xref: /openbmc/linux/net/wireless/ibss.c (revision 37be287c)
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 	rdev_set_qos_map(rdev, dev, NULL);
187 
188 	/*
189 	 * Delete all the keys ... pairwise keys can't really
190 	 * exist any more anyway, but default keys might.
191 	 */
192 	if (rdev->ops->del_key)
193 		for (i = 0; i < 6; i++)
194 			rdev_del_key(rdev, dev, i, false, NULL);
195 
196 	if (wdev->current_bss) {
197 		cfg80211_unhold_bss(wdev->current_bss);
198 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
199 	}
200 
201 	wdev->current_bss = NULL;
202 	wdev->ssid_len = 0;
203 #ifdef CONFIG_CFG80211_WEXT
204 	if (!nowext)
205 		wdev->wext.ibss.ssid_len = 0;
206 #endif
207 }
208 
209 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
210 {
211 	struct wireless_dev *wdev = dev->ieee80211_ptr;
212 
213 	wdev_lock(wdev);
214 	__cfg80211_clear_ibss(dev, nowext);
215 	wdev_unlock(wdev);
216 }
217 
218 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
219 			  struct net_device *dev, bool nowext)
220 {
221 	struct wireless_dev *wdev = dev->ieee80211_ptr;
222 	int err;
223 
224 	ASSERT_WDEV_LOCK(wdev);
225 
226 	if (!wdev->ssid_len)
227 		return -ENOLINK;
228 
229 	err = rdev_leave_ibss(rdev, dev);
230 
231 	if (err)
232 		return err;
233 
234 	__cfg80211_clear_ibss(dev, nowext);
235 
236 	return 0;
237 }
238 
239 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
240 			struct net_device *dev, bool nowext)
241 {
242 	struct wireless_dev *wdev = dev->ieee80211_ptr;
243 	int err;
244 
245 	wdev_lock(wdev);
246 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
247 	wdev_unlock(wdev);
248 
249 	return err;
250 }
251 
252 #ifdef CONFIG_CFG80211_WEXT
253 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
254 			    struct wireless_dev *wdev)
255 {
256 	struct cfg80211_cached_keys *ck = NULL;
257 	enum ieee80211_band band;
258 	int i, err;
259 
260 	ASSERT_WDEV_LOCK(wdev);
261 
262 	if (!wdev->wext.ibss.beacon_interval)
263 		wdev->wext.ibss.beacon_interval = 100;
264 
265 	/* try to find an IBSS channel if none requested ... */
266 	if (!wdev->wext.ibss.chandef.chan) {
267 		struct ieee80211_channel *new_chan = NULL;
268 
269 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
270 			struct ieee80211_supported_band *sband;
271 			struct ieee80211_channel *chan;
272 
273 			sband = rdev->wiphy.bands[band];
274 			if (!sband)
275 				continue;
276 
277 			for (i = 0; i < sband->n_channels; i++) {
278 				chan = &sband->channels[i];
279 				if (chan->flags & IEEE80211_CHAN_NO_IR)
280 					continue;
281 				if (chan->flags & IEEE80211_CHAN_DISABLED)
282 					continue;
283 				new_chan = chan;
284 				break;
285 			}
286 
287 			if (new_chan)
288 				break;
289 		}
290 
291 		if (!new_chan)
292 			return -EINVAL;
293 
294 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
295 					NL80211_CHAN_NO_HT);
296 	}
297 
298 	/* don't join -- SSID is not there */
299 	if (!wdev->wext.ibss.ssid_len)
300 		return 0;
301 
302 	if (!netif_running(wdev->netdev))
303 		return 0;
304 
305 	if (wdev->wext.keys) {
306 		wdev->wext.keys->def = wdev->wext.default_key;
307 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
308 	}
309 
310 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
311 
312 	if (wdev->wext.keys) {
313 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
314 		if (!ck)
315 			return -ENOMEM;
316 		for (i = 0; i < 6; i++)
317 			ck->params[i].key = ck->data[i];
318 	}
319 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
320 				   &wdev->wext.ibss, ck);
321 	if (err)
322 		kfree(ck);
323 
324 	return err;
325 }
326 
327 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
328 			       struct iw_request_info *info,
329 			       struct iw_freq *wextfreq, char *extra)
330 {
331 	struct wireless_dev *wdev = dev->ieee80211_ptr;
332 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
333 	struct ieee80211_channel *chan = NULL;
334 	int err, freq;
335 
336 	/* call only for ibss! */
337 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
338 		return -EINVAL;
339 
340 	if (!rdev->ops->join_ibss)
341 		return -EOPNOTSUPP;
342 
343 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
344 	if (freq < 0)
345 		return freq;
346 
347 	if (freq) {
348 		chan = ieee80211_get_channel(wdev->wiphy, freq);
349 		if (!chan)
350 			return -EINVAL;
351 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
352 		    chan->flags & IEEE80211_CHAN_DISABLED)
353 			return -EINVAL;
354 	}
355 
356 	if (wdev->wext.ibss.chandef.chan == chan)
357 		return 0;
358 
359 	wdev_lock(wdev);
360 	err = 0;
361 	if (wdev->ssid_len)
362 		err = __cfg80211_leave_ibss(rdev, dev, true);
363 	wdev_unlock(wdev);
364 
365 	if (err)
366 		return err;
367 
368 	if (chan) {
369 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
370 					NL80211_CHAN_NO_HT);
371 		wdev->wext.ibss.channel_fixed = true;
372 	} else {
