extends Authentication frames with fields that are not information
elements. NL80211_ATTR_IE is not suitable for these, so introduce a new
attribute that can be used to specify the fields needed for SAE in
station mode.
Signed-off-by: Jouni Malinen <j@w1.fi>
[change to verify that SAE is only used with authenticate command]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
It is a frequent mistake to confuse the netlink port identifier with a
process identifier. Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.
I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.
I have successfully built an allyesconfig kernel with this change.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
libertas currently calls cfg80211_disconnected() when it is being
brought down. This causes an event to be allocated, but since the
wdev is already removed from the rdev by the time that the event
processing work executes, the event is never processed or freed.
http://article.gmane.org/gmane.linux.kernel.wireless.general/95666
Fix this leak, and other possible situations, by processing the event
queue when a device is being unregistered. Thanks to Johannes Berg for
the suggestion.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Cc: stable@vger.kernel.org
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Revert commit b78e8ceac2
("cfg80211: track monitor channel") and remove the
set_monitor_enabled() callback.
Due to the tracking happening in NETDEV_PRE_UP, it had
introduced bugs because the monitor interface callback
would be called before the device was started. It looks
like there's no way to fix this, and using NETDEV_PRE_UP
is broken anyway (since there's no NETDEV_UP_FAIL), so
remove all that code, track interfaces in NETDEV_UP and
also stop tracking the monitor channel in cfg80211.
This mostly reverts to before the tracking, except that
we keep the interface count tracking so that setting the
monitor channel can be rejected properly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
To call cfg80211_get_chan_state() we need to lock
the wdev, so we need to lock the wdev_iter mutex
in cfg80211_can_use_iftype_chan(). This needs to
use nested locking for lockdep.
Also, cfg80211_get_chan_state() doesn't actually
use the rdev, so remove that completely including
the lock assertion that isn't needed.
Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The management frame and remain-on-channel APIs will be
needed in the P2P device abstraction, so move them over
to the new wdev-based APIs. Userspace can still use both
the interface index and wdev identifier for them so it's
backward compatible, but for the P2P Device wdev it will
be able to use the wdev identifier only.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to support a P2P device abstraction and
Bluetooth high-speed AMPs, we need to have a way
to identify virtual interfaces that don't have a
netdev associated.
Do this by adding a NL80211_ATTR_WDEV attribute
to identify a wdev which may or may not also be
a netdev.
To simplify things, use a 64-bit value with the
high 32 bits being the wiphy index for this new
wdev identifier in the nl80211 API.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Michal's monitor channel tracking introduce a locking problem
as it locked the rdev lock inside the netdev notifier which
isn't allowed as we might already hold it if we get there by
removing an interface that is up.
Fix this by relying only on the RTNL to protect the interface
counters, the RTNL is always held in these code paths anyway.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
.connect cannot be handled since the driver scans
and connects on its own. It is up to the driver
then to refuse a connection (with -EBUSY for
example).
Non-fixed channel IBSSes always take a single
channel resource. For example two non-fixed
channel IBSSes always take up 2
num_different_channels, even if they operate on
the same channel at a given point of time.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Make it even more obvious we support single
monitor channel. This will allow us to remove
.get_channel.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Implements .set_monitor_enabled(wiphy, enabled).
Notifies driver upon change of interface layout.
If only monitor interfaces become present it is
called with 2nd argument being true. If
non-monitor interface appears then 2nd argument
is false. Driver is notified only upon change.
This makes it more obvious about the fact that
cfg80211 supports single monitor channel. Once we
implement multi-channel we don't want to allow
setting monitor channel while other interface
types are running. Otherwise it would be ambiguous
once we start considering num_different_channels.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Helper function for finding out which channel is
used by a given interface.
An exclusive channel can be used only by a single
interface. This is mainly for non-fixed channel
IBSS handling.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This functionality will be reused when interface
is going down. Avoids code duplication. Also adds
missing wdev locking.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Now that we've removed all uses of the set_channel
API except for the monitor channel and in libertas,
clarify this. Split the libertas mesh use into a
new libertas_set_mesh_channel() operation, just to
keep backward compatibility, and rename the normal
set_channel() to set_monitor_channel().
