scan.c revision fcc6cb0c13555e78c2d47257b6d1b5e59b0c419a
1/*
2 * cfg80211 scan result handling
3 *
4 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
5 */
6#include <linux/kernel.h>
7#include <linux/module.h>
8#include <linux/netdevice.h>
9#include <linux/wireless.h>
10#include <linux/nl80211.h>
11#include <linux/etherdevice.h>
12#include <net/arp.h>
13#include <net/cfg80211.h>
14#include <net/iw_handler.h>
15#include "core.h"
16#include "nl80211.h"
17#include "wext-compat.h"
18
19#define IEEE80211_SCAN_RESULT_EXPIRE	(15 * HZ)
20
21void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev, bool leak)
22{
23	struct cfg80211_scan_request *request;
24	struct net_device *dev;
25#ifdef CONFIG_WIRELESS_EXT
26	union iwreq_data wrqu;
27#endif
28
29	ASSERT_RDEV_LOCK(rdev);
30
31	request = rdev->scan_req;
32
33	if (!request)
34		return;
35
36	dev = request->dev;
37
38	/*
39	 * This must be before sending the other events!
40	 * Otherwise, wpa_supplicant gets completely confused with
41	 * wext events.
42	 */
43	cfg80211_sme_scan_done(dev);
44
45	if (request->aborted)
46		nl80211_send_scan_aborted(rdev, dev);
47	else
48		nl80211_send_scan_done(rdev, dev);
49
50#ifdef CONFIG_WIRELESS_EXT
51	if (!request->aborted) {
52		memset(&wrqu, 0, sizeof(wrqu));
53
54		wireless_send_event(dev, SIOCGIWSCAN, &wrqu, NULL);
55	}
56#endif
57
58	dev_put(dev);
59
60	rdev->scan_req = NULL;
61
62	/*
63	 * OK. If this is invoked with "leak" then we can't
64	 * free this ... but we've cleaned it up anyway. The
65	 * driver failed to call the scan_done callback, so
66	 * all bets are off, it might still be trying to use
67	 * the scan request or not ... if it accesses the dev
68	 * in there (it shouldn't anyway) then it may crash.
69	 */
70	if (!leak)
71		kfree(request);
72}
73
74void __cfg80211_scan_done(struct work_struct *wk)
75{
76	struct cfg80211_registered_device *rdev;
77
78	rdev = container_of(wk, struct cfg80211_registered_device,
79			    scan_done_wk);
80
81	cfg80211_lock_rdev(rdev);
82	___cfg80211_scan_done(rdev, false);
83	cfg80211_unlock_rdev(rdev);
84}
85
86void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
87{
88	WARN_ON(request != wiphy_to_dev(request->wiphy)->scan_req);
89
90	request->aborted = aborted;
91	schedule_work(&wiphy_to_dev(request->wiphy)->scan_done_wk);
92}
93EXPORT_SYMBOL(cfg80211_scan_done);
94
95static void bss_release(struct kref *ref)
96{
97	struct cfg80211_internal_bss *bss;
98
99	bss = container_of(ref, struct cfg80211_internal_bss, ref);
100	if (bss->pub.free_priv)
101		bss->pub.free_priv(&bss->pub);
102
103	if (bss->ies_allocated)
104		kfree(bss->pub.information_elements);
105
106	BUG_ON(atomic_read(&bss->hold));
107
108	kfree(bss);
109}
110
111/* must hold dev->bss_lock! */
112void cfg80211_bss_age(struct cfg80211_registered_device *dev,
113                      unsigned long age_secs)
114{
115	struct cfg80211_internal_bss *bss;
116	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);
117
118	list_for_each_entry(bss, &dev->bss_list, list) {
119		bss->ts -= age_jiffies;
120	}
121}
122
123/* must hold dev->bss_lock! */
124void cfg80211_bss_expire(struct cfg80211_registered_device *dev)
125{
126	struct cfg80211_internal_bss *bss, *tmp;
127	bool expired = false;
128
