xref: /linux/net/wireless/ibss.c (revision 6fa79bcaecdbb0eb417afbc7fb0a8fa204308b62)
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 
15 
16 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid)
17 {
18 	struct wireless_dev *wdev = dev->ieee80211_ptr;
19 	struct cfg80211_bss *bss;
20 #ifdef CONFIG_CFG80211_WEXT
21 	union iwreq_data wrqu;
22 #endif
23 
24 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
25 		return;
26 
27 	if (!wdev->ssid_len)
28 		return;
29 
30 	bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid,
31 			       wdev->ssid, wdev->ssid_len,
32 			       WLAN_CAPABILITY_IBSS, WLAN_CAPABILITY_IBSS);
33 
34 	if (WARN_ON(!bss))
35 		return;
36 
37 	if (wdev->current_bss) {
38 		cfg80211_unhold_bss(wdev->current_bss);
39 		cfg80211_put_bss(&wdev->current_bss->pub);
40 	}
41 
42 	cfg80211_hold_bss(bss_from_pub(bss));
43 	wdev->current_bss = bss_from_pub(bss);
44 
45 	wdev->sme_state = CFG80211_SME_CONNECTED;
46 	cfg80211_upload_connect_keys(wdev);
47 
48 	nl80211_send_ibss_bssid(wiphy_to_dev(wdev->wiphy), dev, bssid,
49 				GFP_KERNEL);
50 #ifdef CONFIG_CFG80211_WEXT
51 	memset(&wrqu, 0, sizeof(wrqu));
52 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
53 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
54 #endif
55 }
56 
57 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid, gfp_t gfp)
58 {
59 	struct wireless_dev *wdev = dev->ieee80211_ptr;
60 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
61 	struct cfg80211_event *ev;
62 	unsigned long flags;
63 
64 	CFG80211_DEV_WARN_ON(wdev->sme_state != CFG80211_SME_CONNECTING);
65 
66 	ev = kzalloc(sizeof(*ev), gfp);
67 	if (!ev)
68 		return;
69 
70 	ev->type = EVENT_IBSS_JOINED;
71 	memcpy(ev->cr.bssid, bssid, ETH_ALEN);
72 
73 	spin_lock_irqsave(&wdev->event_lock, flags);
74 	list_add_tail(&ev->list, &wdev->event_list);
75 	spin_unlock_irqrestore(&wdev->event_lock, flags);
76 	queue_work(cfg80211_wq, &rdev->event_work);
77 }
78 EXPORT_SYMBOL(cfg80211_ibss_joined);
79 
80 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
81 			 struct net_device *dev,
82 			 struct cfg80211_ibss_params *params,
83 			 struct cfg80211_cached_keys *connkeys)
84 {
85 	struct wireless_dev *wdev = dev->ieee80211_ptr;
86 	int err;
87 
88 	ASSERT_WDEV_LOCK(wdev);
89 
90 	if (wdev->ssid_len)
91 		return -EALREADY;
92 
93 	if (!params->basic_rates) {
94 		/*
95 		* If no rates were explicitly configured,
96 		* use the mandatory rate set for 11b or
97 		* 11a for maximum compatibility.
98 		*/
99 		struct ieee80211_supported_band *sband =
100 			rdev->wiphy.bands[params->channel->band];
101 		int j;
102 		u32 flag = params->channel->band == IEEE80211_BAND_5GHZ ?
