xref: /openbmc/linux/net/wireless/ibss.c (revision f7777dcc)
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 	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->chandef.chan->band];
101 		int j;
102 		u32 flag = params->chandef.chan->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.chandef = params->chandef;
119 #endif
120 
121 	err = cfg80211_can_use_chan(rdev, wdev, params->chandef.chan,
122 				    params->channel_fixed
123 				    ? CHAN_MODE_SHARED
124 				    : CHAN_MODE_EXCLUSIVE);
125 	if (err) {
126 		wdev->connect_keys = NULL;
127 		return err;
128 	}
129 
130 	err = rdev_join_ibss(rdev, dev, params);
131 	if (err) {
132 		wdev->connect_keys = NULL;
133 		return err;
134 	}
135 
136 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
137 	wdev->ssid_len = params->ssid_len;
138 
139 	return 0;
140 }
141 
142 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
143 		       struct net_device *dev,
144 		       struct cfg80211_ibss_params *params,
145 		       struct cfg80211_cached_keys *connkeys)
146 {
147 	struct wireless_dev *wdev = dev->ieee80211_ptr;
148 	int err;
149 
150 	ASSERT_RTNL();
151 
152 	wdev_lock(wdev);
153 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
154 	wdev_unlock(wdev);
155 
156 	return err;
157 }
158 
159 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
160 {
161 	struct wireless_dev *wdev = dev->ieee80211_ptr;
162 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
163 	int i;
164 
165 	ASSERT_WDEV_LOCK(wdev);
166 
167 	kfree(wdev->connect_keys);
168 	wdev->connect_keys = NULL;
169 
170 	/*
171 	 * Delete all the keys ... pairwise keys can't really
172 	 * exist any more anyway, but default keys might.
173 	 */
174 	if (rdev->ops->del_key)
175 		for (i = 0; i < 6; i++)
176 			rdev_del_key(rdev, dev, i, false, NULL);
177 
178 	if (wdev->current_bss) {
179 		cfg80211_unhold_bss(wdev->current_bss);
180 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
181 	}
182 
183 	wdev->current_bss = NULL;
184 	wdev->ssid_len = 0;
185 #ifdef CONFIG_CFG80211_WEXT
186 	if (!nowext)
187 		wdev->wext.ibss.ssid_len = 0;
188 #endif
189 }
190 
191 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
192 {
193 	struct wireless_dev *wdev = dev->ieee80211_ptr;
194 
195 	wdev_lock(wdev);
196 	__cfg80211_clear_ibss(dev, nowext);
197 	wdev_unlock(wdev);
198 }
199 
200 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
201 			  struct net_device *dev, bool nowext)
202 {
203 	struct wireless_dev *wdev = dev->ieee80211_ptr;
204 	int err;
205 
206 	ASSERT_WDEV_LOCK(wdev);
207 
208 	if (!wdev->ssid_len)
209 		return -ENOLINK;
210 
211 	err = rdev_leave_ibss(rdev, dev);
212 
213 	if (err)
214 		return err;
215 
216 	__cfg80211_clear_ibss(dev, nowext);
217 
218 	return 0;
219 }
220 
221 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
222 			struct net_device *dev, bool nowext)
223 {
224 	struct wireless_dev *wdev = dev->ieee80211_ptr;
225 	int err;
226 
227 	wdev_lock(wdev);
228 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
229 	wdev_unlock(wdev);
230 
231 	return err;
232 }
233 
234 #ifdef CONFIG_CFG80211_WEXT
235 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
236 			    struct wireless_dev *wdev)
237 {
238 	struct cfg80211_cached_keys *ck = NULL;
239 	enum ieee80211_band band;
240 	int i, err;
241 
242 	ASSERT_WDEV_LOCK(wdev);
243 
244 	if (!wdev->wext.ibss.beacon_interval)
245 		wdev->wext.ibss.beacon_interval = 100;
246 
247 	/* try to find an IBSS channel if none requested ... */
248 	if (!wdev->wext.ibss.chandef.chan) {
249 		wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
250 
251 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
252 			struct ieee80211_supported_band *sband;
253 			struct ieee80211_channel *chan;
254 
255 			sband = rdev->wiphy.bands[band];