129	list_for_each_entry_safe(bss, tmp, &dev->bss_list, list) {
130		if (atomic_read(&bss->hold))
131			continue;
132		if (!time_after(jiffies, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE))
133			continue;
134		list_del(&bss->list);
135		rb_erase(&bss->rbn, &dev->bss_tree);
136		kref_put(&bss->ref, bss_release);
137		expired = true;
138	}
139
140	if (expired)
141		dev->bss_generation++;
142}
143
144static u8 *find_ie(u8 num, u8 *ies, int len)
145{
146	while (len > 2 && ies[0] != num) {
147		len -= ies[1] + 2;
148		ies += ies[1] + 2;
149	}
150	if (len < 2)
151		return NULL;
152	if (len < 2 + ies[1])
153		return NULL;
154	return ies;
155}
156
157static int cmp_ies(u8 num, u8 *ies1, size_t len1, u8 *ies2, size_t len2)
158{
159	const u8 *ie1 = find_ie(num, ies1, len1);
160	const u8 *ie2 = find_ie(num, ies2, len2);
161	int r;
162
163	if (!ie1 && !ie2)
164		return 0;
165	if (!ie1 || !ie2)
166		return -1;
167
168	r = memcmp(ie1 + 2, ie2 + 2, min(ie1[1], ie2[1]));
169	if (r == 0 && ie1[1] != ie2[1])
170		return ie2[1] - ie1[1];
171	return r;
172}
173
174static bool is_bss(struct cfg80211_bss *a,
175		   const u8 *bssid,
176		   const u8 *ssid, size_t ssid_len)
177{
178	const u8 *ssidie;
179
180	if (bssid && compare_ether_addr(a->bssid, bssid))
181		return false;
182
183	if (!ssid)
184		return true;
185
186	ssidie = find_ie(WLAN_EID_SSID,
187			 a->information_elements,
188			 a->len_information_elements);
189	if (!ssidie)
190		return false;
191	if (ssidie[1] != ssid_len)
192		return false;
193	return memcmp(ssidie + 2, ssid, ssid_len) == 0;
194}
195
196static bool is_mesh(struct cfg80211_bss *a,
197		    const u8 *meshid, size_t meshidlen,
198		    const u8 *meshcfg)
199{
200	const u8 *ie;
201
202	if (!is_zero_ether_addr(a->bssid))
203		return false;
204
205	ie = find_ie(WLAN_EID_MESH_ID,
206		     a->information_elements,
207		     a->len_information_elements);
208	if (!ie)
209		return false;
210	if (ie[1] != meshidlen)
211		return false;
212	if (memcmp(ie + 2, meshid, meshidlen))
213		return false;
214
215	ie = find_ie(WLAN_EID_MESH_CONFIG,
216		     a->information_elements,
217		     a->len_information_elements);
218	if (!ie)
219		return false;
220	if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
221		return false;
222
223	/*
224	 * Ignore mesh capability (last two bytes of the IE) when
225	 * comparing since that may differ between stations taking
226	 * part in the same mesh.
227	 */
228	return memcmp(ie + 2, meshcfg, IEEE80211_MESH_CONFIG_LEN - 2) == 0;
229}
230
231static int cmp_bss(struct cfg80211_bss *a,
232		   struct cfg80211_bss *b)
233{
234	int r;
235
236	if (a->channel != b->channel)
237		return b->channel->center_freq - a->channel->center_freq;
238
239	r = memcmp(a->bssid, b->bssid, ETH_ALEN);
240	if (r)
241		return r;
242
243	if (is_zero_ether_addr(a->bssid)) {
244		r = cmp_ies(WLAN_EID_MESH_ID,
245			    a->information_elements,
246			    a->len_information_elements,
247			    b->information_elements,
248			    b->len_information_elements);
249		if (r)
250			return r;
251		return cmp_ies(WLAN_EID_MESH_CONFIG,
252			       a->information_elements,
253			       a->len_information_elements,
254			       b->information_elements,
255			       b->len_information_elements);
256	}
257
258	return cmp_ies(WLAN_EID_SSID,
