mac80211: split IBSS/managed code
[linux-2.6.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/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 "rate.h"
26
27 #define IEEE80211_SCAN_INTERVAL (2 * HZ)
28 #define IEEE80211_SCAN_INTERVAL_SLOW (15 * 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_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
38                                         struct ieee80211_mgmt *mgmt,
39                                         size_t len)
40 {
41         u16 auth_alg, auth_transaction, status_code;
42
43         if (len < 24 + 6)
44                 return;
45
46         auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
47         auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
48         status_code = le16_to_cpu(mgmt->u.auth.status_code);
49
50         /*
51          * IEEE 802.11 standard does not require authentication in IBSS
52          * networks and most implementations do not seem to use it.
53          * However, try to reply to authentication attempts if someone
54          * has actually implemented this.
55          */
56         if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
57                 ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
58                                     sdata->u.ibss.bssid, 0);
59 }
60
61 static int __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
62                                      const u8 *bssid, const int beacon_int,
63                                      const int freq,
64                                      const size_t supp_rates_len,
65                                      const u8 *supp_rates,
66                                      const u16 capability)
67 {
68         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
69         struct ieee80211_local *local = sdata->local;
70         int res = 0, rates, i, j;
71         struct sk_buff *skb;
72         struct ieee80211_mgmt *mgmt;
73         u8 *pos;
74         struct ieee80211_supported_band *sband;
75         union iwreq_data wrqu;
76
77         if (local->ops->reset_tsf) {
78                 /* Reset own TSF to allow time synchronization work. */
79                 local->ops->reset_tsf(local_to_hw(local));
80         }
81
82         if ((ifibss->flags & IEEE80211_IBSS_PREV_BSSID_SET) &&
83            memcmp(ifibss->bssid, bssid, ETH_ALEN) == 0)
84                 return res;
85
86         skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
87         if (!skb) {
88                 printk(KERN_DEBUG "%s: failed to allocate buffer for probe "
89                        "response\n", sdata->dev->name);
90                 return -ENOMEM;
91         }
92
93         if (!(ifibss->flags & IEEE80211_IBSS_PREV_BSSID_SET)) {
94                 /* Remove possible STA entries from other IBSS networks. */
95                 sta_info_flush_delayed(sdata);
96         }
97
98         memcpy(ifibss->bssid, bssid, ETH_ALEN);
99         res = ieee80211_if_config(sdata, IEEE80211_IFCC_BSSID);
100         if (res)
101                 return res;
102
103         local->hw.conf.beacon_int = beacon_int >= 10 ? beacon_int : 10;
104
105         sdata->drop_unencrypted = capability &
106                 WLAN_CAPABILITY_PRIVACY ? 1 : 0;
107
108         res = ieee80211_set_freq(sdata, freq);
109
110         if (res)
111                 return res;
112
113         sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
114
115         /* Build IBSS probe response */
116
117         skb_reserve(skb, local->hw.extra_tx_headroom);
118
119         mgmt = (struct ieee80211_mgmt *)
120                 skb_put(skb, 24 + sizeof(mgmt->u.beacon));
121         memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
122         mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
123                                           IEEE80211_STYPE_PROBE_RESP);
124         memset(mgmt->da, 0xff, ETH_ALEN);
125         memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
126         memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
127         mgmt->u.beacon.beacon_int =
