xref: /openbmc/linux/net/wireless/ibss.c (revision b34e08d5)
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 			       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,
58 			  struct ieee80211_channel *channel, gfp_t gfp)
59 {
60 	struct wireless_dev *wdev = dev->ieee80211_ptr;
61 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
62 	struct cfg80211_event *ev;
63 	unsigned long flags;
64 
65 	trace_cfg80211_ibss_joined(dev, bssid, channel);
66 
67 	if (WARN_ON(!channel))
68 		return;
69 
70 	ev = kzalloc(sizeof(*ev), gfp);
71 	if (!ev)
72 		return;
73 
74 	ev->type = EVENT_IBSS_JOINED;
75 	memcpy(ev->ij.bssid, bssid, ETH_ALEN);
76 	ev->ij.channel = channel;
77 
78 	spin_lock_irqsave(&wdev->event_lock, flags);
79 	list_add_tail(&ev->list, &wdev->event_list);
80 	spin_unlock_irqrestore(&wdev->event_lock, flags);
81 	queue_work(cfg80211_wq, &rdev->event_work);
82 }
83 EXPORT_SYMBOL(cfg80211_ibss_joined);
84 
85 static int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
86 				struct net_device *dev,
87 				struct cfg80211_ibss_params *params,
88 				struct cfg80211_cached_keys *connkeys)
89 {
90 	struct wireless_dev *wdev = dev->ieee80211_ptr;
91 	struct ieee80211_channel *check_chan;
92 	u8 radar_detect_width = 0;
93 	int err;
94 
95 	ASSERT_WDEV_LOCK(wdev);
96 
97 	if (wdev->ssid_len)
98 		return -EALREADY;
99 
100 	if (!params->basic_rates) {
101 		/*
102 		* If no rates were explicitly configured,
103 		* use the mandatory rate set for 11b or
104 		* 11a for maximum compatibility.
105 		*/
106 		struct ieee80211_supported_band *sband =
107 			rdev->wiphy.bands[params->chandef.chan->band];
108 		int j;
109 		u32 flag = params->chandef.chan->band == IEEE80211_BAND_5GHZ ?
110 			IEEE80211_RATE_MANDATORY_A :
111 			IEEE80211_RATE_MANDATORY_B;
112 
113 		for (j = 0; j < sband->n_bitrates; j++) {
114 			if (sband->bitrates[j].flags & flag)
115 				params->basic_rates |= BIT(j);
116 		}
117 	}
118 
119 	if (WARN_ON(wdev->connect_keys))
120 		kfree(wdev->connect_keys);
121 	wdev->connect_keys = connkeys;
122 
123 	wdev->ibss_fixed = params->channel_fixed;
124 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
125 	wdev->chandef = params->chandef;
126 #ifdef CONFIG_CFG80211_WEXT
127 	wdev->wext.ibss.chandef = params->chandef;
128 #endif
129 	check_chan = params->chandef.chan;
130 	if (params->userspace_handles_dfs) {
131 		/* Check for radar even if the current channel is not
132 		 * a radar channel - it might decide to change to DFS
133 		 * channel later.
