1 files changed, 937 insertions, 0 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
new file mode 100644
index 0000000..8e6685e
--- /dev/null
+++ b/net/mac80211/scan.c
@@ -0,0 +1,937 @@
+/*
+ * Scanning implementation
+ *
+ * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
+ * Copyright 2004, Instant802 Networks, Inc.
+ * Copyright 2005, Devicescape Software, Inc.
+ * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* TODO:
+ * order BSS list by RSSI(?) ("quality of AP")
+ * scan result table filtering (by capability (privacy, IBSS/BSS, WPA/RSN IE,
+ *    SSID)
+ */
+
+#include <linux/wireless.h>
+#include <linux/if_arp.h>
+#include <net/mac80211.h>
+#include <net/iw_handler.h>
+
+#include "ieee80211_i.h"
+#include "mesh.h"
+
+#define IEEE80211_PROBE_DELAY (HZ / 33)
+#define IEEE80211_CHANNEL_TIME (HZ / 33)
+#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 5)
+
+void ieee80211_rx_bss_list_init(struct ieee80211_local *local)
+{
+	spin_lock_init(&local->bss_lock);
+	INIT_LIST_HEAD(&local->bss_list);
+}
+
+void ieee80211_rx_bss_list_deinit(struct ieee80211_local *local)
+{
+	struct ieee80211_bss *bss, *tmp;
+
+	list_for_each_entry_safe(bss, tmp, &local->bss_list, list)
+		ieee80211_rx_bss_put(local, bss);
+}
+
+struct ieee80211_bss *
+ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq,
+		     u8 *ssid, u8 ssid_len)
+{
+	struct ieee80211_bss *bss;
+
+	spin_lock_bh(&local->bss_lock);
+	bss = local->bss_hash[STA_HASH(bssid)];
+	while (bss) {
+		if (!bss_mesh_cfg(bss) &&
+		    !memcmp(bss->bssid, bssid, ETH_ALEN) &&
+		    bss->freq == freq &&
+		    bss->ssid_len == ssid_len &&
+		    (ssid_len == 0 || !memcmp(bss->ssid, ssid, ssid_len))) {
+			atomic_inc(&bss->users);
+			break;
+		}
+		bss = bss->hnext;
+	}
+	spin_unlock_bh(&local->bss_lock);
+	return bss;
+}
+
+/* Caller must hold local->bss_lock */
+static void __ieee80211_rx_bss_hash_add(struct ieee80211_local *local,
+					struct ieee80211_bss *bss)
+{
+	u8 hash_idx;
+
+	if (bss_mesh_cfg(bss))
+		hash_idx = mesh_id_hash(bss_mesh_id(bss),
+					bss_mesh_id_len(bss));
+	else
+		hash_idx = STA_HASH(bss->bssid);
+
+	bss->hnext = local->bss_hash[hash_idx];
+	local->bss_hash[hash_idx] = bss;
+}
+
+/* Caller must hold local->bss_lock */
+static void __ieee80211_rx_bss_hash_del(struct ieee80211_local *local,
+					struct ieee80211_bss *bss)
+{
+	struct ieee80211_bss *b, *prev = NULL;
+	b = local->bss_hash[STA_HASH(bss->bssid)];
+	while (b) {
+		if (b == bss) {
+			if (!prev)
+				local->bss_hash[STA_HASH(bss->bssid)] =
+					bss->hnext;
+			else
+				prev->hnext = bss->hnext;
+			break;
+		}
+		prev = b;
+		b = b->hnext;
+	}
+}
+
+struct ieee80211_bss *
+ieee80211_rx_bss_add(struct ieee80211_local *local, u8 *bssid, int freq,
+		     u8 *ssid, u8 ssid_len)