373 		/* cfg80211_ibss_wext_join will pick one if needed */
374 		wdev->wext.ibss.channel_fixed = false;
375 	}
376 
377 	wdev_lock(wdev);
378 	err = cfg80211_ibss_wext_join(rdev, wdev);
379 	wdev_unlock(wdev);
380 
381 	return err;
382 }
383 
384 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
385 			       struct iw_request_info *info,
386 			       struct iw_freq *freq, char *extra)
387 {
388 	struct wireless_dev *wdev = dev->ieee80211_ptr;
389 	struct ieee80211_channel *chan = NULL;
390 
391 	/* call only for ibss! */
392 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
393 		return -EINVAL;
394 
395 	wdev_lock(wdev);
396 	if (wdev->current_bss)
397 		chan = wdev->current_bss->pub.channel;
398 	else if (wdev->wext.ibss.chandef.chan)
399 		chan = wdev->wext.ibss.chandef.chan;
400 	wdev_unlock(wdev);
401 
402 	if (chan) {
403 		freq->m = chan->center_freq;
404 		freq->e = 6;
405 		return 0;
406 	}
407 
408 	/* no channel if not joining */
409 	return -EINVAL;
410 }
411 
412 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
413 				struct iw_request_info *info,
414 				struct iw_point *data, char *ssid)
415 {
416 	struct wireless_dev *wdev = dev->ieee80211_ptr;
417 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
418 	size_t len = data->length;
419 	int err;
420 
421 	/* call only for ibss! */
422 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
423 		return -EINVAL;
424 
425 	if (!rdev->ops->join_ibss)
426 		return -EOPNOTSUPP;
427 
428 	wdev_lock(wdev);
429 	err = 0;
430 	if (wdev->ssid_len)
431 		err = __cfg80211_leave_ibss(rdev, dev, true);
432 	wdev_unlock(wdev);
433 
434 	if (err)
435 		return err;
436 
437 	/* iwconfig uses nul termination in SSID.. */
438 	if (len > 0 && ssid[len - 1] == '\0')
439 		len--;
440 
441 	wdev->wext.ibss.ssid = wdev->ssid;
442 	memcpy(wdev->wext.ibss.ssid, ssid, len);
443 	wdev->wext.ibss.ssid_len = len;
444 
445 	wdev_lock(wdev);
446 	err = cfg80211_ibss_wext_join(rdev, wdev);
447 	wdev_unlock(wdev);
448 
449 	return err;
450 }
451 
452 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
453 				struct iw_request_info *info,
454 				struct iw_point *data, char *ssid)
455 {
456 	struct wireless_dev *wdev = dev->ieee80211_ptr;
457 
458 	/* call only for ibss! */
459 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
460 		return -EINVAL;
461 
462 	data->flags = 0;
463 
464 	wdev_lock(wdev);
465 	if (wdev->ssid_len) {
466 		data->flags = 1;
467 		data->length = wdev->ssid_len;
468 		memcpy(ssid, wdev->ssid, data->length);
469 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
470 		data->flags = 1;
471 		data->length = wdev->wext.ibss.ssid_len;
472 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
473 	}
474 	wdev_unlock(wdev);
475 
476 	return 0;
477 }
478 
479 int cfg80211_ibss_wext_siwap(struct net_device *dev,
480 			     struct iw_request_info *info,
481 			     struct sockaddr *ap_addr, char *extra)
482 {
483 	struct wireless_dev *wdev = dev->ieee80211_ptr;
484 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
485 	u8 *bssid = ap_addr->sa_data;
486 	int err;
487 
488 	/* call only for ibss! */
489 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
490 		return -EINVAL;
491 
492 	if (!rdev->ops->join_ibss)
493 		return -EOPNOTSUPP;
494 
495 	if (ap_addr->sa_family != ARPHRD_ETHER)
496 		return -EINVAL;
497 
498 	/* automatic mode */
499 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
500 		bssid = NULL;
501 
502 	/* both automatic */
503 	if (!bssid && !wdev->wext.ibss.bssid)
504 		return 0;
505 
506 	/* fixed already - and no change */
507 	if (wdev->wext.ibss.bssid && bssid &&
508 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
509 		return 0;
510 
511 	wdev_lock(wdev);
512 	err = 0;
513 	if (wdev->ssid_len)
514 		err = __cfg80211_leave_ibss(rdev, dev, true);
515 	wdev_unlock(wdev);
516 
517 	if (err)
518 		return err;
519 
520 	if (bssid) {
521 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
522 		wdev->wext.ibss.bssid = wdev->wext.bssid;
523 	} else
524 		wdev->wext.ibss.bssid = NULL;
525 
526 	wdev_lock(wdev);
527 	err = cfg80211_ibss_wext_join(rdev, wdev);
528 	wdev_unlock(wdev);
529 
530 	return err;
531 }
532 
533 int cfg80211_ibss_wext_giwap(struct net_device *dev,
534 			     struct iw_request_info *info,
535 			     struct sockaddr *ap_addr, char *extra)
536 {
537 	struct wireless_dev *wdev = dev->ieee80211_ptr;
538 
539 	/* call only for ibss! */
540 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
541 		return -EINVAL;
542 
543 	ap_addr->sa_family = ARPHRD_ETHER;
544 
545 	wdev_lock(wdev);
546 	if (wdev->current_bss)
547 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
548 	else if (wdev->wext.ibss.bssid)
549 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
550 	else
551 		memset(ap_addr->sa_data, 0, ETH_ALEN);
552 
553 	wdev_unlock(wdev);
554 
555 	return 0;
556 }
557 #endif
558