134 		 */
135 		radar_detect_width = BIT(params->chandef.width);
136 	}
137 
138 	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
139 					   check_chan,
140 					   (params->channel_fixed &&
141 					    !radar_detect_width)
142 					   ? CHAN_MODE_SHARED
143 					   : CHAN_MODE_EXCLUSIVE,
144 					   radar_detect_width);
145 
146 	if (err) {
147 		wdev->connect_keys = NULL;
148 		return err;
149 	}
150 
151 	err = rdev_join_ibss(rdev, dev, params);
152 	if (err) {
153 		wdev->connect_keys = NULL;
154 		return err;
155 	}
156 
157 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
158 	wdev->ssid_len = params->ssid_len;
159 
160 	return 0;
161 }
162 
163 int cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
164 		       struct net_device *dev,
165 		       struct cfg80211_ibss_params *params,
166 		       struct cfg80211_cached_keys *connkeys)
167 {
168 	struct wireless_dev *wdev = dev->ieee80211_ptr;
169 	int err;
170 
171 	ASSERT_RTNL();
172 
173 	wdev_lock(wdev);
174 	err = __cfg80211_join_ibss(rdev, dev, params, connkeys);
175 	wdev_unlock(wdev);
176 
177 	return err;
178 }
179 
180 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
181 {
182 	struct wireless_dev *wdev = dev->ieee80211_ptr;
183 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
184 	int i;
185 
186 	ASSERT_WDEV_LOCK(wdev);
187 
188 	kfree(wdev->connect_keys);
189 	wdev->connect_keys = NULL;
190 
191 	rdev_set_qos_map(rdev, dev, NULL);
192 
193 	/*
194 	 * Delete all the keys ... pairwise keys can't really
195 	 * exist any more anyway, but default keys might.
196 	 */
197 	if (rdev->ops->del_key)
198 		for (i = 0; i < 6; i++)
199 			rdev_del_key(rdev, dev, i, false, NULL);
200 
201 	if (wdev->current_bss) {
202 		cfg80211_unhold_bss(wdev->current_bss);
203 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
204 	}
205 
206 	wdev->current_bss = NULL;
207 	wdev->ssid_len = 0;
208 	memset(&wdev->chandef, 0, sizeof(wdev->chandef));
209 #ifdef CONFIG_CFG80211_WEXT
210 	if (!nowext)
211 		wdev->wext.ibss.ssid_len = 0;
212 #endif
213 }
214 
215 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
216 {
217 	struct wireless_dev *wdev = dev->ieee80211_ptr;
218 
219 	wdev_lock(wdev);
220 	__cfg80211_clear_ibss(dev, nowext);
221 	wdev_unlock(wdev);
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 	ASSERT_WDEV_LOCK(wdev);
231 
232 	if (!wdev->ssid_len)
233 		return -ENOLINK;
234 
235 	err = rdev_leave_ibss(rdev, dev);
236 
237 	if (err)
238 		return err;
239 
240 	__cfg80211_clear_ibss(dev, nowext);
241 
242 	return 0;
243 }
244 
245 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
246 			struct net_device *dev, bool nowext)
247 {
248 	struct wireless_dev *wdev = dev->ieee80211_ptr;
249 	int err;
250 
251 	wdev_lock(wdev);
252 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
253 	wdev_unlock(wdev);
254 
255 	return err;
256 }
257 
258 #ifdef CONFIG_CFG80211_WEXT
259 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
260 			    struct wireless_dev *wdev)
261 {
262 	struct cfg80211_cached_keys *ck = NULL;
263 	enum ieee80211_band band;
264 	int i, err;
265 
266 	ASSERT_WDEV_LOCK(wdev);
267 
268 	if (!wdev->wext.ibss.beacon_interval)
269 		wdev->wext.ibss.beacon_interval = 100;
270 
271 	/* try to find an IBSS channel if none requested ... */
272 	if (!wdev->wext.ibss.chandef.chan) {
273 		struct ieee80211_channel *new_chan = NULL;
274 
275 		for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
276 			struct ieee80211_supported_band *sband;
277 			struct ieee80211_channel *chan;
278 
279 			sband = rdev->wiphy.bands[band];
280 			if (!sband)
281 				continue;
282 
283 			for (i = 0; i < sband->n_channels; i++) {
