mac80211: don't connect to IBSS network with different privacy
[linux-2.6] / 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/if_ether.h>
17 #include <linux/skbuff.h>
18 #include <linux/if_arp.h>
19 #include <linux/etherdevice.h>
20 #include <linux/rtnetlink.h>
21 #include <net/mac80211.h>
22 #include <asm/unaligned.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_SCAN_INTERVAL_SLOW (15 * HZ)
30 #define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
31
32 #define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
33 #define IEEE80211_IBSS_MERGE_DELAY 0x400000
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, status_code;
44
45         if (len < 24 + 6)
46                 return;
47
48         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
49         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
50         status_code = le16_to_cpu(mgmt->u.auth.status_code);
51
52         /*
53          * IEEE 802.11 standard does not require authentication in IBSS
54          * networks and most implementations do not seem to use it.
55          * However, try to reply to authentication attempts if someone
56          * has actually implemented this.
57          */
58         if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
59                 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
60                                     sdata->u.ibss.bssid, 0);
61 }
62
63 static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
64                                       const u8 *bssid, const int beacon_int,
65                                       struct ieee80211_channel *chan,
66                                       const size_t supp_rates_len,
67                                       const u8 *supp_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, j;
73         struct sk_buff *skb;
74         struct ieee80211_mgmt *mgmt;
75         u8 *pos;
76         struct ieee80211_supported_band *sband;
77         u32 bss_change;
78
79
80         /* Reset own TSF to allow time synchronization work. */
81         drv_reset_tsf(local);
82
83         skb = ifibss->skb;
84         rcu_assign_pointer(ifibss->presp, NULL);
85         synchronize_rcu();
86         skb->data = skb->head;
87         skb->len = 0;
88         skb_reset_tail_pointer(skb);
89         skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
90
91         if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
92                 sta_info_flush(sdata->local, sdata);
93
94         memcpy(ifibss->bssid, bssid, ETH_ALEN);
95
96         sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
97
98         local->oper_channel = chan;
99         local->oper_channel_type = NL80211_CHAN_NO_HT;
100         ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
101
102         sband = local->hw.wiphy->bands[chan->band];
103
104         /* Build IBSS probe response */
105         mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
106         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
107         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
108                                           IEEE80211_STYPE_PROBE_RESP);
109         memset(mgmt->da, 0xff, ETH_ALEN);
110         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
111         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
112         mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
113         mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
114         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
115
116         pos = skb_put(skb, 2 + ifibss->ssid_len);
117         *pos++ = WLAN_EID_SSID;
118         *pos++ = ifibss->ssid_len;
119         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
120
121         rates = supp_rates_len;
122         if (rates > 8)
123                 rates = 8;
124         pos = skb_put(skb, 2 + rates);
125         *pos++ = WLAN_EID_SUPP_RATES;
126         *pos++ = rates;
127         memcpy(pos, supp_rates, rates);
128
129         if (sband->band == IEEE80211_BAND_2GHZ) {
130                 pos = skb_put(skb, 2 + 1);
131                 *pos++ = WLAN_EID_DS_PARAMS;
132                 *pos++ = 1;
133                 *pos++ = ieee80211_frequency_to_channel(chan->center_freq);
134         }
135
136         pos = skb_put(skb, 2 + 2);
137         *pos++ = WLAN_EID_IBSS_PARAMS;
138         *pos++ = 2;
139         /* FIX: set ATIM window based on scan results */
140         *pos++ = 0;
141         *pos++ = 0;
142
143         if (supp_rates_len > 8) {
144                 rates = supp_rates_len - 8;
145                 pos = skb_put(skb, 2 + rates);
146                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