Also describe the desired set_monitor_channel()
semantics more clearly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Just like the AP mode patch, instead of setting
the channel and then joining the mesh network,
provide the channel to join the network on to
the join_mesh() function.
Like in AP mode, you can also give the channel
to the join-mesh nl80211 command now.
Unlike AP mode, it picks a default channel if
none was given.
As libertas uses mesh mode interfaces but has
no join_mesh callback and we can't simply break
it, keep some compatibility code for that case
and configure the channel directly for it.
In the non-libertas case, where we store the
channel until join, allow setting it while the
interface is down.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
cfg80211_calculate_bitrate() is defined in the external
header file cfg80211.h now, so no need to keep it in
the internal one as well.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is needed by mac80211 to keep a reference
to a BSS alive for the auth process. Remove the
old version of cfg80211_ref_bss() since it's
not actually used.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
To track authenticated state seems to have been
a design mistake in cfg80211. It is possible to
have out of band authentication (FT), tracking
multiple authentications caused more problems
than it ever helped, and the implementation in
mac80211 is too complex.
Remove all this complexity, and let userspace
do whatever it wants to, mac80211 can deal with
that just fine. Association is still tracked of
course, but authentication no longer is. Local
auth state changes are thus no longer of value,
so ignore them completely.
This will also help implement SAE -- asking the
driver to do an authentication is now almost
equivalent to sending an authentication frame,
with the exception of shared key authentication
which is still handled completely.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
It is quite possible to run into a race in bss timeout where
the drivers see the bss entry just before notifying cfg80211
of a roaming event but it got timed out by the time rdev->event_work
got scehduled from cfg80211_wq. This would result in the following
WARN-ON() along with the failure to notify the user space of
the roaming. The other situation which is happening with ath6kl
that runs into issue is when the driver reports roam to same AP
event where the AP bss entry already got expired. To fix this,
move cfg80211_get_bss() from __cfg80211_roamed() to cfg80211_roamed().
[158645.538384] WARNING: at net/wireless/sme.c:586
__cfg80211_roamed+0xc2/0x1b1()
[158645.538810] Call Trace:
[158645.538838] [<c1033527>] warn_slowpath_common+0x65/0x7a
[158645.538917] [<c14cfacf>] ? __cfg80211_roamed+0xc2/0x1b1
[158645.538946] [<c103354b>] warn_slowpath_null+0xf/0x13
[158645.539055] [<c14cfacf>] __cfg80211_roamed+0xc2/0x1b1
[158645.539086] [<c14beb5b>] cfg80211_process_rdev_events+0x153/0x1cc
[158645.539166] [<c14bd57b>] cfg80211_event_work+0x26/0x36
[158645.539195] [<c10482ae>] process_one_work+0x219/0x38b
[158645.539273] [<c14bd555>] ? wiphy_new+0x419/0x419
[158645.539301] [<c10486cb>] worker_thread+0xf6/0x1bf
[158645.539379] [<c10485d5>] ? rescuer_thread+0x1b5/0x1b5
[158645.539407] [<c104b3e2>] kthread+0x62/0x67
[158645.539484] [<c104b380>] ? __init_kthread_worker+0x42/0x42
[158645.539514] [<c151309a>] kernel_thread_helper+0x6/0xd
Reported-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This allows users to disable features such as HT, HT40,
and to modify the MCS, AMPDU, and AMSDU settings for
drivers that support it.
The MCS, AMPDU, and AMSDU features that may be disabled are
are reported in the phy-info netlink message as a mask.
Attemping to disable features that are not supported will
take no affect, but will not return errors. This is to aid
backwards compatibility in user-space apps that may not be
clever enough to deal with parsing the the capabilities mask.
This patch only enables the infrastructure. An additional
patch will enable the feature in mac80211.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For probe responses it can be useful to not wait for ACK to
avoid retransmissions if the station that sent the probe is
already on the next channel, so allow userspace to request
not caring about the ACK with a new nl80211 flag.
