xref: /openbmc/linux/net/wireless/ibss.c (revision 0c874100)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Some IBSS support code for cfg80211.
4  *
5  * Copyright 2009	Johannes Berg <johannes@sipsolutions.net>
6  */
7 
8 #include <linux/etherdevice.h>
9 #include <linux/if_arp.h>
10 #include <linux/slab.h>
11 #include <linux/export.h>
12 #include <net/cfg80211.h>
13 #include "wext-compat.h"
14 #include "nl80211.h"
15 #include "rdev-ops.h"
16 
17 
18 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
19 			    struct ieee80211_channel *channel)
20 {
21 	struct wireless_dev *wdev = dev->ieee80211_ptr;
22 	struct cfg80211_bss *bss;
23 #ifdef CONFIG_CFG80211_WEXT
24 	union iwreq_data wrqu;
25 #endif
26 
27 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
28 		return;
29 
30 	if (!wdev->ssid_len)
31 		return;
32 
33 	bss = cfg80211_get_bss(wdev->wiphy, channel, bssid, NULL, 0,
34 			       IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY_ANY);
35 
36 	if (WARN_ON(!bss))
37 		return;
38 
39 	if (wdev->current_bss) {
40 		cfg80211_unhold_bss(wdev->current_bss);
41 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
42 	}
43 
44 	cfg80211_hold_bss(bss_from_pub(bss));
45 	wdev->current_bss = bss_from_pub(bss);
46 
47 	if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
48 		cfg80211_upload_connect_keys(wdev);
49 
50 	nl80211_send_ibss_bssid(wiphy_to_rdev(wdev->wiphy), dev, bssid,
51 				GFP_KERNEL);
52 #ifdef CONFIG_CFG80211_WEXT
53 	memset(&wrqu, 0, sizeof(wrqu));
54 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
55 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
56 #endif
57 }
58 
59 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
60 			  struct ieee80211_channel *channel, gfp_t gfp)
61 {
62 	struct wireless_dev *wdev = dev->ieee80211_ptr;
63 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
64 	struct cfg80211_event *ev;
65 	unsigned long flags;
66 
67 	trace_cfg80211_ibss_joined(dev, bssid, channel);
68 
69 	if (WARN_ON(!channel))
70 		return;
71 
72 	ev = kzalloc(sizeof(*ev), gfp);
73 	if (!ev)
74 		return;
75 
76 	ev->type = EVENT_IBSS_JOINED;
77 	memcpy(ev->ij.bssid, bssid, ETH_ALEN);
78 	ev->ij.channel = channel;
79 
80 	spin_lock_irqsave(&wdev->event_lock, flags);
81 	list_add_tail(&ev->list, &wdev->event_list);
82 	spin_unlock_irqrestore(&wdev->event_lock, flags);
83 	queue_work(cfg80211_wq, &rdev->event_work);
84 }
85 EXPORT_SYMBOL(cfg80211_ibss_joined);
86 
87 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
88 			 struct net_device *dev,
89 			 struct cfg80211_ibss_params *params,
90 			 struct cfg80211_cached_keys *connkeys)
91 {
92 	struct wireless_dev *wdev = dev->ieee80211_ptr;
93 	int err;
94 
95 	ASSERT_RTNL();
96 	ASSERT_WDEV_LOCK(wdev);
97 
98 	if (wdev->ssid_len)
99 		return -EALREADY;
100 
101 	if (!params->basic_rates) {
102 		/*
103 		* If no rates were explicitly configured,
104 		* use the mandatory rate set for 11b or
105 		* 11a for maximum compatibility.
106 		*/
107 		struct ieee80211_supported_band *sband =
108 			rdev->wiphy.bands[params->chandef.chan->band];
109 		int j;
110 		u32 flag = params->chandef.chan->band == NL80211_BAND_5GHZ ?