147                 *pos++ = rates;
148                 memcpy(pos, &supp_rates[8], rates);
149         }
150
151         if (ifibss->ie_len)
152                 memcpy(skb_put(skb, ifibss->ie_len),
153                        ifibss->ie, ifibss->ie_len);
154
155         rcu_assign_pointer(ifibss->presp, skb);
156
157         sdata->vif.bss_conf.beacon_int = beacon_int;
158         bss_change = BSS_CHANGED_BEACON_INT;
159         bss_change |= ieee80211_reset_erp_info(sdata);
160         bss_change |= BSS_CHANGED_BSSID;
161         bss_change |= BSS_CHANGED_BEACON;
162         bss_change |= BSS_CHANGED_BEACON_ENABLED;
163         ieee80211_bss_info_change_notify(sdata, bss_change);
164
165         rates = 0;
166         for (i = 0; i < supp_rates_len; i++) {
167                 int bitrate = (supp_rates[i] & 0x7f) * 5;
168                 for (j = 0; j < sband->n_bitrates; j++)
169                         if (sband->bitrates[j].bitrate == bitrate)
170                                 rates |= BIT(j);
171         }
172
173         ieee80211_sta_def_wmm_params(sdata, supp_rates_len, supp_rates);
174
175         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
176         mod_timer(&ifibss->timer,
177                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
178
179         cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
180                                   mgmt, skb->len, 0, GFP_KERNEL);
181         cfg80211_ibss_joined(sdata->dev, ifibss->bssid, GFP_KERNEL);
182 }
183
184 static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
185                                     struct ieee80211_bss *bss)
186 {
187         u16 beacon_int = bss->cbss.beacon_interval;
188
189         if (beacon_int < 10)
190                 beacon_int = 10;
191
192         __ieee80211_sta_join_ibss(sdata, bss->cbss.bssid,
193                                   beacon_int,
194                                   bss->cbss.channel,
195                                   bss->supp_rates_len, bss->supp_rates,
196                                   bss->cbss.capability,
197                                   bss->cbss.tsf);
198 }
199
200 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
201                                   struct ieee80211_mgmt *mgmt,
202                                   size_t len,
203                                   struct ieee80211_rx_status *rx_status,
204                                   struct ieee802_11_elems *elems,
205                                   bool beacon)
206 {
207         struct ieee80211_local *local = sdata->local;
208         int freq;
209         struct ieee80211_bss *bss;
210         struct sta_info *sta;
211         struct ieee80211_channel *channel;
212         u64 beacon_timestamp, rx_timestamp;
213         u32 supp_rates = 0;
214         enum ieee80211_band band = rx_status->band;
215
216         if (elems->ds_params && elems->ds_params_len == 1)
217                 freq = ieee80211_channel_to_frequency(elems->ds_params[0]);
218         else
219                 freq = rx_status->freq;
220
221         channel = ieee80211_get_channel(local->hw.wiphy, freq);
222
223         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
224                 return;
225
226         if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates &&
227             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
228                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
229
230                 rcu_read_lock();
231
232                 sta = sta_info_get(local, mgmt->sa);
233                 if (sta) {
234                         u32 prev_rates;
235
236                         prev_rates = sta->sta.supp_rates[band];
237                         /* make sure mandatory rates are always added */
238                         sta->sta.supp_rates[band] = supp_rates |
239                                 ieee80211_mandatory_rates(local, band);
240
241 #ifdef CONFIG_MAC80211_IBSS_DEBUG
242                         if (sta->sta.supp_rates[band] != prev_rates)
243                                 printk(KERN_DEBUG "%s: updated supp_rates set "
244                                     "for %pM based on beacon info (0x%llx | "
245                                     "0x%llx -> 0x%llx)\n",
246                                     sdata->dev->name,
247                                     sta->sta.addr,
248                                     (unsigned long long) prev_rates,
249                                     (unsigned long long) supp_rates,
250                                     (unsigned long long) sta->sta.supp_rates[band]);
251 #endif
252                 } else
253                         ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
