xref: /openbmc/linux/net/wireless/ibss.c (revision 7a010c3c)
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  * Copyright (C) 2020-2021 Intel Corporation
7  */
8 
9 #include <linux/etherdevice.h>
10 #include <linux/if_arp.h>
11 #include <linux/slab.h>
12 #include <linux/export.h>
13 #include <net/cfg80211.h>
14 #include "wext-compat.h"
15 #include "nl80211.h"
16 #include "rdev-ops.h"
17 
18 
19 void __cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
20 			    struct ieee80211_channel *channel)
21 {
22 	struct wireless_dev *wdev = dev->ieee80211_ptr;
23 	struct cfg80211_bss *bss;
24 #ifdef CONFIG_CFG80211_WEXT
25 	union iwreq_data wrqu;
26 #endif
27 
28 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
29 		return;
30 
31 	if (!wdev->ssid_len)
32 		return;
33 
34 	bss = cfg80211_get_bss(wdev->wiphy, channel, bssid, NULL, 0,
35 			       IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY_ANY);
36 
37 	if (WARN_ON(!bss))
38 		return;
39 
40 	if (wdev->current_bss) {
41 		cfg80211_unhold_bss(wdev->current_bss);
42 		cfg80211_put_bss(wdev->wiphy, &wdev->current_bss->pub);
43 	}
44 
45 	cfg80211_hold_bss(bss_from_pub(bss));
46 	wdev->current_bss = bss_from_pub(bss);
47 
48 	if (!(wdev->wiphy->flags & WIPHY_FLAG_HAS_STATIC_WEP))
49 		cfg80211_upload_connect_keys(wdev);
50 
51 	nl80211_send_ibss_bssid(wiphy_to_rdev(wdev->wiphy), dev, bssid,
52 				GFP_KERNEL);
53 #ifdef CONFIG_CFG80211_WEXT
54 	memset(&wrqu, 0, sizeof(wrqu));
55 	memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
56 	wireless_send_event(dev, SIOCGIWAP, &wrqu, NULL);
57 #endif
58 }
59 
60 void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
61 			  struct ieee80211_channel *channel, gfp_t gfp)
62 {
63 	struct wireless_dev *wdev = dev->ieee80211_ptr;
64 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
65 	struct cfg80211_event *ev;
66 	unsigned long flags;
67 
68 	trace_cfg80211_ibss_joined(dev, bssid, channel);
69 
70 	if (WARN_ON(!channel))
71 		return;
72 
73 	ev = kzalloc(sizeof(*ev), gfp);
74 	if (!ev)
75 		return;
76 
77 	ev->type = EVENT_IBSS_JOINED;
78 	memcpy(ev->ij.bssid, bssid, ETH_ALEN);
79 	ev->ij.channel = channel;
80 
81 	spin_lock_irqsave(&wdev->event_lock, flags);
82 	list_add_tail(&ev->list, &wdev->event_list);
83 	spin_unlock_irqrestore(&wdev->event_lock, flags);
84 	queue_work(cfg80211_wq, &rdev->event_work);
85 }
86 EXPORT_SYMBOL(cfg80211_ibss_joined);
87 
88 int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev,
89 			 struct net_device *dev,
90 			 struct cfg80211_ibss_params *params,
91 			 struct cfg80211_cached_keys *connkeys)
92 {
93 	struct wireless_dev *wdev = dev->ieee80211_ptr;
94 	int err;
95 
96 	lockdep_assert_held(&rdev->wiphy.mtx);
97 	ASSERT_WDEV_LOCK(wdev);
98 
99 	if (wdev->ssid_len)
100 		return -EALREADY;
101 
102 	if (!params->basic_rates) {
103 		/*
104 		* If no rates were explicitly configured,
105 		* use the mandatory rate set for 11b or
106 		* 11a for maximum compatibility.
