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Merge branch 'core-printk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[mirror_ubuntu-bionic-kernel.git] / net / mac80211 / ibss.c
1 /*
2 * IBSS mode implementation
3 * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
4 * Copyright 2004, Instant802 Networks, Inc.
5 * Copyright 2005, Devicescape Software, Inc.
6 * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
7 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
8 * Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License version 2 as
12 * published by the Free Software Foundation.
13 */
14
15 #include <linux/delay.h>
16 #include <linux/slab.h>
17 #include <linux/if_ether.h>
18 #include <linux/skbuff.h>
19 #include <linux/if_arp.h>
20 #include <linux/etherdevice.h>
21 #include <linux/rtnetlink.h>
22 #include <net/mac80211.h>
23
24 #include "ieee80211_i.h"
25 #include "driver-ops.h"
26 #include "rate.h"
27
28 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
29 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
30
31 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
32 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
33
34 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
35
36
37 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
38 const u8 *bssid, const int beacon_int,
39 struct ieee80211_channel *chan,
40 const u32 basic_rates,
41 const u16 capability, u64 tsf,
42 bool creator)
43 {
44 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
45 struct ieee80211_local *local = sdata->local;
46 int rates, i;
47 struct ieee80211_mgmt *mgmt;
48 u8 *pos;
49 struct ieee80211_supported_band *sband;
50 struct cfg80211_bss *bss;
51 u32 bss_change;
52 u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
53 struct cfg80211_chan_def chandef;
54 struct beacon_data *presp;
55 int frame_len;
56
57 sdata_assert_lock(sdata);
58
59 /* Reset own TSF to allow time synchronization work. */
60 drv_reset_tsf(local, sdata);
61
62 if (!ether_addr_equal(ifibss->bssid, bssid))
63 sta_info_flush(sdata);
64
65 /* if merging, indicate to driver that we leave the old IBSS */
66 if (sdata->vif.bss_conf.ibss_joined) {
67 sdata->vif.bss_conf.ibss_joined = false;
68 sdata->vif.bss_conf.ibss_creator = false;
69 sdata->vif.bss_conf.enable_beacon = false;
70 netif_carrier_off(sdata->dev);
71 ieee80211_bss_info_change_notify(sdata,
72 BSS_CHANGED_IBSS |
73 BSS_CHANGED_BEACON_ENABLED);
74 }
75
76 presp = rcu_dereference_protected(ifibss->presp,
77 lockdep_is_held(&sdata->wdev.mtx));
78 rcu_assign_pointer(ifibss->presp, NULL);
79 if (presp)
80 kfree_rcu(presp, rcu_head);
81
82 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
83
84 chandef = ifibss->chandef;
85 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
86 chandef.width = NL80211_CHAN_WIDTH_20;
87 chandef.center_freq1 = chan->center_freq;
88 }
89
90 ieee80211_vif_release_channel(sdata);
91 if (ieee80211_vif_use_channel(sdata, &chandef,
92 ifibss->fixed_channel ?
93 IEEE80211_CHANCTX_SHARED :
94 IEEE80211_CHANCTX_EXCLUSIVE)) {
95 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
96 return;
97 }
98
99 memcpy(ifibss->bssid, bssid, ETH_ALEN);
100
101 sband = local->hw.wiphy->bands[chan->band];
102
103 /* Build IBSS probe response */
104 frame_len = sizeof(struct ieee80211_hdr_3addr) +
105 12 /* struct ieee80211_mgmt.u.beacon */ +
106 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
107 2 + 8 /* max Supported Rates */ +
108 3 /* max DS params */ +
109 4 /* IBSS params */ +
110 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
111 2 + sizeof(struct ieee80211_ht_cap) +
112 2 + sizeof(struct ieee80211_ht_operation) +
113 ifibss->ie_len;
