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mac80211: delay IBSS station insertion
[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 #include <asm/unaligned.h>
24
25 #include "ieee80211_i.h"
26 #include "driver-ops.h"
27 #include "rate.h"
28
29 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
30 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * HZ)
31 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
32
33 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
34 #define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
35
36 #define IEEE80211_IBSS_MAX_STA_ENTRIES 128
37
38
39 static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
40 struct ieee80211_mgmt *mgmt,
41 size_t len)
42 {
43 u16 auth_alg, auth_transaction;
44
45 lockdep_assert_held(&sdata->u.ibss.mtx);
46
47 if (len < 24 + 6)
48 return;
49
50 auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
51 auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
52
53 /*
54 * IEEE 802.11 standard does not require authentication in IBSS
55 * networks and most implementations do not seem to use it.
56 * However, try to reply to authentication attempts if someone
57 * has actually implemented this.
58 */
59 if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
60 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
61 sdata->u.ibss.bssid, NULL, 0, 0);
62 }
63
64 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
65 const u8 *bssid, const int beacon_int,
66 struct ieee80211_channel *chan,
67 const u32 basic_rates,
68 const u16 capability, u64 tsf)
69 {
70 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
71 struct ieee80211_local *local = sdata->local;
72 int rates, i;
73 struct sk_buff *skb;
74 struct ieee80211_mgmt *mgmt;
75 u8 *pos;
76 struct ieee80211_supported_band *sband;
77 struct cfg80211_bss *bss;
78 u32 bss_change;
79 u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
80 enum nl80211_channel_type channel_type;
81
82 lockdep_assert_held(&ifibss->mtx);
83
84 /* Reset own TSF to allow time synchronization work. */
85 drv_reset_tsf(local, sdata);
86
87 skb = ifibss->skb;
88 RCU_INIT_POINTER(ifibss->presp, NULL);
89 synchronize_rcu();
90 skb->data = skb->head;
91 skb->len = 0;
92 skb_reset_tail_pointer(skb);
93 skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
94
95 if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
96 sta_info_flush(sdata->local, sdata);
97
98 /* if merging, indicate to driver that we leave the old IBSS */
99 if (sdata->vif.bss_conf.ibss_joined) {
100 sdata->vif.bss_conf.ibss_joined = false;
101 netif_carrier_off(sdata->dev);
102 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
103 }
104
105 memcpy(ifibss->bssid, bssid, ETH_ALEN);
106
107 sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
108
109 channel_type = ifibss->channel_type;
110 if (channel_type > NL80211_CHAN_HT20 &&
111 !cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
112 channel_type = NL80211_CHAN_HT20;
113 if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
114 /* can only fail due to HT40+/- mismatch */
115 channel_type = NL80211_CHAN_HT20;
116 WARN_ON(!ieee80211_set_channel_type(local, sdata,
117 NL80211_CHAN_HT20));
118 }
119 ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
120
121 sband = local->hw.wiphy->bands[chan->band];
122
123 /* build supported rates array */
124 pos = supp_rates;
125 for (i = 0; i < sband->n_bitrates; i++) {
126 int rate = sband->bitrates[i].bitrate;
127 u8 basic = 0;
128 if (basic_rates & BIT(i))
129 basic = 0x80;
130 *pos++ = basic | (u8) (rate / 5);
131 }
132
133 /* Build IBSS probe response */
134 mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
135 memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
136 mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
137 IEEE80211_STYPE_PROBE_RESP);
138 memset(mgmt->da, 0xff, ETH_ALEN);
139 memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
140 memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
141 mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
142 mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
143 mgmt->u.beacon.capab_info = cpu_to_le16(capability);
144
145 pos = skb_put(skb, 2 + ifibss->ssid_len);
146 *pos++ = WLAN_EID_SSID;
147 *pos++ = ifibss->ssid_len;
148 memcpy(pos, ifibss->ssid, ifibss->ssid_len);
149
150 rates = sband->n_bitrates;
151 if (rates > 8)
152 rates = 8;
153 pos = skb_put(skb, 2 + rates);
154 *pos++ = WLAN_EID_SUPP_RATES;
155 *pos++ = rates;
156 memcpy(pos, supp_rates, rates);
157
158 if (sband->band == IEEE80211_BAND_2GHZ) {