256 			if (!sband)
257 				continue;
258 
259 			for (i = 0; i < sband->n_channels; i++) {
260 				chan = &sband->channels[i];
261 				if (chan->flags & IEEE80211_CHAN_NO_IBSS)
262 					continue;
263 				if (chan->flags & IEEE80211_CHAN_DISABLED)
264 					continue;
265 				wdev->wext.ibss.chandef.chan = chan;
266 				wdev->wext.ibss.chandef.center_freq1 =
267 					chan->center_freq;
268 				break;
269 			}
270 
271 			if (wdev->wext.ibss.chandef.chan)
272 				break;
273 		}
274 
275 		if (!wdev->wext.ibss.chandef.chan)
276 			return -EINVAL;
277 	}
278 
279 	/* don't join -- SSID is not there */
280 	if (!wdev->wext.ibss.ssid_len)
281 		return 0;
282 
283 	if (!netif_running(wdev->netdev))
284 		return 0;
285 
286 	if (wdev->wext.keys) {
287 		wdev->wext.keys->def = wdev->wext.default_key;
288 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
289 	}
290 
291 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
292 
293 	if (wdev->wext.keys) {
294 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
295 		if (!ck)
296 			return -ENOMEM;
297 		for (i = 0; i < 6; i++)
298 			ck->params[i].key = ck->data[i];
299 	}
300 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
301 				   &wdev->wext.ibss, ck);
302 	if (err)
303 		kfree(ck);
304 
305 	return err;
306 }
307 
308 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
309 			       struct iw_request_info *info,
310 			       struct iw_freq *wextfreq, char *extra)
311 {
312 	struct wireless_dev *wdev = dev->ieee80211_ptr;
313 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
314 	struct ieee80211_channel *chan = NULL;
315 	int err, freq;
316 
317 	/* call only for ibss! */
318 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
319 		return -EINVAL;
320 
321 	if (!rdev->ops->join_ibss)
322 		return -EOPNOTSUPP;
323 
324 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
325 	if (freq < 0)
326 		return freq;
327 
328 	if (freq) {
329 		chan = ieee80211_get_channel(wdev->wiphy, freq);
330 		if (!chan)
331 			return -EINVAL;
332 		if (chan->flags & IEEE80211_CHAN_NO_IBSS ||
333 		    chan->flags & IEEE80211_CHAN_DISABLED)
334 			return -EINVAL;
335 	}
336 
337 	if (wdev->wext.ibss.chandef.chan == chan)
338 		return 0;
339 
340 	wdev_lock(wdev);
341 	err = 0;
342 	if (wdev->ssid_len)
343 		err = __cfg80211_leave_ibss(rdev, dev, true);
344 	wdev_unlock(wdev);
345 
346 	if (err)
347 		return err;
348 
349 	if (chan) {
350 		wdev->wext.ibss.chandef.chan = chan;
351 		wdev->wext.ibss.chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
352 		wdev->wext.ibss.chandef.center_freq1 = freq;
353 		wdev->wext.ibss.channel_fixed = true;
354 	} else {
355 		/* cfg80211_ibss_wext_join will pick one if needed */
356 		wdev->wext.ibss.channel_fixed = false;
357 	}
358 
359 	wdev_lock(wdev);
360 	err = cfg80211_ibss_wext_join(rdev, wdev);
361 	wdev_unlock(wdev);
362 
363 	return err;
364 }
365 
366 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
367 			       struct iw_request_info *info,
368 			       struct iw_freq *freq, char *extra)
369 {
370 	struct wireless_dev *wdev = dev->ieee80211_ptr;
371 	struct ieee80211_channel *chan = NULL;
372 
373 	/* call only for ibss! */
374 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
375 		return -EINVAL;
376 
377 	wdev_lock(wdev);
378 	if (wdev->current_bss)
379 		chan = wdev->current_bss->pub.channel;
380 	else if (wdev->wext.ibss.chandef.chan)
381 		chan = wdev->wext.ibss.chandef.chan;
382 	wdev_unlock(wdev);
383 
384 	if (chan) {
385 		freq->m = chan->center_freq;
386 		freq->e = 6;
387 		return 0;
388 	}
389 
390 	/* no channel if not joining */
391 	return -EINVAL;
392 }
393 
394 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
395 				struct iw_request_info *info,