114 presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
115 if (!presp)
116 return;
117
118 presp->head = (void *)(presp + 1);
119
120 mgmt = (void *) presp->head;
121 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
122 IEEE80211_STYPE_PROBE_RESP);
123 eth_broadcast_addr(mgmt->da);
124 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
125 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
126 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
127 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
128 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
129
130 pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
131
132 *pos++ = WLAN_EID_SSID;
133 *pos++ = ifibss->ssid_len;
134 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
135 pos += ifibss->ssid_len;
136
137 rates = min_t(int, 8, sband->n_bitrates);
138 *pos++ = WLAN_EID_SUPP_RATES;
139 *pos++ = rates;
140 for (i = 0; i < rates; i++) {
141 int rate = sband->bitrates[i].bitrate;
142 u8 basic = 0;
143 if (basic_rates & BIT(i))
144 basic = 0x80;
145 *pos++ = basic | (u8) (rate / 5);
146 }
147
148 if (sband->band == IEEE80211_BAND_2GHZ) {
149 *pos++ = WLAN_EID_DS_PARAMS;
150 *pos++ = 1;
151 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
152 }
153
154 *pos++ = WLAN_EID_IBSS_PARAMS;
155 *pos++ = 2;
156 /* FIX: set ATIM window based on scan results */
157 *pos++ = 0;
158 *pos++ = 0;
159
160 if (sband->n_bitrates > 8) {
161 *pos++ = WLAN_EID_EXT_SUPP_RATES;
162 *pos++ = sband->n_bitrates - 8;
163 for (i = 8; i < sband->n_bitrates; i++) {
164 int rate = sband->bitrates[i].bitrate;
165 u8 basic = 0;
166 if (basic_rates & BIT(i))
167 basic = 0x80;
168 *pos++ = basic | (u8) (rate / 5);
169 }
170 }
171
172 if (ifibss->ie_len) {
173 memcpy(pos, ifibss->ie, ifibss->ie_len);
174 pos += ifibss->ie_len;
175 }
176
177 /* add HT capability and information IEs */
178 if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
179 chandef.width != NL80211_CHAN_WIDTH_5 &&
180 chandef.width != NL80211_CHAN_WIDTH_10 &&
181 sband->ht_cap.ht_supported) {
182 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
183 sband->ht_cap.cap);
184 /*
185 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
186 * field and RIFS Mode are reserved in IBSS mode, therefore
187 * keep them at 0
188 */
189 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
190 &chandef, 0);
191 }
192
193 if (local->hw.queues >= IEEE80211_NUM_ACS) {
194 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
195 *pos++ = 7; /* len */
196 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
197 *pos++ = 0x50;
198 *pos++ = 0xf2;
199 *pos++ = 2; /* WME */
200 *pos++ = 0; /* WME info */
201 *pos++ = 1; /* WME ver */
202 *pos++ = 0; /* U-APSD no in use */
203 }
204
205 presp->head_len = pos - presp->head;
206 if (WARN_ON(presp->head_len > frame_len))
207 return;
208
209 rcu_assign_pointer(ifibss->presp, presp);
210
211 sdata->vif.bss_conf.enable_beacon = true;
212 sdata->vif.bss_conf.beacon_int = beacon_int;
213 sdata->vif.bss_conf.basic_rates = basic_rates;
214 sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
215 memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
216 bss_change = BSS_CHANGED_BEACON_INT;
217 bss_change |= ieee80211_reset_erp_info(sdata);
218 bss_change |= BSS_CHANGED_BSSID;
219 bss_change |= BSS_CHANGED_BEACON;
220 bss_change |= BSS_CHANGED_BEACON_ENABLED;
221 bss_change |= BSS_CHANGED_BASIC_RATES;
222 bss_change |= BSS_CHANGED_HT;
223 bss_change |= BSS_CHANGED_IBSS;
224 bss_change |= BSS_CHANGED_SSID;
225
226 /*
227 * In 5 GHz/802.11a, we can always use short slot time.
228 * (IEEE 802.11-2012 18.3.8.7)
229 *
230 * In 2.4GHz, we must always use long slots in IBSS for compatibility
231 * reasons.