159 pos = skb_put(skb, 2 + 1);
160 *pos++ = WLAN_EID_DS_PARAMS;
161 *pos++ = 1;
162 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
163 }
164
165 pos = skb_put(skb, 2 + 2);
166 *pos++ = WLAN_EID_IBSS_PARAMS;
167 *pos++ = 2;
168 /* FIX: set ATIM window based on scan results */
169 *pos++ = 0;
170 *pos++ = 0;
171
172 if (sband->n_bitrates > 8) {
173 rates = sband->n_bitrates - 8;
174 pos = skb_put(skb, 2 + rates);
175 *pos++ = WLAN_EID_EXT_SUPP_RATES;
176 *pos++ = rates;
177 memcpy(pos, &supp_rates[8], rates);
178 }
179
180 if (ifibss->ie_len)
181 memcpy(skb_put(skb, ifibss->ie_len),
182 ifibss->ie, ifibss->ie_len);
183
184 /* add HT capability and information IEs */
185 if (channel_type && sband->ht_cap.ht_supported) {
186 pos = skb_put(skb, 4 +
187 sizeof(struct ieee80211_ht_cap) +
188 sizeof(struct ieee80211_ht_info));
189 pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
190 sband->ht_cap.cap);
191 pos = ieee80211_ie_build_ht_info(pos,
192 &sband->ht_cap,
193 chan,
194 channel_type);
195 }
196
197 if (local->hw.queues >= 4) {
198 pos = skb_put(skb, 9);
199 *pos++ = WLAN_EID_VENDOR_SPECIFIC;
200 *pos++ = 7; /* len */
201 *pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
202 *pos++ = 0x50;
203 *pos++ = 0xf2;
204 *pos++ = 2; /* WME */
205 *pos++ = 0; /* WME info */
206 *pos++ = 1; /* WME ver */
207 *pos++ = 0; /* U-APSD no in use */
208 }
209
210 RCU_INIT_POINTER(ifibss->presp, skb);
211
212 sdata->vif.bss_conf.beacon_int = beacon_int;
213 sdata->vif.bss_conf.basic_rates = basic_rates;
214 bss_change = BSS_CHANGED_BEACON_INT;
215 bss_change |= ieee80211_reset_erp_info(sdata);
216 bss_change |= BSS_CHANGED_BSSID;
217 bss_change |= BSS_CHANGED_BEACON;
218 bss_change |= BSS_CHANGED_BEACON_ENABLED;
219 bss_change |= BSS_CHANGED_BASIC_RATES;
220 bss_change |= BSS_CHANGED_HT;
221 bss_change |= BSS_CHANGED_IBSS;
222 sdata->vif.bss_conf.ibss_joined = true;
223 ieee80211_bss_info_change_notify(sdata, bss_change);
224
225 ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
226
227 ifibss->state = IEEE80211_IBSS_MLME_JOINED;
228 mod_timer(&ifibss->timer,
229 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
230
231 bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
232 mgmt, skb->len, 0, GFP_KERNEL);
233 cfg80211_put_bss(bss);
234 netif_carrier_on(sdata->dev);
235 cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
236 }
237
238 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
239 struct ieee80211_bss *bss)
240 {
241 struct cfg80211_bss *cbss =
242 container_of((void *)bss, struct cfg80211_bss, priv);
243 struct ieee80211_supported_band *sband;
244 u32 basic_rates;
245 int i, j;
246 u16 beacon_int = cbss->beacon_interval;
247
248 lockdep_assert_held(&sdata->u.ibss.mtx);
249
250 if (beacon_int < 10)
251 beacon_int = 10;
252
253 sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
254
255 basic_rates = 0;
256
257 for (i = 0; i < bss->supp_rates_len; i++) {
258 int rate = (bss->supp_rates[i] & 0x7f) * 5;
259 bool is_basic = !!(bss->supp_rates[i] & 0x80);
260
261 for (j = 0; j < sband->n_bitrates; j++) {
262 if (sband->bitrates[j].bitrate == rate) {
263 if (is_basic)
264 basic_rates |= BIT(j);
265 break;
266 }
267 }
268 }
269
270 __ieee80211_sta_join_ibss(sdata, cbss->bssid,
271 beacon_int,
272 cbss->channel,
273 basic_rates,
274 cbss->capability,
275 cbss->tsf);
276 }
277
278 static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
279 __acquires(RCU)
280 {
281 struct ieee80211_sub_if_data *sdata = sta->sdata;
282 u8 addr[ETH_ALEN];
283
284 memcpy(addr, sta->sta.addr, ETH_ALEN);
285
286 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
287 wiphy_debug(sdata->local->hw.wiphy,
288 "Adding new IBSS station %pM (dev=%s)\n",
289 addr, sdata->name);
290 #endif
291
292 sta_info_move_state(sta, IEEE80211_STA_AUTH);
293 sta_info_move_state(sta, IEEE80211_STA_ASSOC);
294 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
295
296 rate_control_rate_init(sta);
297
298 /* If it fails, maybe we raced another insertion? */
299 if (sta_info_insert_rcu(sta))
300 return sta_info_get(sdata, addr);
301 return sta;
302 }
303
304 static struct sta_info *
305 ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
306 const u8 *bssid, const u8 *addr,
307 u32 supp_rates)
308 __acquires(RCU)
309 {
310 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
311 struct ieee80211_local *local = sdata->local;
312 struct sta_info *sta;
313 int band = local->hw.conf.channel->band;
314
315 /*
316 * XXX: Consider removing the least recently used entry and
317 * allow new one to be added.