259		       a->information_elements,
260		       a->len_information_elements,
261		       b->information_elements,
262		       b->len_information_elements);
263}
264
265struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
266				      struct ieee80211_channel *channel,
267				      const u8 *bssid,
268				      const u8 *ssid, size_t ssid_len,
269				      u16 capa_mask, u16 capa_val)
270{
271	struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
272	struct cfg80211_internal_bss *bss, *res = NULL;
273
274	spin_lock_bh(&dev->bss_lock);
275
276	list_for_each_entry(bss, &dev->bss_list, list) {
277		if ((bss->pub.capability & capa_mask) != capa_val)
278			continue;
279		if (channel && bss->pub.channel != channel)
280			continue;
281		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
282			res = bss;
283			kref_get(&res->ref);
284			break;
285		}
286	}
287
288	spin_unlock_bh(&dev->bss_lock);
289	if (!res)
290		return NULL;
291	return &res->pub;
292}
293EXPORT_SYMBOL(cfg80211_get_bss);
294
295struct cfg80211_bss *cfg80211_get_mesh(struct wiphy *wiphy,
296				       struct ieee80211_channel *channel,
297				       const u8 *meshid, size_t meshidlen,
298				       const u8 *meshcfg)
299{
300	struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
301	struct cfg80211_internal_bss *bss, *res = NULL;
302
303	spin_lock_bh(&dev->bss_lock);
304
305	list_for_each_entry(bss, &dev->bss_list, list) {
306		if (channel && bss->pub.channel != channel)
307			continue;
308		if (is_mesh(&bss->pub, meshid, meshidlen, meshcfg)) {
309			res = bss;
310			kref_get(&res->ref);
311			break;
312		}
313	}
314
315	spin_unlock_bh(&dev->bss_lock);
316	if (!res)
317		return NULL;
318	return &res->pub;
319}
320EXPORT_SYMBOL(cfg80211_get_mesh);
321
322
323static void rb_insert_bss(struct cfg80211_registered_device *dev,
324			  struct cfg80211_internal_bss *bss)
325{
326	struct rb_node **p = &dev->bss_tree.rb_node;
327	struct rb_node *parent = NULL;
328	struct cfg80211_internal_bss *tbss;
329	int cmp;
330
331	while (*p) {
332		parent = *p;
333		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);
334
335		cmp = cmp_bss(&bss->pub, &tbss->pub);
336
337		if (WARN_ON(!cmp)) {
338			/* will sort of leak this BSS */
339			return;
340		}
341
342		if (cmp < 0)
343			p = &(*p)->rb_left;
344		else
345			p = &(*p)->rb_right;
346	}
347
348	rb_link_node(&bss->rbn, parent, p);
349	rb_insert_color(&bss->rbn, &dev->bss_tree);
350}
351
352static struct cfg80211_internal_bss *
353rb_find_bss(struct cfg80211_registered_device *dev,
354	    struct cfg80211_internal_bss *res)
355{
356	struct rb_node *n = dev->bss_tree.rb_node;
357	struct cfg80211_internal_bss *bss;
358	int r;
359
360	while (n) {
361		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
362		r = cmp_bss(&res->pub, &bss->pub);
363
364		if (r == 0)
365			return bss;
366		else if (r < 0)
367			n = n->rb_left;
368		else
369			n = n->rb_right;
370	}
371
372	return NULL;
373}
374
375static struct cfg80211_internal_bss *
376cfg80211_bss_update(struct cfg80211_registered_device *dev,
377		    struct cfg80211_internal_bss *res,
378		    bool overwrite)
379{
380	struct cfg80211_internal_bss *found = NULL;
381	const u8 *meshid, *meshcfg;
382
383	/*
384	 * The reference to "res" is donated to this function.
