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Merge branch 'slab/for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penber...
[deliverable/linux.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 sk_buff *skb;
48 struct ieee80211_mgmt *mgmt;
49 u8 *pos;
50 struct ieee80211_supported_band *sband;
51 struct cfg80211_bss *bss;
52 u32 bss_change;
53 u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
54 struct cfg80211_chan_def chandef;
55
56 lockdep_assert_held(&ifibss->mtx);
57
58 /* Reset own TSF to allow time synchronization work. */
59 drv_reset_tsf(local, sdata);
60
61 skb = ifibss->skb;
62 RCU_INIT_POINTER(ifibss->presp, NULL);
63 synchronize_rcu();
64 skb->data = skb->head;
65 skb->len = 0;
66 skb_reset_tail_pointer(skb);
67 skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
68
69 if (!ether_addr_equal(ifibss->bssid, bssid))
70 sta_info_flush(sdata->local, sdata);
71
72 /* if merging, indicate to driver that we leave the old IBSS */
73 if (sdata->vif.bss_conf.ibss_joined) {
74 sdata->vif.bss_conf.ibss_joined = false;
75 sdata->vif.bss_conf.ibss_creator = false;
76 netif_carrier_off(sdata->dev);
77 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
78 }
79
80 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
81
82 cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
83 if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
84 chandef.width = NL80211_CHAN_WIDTH_20;
85 chandef.center_freq1 = chan->center_freq;
86 }
87
88 ieee80211_vif_release_channel(sdata);
89 if (ieee80211_vif_use_channel(sdata, &chandef,
90 ifibss->fixed_channel ?
91 IEEE80211_CHANCTX_SHARED :
92 IEEE80211_CHANCTX_EXCLUSIVE)) {
93 sdata_info(sdata, "Failed to join IBSS, no channel context\n");
94 return;
95 }
96
97 memcpy(ifibss->bssid, bssid, ETH_ALEN);
98
99 sband = local->hw.wiphy->bands[chan->band];
100
101 /* build supported rates array */
102 pos = supp_rates;
103 for (i = 0; i < sband->n_bitrates; i++) {
104 int rate = sband->bitrates[i].bitrate;
105 u8 basic = 0;
106 if (basic_rates & BIT(i))
107 basic = 0x80;
108 *pos++ = basic | (u8) (rate / 5);
109 }
110
111 /* Build IBSS probe response */
112 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
113 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
114 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
115 IEEE80211_STYPE_PROBE_RESP);
116 eth_broadcast_addr(mgmt->da);
117 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
118 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
119 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
120 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
121 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
122
123 pos = skb_put(skb, 2 + ifibss->ssid_len);
124 *pos++ = WLAN_EID_SSID;
125 *pos++ = ifibss->ssid_len;
126 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
127
128 rates = sband->n_bitrates;
129 if (rates > 8)
130 rates = 8;
131 pos = skb_put(skb, 2 + rates);
132 *pos++ = WLAN_EID_SUPP_RATES;
133 *pos++ = rates;
134 memcpy(pos, supp_rates, rates);
135
136 if (sband->band == IEEE80211_BAND_2GHZ) {
137 pos = skb_put(skb, 2 + 1);
138 *pos++ = WLAN_EID_DS_PARAMS;
139 *pos++ = 1;
140 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
141 }
142
143 pos = skb_put(skb, 2 + 2);
144 *pos++ = WLAN_EID_IBSS_PARAMS;
145 *pos++ = 2;
146 /* FIX: set ATIM window based on scan results */
147 *pos++ = 0;
148 *pos++ = 0;
149
150 if (sband->n_bitrates > 8) {
151 rates = sband->n_bitrates - 8;
152 pos = skb_put(skb, 2 + rates);
153 *pos++ = WLAN_EID_EXT_SUPP_RATES;
154 *pos++ = rates;
155 memcpy(pos, &supp_rates[8], rates);
156 }
157
158 if (ifibss->ie_len)
159 memcpy(skb_put(skb, ifibss->ie_len),
160 ifibss->ie, ifibss->ie_len);
161
162 /* add HT capability and information IEs */
163 if (chandef.width != NL80211_CHAN_WIDTH_20_NOHT &&
164 sband->ht_cap.ht_supported) {
165 pos = skb_put(skb, 4 +
166 sizeof(struct ieee80211_ht_cap) +
167 sizeof(struct ieee80211_ht_operation));
168 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
169 sband->ht_cap.cap);
170 /*
171 * Note: According to 802.11n-2009 9.13.3.1, HT Protection
172 * field and RIFS Mode are reserved in IBSS mode, therefore
173 * keep them at 0
174 */
175 pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
176 &chandef, 0);
177 }
178
179 if (local->hw.queues >= IEEE80211_NUM_ACS) {
180 pos = skb_put(skb, 9);
