xref: /openbmc/linux/net/wireless/ibss.c (revision 12eb4683)
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->wiphy, &wdev->current_bss->pub);
41 	}
42 
43 	cfg80211_hold_bss(bss_from_pub(bss));
44 	wdev->current_bss = bss_from_pub(bss);
45 
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 	trace_cfg80211_ibss_joined(dev, bssid);
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 	struct ieee80211_channel *check_chan;
87 	u8 radar_detect_width = 0;
88 	int err;
89 
90 	ASSERT_WDEV_LOCK(wdev);
91 
92 	if (wdev->ssid_len)
93 		return -EALREADY;
94 
95 	if (!params->basic_rates) {
96 		/*
97 		* If no rates were explicitly configured,
98 		* use the mandatory rate set for 11b or
99 		* 11a for maximum compatibility.
100 		*/
101 		struct ieee80211_supported_band *sband =
102 			rdev->wiphy.bands[params->chandef.chan->band];
103 		int j;
104 		u32 flag = params->chandef.chan->band == IEEE80211_BAND_5GHZ ?
105 			IEEE80211_RATE_MANDATORY_A :
106 			IEEE80211_RATE_MANDATORY_B;
107 
108 		for (j = 0; j < sband->n_bitrates; j++) {
109 			if (sband->bitrates[j].flags & flag)
110 				params->basic_rates |= BIT(j);
111 		}
112 	}
113 
114 	if (WARN_ON(wdev->connect_keys))
115 		kfree(wdev->connect_keys);
116 	wdev->connect_keys = connkeys;
117 
118 	wdev->ibss_fixed = params->channel_fixed;
119 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
120 #ifdef CONFIG_CFG80211_WEXT
121 	wdev->wext.ibss.chandef = params->chandef;
122 #endif
123 	check_chan = params->chandef.chan;
124 	if (params->userspace_handles_dfs) {
125 		/* use channel NULL to check for radar even if the current
126 		 * channel is not a radar channel - it might decide to change
127 		 * to DFS channel later.
128 		 */
129 		radar_detect_width = BIT(params->chandef.width);
130 		check_chan = NULL;
131 	}
132 
133 	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
134 					   check_chan,
135 					   (params->channel_fixed &&
136 					    !radar_detect_width)
137 					   ? CHAN_MODE_SHARED
138 					   : CHAN_MODE_EXCLUSIVE,
139 					   radar_detect_width);
140 
141 	if (err) {
142 		wdev->connect_keys = NULL;
143 		return err;
144 	}
145 
146 	err = rdev_join_ibss(rdev, dev, params);
147 	if (err) {
148 		wdev->connect_keys = NULL;
149 		return err;
150 	}
151 
152 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
153 	wdev->ssid_len = params->ssid_len;
154 
155 	return 0;
156 }
157 
158 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
159 		       struct net_device *dev,
160 		       struct cfg80211_ibss_params *params,
161 		       struct cfg80211_cached_keys *connkeys)
162 {
163 	struct wireless_dev *wdev = dev->ieee80211_ptr;
164 	int err;
165 
166 	ASSERT_RTNL();
167 
168 	wdev_lock(wdev);
169 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
170 	wdev_unlock(wdev);
171 
172 	return err;
173 }
174 
175 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
176 {
177 	struct wireless_dev *wdev = dev->ieee80211_ptr;
178 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
179 	int i;
180 
181 	ASSERT_WDEV_LOCK(wdev);
182 
183 	kfree(wdev->connect_keys);
184 	wdev->connect_keys = NULL;
185 
186 	/*
187 	 * Delete all the keys ... pairwise keys can't really
188 	 * exist any more anyway, but default keys might.
