xref: /linux/net/wireless/ibss.c (revision 83bce9c2baa51e439480a713119a73d3c8b61083)
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 			    struct ieee80211_channel *channel)
19 {
20 	struct wireless_dev *wdev = dev->ieee80211_ptr;
21 	struct cfg80211_bss *bss;
22 #ifdef CONFIG_CFG80211_WEXT
23 	union iwreq_data wrqu;
24 #endif
25 
26 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
27 		return;
28 
29 	if (!wdev->ssid_len)
30 		return;
31 
32 	bss = cfg80211_get_bss(wdev->wiphy, channel, bssid, NULL, 0,
33 			       IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY_ANY);
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 	if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
47 		cfg80211_upload_connect_keys(wdev);
48 
49 	nl80211_send_ibss_bssid(wiphy_to_rdev(wdev->wiphy), dev, bssid,
50 				GFP_KERNEL);
51 #ifdef CONFIG_CFG80211_WEXT
52 	memset(&wrqu, 0, sizeof(wrqu));
53 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
54 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
55 #endif
56 }
57 
58 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
59 			  struct ieee80211_channel *channel, gfp_t gfp)
60 {
61 	struct wireless_dev *wdev = dev->ieee80211_ptr;
62 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
63 	struct cfg80211_event *ev;
64 	unsigned long flags;
65 
66 	trace_cfg80211_ibss_joined(dev, bssid, channel);
67 
68 	if (WARN_ON(!channel))
69 		return;
70 
71 	ev = kzalloc(sizeof(*ev), gfp);
72 	if (!ev)
73 		return;
74 
75 	ev->type = EVENT_IBSS_JOINED;
76 	memcpy(ev->ij.bssid, bssid, ETH_ALEN);
77 	ev->ij.channel = channel;
78 
79 	spin_lock_irqsave(&wdev->event_lock, flags);
80 	list_add_tail(&ev->list, &wdev->event_list);
81 	spin_unlock_irqrestore(&wdev->event_lock, flags);
82 	queue_work(cfg80211_wq, &rdev->event_work);
83 }
84 EXPORT_SYMBOL(cfg80211_ibss_joined);
85 
86 static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
87 				struct net_device *dev,
88 				struct cfg80211_ibss_params *params,
89 				struct cfg80211_cached_keys *connkeys)
90 {
91 	struct wireless_dev *wdev = dev->ieee80211_ptr;
92 	int err;
93 
94 	ASSERT_WDEV_LOCK(wdev);
95 
96 	if (wdev->ssid_len)
97 		return -EALREADY;
98 
99 	if (!params->basic_rates) {
100 		/*
101 		* If no rates were explicitly configured,
102 		* use the mandatory rate set for 11b or
103 		* 11a for maximum compatibility.
104 		*/
105 		struct ieee80211_supported_band *sband =
106 			rdev->wiphy.bands[params->chandef.chan->band];
107 		int j;
108 		u32 flag = params->chandef.chan->band == NL80211_BAND_5GHZ ?
