xref: /linux/net/wireless/ibss.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Some IBSS support code for cfg80211.
3  *
4  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
5  */
6 
7 #include <linux/etherdevice.h>
8 #include <linux/if_arp.h>
9 #include <linux/slab.h>
10 #include <linux/export.h>
11 #include <net/cfg80211.h>
12 #include "wext-compat.h"
13 #include "nl80211.h"
14 #include "rdev-ops.h"
15 
16 
17 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid)
18 {
19 	struct wireless_dev *wdev = dev->ieee80211_ptr;
20 	struct cfg80211_bss *bss;
21 #ifdef CONFIG_CFG80211_WEXT
22 	union iwreq_data wrqu;
23 #endif
24 
25 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
26 		return;
27 
28 	if (!wdev->ssid_len)
29 		return;
30 
31 	bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid,
32 			       wdev->ssid, wdev->ssid_len,
33 			       WLAN_CAPABILITY_IBSS, WLAN_CAPABILITY_IBSS);
34 
35 	if (WARN_ON(!bss))
36 		return;
37 
38 	if (wdev->current_bss) {
39 		cfg80211_unhold_bss(wdev->current_bss);
40 		cfg80211_put_bss(&wdev->current_bss->pub);
41 	}
42 
43 	cfg80211_hold_bss(bss_from_pub(bss));
44 	wdev->current_bss = bss_from_pub(bss);
45 
46 	wdev->sme_state = CFG80211_SME_CONNECTED;
47 	cfg80211_upload_connect_keys(wdev);
48 
49 	nl80211_send_ibss_bssid(wiphy_to_dev(wdev->wiphy), dev, bssid,
50 				GFP_KERNEL);
51 #ifdef CONFIG_CFG80211_WEXT
52 	memset(&wrqu, 0, sizeof(wrqu));
53 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
54 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
55 #endif
56 }
57 
58 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp)
59 {
60 	struct wireless_dev *wdev = dev->ieee80211_ptr;
61 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
62 	struct cfg80211_event *ev;
63 	unsigned long flags;
64 
65 	trace_cfg80211_ibss_joined(dev, bssid);
66 
67 	CFG80211_DEV_WARN_ON(wdev->sme_state != CFG80211_SME_CONNECTING);
68 
69 	ev = kzalloc(sizeof(*ev), gfp);
70 	if (!ev)
71 		return;
72 
73 	ev->type = EVENT_IBSS_JOINED;
74 	memcpy(ev->cr.bssid, bssid, ETH_ALEN);
75 
76 	spin_lock_irqsave(&wdev->event_lock, flags);
77 	list_add_tail(&ev->list, &wdev->event_list);
78 	spin_unlock_irqrestore(&wdev->event_lock, flags);
79 	queue_work(cfg80211_wq, &rdev->event_work);
80 }
81 EXPORT_SYMBOL(cfg80211_ibss_joined);
82 
83 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
84 			 struct net_device *dev,
85 			 struct cfg80211_ibss_params *params,
86 			 struct cfg80211_cached_keys *connkeys)
87 {
88 	struct wireless_dev *wdev = dev->ieee80211_ptr;
89 	int err;
90 
91 	ASSERT_WDEV_LOCK(wdev);
92 
93 	if (wdev->ssid_len)
94 		return -EALREADY;
95 
96 	if (!params->basic_rates) {
97 		/*
98 		* If no rates were explicitly configured,
99 		* use the mandatory rate set for 11b or
100 		* 11a for maximum compatibility.
101 		*/
102 		struct ieee80211_supported_band *sband =
103 			rdev->wiphy.bands[params->chandef.chan->band];
104 		int j;
105 		u32 flag = params->chandef.chan->band == IEEE80211_BAND_5GHZ ?