189 	 */
190 	if (rdev->ops->del_key)
191 		for (i = 0; i < 6; i++)
192 			rdev_del_key(rdev, dev, i, false, NULL);
193 
194 	if (wdev->current_bss) {
195 		cfg80211_unhold_bss(wdev->current_bss);
196 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
197 	}
198 
199 	wdev->current_bss = NULL;
200 	wdev->ssid_len = 0;
201 #ifdef CONFIG_CFG80211_WEXT
202 	if (!nowext)
203 		wdev->wext.ibss.ssid_len = 0;
204 #endif
205 }
206 
207 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
208 {
209 	struct wireless_dev *wdev = dev->ieee80211_ptr;
210 
211 	wdev_lock(wdev);
212 	__cfg80211_clear_ibss(dev, nowext);
213 	wdev_unlock(wdev);
214 }
215 
216 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
217 			  struct net_device *dev, bool nowext)
218 {
219 	struct wireless_dev *wdev = dev->ieee80211_ptr;
220 	int err;
221 
222 	ASSERT_WDEV_LOCK(wdev);
223 
224 	if (!wdev->ssid_len)
225 		return -ENOLINK;
226 
227 	err = rdev_leave_ibss(rdev, dev);
228 
229 	if (err)
230 		return err;
231 
232 	__cfg80211_clear_ibss(dev, nowext);
233 
234 	return 0;
235 }
236 
237 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
238 			struct net_device *dev, bool nowext)
239 {
240 	struct wireless_dev *wdev = dev->ieee80211_ptr;
241 	int err;
242 
243 	wdev_lock(wdev);
244 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
245 	wdev_unlock(wdev);
246 
247 	return err;
248 }
249 
250 #ifdef CONFIG_CFG80211_WEXT
251 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
252 			    struct wireless_dev *wdev)
253 {
254 	struct cfg80211_cached_keys *ck = NULL;
255 	enum ieee80211_band band;
256 	int i, err;
257 
258 	ASSERT_WDEV_LOCK(wdev);
259 
260 	if (!wdev->wext.ibss.beacon_interval)
261 		wdev->wext.ibss.beacon_interval = 100;
262 
263 	/* try to find an IBSS channel if none requested ... */
264 	if (!wdev->wext.ibss.chandef.chan) {
265 		struct ieee80211_channel *new_chan = NULL;
266 
267 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
268 			struct ieee80211_supported_band *sband;
269 			struct ieee80211_channel *chan;
270 
271 			sband = rdev->wiphy.bands[band];
272 			if (!sband)
273 				continue;
274 
275 			for (i = 0; i < sband->n_channels; i++) {
276 				chan = &sband->channels[i];
277 				if (chan->flags & IEEE80211_CHAN_NO_IBSS)
278 					continue;
279 				if (chan->flags & IEEE80211_CHAN_DISABLED)
280 					continue;
281 				new_chan = chan;
282 				break;
283 			}
284 
285 			if (new_chan)
286 				break;
287 		}
288 
289 		if (!new_chan)
290 			return -EINVAL;
291 
292 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
293 					NL80211_CHAN_NO_HT);
294 	}
295 
296 	/* don't join -- SSID is not there */
297 	if (!wdev->wext.ibss.ssid_len)
298 		return 0;
299 
300 	if (!netif_running(wdev->netdev))
301 		return 0;
302 
303 	if (wdev->wext.keys) {
304 		wdev->wext.keys->def = wdev->wext.default_key;
305 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
306 	}
307 
308 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
309 
310 	if (wdev->wext.keys) {
311 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
312 		if (!ck)
313 			return -ENOMEM;
314 		for (i = 0; i < 6; i++)
315 			ck->params[i].key = ck->data[i];
316 	}
317 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
318 				   &wdev->wext.ibss, ck);
319 	if (err)
320 		kfree(ck);
321 
322 	return err;
323 }
324 
325 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
326 			       struct iw_request_info *info,
327 			       struct iw_freq *wextfreq, char *extra)
328 {
329 	struct wireless_dev *wdev = dev->ieee80211_ptr;
330 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
331 	struct ieee80211_channel *chan = NULL;
332 	int err, freq;
333 
334 	/* call only for ibss! */
335 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
336 		return -EINVAL;
337 
338 	if (!rdev->ops->join_ibss)
339 		return -EOPNOTSUPP;
340 
341 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
342 	if (freq < 0)
343 		return freq;
344 
345 	if (freq) {
346 		chan = ieee80211_get_channel(wdev->wiphy, freq);
347 		if (!chan)
348 			return -EINVAL;
349 		if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
350 		    chan->flags & IEEE80211_CHAN_DISABLED)
351 			return -EINVAL;
352 	}
353 
354 	if (wdev->wext.ibss.chandef.chan == chan)
355 		return 0;
356 
357 	wdev_lock(wdev);
358 	err = 0;
359 	if (wdev->ssid_len)
360 		err = __cfg80211_leave_ibss(rdev, dev, true);
361 	wdev_unlock(wdev);
362 
363 	if (err)
364 		return err;
365 
366 	if (chan) {
367 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
368 					NL80211_CHAN_NO_HT);
369 		wdev->wext.ibss.channel_fixed = true;
370 	} else {
371 		/* cfg80211_ibss_wext_join will pick one if needed */
372 		wdev->wext.ibss.channel_fixed = false;
373 	}
374 
375 	wdev_lock(wdev);