109 			IEEE80211_RATE_MANDATORY_A :
110 			IEEE80211_RATE_MANDATORY_B;
111 
112 		for (j = 0; j < sband->n_bitrates; j++) {
113 			if (sband->bitrates[j].flags & flag)
114 				params->basic_rates |= BIT(j);
115 		}
116 	}
117 
118 	if (WARN_ON(connkeys && connkeys->def < 0))
119 		return -EINVAL;
120 
121 	if (WARN_ON(wdev->connect_keys))
122 		kzfree(wdev->connect_keys);
123 	wdev->connect_keys = connkeys;
124 
125 	wdev->ibss_fixed = params->channel_fixed;
126 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
127 	wdev->chandef = params->chandef;
128 #ifdef CONFIG_CFG80211_WEXT
129 	wdev->wext.ibss.chandef = params->chandef;
130 #endif
131 	err = rdev_join_ibss(rdev, dev, params);
132 	if (err) {
133 		wdev->connect_keys = NULL;
134 		return err;
135 	}
136 
137 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
138 	wdev->ssid_len = params->ssid_len;
139 
140 	return 0;
141 }
142 
143 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
144 		       struct net_device *dev,
145 		       struct cfg80211_ibss_params *params,
146 		       struct cfg80211_cached_keys *connkeys)
147 {
148 	struct wireless_dev *wdev = dev->ieee80211_ptr;
149 	int err;
150 
151 	ASSERT_RTNL();
152 
153 	wdev_lock(wdev);
154 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
155 	wdev_unlock(wdev);
156 
157 	return err;
158 }
159 
160 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
161 {
162 	struct wireless_dev *wdev = dev->ieee80211_ptr;
163 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
164 	int i;
165 
166 	ASSERT_WDEV_LOCK(wdev);
167 
168 	kzfree(wdev->connect_keys);
169 	wdev->connect_keys = NULL;
170 
171 	rdev_set_qos_map(rdev, dev, NULL);
172 
173 	/*
174 	 * Delete all the keys ... pairwise keys can't really
175 	 * exist any more anyway, but default keys might.
176 	 */
177 	if (rdev->ops->del_key)
178 		for (i = 0; i < 6; i++)
179 			rdev_del_key(rdev, dev, i, false, NULL);
180 
181 	if (wdev->current_bss) {
182 		cfg80211_unhold_bss(wdev->current_bss);
183 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
184 	}
185 
186 	wdev->current_bss = NULL;
187 	wdev->ssid_len = 0;
188 	memset(&wdev->chandef, 0, sizeof(wdev->chandef));
189 #ifdef CONFIG_CFG80211_WEXT
190 	if (!nowext)
191 		wdev->wext.ibss.ssid_len = 0;
192 #endif
193 }
194 
195 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
196 {
197 	struct wireless_dev *wdev = dev->ieee80211_ptr;
198 
199 	wdev_lock(wdev);
200 	__cfg80211_clear_ibss(dev, nowext);
201 	wdev_unlock(wdev);
202 }
203 
204 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
205 			  struct net_device *dev, bool nowext)
206 {
207 	struct wireless_dev *wdev = dev->ieee80211_ptr;
208 	int err;
209 
210 	ASSERT_WDEV_LOCK(wdev);
211 
212 	if (!wdev->ssid_len)
213 		return -ENOLINK;
214 
215 	err = rdev_leave_ibss(rdev, dev);
216 
217 	if (err)
218 		return err;
219 
220 	__cfg80211_clear_ibss(dev, nowext);
221 
222 	return 0;
223 }
224 
225 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
226 			struct net_device *dev, bool nowext)
227 {
228 	struct wireless_dev *wdev = dev->ieee80211_ptr;
229 	int err;
230 
231 	wdev_lock(wdev);
232 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
233 	wdev_unlock(wdev);
234 
235 	return err;
236 }
237 
238 #ifdef CONFIG_CFG80211_WEXT
239 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
240 			    struct wireless_dev *wdev)
241 {
242 	struct cfg80211_cached_keys *ck = NULL;
243 	enum nl80211_band band;
244 	int i, err;
245 
246 	ASSERT_WDEV_LOCK(wdev);
247 
248 	if (!wdev->wext.ibss.beacon_interval)
249 		wdev->wext.ibss.beacon_interval = 100;
250 
251 	/* try to find an IBSS channel if none requested ... */
252 	if (!wdev->wext.ibss.chandef.chan) {
253 		struct ieee80211_channel *new_chan = NULL;
254 
255 		for (band = 0; band < NUM_NL80211_BANDS; band++) {