106 			IEEE80211_RATE_MANDATORY_A :
107 			IEEE80211_RATE_MANDATORY_B;
108 
109 		for (j = 0; j < sband->n_bitrates; j++) {
110 			if (sband->bitrates[j].flags & flag)
111 				params->basic_rates |= BIT(j);
112 		}
113 	}
114 
115 	if (WARN_ON(wdev->connect_keys))
116 		kfree(wdev->connect_keys);
117 	wdev->connect_keys = connkeys;
118 
119 	wdev->ibss_fixed = params->channel_fixed;
120 #ifdef CONFIG_CFG80211_WEXT
121 	wdev->wext.ibss.chandef = params->chandef;
122 #endif
123 	wdev->sme_state = CFG80211_SME_CONNECTING;
124 
125 	err = cfg80211_can_use_chan(rdev, wdev, params->chandef.chan,
126 				    params->channel_fixed
127 				    ? CHAN_MODE_SHARED
128 				    : CHAN_MODE_EXCLUSIVE);
129 	if (err) {
130 		wdev->connect_keys = NULL;
131 		return err;
132 	}
133 
134 	err = rdev_join_ibss(rdev, dev, params);
135 	if (err) {
136 		wdev->connect_keys = NULL;
137 		wdev->sme_state = CFG80211_SME_IDLE;
138 		return err;
139 	}
140 
141 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
142 	wdev->ssid_len = params->ssid_len;
143 
144 	return 0;
145 }
146 
147 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
148 		       struct net_device *dev,
149 		       struct cfg80211_ibss_params *params,
150 		       struct cfg80211_cached_keys *connkeys)
151 {
152 	struct wireless_dev *wdev = dev->ieee80211_ptr;
153 	int err;
154 
155 	mutex_lock(&rdev->devlist_mtx);
156 	wdev_lock(wdev);
157 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
158 	wdev_unlock(wdev);
159 	mutex_unlock(&rdev->devlist_mtx);
160 
161 	return err;
162 }
163 
164 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
165 {
166 	struct wireless_dev *wdev = dev->ieee80211_ptr;
167 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
168 	int i;
169 
170 	ASSERT_WDEV_LOCK(wdev);
171 
172 	kfree(wdev->connect_keys);
173 	wdev->connect_keys = NULL;
174 
175 	/*
176 	 * Delete all the keys ... pairwise keys can't really
177 	 * exist any more anyway, but default keys might.
178 	 */
179 	if (rdev->ops->del_key)
180 		for (i = 0; i < 6; i++)
181 			rdev_del_key(rdev, dev, i, false, NULL);
182 
183 	if (wdev->current_bss) {
184 		cfg80211_unhold_bss(wdev->current_bss);
185 		cfg80211_put_bss(&wdev->current_bss->pub);
186 	}
187 
188 	wdev->current_bss = NULL;
189 	wdev->sme_state = CFG80211_SME_IDLE;
190 	wdev->ssid_len = 0;
191 #ifdef CONFIG_CFG80211_WEXT
192 	if (!nowext)
193 		wdev->wext.ibss.ssid_len = 0;
194 #endif
195 }
196 
197 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
198 {
199 	struct wireless_dev *wdev = dev->ieee80211_ptr;
200 
201 	wdev_lock(wdev);
202 	__cfg80211_clear_ibss(dev, nowext);
203 	wdev_unlock(wdev);
204 }
205 
206 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
207 			  struct net_device *dev, bool nowext)
208 {
209 	struct wireless_dev *wdev = dev->ieee80211_ptr;
210 	int err;
211 
212 	ASSERT_WDEV_LOCK(wdev);
213 
214 	if (!wdev->ssid_len)
215 		return -ENOLINK;
216 
217 	err = rdev_leave_ibss(rdev, dev);
218 
219 	if (err)
220 		return err;
221 
222 	__cfg80211_clear_ibss(dev, nowext);
223 
224 	return 0;
225 }
226 
227 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
228 			struct net_device *dev, bool nowext)
229 {
230 	struct wireless_dev *wdev = dev->ieee80211_ptr;
231 	int err;
232 
233 	wdev_lock(wdev);
234 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
235 	wdev_unlock(wdev);
236 
237 	return err;
238 }
239 
240 #ifdef CONFIG_CFG80211_WEXT
241 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
242 			    struct wireless_dev *wdev)
243 {
244 	struct cfg80211_cached_keys *ck = NULL;
245 	enum ieee80211_band band;
246 	int i, err;
247 
248 	ASSERT_WDEV_LOCK(wdev);
249 
250 	if (!wdev->wext.ibss.beacon_interval)
251 		wdev->wext.ibss.beacon_interval = 100;
252 
253 	/* try to find an IBSS channel if none requested ... */
254 	if (!wdev->wext.ibss.chandef.chan) {
255 		wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