103 			IEEE80211_RATE_MANDATORY_A :
104 			IEEE80211_RATE_MANDATORY_B;
105 
106 		for (j = 0; j < sband->n_bitrates; j++) {
107 			if (sband->bitrates[j].flags & flag)
108 				params->basic_rates |= BIT(j);
109 		}
110 	}
111 
112 	if (WARN_ON(wdev->connect_keys))
113 		kfree(wdev->connect_keys);
114 	wdev->connect_keys = connkeys;
115 
116 	wdev->ibss_fixed = params->channel_fixed;
117 #ifdef CONFIG_CFG80211_WEXT
118 	wdev->wext.ibss.channel = params->channel;
119 #endif
120 	wdev->sme_state = CFG80211_SME_CONNECTING;
121 
122 	err = cfg80211_can_use_chan(rdev, wdev, params->channel,
123 				    params->channel_fixed
124 				    ? CHAN_MODE_SHARED
125 				    : CHAN_MODE_EXCLUSIVE);
126 	if (err) {
127 		wdev->connect_keys = NULL;
128 		return err;
129 	}
130 
131 	err = rdev->ops->join_ibss(&rdev->wiphy, dev, params);
132 	if (err) {
133 		wdev->connect_keys = NULL;
134 		wdev->sme_state = CFG80211_SME_IDLE;
135 		return err;
136 	}
137 
138 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
139 	wdev->ssid_len = params->ssid_len;
140 
141 	return 0;
142 }
143 
144 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
145 		       struct net_device *dev,
146 		       struct cfg80211_ibss_params *params,
147 		       struct cfg80211_cached_keys *connkeys)
148 {
149 	struct wireless_dev *wdev = dev->ieee80211_ptr;
150 	int err;
151 
152 	mutex_lock(&rdev->devlist_mtx);
153 	wdev_lock(wdev);
154 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
155 	wdev_unlock(wdev);
156 	mutex_unlock(&rdev->devlist_mtx);
157 
158 	return err;
159 }
160 
161 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
162 {
163 	struct wireless_dev *wdev = dev->ieee80211_ptr;
164 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
165 	int i;
166 
167 	ASSERT_WDEV_LOCK(wdev);
168 
169 	kfree(wdev->connect_keys);
170 	wdev->connect_keys = NULL;
171 
172 	/*
173 	 * Delete all the keys ... pairwise keys can't really
174 	 * exist any more anyway, but default keys might.
175 	 */
176 	if (rdev->ops->del_key)
177 		for (i = 0; i < 6; i++)
178 			rdev->ops->del_key(wdev->wiphy, dev, i, false, NULL);
179 
180 	if (wdev->current_bss) {
181 		cfg80211_unhold_bss(wdev->current_bss);
182 		cfg80211_put_bss(&wdev->current_bss->pub);
183 	}
184 
185 	wdev->current_bss = NULL;
186 	wdev->sme_state = CFG80211_SME_IDLE;
187 	wdev->ssid_len = 0;
188 #ifdef CONFIG_CFG80211_WEXT
189 	if (!nowext)
190 		wdev->wext.ibss.ssid_len = 0;
191 #endif
192 }
193 
194 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
195 {
196 	struct wireless_dev *wdev = dev->ieee80211_ptr;
197 
198 	wdev_lock(wdev);
199 	__cfg80211_clear_ibss(dev, nowext);
200 	wdev_unlock(wdev);
201 }
202 
203 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
204 			  struct net_device *dev, bool nowext)
205 {
206 	struct wireless_dev *wdev = dev->ieee80211_ptr;
207 	int err;
208 
209 	ASSERT_WDEV_LOCK(wdev);
210 
211 	if (!wdev->ssid_len)
212 		return -ENOLINK;
213 
214 	err = rdev->ops->leave_ibss(&rdev->wiphy, dev);
215 
216 	if (err)
217 		return err;
218 
219 	__cfg80211_clear_ibss(dev, nowext);
220 
221 	return 0;
222 }
223 
224 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
225 			struct net_device *dev, bool nowext)
226 {
227 	struct wireless_dev *wdev = dev->ieee80211_ptr;
228 	int err;
229 
230 	wdev_lock(wdev);
231 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
232 	wdev_unlock(wdev);
233 
234 	return err;
235 }
236 
237 #ifdef CONFIG_CFG80211_WEXT
238 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
239 			    struct wireless_dev *wdev)
240 {
241 	struct cfg80211_cached_keys *ck = NULL;
242 	enum ieee80211_band band;
243 	int i, err;
244 
245 	ASSERT_WDEV_LOCK(wdev);
246 
247 	if (!wdev->wext.ibss.beacon_interval)
248 		wdev->wext.ibss.beacon_interval = 100;
249 
250 	/* try to find an IBSS channel if none requested ... */
251 	if (!wdev->wext.ibss.channel) {