111 			IEEE80211_RATE_MANDATORY_A :
112 			IEEE80211_RATE_MANDATORY_B;
113 
114 		for (j = 0; j < sband->n_bitrates; j++) {
115 			if (sband->bitrates[j].flags & flag)
116 				params->basic_rates |= BIT(j);
117 		}
118 	}
119 
120 	if (WARN_ON(connkeys && connkeys->def < 0))
121 		return -EINVAL;
122 
123 	if (WARN_ON(wdev->connect_keys))
124 		kzfree(wdev->connect_keys);
125 	wdev->connect_keys = connkeys;
126 
127 	wdev->ibss_fixed = params->channel_fixed;
128 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
129 	wdev->chandef = params->chandef;
130 	if (connkeys) {
131 		params->wep_keys = connkeys->params;
132 		params->wep_tx_key = connkeys->def;
133 	}
134 
135 #ifdef CONFIG_CFG80211_WEXT
136 	wdev->wext.ibss.chandef = params->chandef;
137 #endif
138 	err = rdev_join_ibss(rdev, dev, params);
139 	if (err) {
140 		wdev->connect_keys = NULL;
141 		return err;
142 	}
143 
144 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
145 	wdev->ssid_len = params->ssid_len;
146 
147 	return 0;
148 }
149 
150 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
151 {
152 	struct wireless_dev *wdev = dev->ieee80211_ptr;
153 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
154 	int i;
155 
156 	ASSERT_WDEV_LOCK(wdev);
157 
158 	kzfree(wdev->connect_keys);
159 	wdev->connect_keys = NULL;
160 
161 	rdev_set_qos_map(rdev, dev, NULL);
162 
163 	/*
164 	 * Delete all the keys ... pairwise keys can't really
165 	 * exist any more anyway, but default keys might.
166 	 */
167 	if (rdev->ops->del_key)
168 		for (i = 0; i < 6; i++)
169 			rdev_del_key(rdev, dev, i, false, NULL);
170 
171 	if (wdev->current_bss) {
172 		cfg80211_unhold_bss(wdev->current_bss);
173 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
174 	}
175 
176 	wdev->current_bss = NULL;
177 	wdev->ssid_len = 0;
178 	memset(&wdev->chandef, 0, sizeof(wdev->chandef));
179 #ifdef CONFIG_CFG80211_WEXT
180 	if (!nowext)
181 		wdev->wext.ibss.ssid_len = 0;
182 #endif
183 	cfg80211_sched_dfs_chan_update(rdev);
184 }
185 
186 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
187 {
188 	struct wireless_dev *wdev = dev->ieee80211_ptr;
189 
190 	wdev_lock(wdev);
191 	__cfg80211_clear_ibss(dev, nowext);
192 	wdev_unlock(wdev);
193 }
194 
195 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
196 			  struct net_device *dev, bool nowext)
197 {
198 	struct wireless_dev *wdev = dev->ieee80211_ptr;
199 	int err;
200 
201 	ASSERT_WDEV_LOCK(wdev);
202 
203 	if (!wdev->ssid_len)
204 		return -ENOLINK;
205 
206 	err = rdev_leave_ibss(rdev, dev);
207 
208 	if (err)
209 		return err;
210 
211 	wdev->conn_owner_nlportid = 0;
212 	__cfg80211_clear_ibss(dev, nowext);
213 
214 	return 0;
215 }
216 
217 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
218 			struct net_device *dev, bool nowext)
219 {
220 	struct wireless_dev *wdev = dev->ieee80211_ptr;
221 	int err;
222 
223 	wdev_lock(wdev);
224 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
225 	wdev_unlock(wdev);
226 
227 	return err;
228 }
229 
230 #ifdef CONFIG_CFG80211_WEXT
231 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
232 			    struct wireless_dev *wdev)
233 {
234 	struct cfg80211_cached_keys *ck = NULL;
235 	enum nl80211_band band;
236 	int i, err;
237 
238 	ASSERT_WDEV_LOCK(wdev);
239 
240 	if (!wdev->wext.ibss.beacon_interval)
241 		wdev->wext.ibss.beacon_interval = 100;
242 
243 	/* try to find an IBSS channel if none requested ... */
244 	if (!wdev->wext.ibss.chandef.chan) {
245 		struct ieee80211_channel *new_chan = NULL;
246 
247 		for (band = 0; band < NUM_NL80211_BANDS; band++) {
248 			struct ieee80211_supported_band *sband;
249 			struct ieee80211_channel *chan;
250 
251 			sband = rdev->wiphy.bands[band];
252 			if (!sband)