232 * (IEEE 802.11-2012 19.4.5)
233 *
234 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
235 */
236 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
237 bss_change |= BSS_CHANGED_ERP_SLOT;
238
239 sdata->vif.bss_conf.ibss_joined = true;
240 sdata->vif.bss_conf.ibss_creator = creator;
241 ieee80211_bss_info_change_notify(sdata, bss_change);
242
243 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
244
245 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
246 mod_timer(&ifibss->timer,
247 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
248
249 bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
250 mgmt, presp->head_len, 0, GFP_KERNEL);
251 cfg80211_put_bss(local->hw.wiphy, bss);
252 netif_carrier_on(sdata->dev);
253 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
254 }
255
256 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
257 struct ieee80211_bss *bss)
258 {
259 struct cfg80211_bss *cbss =
260 container_of((void *)bss, struct cfg80211_bss, priv);
261 struct ieee80211_supported_band *sband;
262 u32 basic_rates;
263 int i, j;
264 u16 beacon_int = cbss->beacon_interval;
265 const struct cfg80211_bss_ies *ies;
266 u64 tsf;
267
268 sdata_assert_lock(sdata);
269
270 if (beacon_int < 10)
271 beacon_int = 10;
272
273 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
274
275 basic_rates = 0;
276
277 for (i = 0; i < bss->supp_rates_len; i++) {
278 int rate = (bss->supp_rates[i] & 0x7f) * 5;
279 bool is_basic = !!(bss->supp_rates[i] & 0x80);
280
281 for (j = 0; j < sband->n_bitrates; j++) {
282 if (sband->bitrates[j].bitrate == rate) {
283 if (is_basic)
284 basic_rates |= BIT(j);
285 break;
286 }
287 }
288 }
289
290 rcu_read_lock();
291 ies = rcu_dereference(cbss->ies);
292 tsf = ies->tsf;
293 rcu_read_unlock();
294
295 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
296 beacon_int,
297 cbss->channel,
298 basic_rates,
299 cbss->capability,
300 tsf, false);
301 }
302
303 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
304 __acquires(RCU)
305 {
306 struct ieee80211_sub_if_data *sdata = sta->sdata;
307 u8 addr[ETH_ALEN];
308
309 memcpy(addr, sta->sta.addr, ETH_ALEN);
310
311 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
312
313 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
314 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
315 /* authorize the station only if the network is not RSN protected. If
316 * not wait for the userspace to authorize it */
317 if (!sta->sdata->u.ibss.control_port)
318 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
319
320 rate_control_rate_init(sta);
321
322 /* If it fails, maybe we raced another insertion? */
323 if (sta_info_insert_rcu(sta))
324 return sta_info_get(sdata, addr);
325 return sta;
326 }
327
328 static struct sta_info *
329 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
330 const u8 *addr, u32 supp_rates)
331 __acquires(RCU)
332 {
333 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
334 struct ieee80211_local *local = sdata->local;
335 struct sta_info *sta;
336 struct ieee80211_chanctx_conf *chanctx_conf;
337 struct ieee80211_supported_band *sband;
338 int band;
339
340 /*
341 * XXX: Consider removing the least recently used entry and
342 * allow new one to be added.
343 */
344 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
345 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
346 sdata->name, addr);
347 rcu_read_lock();
348 return NULL;
349 }
350
351 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
352 rcu_read_lock();
353 return NULL;
354 }
355
356 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
357 rcu_read_lock();
358 return NULL;
359 }
360
361 rcu_read_lock();
362 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
363 if (WARN_ON_ONCE(!chanctx_conf))
364 return NULL;
365 band = chanctx_conf->def.chan->band;
366 rcu_read_unlock();
367
368 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
369 if (!sta) {
370 rcu_read_lock();
371 return NULL;
372 }
373
374 sta->last_rx = jiffies;
375
376 /* make sure mandatory rates are always added */
377 sband = local->hw.wiphy->bands[band];
378 sta->sta.supp_rates[band] = supp_rates |
379 ieee80211_mandatory_rates(sband);
380
381 return ieee80211_ibss_finish_sta(sta);
382 }
383
384 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
385 struct ieee80211_mgmt *mgmt,
386 size_t len)
387 {
388 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
389
390 if (len < IEEE80211_DEAUTH_FRAME_LEN)
391 return;
392
393 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
394 mgmt->sa, mgmt->da, mgmt->bssid, reason);
395 sta_info_destroy_addr(sdata, mgmt->sa);
396 }
397
398 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
399 struct ieee80211_mgmt *mgmt,
400 size_t len)
401 {
402 u16 auth_alg, auth_transaction;
403
404 sdata_assert_lock(sdata);
405
406 if (len < 24 + 6)
407 return;
408
409 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
410 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
411
412 ibss_dbg(sdata,
413 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
414 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
415
416 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
417 return;
418
419 /*
420 * IEEE 802.11 standard does not require authentication in IBSS
421 * networks and most implementations do not seem to use it.