254
255                 rcu_read_unlock();
256         }
257
258         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
259                                         channel, beacon);
260         if (!bss)
261                 return;
262
263         /* was just updated in ieee80211_bss_info_update */
264         beacon_timestamp = bss->cbss.tsf;
265
266         /* check if we need to merge IBSS */
267
268         /* merge only on beacons (???) */
269         if (!beacon)
270                 goto put_bss;
271
272         /* we use a fixed BSSID */
273         if (sdata->u.ibss.bssid)
274                 goto put_bss;
275
276         /* not an IBSS */
277         if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS))
278                 goto put_bss;
279
280         /* different channel */
281         if (bss->cbss.channel != local->oper_channel)
282                 goto put_bss;
283
284         /* different SSID */
285         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
286             memcmp(elems->ssid, sdata->u.ibss.ssid,
287                                 sdata->u.ibss.ssid_len))
288                 goto put_bss;
289
290         /* same BSSID */
291         if (memcmp(bss->cbss.bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
292                 goto put_bss;
293
294         if (rx_status->flag & RX_FLAG_TSFT) {
295                 /*
296                  * For correct IBSS merging we need mactime; since mactime is
297                  * defined as the time the first data symbol of the frame hits
298                  * the PHY, and the timestamp of the beacon is defined as "the
299                  * time that the data symbol containing the first bit of the
300                  * timestamp is transmitted to the PHY plus the transmitting
301                  * STA's delays through its local PHY from the MAC-PHY
302                  * interface to its interface with the WM" (802.11 11.1.2)
303                  * - equals the time this bit arrives at the receiver - we have
304                  * to take into account the offset between the two.
305                  *
306                  * E.g. at 1 MBit that means mactime is 192 usec earlier
307                  * (=24 bytes * 8 usecs/byte) than the beacon timestamp.
308                  */
309                 int rate;
310
311                 if (rx_status->flag & RX_FLAG_HT)
312                         rate = 65; /* TODO: HT rates */
313                 else
314                         rate = local->hw.wiphy->bands[band]->
315                                 bitrates[rx_status->rate_idx].bitrate;
316
317                 rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
318         } else {
319                 /*
320                  * second best option: get current TSF
321                  * (will return -1 if not supported)
322                  */
323                 rx_timestamp = drv_get_tsf(local);
324         }
325
326 #ifdef CONFIG_MAC80211_IBSS_DEBUG
327         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
328                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
329                mgmt->sa, mgmt->bssid,
330                (unsigned long long)rx_timestamp,
331                (unsigned long long)beacon_timestamp,
332                (unsigned long long)(rx_timestamp - beacon_timestamp),
333                jiffies);
334 #endif
335
336         /* give slow hardware some time to do the TSF sync */
337         if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY)
338                 goto put_bss;
339
340         if (beacon_timestamp > rx_timestamp) {
341 #ifdef CONFIG_MAC80211_IBSS_DEBUG
342                 printk(KERN_DEBUG "%s: beacon TSF higher than "
343                        "local TSF - IBSS merge with BSSID %pM\n",
344                        sdata->dev->name, mgmt->bssid);
345 #endif
346                 ieee80211_sta_join_ibss(sdata, bss);
347                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
348         }
349
350  put_bss:
351         ieee80211_rx_bss_put(local, bss);
352 }
353
354 /*
355  * Add a new IBSS station, will also be called by the RX code when,
356  * in IBSS mode, receiving a frame from a yet-unknown station, hence
357  * must be callable in atomic context.
358  */
359 struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
360                                         u8 *bssid,u8 *addr, u32 supp_rates)
361 {
362         struct ieee80211_local *local = sdata->local;
363         struct sta_info *sta;
364         int band = local->hw.conf.channel->band;
365
366         /*
367          * XXX: Consider removing the least recently used entry and
368          *      allow new one to be added.