318 */
319 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
320 if (net_ratelimit())
321 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
322 sdata->name, addr);
323 rcu_read_lock();
324 return NULL;
325 }
326
327 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
328 rcu_read_lock();
329 return NULL;
330 }
331
332 if (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
333 rcu_read_lock();
334 return NULL;
335 }
336
337 sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
338 if (!sta) {
339 rcu_read_lock();
340 return NULL;
341 }
342
343 sta->last_rx = jiffies;
344
345 /* make sure mandatory rates are always added */
346 sta->sta.supp_rates[band] = supp_rates |
347 ieee80211_mandatory_rates(local, band);
348
349 return ieee80211_ibss_finish_sta(sta);
350 }
351
352 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
353 struct ieee80211_mgmt *mgmt,
354 size_t len,
355 struct ieee80211_rx_status *rx_status,
356 struct ieee802_11_elems *elems,
357 bool beacon)
358 {
359 struct ieee80211_local *local = sdata->local;
360 int freq;
361 struct cfg80211_bss *cbss;
362 struct ieee80211_bss *bss;
363 struct sta_info *sta;
364 struct ieee80211_channel *channel;
365 u64 beacon_timestamp, rx_timestamp;
366 u32 supp_rates = 0;
367 enum ieee80211_band band = rx_status->band;
368 struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
369 bool rates_updated = false;
370
371 if (elems->ds_params && elems->ds_params_len == 1)
372 freq = ieee80211_channel_to_frequency(elems->ds_params[0],
373 band);
374 else
375 freq = rx_status->freq;
376
377 channel = ieee80211_get_channel(local->hw.wiphy, freq);
378
379 if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
380 return;
381
382 if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
383 memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
384
385 rcu_read_lock();
386 sta = sta_info_get(sdata, mgmt->sa);
387
388 if (elems->supp_rates) {
389 supp_rates = ieee80211_sta_get_rates(local, elems,
390 band);
391 if (sta) {
392 u32 prev_rates;
393
394 prev_rates = sta->sta.supp_rates[band];
395 /* make sure mandatory rates are always added */
396 sta->sta.supp_rates[band] = supp_rates |
397 ieee80211_mandatory_rates(local, band);
398
399 if (sta->sta.supp_rates[band] != prev_rates) {
400 #ifdef CONFIG_MAC80211_IBSS_DEBUG
401 printk(KERN_DEBUG
402 "%s: updated supp_rates set "
403 "for %pM based on beacon"
404 "/probe_resp (0x%x -> 0x%x)\n",
405 sdata->name, sta->sta.addr,
406 prev_rates,
407 sta->sta.supp_rates[band]);
408 #endif
409 rates_updated = true;
410 }
411 } else {
412 rcu_read_unlock();
413 sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
414 mgmt->sa, supp_rates);
415 }
416 }
417
418 if (sta && elems->wmm_info)
419 set_sta_flag(sta, WLAN_STA_WME);
420
421 if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
422 sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
423 /* we both use HT */
424 struct ieee80211_sta_ht_cap sta_ht_cap_new;
425 enum nl80211_channel_type channel_type =
426 ieee80211_ht_info_to_channel_type(
427 elems->ht_info_elem);
428
429 ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
430 elems->ht_cap_elem,
431 &sta_ht_cap_new);
432
433 /*
434 * fall back to HT20 if we don't use or use
435 * the other extension channel
436 */
437 if ((channel_type == NL80211_CHAN_HT40MINUS ||
438 channel_type == NL80211_CHAN_HT40PLUS) &&
439 channel_type != sdata->u.ibss.channel_type)
440 sta_ht_cap_new.cap &=
441 ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
442
443 if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