385	 */
386
387	if (WARN_ON(!res->pub.channel)) {
388		kref_put(&res->ref, bss_release);
389		return NULL;
390	}
391
392	res->ts = jiffies;
393
394	if (is_zero_ether_addr(res->pub.bssid)) {
395		/* must be mesh, verify */
396		meshid = find_ie(WLAN_EID_MESH_ID, res->pub.information_elements,
397				 res->pub.len_information_elements);
398		meshcfg = find_ie(WLAN_EID_MESH_CONFIG,
399				  res->pub.information_elements,
400				  res->pub.len_information_elements);
401		if (!meshid || !meshcfg ||
402		    meshcfg[1] != IEEE80211_MESH_CONFIG_LEN) {
403			/* bogus mesh */
404			kref_put(&res->ref, bss_release);
405			return NULL;
406		}
407	}
408
409	spin_lock_bh(&dev->bss_lock);
410
411	found = rb_find_bss(dev, res);
412
413	if (found) {
414		found->pub.beacon_interval = res->pub.beacon_interval;
415		found->pub.tsf = res->pub.tsf;
416		found->pub.signal = res->pub.signal;
417		found->pub.capability = res->pub.capability;
418		found->ts = res->ts;
419
420		/* overwrite IEs */
421		if (overwrite) {
422			size_t used = dev->wiphy.bss_priv_size + sizeof(*res);
423			size_t ielen = res->pub.len_information_elements;
424
425			if (!found->ies_allocated && ksize(found) >= used + ielen) {
426				memcpy(found->pub.information_elements,
427				       res->pub.information_elements, ielen);
428				found->pub.len_information_elements = ielen;
429			} else {
430				u8 *ies = found->pub.information_elements;
431
432				if (found->ies_allocated)
433					ies = krealloc(ies, ielen, GFP_ATOMIC);
434				else
435					ies = kmalloc(ielen, GFP_ATOMIC);
436
437				if (ies) {
438					memcpy(ies, res->pub.information_elements, ielen);
439					found->ies_allocated = true;
440					found->pub.information_elements = ies;
441					found->pub.len_information_elements = ielen;
442				}
443			}
444		}
445
446		kref_put(&res->ref, bss_release);
447	} else {
448		/* this "consumes" the reference */
449		list_add_tail(&res->list, &dev->bss_list);
450		rb_insert_bss(dev, res);
451		found = res;
452	}
453
454	dev->bss_generation++;
455	spin_unlock_bh(&dev->bss_lock);
456
457	kref_get(&found->ref);
458	return found;
459}
460
461struct cfg80211_bss*
462cfg80211_inform_bss(struct wiphy *wiphy,
463		    struct ieee80211_channel *channel,
464		    const u8 *bssid,
465		    u64 timestamp, u16 capability, u16 beacon_interval,
466		    const u8 *ie, size_t ielen,
467		    s32 signal, gfp_t gfp)
468{
469	struct cfg80211_internal_bss *res;
470	size_t privsz;
471
472	if (WARN_ON(!wiphy))
473		return NULL;
474
475	privsz = wiphy->bss_priv_size;
476
477	if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
478			(signal < 0 || signal > 100)))
479		return NULL;
480
481	res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
482	if (!res)
483		return NULL;
484
485	memcpy(res->pub.bssid, bssid, ETH_ALEN);
486	res->pub.channel = channel;
487	res->pub.signal = signal;
488	res->pub.tsf = timestamp;
489	res->pub.beacon_interval = beacon_interval;
490	res->pub.capability = capability;
491	/* point to after the private area */
492	res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
493	memcpy(res->pub.information_elements, ie, ielen);
494	res->pub.len_information_elements = ielen;
495
496	kref_init(&res->ref);
497
498	res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, 0);
499	if (!res)
500		return NULL;
501
502	if (res->pub.capability & WLAN_CAPABILITY_ESS)
503		regulatory_hint_found_beacon(wiphy, channel, gfp);
504
505	/* cfg80211_bss_update gives us a referenced result */
506	return &res->pub;
507}
508EXPORT_SYMBOL(cfg80211_inform_bss);
509
510struct cfg80211_bss *
511cfg80211_inform_bss_frame(struct wiphy *wiphy,
512			  struct ieee80211_channel *channel,
513			  struct ieee80211_mgmt *mgmt, size_t len,
514			  s32 signal, gfp_t gfp)
515{
516	struct cfg80211_internal_bss *res;
517	size_t ielen = len - offsetof(struct ieee80211_mgmt,
518				      u.probe_resp.variable);
519	bool overwrite;
520	size_t privsz = wiphy->bss_priv_size;
521
522	if (WARN_ON(wiphy->signal_type == NL80211_BSS_SIGNAL_UNSPEC &&
523	            (signal < 0 || signal > 100)))
524		return NULL;
525
526	if (WARN_ON(!mgmt || !wiphy ||
527		    len < offsetof(struct ieee80211_mgmt, u.probe_resp.variable)))
528		return NULL;
529
530	res = kzalloc(sizeof(*res) + privsz + ielen, gfp);
531	if (!res)
532		return NULL;
533
534	memcpy(res->pub.bssid, mgmt->bssid, ETH_ALEN);
535	res->pub.channel = channel;
536	res->pub.signal = signal;