369          */
370         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
371                 if (net_ratelimit())
372                         printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
373                                sdata->dev->name, addr);
374                 return NULL;
375         }
376
377         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
378                 return NULL;
379
380 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
381         printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n",
382                wiphy_name(local->hw.wiphy), addr, sdata->dev->name);
383 #endif
384
385         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
386         if (!sta)
387                 return NULL;
388
389         set_sta_flags(sta, WLAN_STA_AUTHORIZED);
390
391         /* make sure mandatory rates are always added */
392         sta->sta.supp_rates[band] = supp_rates |
393                         ieee80211_mandatory_rates(local, band);
394
395         rate_control_rate_init(sta);
396
397         if (sta_info_insert(sta))
398                 return NULL;
399
400         return sta;
401 }
402
403 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
404 {
405         struct ieee80211_local *local = sdata->local;
406         int active = 0;
407         struct sta_info *sta;
408
409         rcu_read_lock();
410
411         list_for_each_entry_rcu(sta, &local->sta_list, list) {
412                 if (sta->sdata == sdata &&
413                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
414                                jiffies)) {
415                         active++;
416                         break;
417                 }
418         }
419
420         rcu_read_unlock();
421
422         return active;
423 }
424
425
426 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
427 {
428         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
429
430         mod_timer(&ifibss->timer,
431                   round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
432
433         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
434
435         if (ieee80211_sta_active_ibss(sdata))
436                 return;
437
438         if (ifibss->fixed_channel)
439                 return;
440
441         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
442                "IBSS networks with same SSID (merge)\n", sdata->dev->name);
443
444         ieee80211_request_internal_scan(sdata, ifibss->ssid, ifibss->ssid_len);
445 }
446
447 static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
448 {
449         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
450         struct ieee80211_local *local = sdata->local;
451         struct ieee80211_supported_band *sband;
452         u8 *pos;
453         u8 bssid[ETH_ALEN];
454         u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
455         u16 capability;
456         int i;
457
458         if (ifibss->fixed_bssid) {
459                 memcpy(bssid, ifibss->bssid, ETH_ALEN);
460         } else {
461                 /* Generate random, not broadcast, locally administered BSSID. Mix in
462                  * own MAC address to make sure that devices that do not have proper
463                  * random number generator get different BSSID. */
464                 get_random_bytes(bssid, ETH_ALEN);
465                 for (i = 0; i < ETH_ALEN; i++)
466                         bssid[i] ^= sdata->dev->dev_addr[i];
467                 bssid[0] &= ~0x01;
468                 bssid[0] |= 0x02;
469         }
470
471         printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
472                sdata->dev->name, bssid);
473
474         sband = local->hw.wiphy->bands[ifibss->channel->band];
475
476         capability = WLAN_CAPABILITY_IBSS;
477
478         if (sdata->default_key)
479                 capability |= WLAN_CAPABILITY_PRIVACY;
480         else
481                 sdata->drop_unencrypted = 0;
482
483         pos = supp_rates;
484         for (i = 0; i < sband->n_bitrates; i++) {
485                 int rate = sband->bitrates[i].bitrate;
486                 *pos++ = (u8) (rate / 5);
487         }
488
489         __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
490                                   ifibss->channel, sband->n_bitrates,
491                                   supp_rates, capability, 0);
492 }
493
494 static void ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
495 {
496         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
497         struct ieee80211_local *local = sdata->local;
498         struct ieee80211_bss *bss;
499         struct ieee80211_channel *chan = NULL;
500         const u8 *bssid = NULL;
501         int active_ibss;
502         u16 capability;
503
504         active_ibss = ieee80211_sta_active_ibss(sdata);
505 #ifdef CONFIG_MAC80211_IBSS_DEBUG
506         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
507                sdata->dev->name, active_ibss);
508 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
509
510         if (active_ibss)
511                 return;
512