422 * However, try to reply to authentication attempts if someone
423 * has actually implemented this.
424 */
425 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
426 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
427 }
428
429 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
430 struct ieee80211_mgmt *mgmt, size_t len,
431 struct ieee80211_rx_status *rx_status,
432 struct ieee802_11_elems *elems)
433 {
434 struct ieee80211_local *local = sdata->local;
435 int freq;
436 struct cfg80211_bss *cbss;
437 struct ieee80211_bss *bss;
438 struct sta_info *sta;
439 struct ieee80211_channel *channel;
440 u64 beacon_timestamp, rx_timestamp;
441 u32 supp_rates = 0;
442 enum ieee80211_band band = rx_status->band;
443 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
444 bool rates_updated = false;
445
446 if (elems->ds_params)
447 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
448 band);
449 else
450 freq = rx_status->freq;
451
452 channel = ieee80211_get_channel(local->hw.wiphy, freq);
453
454 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
455 return;
456
457 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
458 ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) {
459
460 rcu_read_lock();
461 sta = sta_info_get(sdata, mgmt->sa);
462
463 if (elems->supp_rates) {
464 supp_rates = ieee80211_sta_get_rates(local, elems,
465 band, NULL);
466 if (sta) {
467 u32 prev_rates;
468
469 prev_rates = sta->sta.supp_rates[band];
470 /* make sure mandatory rates are always added */
471 sta->sta.supp_rates[band] = supp_rates |
472 ieee80211_mandatory_rates(sband);
473
474 if (sta->sta.supp_rates[band] != prev_rates) {
475 ibss_dbg(sdata,
476 "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n",
477 sta->sta.addr, prev_rates,
478 sta->sta.supp_rates[band]);
479 rates_updated = true;
480 }
481 } else {
482 rcu_read_unlock();
483 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
484 mgmt->sa, supp_rates);
485 }
486 }
487
488 if (sta && elems->wmm_info)
489 set_sta_flag(sta, WLAN_STA_WME);
490
491 if (sta && elems->ht_operation && elems->ht_cap_elem &&
492 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
493 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 &&
494 sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) {
495 /* we both use HT */
496 struct ieee80211_ht_cap htcap_ie;
497 struct cfg80211_chan_def chandef;
498
499 ieee80211_ht_oper_to_chandef(channel,
500 elems->ht_operation,
501 &chandef);
502
503 memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie));
504
505 /*
506 * fall back to HT20 if we don't use or use
507 * the other extension channel
508 */
509 if (chandef.center_freq1 !=
510 sdata->u.ibss.chandef.center_freq1)
511 htcap_ie.cap_info &=
512 cpu_to_le16(~IEEE80211_HT_CAP_SUP_WIDTH_20_40);
513
514 rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(
515 sdata, sband, &htcap_ie, sta);
516 }
517
518 if (sta && rates_updated) {
519 drv_sta_rc_update(local, sdata, &sta->sta,
520 IEEE80211_RC_SUPP_RATES_CHANGED);
521 rate_control_rate_init(sta);
522 }
523
524 rcu_read_unlock();
525 }
526
527 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
528 channel);
529 if (!bss)
530 return;
531
532 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
533
534 /* same for beacon and probe response */
535 beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp);
536
537 /* check if we need to merge IBSS */
538
539 /* we use a fixed BSSID */
540 if (sdata->u.ibss.fixed_bssid)
541 goto put_bss;
542
543 /* not an IBSS */
544 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
545 goto put_bss;
546
547 /* different channel */
548 if (sdata->u.ibss.fixed_channel &&
549 sdata->u.ibss.chandef.chan != cbss->channel)
550 goto put_bss;
551
552 /* different SSID */
553 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
554 memcmp(elems->ssid, sdata->u.ibss.ssid,
555 sdata->u.ibss.ssid_len))
556 goto put_bss;
557
558 /* same BSSID */
559 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
560 goto put_bss;
561
562 if (ieee80211_have_rx_timestamp(rx_status)) {
563 /* time when timestamp field was received */
564 rx_timestamp =
565 ieee80211_calculate_rx_timestamp(local, rx_status,
566 len + FCS_LEN, 24);
567 } else {
568 /*
569 * second best option: get current TSF
570 * (will return -1 if not supported)
571 */
572 rx_timestamp = drv_get_tsf(local, sdata);
573 }
574
575 ibss_dbg(sdata,
576 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
577 mgmt->sa, mgmt->bssid,
578 (unsigned long long)rx_timestamp,
579 (unsigned long long)beacon_timestamp,
580 (unsigned long long)(rx_timestamp - beacon_timestamp),
581 jiffies);
582
583 if (beacon_timestamp > rx_timestamp) {
584 ibss_dbg(sdata,
585 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
586 mgmt->bssid);
587 ieee80211_sta_join_ibss(sdata, bss);
588 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
589 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
590 supp_rates);
591 rcu_read_unlock();
592 }
593
594 put_bss:
595 ieee80211_rx_bss_put(local, bss);
596 }
597
598 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
599 const u8 *bssid, const u8 *addr,
600 u32 supp_rates)
601 {
602 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
603 struct ieee80211_local *local = sdata->local;
604 struct sta_info *sta;
605 struct ieee80211_chanctx_conf *chanctx_conf;
606 struct ieee80211_supported_band *sband;
607 int band;
608
609 /*
610 * XXX: Consider removing the least recently used entry and
611 * allow new one to be added.