256 			struct ieee80211_supported_band *sband;
257 			struct ieee80211_channel *chan;
258 
259 			sband = rdev->wiphy.bands[band];
260 			if (!sband)
261 				continue;
262 
263 			for (i = 0; i < sband->n_channels; i++) {
264 				chan = &sband->channels[i];
265 				if (chan->flags & IEEE80211_CHAN_NO_IR)
266 					continue;
267 				if (chan->flags & IEEE80211_CHAN_DISABLED)
268 					continue;
269 				new_chan = chan;
270 				break;
271 			}
272 
273 			if (new_chan)
274 				break;
275 		}
276 
277 		if (!new_chan)
278 			return -EINVAL;
279 
280 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
281 					NL80211_CHAN_NO_HT);
282 	}
283 
284 	/* don't join -- SSID is not there */
285 	if (!wdev->wext.ibss.ssid_len)
286 		return 0;
287 
288 	if (!netif_running(wdev->netdev))
289 		return 0;
290 
291 	if (wdev->wext.keys)
292 		wdev->wext.keys->def = wdev->wext.default_key;
293 
294 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
295 
296 	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
297 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
298 		if (!ck)
299 			return -ENOMEM;
300 		for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
301 			ck->params[i].key = ck->data[i];
302 	}
303 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
304 				   &wdev->wext.ibss, ck);
305 	if (err)
306 		kfree(ck);
307 
308 	return err;
309 }
310 
311 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
312 			       struct iw_request_info *info,
313 			       struct iw_freq *wextfreq, char *extra)
314 {
315 	struct wireless_dev *wdev = dev->ieee80211_ptr;
316 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
317 	struct ieee80211_channel *chan = NULL;
318 	int err, freq;
319 
320 	/* call only for ibss! */
321 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
322 		return -EINVAL;
323 
324 	if (!rdev->ops->join_ibss)
325 		return -EOPNOTSUPP;
326 
327 	freq = cfg80211_wext_freq(wextfreq);
328 	if (freq < 0)
329 		return freq;
330 
331 	if (freq) {
332 		chan = ieee80211_get_channel(wdev->wiphy, freq);
333 		if (!chan)
334 			return -EINVAL;
335 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
336 		    chan->flags & IEEE80211_CHAN_DISABLED)
337 			return -EINVAL;
338 	}
339 
340 	if (wdev->wext.ibss.chandef.chan == chan)
341 		return 0;
342 
343 	wdev_lock(wdev);
344 	err = 0;
345 	if (wdev->ssid_len)
346 		err = __cfg80211_leave_ibss(rdev, dev, true);
347 	wdev_unlock(wdev);
348 
349 	if (err)
350 		return err;
351 
352 	if (chan) {
353 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
354 					NL80211_CHAN_NO_HT);
355 		wdev->wext.ibss.channel_fixed = true;
356 	} else {
357 		/* cfg80211_ibss_wext_join will pick one if needed */
358 		wdev->wext.ibss.channel_fixed = false;
359 	}
360 
361 	wdev_lock(wdev);
362 	err = cfg80211_ibss_wext_join(rdev, wdev);
363 	wdev_unlock(wdev);
364 
365 	return err;
366 }
367 
368 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
369 			       struct iw_request_info *info,
370 			       struct iw_freq *freq, char *extra)
371 {
372 	struct wireless_dev *wdev = dev->ieee80211_ptr;
373 	struct ieee80211_channel *chan = NULL;
374 
375 	/* call only for ibss! */
376 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
377 		return -EINVAL;
378 
379 	wdev_lock(wdev);
380 	if (wdev->current_bss)
381 		chan = wdev->current_bss->pub.channel;
382 	else if (wdev->wext.ibss.chandef.chan)
383 		chan = wdev->wext.ibss.chandef.chan;
384 	wdev_unlock(wdev);
385 
386 	if (chan) {
387 		freq->m = chan->center_freq;
388 		freq->e = 6;
389 		return 0;
390 	}
391 
392 	/* no channel if not joining */
393 	return -EINVAL;
394 }
395 
396 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
397 				struct iw_request_info *info,
398 				struct iw_point *data, char *ssid)
399 {
