xref: /kernel/linux/linux-6.6/net/wireless/ibss.c (revision 62306a36) 
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) 2020-2022 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
19void __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->u.ibss.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->u.ibss.current_bss) {
41		cfg80211_unhold_bss(wdev->u.ibss.current_bss);
42		cfg80211_put_bss(wdev->wiphy, &wdev->u.ibss.current_bss->pub);
43	}
44
45	cfg80211_hold_bss(bss_from_pub(bss));
46	wdev->u.ibss.current_bss = bss_from_pub(bss);
47
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
59void 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}
85EXPORT_SYMBOL(cfg80211_ibss_joined);
86
87int __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	lockdep_assert_held(&rdev->wiphy.mtx);
96	ASSERT_WDEV_LOCK(wdev);
97
98	if (wdev->u.ibss.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		kfree_sensitive(wdev->connect_keys);
131	wdev->connect_keys = connkeys;
132
133	wdev->u.ibss.chandef = params->chandef;
134	if (connkeys) {
135		params->wep_keys = connkeys->params;
136		params->wep_tx_key = connkeys->def;
137	}
138
139#ifdef CONFIG_CFG80211_WEXT
140	wdev->wext.ibss.chandef = params->chandef;
141#endif
142	err = rdev_join_ibss(rdev, dev, params);
143	if (err) {
144		wdev->connect_keys = NULL;
145		return err;
146	}
147
148	memcpy(wdev->u.ibss.ssid, params->ssid, params->ssid_len);
149	wdev->u.ibss.ssid_len = params->ssid_len;
150
151	return 0;
152}
153
154static void __cfg80211_clear_ibss(struct net_device *dev, bool nowext)
155{
156	struct wireless_dev *wdev = dev->ieee80211_ptr;
157	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
158	int i;
159
160	ASSERT_WDEV_LOCK(wdev);
161
162	kfree_sensitive(wdev->connect_keys);
163	wdev->connect_keys = NULL;
164
165	rdev_set_qos_map(rdev, dev, NULL);
166
167	/*
168	 * Delete all the keys ... pairwise keys can't really
169	 * exist any more anyway, but default keys might.
170	 */
171	if (rdev->ops->del_key)
172		for (i = 0; i < 6; i++)
173			rdev_del_key(rdev, dev, -1, i, false, NULL);
174
175	if (wdev->u.ibss.current_bss) {
176		cfg80211_unhold_bss(wdev->u.ibss.current_bss);
177		cfg80211_put_bss(wdev->wiphy, &wdev->u.ibss.current_bss->pub);
178	}
179
180	wdev->u.ibss.current_bss = NULL;
181	wdev->u.ibss.ssid_len = 0;
182	memset(&wdev->u.ibss.chandef, 0, sizeof(wdev->u.ibss.chandef));
183#ifdef CONFIG_CFG80211_WEXT
184	if (!nowext)
185		wdev->wext.ibss.ssid_len = 0;
186#endif
187	cfg80211_sched_dfs_chan_update(rdev);
188}
189
190void cfg80211_clear_ibss(struct net_device *dev, bool nowext)
191{
192	struct wireless_dev *wdev = dev->ieee80211_ptr;
193
194	wdev_lock(wdev);
195	__cfg80211_clear_ibss(dev, nowext);
196	wdev_unlock(wdev);
197}
198
199int __cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
200			  struct net_device *dev, bool nowext)
201{
202	struct wireless_dev *wdev = dev->ieee80211_ptr;
203	int err;
204
205	ASSERT_WDEV_LOCK(wdev);
206
207	if (!wdev->u.ibss.ssid_len)
208		return -ENOLINK;
209
210	err = rdev_leave_ibss(rdev, dev);
211
212	if (err)
213		return err;
214
215	wdev->conn_owner_nlportid = 0;
216	__cfg80211_clear_ibss(dev, nowext);
217
218	return 0;
219}
220
221int cfg80211_leave_ibss(struct cfg80211_registered_device *rdev,
222			struct net_device *dev, bool nowext)
223{
224	struct wireless_dev *wdev = dev->ieee80211_ptr;
225	int err;
226
227	wdev_lock(wdev);
228	err = __cfg80211_leave_ibss(rdev, dev, nowext);
229	wdev_unlock(wdev);
230
231	return err;
232}
233
234#ifdef CONFIG_CFG80211_WEXT
235int cfg80211_ibss_wext_join(struct cfg80211_registered_device *rdev,
236			    struct wireless_dev *wdev)
237{
238	struct cfg80211_cached_keys *ck = NULL;
239	enum nl80211_band band;
240	int i, err;
241
242	ASSERT_WDEV_LOCK(wdev);
243
244	if (!wdev->wext.ibss.beacon_interval)
