xref: /linux/net/wireless/ibss.c (revision a33f32244d8550da8b4a26e277ce07d5c6d158b5)
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 <net/cfg80211.h>
11 #include "wext-compat.h"
12 #include "nl80211.h"
13 
14 
15 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid)
16 {
17 	struct wireless_dev *wdev = dev->ieee80211_ptr;
18 	struct cfg80211_bss *bss;
19 #ifdef CONFIG_CFG80211_WEXT
20 	union iwreq_data wrqu;
21 #endif
22 
23 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
24 		return;
25 
26 	if (!wdev->ssid_len)
27 		return;
28 
29 	bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid,
30 			       wdev->ssid, wdev->ssid_len,
31 			       WLAN_CAPABILITY_IBSS, WLAN_CAPABILITY_IBSS);
32 
33 	if (WARN_ON(!bss))
34 		return;
35 
36 	if (wdev->current_bss) {
37 		cfg80211_unhold_bss(wdev->current_bss);
38 		cfg80211_put_bss(&wdev->current_bss->pub);
39 	}
40 
41 	cfg80211_hold_bss(bss_from_pub(bss));
42 	wdev->current_bss = bss_from_pub(bss);
43 
44 	cfg80211_upload_connect_keys(wdev);
45 
46 	nl80211_send_ibss_bssid(wiphy_to_dev(wdev->wiphy), dev, bssid,
47 				GFP_KERNEL);
48 #ifdef CONFIG_CFG80211_WEXT
49 	memset(&wrqu, 0, sizeof(wrqu));
50 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
51 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
52 #endif
53 }
54 
55 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp)
56 {
57 	struct wireless_dev *wdev = dev->ieee80211_ptr;
58 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
59 	struct cfg80211_event *ev;
60 	unsigned long flags;
61 
62 	CFG80211_DEV_WARN_ON(!wdev->ssid_len);
63 
64 	ev = kzalloc(sizeof(*ev), gfp);
65 	if (!ev)
66 		return;
67 
68 	ev->type = EVENT_IBSS_JOINED;
69 	memcpy(ev->cr.bssid, bssid, ETH_ALEN);
70 
71 	spin_lock_irqsave(&wdev->event_lock, flags);
72 	list_add_tail(&ev->list, &wdev->event_list);
73 	spin_unlock_irqrestore(&wdev->event_lock, flags);
74 	queue_work(cfg80211_wq, &rdev->event_work);
75 }
76 EXPORT_SYMBOL(cfg80211_ibss_joined);
77 
78 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
79 			 struct net_device *dev,
80 			 struct cfg80211_ibss_params *params,
81 			 struct cfg80211_cached_keys *connkeys)
82 {
83 	struct wireless_dev *wdev = dev->ieee80211_ptr;
84 	struct ieee80211_channel *chan;
85 	int err;
86 
87 	ASSERT_WDEV_LOCK(wdev);
88 
89 	chan = rdev_fixed_channel(rdev, wdev);
90 	if (chan && chan != params->channel)
91 		return -EBUSY;
92 
93 	if (wdev->ssid_len)
94 		return -EALREADY;
95 
96 	if (WARN_ON(wdev->connect_keys))
97 		kfree(wdev->connect_keys);
98 	wdev->connect_keys = connkeys;
99 
100 #ifdef CONFIG_CFG80211_WEXT
101 	wdev->wext.ibss.channel = params->channel;
102 #endif
103 	err = rdev->ops->join_ibss(&rdev->wiphy, dev, params);
104 	if (err) {
105 		wdev->connect_keys = NULL;
106 		return err;
107 	}
108 
109 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
110 	wdev->ssid_len = params->ssid_len;
111 
112 	return 0;
113 }
114 
115 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
116 		       struct net_device *dev,
117 		       struct cfg80211_ibss_params *params,
118 		       struct cfg80211_cached_keys *connkeys)
119 {
120 	struct wireless_dev *wdev = dev->ieee80211_ptr;
121 	int err;
122 
123 	mutex_lock(&rdev->devlist_mtx);
124 	wdev_lock(wdev);
125 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
126 	wdev_unlock(wdev);
127 	mutex_unlock(&rdev->devlist_mtx);
128 
129 	return err;
130 }
131 
132 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
133 {
134 	struct wireless_dev *wdev = dev->ieee80211_ptr;
135 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
136 	int i;
137 
138 	ASSERT_WDEV_LOCK(wdev);
139 
140 	kfree(wdev->connect_keys);
141 	wdev->connect_keys = NULL;
142 
143 	/*
144 	 * Delete all the keys ... pairwise keys can't really
145 	 * exist any more anyway, but default keys might.