181 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
182 *pos++ = 7; /* len */
183 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
184 *pos++ = 0x50;
185 *pos++ = 0xf2;
186 *pos++ = 2; /* WME */
187 *pos++ = 0; /* WME info */
188 *pos++ = 1; /* WME ver */
189 *pos++ = 0; /* U-APSD no in use */
190 }
191
192 rcu_assign_pointer(ifibss->presp, skb);
193
194 sdata->vif.bss_conf.beacon_int = beacon_int;
195 sdata->vif.bss_conf.basic_rates = basic_rates;
196 bss_change = BSS_CHANGED_BEACON_INT;
197 bss_change |= ieee80211_reset_erp_info(sdata);
198 bss_change |= BSS_CHANGED_BSSID;
199 bss_change |= BSS_CHANGED_BEACON;
200 bss_change |= BSS_CHANGED_BEACON_ENABLED;
201 bss_change |= BSS_CHANGED_BASIC_RATES;
202 bss_change |= BSS_CHANGED_HT;
203 bss_change |= BSS_CHANGED_IBSS;
204
205 /*
206 * In 5 GHz/802.11a, we can always use short slot time.
207 * (IEEE 802.11-2012 18.3.8.7)
208 *
209 * In 2.4GHz, we must always use long slots in IBSS for compatibility
210 * reasons.
211 * (IEEE 802.11-2012 19.4.5)
212 *
213 * HT follows these specifications (IEEE 802.11-2012 20.3.18)
214 */
215 sdata->vif.bss_conf.use_short_slot = chan->band == IEEE80211_BAND_5GHZ;
216 bss_change |= BSS_CHANGED_ERP_SLOT;
217
218 sdata->vif.bss_conf.ibss_joined = true;
219 sdata->vif.bss_conf.ibss_creator = creator;
220 ieee80211_bss_info_change_notify(sdata, bss_change);
221
222 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
223
224 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
225 mod_timer(&ifibss->timer,
226 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
227
228 bss = cfg80211_inform_bss_frame(local->hw.wiphy, chan,
229 mgmt, skb->len, 0, GFP_KERNEL);
230 cfg80211_put_bss(bss);
231 netif_carrier_on(sdata->dev);
232 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
233 }
234
235 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
236 struct ieee80211_bss *bss)
237 {
238 struct cfg80211_bss *cbss =
239 container_of((void *)bss, struct cfg80211_bss, priv);
240 struct ieee80211_supported_band *sband;
241 u32 basic_rates;
242 int i, j;
243 u16 beacon_int = cbss->beacon_interval;
244
245 lockdep_assert_held(&sdata->u.ibss.mtx);
246
247 if (beacon_int < 10)
248 beacon_int = 10;
249
250 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
251
252 basic_rates = 0;
253
254 for (i = 0; i < bss->supp_rates_len; i++) {
255 int rate = (bss->supp_rates[i] & 0x7f) * 5;
256 bool is_basic = !!(bss->supp_rates[i] & 0x80);
257
258 for (j = 0; j < sband->n_bitrates; j++) {
259 if (sband->bitrates[j].bitrate == rate) {
260 if (is_basic)
261 basic_rates |= BIT(j);
262 break;
263 }
264 }
265 }
266
267 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
268 beacon_int,
269 cbss->channel,
270 basic_rates,
271 cbss->capability,
272 cbss->tsf,
273 false);
274 }
275
276 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta,
277 bool auth)
278 __acquires(RCU)
279 {
280 struct ieee80211_sub_if_data *sdata = sta->sdata;
281 u8 addr[ETH_ALEN];
282
283 memcpy(addr, sta->sta.addr, ETH_ALEN);
284
285 ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
286
287 sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
288 sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
289 /* authorize the station only if the network is not RSN protected. If
290 * not wait for the userspace to authorize it */
291 if (!sta->sdata->u.ibss.control_port)
292 sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
293
294 rate_control_rate_init(sta);
295
296 /* If it fails, maybe we raced another insertion? */
297 if (sta_info_insert_rcu(sta))
298 return sta_info_get(sdata, addr);
299 if (auth && !sdata->u.ibss.auth_frame_registrations) {
300 ibss_dbg(sdata,
301 "TX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=1)\n",
302 sdata->vif.addr, addr, sdata->u.ibss.bssid);
303 ieee80211_send_auth(sdata, 1, WLAN_AUTH_OPEN, 0, NULL, 0,
304 addr, sdata->u.ibss.bssid, NULL, 0, 0);
305 }
306 return sta;
307 }
308
309 static struct sta_info *
310 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
311 const u8 *bssid, const u8 *addr,
312 u32 supp_rates, bool auth)
313 __acquires(RCU)
314 {
315 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
316 struct ieee80211_local *local = sdata->local;
317 struct sta_info *sta;
318 struct ieee80211_chanctx_conf *chanctx_conf;
319 int band;
320
321 /*
322 * XXX: Consider removing the least recently used entry and
323 * allow new one to be added.
