xref: /openbmc/linux/net/wireless/ibss.c (revision 95298d63)
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 		enum nl80211_band band;
109 		u32 flag;
110 		int j;
111 
112 		band = params->chandef.chan->band;
113 		if (band == NL80211_BAND_5GHZ ||
114 		    band == NL80211_BAND_6GHZ)
115 			flag = IEEE80211_RATE_MANDATORY_A;
116 		else
117 			flag = IEEE80211_RATE_MANDATORY_B;
118 
119 		sband = rdev->wiphy.bands[band];
120 		for (j = 0; j < sband->n_bitrates; j++) {
121 			if (sband->bitrates[j].flags & flag)
122 				params->basic_rates |= BIT(j);
123 		}
124 	}
125 
126 	if (WARN_ON(connkeys && connkeys->def < 0))
127 		return -EINVAL;
128 
129 	if (WARN_ON(wdev->connect_keys))
130 		kzfree(wdev->connect_keys);
131 	wdev->connect_keys = connkeys;
132 
133 	wdev->ibss_fixed = params->channel_fixed;
134 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
135 	wdev->chandef = params->chandef;
136 	if (connkeys) {
137 		params->wep_keys = connkeys->params;
138 		params->wep_tx_key = connkeys->def;
139 	}
140 
141 #ifdef CONFIG_CFG80211_WEXT
142 	wdev->wext.ibss.chandef = params->chandef;
143 #endif
144 	err = rdev_join_ibss(rdev, dev, params);
145 	if (err) {
146 		wdev->connect_keys = NULL;
147 		return err;
148 	}
149 
150 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
151 	wdev->ssid_len = params->ssid_len;
152 
153 	return 0;
154 }
155 
156 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
157 {
158 	struct wireless_dev *wdev = dev->ieee80211_ptr;
159 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
160 	int i;
161 
162 	ASSERT_WDEV_LOCK(wdev);
163 
164 	kzfree(wdev->connect_keys);
165 	wdev->connect_keys = NULL;
166 
167 	rdev_set_qos_map(rdev, dev, NULL);
168 
169 	/*
170 	 * Delete all the keys ... pairwise keys can't really
171 	 * exist any more anyway, but default keys might.
172 	 */
173 	if (rdev->ops->del_key)
174 		for (i = 0; i < 6; i++)
175 			rdev_del_key(rdev, dev, i, false, NULL);
176 
177 	if (wdev->current_bss) {
178 		cfg80211_unhold_bss(wdev->current_bss);
179 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
180 	}
181 
182 	wdev->current_bss = NULL;
183 	wdev->ssid_len = 0;
184 	memset(&wdev->chandef, 0, sizeof(wdev->chandef));
185 #ifdef CONFIG_CFG80211_WEXT
186 	if (!nowext)
187 		wdev->wext.ibss.ssid_len = 0;
188 #endif
189 	cfg80211_sched_dfs_chan_update(rdev);
190 }
191 
192 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
193 {
194 	struct wireless_dev *wdev = dev->ieee80211_ptr;
195 
196 	wdev_lock(wdev);
197 	__cfg80211_clear_ibss(dev, nowext);
198 	wdev_unlock(wdev);
199 }
200 
201 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
202 			  struct net_device *dev, bool nowext)
203 {
204 	struct wireless_dev *wdev = dev->ieee80211_ptr;
205 	int err;
206 
207 	ASSERT_WDEV_LOCK(wdev);
208 
209 	if (!wdev->ssid_len)
210 		return -ENOLINK;
211 
212 	err = rdev_leave_ibss(rdev, dev);
213 
214 	if (err)
215 		return err;
216 
217 	wdev->conn_owner_nlportid = 0;
218 	__cfg80211_clear_ibss(dev, nowext);
219 
220 	return 0;
221 }
222 
223 int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
224 			struct net_device *dev, bool nowext)
225 {
226 	struct wireless_dev *wdev = dev->ieee80211_ptr;
227 	int err;
228 
229 	wdev_lock(wdev);
230 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
231 	wdev_unlock(wdev);
232 
233 	return err;
234 }
235 
236 #ifdef CONFIG_CFG80211_WEXT
237 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
238 			    struct wireless_dev *wdev)
239 {
240 	struct cfg80211_cached_keys *ck = NULL;
241 	enum nl80211_band band;
242 	int i, err;
243 
244 	ASSERT_WDEV_LOCK(wdev);
245 
246 	if (!wdev->wext.ibss.beacon_interval)
247 		wdev->wext.ibss.beacon_interval = 100;
248 
249 	/* try to find an IBSS channel if none requested ... */
250 	if (!wdev->wext.ibss.chandef.chan) {
251 		struct ieee80211_channel *new_chan = NULL;
252 
253 		for (band = 0; band < NUM_NL80211_BANDS; band++) {
254 			struct ieee80211_supported_band *sband;
255 			struct ieee80211_channel *chan;
256 
257 			sband = rdev->wiphy.bands[band];
258 			if (!sband)
259 				continue;
260 
261 			for (i = 0; i < sband->n_channels; i++) {