252 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
253 			struct ieee80211_supported_band *sband;
254 			struct ieee80211_channel *chan;
255 
256 			sband = rdev->wiphy.bands[band];
257 			if (!sband)
258 				continue;
259 
260 			for (i = 0; i < sband->n_channels; i++) {
261 				chan = &sband->channels[i];
262 				if (chan->flags & IEEE80211_CHAN_NO_IBSS)
263 					continue;
264 				if (chan->flags & IEEE80211_CHAN_DISABLED)
265 					continue;
266 				wdev->wext.ibss.channel = chan;
267 				break;
268 			}
269 
270 			if (wdev->wext.ibss.channel)
271 				break;
272 		}
273 
274 		if (!wdev->wext.ibss.channel)
275 			return -EINVAL;
276 	}
277 
278 	/* don't join -- SSID is not there */
279 	if (!wdev->wext.ibss.ssid_len)
280 		return 0;
281 
282 	if (!netif_running(wdev->netdev))
283 		return 0;
284 
285 	if (wdev->wext.keys) {
286 		wdev->wext.keys->def = wdev->wext.default_key;
287 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
288 	}
289 
290 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
291 
292 	if (wdev->wext.keys) {
293 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
294 		if (!ck)
295 			return -ENOMEM;
296 		for (i = 0; i < 6; i++)
297 			ck->params[i].key = ck->data[i];
298 	}
299 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
300 				   &wdev->wext.ibss, ck);
301 	if (err)
302 		kfree(ck);
303 
304 	return err;
305 }
306 
307 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
308 			       struct iw_request_info *info,
309 			       struct iw_freq *wextfreq, char *extra)
310 {
311 	struct wireless_dev *wdev = dev->ieee80211_ptr;
312 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
313 	struct ieee80211_channel *chan = NULL;
314 	int err, freq;
315 
316 	/* call only for ibss! */
317 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
318 		return -EINVAL;
319 
320 	if (!rdev->ops->join_ibss)
321 		return -EOPNOTSUPP;
322 
323 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
324 	if (freq < 0)
325 		return freq;
326 
327 	if (freq) {
328 		chan = ieee80211_get_channel(wdev->wiphy, freq);
329 		if (!chan)
330 			return -EINVAL;
331 		if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
332 		    chan->flags & IEEE80211_CHAN_DISABLED)
333 			return -EINVAL;
334 	}
335 
336 	if (wdev->wext.ibss.channel == chan)
337 		return 0;
338 
339 	wdev_lock(wdev);
340 	err = 0;
341 	if (wdev->ssid_len)
342 		err = __cfg80211_leave_ibss(rdev, dev, true);
343 	wdev_unlock(wdev);
344 
345 	if (err)
346 		return err;
347 
348 	if (chan) {
349 		wdev->wext.ibss.channel = chan;
350 		wdev->wext.ibss.channel_fixed = true;
351 	} else {
352 		/* cfg80211_ibss_wext_join will pick one if needed */
353 		wdev->wext.ibss.channel_fixed = false;
354 	}
355 
356 	mutex_lock(&rdev->devlist_mtx);
357 	wdev_lock(wdev);
358 	err = cfg80211_ibss_wext_join(rdev, wdev);
359 	wdev_unlock(wdev);
360 	mutex_unlock(&rdev->devlist_mtx);
361 
362 	return err;
363 }
364 
365 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
366 			       struct iw_request_info *info,
367 			       struct iw_freq *freq, char *extra)
368 {
369 	struct wireless_dev *wdev = dev->ieee80211_ptr;
370 	struct ieee80211_channel *chan = NULL;
371 
372 	/* call only for ibss! */
373 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
374 		return -EINVAL;
375 
376 	wdev_lock(wdev);
377 	if (wdev->current_bss)
378 		chan = wdev->current_bss->pub.channel;
379 	else if (wdev->wext.ibss.channel)
380 		chan = wdev->wext.ibss.channel;
381 	wdev_unlock(wdev);
382 
383 	if (chan) {
384 		freq->m = chan->center_freq;
385 		freq->e = 6;
386 		return 0;
387 	}
388 
389 	/* no channel if not joining */
390 	return -EINVAL;
391 }
392 
393 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
394 				struct iw_request_info *info,
395 				struct iw_point *data, char *ssid)
396 {
397 	struct wireless_dev *wdev = dev->ieee80211_ptr;