444 sizeof(sta_ht_cap_new))) {
445 memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
446 sizeof(sta_ht_cap_new));
447 rates_updated = true;
448 }
449 }
450
451 if (sta && rates_updated)
452 rate_control_rate_init(sta);
453
454 rcu_read_unlock();
455 }
456
457 bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
458 channel, beacon);
459 if (!bss)
460 return;
461
462 cbss = container_of((void *)bss, struct cfg80211_bss, priv);
463
464 /* was just updated in ieee80211_bss_info_update */
465 beacon_timestamp = cbss->tsf;
466
467 /* check if we need to merge IBSS */
468
469 /* we use a fixed BSSID */
470 if (sdata->u.ibss.fixed_bssid)
471 goto put_bss;
472
473 /* not an IBSS */
474 if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
475 goto put_bss;
476
477 /* different channel */
478 if (cbss->channel != local->oper_channel)
479 goto put_bss;
480
481 /* different SSID */
482 if (elems->ssid_len != sdata->u.ibss.ssid_len ||
483 memcmp(elems->ssid, sdata->u.ibss.ssid,
484 sdata->u.ibss.ssid_len))
485 goto put_bss;
486
487 /* same BSSID */
488 if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
489 goto put_bss;
490
491 if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
492 /*
493 * For correct IBSS merging we need mactime; since mactime is
494 * defined as the time the first data symbol of the frame hits
495 * the PHY, and the timestamp of the beacon is defined as "the
496 * time that the data symbol containing the first bit of the
497 * timestamp is transmitted to the PHY plus the transmitting
498 * STA's delays through its local PHY from the MAC-PHY
499 * interface to its interface with the WM" (802.11 11.1.2)
500 * - equals the time this bit arrives at the receiver - we have
501 * to take into account the offset between the two.
502 *
503 * E.g. at 1 MBit that means mactime is 192 usec earlier
504 * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
505 */
506 int rate;
507
508 if (rx_status->flag & RX_FLAG_HT)
509 rate = 65; /* TODO: HT rates */
510 else
511 rate = local->hw.wiphy->bands[band]->
512 bitrates[rx_status->rate_idx].bitrate;
513
514 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
515 } else {
516 /*
517 * second best option: get current TSF
518 * (will return -1 if not supported)
519 */
520 rx_timestamp = drv_get_tsf(local, sdata);
521 }
522
523 #ifdef CONFIG_MAC80211_IBSS_DEBUG
524 printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
525 "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
526 mgmt->sa, mgmt->bssid,
527 (unsigned long long)rx_timestamp,
528 (unsigned long long)beacon_timestamp,
529 (unsigned long long)(rx_timestamp - beacon_timestamp),
530 jiffies);
531 #endif
532
533 if (beacon_timestamp > rx_timestamp) {
534 #ifdef CONFIG_MAC80211_IBSS_DEBUG
535 printk(KERN_DEBUG "%s: beacon TSF higher than "
536 "local TSF - IBSS merge with BSSID %pM\n",
537 sdata->name, mgmt->bssid);
538 #endif
539 ieee80211_sta_join_ibss(sdata, bss);
540 supp_rates = ieee80211_sta_get_rates(local, elems, band);
541 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
542 supp_rates);
543 rcu_read_unlock();
544 }
545
546 put_bss:
547 ieee80211_rx_bss_put(local, bss);
548 }
549
550 void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
551 const u8 *bssid, const u8 *addr,
552 u32 supp_rates)
553 {
554 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
555 struct ieee80211_local *local = sdata->local;
556 struct sta_info *sta;
557 int band = local->hw.conf.channel->band;
558
559 /*
560 * XXX: Consider removing the least recently used entry and
561 * allow new one to be added.