513         capability = WLAN_CAPABILITY_IBSS;
514         if (sdata->default_key)
515                 capability |= WLAN_CAPABILITY_PRIVACY;
516
517         if (ifibss->fixed_bssid)
518                 bssid = ifibss->bssid;
519         if (ifibss->fixed_channel)
520                 chan = ifibss->channel;
521         if (!is_zero_ether_addr(ifibss->bssid))
522                 bssid = ifibss->bssid;
523         bss = (void *)cfg80211_get_bss(local->hw.wiphy, chan, bssid,
524                                        ifibss->ssid, ifibss->ssid_len,
525                                        capability,
526                                        WLAN_CAPABILITY_IBSS |
527                                        WLAN_CAPABILITY_PRIVACY);
528
529 #ifdef CONFIG_MAC80211_IBSS_DEBUG
530         if (bss)
531                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
532                        "%pM\n", bss->cbss.bssid, ifibss->bssid);
533 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
534
535         if (bss && memcmp(ifibss->bssid, bss->cbss.bssid, ETH_ALEN)) {
536                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
537                        " based on configured SSID\n",
538                        sdata->dev->name, bss->cbss.bssid);
539
540                 ieee80211_sta_join_ibss(sdata, bss);
541                 ieee80211_rx_bss_put(local, bss);
542                 return;
543         } else if (bss)
544                 ieee80211_rx_bss_put(local, bss);
545
546 #ifdef CONFIG_MAC80211_IBSS_DEBUG
547         printk(KERN_DEBUG "   did not try to join ibss\n");
548 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
549
550         /* Selected IBSS not found in current scan results - try to scan */
551         if (ifibss->state == IEEE80211_IBSS_MLME_JOINED &&
552             !ieee80211_sta_active_ibss(sdata)) {
553                 mod_timer(&ifibss->timer,
554                           round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
555         } else if (time_after(jiffies, ifibss->last_scan_completed +
556                                         IEEE80211_SCAN_INTERVAL)) {
557                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
558                        "join\n", sdata->dev->name);
559
560                 ieee80211_request_internal_scan(sdata, ifibss->ssid,
561                                                 ifibss->ssid_len);
562         } else if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) {
563                 int interval = IEEE80211_SCAN_INTERVAL;
564
565                 if (time_after(jiffies, ifibss->ibss_join_req +
566                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
567                         if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
568                                 ieee80211_sta_create_ibss(sdata);
569                                 return;
570                         }
571                         printk(KERN_DEBUG "%s: IBSS not allowed on"
572                                " %d MHz\n", sdata->dev->name,
573                                local->hw.conf.channel->center_freq);
574
575                         /* No IBSS found - decrease scan interval and continue
576                          * scanning. */
577                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
578                 }
579
580                 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
581                 mod_timer(&ifibss->timer,
582                           round_jiffies(jiffies + interval));
583         }
584 }
585
586 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
587                                         struct ieee80211_mgmt *mgmt,
588                                         size_t len)
589 {
590         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
591         struct ieee80211_local *local = sdata->local;
592         int tx_last_beacon;
593         struct sk_buff *skb;
594         struct ieee80211_mgmt *resp;
595         u8 *pos, *end;
596
597         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
598             len < 24 + 2 || !ifibss->presp)
599                 return;
600
601         tx_last_beacon = drv_tx_last_beacon(local);
602
603 #ifdef CONFIG_MAC80211_IBSS_DEBUG
604         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
605                " (tx_last_beacon=%d)\n",
606                sdata->dev->name, mgmt->sa, mgmt->da,
607                mgmt->bssid, tx_last_beacon);
608 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
609
610         if (!tx_last_beacon)
611                 return;
612
613         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
614             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
615                 return;
616
617         end = ((u8 *) mgmt) + len;
618         pos = mgmt->u.probe_req.variable;
619         if (pos[0] != WLAN_EID_SSID ||
620             pos + 2 + pos[1] > end) {
621 #ifdef CONFIG_MAC80211_IBSS_DEBUG
622                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
623                        "from %pM\n",
624                        sdata->dev->name, mgmt->sa);
625 #endif