245		wdev->wext.ibss.beacon_interval = 100;
246
247	/* try to find an IBSS channel if none requested ... */
248	if (!wdev->wext.ibss.chandef.chan) {
249		struct ieee80211_channel *new_chan = NULL;
250
251		for (band = 0; band < NUM_NL80211_BANDS; band++) {
252			struct ieee80211_supported_band *sband;
253			struct ieee80211_channel *chan;
254
255			sband = rdev->wiphy.bands[band];
256			if (!sband)
257				continue;
258
259			for (i = 0; i < sband->n_channels; i++) {
260				chan = &sband->channels[i];
261				if (chan->flags & IEEE80211_CHAN_NO_IR)
262					continue;
263				if (chan->flags & IEEE80211_CHAN_DISABLED)
264					continue;
265				new_chan = chan;
266				break;
267			}
268
269			if (new_chan)
270				break;
271		}
272
273		if (!new_chan)
274			return -EINVAL;
275
276		cfg80211_chandef_create(&wdev->wext.ibss.chandef, new_chan,
277					NL80211_CHAN_NO_HT);
278	}
279
280	/* don't join -- SSID is not there */
281	if (!wdev->wext.ibss.ssid_len)
282		return 0;
283
284	if (!netif_running(wdev->netdev))
285		return 0;
286
287	if (wdev->wext.keys)
288		wdev->wext.keys->def = wdev->wext.default_key;
289
290	wdev->wext.ibss.privacy = wdev->wext.default_key != -1;
291
292	if (wdev->wext.keys && wdev->wext.keys->def != -1) {
293		ck = kmemdup(wdev->wext.keys, sizeof(*ck), GFP_KERNEL);
294		if (!ck)
295			return -ENOMEM;
296		for (i = 0; i < 4; i++)
297			ck->params[i].key = ck->data[i];
298	}
299	err = __cfg80211_join_ibss(rdev, wdev->netdev,
300				   &wdev->wext.ibss, ck);
301	if (err)
302		kfree(ck);
303
304	return err;
305}
306
307int cfg80211_ibss_wext_siwfreq(struct net_device *dev,
308			       struct iw_request_info *info,
309			       struct iw_freq *wextfreq, char *extra)
310{
311	struct wireless_dev *wdev = dev->ieee80211_ptr;
312	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
313	struct ieee80211_channel *chan = NULL;
314	int err, freq;
315
316	/* call only for ibss! */
317	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
318		return -EINVAL;
319
320	if (!rdev->ops->join_ibss)
321		return -EOPNOTSUPP;
322
323	freq = cfg80211_wext_freq(wextfreq);
324	if (freq < 0)
325		return freq;
326
327	if (freq) {
328		chan = ieee80211_get_channel(wdev->wiphy, freq);
329		if (!chan)
330			return -EINVAL;
331		if (chan->flags & IEEE80211_CHAN_NO_IR ||
332		    chan->flags & IEEE80211_CHAN_DISABLED)
333			return -EINVAL;
334	}
335
336	if (wdev->wext.ibss.chandef.chan == chan)
337		return 0;
338
339	wdev_lock(wdev);
340	err = 0;
341	if (wdev->u.ibss.ssid_len)
342		err = __cfg80211_leave_ibss(rdev, dev, true);
343	wdev_unlock(wdev);
344
345	if (err)
346		return err;
347
348	if (chan) {
349		cfg80211_chandef_create(&wdev->wext.ibss.chandef, chan,
350					NL80211_CHAN_NO_HT);
351		wdev->wext.ibss.channel_fixed = true;
352	} else {
353		/* cfg80211_ibss_wext_join will pick one if needed */
354		wdev->wext.ibss.channel_fixed = false;
355	}
356
357	wdev_lock(wdev);
358	err = cfg80211_ibss_wext_join(rdev, wdev);
359	wdev_unlock(wdev);
360
361	return err;
362}
363
364int cfg80211_ibss_wext_giwfreq(struct net_device *dev,
365			       struct iw_request_info *info,
366			       struct iw_freq *freq, char *extra)
367{
368	struct wireless_dev *wdev = dev->ieee80211_ptr;
369	struct ieee80211_channel *chan = NULL;
370
371	/* call only for ibss! */
372	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
373		return -EINVAL;
374
375	wdev_lock(wdev);
376	if (wdev->u.ibss.current_bss)
377		chan = wdev->u.ibss.current_bss->pub.channel;
378	else if (wdev->wext.ibss.chandef.chan)
379		chan = wdev->wext.ibss.chandef.chan;
380	wdev_unlock(wdev);
381
382	if (chan) {
383		freq->m = chan->center_freq;
384		freq->e = 6;
385		return 0;
386	}
387
388	/* no channel if not joining */
389	return -EINVAL;
390}
391
392int cfg80211_ibss_wext_siwessid(struct net_device *dev,
393				struct iw_request_info *info,