537	res->pub.tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
538	res->pub.beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
539	res->pub.capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
540	/* point to after the private area */
541	res->pub.information_elements = (u8 *)res + sizeof(*res) + privsz;
542	memcpy(res->pub.information_elements, mgmt->u.probe_resp.variable, ielen);
543	res->pub.len_information_elements = ielen;
544
545	kref_init(&res->ref);
546
547	overwrite = ieee80211_is_probe_resp(mgmt->frame_control);
548
549	res = cfg80211_bss_update(wiphy_to_dev(wiphy), res, overwrite);
550	if (!res)
551		return NULL;
552
553	if (res->pub.capability & WLAN_CAPABILITY_ESS)
554		regulatory_hint_found_beacon(wiphy, channel, gfp);
555
556	/* cfg80211_bss_update gives us a referenced result */
557	return &res->pub;
558}
559EXPORT_SYMBOL(cfg80211_inform_bss_frame);
560
561void cfg80211_put_bss(struct cfg80211_bss *pub)
562{
563	struct cfg80211_internal_bss *bss;
564
565	if (!pub)
566		return;
567
568	bss = container_of(pub, struct cfg80211_internal_bss, pub);
569	kref_put(&bss->ref, bss_release);
570}
571EXPORT_SYMBOL(cfg80211_put_bss);
572
573void cfg80211_unlink_bss(struct wiphy *wiphy, struct cfg80211_bss *pub)
574{
575	struct cfg80211_registered_device *dev = wiphy_to_dev(wiphy);
576	struct cfg80211_internal_bss *bss;
577
578	if (WARN_ON(!pub))
579		return;
580
581	bss = container_of(pub, struct cfg80211_internal_bss, pub);
582
583	spin_lock_bh(&dev->bss_lock);
584
585	list_del(&bss->list);
586	dev->bss_generation++;
587	rb_erase(&bss->rbn, &dev->bss_tree);
588
589	spin_unlock_bh(&dev->bss_lock);
590
591	kref_put(&bss->ref, bss_release);
592}
593EXPORT_SYMBOL(cfg80211_unlink_bss);
594
595#ifdef CONFIG_WIRELESS_EXT
596int cfg80211_wext_siwscan(struct net_device *dev,
597			  struct iw_request_info *info,
598			  union iwreq_data *wrqu, char *extra)
599{
600	struct cfg80211_registered_device *rdev;
601	struct wiphy *wiphy;
602	struct iw_scan_req *wreq = NULL;
603	struct cfg80211_scan_request *creq;
604	int i, err, n_channels = 0;
605	enum ieee80211_band band;
606
607	if (!netif_running(dev))
608		return -ENETDOWN;
609
610	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
611
612	if (IS_ERR(rdev))
613		return PTR_ERR(rdev);
614
615	if (rdev->scan_req) {
616		err = -EBUSY;
617		goto out;
618	}
619
620	wiphy = &rdev->wiphy;
621
622	for (band = 0; band < IEEE80211_NUM_BANDS; band++)
623		if (wiphy->bands[band])
624			n_channels += wiphy->bands[band]->n_channels;
625
626	creq = kzalloc(sizeof(*creq) + sizeof(struct cfg80211_ssid) +
627		       n_channels * sizeof(void *),
628		       GFP_ATOMIC);
629	if (!creq) {
630		err = -ENOMEM;
631		goto out;
632	}
633
634	creq->wiphy = wiphy;
635	creq->dev = dev;
636	/* SSIDs come after channels */
637	creq->ssids = (void *)&creq->channels[n_channels];
638	creq->n_channels = n_channels;
639	creq->n_ssids = 1;
640
641	/* all channels */
642	i = 0;
643	for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
644		int j;
645		if (!wiphy->bands[band])
646			continue;
647		for (j = 0; j < wiphy->bands[band]->n_channels; j++) {
648			creq->channels[i] = &wiphy->bands[band]->channels[j];
649			i++;
650		}
651	}
652
653	/* translate scan request */
654	if (wrqu->data.length == sizeof(struct iw_scan_req)) {
655		wreq = (struct iw_scan_req *)extra;
656
657		if (wrqu->data.flags & IW_SCAN_THIS_ESSID) {
658			if (wreq->essid_len > IEEE80211_MAX_SSID_LEN)
659				return -EINVAL;
660			memcpy(creq->ssids[0].ssid, wreq->essid, wreq->essid_len);
661			creq->ssids[0].ssid_len = wreq->essid_len;
662		}
663		if (wreq->scan_type == IW_SCAN_TYPE_PASSIVE)
664			creq->n_ssids = 0;
665	}
666
667	rdev->scan_req = creq;
668	err = rdev->ops->scan(wiphy, dev, creq);
669	if (err) {
670		rdev->scan_req = NULL;
671		kfree(creq);
672	} else {
673		nl80211_send_scan_start(rdev, dev);
674		dev_hold(dev);
675	}
676 out:
677	cfg80211_unlock_rdev(rdev);
678	return err;
679}
680EXPORT_SYMBOL_GPL(cfg80211_wext_siwscan);
681
682static void ieee80211_scan_add_ies(struct iw_request_info *info,
683				   struct cfg80211_bss *bss,
684				   char **current_ev, char *end_buf)
685{
686	u8 *pos, *end, *next;
687	struct iw_event iwe;
688
689	if (!bss->information_elements ||
690	    !bss->len_information_elements)
691		return;
692
693	/*
694	 * If needed, fragment the IEs buffer (at IE boundaries) into short
695	 * enough fragments to fit into IW_GENERIC_IE_MAX octet messages.