626                 return;
627         }
628         if (pos[1] != 0 &&
629             (pos[1] != ifibss->ssid_len ||
630              !memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
631                 /* Ignore ProbeReq for foreign SSID */
632                 return;
633         }
634
635         /* Reply with ProbeResp */
636         skb = skb_copy(ifibss->presp, GFP_KERNEL);
637         if (!skb)
638                 return;
639
640         resp = (struct ieee80211_mgmt *) skb->data;
641         memcpy(resp->da, mgmt->sa, ETH_ALEN);
642 #ifdef CONFIG_MAC80211_IBSS_DEBUG
643         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
644                sdata->dev->name, resp->da);
645 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
646         ieee80211_tx_skb(sdata, skb, 0);
647 }
648
649 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
650                                          struct ieee80211_mgmt *mgmt,
651                                          size_t len,
652                                          struct ieee80211_rx_status *rx_status)
653 {
654         size_t baselen;
655         struct ieee802_11_elems elems;
656
657         if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
658                 return; /* ignore ProbeResp to foreign address */
659
660         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
661         if (baselen > len)
662                 return;
663
664         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
665                                 &elems);
666
667         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
668 }
669
670 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
671                                      struct ieee80211_mgmt *mgmt,
672                                      size_t len,
673                                      struct ieee80211_rx_status *rx_status)
674 {
675         size_t baselen;
676         struct ieee802_11_elems elems;
677
678         /* Process beacon from the current BSS */
679         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
680         if (baselen > len)
681                 return;
682
683         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
684
685         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
686 }
687
688 static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
689                                           struct sk_buff *skb)
690 {
691         struct ieee80211_rx_status *rx_status;
692         struct ieee80211_mgmt *mgmt;
693         u16 fc;
694
695         rx_status = (struct ieee80211_rx_status *) skb->cb;
696         mgmt = (struct ieee80211_mgmt *) skb->data;
697         fc = le16_to_cpu(mgmt->frame_control);
698
699         switch (fc & IEEE80211_FCTL_STYPE) {
700         case IEEE80211_STYPE_PROBE_REQ:
701                 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len);
702                 break;
703         case IEEE80211_STYPE_PROBE_RESP:
704                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
705                                              rx_status);
706                 break;
707         case IEEE80211_STYPE_BEACON:
708                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
709                                          rx_status);
710                 break;
711         case IEEE80211_STYPE_AUTH:
712                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
713                 break;
714         }
715
716         kfree_skb(skb);
717 }
718
719 static void ieee80211_ibss_work(struct work_struct *work)
720 {
721         struct ieee80211_sub_if_data *sdata =
722                 container_of(work, struct ieee80211_sub_if_data, u.ibss.work);
723         struct ieee80211_local *local = sdata->local;
724         struct ieee80211_if_ibss *ifibss;
725         struct sk_buff *skb;
726
727         if (!netif_running(sdata->dev))
728                 return;
729
730         if (local->sw_scanning || local->hw_scanning)
731                 return;
732
733         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC))
734                 return;
735         ifibss = &sdata->u.ibss;
736
737         while ((skb = skb_dequeue(&ifibss->skb_queue)))
738                 ieee80211_ibss_rx_queued_mgmt(sdata, skb);
739
740         if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request))
741                 return;
742
743         switch (ifibss->state) {
744         case IEEE80211_IBSS_MLME_SEARCH:
745                 ieee80211_sta_find_ibss(sdata);
746                 break;
747         case IEEE80211_IBSS_MLME_JOINED:
748                 ieee80211_sta_merge_ibss(sdata);
749                 break;
750         default:
751                 WARN_ON(1);
752                 break;
753         }
754 }
755
756 static void ieee80211_ibss_timer(unsigned long data)
757 {
758         struct ieee80211_sub_if_data *sdata =
759                 (struct ieee80211_sub_if_data *) data;
760         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
761         struct ieee80211_local *local = sdata->local;
762
763         set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request);
