mac80211: remove VLAIS usage from mac80211

Replaced the use of a Variable Length Array In Struct (VLAIS) with a
C99 compliant equivalent. This is the original VLAIS struct.

struct {
	struct aead_request     req;
	u8                      priv[crypto_aead_reqsize(tfm)];
} aead_req;

This patch instead allocates the appropriate amount of memory using a
char array.

The new code can be compiled with both gcc and clang.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
[small style cleanups]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: allow userspace to take ownership of interfaces

When dynamically creating interfaces from userspace, e.g. for P2P usage,
such interfaces are usually owned by the process that created them, i.e.
wpa_supplicant. Should wpa_supplicant crash, such interfaces will often
cease operating properly and cause problems on restarting the process.

To avoid this problem, introduce an ownership concept for interfaces. If
an interface is owned by a netlink socket, then it will be destroyed if
the netlink socket is closed for any reason, including if the process it
belongs to crashed. This gives us a race-free way to get rid of any such
interfaces.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: add vif to flush call

This will allow the low level driver to make decision based
on the vif such as queues etc...
Since the vif might be NULL, we can't add it to the tracing
functions.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
[fix staging rtl8821ae driver]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: regulatory: use RCU_INIT_POINTER

rcu_assign_pointer() ensures that the initialization of a structure is
carried out before storing a pointer to that structure. However, in the
case that NULL is assigned there's no structure to initialize so using
RCU_INIT_POINTER instead is safe and more efficient.

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
[rewrite commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: use RCU_INIT_POINTER

rcu_assign_pointer() ensures that the initialization of a structure is
carried out before storing a pointer to that structure. However, in the
case that NULL is assigned there's no structure to initialize so using
RCU_INIT_POINTER instead is safe and more efficient.

Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
[squash eight tiny patches, rewrite commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: slightly clean up of cfg80211_sme_connect()

Wdev->ssid_len has already been set in cfg80211_connect() and is equal
to connect->ssid_len. Use wdev->ssid_len instead of connect->ssid_len
so it will be consistent with previous ssid assignment statement.

If bss is found in cfg80211_get_conn_bss(), wdev->conn->state is set
to CFG80211_CONN_AUTHENTICATE_NEXT in there. So it's not needed to set
it manually to CFG80211_CONN_AUTHENTICATE_NEXT if bss is found in that
function.

Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: Add indoor only and GO concurrent channel attributes

The FCC are clarifying some soft configuration requirements,
which among other include the following:

1. Indoor operation, where a device can use channels requiring indoor
   operation, subject to that it can guarantee indoor operation,
   i.e., the device is connected to AC Power or the device is under
   the control of a local master that is acting as an AP and is
   connected to AC Power.
2. Concurrent GO operation, where devices may instantiate a P2P GO
   while they are under the guidance of an authorized master. For example,
   on a channel on which a BSS is connected to an authorized master, i.e.,
   with DFS and radar detection capability in the UNII band.

See https://apps.fcc.gov/eas/comments/GetPublishedDocument.html?id=327&tn=528122

Add support for advertising Indoor-only and GO-Concurrent channel
properties.

Signed-off-by: David Spinadel <david.spinadel@intel.com>
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: Add Kconfig option for cellular BS hints

Move the regulatory cellular base station hints support under
a specific configuration option and make the option depend
on CFG80211_CERTIFICATION_ONUS.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: Enable GO operation on additional channels

Allow GO operation on a channel marked with IEEE80211_CHAN_GO_CONCURRENT
iff there is an active station interface that is associated to
an AP operating on the same channel in the 2 GHz band or the same UNII band
(in the 5 GHz band). This relaxation is not allowed if the channel is
marked with IEEE80211_CHAN_RADAR.

Note that this is a permissive approach to the FCC definitions,
that require a clear assessment that the device operating the AP is
an authorized master, i.e., with radar detection and DFS capabilities.

It is assumed that such restrictions are enforced by user space.
Furthermore, it is assumed, that if the conditions that allowed for
the operation of the GO on such a channel change, i.e., the station
interface disconnected from the AP, it is the responsibility of user
space to evacuate the GO from the channel.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: Add an option to hint indoor operation

Add the option to hint the wireless core that it is operating in an indoor
environment.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: Enable GO operation on indoor channels

Allow GO operation on a channel marked with IEEE80211_CHAN_INDOOR_ONLY
iff there is a user hint indicating that the platform is operating in
an indoor environment, i.e., the platform is a printer or media center
device.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211: refactor cfg80211_can_use_iftype_chan()

Separate the code that counts the interface types and channels from
the code that check the interface combinations.  The new function that
checks for combinations is exported so it can be called by the
drivers.

This is done in preparation for moving the interface combinations
checks out of cfg80211.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211/mac80211: refactor cfg80211_chandef_dfs_required()

Some interface types don't require DFS (such as STATION, P2P_CLIENT
etc).  In order to centralize these decisions, make
cfg80211_chandef_dfs_required() take the iftype into consideration.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211/mac80211: move interface counting for combination check to mac80211

Move the counting part of the interface combination check from
cfg80211 to mac80211.

This is needed to simplify locking when the driver has to perform a
combination check by itself (eg. with channel-switch).

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211/mac80211: move combination check to mac80211 for ibss

Now that mac80211 can check the interface combinations itself, move
the combinations check from cfg80211 to mac80211 when joining an IBSS.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
cfg80211/mac80211: move more combination checks to mac80211

Get rid of the cfg80211_can_add_interface() and
cfg80211_can_change_interface() functions by moving that functionality
to mac80211.  With this patch all interface combination checks are now
out of cfg80211 (except for the channel switch case which will be
addressed in a future commit).

Additionally, modify the ieee80211_check_combinations() function so
that an undefined chandef can be passed, in order to use it before a
channel is defined.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: protect AP VLAN list with local->mtx

It was impossible to change chanctx of master AP
for AP VLANs because the copy function requires
RTNL which can't be simply taken in mac80211 code
due to possible deadlocks.

This is required for future chanctx reservation
that re-bind vifs to new chanctx. This requires
safe AP VLAN iteration without RTNL.

Now VLANs can be iterated while holding either
RTNL or local->mtx because the list is modified
while holding both of these locks.

Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: split ieee80211_vif_change_channel in two

ieee80211_vif_change_channel() locks chanctx_mtx.  When implementing
channel reservation for CS, we will need to call the function to
change channel when the lock is already held, so split the part that
requires the lock out and leave the locking in the original function.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: refactor ieee80211_assign/unassign_vif_chanctx into one

Combine the functions into one, so that we can switch from one context
to the other without having to unassign and assign separately.  This
is needed by the channel reservation functionality because otherwise
we have a small period of time when the chanctx is set to NULL, which
can cause problems if someone else is trying to dereference it.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
mac80211: implement chanctx reservation

In order to support channel switch with multiple vifs and multiple
contexts, we implement a concept of channel context reservation.  This
allows us to reserve a channel context to be used later.

The reservation functionality is not tied directly to channel switch
and may be used in other situations (eg. reserving a channel context
during IBSS join).

We first check if an existing compatible context exists and if it
does, we reserve it.  If there is no compatible context we create a
new one and reserve it.

Additionally, split ieee80211_vif_copy_chanctx_to_vlans() so we can
call it while already holding the chanctx mutex.

Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>