612 */
613 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
614 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
615 sdata->name, addr);
616 return;
617 }
618
619 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
620 return;
621
622 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
623 return;
624
625 rcu_read_lock();
626 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
627 if (WARN_ON_ONCE(!chanctx_conf)) {
628 rcu_read_unlock();
629 return;
630 }
631 band = chanctx_conf->def.chan->band;
632 rcu_read_unlock();
633
634 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
635 if (!sta)
636 return;
637
638 sta->last_rx = jiffies;
639
640 /* make sure mandatory rates are always added */
641 sband = local->hw.wiphy->bands[band];
642 sta->sta.supp_rates[band] = supp_rates |
643 ieee80211_mandatory_rates(sband);
644
645 spin_lock(&ifibss->incomplete_lock);
646 list_add(&sta->list, &ifibss->incomplete_stations);
647 spin_unlock(&ifibss->incomplete_lock);
648 ieee80211_queue_work(&local->hw, &sdata->work);
649 }
650
651 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
652 {
653 struct ieee80211_local *local = sdata->local;
654 int active = 0;
655 struct sta_info *sta;
656
657 sdata_assert_lock(sdata);
658
659 rcu_read_lock();
660
661 list_for_each_entry_rcu(sta, &local->sta_list, list) {
662 if (sta->sdata == sdata &&
663 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
664 jiffies)) {
665 active++;
666 break;
667 }
668 }
669
670 rcu_read_unlock();
671
672 return active;
673 }
674
675 /*
676 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
677 */
678
679 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
680 {
681 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
682
683 sdata_assert_lock(sdata);
684
685 mod_timer(&ifibss->timer,
686 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
687
688 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
689
690 if (time_before(jiffies, ifibss->last_scan_completed +
691 IEEE80211_IBSS_MERGE_INTERVAL))
692 return;
693
694 if (ieee80211_sta_active_ibss(sdata))
695 return;
696
697 if (ifibss->fixed_channel)
698 return;
699
700 sdata_info(sdata,
701 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
702
703 ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len,
704 NULL);
705 }
706
707 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
708 {
709 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
710 u8 bssid[ETH_ALEN];
711 u16 capability;
712 int i;
713
714 sdata_assert_lock(sdata);
715
716 if (ifibss->fixed_bssid) {
717 memcpy(bssid, ifibss->bssid, ETH_ALEN);
718 } else {
719 /* Generate random, not broadcast, locally administered BSSID. Mix in
720 * own MAC address to make sure that devices that do not have proper
721 * random number generator get different BSSID. */
722 get_random_bytes(bssid, ETH_ALEN);
723 for (i = 0; i < ETH_ALEN; i++)
724 bssid[i] ^= sdata->vif.addr[i];
725 bssid[0] &= ~0x01;
726 bssid[0] |= 0x02;
727 }
728
729 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
730
731 capability = WLAN_CAPABILITY_IBSS;
732
733 if (ifibss->privacy)
734 capability |= WLAN_CAPABILITY_PRIVACY;
735 else
736 sdata->drop_unencrypted = 0;
737
738 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
739 ifibss->chandef.chan, ifibss->basic_rates,
740 capability, 0, true);
741 }
742
743 /*
744 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
745 */
746
747 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
748 {
749 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
750 struct ieee80211_local *local = sdata->local;
751 struct cfg80211_bss *cbss;
752 struct ieee80211_channel *chan = NULL;
753 const u8 *bssid = NULL;
754 int active_ibss;
755 u16 capability;
756
757 sdata_assert_lock(sdata);
758
759 active_ibss = ieee80211_sta_active_ibss(sdata);
760 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
761
762 if (active_ibss)
763 return;
764
765 capability = WLAN_CAPABILITY_IBSS;
766 if (ifibss->privacy)
767 capability |= WLAN_CAPABILITY_PRIVACY;
768 if (ifibss->fixed_bssid)
769 bssid = ifibss->bssid;
770 if (ifibss->fixed_channel)
771 chan = ifibss->chandef.chan;