107 		*/
108 		struct ieee80211_supported_band *sband;
109 		enum nl80211_band band;
110 		u32 flag;
111 		int j;
112 
113 		band = params->chandef.chan->band;
114 		if (band == NL80211_BAND_5GHZ ||
115 		    band == NL80211_BAND_6GHZ)
116 			flag = IEEE80211_RATE_MANDATORY_A;
117 		else
118 			flag = IEEE80211_RATE_MANDATORY_B;
119 
120 		sband = rdev->wiphy.bands[band];
121 		for (j = 0; j < sband->n_bitrates; j++) {
122 			if (sband->bitrates[j].flags & flag)
123 				params->basic_rates |= BIT(j);
124 		}
125 	}
126 
127 	if (WARN_ON(connkeys && connkeys->def < 0))
128 		return -EINVAL;
129 
130 	if (WARN_ON(wdev->connect_keys))
131 		kfree_sensitive(wdev->connect_keys);
132 	wdev->connect_keys = connkeys;
133 
134 	wdev->ibss_fixed = params->channel_fixed;
135 	wdev->ibss_dfs_possible = params->userspace_handles_dfs;
136 	wdev->chandef = params->chandef;
137 	if (connkeys) {
138 		params->wep_keys = connkeys->params;
139 		params->wep_tx_key = connkeys->def;
140 	}
141 
142 #ifdef CONFIG_CFG80211_WEXT
143 	wdev->wext.ibss.chandef = params->chandef;
144 #endif
145 	err = rdev_join_ibss(rdev, dev, params);
146 	if (err) {
147 		wdev->connect_keys = NULL;
148 		return err;
149 	}
150 
151 	memcpy(wdev->ssid, params->ssid, params->ssid_len);
152 	wdev->ssid_len = params->ssid_len;
153 
154 	return 0;
155 }
156 
157 static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
158 {
159 	struct wireless_dev *wdev = dev->ieee80211_ptr;
160 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
161 	int i;
162 
163 	ASSERT_WDEV_LOCK(wdev);
164 
165 	kfree_sensitive(wdev->connect_keys);
166 	wdev->connect_keys = NULL;
167 
168 	rdev_set_qos_map(rdev, dev, 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 	memset(&wdev->chandef, 0, sizeof(wdev->chandef));
186 #ifdef CONFIG_CFG80211_WEXT
187 	if (!nowext)
188 		wdev->wext.ibss.ssid_len = 0;
189 #endif
190 	cfg80211_sched_dfs_chan_update(rdev);
191 }
192 
193 void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
194 {
195 	struct wireless_dev *wdev = dev->ieee80211_ptr;
196 
197 	wdev_lock(wdev);
198 	__cfg80211_clear_ibss(dev, nowext);
199 	wdev_unlock(wdev);
200 }
201 
202 int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
203 			  struct net_device *dev, bool nowext)
204 {
205 	struct wireless_dev *wdev = dev->ieee80211_ptr;
206 	int err;
207 
208 	ASSERT_WDEV_LOCK(wdev);
209 
210 	if (!wdev->ssid_len)
211 		return -ENOLINK;
212 
213 	err = rdev_leave_ibss(rdev, dev);
214 
215 	if (err)
216 		return err;
217 
218 	wdev->conn_owner_nlportid = 0;
219 	__cfg80211_clear_ibss(dev, nowext);
220 
221 	return 0;
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 	wdev_lock(wdev);
231 	err = __cfg80211_leave_ibss(rdev, dev, nowext);
232 	wdev_unlock(wdev);
233 
234 	return err;
235 }
236 
237 #ifdef CONFIG_CFG80211_WEXT
238 int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
239 			    struct wireless_dev *wdev)
240 {
241 	struct cfg80211_cached_keys *ck = NULL;
242 	enum nl80211_band band;
243 	int i, err;
244 
245 	ASSERT_WDEV_LOCK(wdev);
246 
247 	if (!wdev->wext.ibss.beacon_interval)
248 		wdev->wext.ibss.beacon_interval = 100;
249 
250 	/* try to find an IBSS channel if none requested ... */
251 	if (!wdev->wext.ibss.chandef.chan) {
252 		struct ieee80211_channel *new_chan = NULL;
253 
254 		for (band = 0; band < NUM_NL80211_BANDS; band++) {
255 			struct ieee80211_supported_band *sband;
256 			struct ieee80211_channel *chan;
257 
258 			sband = rdev->wiphy.bands[band];
259 			if (!sband)
260 				continue;
261 
262 			for (i = 0; i < sband->n_channels; i++) {
263 				chan = &sband->channels[i];
264 				if (chan->flags & IEEE80211_CHAN_NO_IR)