+{
+	struct ieee80211_bss *bss;
+
+	bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
+	if (!bss)
+		return NULL;
+	atomic_set(&bss->users, 2);
+	memcpy(bss->bssid, bssid, ETH_ALEN);
+	bss->freq = freq;
+	if (ssid && ssid_len <= IEEE80211_MAX_SSID_LEN) {
+		memcpy(bss->ssid, ssid, ssid_len);
+		bss->ssid_len = ssid_len;
+	}
+
+	spin_lock_bh(&local->bss_lock);
+	/* TODO: order by RSSI? */
+	list_add_tail(&bss->list, &local->bss_list);
+	__ieee80211_rx_bss_hash_add(local, bss);
+	spin_unlock_bh(&local->bss_lock);
+	return bss;
+}
+
+#ifdef CONFIG_MAC80211_MESH
+static struct ieee80211_bss *
+ieee80211_rx_mesh_bss_get(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
+			  u8 *mesh_cfg, int freq)
+{
+	struct ieee80211_bss *bss;
+
+	spin_lock_bh(&local->bss_lock);
+	bss = local->bss_hash[mesh_id_hash(mesh_id, mesh_id_len)];
+	while (bss) {
+		if (bss_mesh_cfg(bss) &&
+		    !memcmp(bss_mesh_cfg(bss), mesh_cfg, MESH_CFG_CMP_LEN) &&
+		    bss->freq == freq &&
+		    mesh_id_len == bss->mesh_id_len &&
+		    (mesh_id_len == 0 || !memcmp(bss->mesh_id, mesh_id,
+						 mesh_id_len))) {
+			atomic_inc(&bss->users);
+			break;
+		}
+		bss = bss->hnext;
+	}
+	spin_unlock_bh(&local->bss_lock);
+	return bss;
+}
+
+static struct ieee80211_bss *
+ieee80211_rx_mesh_bss_add(struct ieee80211_local *local, u8 *mesh_id, int mesh_id_len,
+			  u8 *mesh_cfg, int mesh_config_len, int freq)
+{
+	struct ieee80211_bss *bss;
+
+	if (mesh_config_len != MESH_CFG_LEN)
+		return NULL;
+
+	bss = kzalloc(sizeof(*bss), GFP_ATOMIC);
+	if (!bss)
+		return NULL;
+
+	bss->mesh_cfg = kmalloc(MESH_CFG_CMP_LEN, GFP_ATOMIC);
+	if (!bss->mesh_cfg) {
+		kfree(bss);
+		return NULL;
+	}
+
+	if (mesh_id_len && mesh_id_len <= IEEE80211_MAX_MESH_ID_LEN) {
+		bss->mesh_id = kmalloc(mesh_id_len, GFP_ATOMIC);
+		if (!bss->mesh_id) {
+			kfree(bss->mesh_cfg);
+			kfree(bss);
+			return NULL;
+		}
+		memcpy(bss->mesh_id, mesh_id, mesh_id_len);
+	}
+
+	atomic_set(&bss->users, 2);
+	memcpy(bss->mesh_cfg, mesh_cfg, MESH_CFG_CMP_LEN);
+	bss->mesh_id_len = mesh_id_len;
+	bss->freq = freq;
+	spin_lock_bh(&local->bss_lock);
+	/* TODO: order by RSSI? */
+	list_add_tail(&bss->list, &local->bss_list);
+	__ieee80211_rx_bss_hash_add(local, bss);
+	spin_unlock_bh(&local->bss_lock);
+	return bss;
+}
+#endif
+
+static void ieee80211_rx_bss_free(struct ieee80211_bss *bss)
+{
+	kfree(bss->ies);
+	kfree(bss_mesh_id(bss));
+	kfree(bss_mesh_cfg(bss));
+	kfree(bss);
+}
+
+void ieee80211_rx_bss_put(struct ieee80211_local *local,
+			  struct ieee80211_bss *bss)
+{
+	local_bh_disable();
+	if (!atomic_dec_and_lock(&bss->users, &local->bss_lock)) {
+		local_bh_enable();
+		return;
+	}
+
+	__ieee80211_rx_bss_hash_del(local, bss);
+	list_del(&bss->list);
+	spin_unlock_bh(&local->bss_lock);