128                 cpu_to_le16(local->hw.conf.beacon_int);
129         mgmt->u.beacon.capab_info = cpu_to_le16(capability);
130
131         pos = skb_put(skb, 2 + ifibss->ssid_len);
132         *pos++ = WLAN_EID_SSID;
133         *pos++ = ifibss->ssid_len;
134         memcpy(pos, ifibss->ssid, ifibss->ssid_len);
135
136         rates = supp_rates_len;
137         if (rates > 8)
138                 rates = 8;
139         pos = skb_put(skb, 2 + rates);
140         *pos++ = WLAN_EID_SUPP_RATES;
141         *pos++ = rates;
142         memcpy(pos, supp_rates, rates);
143
144         if (sband->band == IEEE80211_BAND_2GHZ) {
145                 pos = skb_put(skb, 2 + 1);
146                 *pos++ = WLAN_EID_DS_PARAMS;
147                 *pos++ = 1;
148                 *pos++ = ieee80211_frequency_to_channel(freq);
149         }
150
151         pos = skb_put(skb, 2 + 2);
152         *pos++ = WLAN_EID_IBSS_PARAMS;
153         *pos++ = 2;
154         /* FIX: set ATIM window based on scan results */
155         *pos++ = 0;
156         *pos++ = 0;
157
158         if (supp_rates_len > 8) {
159                 rates = supp_rates_len - 8;
160                 pos = skb_put(skb, 2 + rates);
161                 *pos++ = WLAN_EID_EXT_SUPP_RATES;
162                 *pos++ = rates;
163                 memcpy(pos, &supp_rates[8], rates);
164         }
165
166         ifibss->probe_resp = skb;
167
168         ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON |
169                                    IEEE80211_IFCC_BEACON_ENABLED);
170
171
172         rates = 0;
173         for (i = 0; i < supp_rates_len; i++) {
174                 int bitrate = (supp_rates[i] & 0x7f) * 5;
175                 for (j = 0; j < sband->n_bitrates; j++)
176                         if (sband->bitrates[j].bitrate == bitrate)
177                                 rates |= BIT(j);
178         }
179
180         ieee80211_sta_def_wmm_params(sdata, supp_rates_len, supp_rates);
181
182         ifibss->flags |= IEEE80211_IBSS_PREV_BSSID_SET;
183         ifibss->state = IEEE80211_IBSS_MLME_JOINED;
184         mod_timer(&ifibss->timer, jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
185
186         memset(&wrqu, 0, sizeof(wrqu));
187         memcpy(wrqu.ap_addr.sa_data, bssid, ETH_ALEN);
188         wireless_send_event(sdata->dev, SIOCGIWAP, &wrqu, NULL);
189
190         return res;
191 }
192
193 static int ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
194                                    struct ieee80211_bss *bss)
195 {
196         return __ieee80211_sta_join_ibss(sdata,
197                                          bss->cbss.bssid,
198                                          bss->cbss.beacon_interval,
199                                          bss->cbss.channel->center_freq,
200                                          bss->supp_rates_len, bss->supp_rates,
201                                          bss->cbss.capability);
202 }
203
204 static void ieee80211_rx_bss_info(struct ieee80211_sub_if_data *sdata,
205                                   struct ieee80211_mgmt *mgmt,
206                                   size_t len,
207                                   struct ieee80211_rx_status *rx_status,
208                                   struct ieee802_11_elems *elems,
209                                   bool beacon)
210 {
211         struct ieee80211_local *local = sdata->local;
212         int freq;
213         struct ieee80211_bss *bss;
214         struct sta_info *sta;
215         struct ieee80211_channel *channel;
216         u64 beacon_timestamp, rx_timestamp;
217         u32 supp_rates = 0;
218         enum ieee80211_band band = rx_status->band;
219
220         if (elems->ds_params && elems->ds_params_len == 1)
221                 freq = ieee80211_channel_to_frequency(elems->ds_params[0]);
222         else
223                 freq = rx_status->freq;
224
225         channel = ieee80211_get_channel(local->hw.wiphy, freq);
226
227         if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
228                 return;
229
230         if (sdata->vif.type == NL80211_IFTYPE_ADHOC && elems->supp_rates &&