265 					continue;
266 				if (chan->flags & IEEE80211_CHAN_DISABLED)
267 					continue;
268 				new_chan = chan;
269 				break;
270 			}
271 
272 			if (new_chan)
273 				break;
274 		}
275 
276 		if (!new_chan)
277 			return -EINVAL;
278 
279 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
280 					NL80211_CHAN_NO_HT);
281 	}
282 
283 	/* don't join -- SSID is not there */
284 	if (!wdev->wext.ibss.ssid_len)
285 		return 0;
286 
287 	if (!netif_running(wdev->netdev))
288 		return 0;
289 
290 	if (wdev->wext.keys)
291 		wdev->wext.keys->def = wdev->wext.default_key;
292 
293 	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
294 
295 	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
296 		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
297 		if (!ck)
298 			return -ENOMEM;
299 		for (i = 0; i < CFG80211_MAX_WEP_KEYS; i++)
300 			ck->params[i].key = ck->data[i];
301 	}
302 	err = __cfg80211_join_ibss(rdev, wdev->netdev,
303 				   &wdev->wext.ibss, ck);
304 	if (err)
305 		kfree(ck);
306 
307 	return err;
308 }
309 
310 int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
311 			       struct iw_request_info *info,
312 			       struct iw_freq *wextfreq, char *extra)
313 {
314 	struct wireless_dev *wdev = dev->ieee80211_ptr;
315 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
316 	struct ieee80211_channel *chan = NULL;
317 	int err, freq;
318 
319 	/* call only for ibss! */
320 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
321 		return -EINVAL;
322 
323 	if (!rdev->ops->join_ibss)
324 		return -EOPNOTSUPP;
325 
326 	freq = cfg80211_wext_freq(wextfreq);
327 	if (freq < 0)
328 		return freq;
329 
330 	if (freq) {
331 		chan = ieee80211_get_channel(wdev->wiphy, freq);
332 		if (!chan)
333 			return -EINVAL;
334 		if (chan->flags & IEEE80211_CHAN_NO_IR ||
335 		    chan->flags & IEEE80211_CHAN_DISABLED)
336 			return -EINVAL;
337 	}
338 
339 	if (wdev->wext.ibss.chandef.chan == chan)
340 		return 0;
341 
342 	wdev_lock(wdev);
343 	err = 0;
344 	if (wdev->ssid_len)
345 		err = __cfg80211_leave_ibss(rdev, dev, true);
346 	wdev_unlock(wdev);
347 
348 	if (err)
349 		return err;
350 
351 	if (chan) {
352 		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
353 					NL80211_CHAN_NO_HT);
354 		wdev->wext.ibss.channel_fixed = true;
355 	} else {
356 		/* cfg80211_ibss_wext_join will pick one if needed */
357 		wdev->wext.ibss.channel_fixed = false;
358 	}
359 
360 	wdev_lock(wdev);
361 	err = cfg80211_ibss_wext_join(rdev, wdev);
362 	wdev_unlock(wdev);
363 
364 	return err;
365 }
366 
367 int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
368 			       struct iw_request_info *info,
369 			       struct iw_freq *freq, char *extra)
370 {
371 	struct wireless_dev *wdev = dev->ieee80211_ptr;
372 	struct ieee80211_channel *chan = NULL;
373 
374 	/* call only for ibss! */
375 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
376 		return -EINVAL;
377 
378 	wdev_lock(wdev);
379 	if (wdev->current_bss)
380 		chan = wdev->current_bss->pub.channel;
381 	else if (wdev->wext.ibss.chandef.chan)
382 		chan = wdev->wext.ibss.chandef.chan;
383 	wdev_unlock(wdev);
384 
385 	if (chan) {
386 		freq->m = chan->center_freq;
387 		freq->e = 6;
388 		return 0;
389 	}
390 
391 	/* no channel if not joining */
392 	return -EINVAL;
393 }
394 
395 int cfg80211_ibss_wext_siwessid(struct net_device *dev,
396 				struct iw_request_info *info,
397 				struct iw_point *data, char *ssid)
398 {
399 	struct wireless_dev *wdev = dev->ieee80211_ptr;
400 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
401 	size_t len = data->length;
402 	int err;
403 
404 	/* call only for ibss! */