+	ieee80211_rx_bss_free(bss);
+}
+
+struct ieee80211_bss *
+ieee80211_bss_info_update(struct ieee80211_local *local,
+			  struct ieee80211_rx_status *rx_status,
+			  struct ieee80211_mgmt *mgmt,
+			  size_t len,
+			  struct ieee802_11_elems *elems,
+			  int freq, bool beacon)
+{
+	struct ieee80211_bss *bss;
+	int clen;
+
+#ifdef CONFIG_MAC80211_MESH
+	if (elems->mesh_config)
+		bss = ieee80211_rx_mesh_bss_get(local, elems->mesh_id,
+				elems->mesh_id_len, elems->mesh_config, freq);
+	else
+#endif
+		bss = ieee80211_rx_bss_get(local, mgmt->bssid, freq,
+					   elems->ssid, elems->ssid_len);
+	if (!bss) {
+#ifdef CONFIG_MAC80211_MESH
+		if (elems->mesh_config)
+			bss = ieee80211_rx_mesh_bss_add(local, elems->mesh_id,
+				elems->mesh_id_len, elems->mesh_config,
+				elems->mesh_config_len, freq);
+		else
+#endif
+			bss = ieee80211_rx_bss_add(local, mgmt->bssid, freq,
+						  elems->ssid, elems->ssid_len);
+		if (!bss)
+			return NULL;
+	} else {
+#if 0
+		/* TODO: order by RSSI? */
+		spin_lock_bh(&local->bss_lock);
+		list_move_tail(&bss->list, &local->bss_list);
+		spin_unlock_bh(&local->bss_lock);
+#endif
+	}
+
+	/* save the ERP value so that it is available at association time */
+	if (elems->erp_info && elems->erp_info_len >= 1) {
+		bss->erp_value = elems->erp_info[0];
+		bss->has_erp_value = 1;
+	}
+
+	bss->beacon_int = le16_to_cpu(mgmt->u.beacon.beacon_int);
+	bss->capability = le16_to_cpu(mgmt->u.beacon.capab_info);
+
+	if (elems->tim) {
+		struct ieee80211_tim_ie *tim_ie =
+			(struct ieee80211_tim_ie *)elems->tim;
+		bss->dtim_period = tim_ie->dtim_period;
+	}
+
+	/* set default value for buggy APs */
+	if (!elems->tim || bss->dtim_period == 0)
+		bss->dtim_period = 1;
+
+	bss->supp_rates_len = 0;
+	if (elems->supp_rates) {
+		clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
+		if (clen > elems->supp_rates_len)
+			clen = elems->supp_rates_len;
+		memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates,
+		       clen);
+		bss->supp_rates_len += clen;
+	}
+	if (elems->ext_supp_rates) {
+		clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len;
+		if (clen > elems->ext_supp_rates_len)
+			clen = elems->ext_supp_rates_len;
+		memcpy(&bss->supp_rates[bss->supp_rates_len],
+		       elems->ext_supp_rates, clen);
+		bss->supp_rates_len += clen;
+	}
+
+	bss->band = rx_status->band;
+
+	bss->timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
+	bss->last_update = jiffies;
+	bss->signal = rx_status->signal;
+	bss->noise = rx_status->noise;
+	bss->qual = rx_status->qual;
+	bss->wmm_used = elems->wmm_param || elems->wmm_info;
+
+	if (!beacon)
+		bss->last_probe_resp = jiffies;
+
+	/*
+	 * For probe responses, or if we don't have any information yet,
+	 * use the IEs from the beacon.