284 				chan = &sband->channels[i];
285 				if (chan->flags & IEEE80211_CHAN_NO_IR)
286 					continue;
287 				if (chan->flags & IEEE80211_CHAN_DISABLED)
288 					continue;
289 				new_chan = chan;
290 				break;
291 			}
292 
293 			if (new_chan)
294 				break;
295 		}
296 
297 		if (!new_chan)
298 			return -EINVAL;
299 
300 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
301 					NL80211_CHAN_NO_HT);
302 	}
303 
304 	/* don't join -- SSID is not there */
305 	if (!wdev->wext.ibss.ssid_len)
306 		return 0;
307 
308 	if (!netif_running(wdev->netdev))
309 		return 0;
310 
311 	if (wdev->wext.keys) {
312 		wdev->wext.keys->def = wdev->wext.default_key;
313 		wdev->wext.keys->defmgmt = wdev->wext.default_mgmt_key;
314 	}
315 
316 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
317 
318 	if (wdev->wext.keys) {
319 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
320 		if (!ck)
321 			return -ENOMEM;
322 		for (i = 0; i < 6; i++)
323 			ck->params[i].key = ck->data[i];
324 	}
325 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
326 				   &wdev->wext.ibss, ck);
327 	if (err)
328 		kfree(ck);
329 
330 	return err;
331 }
332 
333 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
334 			       struct iw_request_info *info,
335 			       struct iw_freq *wextfreq, char *extra)
336 {
337 	struct wireless_dev *wdev = dev->ieee80211_ptr;
338 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
339 	struct ieee80211_channel *chan = NULL;
340 	int err, freq;
341 
342 	/* call only for ibss! */
343 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
344 		return -EINVAL;
345 
346 	if (!rdev->ops->join_ibss)
347 		return -EOPNOTSUPP;
348 
349 	freq = cfg80211_wext_freq(wdev->wiphy, wextfreq);
350 	if (freq < 0)
351 		return freq;
352 
353 	if (freq) {
354 		chan = ieee80211_get_channel(wdev->wiphy, freq);
355 		if (!chan)
356 			return -EINVAL;
357 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
358 		    chan->flags & IEEE80211_CHAN_DISABLED)
359 			return -EINVAL;
360 	}
361 
362 	if (wdev->wext.ibss.chandef.chan == chan)
363 		return 0;
364 
365 	wdev_lock(wdev);
366 	err = 0;
367 	if (wdev->ssid_len)
368 		err = __cfg80211_leave_ibss(rdev, dev, true);
369 	wdev_unlock(wdev);
370 
371 	if (err)
372 		return err;
373 
374 	if (chan) {
375 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
376 					NL80211_CHAN_NO_HT);
377 		wdev->wext.ibss.channel_fixed = true;
378 	} else {
379 		/* cfg80211_ibss_wext_join will pick one if needed */
380 		wdev->wext.ibss.channel_fixed = false;
381 	}
382 
383 	wdev_lock(wdev);
384 	err = cfg80211_ibss_wext_join(rdev, wdev);
385 	wdev_unlock(wdev);
386 
387 	return err;
388 }
389 
390 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
391 			       struct iw_request_info *info,
392 			       struct iw_freq *freq, char *extra)
393 {
394 	struct wireless_dev *wdev = dev->ieee80211_ptr;
395 	struct ieee80211_channel *chan = NULL;
396 
397 	/* call only for ibss! */
398 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
399 		return -EINVAL;
400 
401 	wdev_lock(wdev);
402 	if (wdev->current_bss)
403 		chan = wdev->current_bss->pub.channel;
404 	else if (wdev->wext.ibss.chandef.chan)
405 		chan = wdev->wext.ibss.chandef.chan;
406 	wdev_unlock(wdev);
407 
408 	if (chan) {
409 		freq->m = chan->center_freq;
410 		freq->e = 6;
411 		return 0;
412 	}
413 
414 	/* no channel if not joining */
415 	return -EINVAL;
416 }
417 
418 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
419 				struct iw_request_info *info,
420 				struct iw_point *data, char *ssid)
421 {
422 	struct wireless_dev *wdev = dev->ieee80211_ptr;
423 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