398 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
399 	size_t len = data->length;
400 	int err;
401 
402 	/* call only for ibss! */
403 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
404 		return -EINVAL;
405 
406 	if (!rdev->ops->join_ibss)
407 		return -EOPNOTSUPP;
408 
409 	wdev_lock(wdev);
410 	err = 0;
411 	if (wdev->ssid_len)
412 		err = __cfg80211_leave_ibss(rdev, dev, true);
413 	wdev_unlock(wdev);
414 
415 	if (err)
416 		return err;
417 
418 	/* iwconfig uses nul termination in SSID.. */
419 	if (len > 0 && ssid[len - 1] == '\0')
420 		len--;
421 
422 	wdev->wext.ibss.ssid = wdev->ssid;
423 	memcpy(wdev->wext.ibss.ssid, ssid, len);
424 	wdev->wext.ibss.ssid_len = len;
425 
426 	mutex_lock(&rdev->devlist_mtx);
427 	wdev_lock(wdev);
428 	err = cfg80211_ibss_wext_join(rdev, wdev);
429 	wdev_unlock(wdev);
430 	mutex_unlock(&rdev->devlist_mtx);
431 
432 	return err;
433 }
434 
435 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
436 				struct iw_request_info *info,
437 				struct iw_point *data, char *ssid)
438 {
439 	struct wireless_dev *wdev = dev->ieee80211_ptr;
440 
441 	/* call only for ibss! */
442 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
443 		return -EINVAL;
444 
445 	data->flags = 0;
446 
447 	wdev_lock(wdev);
448 	if (wdev->ssid_len) {
449 		data->flags = 1;
450 		data->length = wdev->ssid_len;
451 		memcpy(ssid, wdev->ssid, data->length);
452 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
453 		data->flags = 1;
454 		data->length = wdev->wext.ibss.ssid_len;
455 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
456 	}
457 	wdev_unlock(wdev);
458 
459 	return 0;
460 }
461 
462 int cfg80211_ibss_wext_siwap(struct net_device *dev,
463 			     struct iw_request_info *info,
464 			     struct sockaddr *ap_addr, char *extra)
465 {
466 	struct wireless_dev *wdev = dev->ieee80211_ptr;
467 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
468 	u8 *bssid = ap_addr->sa_data;
469 	int err;
470 
471 	/* call only for ibss! */
472 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
473 		return -EINVAL;
474 
475 	if (!rdev->ops->join_ibss)
476 		return -EOPNOTSUPP;
477 
478 	if (ap_addr->sa_family != ARPHRD_ETHER)
479 		return -EINVAL;
480 
481 	/* automatic mode */
482 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
483 		bssid = NULL;
484 
485 	/* both automatic */
486 	if (!bssid && !wdev->wext.ibss.bssid)
487 		return 0;
488 
489 	/* fixed already - and no change */
490 	if (wdev->wext.ibss.bssid && bssid &&
491 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
492 		return 0;
493 
494 	wdev_lock(wdev);
495 	err = 0;
496 	if (wdev->ssid_len)
497 		err = __cfg80211_leave_ibss(rdev, dev, true);
498 	wdev_unlock(wdev);
499 
500 	if (err)
501 		return err;
502 
503 	if (bssid) {
504 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
505 		wdev->wext.ibss.bssid = wdev->wext.bssid;
506 	} else
507 		wdev->wext.ibss.bssid = NULL;
508 
509 	mutex_lock(&rdev->devlist_mtx);
510 	wdev_lock(wdev);
511 	err = cfg80211_ibss_wext_join(rdev, wdev);
512 	wdev_unlock(wdev);
513 	mutex_unlock(&rdev->devlist_mtx);
514 
515 	return err;
516 }
517 
518 int cfg80211_ibss_wext_giwap(struct net_device *dev,
519 			     struct iw_request_info *info,
520 			     struct sockaddr *ap_addr, char *extra)
521 {
522 	struct wireless_dev *wdev = dev->ieee80211_ptr;
523 
524 	/* call only for ibss! */
525 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
526 		return -EINVAL;
527 
528 	ap_addr->sa_family = ARPHRD_ETHER;
529 
530 	wdev_lock(wdev);
531 	if (wdev->current_bss)
532 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
533 	else if (wdev->wext.ibss.bssid)
534 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
535 	else
536 		memset(ap_addr->sa_data, 0, ETH_ALEN);
537 
538 	wdev_unlock(wdev);
539 
540 	return 0;
541 }
542 #endif
543