Now that we have a pointer to the TX STA even when it's
not authenticated/... yet, fix the TX link selection in
hwsim to select only among the valid links for the STA,
requiring a STA pointer here. Also implement a simple
round-robin between links to make life more interesting.

While at it, also consider A3 when translating to link
addresses.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Use the link ID provided in TX frame metadata to select the correct
channel. For now, always select the link with the lowest link ID and
do some address translation.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Make mac80211_hwsim_sta_rc_update() iterate over all the STA links.

This is somewhat temporary, we really should add the link to the
API, but then hwsim still calls it internally and would need this.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In some cases, e.g. with Qualcomm devices and management
frames, or in hwsim, frames may be reported from the driver
with link addresses, but for decryption and matching needs
we really want to have them with MLD addresses. Support the
translation on RX.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When an MLO AP is transmitting to a non-MLO station, addr2 should be set
to a link address. This should be done before the frame is encrypted as
otherwise aad verification would fail. In case of software encryption
this can't be left for the device to handle, and should be done by
mac80211 when building the frame hdr.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When we create a station with a non-default link, then
we should have a link address, and we definitely need
to insert it into the link hash table on insertion.

Split the API into with and without link creation and
if it has a link, insert the link into the link hash
table on sta_info_insert().

Fixes: ba6ddab9 ("wifi: mac80211: maintain link-sta hash table")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In MLO, we need to transmit to another MLD and select
the link to it, which requires knowing the station.
But in TX, mac80211 will not give us a station that's
not added to the driver, which in the older add/remove
API is only done later.

Implement the new API in MLO so we know about the STA
at all times and get a pointer during TX as well.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In AP/mesh where the stations are added by userspace, we
limit the number of A-MSDU subframes according to the
extended capabilities.

Refactor the code and extend that also to client-side.

Fixes: 506bcfa8 ("mac80211: limit the A-MSDU Tx based on peer's capabilities")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Split out much of the code in ieee80211_set_associated()
into a new ieee80211_link_set_associated() which can be
called per link later for MLO.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add a helper function cfg80211_get_iftype_ext_capa() to
look up interface type-specific (extended) capabilities.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If NEED_DTIM_BEFORE_ASSOC isn't set, then we don't need
to enter an RCU critical section and look up the beacon
elements.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Factor out the code to set up the assoc link into a
new function ieee80211_setup_assoc_link().

While at it, also modify the 'override' handling to
just take into account whether or not the conn_flags
were changed, which is what we need to setup again
the channel later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There's no need to pass the address, we can look at the auth_data
inside the function rather than outside.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Refactor the per-link setup out of ieee80211_assoc_success()
into a new function ieee80211_assoc_config_link().

It looks useless for now to parse the elements again inside
ieee80211_assoc_config_link(), but that will be done with
the link ID in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Refactor ieee80211_prep_channel() to make the link argument
optional and add a conn_flags pointer argument instead, so
that we can later use this for links that don't exist yet
to build the right information for MLO.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For MLO, we will need to build these elements per link, so
factor out the code that does this, returning the capability,
to simplify building the multi-link element in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

With MLO, when we'll disconnect from an AP MLD, we'll just
destroy all the links. Therefore, the only thing we (may)
need to reset is the deflink data, so switch back to that
and adjust the comments accordingly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For MLO we'll need to read flags not directly from the link as
it may not even exist yet if we're just setting up flags for
a secondary link before sending the association request, so
pass the incoming conn_flags separately. Also, while at it,
pass the sdata/link separately as for non-tracking now the
link may be NULL.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We'll need ieee80211_prep_channel() in other code for MLO
later, so move the code up - unchanged for now - to avoid
forward declarations in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Refactor the code here since we need to have it also for each
link station after association in MLO later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The flag here is currently per interface, but the way we
set and clear it means it should be per link, so change
it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Change ieee80211_check_rate_mask() to use a link rather than
the sdata and deflink/bss_conf.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When sending an authentication frame from an MLD, include
the multi-link element with the MLD address and use the
link address for transmission.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Clean up the code building the supported channels element
a little bit by using a local variable instead of the long
line.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When a link is stopped for removal, release the channel
context it may have.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For now, prohibit DEAUTH_NEED_MGD_TX_PREP since we can't
really transmit this on a specific link yet as we don't
know which links are active.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The new NL80211_CMD_ADD_LINK_STA and NL80211_CMD_MODIFY_LINK_STA
commands have strict policy validation, so fix the policy so it
can be validated correctly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The underlying mac80211 code cannot deal with fragmented
elements for purposes of sorting the elements into the
association frame, so reject those inside the link. We
might want to reject them inside the assoc frame, but
they're used today for FILS, so cannot do that.

The non-inheritance element inside the links similarly
cannot be handled by mac80211, and outside the links it
makes no sense.

Reject both since using them could lead to an incorrect
implementation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When we associate, we'll include all the elements for the
link we're sending the association request on in the frame
and the specific ones for other links in the multi-link
element container. Prohibit adding link-specific elements
for the association link.

Fixes: d648c230 ("wifi: nl80211: support MLO in auth/assoc")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The link loop will always have a valid link so that
it's always set, but static checkers don't always
see that, so set it to NULL explicitly.

Fixes: efbabc11 ("cfg80211: Indicate MLO connection info in connect and roam callbacks")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since struct ieee80211_bss_conf already contains link_id,
passing link_id is not necessary.
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since mac80211 already has a protected pointer to link_conf,
pass it to the driver to avoid additional RCU locking.
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

At least while we don't have any more specific interface
combinations support, add a simple flag for MLO support,
we can keep this later based on something other than the
wiphy flag.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Recalculate min channel context for the given or all interface
links, depending on the caller. For a station state change, we
need to recalculate all of them since we don't know which link
(or multiple) it might be on.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

We check here that we don't enable TX (netif_carrier_ok())
before we actually start using some channel context, but to
our knowledge this check has never triggered, and with MLO
it's just wrong since links can be added and removed much
more dynamically than before.

Simply remove the checks, there's no really good way to do
anything that would replace them.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This simplifies hostapd implementation, since it didn't
switch to NL80211_CMD_SET_CHANNEL.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Allow link source address on TX.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Allow transmitting EAPOL frames not only from the interface
address (which is the MLD address) but also any link addresses,
in order to support non-MLO stations on AP interfaces.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In case of authentication with a legacy station, link addressed EAPOL
frames should be sent. Support it.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Set the MLD parameters in NL80211_CMD_SET_STATION handling
to be able to change an MLD station.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>