mac80211: count authorized stations per BSS

Currently, each AP interface will send multicast
traffic if any interface has a station entry even
if that station entry is allocated only. With the
new station state management we can easily fix it
by adding a counter that counts each authorized
station only and send multicast traffic only when
the correct interface has at least one authorized
station.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

4 files changed, 20 insertions, 16 deletions

diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index 8df28910b8ee..176c08ffb13c 100644
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -321,6 +321,7 @@ static ssize_t ieee80211_if_parse_tkip_mic_test(
 __IEEE80211_IF_FILE_W(tkip_mic_test);
 
 /* AP attributes */
+IEEE80211_IF_FILE(num_sta_authorized, u.ap.num_sta_authorized, ATOMIC);
 IEEE80211_IF_FILE(num_sta_ps, u.ap.num_sta_ps, ATOMIC);
 IEEE80211_IF_FILE(dtim_count, u.ap.dtim_count, DEC);
 
@@ -458,6 +459,7 @@ static void add_ap_files(struct ieee80211_sub_if_data *sdata)
         DEBUGFS_ADD(rc_rateidx_mask_2ghz);
         DEBUGFS_ADD(rc_rateidx_mask_5ghz);
 
+        DEBUGFS_ADD(num_sta_authorized);
         DEBUGFS_ADD(num_sta_ps);
         DEBUGFS_ADD(dtim_count);
         DEBUGFS_ADD(num_buffered_multicast);
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 96fe75410bbe..9516c3088fba 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -243,6 +243,7 @@ struct ieee80211_if_ap {
         u8 tim[sizeof(unsigned long) * BITS_TO_LONGS(IEEE80211_MAX_AID + 1)];
         struct sk_buff_head ps_bc_buf;
         atomic_t num_sta_ps; /* number of stations in PS mode */
+        atomic_t num_sta_authorized; /* number of authorized stations */
         int dtim_count;
         bool dtim_bc_mc;
 };
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index b22775cdcdf5..141315ce17d8 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1567,17 +1567,21 @@ int sta_info_move_state_checked(struct sta_info *sta,
                         return -EINVAL;
                 break;
         case IEEE80211_STA_ASSOC:
-                if (sta->sta_state == IEEE80211_STA_AUTH)
+                if (sta->sta_state == IEEE80211_STA_AUTH) {
                         set_bit(WLAN_STA_ASSOC, &sta->_flags);
-                else if (sta->sta_state == IEEE80211_STA_AUTHORIZED)
+                } else if (sta->sta_state == IEEE80211_STA_AUTHORIZED) {
+                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP)
+                                atomic_dec(&sta->sdata->u.ap.num_sta_authorized);
                         clear_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
-                else
+                } else
                         return -EINVAL;
                 break;
         case IEEE80211_STA_AUTHORIZED:
-                if (sta->sta_state == IEEE80211_STA_ASSOC)
+                if (sta->sta_state == IEEE80211_STA_ASSOC) {
+                        if (sta->sdata->vif.type == NL80211_IFTYPE_AP)
+                                atomic_inc(&sta->sdata->u.ap.num_sta_authorized);
                         set_bit(WLAN_STA_AUTHORIZED, &sta->_flags);
-                else
+                } else
                         return -EINVAL;
                 break;
         default:
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 50c4be9a6404..6bbd6cccb4a0 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -304,17 +304,14 @@ ieee80211_tx_h_check_assoc(struct ieee80211_tx_data *tx)
                         I802_DEBUG_INC(tx->local->tx_handlers_drop_not_assoc);
                         return TX_DROP;
                 }
-        } else {
-                if (unlikely(ieee80211_is_data(hdr->frame_control) &&
-                             tx->local->num_sta == 0 &&
-                             tx->sdata->vif.type != NL80211_IFTYPE_ADHOC)) {
-                        /*
-                         * No associated STAs - no need to send multicast
-                         * frames.
-                         */
-                        return TX_DROP;
-                }
-                return TX_CONTINUE;
+        } else if (unlikely(tx->sdata->vif.type == NL80211_IFTYPE_AP &&
+                            ieee80211_is_data(hdr->frame_control) &&
+                            !atomic_read(&tx->sdata->u.ap.num_sta_authorized))) {
+                /*
+                 * No associated STAs - no need to send multicast
+                 * frames.
+                 */
+                return TX_DROP;
         }
 
         return TX_CONTINUE;