+	 */
+	if (!bss->ies || !beacon) {
+		if (bss->ies == NULL || bss->ies_len < elems->total_len) {
+			kfree(bss->ies);
+			bss->ies = kmalloc(elems->total_len, GFP_ATOMIC);
+		}
+		if (bss->ies) {
+			memcpy(bss->ies, elems->ie_start, elems->total_len);
+			bss->ies_len = elems->total_len;
+		} else
+			bss->ies_len = 0;
+	}
+
+	return bss;
+}
+
+ieee80211_rx_result
+ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
+		  struct ieee80211_rx_status *rx_status)
+{
+	struct ieee80211_mgmt *mgmt;
+	struct ieee80211_bss *bss;
+	u8 *elements;
+	struct ieee80211_channel *channel;
+	size_t baselen;
+	int freq;
+	__le16 fc;
+	bool presp, beacon = false;
+	struct ieee802_11_elems elems;
+
+	if (skb->len < 2)
+		return RX_DROP_UNUSABLE;
+
+	mgmt = (struct ieee80211_mgmt *) skb->data;
+	fc = mgmt->frame_control;
+
+	if (ieee80211_is_ctl(fc))
+		return RX_CONTINUE;
+
+	if (skb->len < 24)
+		return RX_DROP_MONITOR;
+
+	presp = ieee80211_is_probe_resp(fc);
+	if (presp) {
+		/* ignore ProbeResp to foreign address */
+		if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
+			return RX_DROP_MONITOR;
+
+		presp = true;
+		elements = mgmt->u.probe_resp.variable;
+		baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
+	} else {
+		beacon = ieee80211_is_beacon(fc);
+		baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
+		elements = mgmt->u.beacon.variable;
+	}
+
+	if (!presp && !beacon)
+		return RX_CONTINUE;
+
+	if (baselen > skb->len)
+		return RX_DROP_MONITOR;
+
+	ieee802_11_parse_elems(elements, skb->len - baselen, &elems);
+
+	if (elems.ds_params && elems.ds_params_len == 1)
+		freq = ieee80211_channel_to_frequency(elems.ds_params[0]);
+	else
+		freq = rx_status->freq;
+
+	channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq);
+
+	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
+		return RX_DROP_MONITOR;
+
+	bss = ieee80211_bss_info_update(sdata->local, rx_status,
+					mgmt, skb->len, &elems,
+					freq, beacon);
+	ieee80211_rx_bss_put(sdata->local, bss);
+
+	dev_kfree_skb(skb);
+	return RX_QUEUED;
+}
+
+static void ieee80211_send_nullfunc(struct ieee80211_local *local,
+				    struct ieee80211_sub_if_data *sdata,
+				    int powersave)
+{
+	struct sk_buff *skb;
+	struct ieee80211_hdr *nullfunc;
+	__le16 fc;
+
+	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 24);
+	if (!skb) {
+		printk(KERN_DEBUG "%s: failed to allocate buffer for nullfunc "
+		       "frame\n", sdata->dev->name);
+		return;
+	}
+	skb_reserve(skb, local->hw.extra_tx_headroom);
+
+	nullfunc = (struct ieee80211_hdr *) skb_put(skb, 24);
+	memset(nullfunc, 0, 24);
+	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
+			 IEEE80211_FCTL_TODS);
+	if (powersave)
+		fc |= cpu_to_le16(IEEE80211_FCTL_PM);
+	nullfunc->frame_control = fc;
+	memcpy(nullfunc->addr1, sdata->u.sta.bssid, ETH_ALEN);
+	memcpy(nullfunc->addr2, sdata->dev->dev_addr, ETH_ALEN);
+	memcpy(nullfunc->addr3, sdata->u.sta.bssid, ETH_ALEN);
+
+	ieee80211_tx_skb(sdata, skb, 0);
+}
+
+void ieee80211_scan_completed(struct ieee80211_hw *hw)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct ieee80211_sub_if_data *sdata;
+	union iwreq_data wrqu;
+
+	if (WARN_ON(!local->hw_scanning && !local->sw_scanning))
+		return;
+
+	local->last_scan_completed = jiffies;
+	memset(&wrqu, 0, sizeof(wrqu));
+
+	/*
+	 * local->scan_sdata could have been NULLed by the interface
+	 * down code in case we were scanning on an interface that is
+	 * being taken down.