146 	 */
147 	if (rdev->ops->del_key)
148 		for (i = 0; i < 6; i++)
149 			rdev->ops->del_key(wdev->wiphy, dev, i, NULL);
150 
151 	if (wdev->current_bss) {
152 		cfg80211_unhold_bss(wdev->current_bss);
153 		cfg80211_put_bss(&wdev->current_bss->pub);
154 	}
155 
156 	wdev->current_bss = NULL;
157 	wdev->ssid_len = 0;
158 #ifdef CONFIG_CFG80211_WEXT
159 	if (!nowext)
160 		wdev->wext.ibss.ssid_len = 0;
161 #endif
162 }
163 
164 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
165 {
166 	struct wireless_dev *wdev = dev->ieee80211_ptr;
167 
168 	wdev_lock(wdev);
169 	__cfg80211_clear_ibss(dev, nowext);
170 	wdev_unlock(wdev);
171 }
172 
173 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
174 			  struct net_device *dev, bool nowext)
175 {
176 	struct wireless_dev *wdev = dev->ieee80211_ptr;
177 	int err;
178 
179 	ASSERT_WDEV_LOCK(wdev);
180 
181 	if (!wdev->ssid_len)
182 		return -ENOLINK;
183 
184 	err = rdev->ops->leave_ibss(&rdev->wiphy, dev);
185 
186 	if (err)
187 		return err;
188 
189 	__cfg80211_clear_ibss(dev, nowext);
190 
191 	return 0;
192 }
193 
194 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
195 			struct net_device *dev, bool nowext)
196 {
197 	struct wireless_dev *wdev = dev->ieee80211_ptr;
198 	int err;
199 
200 	wdev_lock(wdev);
201 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
202 	wdev_unlock(wdev);
203 
204 	return err;
205 }
206 
207 #ifdef CONFIG_CFG80211_WEXT
208 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
209 			    struct wireless_dev *wdev)
210 {
211 	struct cfg80211_cached_keys *ck = NULL;
212 	enum ieee80211_band band;
213 	int i, err;
214 
215 	ASSERT_WDEV_LOCK(wdev);
216 
217 	if (!wdev->wext.ibss.beacon_interval)
218 		wdev->wext.ibss.beacon_interval = 100;
219 
220 	/* try to find an IBSS channel if none requested ... */
221 	if (!wdev->wext.ibss.channel) {
222 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
223 			struct ieee80211_supported_band *sband;
224 			struct ieee80211_channel *chan;
225 
226 			sband = rdev->wiphy.bands[band];
227 			if (!sband)
228 				continue;
229 
230 			for (i = 0; i < sband->n_channels; i++) {
231 				chan = &sband->channels[i];
232 				if (chan->flags & IEEE80211_CHAN_NO_IBSS)
233 					continue;
234 				if (chan->flags & IEEE80211_CHAN_DISABLED)
235 					continue;
236 				wdev->wext.ibss.channel = chan;
237 				break;
238 			}
239 
240 			if (wdev->wext.ibss.channel)
241 				break;
242 		}
243 
244 		if (!wdev->wext.ibss.channel)
245 			return -EINVAL;
246 	}
247 
248 	/* don't join -- SSID is not there */
249 	if (!wdev->wext.ibss.ssid_len)
250 		return 0;
251 
252 	if (!netif_running(wdev->netdev))
253 		return 0;
254 
255 	if (wdev->wext.keys)
256 		wdev->wext.keys->def = wdev->wext.default_key;
257 
258 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
259 
260 	if (wdev->wext.keys) {
261 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
262 		if (!ck)
263 			return -ENOMEM;
264 		for (i = 0; i < 6; i++)
265 			ck->params[i].key = ck->data[i];
266 	}
267 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
268 				   &wdev->wext.ibss, ck);
269 	if (err)
270 		kfree(ck);
271 
272 	return err;
273 }