394				struct iw_point *data, char *ssid)
395{
396	struct wireless_dev *wdev = dev->ieee80211_ptr;
397	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
398	size_t len = data->length;
399	int err;
400
401	/* call only for ibss! */
402	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
403		return -EINVAL;
404
405	if (!rdev->ops->join_ibss)
406		return -EOPNOTSUPP;
407
408	wdev_lock(wdev);
409	err = 0;
410	if (wdev->u.ibss.ssid_len)
411		err = __cfg80211_leave_ibss(rdev, dev, true);
412	wdev_unlock(wdev);
413
414	if (err)
415		return err;
416
417	/* iwconfig uses nul termination in SSID.. */
418	if (len > 0 && ssid[len - 1] == '\0')
419		len--;
420
421	memcpy(wdev->u.ibss.ssid, ssid, len);
422	wdev->wext.ibss.ssid = wdev->u.ibss.ssid;
423	wdev->wext.ibss.ssid_len = len;
424
425	wdev_lock(wdev);
426	err = cfg80211_ibss_wext_join(rdev, wdev);
427	wdev_unlock(wdev);
428
429	return err;
430}
431
432int cfg80211_ibss_wext_giwessid(struct net_device *dev,
433				struct iw_request_info *info,
434				struct iw_point *data, char *ssid)
435{
436	struct wireless_dev *wdev = dev->ieee80211_ptr;
437
438	/* call only for ibss! */
439	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
440		return -EINVAL;
441
442	data->flags = 0;
443
444	wdev_lock(wdev);
445	if (wdev->u.ibss.ssid_len) {
446		data->flags = 1;
447		data->length = wdev->u.ibss.ssid_len;
448		memcpy(ssid, wdev->u.ibss.ssid, data->length);
449	} else if (wdev->wext.ibss.ssid && wdev->wext.ibss.ssid_len) {
450		data->flags = 1;
451		data->length = wdev->wext.ibss.ssid_len;
452		memcpy(ssid, wdev->wext.ibss.ssid, data->length);
453	}
454	wdev_unlock(wdev);
455
456	return 0;
457}
458
459int cfg80211_ibss_wext_siwap(struct net_device *dev,
460			     struct iw_request_info *info,
461			     struct sockaddr *ap_addr, char *extra)
462{
463	struct wireless_dev *wdev = dev->ieee80211_ptr;
464	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
465	u8 *bssid = ap_addr->sa_data;
466	int err;
467
468	/* call only for ibss! */
469	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
470		return -EINVAL;
471
472	if (!rdev->ops->join_ibss)
473		return -EOPNOTSUPP;
474
475	if (ap_addr->sa_family != ARPHRD_ETHER)
476		return -EINVAL;
477
478	/* automatic mode */
479	if (is_zero_ether_addr(bssid) || is_broadcast_ether_addr(bssid))
480		bssid = NULL;
481
482	if (bssid && !is_valid_ether_addr(bssid))
483		return -EINVAL;
484
485	/* both automatic */
486	if (!bssid && !wdev->wext.ibss.bssid)
487		return 0;
488
489	/* fixed already - and no change */
490	if (wdev->wext.ibss.bssid && bssid &&
491	    ether_addr_equal(bssid, wdev->wext.ibss.bssid))
492		return 0;
493
494	wdev_lock(wdev);
495	err = 0;
496	if (wdev->u.ibss.ssid_len)
497		err = __cfg80211_leave_ibss(rdev, dev, true);
498	wdev_unlock(wdev);
499
500	if (err)
501		return err;
502
503	if (bssid) {
504		memcpy(wdev->wext.bssid, bssid, ETH_ALEN);
505		wdev->wext.ibss.bssid = wdev->wext.bssid;
506	} else
507		wdev->wext.ibss.bssid = NULL;
508
509	wdev_lock(wdev);
510	err = cfg80211_ibss_wext_join(rdev, wdev);
511	wdev_unlock(wdev);
512
513	return err;
514}
515
516int cfg80211_ibss_wext_giwap(struct net_device *dev,
517			     struct iw_request_info *info,
518			     struct sockaddr *ap_addr, char *extra)
519{
520	struct wireless_dev *wdev = dev->ieee80211_ptr;
521
522	/* call only for ibss! */
523	if (WARN_ON(wdev->iftype != NL80211_IFTYPE_ADHOC))
524		return -EINVAL;
525
526	ap_addr->sa_family = ARPHRD_ETHER;
527
528	wdev_lock(wdev);
529	if (wdev->u.ibss.current_bss)
530		memcpy(ap_addr->sa_data, wdev->u.ibss.current_bss->pub.bssid,
531		       ETH_ALEN);
532	else if (wdev->wext.ibss.bssid)
533		memcpy(ap_addr->sa_data, wdev->wext.ibss.bssid, ETH_ALEN);
534	else
535		eth_zero_addr(ap_addr->sa_data);
536
537	wdev_unlock(wdev);
538
539	return 0;
540}
541#endif
542