764         queue_work(local->hw.workqueue, &ifibss->work);
765 }
766
767 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
768 {
769         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
770
771         INIT_WORK(&ifibss->work, ieee80211_ibss_work);
772         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
773                     (unsigned long) sdata);
774         skb_queue_head_init(&ifibss->skb_queue);
775 }
776
777 /* scan finished notification */
778 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
779 {
780         struct ieee80211_sub_if_data *sdata;
781
782         mutex_lock(&local->iflist_mtx);
783         list_for_each_entry(sdata, &local->interfaces, list) {
784                 if (!netif_running(sdata->dev))
785                         continue;
786                 if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
787                         continue;
788                 if (!sdata->u.ibss.ssid_len)
789                         continue;
790                 sdata->u.ibss.last_scan_completed = jiffies;
791                 ieee80211_sta_find_ibss(sdata);
792         }
793         mutex_unlock(&local->iflist_mtx);
794 }
795
796 ieee80211_rx_result
797 ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
798                        struct ieee80211_rx_status *rx_status)
799 {
800         struct ieee80211_local *local = sdata->local;
801         struct ieee80211_mgmt *mgmt;
802         u16 fc;
803
804         if (skb->len < 24)
805                 return RX_DROP_MONITOR;
806
807         mgmt = (struct ieee80211_mgmt *) skb->data;
808         fc = le16_to_cpu(mgmt->frame_control);
809
810         switch (fc & IEEE80211_FCTL_STYPE) {
811         case IEEE80211_STYPE_PROBE_RESP:
812         case IEEE80211_STYPE_BEACON:
813                 memcpy(skb->cb, rx_status, sizeof(*rx_status));
814         case IEEE80211_STYPE_PROBE_REQ:
815         case IEEE80211_STYPE_AUTH:
816                 skb_queue_tail(&sdata->u.ibss.skb_queue, skb);
817                 queue_work(local->hw.workqueue, &sdata->u.ibss.work);
818                 return RX_QUEUED;
819         }
820
821         return RX_DROP_MONITOR;
822 }
823
824 int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
825                         struct cfg80211_ibss_params *params)
826 {
827         struct sk_buff *skb;
828
829         if (params->bssid) {
830                 memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
831                 sdata->u.ibss.fixed_bssid = true;
832         } else
833                 sdata->u.ibss.fixed_bssid = false;
834
835         sdata->vif.bss_conf.beacon_int = params->beacon_interval;
836
837         sdata->u.ibss.channel = params->channel;
838         sdata->u.ibss.fixed_channel = params->channel_fixed;
839
840         if (params->ie) {
841                 sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
842                                            GFP_KERNEL);
843                 if (sdata->u.ibss.ie)
844                         sdata->u.ibss.ie_len = params->ie_len;
845         }
846
847         skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
848                             36 /* bitrates */ +
849                             34 /* SSID */ +
850                             3  /* DS params */ +
851                             4  /* IBSS params */ +
852                             params->ie_len);
853         if (!skb)
854                 return -ENOMEM;
855
856         sdata->u.ibss.skb = skb;
857         sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
858         sdata->u.ibss.ibss_join_req = jiffies;
859
860         memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
861
862         /*
863          * The ssid_len setting below is used to see whether
864          * we are active, and we need all other settings
865          * before that may get visible.
866          */
867         mb();
868
869         sdata->u.ibss.ssid_len = params->ssid_len;
870
871         ieee80211_recalc_idle(sdata->local);
872
873         set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
874         queue_work(sdata->local->hw.workqueue, &sdata->u.ibss.work);
875
876         return 0;
877 }
878
879 int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
880 {
881         struct sk_buff *skb;
882
883         del_timer_sync(&sdata->u.ibss.timer);
884         clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
885         cancel_work_sync(&sdata->u.ibss.work);
886         clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
887
888         sta_info_flush(sdata->local, sdata);
889
890         /* remove beacon */
891         kfree(sdata->u.ibss.ie);
892         skb = sdata->u.ibss.presp;
893         rcu_assign_pointer(sdata->u.ibss.presp, NULL);
894         ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
895         synchronize_rcu();
896         kfree_skb(skb);
897
898         skb_queue_purge(&sdata->u.ibss.skb_queue);
899         memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
900         sdata->u.ibss.ssid_len = 0;
901
902         ieee80211_recalc_idle(sdata->local);
903
904         return 0;
905 }