ieee80211_rx_h_mgmt_check(struct ieee80211_rx_data *rx)
{
	struct ieee80211_mgmt *mgmt = (struct ieee80211_mgmt *) rx->skb->data;
	struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);

	/*
	 * From here on, look only at management frames.
	 * Data and control frames are already handled,
	 * and unknown (reserved) frames are useless.
	 */
	if (rx->skb->len < 24)
		return RX_DROP_MONITOR;

	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)) {
		int sig = 0;

		if (ieee80211_hw_check(&rx->local->hw, SIGNAL_DBM) &&
		    !(status->flag & RX_FLAG_NO_SIGNAL_VAL))
			sig = status->signal;

		cfg80211_report_obss_beacon(rx->local->hw.wiphy,
					    rx->skb->data, rx->skb->len,
					    status->freq, sig);
		rx->flags |= IEEE80211_RX_BEACON_REPORTED;
	}

	if (ieee80211_drop_unencrypted_mgmt(rx))
		return RX_DROP_UNUSABLE;

	return RX_CONTINUE;
}
Unknown