+	 */
+	sdata = local->scan_sdata;
+	if (sdata)
+		wireless_send_event(sdata->dev, SIOCGIWSCAN, &wrqu, NULL);
+
+	if (local->hw_scanning) {
+		local->hw_scanning = false;
+		if (ieee80211_hw_config(local))
+			printk(KERN_DEBUG "%s: failed to restore operational "
+			       "channel after scan\n", wiphy_name(local->hw.wiphy));
+
+		goto done;
+	}
+
+	local->sw_scanning = false;
+	if (ieee80211_hw_config(local))
+		printk(KERN_DEBUG "%s: failed to restore operational "
+		       "channel after scan\n", wiphy_name(local->hw.wiphy));
+
+
+	netif_tx_lock_bh(local->mdev);
+	netif_addr_lock(local->mdev);
+	local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC;
+	local->ops->configure_filter(local_to_hw(local),
+				     FIF_BCN_PRBRESP_PROMISC,
+				     &local->filter_flags,
+				     local->mdev->mc_count,
+				     local->mdev->mc_list);
+
+	netif_addr_unlock(local->mdev);
+	netif_tx_unlock_bh(local->mdev);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		/* Tell AP we're back */
+		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
+			if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
+				ieee80211_send_nullfunc(local, sdata, 0);
+				netif_tx_wake_all_queues(sdata->dev);
+			}
+		} else
+			netif_tx_wake_all_queues(sdata->dev);
+	}
+	rcu_read_unlock();
+
+ done:
+	ieee80211_mlme_notify_scan_completed(local);
+	ieee80211_mesh_notify_scan_completed(local);
+}
+EXPORT_SYMBOL(ieee80211_scan_completed);
+
+
+void ieee80211_scan_work(struct work_struct *work)
+{
+	struct ieee80211_local *local =
+		container_of(work, struct ieee80211_local, scan_work.work);
+	struct ieee80211_sub_if_data *sdata = local->scan_sdata;
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_channel *chan;
+	int skip;
+	unsigned long next_delay = 0;
+
+	/*
+	 * Avoid re-scheduling when the sdata is going away.
+	 */
+	if (!netif_running(sdata->dev))
+		return;
+
+	switch (local->scan_state) {
+	case SCAN_SET_CHANNEL:
+		/*
+		 * Get current scan band. scan_band may be IEEE80211_NUM_BANDS
+		 * after we successfully scanned the last channel of the last
+		 * band (and the last band is supported by the hw)
+		 */
+		if (local->scan_band < IEEE80211_NUM_BANDS)
+			sband = local->hw.wiphy->bands[local->scan_band];
+		else
+			sband = NULL;
+
+		/*
+		 * If we are at an unsupported band and have more bands
+		 * left to scan, advance to the next supported one.
+		 */
+		while (!sband && local->scan_band < IEEE80211_NUM_BANDS - 1) {
+			local->scan_band++;
+			sband = local->hw.wiphy->bands[local->scan_band];
+			local->scan_channel_idx = 0;
+		}
+
+		/* if no more bands/channels left, complete scan */
+		if (!sband || local->scan_channel_idx >= sband->n_channels) {
+			ieee80211_scan_completed(local_to_hw(local));
+			return;
+		}
+		skip = 0;
+		chan = &sband->channels[local->scan_channel_idx];
+
+		if (chan->flags & IEEE80211_CHAN_DISABLED ||
+		    (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
+		     chan->flags & IEEE80211_CHAN_NO_IBSS))
+			skip = 1;
+
+		if (!skip) {
+			local->scan_channel = chan;
+			if (ieee80211_hw_config(local)) {
+				printk(KERN_DEBUG "%s: failed to set freq to "
+				       "%d MHz for scan\n", wiphy_name(local->hw.wiphy),
+				       chan->center_freq);
+				skip = 1;
+			}
+		}
+
+		/* advance state machine to next channel/band */
+		local->scan_channel_idx++;
+		if (local->scan_channel_idx >= sband->n_channels) {
+			/*
+			 * scan_band may end up == IEEE80211_NUM_BANDS, but
+			 * we'll catch that case above and complete the scan
+			 * if that is the case.