256 
257 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
258 			struct ieee80211_supported_band *sband;
259 			struct ieee80211_channel *chan;
260 
261 			sband = rdev->wiphy.bands[band];
262 			if (!sband)
263 				continue;
264 
265 			for (i = 0; i < sband->n_channels; i++) {
266 				chan = &sband->channels[i];
267 				if (chan->flags & IEEE80211_CHAN_NO_IBSS)
268 					continue;
269 				if (chan->flags & IEEE80211_CHAN_DISABLED)
270 					continue;
271 				wdev->wext.ibss.chandef.chan = chan;
272 				break;
273 			}
274 
275 			if (wdev->wext.ibss.chandef.chan)
276 				break;
277 		}
278 
279 		if (!wdev->wext.ibss.chandef.chan)
280 			return -EINVAL;
281 	}
282 
283 	/* don't join -- SSID is not there */
284 	if (!wdev->wext.ibss.ssid_len)
285 		return 0;
286 
287 	if (!netif_running(wdev->netdev))
288 		return 0;
289 
290 	if (wdev->wext.keys) {
291 		wdev->wext.keys->def = wdev->wext.default_key;
292 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
293 	}
294 
295 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
296 
297 	if (wdev->wext.keys) {
298 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
299 		if (!ck)
300 			return -ENOMEM;
301 		for (i = 0; i < 6; i++)
302 			ck->params[i].key = ck->data[i];
303 	}
304 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
305 				   &wdev->wext.ibss, ck);
306 	if (err)
307 		kfree(ck);
308 
309 	return err;
310 }
311 
312 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
313 			       struct iw_request_info *info,
314 			       struct iw_freq *wextfreq, char *extra)
315 {
316 	struct wireless_dev *wdev = dev->ieee80211_ptr;
317 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
318 	struct ieee80211_channel *chan = NULL;
319 	int err, freq;
320 
321 	/* call only for ibss! */
322 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
323 		return -EINVAL;
324 
325 	if (!rdev->ops->join_ibss)
326 		return -EOPNOTSUPP;
327 
328 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
329 	if (freq < 0)
330 		return freq;
331 
332 	if (freq) {
333 		chan = ieee80211_get_channel(wdev->wiphy, freq);
334 		if (!chan)
335 			return -EINVAL;
336 		if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
337 		    chan->flags & IEEE80211_CHAN_DISABLED)
338 			return -EINVAL;
339 	}
340 
341 	if (wdev->wext.ibss.chandef.chan == chan)
342 		return 0;
343 
344 	wdev_lock(wdev);
345 	err = 0;
346 	if (wdev->ssid_len)
347 		err = __cfg80211_leave_ibss(rdev, dev, true);
348 	wdev_unlock(wdev);
349 
350 	if (err)
351 		return err;
352 
353 	if (chan) {
354 		wdev->wext.ibss.chandef.chan = chan;
355 		wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
356 		wdev->wext.ibss.channel_fixed = true;
357 	} else {
358 		/* cfg80211_ibss_wext_join will pick one if needed */
359 		wdev->wext.ibss.channel_fixed = false;
360 	}
361 
362 	mutex_lock(&rdev->devlist_mtx);
363 	wdev_lock(wdev);
364 	err = cfg80211_ibss_wext_join(rdev, wdev);
365 	wdev_unlock(wdev);
366 	mutex_unlock(&rdev->devlist_mtx);
367 
368 	return err;
369 }
370 
371 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
372 			       struct iw_request_info *info,
373 			       struct iw_freq *freq, char *extra)
374 {
375 	struct wireless_dev *wdev = dev->ieee80211_ptr;
376 	struct ieee80211_channel *chan = NULL;
377 
378 	/* call only for ibss! */
379 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
380 		return -EINVAL;
381 
382 	wdev_lock(wdev);
383 	if (wdev->current_bss)
384 		chan = wdev->current_bss->pub.channel;
385 	else if (wdev->wext.ibss.chandef.chan)
386 		chan = wdev->wext.ibss.chandef.chan;
387 	wdev_unlock(wdev);
388 
389 	if (chan) {
390 		freq->m = chan->center_freq;
391 		freq->e = 6;
392 		return 0;
393 	}
394 
395 	/* no channel if not joining */
396 	return -EINVAL;
397 }
398 
399 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
400 				struct iw_request_info *info,
401 				struct iw_point *data, char *ssid)