324 */
325 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
326 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
327 sdata->name, addr);
328 rcu_read_lock();
329 return NULL;
330 }
331
332 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
333 rcu_read_lock();
334 return NULL;
335 }
336
337 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
338 rcu_read_lock();
339 return NULL;
340 }
341
342 rcu_read_lock();
343 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
344 if (WARN_ON_ONCE(!chanctx_conf))
345 return NULL;
346 band = chanctx_conf->def.chan->band;
347 rcu_read_unlock();
348
349 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
350 if (!sta) {
351 rcu_read_lock();
352 return NULL;
353 }
354
355 sta->last_rx = jiffies;
356
357 /* make sure mandatory rates are always added */
358 sta->sta.supp_rates[band] = supp_rates |
359 ieee80211_mandatory_rates(local, band);
360
361 return ieee80211_ibss_finish_sta(sta, auth);
362 }
363
364 static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
365 struct ieee80211_mgmt *mgmt,
366 size_t len)
367 {
368 u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
369
370 if (len < IEEE80211_DEAUTH_FRAME_LEN)
371 return;
372
373 ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM BSSID=%pM (reason: %d)\n",
374 mgmt->sa, mgmt->da, mgmt->bssid, reason);
375 sta_info_destroy_addr(sdata, mgmt->sa);
376 }
377
378 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
379 struct ieee80211_mgmt *mgmt,
380 size_t len)
381 {
382 u16 auth_alg, auth_transaction;
383 struct sta_info *sta;
384 u8 deauth_frame_buf[IEEE80211_DEAUTH_FRAME_LEN];
385
386 lockdep_assert_held(&sdata->u.ibss.mtx);
387
388 if (len < 24 + 6)
389 return;
390
391 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
392 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
393
394 ibss_dbg(sdata,
395 "RX Auth SA=%pM DA=%pM BSSID=%pM (auth_transaction=%d)\n",
396 mgmt->sa, mgmt->da, mgmt->bssid, auth_transaction);
397
398 if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
399 return;
400
401 sta_info_destroy_addr(sdata, mgmt->sa);
402 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, 0, false);
403 rcu_read_unlock();
404
405 /*
406 * if we have any problem in allocating the new station, we reply with a
407 * DEAUTH frame to tell the other end that we had a problem
408 */
409 if (!sta) {
410 ieee80211_send_deauth_disassoc(sdata, sdata->u.ibss.bssid,
411 IEEE80211_STYPE_DEAUTH,
412 WLAN_REASON_UNSPECIFIED, true,
413 deauth_frame_buf);
414 return;
415 }
416
417 /*
418 * IEEE 802.11 standard does not require authentication in IBSS
419 * networks and most implementations do not seem to use it.
420 * However, try to reply to authentication attempts if someone
421 * has actually implemented this.