696	 */
697	pos = bss->information_elements;
698	end = pos + bss->len_information_elements;
699
700	while (end - pos > IW_GENERIC_IE_MAX) {
701		next = pos + 2 + pos[1];
702		while (next + 2 + next[1] - pos < IW_GENERIC_IE_MAX)
703			next = next + 2 + next[1];
704
705		memset(&iwe, 0, sizeof(iwe));
706		iwe.cmd = IWEVGENIE;
707		iwe.u.data.length = next - pos;
708		*current_ev = iwe_stream_add_point(info, *current_ev,
709						   end_buf, &iwe, pos);
710
711		pos = next;
712	}
713
714	if (end > pos) {
715		memset(&iwe, 0, sizeof(iwe));
716		iwe.cmd = IWEVGENIE;
717		iwe.u.data.length = end - pos;
718		*current_ev = iwe_stream_add_point(info, *current_ev,
719						   end_buf, &iwe, pos);
720	}
721}
722
723static inline unsigned int elapsed_jiffies_msecs(unsigned long start)
724{
725	unsigned long end = jiffies;
726
727	if (end >= start)
728		return jiffies_to_msecs(end - start);
729
730	return jiffies_to_msecs(end + (MAX_JIFFY_OFFSET - start) + 1);
731}
732
733static char *
734ieee80211_bss(struct wiphy *wiphy, struct iw_request_info *info,
735	      struct cfg80211_internal_bss *bss, char *current_ev,
736	      char *end_buf)
737{
738	struct iw_event iwe;
739	u8 *buf, *cfg, *p;
740	u8 *ie = bss->pub.information_elements;
741	int rem = bss->pub.len_information_elements, i, sig;
742	bool ismesh = false;
743
744	memset(&iwe, 0, sizeof(iwe));
745	iwe.cmd = SIOCGIWAP;
746	iwe.u.ap_addr.sa_family = ARPHRD_ETHER;
747	memcpy(iwe.u.ap_addr.sa_data, bss->pub.bssid, ETH_ALEN);
748	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
749					  IW_EV_ADDR_LEN);
750
751	memset(&iwe, 0, sizeof(iwe));
752	iwe.cmd = SIOCGIWFREQ;
753	iwe.u.freq.m = ieee80211_frequency_to_channel(bss->pub.channel->center_freq);
754	iwe.u.freq.e = 0;
755	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
756					  IW_EV_FREQ_LEN);
757
758	memset(&iwe, 0, sizeof(iwe));
759	iwe.cmd = SIOCGIWFREQ;
760	iwe.u.freq.m = bss->pub.channel->center_freq;
761	iwe.u.freq.e = 6;
762	current_ev = iwe_stream_add_event(info, current_ev, end_buf, &iwe,
763					  IW_EV_FREQ_LEN);
764
765	if (wiphy->signal_type != CFG80211_SIGNAL_TYPE_NONE) {
766		memset(&iwe, 0, sizeof(iwe));
767		iwe.cmd = IWEVQUAL;
768		iwe.u.qual.updated = IW_QUAL_LEVEL_UPDATED |
769				     IW_QUAL_NOISE_INVALID |
770				     IW_QUAL_QUAL_UPDATED;
771		switch (wiphy->signal_type) {
772		case CFG80211_SIGNAL_TYPE_MBM:
773			sig = bss->pub.signal / 100;
774			iwe.u.qual.level = sig;
775			iwe.u.qual.updated |= IW_QUAL_DBM;
776			if (sig < -110)		/* rather bad */
777				sig = -110;
778			else if (sig > -40)	/* perfect */
779				sig = -40;
780			/* will give a range of 0 .. 70 */
781			iwe.u.qual.qual = sig + 110;
782			break;
783		case CFG80211_SIGNAL_TYPE_UNSPEC:
784			iwe.u.qual.level = bss->pub.signal;
785			/* will give range 0 .. 100 */
786			iwe.u.qual.qual = bss->pub.signal;
787			break;
788		default:
789			/* not reached */
790			break;
791		}