772 if (!is_zero_ether_addr(ifibss->bssid))
773 bssid = ifibss->bssid;
774 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
775 ifibss->ssid, ifibss->ssid_len,
776 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
777 capability);
778
779 if (cbss) {
780 struct ieee80211_bss *bss;
781
782 bss = (void *)cbss->priv;
783 ibss_dbg(sdata,
784 "sta_find_ibss: selected %pM current %pM\n",
785 cbss->bssid, ifibss->bssid);
786 sdata_info(sdata,
787 "Selected IBSS BSSID %pM based on configured SSID\n",
788 cbss->bssid);
789
790 ieee80211_sta_join_ibss(sdata, bss);
791 ieee80211_rx_bss_put(local, bss);
792 return;
793 }
794
795 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
796
797 /* Selected IBSS not found in current scan results - try to scan */
798 if (time_after(jiffies, ifibss->last_scan_completed +
799 IEEE80211_SCAN_INTERVAL)) {
800 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
801
802 ieee80211_request_ibss_scan(sdata, ifibss->ssid,
803 ifibss->ssid_len, chan);
804 } else {
805 int interval = IEEE80211_SCAN_INTERVAL;
806
807 if (time_after(jiffies, ifibss->ibss_join_req +
808 IEEE80211_IBSS_JOIN_TIMEOUT))
809 ieee80211_sta_create_ibss(sdata);
810
811 mod_timer(&ifibss->timer,
812 round_jiffies(jiffies + interval));
813 }
814 }
815
816 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
817 struct sk_buff *req)
818 {
819 struct ieee80211_mgmt *mgmt = (void *)req->data;
820 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
821 struct ieee80211_local *local = sdata->local;
822 int tx_last_beacon, len = req->len;
823 struct sk_buff *skb;
824 struct beacon_data *presp;
825 u8 *pos, *end;
826
827 sdata_assert_lock(sdata);
828
829 presp = rcu_dereference_protected(ifibss->presp,
830 lockdep_is_held(&sdata->wdev.mtx));
831
832 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
833 len < 24 + 2 || !presp)
834 return;
835
836 tx_last_beacon = drv_tx_last_beacon(local);
837
838 ibss_dbg(sdata,
839 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
840 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
841
842 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
843 return;
844
845 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
846 !is_broadcast_ether_addr(mgmt->bssid))
847 return;
848
849 end = ((u8 *) mgmt) + len;
850 pos = mgmt->u.probe_req.variable;
851 if (pos[0] != WLAN_EID_SSID ||
852 pos + 2 + pos[1] > end) {
853 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
854 mgmt->sa);
855 return;
856 }
857 if (pos[1] != 0 &&
858 (pos[1] != ifibss->ssid_len ||
859 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
860 /* Ignore ProbeReq for foreign SSID */
861 return;
862 }
863
864 /* Reply with ProbeResp */
865 skb = dev_alloc_skb(local->tx_headroom + presp->head_len);
866 if (!skb)
867 return;
868
869 skb_reserve(skb, local->tx_headroom);
870 memcpy(skb_put(skb, presp->head_len), presp->head, presp->head_len);
871
872 memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN);
873 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa);
874 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
875 ieee80211_tx_skb(sdata, skb);
876 }
877
878 static
879 void ieee80211_rx_mgmt_probe_beacon(struct ieee80211_sub_if_data *sdata,
880 struct ieee80211_mgmt *mgmt, size_t len,
881 struct ieee80211_rx_status *rx_status)
882 {
883 size_t baselen;
884 struct ieee802_11_elems elems;
885
886 BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) !=
887 offsetof(typeof(mgmt->u.beacon), variable));
888
889 /*
890 * either beacon or probe_resp but the variable field is at the
891 * same offset
892 */
893 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
894 if (baselen > len)
895 return;
896
897 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
898 false, &elems);
899
900 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems);
901 }
902
903 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
904 struct sk_buff *skb)
905 {
906 struct ieee80211_rx_status *rx_status;
907 struct ieee80211_mgmt *mgmt;
908 u16 fc;
909
910 rx_status = IEEE80211_SKB_RXCB(skb);
911 mgmt = (struct ieee80211_mgmt *) skb->data;
912 fc = le16_to_cpu(mgmt->frame_control);
913