422 */
423 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
424 mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0);
425 }
426
427 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
428 struct ieee80211_mgmt *mgmt,
429 size_t len,
430 struct ieee80211_rx_status *rx_status,
431 struct ieee802_11_elems *elems,
432 bool beacon)
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 && elems->ds_params_len == 1)
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(local, band);
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, true);
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.channel_type != NL80211_CHAN_NO_HT) {
493 /* we both use HT */
494 struct ieee80211_sta_ht_cap sta_ht_cap_new;
495 struct cfg80211_chan_def chandef;
496
497 ieee80211_ht_oper_to_chandef(channel,
498 elems->ht_operation,
499 &chandef);
500
501 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
502 elems->ht_cap_elem,
503 &sta_ht_cap_new);
504
505 /*
506 * fall back to HT20 if we don't use or use
507 * the other extension channel
508 */
509 if (chandef.width != NL80211_CHAN_WIDTH_40 ||
510 cfg80211_get_chandef_type(&chandef) !=
511 sdata->u.ibss.channel_type)
512 sta_ht_cap_new.cap &=
513 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
514
515 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
516 sizeof(sta_ht_cap_new))) {
517 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
518 sizeof(sta_ht_cap_new));
519 rates_updated = true;
520 }
521 }
522
523 if (sta && rates_updated) {
524 drv_sta_rc_update(local, sdata, &sta->sta,
525 IEEE80211_RC_SUPP_RATES_CHANGED);
526 rate_control_rate_init(sta);
527 }
528
529 rcu_read_unlock();
530 }
531
532 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
533 channel, beacon);
534 if (!bss)
535 return;
536
537 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
538
539 /* was just updated in ieee80211_bss_info_update */
540 beacon_timestamp = cbss->tsf;
541
542 /* check if we need to merge IBSS */
543
544 /* we use a fixed BSSID */
545 if (sdata->u.ibss.fixed_bssid)
546 goto put_bss;
547
548 /* not an IBSS */
549 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
550 goto put_bss;
551
552 /* different channel */
553 if (sdata->u.ibss.fixed_channel &&
554 sdata->u.ibss.channel != cbss->channel)
555 goto put_bss;
556
557 /* different SSID */
558 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
559 memcmp(elems->ssid, sdata->u.ibss.ssid,
560 sdata->u.ibss.ssid_len))
561 goto put_bss;
562
563 /* same BSSID */
564 if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid))
565 goto put_bss;
566
567 if (ieee80211_have_rx_timestamp(rx_status)) {
568 /* time when timestamp field was received */
569 rx_timestamp =
570 ieee80211_calculate_rx_timestamp(local, rx_status,
571 len + FCS_LEN, 24);
572 } else {
573 /*
574 * second best option: get current TSF
575 * (will return -1 if not supported)
576 */
577 rx_timestamp = drv_get_tsf(local, sdata);
578 }
579
580 ibss_dbg(sdata,
581 "RX beacon SA=%pM BSSID=%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
582 mgmt->sa, mgmt->bssid,
583 (unsigned long long)rx_timestamp,
584 (unsigned long long)beacon_timestamp,
585 (unsigned long long)(rx_timestamp - beacon_timestamp),
586 jiffies);
587
588 if (beacon_timestamp > rx_timestamp) {
589 ibss_dbg(sdata,
590 "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n",
591 mgmt->bssid);
592 ieee80211_sta_join_ibss(sdata, bss);
593 supp_rates = ieee80211_sta_get_rates(local, elems, band, NULL);
594 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
595 supp_rates, true);
596 rcu_read_unlock();
597 }
598
599 put_bss:
600 ieee80211_rx_bss_put(local, bss);
601 }
602
603 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
604 const u8 *bssid, const u8 *addr,
605 u32 supp_rates)
606 {
607 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
608 struct ieee80211_local *local = sdata->local;
609 struct sta_info *sta;
610 struct ieee80211_chanctx_conf *chanctx_conf;
611 int band;
612
613 /*
614 * XXX: Consider removing the least recently used entry and
615 * allow new one to be added.