396 				struct iw_point *data, char *ssid)
397 {
398 	struct wireless_dev *wdev = dev->ieee80211_ptr;
399 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
400 	size_t len = data->length;
401 	int err;
402 
403 	/* call only for ibss! */
404 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
405 		return -EINVAL;
406 
407 	if (!rdev->ops->join_ibss)
408 		return -EOPNOTSUPP;
409 
410 	wdev_lock(wdev);
411 	err = 0;
412 	if (wdev->ssid_len)
413 		err = __cfg80211_leave_ibss(rdev, dev, true);
414 	wdev_unlock(wdev);
415 
416 	if (err)
417 		return err;
418 
419 	/* iwconfig uses nul termination in SSID.. */
420 	if (len > 0 && ssid[len - 1] == '\0')
421 		len--;
422 
423 	wdev->wext.ibss.ssid = wdev->ssid;
424 	memcpy(wdev->wext.ibss.ssid, ssid, len);
425 	wdev->wext.ibss.ssid_len = len;
426 
427 	wdev_lock(wdev);
428 	err = cfg80211_ibss_wext_join(rdev, wdev);
429 	wdev_unlock(wdev);
430 
431 	return err;
432 }
433 
434 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
435 				struct iw_request_info *info,
436 				struct iw_point *data, char *ssid)
437 {
438 	struct wireless_dev *wdev = dev->ieee80211_ptr;
439 
440 	/* call only for ibss! */
441 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
442 		return -EINVAL;
443 
444 	data->flags = 0;
445 
446 	wdev_lock(wdev);
447 	if (wdev->ssid_len) {
448 		data->flags = 1;
449 		data->length = wdev->ssid_len;
450 		memcpy(ssid, wdev->ssid, data->length);
451 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
452 		data->flags = 1;
453 		data->length = wdev->wext.ibss.ssid_len;
454 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
455 	}
456 	wdev_unlock(wdev);
457 
458 	return 0;
459 }
460 
461 int cfg80211_ibss_wext_siwap(struct net_device *dev,
462 			     struct iw_request_info *info,
463 			     struct sockaddr *ap_addr, char *extra)
464 {
465 	struct wireless_dev *wdev = dev->ieee80211_ptr;
466 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
467 	u8 *bssid = ap_addr->sa_data;
468 	int err;
469 
470 	/* call only for ibss! */
471 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
472 		return -EINVAL;
473 
474 	if (!rdev->ops->join_ibss)
475 		return -EOPNOTSUPP;
476 
477 	if (ap_addr->sa_family != ARPHRD_ETHER)
478 		return -EINVAL;
479 
480 	/* automatic mode */
481 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
482 		bssid = NULL;
483 
484 	/* both automatic */
485 	if (!bssid && !wdev->wext.ibss.bssid)
486 		return 0;
487 
488 	/* fixed already - and no change */
489 	if (wdev->wext.ibss.bssid && bssid &&
490 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
491 		return 0;
492 
493 	wdev_lock(wdev);
494 	err = 0;
495 	if (wdev->ssid_len)
496 		err = __cfg80211_leave_ibss(rdev, dev, true);
497 	wdev_unlock(wdev);
498 
499 	if (err)
500 		return err;
501 
502 	if (bssid) {
503 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
504 		wdev->wext.ibss.bssid = wdev->wext.bssid;
505 	} else
506 		wdev->wext.ibss.bssid = NULL;
507 
508 	wdev_lock(wdev);
509 	err = cfg80211_ibss_wext_join(rdev, wdev);
510 	wdev_unlock(wdev);
511 
512 	return err;
513 }
514 
515 int cfg80211_ibss_wext_giwap(struct net_device *dev,
516 			     struct iw_request_info *info,
517 			     struct sockaddr *ap_addr, char *extra)
518 {
519 	struct wireless_dev *wdev = dev->ieee80211_ptr;
520 
521 	/* call only for ibss! */
522 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
523 		return -EINVAL;
524 
525 	ap_addr->sa_family = ARPHRD_ETHER;
526 
527 	wdev_lock(wdev);
528 	if (wdev->current_bss)
529 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
530 	else if (wdev->wext.ibss.bssid)
531 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
532 	else
533 		memset(ap_addr->sa_data, 0, ETH_ALEN);
534 
535 	wdev_unlock(wdev);
536 
537 	return 0;
538 }
539 #endif
540