262 				chan = &sband->channels[i];
263 				if (chan->flags & IEEE80211_CHAN_NO_IR)
264 					continue;
265 				if (chan->flags & IEEE80211_CHAN_DISABLED)
266 					continue;
267 				new_chan = chan;
268 				break;
269 			}
270 
271 			if (new_chan)
272 				break;
273 		}
274 
275 		if (!new_chan)
276 			return -EINVAL;
277 
278 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
279 					NL80211_CHAN_NO_HT);
280 	}
281 
282 	/* don't join -- SSID is not there */
283 	if (!wdev->wext.ibss.ssid_len)
284 		return 0;
285 
286 	if (!netif_running(wdev->netdev))
287 		return 0;
288 
289 	if (wdev->wext.keys)
290 		wdev->wext.keys->def = wdev->wext.default_key;
291 
292 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
293 
294 	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
295 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
296 		if (!ck)
297 			return -ENOMEM;
298 		for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
299 			ck->params[i].key = ck->data[i];
300 	}
301 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
302 				   &wdev->wext.ibss, ck);
303 	if (err)
304 		kfree(ck);
305 
306 	return err;
307 }
308 
309 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
310 			       struct iw_request_info *info,
311 			       struct iw_freq *wextfreq, char *extra)
312 {
313 	struct wireless_dev *wdev = dev->ieee80211_ptr;
314 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
315 	struct ieee80211_channel *chan = NULL;
316 	int err, freq;
317 
318 	/* call only for ibss! */
319 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
320 		return -EINVAL;
321 
322 	if (!rdev->ops->join_ibss)
323 		return -EOPNOTSUPP;
324 
325 	freq = cfg80211_wext_freq(wextfreq);
326 	if (freq < 0)
327 		return freq;
328 
329 	if (freq) {
330 		chan = ieee80211_get_channel(wdev->wiphy, freq);
331 		if (!chan)
332 			return -EINVAL;
333 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
334 		    chan->flags & IEEE80211_CHAN_DISABLED)
335 			return -EINVAL;
336 	}
337 
338 	if (wdev->wext.ibss.chandef.chan == chan)
339 		return 0;
340 
341 	wdev_lock(wdev);
342 	err = 0;
343 	if (wdev->ssid_len)
344 		err = __cfg80211_leave_ibss(rdev, dev, true);
345 	wdev_unlock(wdev);
346 
347 	if (err)
348 		return err;
349 
350 	if (chan) {
351 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
352 					NL80211_CHAN_NO_HT);
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_rdev(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 	memcpy(wdev->ssid, ssid, len);
424 	wdev->wext.ibss.ssid = wdev->ssid;
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_rdev(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 	if (bssid && !is_valid_ether_addr(bssid))
485 		return -EINVAL;
486 
487 	/* both automatic */
488 	if (!bssid && !wdev->wext.ibss.bssid)
489 		return 0;
490 
491 	/* fixed already - and no change */
492 	if (wdev->wext.ibss.bssid && bssid &&
493 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
494 		return 0;
495 
496 	wdev_lock(wdev);
497 	err = 0;
498 	if (wdev->ssid_len)
499 		err = __cfg80211_leave_ibss(rdev, dev, true);
500 	wdev_unlock(wdev);
501 
502 	if (err)
503 		return err;
504 
505 	if (bssid) {
506 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
507 		wdev->wext.ibss.bssid = wdev->wext.bssid;
508 	} else
509 		wdev->wext.ibss.bssid = NULL;
510 
511 	wdev_lock(wdev);
512 	err = cfg80211_ibss_wext_join(rdev, wdev);
513 	wdev_unlock(wdev);
514 
515 	return err;
516 }
517 
518 int cfg80211_ibss_wext_giwap(struct net_device *dev,
519 			     struct iw_request_info *info,
520 			     struct sockaddr *ap_addr, char *extra)
521 {
522 	struct wireless_dev *wdev = dev->ieee80211_ptr;
523 
524 	/* call only for ibss! */
525 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
526 		return -EINVAL;
527 
528 	ap_addr->sa_family = ARPHRD_ETHER;
529 
530 	wdev_lock(wdev);
531 	if (wdev->current_bss)
532 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
533 	else if (wdev->wext.ibss.bssid)
534 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
535 	else
536 		eth_zero_addr(ap_addr->sa_data);
537 
538 	wdev_unlock(wdev);
539 
540 	return 0;
541 }
542 #endif
543