616 */
617 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
618 net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
619 sdata->name, addr);
620 return;
621 }
622
623 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
624 return;
625
626 if (!ether_addr_equal(bssid, sdata->u.ibss.bssid))
627 return;
628
629 rcu_read_lock();
630 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
631 if (WARN_ON_ONCE(!chanctx_conf)) {
632 rcu_read_unlock();
633 return;
634 }
635 band = chanctx_conf->def.chan->band;
636 rcu_read_unlock();
637
638 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
639 if (!sta)
640 return;
641
642 sta->last_rx = jiffies;
643
644 /* make sure mandatory rates are always added */
645 sta->sta.supp_rates[band] = supp_rates |
646 ieee80211_mandatory_rates(local, band);
647
648 spin_lock(&ifibss->incomplete_lock);
649 list_add(&sta->list, &ifibss->incomplete_stations);
650 spin_unlock(&ifibss->incomplete_lock);
651 ieee80211_queue_work(&local->hw, &sdata->work);
652 }
653
654 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
655 {
656 struct ieee80211_local *local = sdata->local;
657 int active = 0;
658 struct sta_info *sta;
659
660 lockdep_assert_held(&sdata->u.ibss.mtx);
661
662 rcu_read_lock();
663
664 list_for_each_entry_rcu(sta, &local->sta_list, list) {
665 if (sta->sdata == sdata &&
666 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
667 jiffies)) {
668 active++;
669 break;
670 }
671 }
672
673 rcu_read_unlock();
674
675 return active;
676 }
677
678 /*
679 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
680 */
681
682 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
683 {
684 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
685
686 lockdep_assert_held(&ifibss->mtx);
687
688 mod_timer(&ifibss->timer,
689 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
690
691 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
692
693 if (time_before(jiffies, ifibss->last_scan_completed +
694 IEEE80211_IBSS_MERGE_INTERVAL))
695 return;
696
697 if (ieee80211_sta_active_ibss(sdata))
698 return;
699
700 if (ifibss->fixed_channel)
701 return;
702
703 sdata_info(sdata,
704 "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n");
705
706 ieee80211_request_internal_scan(sdata,
707 ifibss->ssid, ifibss->ssid_len, NULL);
708 }
709
710 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
711 {
712 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
713 u8 bssid[ETH_ALEN];
714 u16 capability;
715 int i;
716
717 lockdep_assert_held(&ifibss->mtx);
718
719 if (ifibss->fixed_bssid) {
720 memcpy(bssid, ifibss->bssid, ETH_ALEN);
721 } else {
722 /* Generate random, not broadcast, locally administered BSSID. Mix in
723 * own MAC address to make sure that devices that do not have proper
724 * random number generator get different BSSID. */
725 get_random_bytes(bssid, ETH_ALEN);
726 for (i = 0; i < ETH_ALEN; i++)
727 bssid[i] ^= sdata->vif.addr[i];
728 bssid[0] &= ~0x01;
729 bssid[0] |= 0x02;
730 }
731
732 sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid);
733
734 capability = WLAN_CAPABILITY_IBSS;
735
736 if (ifibss->privacy)
737 capability |= WLAN_CAPABILITY_PRIVACY;
738 else
739 sdata->drop_unencrypted = 0;
740
741 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
742 ifibss->channel, ifibss->basic_rates,
743 capability, 0, true);
744 }
745
746 /*
747 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
748 */
749
750 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
751 {
752 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
753 struct ieee80211_local *local = sdata->local;
754 struct cfg80211_bss *cbss;
755 struct ieee80211_channel *chan = NULL;
756 const u8 *bssid = NULL;
757 int active_ibss;
758 u16 capability;
759
760 lockdep_assert_held(&ifibss->mtx);
761
762 active_ibss = ieee80211_sta_active_ibss(sdata);
763 ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss);
764
765 if (active_ibss)
766 return;
767
768 capability = WLAN_CAPABILITY_IBSS;
769 if (ifibss->privacy)
770 capability |= WLAN_CAPABILITY_PRIVACY;
771 if (ifibss->fixed_bssid)
772 bssid = ifibss->bssid;
773 if (ifibss->fixed_channel)
774 chan = ifibss->channel;
775 if (!is_zero_ether_addr(ifibss->bssid))
776 bssid = ifibss->bssid;
777 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
778 ifibss->ssid, ifibss->ssid_len,
779 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
780 capability);
781
782 if (cbss) {
783 struct ieee80211_bss *bss;
784
785 bss = (void *)cbss->priv;
786 ibss_dbg(sdata,
787 "sta_find_ibss: selected %pM current %pM\n",
788 cbss->bssid, ifibss->bssid);
789 sdata_info(sdata,
790 "Selected IBSS BSSID %pM based on configured SSID\n",
791 cbss->bssid);
792
793 ieee80211_sta_join_ibss(sdata, bss);
794 ieee80211_rx_bss_put(local, bss);
795 return;
796 }
797