562 */
563 if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
564 if (net_ratelimit())
565 printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
566 sdata->name, addr);
567 return;
568 }
569
570 if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
571 return;
572
573 if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
574 return;
575
576 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
577 if (!sta)
578 return;
579
580 sta->last_rx = jiffies;
581
582 /* make sure mandatory rates are always added */
583 sta->sta.supp_rates[band] = supp_rates |
584 ieee80211_mandatory_rates(local, band);
585
586 spin_lock(&ifibss->incomplete_lock);
587 list_add(&sta->list, &ifibss->incomplete_stations);
588 spin_unlock(&ifibss->incomplete_lock);
589 ieee80211_queue_work(&local->hw, &sdata->work);
590 }
591
592 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
593 {
594 struct ieee80211_local *local = sdata->local;
595 int active = 0;
596 struct sta_info *sta;
597
598 lockdep_assert_held(&sdata->u.ibss.mtx);
599
600 rcu_read_lock();
601
602 list_for_each_entry_rcu(sta, &local->sta_list, list) {
603 if (sta->sdata == sdata &&
604 time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
605 jiffies)) {
606 active++;
607 break;
608 }
609 }
610
611 rcu_read_unlock();
612
613 return active;
614 }
615
616 /*
617 * This function is called with state == IEEE80211_IBSS_MLME_JOINED
618 */
619
620 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
621 {
622 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
623
624 lockdep_assert_held(&ifibss->mtx);
625
626 mod_timer(&ifibss->timer,
627 round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
628
629 ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
630
631 if (time_before(jiffies, ifibss->last_scan_completed +
632 IEEE80211_IBSS_MERGE_INTERVAL))
633 return;
634
635 if (ieee80211_sta_active_ibss(sdata))
636 return;
637
638 if (ifibss->fixed_channel)
639 return;
640
641 printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
642 "IBSS networks with same SSID (merge)\n", sdata->name);
643
644 ieee80211_request_internal_scan(sdata,
645 ifibss->ssid, ifibss->ssid_len,
646 ifibss->fixed_channel ? ifibss->channel : NULL);
647 }
648
649 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
650 {
651 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
652 u8 bssid[ETH_ALEN];
653 u16 capability;
654 int i;
655
656 lockdep_assert_held(&ifibss->mtx);
657
658 if (ifibss->fixed_bssid) {
659 memcpy(bssid, ifibss->bssid, ETH_ALEN);
660 } else {
661 /* Generate random, not broadcast, locally administered BSSID. Mix in
662 * own MAC address to make sure that devices that do not have proper
663 * random number generator get different BSSID. */
664 get_random_bytes(bssid, ETH_ALEN);
665 for (i = 0; i < ETH_ALEN; i++)
666 bssid[i] ^= sdata->vif.addr[i];
667 bssid[0] &= ~0x01;
668 bssid[0] |= 0x02;
669 }
670
671 printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
672 sdata->name, bssid);
673
674 capability = WLAN_CAPABILITY_IBSS;
675
676 if (ifibss->privacy)
677 capability |= WLAN_CAPABILITY_PRIVACY;
678 else
679 sdata->drop_unencrypted = 0;
680
681 __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
682 ifibss->channel, ifibss->basic_rates,
683 capability, 0);
684 }
685
686 /*
687 * This function is called with state == IEEE80211_IBSS_MLME_SEARCH
688 */
689
690 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
691 {
692 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
693 struct ieee80211_local *local = sdata->local;
694 struct cfg80211_bss *cbss;
695 struct ieee80211_channel *chan = NULL;
696 const u8 *bssid = NULL;
697 int active_ibss;
698 u16 capability;
699
700 lockdep_assert_held(&ifibss->mtx);
701
702 active_ibss = ieee80211_sta_active_ibss(sdata);
703 #ifdef CONFIG_MAC80211_IBSS_DEBUG
704 printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
705 sdata->name, active_ibss);
706 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
707
708 if (active_ibss)
709 return;
710
711 capability = WLAN_CAPABILITY_IBSS;
712 if (ifibss->privacy)
713 capability |= WLAN_CAPABILITY_PRIVACY;
714 if (ifibss->fixed_bssid)
715 bssid = ifibss->bssid;
716 if (ifibss->fixed_channel)
717 chan = ifibss->channel;
718 if (!is_zero_ether_addr(ifibss->bssid))
719 bssid = ifibss->bssid;
720 cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
721 ifibss->ssid, ifibss->ssid_len,
722 WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
723 capability);
724
725 if (cbss) {
726 struct ieee80211_bss *bss;
727
728 bss = (void *)cbss->priv;
729 #ifdef CONFIG_MAC80211_IBSS_DEBUG
730 printk(KERN_DEBUG " sta_find_ibss: selected %pM current "
731 "%pM\n", cbss->bssid, ifibss->bssid);
732 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
733
734 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
735 " based on configured SSID\n",
736 sdata->name, cbss->bssid);
737
738 ieee80211_sta_join_ibss(sdata, bss);
739 ieee80211_rx_bss_put(local, bss);
740 return;
741 }
742
743 #ifdef CONFIG_MAC80211_IBSS_DEBUG
744 printk(KERN_DEBUG " did not try to join ibss\n");
745 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
746
747 /* Selected IBSS not found in current scan results - try to scan */
748 if (time_after(jiffies, ifibss->last_scan_completed +
749 IEEE80211_SCAN_INTERVAL)) {