Since mac80211 needs to be updated for the new function
prototype anyway implement it right away -- it's just a
few lines of code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add the ability to register to received beacon frames
to allow implementing OLBC logic in userspace. The
registration is per wiphy since there's no point in
receiving the same frame multiple times.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add a new nl80211 attribute to specify whether to send the management
frames in CCK rate or not. As of now the wpa_supplicant is disabling
CCK rate at P2P init itself. So this patch helps to send P2P probe
request/probe response/action frames being sent at non CCK rate in 2GHz
without disabling 11b rates.
This attribute is used with NL80211_CMD_TRIGGER_SCAN and
NL80211_CMD_FRAME commands to disable CCK rate for management frame
transmission.
Cc: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Instead of using a hardcoded list of cipher suites in nl80211.c, use a
shared function in util.c to verify that the driver advertises support
for the specified cipher. This provides more accurate validation of the
values and allows vendor-specific cipher suites to be added in drivers.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The function wiphy_update_regulatory() uses the static variable
last_request and thus needs to be called with reg_mutex held.
This is the case for all users in reg.c, but the function was
exported for use by wiphy_register(), from where it is called
without the lock being held.
Fix this by making wiphy_update_regulatory() private and introducing
regulatory_update() as a wrapper that acquires and holds the lock.
Signed-off-by: Sven Neumann <s.neumann@raumfeld.com>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Luis R. Rodriguez <mcgrof@gmail.com>
Cc: Daniel Mack <daniel@zonque.org>
Cc: linux-wireless@vger.kernel.org
Acked-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some P2P scans are not allowed to advertise
11b rates, but that is a rather special case
so instead of having that, allow userspace
to request the rate sets (per band) that are
advertised in scan probe request frames.
Since it's needed in two places now, factor
out some common code parsing a rate array.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
There was a deadlock when rfkill-blocking a wireless interface,
because we were locking the rdev mutex on NETDEV_GOING_DOWN to stop
sched_scans that were eventually running. The rfkill block code was
already holding a mutex under rdev:
kernel: =======================================================
kernel: [ INFO: possible circular locking dependency detected ]
kernel: 3.0.0-rc1-00049-g1fa7b6a #57
kernel: -------------------------------------------------------
kernel: kworker/0:1/4525 is trying to acquire lock:
kernel: (&rdev->mtx){+.+.+.}, at: [<ffffffff8164c831>] cfg80211_netdev_notifier_call+0x131/0x5b0
kernel:
kernel: but task is already holding lock:
kernel: (&rdev->devlist_mtx){+.+.+.}, at: [<ffffffff8164dcef>] cfg80211_rfkill_set_block+0x4f/0xa0
kernel:
kernel: which lock already depends on the new lock.
To fix this, add a new mutex specifically for sched_scan, to protect
the sched_scan_req element in the rdev struct, instead of using the
global rdev mutex.
Reported-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
cfg80211 scan code adds separate BSS entries if the same BSS shows up
on multiple channels. However, sme implementation does not use the
frequency when fetching the BSS entry. Fix this by adding channel
information to cfg80211_roamed() and include it in cfg80211_get_bss()
calls.
Please note that drivers using cfg80211_roamed() need to be modified to
fully implement this fix. This commit includes only minimal changes to
avoid compilation issues; it maintains the old (broken) behavior for
most drivers. ath6kl was the only one that I could test, so I updated
it to provide the operating frequency in the roamed event.
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add the ability to advertise interface combinations in nl80211.
This allows the driver to indicate what the combinations are
that it supports. "Combinations" of just a single interface are
implicit, as previously. Note that cfg80211 will enforce that
the restrictions are met, but not for all drivers yet (once all
drivers are updated, we can remove the flag and enforce for all).
When no combinations are actually supported, an empty list will
be exported so that userspace can know if the kernel exported
this info or not (although it isn't clear to me what tools using
the info should do if the kernel didn't export it).
Since some interface types are purely virtual/software and don't
fit the restrictions, those are exposed in a new list of pure SW
types, not subject to restrictions. This mainly exists to handle
AP-VLAN and monitor interfaces in mac80211.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When sched_scan_stopped was called by the driver, mac80211 calls
cfg80211, which in turn was calling mac80211 back with a flag
"driver_initiated". This flag was used so that mac80211 would do the
necessary cleanup but would not call the driver. This was enough to
prevent the bounce back between the driver and mac80211, but not
between mac80211 and cfg80211.