231             memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
232                 supp_rates = ieee80211_sta_get_rates(local, elems, band);
233
234                 rcu_read_lock();
235
236                 sta = sta_info_get(local, mgmt->sa);
237                 if (sta) {
238                         u32 prev_rates;
239
240                         prev_rates = sta->sta.supp_rates[band];
241                         /* make sure mandatory rates are always added */
242                         sta->sta.supp_rates[band] = supp_rates |
243                                 ieee80211_mandatory_rates(local, band);
244
245 #ifdef CONFIG_MAC80211_IBSS_DEBUG
246                         if (sta->sta.supp_rates[band] != prev_rates)
247                                 printk(KERN_DEBUG "%s: updated supp_rates set "
248                                     "for %pM based on beacon info (0x%llx | "
249                                     "0x%llx -> 0x%llx)\n",
250                                     sdata->dev->name,
251                                     sta->sta.addr,
252                                     (unsigned long long) prev_rates,
253                                     (unsigned long long) supp_rates,
254                                     (unsigned long long) sta->sta.supp_rates[band]);
255 #endif
256                 } else
257                         ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
258
259                 rcu_read_unlock();
260         }
261
262         bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
263                                         channel, beacon);
264         if (!bss)
265                 return;
266
267         /* was just updated in ieee80211_bss_info_update */
268         beacon_timestamp = bss->cbss.tsf;
269
270         /* check if we need to merge IBSS */
271
272         /* merge only on beacons (???) */
273         if (!beacon)
274                 goto put_bss;
275
276         /* we use a fixed BSSID */
277         if (sdata->u.ibss.flags & IEEE80211_IBSS_BSSID_SET)
278                 goto put_bss;
279
280         /* not an IBSS */
281         if (!(bss->cbss.capability & WLAN_CAPABILITY_IBSS))
282                 goto put_bss;
283
284         /* different channel */
285         if (bss->cbss.channel != local->oper_channel)
286                 goto put_bss;
287
288         /* different SSID */
289         if (elems->ssid_len != sdata->u.ibss.ssid_len ||
290             memcmp(elems->ssid, sdata->u.ibss.ssid,
291                                 sdata->u.ibss.ssid_len))
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 if (local && local->ops && local->ops->get_tsf)
319                 /* second best option: get current TSF */
320                 rx_timestamp = local->ops->get_tsf(local_to_hw(local));
321         else
322                 /* can't merge without knowing the TSF */
323                 rx_timestamp = -1LLU;
324
325 #ifdef CONFIG_MAC80211_IBSS_DEBUG
326         printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
327                "%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
328                mgmt->sa, mgmt->bssid,
329                (unsigned long long)rx_timestamp,
330                (unsigned long long)beacon_timestamp,
331                (unsigned long long)(rx_timestamp - beacon_timestamp),
332                jiffies);
333 #endif
334
335         if (beacon_timestamp > rx_timestamp) {
336 #ifdef CONFIG_MAC80211_IBSS_DEBUG
337                 printk(KERN_DEBUG "%s: beacon TSF higher than "
338                        "local TSF - IBSS merge with BSSID %pM\n",
339                        sdata->dev->name, mgmt->bssid);
340 #endif
341                 ieee80211_sta_join_ibss(sdata, bss);
342                 ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates);
343         }
344
345  put_bss:
346         ieee80211_rx_bss_put(local, bss);
347 }
348
349 /*
350  * Add a new IBSS station, will also be called by the RX code when,
351  * in IBSS mode, receiving a frame from a yet-unknown station, hence
352  * must be callable in atomic context.