792		current_ev = iwe_stream_add_event(info, current_ev, end_buf,
793						  &iwe, IW_EV_QUAL_LEN);
794	}
795
796	memset(&iwe, 0, sizeof(iwe));
797	iwe.cmd = SIOCGIWENCODE;
798	if (bss->pub.capability & WLAN_CAPABILITY_PRIVACY)
799		iwe.u.data.flags = IW_ENCODE_ENABLED | IW_ENCODE_NOKEY;
800	else
801		iwe.u.data.flags = IW_ENCODE_DISABLED;
802	iwe.u.data.length = 0;
803	current_ev = iwe_stream_add_point(info, current_ev, end_buf,
804					  &iwe, "");
805
806	while (rem >= 2) {
807		/* invalid data */
808		if (ie[1] > rem - 2)
809			break;
810
811		switch (ie[0]) {
812		case WLAN_EID_SSID:
813			memset(&iwe, 0, sizeof(iwe));
814			iwe.cmd = SIOCGIWESSID;
815			iwe.u.data.length = ie[1];
816			iwe.u.data.flags = 1;
817			current_ev = iwe_stream_add_point(info, current_ev, end_buf,
818							  &iwe, ie + 2);
819			break;
820		case WLAN_EID_MESH_ID:
821			memset(&iwe, 0, sizeof(iwe));
822			iwe.cmd = SIOCGIWESSID;
823			iwe.u.data.length = ie[1];
824			iwe.u.data.flags = 1;
825			current_ev = iwe_stream_add_point(info, current_ev, end_buf,
826							  &iwe, ie + 2);
827			break;
828		case WLAN_EID_MESH_CONFIG:
829			ismesh = true;
830			if (ie[1] != IEEE80211_MESH_CONFIG_LEN)
831				break;
832			buf = kmalloc(50, GFP_ATOMIC);
833			if (!buf)
834				break;
835			cfg = ie + 2;
836			memset(&iwe, 0, sizeof(iwe));
837			iwe.cmd = IWEVCUSTOM;
838			sprintf(buf, "Mesh network (version %d)", cfg[0]);
839			iwe.u.data.length = strlen(buf);
840			current_ev = iwe_stream_add_point(info, current_ev,
841							  end_buf,
842							  &iwe, buf);
843			sprintf(buf, "Path Selection Protocol ID: "
844				"0x%02X%02X%02X%02X", cfg[1], cfg[2], cfg[3],
845							cfg[4]);
846			iwe.u.data.length = strlen(buf);
847			current_ev = iwe_stream_add_point(info, current_ev,
848							  end_buf,
849							  &iwe, buf);
850			sprintf(buf, "Path Selection Metric ID: "
851				"0x%02X%02X%02X%02X", cfg[5], cfg[6], cfg[7],
852							cfg[8]);
853			iwe.u.data.length = strlen(buf);
854			current_ev = iwe_stream_add_point(info, current_ev,
855							  end_buf,
856							  &iwe, buf);
857			sprintf(buf, "Congestion Control Mode ID: "
858				"0x%02X%02X%02X%02X", cfg[9], cfg[10],
859							cfg[11], cfg[12]);
860			iwe.u.data.length = strlen(buf);
861			current_ev = iwe_stream_add_point(info, current_ev,
862							  end_buf,
863							  &iwe, buf);
864			sprintf(buf, "Channel Precedence: "
865				"0x%02X%02X%02X%02X", cfg[13], cfg[14],
866							cfg[15], cfg[16]);
867			iwe.u.data.length = strlen(buf);
868			current_ev = iwe_stream_add_point(info, current_ev,
869							  end_buf,
870							  &iwe, buf);
871			kfree(buf);
872			break;
873		case WLAN_EID_SUPP_RATES:
874		case WLAN_EID_EXT_SUPP_RATES:
875			/* display all supported rates in readable format */
876			p = current_ev + iwe_stream_lcp_len(info);
877
878			memset(&iwe, 0, sizeof(iwe));
879			iwe.cmd = SIOCGIWRATE;
880			/* Those two flags are ignored... */