798 ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n");
799
800 /* Selected IBSS not found in current scan results - try to scan */
801 if (time_after(jiffies, ifibss->last_scan_completed +
802 IEEE80211_SCAN_INTERVAL)) {
803 sdata_info(sdata, "Trigger new scan to find an IBSS to join\n");
804
805 ieee80211_request_internal_scan(sdata,
806 ifibss->ssid, ifibss->ssid_len,
807 ifibss->fixed_channel ? ifibss->channel : NULL);
808 } else {
809 int interval = IEEE80211_SCAN_INTERVAL;
810
811 if (time_after(jiffies, ifibss->ibss_join_req +
812 IEEE80211_IBSS_JOIN_TIMEOUT))
813 ieee80211_sta_create_ibss(sdata);
814
815 mod_timer(&ifibss->timer,
816 round_jiffies(jiffies + interval));
817 }
818 }
819
820 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
821 struct sk_buff *req)
822 {
823 struct ieee80211_mgmt *mgmt = (void *)req->data;
824 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
825 struct ieee80211_local *local = sdata->local;
826 int tx_last_beacon, len = req->len;
827 struct sk_buff *skb;
828 struct ieee80211_mgmt *resp;
829 struct sk_buff *presp;
830 u8 *pos, *end;
831
832 lockdep_assert_held(&ifibss->mtx);
833
834 presp = rcu_dereference_protected(ifibss->presp,
835 lockdep_is_held(&ifibss->mtx));
836
837 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
838 len < 24 + 2 || !presp)
839 return;
840
841 tx_last_beacon = drv_tx_last_beacon(local);
842
843 ibss_dbg(sdata,
844 "RX ProbeReq SA=%pM DA=%pM BSSID=%pM (tx_last_beacon=%d)\n",
845 mgmt->sa, mgmt->da, mgmt->bssid, tx_last_beacon);
846
847 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
848 return;
849
850 if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) &&
851 !is_broadcast_ether_addr(mgmt->bssid))
852 return;
853
854 end = ((u8 *) mgmt) + len;
855 pos = mgmt->u.probe_req.variable;
856 if (pos[0] != WLAN_EID_SSID ||
857 pos + 2 + pos[1] > end) {
858 ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n",
859 mgmt->sa);
860 return;
861 }
862 if (pos[1] != 0 &&
863 (pos[1] != ifibss->ssid_len ||
864 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
865 /* Ignore ProbeReq for foreign SSID */
866 return;
867 }
868
869 /* Reply with ProbeResp */
870 skb = skb_copy(presp, GFP_KERNEL);
871 if (!skb)
872 return;
873
874 resp = (struct ieee80211_mgmt *) skb->data;
875 memcpy(resp->da, mgmt->sa, ETH_ALEN);
876 ibss_dbg(sdata, "Sending ProbeResp to %pM\n", resp->da);
877 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
878 ieee80211_tx_skb(sdata, skb);
879 }
880
881 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
882 struct ieee80211_mgmt *mgmt,
883 size_t len,
884 struct ieee80211_rx_status *rx_status)
885 {
886 size_t baselen;
887 struct ieee802_11_elems elems;
888
889 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
890 if (baselen > len)
891 return;
892
893 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
894 &elems);
895
896 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
897 }
898
899 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
900 struct ieee80211_mgmt *mgmt,
901 size_t len,
902 struct ieee80211_rx_status *rx_status)
903 {
904 size_t baselen;
905 struct ieee802_11_elems elems;
906
907 /* Process beacon from the current BSS */
908 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
909 if (baselen > len)
910 return;
911
912 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
913
914 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
915 }
916
917 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
918 struct sk_buff *skb)
919 {
920 struct ieee80211_rx_status *rx_status;
921 struct ieee80211_mgmt *mgmt;
922 u16 fc;
923
924 rx_status = IEEE80211_SKB_RXCB(skb);
925 mgmt = (struct ieee80211_mgmt *) skb->data;
926 fc = le16_to_cpu(mgmt->frame_control);
927
928 mutex_lock(&sdata->u.ibss.mtx);
929
930 if (!sdata->u.ibss.ssid_len)
931 goto mgmt_out; /* not ready to merge yet */
932
933 switch (fc & IEEE80211_FCTL_STYPE) {
934 case IEEE80211_STYPE_PROBE_REQ:
935 ieee80211_rx_mgmt_probe_req(sdata, skb);
936 break;
937 case IEEE80211_STYPE_PROBE_RESP:
938 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
939 rx_status);
940 break;
941 case IEEE80211_STYPE_BEACON:
942 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
943 rx_status);
944 break;
945 case IEEE80211_STYPE_AUTH:
946 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
947 break;
948 case IEEE80211_STYPE_DEAUTH:
949 ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len);
950 break;
951 }
952
953 mgmt_out:
954 mutex_unlock(&sdata->u.ibss.mtx);
955 }
956
957 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
958 {
959 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
960 struct sta_info *sta;
961
962 mutex_lock(&ifibss->mtx);
963
964 /*
965 * Work could be scheduled after scan or similar
966 * when we aren't even joined (or trying) with a
967 * network.