402 {
403 	struct wireless_dev *wdev = dev->ieee80211_ptr;
404 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
405 	size_t len = data->length;
406 	int err;
407 
408 	/* call only for ibss! */
409 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
410 		return -EINVAL;
411 
412 	if (!rdev->ops->join_ibss)
413 		return -EOPNOTSUPP;
414 
415 	wdev_lock(wdev);
416 	err = 0;
417 	if (wdev->ssid_len)
418 		err = __cfg80211_leave_ibss(rdev, dev, true);
419 	wdev_unlock(wdev);
420 
421 	if (err)
422 		return err;
423 
424 	/* iwconfig uses nul termination in SSID.. */
425 	if (len > 0 && ssid[len - 1] == '\0')
426 		len--;
427 
428 	wdev->wext.ibss.ssid = wdev->ssid;
429 	memcpy(wdev->wext.ibss.ssid, ssid, len);
430 	wdev->wext.ibss.ssid_len = len;
431 
432 	mutex_lock(&rdev->devlist_mtx);
433 	wdev_lock(wdev);
434 	err = cfg80211_ibss_wext_join(rdev, wdev);
435 	wdev_unlock(wdev);
436 	mutex_unlock(&rdev->devlist_mtx);
437 
438 	return err;
439 }
440 
441 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
442 				struct iw_request_info *info,
443 				struct iw_point *data, char *ssid)
444 {
445 	struct wireless_dev *wdev = dev->ieee80211_ptr;
446 
447 	/* call only for ibss! */
448 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
449 		return -EINVAL;
450 
451 	data->flags = 0;
452 
453 	wdev_lock(wdev);
454 	if (wdev->ssid_len) {
455 		data->flags = 1;
456 		data->length = wdev->ssid_len;
457 		memcpy(ssid, wdev->ssid, data->length);
458 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
459 		data->flags = 1;
460 		data->length = wdev->wext.ibss.ssid_len;
461 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
462 	}
463 	wdev_unlock(wdev);
464 
465 	return 0;
466 }
467 
468 int cfg80211_ibss_wext_siwap(struct net_device *dev,
469 			     struct iw_request_info *info,
470 			     struct sockaddr *ap_addr, char *extra)
471 {
472 	struct wireless_dev *wdev = dev->ieee80211_ptr;
473 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
474 	u8 *bssid = ap_addr->sa_data;
475 	int err;
476 
477 	/* call only for ibss! */
478 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
479 		return -EINVAL;
480 
481 	if (!rdev->ops->join_ibss)
482 		return -EOPNOTSUPP;
483 
484 	if (ap_addr->sa_family != ARPHRD_ETHER)
485 		return -EINVAL;
486 
487 	/* automatic mode */
488 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
489 		bssid = NULL;
490 
491 	/* both automatic */
492 	if (!bssid && !wdev->wext.ibss.bssid)
493 		return 0;
494 
495 	/* fixed already - and no change */
496 	if (wdev->wext.ibss.bssid && bssid &&
497 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
498 		return 0;
499 
500 	wdev_lock(wdev);
501 	err = 0;
502 	if (wdev->ssid_len)
503 		err = __cfg80211_leave_ibss(rdev, dev, true);
504 	wdev_unlock(wdev);
505 
506 	if (err)
507 		return err;
508 
509 	if (bssid) {
510 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
511 		wdev->wext.ibss.bssid = wdev->wext.bssid;
512 	} else
513 		wdev->wext.ibss.bssid = NULL;
514 
515 	mutex_lock(&rdev->devlist_mtx);
516 	wdev_lock(wdev);
517 	err = cfg80211_ibss_wext_join(rdev, wdev);
518 	wdev_unlock(wdev);
519 	mutex_unlock(&rdev->devlist_mtx);
520 
521 	return err;
522 }
523 
524 int cfg80211_ibss_wext_giwap(struct net_device *dev,
525 			     struct iw_request_info *info,
526 			     struct sockaddr *ap_addr, char *extra)
527 {
528 	struct wireless_dev *wdev = dev->ieee80211_ptr;
529 
530 	/* call only for ibss! */
531 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
532 		return -EINVAL;
533 
534 	ap_addr->sa_family = ARPHRD_ETHER;
535 
536 	wdev_lock(wdev);
537 	if (wdev->current_bss)
538 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
539 	else if (wdev->wext.ibss.bssid)
540 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
541 	else
542 		memset(ap_addr->sa_data, 0, ETH_ALEN);
543 
544 	wdev_unlock(wdev);
545 
546 	return 0;
547 }
548 #endif
549