750 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
751 "join\n", sdata->name);
752
753 ieee80211_request_internal_scan(sdata,
754 ifibss->ssid, ifibss->ssid_len,
755 ifibss->fixed_channel ? ifibss->channel : NULL);
756 } else {
757 int interval = IEEE80211_SCAN_INTERVAL;
758
759 if (time_after(jiffies, ifibss->ibss_join_req +
760 IEEE80211_IBSS_JOIN_TIMEOUT)) {
761 if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
762 ieee80211_sta_create_ibss(sdata);
763 return;
764 }
765 printk(KERN_DEBUG "%s: IBSS not allowed on"
766 " %d MHz\n", sdata->name,
767 local->hw.conf.channel->center_freq);
768
769 /* No IBSS found - decrease scan interval and continue
770 * scanning. */
771 interval = IEEE80211_SCAN_INTERVAL_SLOW;
772 }
773
774 mod_timer(&ifibss->timer,
775 round_jiffies(jiffies + interval));
776 }
777 }
778
779 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
780 struct sk_buff *req)
781 {
782 struct ieee80211_mgmt *mgmt = (void *)req->data;
783 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
784 struct ieee80211_local *local = sdata->local;
785 int tx_last_beacon, len = req->len;
786 struct sk_buff *skb;
787 struct ieee80211_mgmt *resp;
788 struct sk_buff *presp;
789 u8 *pos, *end;
790
791 lockdep_assert_held(&ifibss->mtx);
792
793 presp = rcu_dereference_protected(ifibss->presp,
794 lockdep_is_held(&ifibss->mtx));
795
796 if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
797 len < 24 + 2 || !presp)
798 return;
799
800 tx_last_beacon = drv_tx_last_beacon(local);
801
802 #ifdef CONFIG_MAC80211_IBSS_DEBUG
803 printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
804 " (tx_last_beacon=%d)\n",
805 sdata->name, mgmt->sa, mgmt->da,
806 mgmt->bssid, tx_last_beacon);
807 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
808
809 if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
810 return;
811
812 if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
813 memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
814 return;
815
816 end = ((u8 *) mgmt) + len;
817 pos = mgmt->u.probe_req.variable;
818 if (pos[0] != WLAN_EID_SSID ||
819 pos + 2 + pos[1] > end) {
820 #ifdef CONFIG_MAC80211_IBSS_DEBUG
821 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
822 "from %pM\n",
823 sdata->name, mgmt->sa);
824 #endif
825 return;
826 }
827 if (pos[1] != 0 &&
828 (pos[1] != ifibss->ssid_len ||
829 memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
830 /* Ignore ProbeReq for foreign SSID */
831 return;
832 }
833
834 /* Reply with ProbeResp */
835 skb = skb_copy(presp, GFP_KERNEL);
836 if (!skb)
837 return;
838
839 resp = (struct ieee80211_mgmt *) skb->data;
840 memcpy(resp->da, mgmt->sa, ETH_ALEN);
841 #ifdef CONFIG_MAC80211_IBSS_DEBUG
842 printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
843 sdata->name, resp->da);
844 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
845 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
846 ieee80211_tx_skb(sdata, skb);
847 }
848
849 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
850 struct ieee80211_mgmt *mgmt,
851 size_t len,
852 struct ieee80211_rx_status *rx_status)
853 {
854 size_t baselen;
855 struct ieee802_11_elems elems;
856
857 if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
858 return; /* ignore ProbeResp to foreign address */
859
860 baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
861 if (baselen > len)
862 return;
863
864 ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
865 &elems);
866
867 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
868 }
869
870 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
871 struct ieee80211_mgmt *mgmt,
872 size_t len,
873 struct ieee80211_rx_status *rx_status)
874 {
875 size_t baselen;
876 struct ieee802_11_elems elems;
877
878 /* Process beacon from the current BSS */
879 baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
880 if (baselen > len)
881 return;
882
883 ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
884
885 ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
886 }
887
888 void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
889 struct sk_buff *skb)
890 {
891 struct ieee80211_rx_status *rx_status;
892 struct ieee80211_mgmt *mgmt;
893 u16 fc;
894
895 rx_status = IEEE80211_SKB_RXCB(skb);
896 mgmt = (struct ieee80211_mgmt *) skb->data;
897 fc = le16_to_cpu(mgmt->frame_control);
898
899 mutex_lock(&sdata->u.ibss.mtx);
900
901 if (!sdata->u.ibss.ssid_len)
902 goto mgmt_out; /* not ready to merge yet */
903
904 switch (fc & IEEE80211_FCTL_STYPE) {
905 case IEEE80211_STYPE_PROBE_REQ:
906 ieee80211_rx_mgmt_probe_req(sdata, skb);
907 break;
908 case IEEE80211_STYPE_PROBE_RESP:
909 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
910 rx_status);
911 break;
912 case IEEE80211_STYPE_BEACON:
913 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
914 rx_status);
915 break;
916 case IEEE80211_STYPE_AUTH:
917 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
918 break;
919 }
920
921 mgmt_out:
922 mutex_unlock(&sdata->u.ibss.mtx);
923 }
924
925 void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
926 {
927 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
928 struct sta_info *sta;
929
930 mutex_lock(&ifibss->mtx);
931
932 /*
933 * Work could be scheduled after scan or similar
934 * when we aren't even joined (or trying) with a
935 * network.