424 	size_t len = data->length;
425 	int err;
426 
427 	/* call only for ibss! */
428 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
429 		return -EINVAL;
430 
431 	if (!rdev->ops->join_ibss)
432 		return -EOPNOTSUPP;
433 
434 	wdev_lock(wdev);
435 	err = 0;
436 	if (wdev->ssid_len)
437 		err = __cfg80211_leave_ibss(rdev, dev, true);
438 	wdev_unlock(wdev);
439 
440 	if (err)
441 		return err;
442 
443 	/* iwconfig uses nul termination in SSID.. */
444 	if (len > 0 && ssid[len - 1] == '\0')
445 		len--;
446 
447 	wdev->wext.ibss.ssid = wdev->ssid;
448 	memcpy(wdev->wext.ibss.ssid, ssid, len);
449 	wdev->wext.ibss.ssid_len = len;
450 
451 	wdev_lock(wdev);
452 	err = cfg80211_ibss_wext_join(rdev, wdev);
453 	wdev_unlock(wdev);
454 
455 	return err;
456 }
457 
458 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
459 				struct iw_request_info *info,
460 				struct iw_point *data, char *ssid)
461 {
462 	struct wireless_dev *wdev = dev->ieee80211_ptr;
463 
464 	/* call only for ibss! */
465 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
466 		return -EINVAL;
467 
468 	data->flags = 0;
469 
470 	wdev_lock(wdev);
471 	if (wdev->ssid_len) {
472 		data->flags = 1;
473 		data->length = wdev->ssid_len;
474 		memcpy(ssid, wdev->ssid, data->length);
475 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
476 		data->flags = 1;
477 		data->length = wdev->wext.ibss.ssid_len;
478 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
479 	}
480 	wdev_unlock(wdev);
481 
482 	return 0;
483 }
484 
485 int cfg80211_ibss_wext_siwap(struct net_device *dev,
486 			     struct iw_request_info *info,
487 			     struct sockaddr *ap_addr, char *extra)
488 {
489 	struct wireless_dev *wdev = dev->ieee80211_ptr;
490 	struct cfg80211_registered_device *rdev = wiphy_to_dev(wdev->wiphy);
491 	u8 *bssid = ap_addr->sa_data;
492 	int err;
493 
494 	/* call only for ibss! */
495 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
496 		return -EINVAL;
497 
498 	if (!rdev->ops->join_ibss)
499 		return -EOPNOTSUPP;
500 
501 	if (ap_addr->sa_family != ARPHRD_ETHER)
502 		return -EINVAL;
503 
504 	/* automatic mode */
505 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
506 		bssid = NULL;
507 
508 	/* both automatic */
509 	if (!bssid && !wdev->wext.ibss.bssid)
510 		return 0;
511 
512 	/* fixed already - and no change */
513 	if (wdev->wext.ibss.bssid && bssid &&
514 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
515 		return 0;
516 
517 	wdev_lock(wdev);
518 	err = 0;
519 	if (wdev->ssid_len)
520 		err = __cfg80211_leave_ibss(rdev, dev, true);
521 	wdev_unlock(wdev);
522 
523 	if (err)
524 		return err;
525 
526 	if (bssid) {
527 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
528 		wdev->wext.ibss.bssid = wdev->wext.bssid;
529 	} else
530 		wdev->wext.ibss.bssid = NULL;
531 
532 	wdev_lock(wdev);
533 	err = cfg80211_ibss_wext_join(rdev, wdev);
534 	wdev_unlock(wdev);
535 
536 	return err;
537 }
538 
539 int cfg80211_ibss_wext_giwap(struct net_device *dev,
540 			     struct iw_request_info *info,
541 			     struct sockaddr *ap_addr, char *extra)
542 {
543 	struct wireless_dev *wdev = dev->ieee80211_ptr;
544 
545 	/* call only for ibss! */
546 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
547 		return -EINVAL;
548 
549 	ap_addr->sa_family = ARPHRD_ETHER;
550 
551 	wdev_lock(wdev);
552 	if (wdev->current_bss)
553 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
554 	else if (wdev->wext.ibss.bssid)
555 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
556 	else
557 		memset(ap_addr->sa_data, 0, ETH_ALEN);
558 
559 	wdev_unlock(wdev);
560 
561 	return 0;
562 }
563 #endif
564