353  */
354 struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
355                                         u8 *bssid,u8 *addr, u32 supp_rates)
356 {
357         struct ieee80211_local *local = sdata->local;
358         struct sta_info *sta;
359         int band = local->hw.conf.channel->band;
360
361         /* TODO: Could consider removing the least recently used entry and
362          * allow new one to be added. */
363         if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
364                 if (net_ratelimit()) {
365                         printk(KERN_DEBUG "%s: No room for a new IBSS STA "
366                                "entry %pM\n", sdata->dev->name, addr);
367                 }
368                 return NULL;
369         }
370
371         if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
372                 return NULL;
373
374 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
375         printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n",
376                wiphy_name(local->hw.wiphy), addr, sdata->dev->name);
377 #endif
378
379         sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
380         if (!sta)
381                 return NULL;
382
383         set_sta_flags(sta, WLAN_STA_AUTHORIZED);
384
385         /* make sure mandatory rates are always added */
386         sta->sta.supp_rates[band] = supp_rates |
387                         ieee80211_mandatory_rates(local, band);
388
389         rate_control_rate_init(sta);
390
391         if (sta_info_insert(sta))
392                 return NULL;
393
394         return sta;
395 }
396
397 static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
398 {
399         struct ieee80211_local *local = sdata->local;
400         int active = 0;
401         struct sta_info *sta;
402
403         rcu_read_lock();
404
405         list_for_each_entry_rcu(sta, &local->sta_list, list) {
406                 if (sta->sdata == sdata &&
407                     time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
408                                jiffies)) {
409                         active++;
410                         break;
411                 }
412         }
413
414         rcu_read_unlock();
415
416         return active;
417 }
418
419
420 static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
421 {
422         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
423
424         mod_timer(&ifibss->timer, jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
425
426         ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
427         if (ieee80211_sta_active_ibss(sdata))
428                 return;
429
430         if ((ifibss->flags & IEEE80211_IBSS_BSSID_SET) &&
431             (!(ifibss->flags & IEEE80211_IBSS_AUTO_CHANNEL_SEL)))
432                 return;
433
434         printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
435                "IBSS networks with same SSID (merge)\n", sdata->dev->name);
436
437         /* XXX maybe racy? */
438         if (sdata->local->scan_req)
439                 return;
440
441         memcpy(sdata->local->int_scan_req.ssids[0].ssid,
442                ifibss->ssid, IEEE80211_MAX_SSID_LEN);
443         sdata->local->int_scan_req.ssids[0].ssid_len = ifibss->ssid_len;
444         ieee80211_request_scan(sdata, &sdata->local->int_scan_req);
445 }
446
447 static int 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->flags & IEEE80211_IBSS_BSSID_SET) {
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[local->hw.conf.channel->band];
475
476         if (local->hw.conf.beacon_int == 0)
477                 local->hw.conf.beacon_int = 100;
478
479         capability = WLAN_CAPABILITY_IBSS;
480
481         if (sdata->default_key)
482                 capability |= WLAN_CAPABILITY_PRIVACY;
483         else
484                 sdata->drop_unencrypted = 0;
485
486         pos = supp_rates;
487         for (i = 0; i < sband->n_bitrates; i++) {
488                 int rate = sband->bitrates[i].bitrate;
489                 *pos++ = (u8) (rate / 5);
490         }
491
492         return __ieee80211_sta_join_ibss(sdata,
493                                          bssid, local->hw.conf.beacon_int,
494                                          local->hw.conf.channel->center_freq,
495                                          sband->n_bitrates, supp_rates,
496                                          capability);
497 }
498
499 static int ieee80211_sta_find_ibss(struct ieee80211_sub_if_data *sdata)
500 {
501         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
502         struct ieee80211_local *local = sdata->local;
503         struct ieee80211_bss *bss;
504         const u8 *bssid = NULL;
505         int active_ibss;
506
507         if (ifibss->ssid_len == 0)
508                 return -EINVAL;
509
510         active_ibss = ieee80211_sta_active_ibss(sdata);
511 #ifdef CONFIG_MAC80211_IBSS_DEBUG
512         printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