+			 */
+			local->scan_band++;
+			local->scan_channel_idx = 0;
+		}
+
+		if (skip)
+			break;
+
+		next_delay = IEEE80211_PROBE_DELAY +
+			     usecs_to_jiffies(local->hw.channel_change_time);
+		local->scan_state = SCAN_SEND_PROBE;
+		break;
+	case SCAN_SEND_PROBE:
+		next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+		local->scan_state = SCAN_SET_CHANNEL;
+
+		if (local->scan_channel->flags & IEEE80211_CHAN_PASSIVE_SCAN)
+			break;
+		ieee80211_send_probe_req(sdata, NULL, local->scan_ssid,
+					 local->scan_ssid_len);
+		next_delay = IEEE80211_CHANNEL_TIME;
+		break;
+	}
+
+	queue_delayed_work(local->hw.workqueue, &local->scan_work,
+			   next_delay);
+}
+
+
+int ieee80211_start_scan(struct ieee80211_sub_if_data *scan_sdata,
+			 u8 *ssid, size_t ssid_len)
+{
+	struct ieee80211_local *local = scan_sdata->local;
+	struct ieee80211_sub_if_data *sdata;
+
+	if (ssid_len > IEEE80211_MAX_SSID_LEN)
+		return -EINVAL;
+
+	/* MLME-SCAN.request (page 118)  page 144 (11.1.3.1)
+	 * BSSType: INFRASTRUCTURE, INDEPENDENT, ANY_BSS
+	 * BSSID: MACAddress
+	 * SSID
+	 * ScanType: ACTIVE, PASSIVE
+	 * ProbeDelay: delay (in microseconds) to be used prior to transmitting
+	 *    a Probe frame during active scanning
+	 * ChannelList
+	 * MinChannelTime (>= ProbeDelay), in TU
+	 * MaxChannelTime: (>= MinChannelTime), in TU
+	 */
+
+	 /* MLME-SCAN.confirm
+	  * BSSDescriptionSet
+	  * ResultCode: SUCCESS, INVALID_PARAMETERS
+	 */
+
+	if (local->sw_scanning || local->hw_scanning) {
+		if (local->scan_sdata == scan_sdata)
+			return 0;
+		return -EBUSY;
+	}
+
+	if (local->ops->hw_scan) {
+		int rc;
+
+		local->hw_scanning = true;
+		rc = local->ops->hw_scan(local_to_hw(local), ssid, ssid_len);
+		if (rc) {
+			local->hw_scanning = false;
+			return rc;
+		}
+		local->scan_sdata = scan_sdata;
+		return 0;
+	}
+
+	local->sw_scanning = true;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
+			if (sdata->u.sta.flags & IEEE80211_STA_ASSOCIATED) {
+				netif_tx_stop_all_queues(sdata->dev);
+				ieee80211_send_nullfunc(local, sdata, 1);
+			}
+		} else
+			netif_tx_stop_all_queues(sdata->dev);
+	}
+	rcu_read_unlock();
+
+	if (ssid) {
+		local->scan_ssid_len = ssid_len;
+		memcpy(local->scan_ssid, ssid, ssid_len);
+	} else
+		local->scan_ssid_len = 0;
+	local->scan_state = SCAN_SET_CHANNEL;
+	local->scan_channel_idx = 0;
+	local->scan_band = IEEE80211_BAND_2GHZ;
+	local->scan_sdata = scan_sdata;
+
+	netif_addr_lock_bh(local->mdev);
+	local->filter_flags |= FIF_BCN_PRBRESP_PROMISC;
+	local->ops->configure_filter(local_to_hw(local),
+				     FIF_BCN_PRBRESP_PROMISC,
+				     &local->filter_flags,
+				     local->mdev->mc_count,
+				     local->mdev->mc_list);
+	netif_addr_unlock_bh(local->mdev);
+
+	/* TODO: start scan as soon as all nullfunc frames are ACKed */
+	queue_delayed_work(local->hw.workqueue, &local->scan_work,
+			   IEEE80211_CHANNEL_TIME);
+
+	return 0;
+}
+
+
+int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
+			   u8 *ssid, size_t ssid_len)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_sta *ifsta;
+
+	if (sdata->vif.type != NL80211_IFTYPE_STATION)
+		return ieee80211_start_scan(sdata, ssid, ssid_len);
+
+	/*
+	 * STA has a state machine that might need to defer scanning
+	 * while it's trying to associate/authenticate, therefore we
+	 * queue it up to the state machine in that case.