To fix this, we now do the cleanup in mac80211 before calling
cfg80211. To help with locking issues, the workqueue was moved from
cfg80211 to mac80211.
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Multiple virtual AP interfaces can currently try
to use different beacon intervals, but that just
leads to problems since it won't actually be done
that way by drivers. Return an error in this case
to make sure it won't be done wrong.
Also, ignore attempts to change the DTIM period
or beacon interval during the lifetime of the BSS.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Implement new functionality for scheduled scan offload. With this feature we
can scan automatically at certain intervals.
The idea is that the hardware can perform scan automatically and filter on
desired results without waking up the host unnecessarily.
Add NL80211_CMD_START_SCHED_SCAN and NL80211_CMD_STOP_SCHED_SCAN
commands to the nl80211 interface. When results are available they are
reported by NL80211_CMD_SCHED_SCAN_RESULTS events. The userspace is
informed when the scheduled scan has stopped with a
NL80211_CMD_SCHED_SCAN_STOPPED event, which can be triggered either by
the driver or by a call to NL80211_CMD_STOP_SCHED_SCAN.
Signed-off-by: Luciano Coelho <coelho@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This is based on (but now quite far from) the
original work from Luis and Eliad. Add support
for configuring WoWLAN triggers, and getting
the configuration out again. Changes from the
original patchset are too numerous to list,
but one important change needs highlighting:
the suspend() callback is passed NULL for the
trigger configuration if userspace has not
configured WoWLAN at all.
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Userspace will now be allowed to toggle between the default path
selection algorithm (HWMP, implemented in the kernel), and a vendor
specific alternative. Also in the same patch, allow userspace to add
information elements to mesh beacons. This is accordance with the
Extensible Path Selection Framework specified in version 7.0 of the
802.11s draft.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Instead of tying mesh activity to interface up,
add join and leave commands for mesh. Since we
must be backward compatible, let cfg80211 handle
joining a mesh if a mesh ID was pre-configured
when the device goes up.
Note that this therefore must modify mac80211 as
well since mac80211 needs to lose the logic to
start the mesh on interface up.
We now allow querying mesh parameters before the
mesh is connected, which simply returns defaults.
Setting them (internally renamed to "update") is
only allowed while connected. Specify them with
the new mesh join command instead where needed.
In mac80211, beaconing must now also follow the
mesh enabled/not enabled state, which is done
by testing the mesh ID.
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
With p2p, it is sometimes necessary to transmit
a frame (typically an action frame) on another
channel than the current channel. Enable this
through the CMD_FRAME API, and allow it to wait
for a response. A new command allows that wait
to be aborted.
However, allow userspace to specify whether or
not it wants to allow off-channel TX, it may
actually want to use the same channel only.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This adds API to allow adding per-station GTKs,
updates mac80211 to support it, and also allows
drivers to remove a key from hwaccel again when
this may be necessary due to multiple GTKs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Change "return (EXPR);" to "return EXPR;"
return is not a function, parentheses are not required.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of using a WARN_ON(!mutex_is_locked())
use lockdep_assert_held() which compiles away
completely when lockdep isn't enabled, and
also is a more accurate assertion since it
checks that the current thread is holding the
mutex.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Allow userspace to register for more than just
action frames by giving the frame subtype, and
make it possible to use this in various modes
as well.
With some tweaks and some added functionality
this will, in the future, also be usable in AP
mode and be able to replace the cooked monitor
interface currently used in that case.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When sending action frames, we want to verify
that we do that on the correct channel. However,
checking the channel type in addition can get in
the way, since the channel type could change on
the fly during an association, and it's not
useful to have the channel type anyway since it
has no effect on the transmission. Therefore,
make it optional to specify so that if wanted,
it can still be checked, but is not required.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
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 <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Johannes Berg
Ben Greear
Jouni Malinen
Eric W. Biederman
Daniel Drake
Michal Kazior
Vasanthakumar Thiagarajan
Rajkumar Manoharan
Jouni Malinen
Sven Neumann
Luciano Coelho
Jouni Malinen
Javier Cardona
John W. Linville
Eric Dumazet
Johannes Berg