513                sdata->dev->name, active_ibss);
514 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
515
516         if (active_ibss)
517                 return 0;
518
519         if (ifibss->flags & IEEE80211_IBSS_BSSID_SET)
520                 bssid = ifibss->bssid;
521         bss = (void *)cfg80211_get_bss(local->hw.wiphy, NULL, bssid,
522                                        ifibss->ssid, ifibss->ssid_len,
523                                        WLAN_CAPABILITY_IBSS,
524                                        WLAN_CAPABILITY_IBSS);
525
526 #ifdef CONFIG_MAC80211_IBSS_DEBUG
527         if (bss)
528                 printk(KERN_DEBUG "   sta_find_ibss: selected %pM current "
529                        "%pM\n", bss->cbss.bssid, ifibss->bssid);
530 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
531
532         if (bss &&
533             (!(ifibss->flags & IEEE80211_IBSS_PREV_BSSID_SET) ||
534              memcmp(ifibss->bssid, bss->cbss.bssid, ETH_ALEN))) {
535                 int ret;
536
537                 printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
538                        " based on configured SSID\n",
539                        sdata->dev->name, bss->cbss.bssid);
540
541                 ret = ieee80211_sta_join_ibss(sdata, bss);
542                 ieee80211_rx_bss_put(local, bss);
543                 return ret;
544         } else if (bss)
545                 ieee80211_rx_bss_put(local, bss);
546
547 #ifdef CONFIG_MAC80211_IBSS_DEBUG
548         printk(KERN_DEBUG "   did not try to join ibss\n");
549 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
550
551         /* Selected IBSS not found in current scan results - try to scan */
552         if (ifibss->state == IEEE80211_IBSS_MLME_JOINED &&
553             !ieee80211_sta_active_ibss(sdata)) {
554                 mod_timer(&ifibss->timer, jiffies +
555                                           IEEE80211_IBSS_MERGE_INTERVAL);
556         } else if (time_after(jiffies, local->last_scan_completed +
557                                         IEEE80211_SCAN_INTERVAL)) {
558                 printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
559                        "join\n", sdata->dev->name);
560
561                 /* XXX maybe racy? */
562                 if (local->scan_req)
563                         return -EBUSY;
564
565                 memcpy(local->int_scan_req.ssids[0].ssid,
566                        ifibss->ssid, IEEE80211_MAX_SSID_LEN);
567                 local->int_scan_req.ssids[0].ssid_len = ifibss->ssid_len;
568                 return ieee80211_request_scan(sdata, &local->int_scan_req);
569         } else if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) {
570                 int interval = IEEE80211_SCAN_INTERVAL;
571
572                 if (time_after(jiffies, ifibss->ibss_join_req +
573                                IEEE80211_IBSS_JOIN_TIMEOUT)) {
574                         if (!(local->oper_channel->flags &
575                                                 IEEE80211_CHAN_NO_IBSS))
576                                 return ieee80211_sta_create_ibss(sdata);
577                         printk(KERN_DEBUG "%s: IBSS not allowed on"
578                                " %d MHz\n", sdata->dev->name,
579                                local->hw.conf.channel->center_freq);
580
581                         /* No IBSS found - decrease scan interval and continue
582                          * scanning. */
583                         interval = IEEE80211_SCAN_INTERVAL_SLOW;
584                 }
585
586                 ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
587                 mod_timer(&ifibss->timer, jiffies + interval);
588                 return 0;
589         }
590
591         return 0;
592 }
593
594 static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
595                                         struct ieee80211_mgmt *mgmt,
596                                         size_t len)
597 {
598         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
599         struct ieee80211_local *local = sdata->local;
600         int tx_last_beacon;
601         struct sk_buff *skb;
602         struct ieee80211_mgmt *resp;
603         u8 *pos, *end;
604
605         if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
606             len < 24 + 2 || !ifibss->probe_resp)
607                 return;
608
609         if (local->ops->tx_last_beacon)
610                 tx_last_beacon = local->ops->tx_last_beacon(local_to_hw(local));
611         else
612                 tx_last_beacon = 1;
613
614 #ifdef CONFIG_MAC80211_IBSS_DEBUG
615         printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
616                " (tx_last_beacon=%d)\n",
617                sdata->dev->name, mgmt->sa, mgmt->da,
618                mgmt->bssid, tx_last_beacon);
619 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
620
621         if (!tx_last_beacon)
622                 return;
623
