mac80211: report OBSS beacons

If there's an interface in AP mode, OBSS beacons
are needed by hostapd/wpa_s to implement logic to
enable/disable protection etc. Report the frames
and set the capability flag.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/ieee80211_i.h

@@ -184,12 +184,15 @@ enum ieee80211_packet_rx_flags {
  * enum ieee80211_rx_flags - RX data flags
  *
  * @IEEE80211_RX_CMNTR: received on cooked monitor already
+ * @IEEE80211_RX_BEACON_REPORTED: This frame was already reported
+ *	to cfg80211_report_obss_beacon().
  *
  * These flags are used across handling multiple interfaces
  * for a single frame.
  */
 enum ieee80211_rx_flags {
 	IEEE80211_RX_CMNTR		= BIT(0),
+	IEEE80211_RX_BEACON_REPORTED	= BIT(1),
 };
 
 struct ieee80211_rx_data {

net/mac80211/main.c

@@ -593,7 +593,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
 
 	wiphy->flags |= WIPHY_FLAG_NETNS_OK |
 			WIPHY_FLAG_4ADDR_AP |
-			WIPHY_FLAG_4ADDR_STATION;
+			WIPHY_FLAG_4ADDR_STATION |
+			WIPHY_FLAG_REPORTS_OBSS;
 
 	if (!ops->set_key)
 		wiphy->flags |= WIPHY_FLAG_IBSS_RSN;

net/mac80211/rx.c

@@ -2188,6 +2188,18 @@ ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
 	if (!ieee80211_is_mgmt(mgmt->frame_control))
 		return RX_DROP_MONITOR;
 
+	if (rx->sdata->vif.type == NL80211_IFTYPE_AP &&
+	    ieee80211_is_beacon(mgmt->frame_control) &&
+	    !(rx->flags & IEEE80211_RX_BEACON_REPORTED)) {
+		struct ieee80211_rx_status *status;
+
+		status = IEEE80211_SKB_RXCB(rx->skb);
+		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
+					    rx->skb->data, rx->skb->len,
+					    status->freq, GFP_ATOMIC);
+		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
+	}
+
 	if (!(status->rx_flags & IEEE80211_RX_RA_MATCH))
 		return RX_DROP_MONITOR;