405 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
406 		return -EINVAL;
407 
408 	if (!rdev->ops->join_ibss)
409 		return -EOPNOTSUPP;
410 
411 	wdev_lock(wdev);
412 	err = 0;
413 	if (wdev->ssid_len)
414 		err = __cfg80211_leave_ibss(rdev, dev, true);
415 	wdev_unlock(wdev);
416 
417 	if (err)
418 		return err;
419 
420 	/* iwconfig uses nul termination in SSID.. */
421 	if (len > 0 && ssid[len - 1] == '\0')
422 		len--;
423 
424 	memcpy(wdev->ssid, ssid, len);
425 	wdev->wext.ibss.ssid = wdev->ssid;
426 	wdev->wext.ibss.ssid_len = len;
427 
428 	wdev_lock(wdev);
429 	err = cfg80211_ibss_wext_join(rdev, wdev);
430 	wdev_unlock(wdev);
431 
432 	return err;
433 }
434 
435 int cfg80211_ibss_wext_giwessid(struct net_device *dev,
436 				struct iw_request_info *info,
437 				struct iw_point *data, char *ssid)
438 {
439 	struct wireless_dev *wdev = dev->ieee80211_ptr;
440 
441 	/* call only for ibss! */
442 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
443 		return -EINVAL;
444 
445 	data->flags = 0;
446 
447 	wdev_lock(wdev);
448 	if (wdev->ssid_len) {
449 		data->flags = 1;
450 		data->length = wdev->ssid_len;
451 		memcpy(ssid, wdev->ssid, data->length);
452 	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
453 		data->flags = 1;
454 		data->length = wdev->wext.ibss.ssid_len;
455 		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
456 	}
457 	wdev_unlock(wdev);
458 
459 	return 0;
460 }
461 
462 int cfg80211_ibss_wext_siwap(struct net_device *dev,
463 			     struct iw_request_info *info,
464 			     struct sockaddr *ap_addr, char *extra)
465 {
466 	struct wireless_dev *wdev = dev->ieee80211_ptr;
467 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
468 	u8 *bssid = ap_addr->sa_data;
469 	int err;
470 
471 	/* call only for ibss! */
472 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
473 		return -EINVAL;
474 
475 	if (!rdev->ops->join_ibss)
476 		return -EOPNOTSUPP;
477 
478 	if (ap_addr->sa_family != ARPHRD_ETHER)
479 		return -EINVAL;
480 
481 	/* automatic mode */
482 	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
483 		bssid = NULL;
484 
485 	if (bssid && !is_valid_ether_addr(bssid))
486 		return -EINVAL;
487 
488 	/* both automatic */
489 	if (!bssid && !wdev->wext.ibss.bssid)
490 		return 0;
491 
492 	/* fixed already - and no change */
493 	if (wdev->wext.ibss.bssid && bssid &&
494 	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
495 		return 0;
496 
497 	wdev_lock(wdev);
498 	err = 0;
499 	if (wdev->ssid_len)
500 		err = __cfg80211_leave_ibss(rdev, dev, true);
501 	wdev_unlock(wdev);
502 
503 	if (err)
504 		return err;
505 
506 	if (bssid) {
507 		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
508 		wdev->wext.ibss.bssid = wdev->wext.bssid;
509 	} else
510 		wdev->wext.ibss.bssid = NULL;
511 
512 	wdev_lock(wdev);
513 	err = cfg80211_ibss_wext_join(rdev, wdev);
514 	wdev_unlock(wdev);
515 
516 	return err;
517 }
518 
519 int cfg80211_ibss_wext_giwap(struct net_device *dev,
520 			     struct iw_request_info *info,
521 			     struct sockaddr *ap_addr, char *extra)
522 {
523 	struct wireless_dev *wdev = dev->ieee80211_ptr;
524 
525 	/* call only for ibss! */
526 	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
527 		return -EINVAL;
528 
529 	ap_addr->sa_family = ARPHRD_ETHER;
530 
531 	wdev_lock(wdev);
532 	if (wdev->current_bss)
533 		memcpy(ap_addr->sa_data, wdev->current_bss->pub.bssid, ETH_ALEN);
534 	else if (wdev->wext.ibss.bssid)
535 		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
536 	else
537 		eth_zero_addr(ap_addr->sa_data);
538 
539 	wdev_unlock(wdev);
540 
541 	return 0;
542 }
543 #endif
544