914 sdata_lock(sdata);
915
916 if (!sdata->u.ibss.ssid_len)
917 goto mgmt_out; /* not ready to merge yet */
918
919 switch (fc & IEEE80211_FCTL_STYPE) {
920 case IEEE80211_STYPE_PROBE_REQ:
921 ieee80211_rx_mgmt_probe_req(sdata, skb);
922 break;
923 case IEEE80211_STYPE_PROBE_RESP:
924 case IEEE80211_STYPE_BEACON:
925 ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len,
926 rx_status);
927 break;
928 case IEEE80211_STYPE_AUTH:
929 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
930 break;
931 case IEEE80211_STYPE_DEAUTH:
932 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
933 break;
934 }
935
936 mgmt_out:
937 sdata_unlock(sdata);
938 }
939
940 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
941 {
942 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
943 struct sta_info *sta;
944
945 sdata_lock(sdata);
946
947 /*
948 * Work could be scheduled after scan or similar
949 * when we aren't even joined (or trying) with a
950 * network.
951 */
952 if (!ifibss->ssid_len)
953 goto out;
954
955 spin_lock_bh(&ifibss->incomplete_lock);
956 while (!list_empty(&ifibss->incomplete_stations)) {
957 sta = list_first_entry(&ifibss->incomplete_stations,
958 struct sta_info, list);
959 list_del(&sta->list);
960 spin_unlock_bh(&ifibss->incomplete_lock);
961
962 ieee80211_ibss_finish_sta(sta);
963 rcu_read_unlock();
964 spin_lock_bh(&ifibss->incomplete_lock);
965 }
966 spin_unlock_bh(&ifibss->incomplete_lock);
967
968 switch (ifibss->state) {
969 case IEEE80211_IBSS_MLME_SEARCH:
970 ieee80211_sta_find_ibss(sdata);
971 break;
972 case IEEE80211_IBSS_MLME_JOINED:
973 ieee80211_sta_merge_ibss(sdata);
974 break;
975 default:
976 WARN_ON(1);
977 break;
978 }
979
980 out:
981 sdata_unlock(sdata);
982 }
983
984 static void ieee80211_ibss_timer(unsigned long data)
985 {
986 struct ieee80211_sub_if_data *sdata =
987 (struct ieee80211_sub_if_data *) data;
988
989 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
990 }
991
992 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
993 {
994 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
995
996 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
997 (unsigned long) sdata);
998 INIT_LIST_HEAD(&ifibss->incomplete_stations);
999 spin_lock_init(&ifibss->incomplete_lock);
1000 }
1001
1002 /* scan finished notification */
1003 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1004 {
1005 struct ieee80211_sub_if_data *sdata;
1006
1007 mutex_lock(&local->iflist_mtx);
1008 list_for_each_entry(sdata, &local->interfaces, list) {
1009 if (!ieee80211_sdata_running(sdata))
1010 continue;
1011 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1012 continue;
1013 sdata->u.ibss.last_scan_completed = jiffies;
1014 ieee80211_queue_work(&local->hw, &sdata->work);
1015 }
1016 mutex_unlock(&local->iflist_mtx);
1017 }
1018
1019 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1020 struct cfg80211_ibss_params *params)
1021 {
1022 u32 changed = 0;
1023
1024 if (params->bssid) {
1025 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1026 sdata->u.ibss.fixed_bssid = true;
1027 } else
1028 sdata->u.ibss.fixed_bssid = false;
1029
1030 sdata->u.ibss.privacy = params->privacy;
1031 sdata->u.ibss.control_port = params->control_port;
1032 sdata->u.ibss.basic_rates = params->basic_rates;
1033 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1034 sizeof(params->mcast_rate));
1035
1036 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1037
1038 sdata->u.ibss.chandef = params->chandef;
1039 sdata->u.ibss.fixed_channel = params->channel_fixed;
1040
1041 if (params->ie) {
1042 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1043 GFP_KERNEL);
1044 if (sdata->u.ibss.ie)
1045 sdata->u.ibss.ie_len = params->ie_len;
1046 }
1047
1048 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1049 sdata->u.ibss.ibss_join_req = jiffies;
1050
1051 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1052 sdata->u.ibss.ssid_len = params->ssid_len;
1053
1054 /*
1055 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1056 * reserved, but an HT STA shall protect HT transmissions as though
1057 * the HT Protection field were set to non-HT mixed mode.