274 
275 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
276 			       struct iw_request_info *info,
277 			       struct iw_freq *wextfreq, char *extra)
278 {
279 	struct wireless_dev *wdev = dev->ieee80211_ptr;
280 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
281 	struct ieee80211_channel *chan = NULL;
282 	int err, freq;
283 
284 	/* call only for ibss! */
285 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
286 		return -EINVAL;
287 
288 	if (!rdev->ops->join_ibss)
289 		return -EOPNOTSUPP;
290 
291 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
292 	if (freq < 0)
293 		return freq;
294 
295 	if (freq) {
296 		chan = ieee80211_get_channel(wdev->wiphy, freq);
297 		if (!chan)
298 			return -EINVAL;
299 		if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
300 		    chan->flags & IEEE80211_CHAN_DISABLED)
301 			return -EINVAL;
302 	}
303 
304 	if (wdev->wext.ibss.channel == chan)
305 		return 0;
306 
307 	wdev_lock(wdev);
308 	err = 0;
309 	if (wdev->ssid_len)
310 		err = __cfg80211_leave_ibss(rdev, dev, true);
311 	wdev_unlock(wdev);
312 
313 	if (err)
314 		return err;
315 
316 	if (chan) {
317 		wdev->wext.ibss.channel = chan;
318 		wdev->wext.ibss.channel_fixed = true;
319 	} else {
320 		/* cfg80211_ibss_wext_join will pick one if needed */
321 		wdev->wext.ibss.channel_fixed = false;
322 	}
323 
324 	mutex_lock(&rdev->devlist_mtx);
325 	wdev_lock(wdev);
326 	err = cfg80211_ibss_wext_join(rdev, wdev);
327 	wdev_unlock(wdev);
328 	mutex_unlock(&rdev->devlist_mtx);
329 
330 	return err;
331 }
332 
333 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
334 			       struct iw_request_info *info,
335 			       struct iw_freq *freq, char *extra)
336 {
337 	struct wireless_dev *wdev = dev->ieee80211_ptr;
338 	struct ieee80211_channel *chan = NULL;
339 
340 	/* call only for ibss! */
341 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
342 		return -EINVAL;
343 
344 	wdev_lock(wdev);
345 	if (wdev->current_bss)
346 		chan = wdev->current_bss->pub.channel;
347 	else if (wdev->wext.ibss.channel)
348 		chan = wdev->wext.ibss.channel;
349 	wdev_unlock(wdev);
350 
351 	if (chan) {
352 		freq->m = chan->center_freq;
353 		freq->e = 6;
354 		return 0;
355 	}
356 
357 	/* no channel if not joining */
358 	return -EINVAL;
359 }
360 
361 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
362 				struct iw_request_info *info,
363 				struct iw_point *data, char *ssid)
364 {
365 	struct wireless_dev *wdev = dev->ieee80211_ptr;
366 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
367 	size_t len = data->length;
368 	int err;
369 
370 	/* call only for ibss! */
371 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
372 		return -EINVAL;
373 
374 	if (!rdev->ops->join_ibss)
375 		return -EOPNOTSUPP;
376 
377 	wdev_lock(wdev);
378 	err = 0;
379 	if (wdev->ssid_len)
380 		err = __cfg80211_leave_ibss(rdev, dev, true);
381 	wdev_unlock(wdev);
382 
383 	if (err)
384 		return err;
385 
386 	/* iwconfig uses nul termination in SSID.. */
387 	if (len > 0 && ssid[len - 1] == '\0')
388 		len--;
389 
390 	wdev->wext.ibss.ssid = wdev->ssid;
391 	memcpy(wdev->wext.ibss.ssid, ssid, len);