624         if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
625             memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
626                 return;
627
628         end = ((u8 *) mgmt) + len;
629         pos = mgmt->u.probe_req.variable;
630         if (pos[0] != WLAN_EID_SSID ||
631             pos + 2 + pos[1] > end) {
632 #ifdef CONFIG_MAC80211_IBSS_DEBUG
633                 printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
634                        "from %pM\n",
635                        sdata->dev->name, mgmt->sa);
636 #endif
637                 return;
638         }
639         if (pos[1] != 0 &&
640             (pos[1] != ifibss->ssid_len ||
641              memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len) != 0)) {
642                 /* Ignore ProbeReq for foreign SSID */
643                 return;
644         }
645
646         /* Reply with ProbeResp */
647         skb = skb_copy(ifibss->probe_resp, GFP_KERNEL);
648         if (!skb)
649                 return;
650
651         resp = (struct ieee80211_mgmt *) skb->data;
652         memcpy(resp->da, mgmt->sa, ETH_ALEN);
653 #ifdef CONFIG_MAC80211_IBSS_DEBUG
654         printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
655                sdata->dev->name, resp->da);
656 #endif /* CONFIG_MAC80211_IBSS_DEBUG */
657         ieee80211_tx_skb(sdata, skb, 0);
658 }
659
660 static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
661                                          struct ieee80211_mgmt *mgmt,
662                                          size_t len,
663                                          struct ieee80211_rx_status *rx_status)
664 {
665         size_t baselen;
666         struct ieee802_11_elems elems;
667
668         if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN))
669                 return; /* ignore ProbeResp to foreign address */
670
671         baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
672         if (baselen > len)
673                 return;
674
675         ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
676                                 &elems);
677
678         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
679 }
680
681 static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
682                                      struct ieee80211_mgmt *mgmt,
683                                      size_t len,
684                                      struct ieee80211_rx_status *rx_status)
685 {
686         size_t baselen;
687         struct ieee802_11_elems elems;
688
689         /* Process beacon from the current BSS */
690         baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
691         if (baselen > len)
692                 return;
693
694         ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
695
696         ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
697 }
698
699 static void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
700                                           struct sk_buff *skb)
701 {
702         struct ieee80211_rx_status *rx_status;
703         struct ieee80211_mgmt *mgmt;
704         u16 fc;
705
706         rx_status = (struct ieee80211_rx_status *) skb->cb;
707         mgmt = (struct ieee80211_mgmt *) skb->data;
708         fc = le16_to_cpu(mgmt->frame_control);
709
710         switch (fc & IEEE80211_FCTL_STYPE) {
711         case IEEE80211_STYPE_PROBE_REQ:
712                 ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len);
713                 break;
714         case IEEE80211_STYPE_PROBE_RESP:
715                 ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
716                                              rx_status);
717                 break;
718         case IEEE80211_STYPE_BEACON:
719                 ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
720                                          rx_status);
721                 break;
722         case IEEE80211_STYPE_AUTH:
723                 ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
724                 break;
725         }
726
727         kfree_skb(skb);
728 }
729
730 static void ieee80211_ibss_work(struct work_struct *work)
731 {
732         struct ieee80211_sub_if_data *sdata =
733                 container_of(work, struct ieee80211_sub_if_data, u.ibss.work);
734         struct ieee80211_local *local = sdata->local;
735         struct ieee80211_if_ibss *ifibss;
736         struct sk_buff *skb;
737
738         if (!netif_running(sdata->dev))
739                 return;
740
741         if (local->sw_scanning || local->hw_scanning)
742                 return;
743
744         if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC))
745                 return;
746         ifibss = &sdata->u.ibss;
747
748         while ((skb = skb_dequeue(&ifibss->skb_queue)))
749                 ieee80211_ibss_rx_queued_mgmt(sdata, skb);
750
751         if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request))
752                 return;
753