+	 */
+
+	if (local->sw_scanning || local->hw_scanning) {
+		if (local->scan_sdata == sdata)
+			return 0;
+		return -EBUSY;
+	}
+
+	ifsta = &sdata->u.sta;
+
+	ifsta->scan_ssid_len = ssid_len;
+	if (ssid_len)
+		memcpy(ifsta->scan_ssid, ssid, ssid_len);
+	set_bit(IEEE80211_STA_REQ_SCAN, &ifsta->request);
+	queue_work(local->hw.workqueue, &ifsta->work);
+
+	return 0;
+}
+
+
+static void ieee80211_scan_add_ies(struct iw_request_info *info,
+				   struct ieee80211_bss *bss,
+				   char **current_ev, char *end_buf)
+{
+	u8 *pos, *end, *next;
+	struct iw_event iwe;
+
+	if (bss == NULL || bss->ies == NULL)
+		return;
+
+	/*
+	 * If needed, fragment the IEs buffer (at IE boundaries) into short
+	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
+	 */
+	pos = bss->ies;
+	end = pos + bss->ies_len;
+
+	while (end - pos > IW_GENERIC_IE_MAX) {
+		next = pos + 2 + pos[1];
+		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
+			next = next + 2 + next[1];
+
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = IWEVGENIE;
+		iwe.u.data.length = next - pos;
+		*current_ev = iwe_stream_add_point(info, *current_ev,
+						   end_buf, &iwe, pos);
+
+		pos = next;
+	}
+
+	if (end > pos) {
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = IWEVGENIE;
+		iwe.u.data.length = end - pos;
+		*current_ev = iwe_stream_add_point(info, *current_ev,
+						   end_buf, &iwe, pos);
+	}
+}
+
+
+static char *
+ieee80211_scan_result(struct ieee80211_local *local,
+		      struct iw_request_info *info,
+		      struct ieee80211_bss *bss,
+		      char *current_ev, char *end_buf)
+{
+	struct iw_event iwe;
+	char *buf;
+
+	if (time_after(jiffies,
+		       bss->last_update + IEEE80211_SCAN_RESULT_EXPIRE))
+		return current_ev;
+
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = SIOCGIWAP;
+	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
+	memcpy(iwe.u.ap_addr.sa_data, bss->bssid, ETH_ALEN);
+	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+					  IW_EV_ADDR_LEN);
+
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = SIOCGIWESSID;
+	if (bss_mesh_cfg(bss)) {
+		iwe.u.data.length = bss_mesh_id_len(bss);
+		iwe.u.data.flags = 1;
+		current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+						  &iwe, bss_mesh_id(bss));
+	} else {
+		iwe.u.data.length = bss->ssid_len;
+		iwe.u.data.flags = 1;
+		current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+						  &iwe, bss->ssid);
+	}
+
+	if (bss->capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
+	    || bss_mesh_cfg(bss)) {
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = SIOCGIWMODE;
+		if (bss_mesh_cfg(bss))
+			iwe.u.mode = IW_MODE_MESH;
+		else if (bss->capability & WLAN_CAPABILITY_ESS)
+			iwe.u.mode = IW_MODE_MASTER;
+		else
+			iwe.u.mode = IW_MODE_ADHOC;
+		current_ev = iwe_stream_add_event(info, current_ev, end_buf,
+						  &iwe, IW_EV_UINT_LEN);
+	}
+
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = SIOCGIWFREQ;
+	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->freq);
+	iwe.u.freq.e = 0;
+	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+					  IW_EV_FREQ_LEN);
+
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = SIOCGIWFREQ;
+	iwe.u.freq.m = bss->freq;
+	iwe.u.freq.e = 6;
+	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+					  IW_EV_FREQ_LEN);
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = IWEVQUAL;
+	iwe.u.qual.qual = bss->qual;
+	iwe.u.qual.level = bss->signal;
+	iwe.u.qual.noise = bss->noise;
+	iwe.u.qual.updated = local->wstats_flags;
+	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