392 	wdev->wext.ibss.ssid_len = len;
393 
394 	mutex_lock(&rdev->devlist_mtx);
395 	wdev_lock(wdev);
396 	err = cfg80211_ibss_wext_join(rdev, wdev);
397 	wdev_unlock(wdev);
398 	mutex_unlock(&rdev->devlist_mtx);
399 
400 	return err;
401 }
402 
403 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
404 				struct iw_request_info *info,
405 				struct iw_point *data, char *ssid)
406 {
407 	struct wireless_dev *wdev = dev->ieee80211_ptr;
408 
409 	/* call only for ibss! */
410 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
411 		return -EINVAL;
412 
413 	data->flags = 0;
414 
415 	wdev_lock(wdev);
416 	if (wdev->ssid_len) {
417 		data->flags = 1;
418 		data->length = wdev->ssid_len;
419 		memcpy(ssid, wdev->ssid, data->length);
420 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
421 		data->flags = 1;
422 		data->length = wdev->wext.ibss.ssid_len;
423 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
424 	}
425 	wdev_unlock(wdev);
426 
427 	return 0;
428 }
429 
430 int cfg80211_ibss_wext_siwap(struct net_device *dev,
431 			     struct iw_request_info *info,
432 			     struct sockaddr *ap_addr, char *extra)
433 {
434 	struct wireless_dev *wdev = dev->ieee80211_ptr;
435 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
436 	u8 *bssid = ap_addr->sa_data;
437 	int err;
438 
439 	/* call only for ibss! */
440 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
441 		return -EINVAL;
442 
443 	if (!rdev->ops->join_ibss)
444 		return -EOPNOTSUPP;
445 
446 	if (ap_addr->sa_family != ARPHRD_ETHER)
447 		return -EINVAL;
448 
449 	/* automatic mode */
450 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
451 		bssid = NULL;
452 
453 	/* both automatic */
454 	if (!bssid && !wdev->wext.ibss.bssid)
455 		return 0;
456 
457 	/* fixed already - and no change */
458 	if (wdev->wext.ibss.bssid && bssid &&
459 	    compare_ether_addr(bssid, wdev->wext.ibss.bssid) == 0)
460 		return 0;
461 
462 	wdev_lock(wdev);
463 	err = 0;
464 	if (wdev->ssid_len)
465 		err = __cfg80211_leave_ibss(rdev, dev, true);
466 	wdev_unlock(wdev);
467 
468 	if (err)
469 		return err;
470 
471 	if (bssid) {
472 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
473 		wdev->wext.ibss.bssid = wdev->wext.bssid;
474 	} else
475 		wdev->wext.ibss.bssid = NULL;
476 
477 	mutex_lock(&rdev->devlist_mtx);
478 	wdev_lock(wdev);
479 	err = cfg80211_ibss_wext_join(rdev, wdev);
480 	wdev_unlock(wdev);
481 	mutex_unlock(&rdev->devlist_mtx);
482 
483 	return err;
484 }
485 
486 int cfg80211_ibss_wext_giwap(struct net_device *dev,
487 			     struct iw_request_info *info,
488 			     struct sockaddr *ap_addr, char *extra)
489 {
490 	struct wireless_dev *wdev = dev->ieee80211_ptr;
491 
492 	/* call only for ibss! */
493 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
494 		return -EINVAL;
495 
496 	ap_addr->sa_family = ARPHRD_ETHER;
497 
498 	wdev_lock(wdev);
499 	if (wdev->current_bss)
500 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
501 	else if (wdev->wext.ibss.bssid)
502 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
503 	else
504 		memset(ap_addr->sa_data, 0, ETH_ALEN);
505 
506 	wdev_unlock(wdev);
507 
508 	return 0;
509 }
510 #endif
511