936 */
937 if (!ifibss->ssid_len)
938 goto out;
939
940 spin_lock_bh(&ifibss->incomplete_lock);
941 while (!list_empty(&ifibss->incomplete_stations)) {
942 sta = list_first_entry(&ifibss->incomplete_stations,
943 struct sta_info, list);
944 list_del(&sta->list);
945 spin_unlock_bh(&ifibss->incomplete_lock);
946
947 ieee80211_ibss_finish_sta(sta);
948 rcu_read_unlock();
949 spin_lock_bh(&ifibss->incomplete_lock);
950 }
951 spin_unlock_bh(&ifibss->incomplete_lock);
952
953 switch (ifibss->state) {
954 case IEEE80211_IBSS_MLME_SEARCH:
955 ieee80211_sta_find_ibss(sdata);
956 break;
957 case IEEE80211_IBSS_MLME_JOINED:
958 ieee80211_sta_merge_ibss(sdata);
959 break;
960 default:
961 WARN_ON(1);
962 break;
963 }
964
965 out:
966 mutex_unlock(&ifibss->mtx);
967 }
968
969 static void ieee80211_ibss_timer(unsigned long data)
970 {
971 struct ieee80211_sub_if_data *sdata =
972 (struct ieee80211_sub_if_data *) data;
973 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
974 struct ieee80211_local *local = sdata->local;
975
976 if (local->quiescing) {
977 ifibss->timer_running = true;
978 return;
979 }
980
981 ieee80211_queue_work(&local->hw, &sdata->work);
982 }
983
984 #ifdef CONFIG_PM
985 void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
986 {
987 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
988
989 if (del_timer_sync(&ifibss->timer))
990 ifibss->timer_running = true;
991 }
992
993 void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
994 {
995 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
996
997 if (ifibss->timer_running) {
998 add_timer(&ifibss->timer);
999 ifibss->timer_running = false;
1000 }
1001 }
1002 #endif
1003
1004 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
1005 {
1006 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1007
1008 setup_timer(&ifibss->timer, ieee80211_ibss_timer,
1009 (unsigned long) sdata);
1010 mutex_init(&ifibss->mtx);
1011 INIT_LIST_HEAD(&ifibss->incomplete_stations);
1012 spin_lock_init(&ifibss->incomplete_lock);
1013 }
1014
1015 /* scan finished notification */
1016 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
1017 {
1018 struct ieee80211_sub_if_data *sdata;
1019
1020 mutex_lock(&local->iflist_mtx);
1021 list_for_each_entry(sdata, &local->interfaces, list) {
1022 if (!ieee80211_sdata_running(sdata))
1023 continue;
1024 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
1025 continue;
1026 sdata->u.ibss.last_scan_completed = jiffies;
1027 ieee80211_queue_work(&local->hw, &sdata->work);
1028 }
1029 mutex_unlock(&local->iflist_mtx);
1030 }
1031
1032 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
1033 struct cfg80211_ibss_params *params)
1034 {
1035 struct sk_buff *skb;
1036 u32 changed = 0;
1037
1038 skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
1039 sizeof(struct ieee80211_hdr_3addr) +
1040 12 /* struct ieee80211_mgmt.u.beacon */ +
1041 2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
1042 2 + 8 /* max Supported Rates */ +
1043 3 /* max DS params */ +
1044 4 /* IBSS params */ +
1045 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
1046 2 + sizeof(struct ieee80211_ht_cap) +
1047 2 + sizeof(struct ieee80211_ht_info) +
1048 params->ie_len);
1049 if (!skb)
1050 return -ENOMEM;
1051
1052 mutex_lock(&sdata->u.ibss.mtx);
1053
1054 if (params->bssid) {
1055 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
1056 sdata->u.ibss.fixed_bssid = true;
1057 } else
1058 sdata->u.ibss.fixed_bssid = false;
1059
1060 sdata->u.ibss.privacy = params->privacy;
1061 sdata->u.ibss.basic_rates = params->basic_rates;
1062 memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
1063 sizeof(params->mcast_rate));
1064
1065 sdata->vif.bss_conf.beacon_int = params->beacon_interval;
1066
1067 sdata->u.ibss.channel = params->channel;
1068 sdata->u.ibss.channel_type = params->channel_type;
1069 sdata->u.ibss.fixed_channel = params->channel_fixed;
1070
1071 /* fix ourselves to that channel now already */
1072 if (params->channel_fixed) {
1073 sdata->local->oper_channel = params->channel;
1074 if (!ieee80211_set_channel_type(sdata->local, sdata,
1075 params->channel_type)) {
1076 mutex_unlock(&sdata->u.ibss.mtx);
1077 kfree_skb(skb);
1078 return -EINVAL;
1079 }
1080 }
1081
1082 if (params->ie) {
1083 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
1084 GFP_KERNEL);
1085 if (sdata->u.ibss.ie)
1086 sdata->u.ibss.ie_len = params->ie_len;
1087 }
1088
1089 sdata->u.ibss.skb = skb;
1090 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1091 sdata->u.ibss.ibss_join_req = jiffies;
1092
1093 memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
1094 sdata->u.ibss.ssid_len = params->ssid_len;
1095
1096 mutex_unlock(&sdata->u.ibss.mtx);
1097
1098 mutex_lock(&sdata->local->mtx);
1099 ieee80211_recalc_idle(sdata->local);
1100 mutex_unlock(&sdata->local->mtx);
1101
1102 /*
1103 * 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
1104 * reserved, but an HT STA shall protect HT transmissions as though
1105 * the HT Protection field were set to non-HT mixed mode.