1058 *
1059 * In an IBSS, the RIFS Mode field of the HT Operation element is
1060 * also reserved, but an HT STA shall operate as though this field
1061 * were set to 1.
1062 */
1063
1064 sdata->vif.bss_conf.ht_operation_mode |=
1065 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1066 | IEEE80211_HT_PARAM_RIFS_MODE;
1067
1068 changed |= BSS_CHANGED_HT;
1069 ieee80211_bss_info_change_notify(sdata, changed);
1070
1071 sdata->smps_mode = IEEE80211_SMPS_OFF;
1072 sdata->needed_rx_chains = sdata->local->rx_chains;
1073
1074 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1075
1076 return 0;
1077 }
1078
1079 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1080 {
1081 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1082 struct ieee80211_local *local = sdata->local;
1083 struct cfg80211_bss *cbss;
1084 u16 capability;
1085 int active_ibss;
1086 struct sta_info *sta;
1087 struct beacon_data *presp;
1088
1089 active_ibss = ieee80211_sta_active_ibss(sdata);
1090
1091 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1092 capability = WLAN_CAPABILITY_IBSS;
1093
1094 if (ifibss->privacy)
1095 capability |= WLAN_CAPABILITY_PRIVACY;
1096
1097 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
1098 ifibss->bssid, ifibss->ssid,
1099 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1100 WLAN_CAPABILITY_PRIVACY,
1101 capability);
1102
1103 if (cbss) {
1104 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1105 cfg80211_put_bss(local->hw.wiphy, cbss);
1106 }
1107 }
1108
1109 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1110 memset(ifibss->bssid, 0, ETH_ALEN);
1111 ifibss->ssid_len = 0;
1112
1113 sta_info_flush(sdata);
1114
1115 spin_lock_bh(&ifibss->incomplete_lock);
1116 while (!list_empty(&ifibss->incomplete_stations)) {
1117 sta = list_first_entry(&ifibss->incomplete_stations,
1118 struct sta_info, list);
1119 list_del(&sta->list);
1120 spin_unlock_bh(&ifibss->incomplete_lock);
1121
1122 sta_info_free(local, sta);
1123 spin_lock_bh(&ifibss->incomplete_lock);
1124 }
1125 spin_unlock_bh(&ifibss->incomplete_lock);
1126
1127 netif_carrier_off(sdata->dev);
1128
1129 /* remove beacon */
1130 kfree(sdata->u.ibss.ie);
1131 presp = rcu_dereference_protected(ifibss->presp,
1132 lockdep_is_held(&sdata->wdev.mtx));
1133 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1134 sdata->vif.bss_conf.ibss_joined = false;
1135 sdata->vif.bss_conf.ibss_creator = false;
1136 sdata->vif.bss_conf.enable_beacon = false;
1137 sdata->vif.bss_conf.ssid_len = 0;
1138 clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
1139 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1140 BSS_CHANGED_IBSS);
1141 synchronize_rcu();
1142 kfree(presp);
1143
1144 skb_queue_purge(&sdata->skb_queue);
1145
1146 del_timer_sync(&sdata->u.ibss.timer);
1147
1148 return 0;
1149 }
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