376 	err = cfg80211_ibss_wext_join(rdev, wdev);
377 	wdev_unlock(wdev);
378 
379 	return err;
380 }
381 
382 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
383 			       struct iw_request_info *info,
384 			       struct iw_freq *freq, char *extra)
385 {
386 	struct wireless_dev *wdev = dev->ieee80211_ptr;
387 	struct ieee80211_channel *chan = NULL;
388 
389 	/* call only for ibss! */
390 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
391 		return -EINVAL;
392 
393 	wdev_lock(wdev);
394 	if (wdev->current_bss)
395 		chan = wdev->current_bss->pub.channel;
396 	else if (wdev->wext.ibss.chandef.chan)
397 		chan = wdev->wext.ibss.chandef.chan;
398 	wdev_unlock(wdev);
399 
400 	if (chan) {
401 		freq->m = chan->center_freq;
402 		freq->e = 6;
403 		return 0;
404 	}
405 
406 	/* no channel if not joining */
407 	return -EINVAL;
408 }
409 
410 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
411 				struct iw_request_info *info,
412 				struct iw_point *data, char *ssid)
413 {
414 	struct wireless_dev *wdev = dev->ieee80211_ptr;
415 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
416 	size_t len = data->length;
417 	int err;
418 
419 	/* call only for ibss! */
420 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
421 		return -EINVAL;
422 
423 	if (!rdev->ops->join_ibss)
424 		return -EOPNOTSUPP;
425 
426 	wdev_lock(wdev);
427 	err = 0;
428 	if (wdev->ssid_len)
429 		err = __cfg80211_leave_ibss(rdev, dev, true);
430 	wdev_unlock(wdev);
431 
432 	if (err)
433 		return err;
434 
435 	/* iwconfig uses nul termination in SSID.. */
436 	if (len > 0 && ssid[len - 1] == '\0')
437 		len--;
438 
439 	wdev->wext.ibss.ssid = wdev->ssid;
440 	memcpy(wdev->wext.ibss.ssid, ssid, len);
441 	wdev->wext.ibss.ssid_len = len;
442 
443 	wdev_lock(wdev);
444 	err = cfg80211_ibss_wext_join(rdev, wdev);
445 	wdev_unlock(wdev);
446 
447 	return err;
448 }
449 
450 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
451 				struct iw_request_info *info,
452 				struct iw_point *data, char *ssid)
453 {
454 	struct wireless_dev *wdev = dev->ieee80211_ptr;
455 
456 	/* call only for ibss! */
457 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
458 		return -EINVAL;
459 
460 	data->flags = 0;
461 
462 	wdev_lock(wdev);
463 	if (wdev->ssid_len) {
464 		data->flags = 1;
465 		data->length = wdev->ssid_len;
466 		memcpy(ssid, wdev->ssid, data->length);
467 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
468 		data->flags = 1;
469 		data->length = wdev->wext.ibss.ssid_len;
470 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
471 	}
472 	wdev_unlock(wdev);
473 
474 	return 0;
475 }
476 
477 int cfg80211_ibss_wext_siwap(struct net_device *dev,
478 			     struct iw_request_info *info,
479 			     struct sockaddr *ap_addr, char *extra)
480 {
481 	struct wireless_dev *wdev = dev->ieee80211_ptr;
482 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
483 	u8 *bssid = ap_addr->sa_data;
484 	int err;
485 
486 	/* call only for ibss! */
487 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
488 		return -EINVAL;
489 
490 	if (!rdev->ops->join_ibss)
491 		return -EOPNOTSUPP;
492 
493 	if (ap_addr->sa_family != ARPHRD_ETHER)
494 		return -EINVAL;
495 
496 	/* automatic mode */
497 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
498 		bssid = NULL;
499 
500 	/* both automatic */
501 	if (!bssid && !wdev->wext.ibss.bssid)
502 		return 0;
503 
504 	/* fixed already - and no change */
505 	if (wdev->wext.ibss.bssid && bssid &&
506 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
507 		return 0;
508 
509 	wdev_lock(wdev);
510 	err = 0;
511 	if (wdev->ssid_len)
512 		err = __cfg80211_leave_ibss(rdev, dev, true);
513 	wdev_unlock(wdev);
514 
515 	if (err)
516 		return err;
517 
518 	if (bssid) {
519 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
520 		wdev->wext.ibss.bssid = wdev->wext.bssid;
521 	} else
522 		wdev->wext.ibss.bssid = NULL;
523 
524 	wdev_lock(wdev);
525 	err = cfg80211_ibss_wext_join(rdev, wdev);
526 	wdev_unlock(wdev);
527 
528 	return err;
529 }
530 
531 int cfg80211_ibss_wext_giwap(struct net_device *dev,
532 			     struct iw_request_info *info,
533 			     struct sockaddr *ap_addr, char *extra)
534 {
535 	struct wireless_dev *wdev = dev->ieee80211_ptr;
536 
537 	/* call only for ibss! */
538 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
539 		return -EINVAL;
540 
541 	ap_addr->sa_family = ARPHRD_ETHER;
542 
543 	wdev_lock(wdev);
544 	if (wdev->current_bss)
545 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
546 	else if (wdev->wext.ibss.bssid)
547 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
548 	else
549 		memset(ap_addr->sa_data, 0, ETH_ALEN);
550 
551 	wdev_unlock(wdev);
552 
553 	return 0;
554 }
555 #endif
556