+					  IW_EV_QUAL_LEN);
+
+	memset(&iwe, 0, sizeof(iwe));
+	iwe.cmd = SIOCGIWENCODE;
+	if (bss->capability & WLAN_CAPABILITY_PRIVACY)
+		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
+	else
+		iwe.u.data.flags = IW_ENCODE_DISABLED;
+	iwe.u.data.length = 0;
+	current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+					  &iwe, "");
+
+	ieee80211_scan_add_ies(info, bss, &current_ev, end_buf);
+
+	if (bss->supp_rates_len > 0) {
+		/* display all supported rates in readable format */
+		char *p = current_ev + iwe_stream_lcp_len(info);
+		int i;
+
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = SIOCGIWRATE;
+		/* Those two flags are ignored... */
+		iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
+
+		for (i = 0; i < bss->supp_rates_len; i++) {
+			iwe.u.bitrate.value = ((bss->supp_rates[i] &
+							0x7f) * 500000);
+			p = iwe_stream_add_value(info, current_ev, p,
+					end_buf, &iwe, IW_EV_PARAM_LEN);
+		}
+		current_ev = p;
+	}
+
+	buf = kmalloc(30, GFP_ATOMIC);
+	if (buf) {
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = IWEVCUSTOM;
+		sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->timestamp));
+		iwe.u.data.length = strlen(buf);
+		current_ev = iwe_stream_add_point(info, current_ev, end_buf,
+						  &iwe, buf);
+		memset(&iwe, 0, sizeof(iwe));
+		iwe.cmd = IWEVCUSTOM;
+		sprintf(buf, " Last beacon: %dms ago",
+			jiffies_to_msecs(jiffies - bss->last_update));
+		iwe.u.data.length = strlen(buf);
+		current_ev = iwe_stream_add_point(info, current_ev,
+						  end_buf, &iwe, buf);
+		kfree(buf);
+	}
+
+	if (bss_mesh_cfg(bss)) {
+		u8 *cfg = bss_mesh_cfg(bss);
+		buf = kmalloc(50, GFP_ATOMIC);
+		if (buf) {
+			memset(&iwe, 0, sizeof(iwe));
+			iwe.cmd = IWEVCUSTOM;
+			sprintf(buf, "Mesh network (version %d)", cfg[0]);
+			iwe.u.data.length = strlen(buf);
+			current_ev = iwe_stream_add_point(info, current_ev,
+							  end_buf,
+							  &iwe, buf);
+			sprintf(buf, "Path Selection Protocol ID: "
+				"0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
+							cfg[4]);
+			iwe.u.data.length = strlen(buf);
+			current_ev = iwe_stream_add_point(info, current_ev,
+							  end_buf,
+							  &iwe, buf);
+			sprintf(buf, "Path Selection Metric ID: "
+				"0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
+							cfg[8]);
+			iwe.u.data.length = strlen(buf);
+			current_ev = iwe_stream_add_point(info, current_ev,
+							  end_buf,
+							  &iwe, buf);
+			sprintf(buf, "Congestion Control Mode ID: "
+				"0x%02X%02X%02X%02X", cfg[9], cfg[10],
+							cfg[11], cfg[12]);
+			iwe.u.data.length = strlen(buf);
+			current_ev = iwe_stream_add_point(info, current_ev,
+							  end_buf,
+							  &iwe, buf);
+			sprintf(buf, "Channel Precedence: "
+				"0x%02X%02X%02X%02X", cfg[13], cfg[14],
+							cfg[15], cfg[16]);
+			iwe.u.data.length = strlen(buf);
+			current_ev = iwe_stream_add_point(info, current_ev,
+							  end_buf,
+							  &iwe, buf);
+			kfree(buf);
+		}
+	}
+
+	return current_ev;
+}
+
+
+int ieee80211_scan_results(struct ieee80211_local *local,
+			   struct iw_request_info *info,
+			   char *buf, size_t len)
+{
+	char *current_ev = buf;
+	char *end_buf = buf + len;
+	struct ieee80211_bss *bss;
+
+	spin_lock_bh(&local->bss_lock);
+	list_for_each_entry(bss, &local->bss_list, list) {
+		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
+			spin_unlock_bh(&local->bss_lock);
+			return -E2BIG;
+		}
+		current_ev = ieee80211_scan_result(local, info, bss,
+						       current_ev, end_buf);
+	}
+	spin_unlock_bh(&local->bss_lock);
+	return current_ev - buf;
+}