mac80211: handle operating mode notif in beacon/assoc response

In beacons and association response frames an AP may include an
operating mode notification element to advertise changes in the
number of spatial streams it can receive. Handle this using the
existing function that handles the action frame, but only handle
NSS changes, not bandwidth changes which aren't allowed here.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 23 insertions, 3 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index e6da6bf8cc27..f2c6f7794f35 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2217,6 +2217,21 @@ static bool ieee80211_assoc_success(struct ieee80211_sub_if_data *sdata,
                                                   elems.ht_operation,
                                                   cbss->bssid, false);
 
+        /*
+         * If an operating mode notification IE is present, override the
+         * NSS calculation (that would be done in rate_control_rate_init())
+         * and use the # of streams from that element.
+         */
+        if (elems.opmode_notif &&
+            !(*elems.opmode_notif & IEEE80211_OPMODE_NOTIF_RX_NSS_TYPE_BF)) {
+                u8 nss;
+
+                nss = *elems.opmode_notif & IEEE80211_OPMODE_NOTIF_RX_NSS_MASK;
+                nss >>= IEEE80211_OPMODE_NOTIF_RX_NSS_SHIFT;
+                nss += 1;
+                sta->sta.rx_nss = nss;
+        }
+
         rate_control_rate_init(sta);
 
         if (ifmgd->flags & IEEE80211_STA_MFP_ENABLED)
@@ -2489,6 +2504,7 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
         struct ieee80211_local *local = sdata->local;
         struct ieee80211_chanctx_conf *chanctx_conf;
         struct ieee80211_channel *chan;
+        struct sta_info *sta;
         u32 changed = 0;
         bool erp_valid;
         u8 erp_value = 0;
@@ -2728,14 +2744,18 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
                         le16_to_cpu(mgmt->u.beacon.capab_info),
                         erp_valid, erp_value);
 
-
         mutex_lock(&local->sta_mtx);
+        sta = sta_info_get(sdata, bssid);
+
         if (elems.ht_cap_elem && elems.ht_operation && elems.wmm_param &&
             !(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
-                changed |= ieee80211_config_ht_tx(sdata,
-                                                  sta_info_get(sdata, bssid),
+                changed |= ieee80211_config_ht_tx(sdata, sta,
                                                   elems.ht_operation,
                                                   bssid, true);
+
+        if (sta && elems.opmode_notif)
+                ieee80211_vht_handle_opmode(sdata, sta, *elems.opmode_notif,
+                                            rx_status->band, true);
         mutex_unlock(&local->sta_mtx);
 
         if (elems.country_elem && elems.pwr_constr_elem &&