253 				continue;
254 
255 			for (i = 0; i < sband->n_channels; i++) {
256 				chan = &sband->channels[i];
257 				if (chan->flags & IEEE80211_CHAN_NO_IR)
258 					continue;
259 				if (chan->flags & IEEE80211_CHAN_DISABLED)
260 					continue;
261 				new_chan = chan;
262 				break;
263 			}
264 
265 			if (new_chan)
266 				break;
267 		}
268 
269 		if (!new_chan)
270 			return -EINVAL;
271 
272 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
273 					NL80211_CHAN_NO_HT);
274 	}
275 
276 	/* don't join -- SSID is not there */
277 	if (!wdev->wext.ibss.ssid_len)
278 		return 0;
279 
280 	if (!netif_running(wdev->netdev))
281 		return 0;
282 
283 	if (wdev->wext.keys)
284 		wdev->wext.keys->def = wdev->wext.default_key;
285 
286 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
287 
288 	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
289 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
290 		if (!ck)
291 			return -ENOMEM;
292 		for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
293 			ck->params[i].key = ck->data[i];
294 	}
295 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
296 				   &wdev->wext.ibss, ck);
297 	if (err)
298 		kfree(ck);
299 
300 	return err;
301 }
302 
303 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
304 			       struct iw_request_info *info,
305 			       struct iw_freq *wextfreq, char *extra)
306 {
307 	struct wireless_dev *wdev = dev->ieee80211_ptr;
308 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
309 	struct ieee80211_channel *chan = NULL;
310 	int err, freq;
311 
312 	/* call only for ibss! */
313 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
314 		return -EINVAL;
315 
316 	if (!rdev->ops->join_ibss)
317 		return -EOPNOTSUPP;
318 
319 	freq = cfg80211_wext_freq(wextfreq);
320 	if (freq < 0)
321 		return freq;
322 
323 	if (freq) {
324 		chan = ieee80211_get_channel(wdev->wiphy, freq);
325 		if (!chan)
326 			return -EINVAL;
327 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
328 		    chan->flags & IEEE80211_CHAN_DISABLED)
329 			return -EINVAL;
330 	}
331 
332 	if (wdev->wext.ibss.chandef.chan == chan)
333 		return 0;
334 
335 	wdev_lock(wdev);
336 	err = 0;
337 	if (wdev->ssid_len)
338 		err = __cfg80211_leave_ibss(rdev, dev, true);
339 	wdev_unlock(wdev);
340 
341 	if (err)
342 		return err;
343 
344 	if (chan) {
345 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
346 					NL80211_CHAN_NO_HT);
347 		wdev->wext.ibss.channel_fixed = true;
348 	} else {
349 		/* cfg80211_ibss_wext_join will pick one if needed */
350 		wdev->wext.ibss.channel_fixed = false;
351 	}
352 
353 	wdev_lock(wdev);
354 	err = cfg80211_ibss_wext_join(rdev, wdev);
355 	wdev_unlock(wdev);
356 
357 	return err;
358 }
359 
360 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
361 			       struct iw_request_info *info,
362 			       struct iw_freq *freq, char *extra)
363 {
364 	struct wireless_dev *wdev = dev->ieee80211_ptr;
365 	struct ieee80211_channel *chan = NULL;
366 
367 	/* call only for ibss! */
368 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
369 		return -EINVAL;
370 
371 	wdev_lock(wdev);
372 	if (wdev->current_bss)
373 		chan = wdev->current_bss->pub.channel;
374 	else if (wdev->wext.ibss.chandef.chan)
375 		chan = wdev->wext.ibss.chandef.chan;
376 	wdev_unlock(wdev);
377 
378 	if (chan) {
379 		freq->m = chan->center_freq;
380 		freq->e = 6;
381 		return 0;
382 	}
383 
384 	/* no channel if not joining */
385 	return -EINVAL;
386 }
387 
388 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
389 				struct iw_request_info *info,
390 				struct iw_point *data, char *ssid)
391 {
392 	struct wireless_dev *wdev = dev->ieee80211_ptr;
393 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