1106 *
1107 * In an IBSS, the RIFS Mode field of the HT Operation element is
1108 * also reserved, but an HT STA shall operate as though this field
1109 * were set to 1.
1110 */
1111
1112 sdata->vif.bss_conf.ht_operation_mode |=
1113 IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
1114 | IEEE80211_HT_PARAM_RIFS_MODE;
1115
1116 changed |= BSS_CHANGED_HT;
1117 ieee80211_bss_info_change_notify(sdata, changed);
1118
1119 ieee80211_queue_work(&sdata->local->hw, &sdata->work);
1120
1121 return 0;
1122 }
1123
1124 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
1125 {
1126 struct sk_buff *skb;
1127 struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
1128 struct ieee80211_local *local = sdata->local;
1129 struct cfg80211_bss *cbss;
1130 u16 capability;
1131 int active_ibss;
1132 struct sta_info *sta;
1133
1134 mutex_lock(&sdata->u.ibss.mtx);
1135
1136 sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
1137 memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
1138 sdata->u.ibss.ssid_len = 0;
1139
1140 active_ibss = ieee80211_sta_active_ibss(sdata);
1141
1142 if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
1143 capability = WLAN_CAPABILITY_IBSS;
1144
1145 if (ifibss->privacy)
1146 capability |= WLAN_CAPABILITY_PRIVACY;
1147
1148 cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
1149 ifibss->bssid, ifibss->ssid,
1150 ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
1151 WLAN_CAPABILITY_PRIVACY,
1152 capability);
1153
1154 if (cbss) {
1155 cfg80211_unlink_bss(local->hw.wiphy, cbss);
1156 cfg80211_put_bss(cbss);
1157 }
1158 }
1159
1160 sta_info_flush(sdata->local, sdata);
1161
1162 spin_lock_bh(&ifibss->incomplete_lock);
1163 while (!list_empty(&ifibss->incomplete_stations)) {
1164 sta = list_first_entry(&ifibss->incomplete_stations,
1165 struct sta_info, list);
1166 list_del(&sta->list);
1167 spin_unlock_bh(&ifibss->incomplete_lock);
1168
1169 sta_info_free(local, sta);
1170 spin_lock_bh(&ifibss->incomplete_lock);
1171 }
1172 spin_unlock_bh(&ifibss->incomplete_lock);
1173
1174 netif_carrier_off(sdata->dev);
1175
1176 /* remove beacon */
1177 kfree(sdata->u.ibss.ie);
1178 skb = rcu_dereference_protected(sdata->u.ibss.presp,
1179 lockdep_is_held(&sdata->u.ibss.mtx));
1180 RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
1181 sdata->vif.bss_conf.ibss_joined = false;
1182 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
1183 BSS_CHANGED_IBSS);
1184 synchronize_rcu();
1185 kfree_skb(skb);
1186
1187 skb_queue_purge(&sdata->skb_queue);
1188
1189 del_timer_sync(&sdata->u.ibss.timer);
1190
1191 mutex_unlock(&sdata->u.ibss.mtx);
1192
1193 mutex_lock(&local->mtx);
1194 ieee80211_recalc_idle(sdata->local);
1195 mutex_unlock(&local->mtx);
1196
1197 return 0;
1198 }
Linux kernel - Deliverables
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