881			iwe.u.bitrate.fixed = iwe.u.bitrate.disabled = 0;
882
883			for (i = 0; i < ie[1]; i++) {
884				iwe.u.bitrate.value =
885					((ie[i + 2] & 0x7f) * 500000);
886				p = iwe_stream_add_value(info, current_ev, p,
887						end_buf, &iwe, IW_EV_PARAM_LEN);
888			}
889			current_ev = p;
890			break;
891		}
892		rem -= ie[1] + 2;
893		ie += ie[1] + 2;
894	}
895
896	if (bss->pub.capability & (WLAN_CAPABILITY_ESS | WLAN_CAPABILITY_IBSS)
897	    || ismesh) {
898		memset(&iwe, 0, sizeof(iwe));
899		iwe.cmd = SIOCGIWMODE;
900		if (ismesh)
901			iwe.u.mode = IW_MODE_MESH;
902		else if (bss->pub.capability & WLAN_CAPABILITY_ESS)
903			iwe.u.mode = IW_MODE_MASTER;
904		else
905			iwe.u.mode = IW_MODE_ADHOC;
906		current_ev = iwe_stream_add_event(info, current_ev, end_buf,
907						  &iwe, IW_EV_UINT_LEN);
908	}
909
910	buf = kmalloc(30, GFP_ATOMIC);
911	if (buf) {
912		memset(&iwe, 0, sizeof(iwe));
913		iwe.cmd = IWEVCUSTOM;
914		sprintf(buf, "tsf=%016llx", (unsigned long long)(bss->pub.tsf));
915		iwe.u.data.length = strlen(buf);
916		current_ev = iwe_stream_add_point(info, current_ev, end_buf,
917						  &iwe, buf);
918		memset(&iwe, 0, sizeof(iwe));
919		iwe.cmd = IWEVCUSTOM;
920		sprintf(buf, " Last beacon: %ums ago",
921			elapsed_jiffies_msecs(bss->ts));
922		iwe.u.data.length = strlen(buf);
923		current_ev = iwe_stream_add_point(info, current_ev,
924						  end_buf, &iwe, buf);
925		kfree(buf);
926	}
927
928	ieee80211_scan_add_ies(info, &bss->pub, &current_ev, end_buf);
929
930	return current_ev;
931}
932
933
934static int ieee80211_scan_results(struct cfg80211_registered_device *dev,
935				  struct iw_request_info *info,
936				  char *buf, size_t len)
937{
938	char *current_ev = buf;
939	char *end_buf = buf + len;
940	struct cfg80211_internal_bss *bss;
941
942	spin_lock_bh(&dev->bss_lock);
943	cfg80211_bss_expire(dev);
944
945	list_for_each_entry(bss, &dev->bss_list, list) {
946		if (buf + len - current_ev <= IW_EV_ADDR_LEN) {
947			spin_unlock_bh(&dev->bss_lock);
948			return -E2BIG;
949		}
950		current_ev = ieee80211_bss(&dev->wiphy, info, bss,
951					   current_ev, end_buf);
952	}
953	spin_unlock_bh(&dev->bss_lock);
954	return current_ev - buf;
955}
956
957
958int cfg80211_wext_giwscan(struct net_device *dev,
959			  struct iw_request_info *info,
960			  struct iw_point *data, char *extra)
961{
962	struct cfg80211_registered_device *rdev;
963	int res;
964
965	if (!netif_running(dev))
966		return -ENETDOWN;
967
968	rdev = cfg80211_get_dev_from_ifindex(dev_net(dev), dev->ifindex);
969
970	if (IS_ERR(rdev))
971		return PTR_ERR(rdev);
972
973	if (rdev->scan_req) {
974		res = -EAGAIN;
975		goto out;
976	}
977
978	res = ieee80211_scan_results(rdev, info, extra, data->length);
979	data->length = 0;
980	if (res >= 0) {
981		data->length = res;
982		res = 0;
983	}
984
985 out:
986	cfg80211_unlock_rdev(rdev);
987	return res;
988}
989EXPORT_SYMBOL_GPL(cfg80211_wext_giwscan);
990#endif
991