968 */
969 if (!ifibss->ssid_len)
970 goto out;
971
972 spin_lock_bh(&ifibss->incomplete_lock);
973 while (!list_empty(&ifibss->incomplete_stations)) {
974 sta = list_first_entry(&ifibss->incomplete_stations,
975 struct sta_info, list);
976 list_del(&sta->list);
977 spin_unlock_bh(&ifibss->incomplete_lock);
978
979 ieee80211_ibss_finish_sta(sta, true);
980 rcu_read_unlock();
981 spin_lock_bh(&ifibss->incomplete_lock);
982 }
983 spin_unlock_bh(&ifibss->incomplete_lock);
984
985 switch (ifibss->state) {
986 case IEEE80211_IBSS_MLME_SEARCH:
987 ieee80211_sta_find_ibss(sdata);
988 break;
989 case IEEE80211_IBSS_MLME_JOINED:
990 ieee80211_sta_merge_ibss(sdata);
991 break;
992 default:
993 WARN_ON(1);
994 break;
995 }
996
997 out:
998 mutex_unlock(&ifibss->mtx);
999 }
1000
1001 static void ieee80211_ibss_timer(unsigned long data)
1002 {
1003 struct ieee80211_sub_if_data *sdata =
1004 (struct ieee80211_sub_if_data *) data;
1005 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1006 struct ieee80211_local *local = sdata->local;
1007
1008 if (local->quiescing) {
1009 ifibss->timer_running = true;
1010 return;
1011 }
1012
1013 ieee80211_queue_work(&local->hw, &sdata->work);
1014 }
1015
1016 #ifdef CONFIG_PM
1017 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
1018 {
1019 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1020
1021 if (del_timer_sync(&ifibss->timer))
1022 ifibss->timer_running = true;
1023 }
1024
1025 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
1026 {
1027 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1028
1029 if (ifibss->timer_running) {
1030 add_timer(&ifibss->timer);
1031 ifibss->timer_running = false;
1032 }
1033 }
1034 #endif
1035
1036 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1037 {
1038 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1039
1040 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1041 (unsigned long) sdata);
1042 mutex_init(&ifibss->mtx);
1043 INIT_LIST_HEAD(&ifibss->incomplete_stations);
1044 spin_lock_init(&ifibss->incomplete_lock);
1045 }
1046
1047 /* scan finished notification */
1048 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1049 {
1050 struct ieee80211_sub_if_data *sdata;
1051
1052 mutex_lock(&local->iflist_mtx);
1053 list_for_each_entry(sdata, &local->interfaces, list) {
1054 if (!ieee80211_sdata_running(sdata))
1055 continue;
1056 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1057 continue;
1058 sdata->u.ibss.last_scan_completed = jiffies;
1059 ieee80211_queue_work(&local->hw, &sdata->work);
1060 }
1061 mutex_unlock(&local->iflist_mtx);
1062 }
1063
1064 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1065 struct cfg80211_ibss_params *params)
1066 {
1067 struct sk_buff *skb;
1068 u32 changed = 0;
1069
1070 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1071 sizeof(struct ieee80211_hdr_3addr) +
1072 12 /* struct ieee80211_mgmt.u.beacon */ +
1073 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1074 2 + 8 /* max Supported Rates */ +
1075 3 /* max DS params */ +
1076 4 /* IBSS params */ +
1077 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1078 2 + sizeof(struct ieee80211_ht_cap) +
1079 2 + sizeof(struct ieee80211_ht_operation) +
1080 params->ie_len);
1081 if (!skb)
1082 return -ENOMEM;
1083
1084 mutex_lock(&sdata->u.ibss.mtx);
1085
1086 if (params->bssid) {
1087 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1088 sdata->u.ibss.fixed_bssid = true;
1089 } else
1090 sdata->u.ibss.fixed_bssid = false;
1091
1092 sdata->u.ibss.privacy = params->privacy;
1093 sdata->u.ibss.control_port = params->control_port;
1094 sdata->u.ibss.basic_rates = params->basic_rates;
1095 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1096 sizeof(params->mcast_rate));
1097
1098 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1099
1100 sdata->u.ibss.channel = params->chandef.chan;
1101 sdata->u.ibss.channel_type =
1102 cfg80211_get_chandef_type(&params->chandef);
1103 sdata->u.ibss.fixed_channel = params->channel_fixed;
1104
1105 if (params->ie) {
1106 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1107 GFP_KERNEL);
1108 if (sdata->u.ibss.ie)
1109 sdata->u.ibss.ie_len = params->ie_len;
1110 }
1111
1112 sdata->u.ibss.skb = skb;
1113 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1114 sdata->u.ibss.ibss_join_req = jiffies;
1115
1116 memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len);
1117 sdata->u.ibss.ssid_len = params->ssid_len;
1118
1119 mutex_unlock(&sdata->u.ibss.mtx);
1120
1121 mutex_lock(&sdata->local->mtx);
1122 ieee80211_recalc_idle(sdata->local);
1123 mutex_unlock(&sdata->local->mtx);
1124
1125 /*
1126 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1127 * reserved, but an HT STA shall protect HT transmissions as though
1128 * the HT Protection field were set to non-HT mixed mode.