754         switch (ifibss->state) {
755         case IEEE80211_IBSS_MLME_SEARCH:
756                 ieee80211_sta_find_ibss(sdata);
757                 break;
758         case IEEE80211_IBSS_MLME_JOINED:
759                 ieee80211_sta_merge_ibss(sdata);
760                 break;
761         default:
762                 WARN_ON(1);
763                 break;
764         }
765 }
766
767 static void ieee80211_ibss_timer(unsigned long data)
768 {
769         struct ieee80211_sub_if_data *sdata =
770                 (struct ieee80211_sub_if_data *) data;
771         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
772         struct ieee80211_local *local = sdata->local;
773
774         set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request);
775         queue_work(local->hw.workqueue, &ifibss->work);
776 }
777
778 void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
779 {
780         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
781
782         INIT_WORK(&ifibss->work, ieee80211_ibss_work);
783         setup_timer(&ifibss->timer, ieee80211_ibss_timer,
784                     (unsigned long) sdata);
785         skb_queue_head_init(&ifibss->skb_queue);
786
787         ifibss->flags |= IEEE80211_IBSS_AUTO_BSSID_SEL |
788                         IEEE80211_IBSS_AUTO_CHANNEL_SEL;
789 }
790
791 int ieee80211_ibss_set_ssid(struct ieee80211_sub_if_data *sdata, char *ssid, size_t len)
792 {
793         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
794
795         if (len > IEEE80211_MAX_SSID_LEN)
796                 return -EINVAL;
797
798         if (ifibss->ssid_len != len || memcmp(ifibss->ssid, ssid, len) != 0) {
799                 memset(ifibss->ssid, 0, sizeof(ifibss->ssid));
800                 memcpy(ifibss->ssid, ssid, len);
801                 ifibss->ssid_len = len;
802         }
803
804         ifibss->flags &= ~IEEE80211_IBSS_PREV_BSSID_SET;
805
806         if (len)
807                 ifibss->flags |= IEEE80211_IBSS_SSID_SET;
808         else
809                 ifibss->flags &= ~IEEE80211_IBSS_SSID_SET;
810
811         ifibss->ibss_join_req = jiffies;
812         ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
813         return ieee80211_sta_find_ibss(sdata);
814 }
815
816 int ieee80211_ibss_get_ssid(struct ieee80211_sub_if_data *sdata, char *ssid, size_t *len)
817 {
818         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
819
820         memcpy(ssid, ifibss->ssid, ifibss->ssid_len);
821         *len = ifibss->ssid_len;
822
823         return 0;
824 }
825
826 int ieee80211_ibss_set_bssid(struct ieee80211_sub_if_data *sdata, u8 *bssid)
827 {
828         struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
829
830         if (is_valid_ether_addr(bssid)) {
831                 memcpy(ifibss->bssid, bssid, ETH_ALEN);
832                 ifibss->flags |= IEEE80211_IBSS_BSSID_SET;
833         } else {
834                 memset(ifibss->bssid, 0, ETH_ALEN);
835                 ifibss->flags &= ~IEEE80211_IBSS_BSSID_SET;
836         }
837
838         if (netif_running(sdata->dev)) {
839                 if (ieee80211_if_config(sdata, IEEE80211_IFCC_BSSID)) {
840                         printk(KERN_DEBUG "%s: Failed to config new BSSID to "
841                                "the low-level driver\n", sdata->dev->name);
842                 }
843         }
844
845         return ieee80211_ibss_set_ssid(sdata, ifibss->ssid, ifibss->ssid_len);
846 }
847
848 /* scan finished notification */
849 void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
850 {
851         struct ieee80211_sub_if_data *sdata = local->scan_sdata;
852         struct ieee80211_if_ibss *ifibss;
853
854         if (sdata && sdata->vif.type == NL80211_IFTYPE_ADHOC) {
855                 ifibss = &sdata->u.ibss;
856                 if ((!(ifibss->flags & IEEE80211_IBSS_PREV_BSSID_SET)) ||
857                     !ieee80211_sta_active_ibss(sdata))
858                         ieee80211_sta_find_ibss(sdata);
859         }
860 }
861
862 ieee80211_rx_result
863 ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
864                        struct ieee80211_rx_status *rx_status)
865 {
866         struct ieee80211_local *local = sdata->local;
867         struct ieee80211_mgmt *mgmt;
868         u16 fc;
869
870         if (skb->len < 24)
871                 return RX_DROP_MONITOR;
872
873         mgmt = (struct ieee80211_mgmt *) skb->data;
874         fc = le16_to_cpu(mgmt->frame_control);
875
876         switch (fc & IEEE80211_FCTL_STYPE) {
877         case IEEE80211_STYPE_PROBE_RESP:
878         case IEEE80211_STYPE_BEACON:
879                 memcpy(skb->cb, rx_status, sizeof(*rx_status));
880         case IEEE80211_STYPE_PROBE_REQ:
881         case IEEE80211_STYPE_AUTH:
882                 skb_queue_tail(&sdata->u.ibss.skb_queue, skb);
883                 queue_work(local->hw.workqueue, &sdata->u.ibss.work);
884                 return RX_QUEUED;
885         }
886
887         return RX_DROP_MONITOR;
888 }