400 	struct wireless_dev *wdev = dev->ieee80211_ptr;
401 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
402 	size_t len = data->length;
403 	int err;
404 
405 	/* call only for ibss! */
406 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
407 		return -EINVAL;
408 
409 	if (!rdev->ops->join_ibss)
410 		return -EOPNOTSUPP;
411 
412 	wdev_lock(wdev);
413 	err = 0;
414 	if (wdev->ssid_len)
415 		err = __cfg80211_leave_ibss(rdev, dev, true);
416 	wdev_unlock(wdev);
417 
418 	if (err)
419 		return err;
420 
421 	/* iwconfig uses nul termination in SSID.. */
422 	if (len > 0 && ssid[len - 1] == '\0')
423 		len--;
424 
425 	memcpy(wdev->ssid, ssid, len);
426 	wdev->wext.ibss.ssid = wdev->ssid;
427 	wdev->wext.ibss.ssid_len = len;
428 
429 	wdev_lock(wdev);
430 	err = cfg80211_ibss_wext_join(rdev, wdev);
431 	wdev_unlock(wdev);
432 
433 	return err;
434 }
435 
436 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
437 				struct iw_request_info *info,
438 				struct iw_point *data, char *ssid)
439 {
440 	struct wireless_dev *wdev = dev->ieee80211_ptr;
441 
442 	/* call only for ibss! */
443 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
444 		return -EINVAL;
445 
446 	data->flags = 0;
447 
448 	wdev_lock(wdev);
449 	if (wdev->ssid_len) {
450 		data->flags = 1;
451 		data->length = wdev->ssid_len;
452 		memcpy(ssid, wdev->ssid, data->length);
453 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
454 		data->flags = 1;
455 		data->length = wdev->wext.ibss.ssid_len;
456 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
457 	}
458 	wdev_unlock(wdev);
459 
460 	return 0;
461 }
462 
463 int cfg80211_ibss_wext_siwap(struct net_device *dev,
464 			     struct iw_request_info *info,
465 			     struct sockaddr *ap_addr, char *extra)
466 {
467 	struct wireless_dev *wdev = dev->ieee80211_ptr;
468 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
469 	u8 *bssid = ap_addr->sa_data;
470 	int err;
471 
472 	/* call only for ibss! */
473 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
474 		return -EINVAL;
475 
476 	if (!rdev->ops->join_ibss)
477 		return -EOPNOTSUPP;
478 
479 	if (ap_addr->sa_family != ARPHRD_ETHER)
480 		return -EINVAL;
481 
482 	/* automatic mode */
483 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
484 		bssid = NULL;
485 
486 	if (bssid && !is_valid_ether_addr(bssid))
487 		return -EINVAL;
488 
489 	/* both automatic */
490 	if (!bssid && !wdev->wext.ibss.bssid)
491 		return 0;
492 
493 	/* fixed already - and no change */
494 	if (wdev->wext.ibss.bssid && bssid &&
495 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
496 		return 0;
497 
498 	wdev_lock(wdev);
499 	err = 0;
500 	if (wdev->ssid_len)
501 		err = __cfg80211_leave_ibss(rdev, dev, true);
502 	wdev_unlock(wdev);
503 
504 	if (err)
505 		return err;
506 
507 	if (bssid) {
508 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
509 		wdev->wext.ibss.bssid = wdev->wext.bssid;
510 	} else
511 		wdev->wext.ibss.bssid = NULL;
512 
513 	wdev_lock(wdev);
514 	err = cfg80211_ibss_wext_join(rdev, wdev);
515 	wdev_unlock(wdev);
516 
517 	return err;
518 }
519 
520 int cfg80211_ibss_wext_giwap(struct net_device *dev,
521 			     struct iw_request_info *info,
522 			     struct sockaddr *ap_addr, char *extra)
523 {
524 	struct wireless_dev *wdev = dev->ieee80211_ptr;
525 
526 	/* call only for ibss! */
527 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
528 		return -EINVAL;
529 
530 	ap_addr->sa_family = ARPHRD_ETHER;
531 
532 	wdev_lock(wdev);
533 	if (wdev->current_bss)
534 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
535 	else if (wdev->wext.ibss.bssid)
536 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
537 	else
538 		eth_zero_addr(ap_addr->sa_data);
539 
540 	wdev_unlock(wdev);
541 
542 	return 0;
543 }
544 #endif
545