1129 *
1130 * In an IBSS, the RIFS Mode field of the HT Operation element is
1131 * also reserved, but an HT STA shall operate as though this field
1132 * were set to 1.
1133 */
1134
1135 sdata->vif.bss_conf.ht_operation_mode |=
1136 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1137 | IEEE80211_HT_PARAM_RIFS_MODE;
1138
1139 changed |= BSS_CHANGED_HT;
1140 ieee80211_bss_info_change_notify(sdata, changed);
1141
1142 sdata->smps_mode = IEEE80211_SMPS_OFF;
1143 sdata->needed_rx_chains = sdata->local->rx_chains;
1144
1145 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1146
1147 return 0;
1148 }
1149
1150 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1151 {
1152 struct sk_buff *skb;
1153 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1154 struct ieee80211_local *local = sdata->local;
1155 struct cfg80211_bss *cbss;
1156 u16 capability;
1157 int active_ibss;
1158 struct sta_info *sta;
1159
1160 mutex_lock(&sdata->u.ibss.mtx);
1161
1162 active_ibss = ieee80211_sta_active_ibss(sdata);
1163
1164 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1165 capability = WLAN_CAPABILITY_IBSS;
1166
1167 if (ifibss->privacy)
1168 capability |= WLAN_CAPABILITY_PRIVACY;
1169
1170 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1171 ifibss->bssid, ifibss->ssid,
1172 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1173 WLAN_CAPABILITY_PRIVACY,
1174 capability);
1175
1176 if (cbss) {
1177 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1178 cfg80211_put_bss(cbss);
1179 }
1180 }
1181
1182 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
1183 memset(ifibss->bssid, 0, ETH_ALEN);
1184 ifibss->ssid_len = 0;
1185
1186 sta_info_flush(sdata->local, sdata);
1187
1188 spin_lock_bh(&ifibss->incomplete_lock);
1189 while (!list_empty(&ifibss->incomplete_stations)) {
1190 sta = list_first_entry(&ifibss->incomplete_stations,
1191 struct sta_info, list);
1192 list_del(&sta->list);
1193 spin_unlock_bh(&ifibss->incomplete_lock);
1194
1195 sta_info_free(local, sta);
1196 spin_lock_bh(&ifibss->incomplete_lock);
1197 }
1198 spin_unlock_bh(&ifibss->incomplete_lock);
1199
1200 netif_carrier_off(sdata->dev);
1201
1202 /* remove beacon */
1203 kfree(sdata->u.ibss.ie);
1204 skb = rcu_dereference_protected(sdata->u.ibss.presp,
1205 lockdep_is_held(&sdata->u.ibss.mtx));
1206 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1207 sdata->vif.bss_conf.ibss_joined = false;
1208 sdata->vif.bss_conf.ibss_creator = false;
1209 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1210 BSS_CHANGED_IBSS);
1211 synchronize_rcu();
1212 kfree_skb(skb);
1213
1214 skb_queue_purge(&sdata->skb_queue);
1215
1216 del_timer_sync(&sdata->u.ibss.timer);
1217
1218 mutex_unlock(&sdata->u.ibss.mtx);
1219
1220 mutex_lock(&local->mtx);
1221 ieee80211_recalc_idle(sdata->local);
1222 mutex_unlock(&local->mtx);
1223
1224 return 0;
1225 }
Linux kernel - Deliverables
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