394 	size_t len = data->length;
395 	int err;
396 
397 	/* call only for ibss! */
398 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
399 		return -EINVAL;
400 
401 	if (!rdev->ops->join_ibss)
402 		return -EOPNOTSUPP;
403 
404 	wdev_lock(wdev);
405 	err = 0;
406 	if (wdev->ssid_len)
407 		err = __cfg80211_leave_ibss(rdev, dev, true);
408 	wdev_unlock(wdev);
409 
410 	if (err)
411 		return err;
412 
413 	/* iwconfig uses nul termination in SSID.. */
414 	if (len > 0 && ssid[len - 1] == '\0')
415 		len--;
416 
417 	memcpy(wdev->ssid, ssid, len);
418 	wdev->wext.ibss.ssid = wdev->ssid;
419 	wdev->wext.ibss.ssid_len = len;
420 
421 	wdev_lock(wdev);
422 	err = cfg80211_ibss_wext_join(rdev, wdev);
423 	wdev_unlock(wdev);
424 
425 	return err;
426 }
427 
428 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
429 				struct iw_request_info *info,
430 				struct iw_point *data, char *ssid)
431 {
432 	struct wireless_dev *wdev = dev->ieee80211_ptr;
433 
434 	/* call only for ibss! */
435 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
436 		return -EINVAL;
437 
438 	data->flags = 0;
439 
440 	wdev_lock(wdev);
441 	if (wdev->ssid_len) {
442 		data->flags = 1;
443 		data->length = wdev->ssid_len;
444 		memcpy(ssid, wdev->ssid, data->length);
445 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
446 		data->flags = 1;
447 		data->length = wdev->wext.ibss.ssid_len;
448 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
449 	}
450 	wdev_unlock(wdev);
451 
452 	return 0;
453 }
454 
455 int cfg80211_ibss_wext_siwap(struct net_device *dev,
456 			     struct iw_request_info *info,
457 			     struct sockaddr *ap_addr, char *extra)
458 {
459 	struct wireless_dev *wdev = dev->ieee80211_ptr;
460 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
461 	u8 *bssid = ap_addr->sa_data;
462 	int err;
463 
464 	/* call only for ibss! */
465 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
466 		return -EINVAL;
467 
468 	if (!rdev->ops->join_ibss)
469 		return -EOPNOTSUPP;
470 
471 	if (ap_addr->sa_family != ARPHRD_ETHER)
472 		return -EINVAL;
473 
474 	/* automatic mode */
475 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
476 		bssid = NULL;
477 
478 	if (bssid && !is_valid_ether_addr(bssid))
479 		return -EINVAL;
480 
481 	/* both automatic */
482 	if (!bssid && !wdev->wext.ibss.bssid)
483 		return 0;
484 
485 	/* fixed already - and no change */
486 	if (wdev->wext.ibss.bssid && bssid &&
487 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
488 		return 0;
489 
490 	wdev_lock(wdev);
491 	err = 0;
492 	if (wdev->ssid_len)
493 		err = __cfg80211_leave_ibss(rdev, dev, true);
494 	wdev_unlock(wdev);
495 
496 	if (err)
497 		return err;
498 
499 	if (bssid) {
500 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
501 		wdev->wext.ibss.bssid = wdev->wext.bssid;
502 	} else
503 		wdev->wext.ibss.bssid = NULL;
504 
505 	wdev_lock(wdev);
506 	err = cfg80211_ibss_wext_join(rdev, wdev);
507 	wdev_unlock(wdev);
508 
509 	return err;
510 }
511 
512 int cfg80211_ibss_wext_giwap(struct net_device *dev,
513 			     struct iw_request_info *info,
514 			     struct sockaddr *ap_addr, char *extra)
515 {
516 	struct wireless_dev *wdev = dev->ieee80211_ptr;
517 
518 	/* call only for ibss! */
519 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
520 		return -EINVAL;
521 
522 	ap_addr->sa_family = ARPHRD_ETHER;
523 
524 	wdev_lock(wdev);
525 	if (wdev->current_bss)
526 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
527 	else if (wdev->wext.ibss.bssid)
528 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
529 	else
530 		eth_zero_addr(ap_addr->sa_data);
531 
532 	wdev_unlock(wdev);
533 
534 	return 0;
535 }
536 #endif
537