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Commit | Line | Data |
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0a51b27e | 1 | /* |
5484e237 JB |
2 | * Scanning implementation |
3 | * | |
0a51b27e JB |
4 | * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> |
5 | * Copyright 2004, Instant802 Networks, Inc. | |
6 | * Copyright 2005, Devicescape Software, Inc. | |
7 | * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> | |
8 | * Copyright 2007, Michael Wu <flamingice@sourmilk.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 | ||
00d3f14c | 15 | /* TODO: figure out how to avoid that the "current BSS" expires */ |
5484e237 | 16 | |
0a51b27e JB |
17 | #include <linux/wireless.h> |
18 | #include <linux/if_arp.h> | |
078e1e60 | 19 | #include <linux/rtnetlink.h> |
0a51b27e JB |
20 | #include <net/mac80211.h> |
21 | #include <net/iw_handler.h> | |
22 | ||
23 | #include "ieee80211_i.h" | |
24487981 | 24 | #include "driver-ops.h" |
5484e237 | 25 | #include "mesh.h" |
0a51b27e JB |
26 | |
27 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
28 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 29 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 30 | |
c2b13452 | 31 | struct ieee80211_bss * |
5484e237 JB |
32 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
33 | u8 *ssid, u8 ssid_len) | |
34 | { | |
00d3f14c JB |
35 | return (void *)cfg80211_get_bss(local->hw.wiphy, |
36 | ieee80211_get_channel(local->hw.wiphy, | |
37 | freq), | |
38 | bssid, ssid, ssid_len, | |
39 | 0, 0); | |
5484e237 JB |
40 | } |
41 | ||
00d3f14c | 42 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 43 | { |
00d3f14c | 44 | struct ieee80211_bss *bss = (void *)cbss; |
5484e237 | 45 | |
5484e237 JB |
46 | kfree(bss_mesh_id(bss)); |
47 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
48 | } |
49 | ||
50 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 51 | struct ieee80211_bss *bss) |
5484e237 | 52 | { |
00d3f14c | 53 | cfg80211_put_bss((struct cfg80211_bss *)bss); |
5484e237 JB |
54 | } |
55 | ||
c2b13452 | 56 | struct ieee80211_bss * |
5484e237 JB |
57 | ieee80211_bss_info_update(struct ieee80211_local *local, |
58 | struct ieee80211_rx_status *rx_status, | |
59 | struct ieee80211_mgmt *mgmt, | |
60 | size_t len, | |
61 | struct ieee802_11_elems *elems, | |
2a519311 JB |
62 | struct ieee80211_channel *channel, |
63 | bool beacon) | |
5484e237 | 64 | { |
c2b13452 | 65 | struct ieee80211_bss *bss; |
00d3f14c | 66 | int clen; |
2a519311 JB |
67 | s32 signal = 0; |
68 | ||
77965c97 | 69 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 70 | signal = rx_status->signal * 100; |
77965c97 | 71 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 72 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 73 | |
00d3f14c | 74 | bss = (void *)cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
77965c97 | 75 | mgmt, len, signal, GFP_ATOMIC); |
5484e237 | 76 | |
00d3f14c JB |
77 | if (!bss) |
78 | return NULL; | |
79 | ||
80 | bss->cbss.free_priv = ieee80211_rx_bss_free; | |
5484e237 JB |
81 | |
82 | /* save the ERP value so that it is available at association time */ | |
83 | if (elems->erp_info && elems->erp_info_len >= 1) { | |
84 | bss->erp_value = elems->erp_info[0]; | |
85 | bss->has_erp_value = 1; | |
86 | } | |
87 | ||
5484e237 JB |
88 | if (elems->tim) { |
89 | struct ieee80211_tim_ie *tim_ie = | |
90 | (struct ieee80211_tim_ie *)elems->tim; | |
91 | bss->dtim_period = tim_ie->dtim_period; | |
92 | } | |
93 | ||
94 | /* set default value for buggy APs */ | |
95 | if (!elems->tim || bss->dtim_period == 0) | |
96 | bss->dtim_period = 1; | |
97 | ||
98 | bss->supp_rates_len = 0; | |
99 | if (elems->supp_rates) { | |
100 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
101 | if (clen > elems->supp_rates_len) | |
102 | clen = elems->supp_rates_len; | |
103 | memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, | |
104 | clen); | |
105 | bss->supp_rates_len += clen; | |
106 | } | |
107 | if (elems->ext_supp_rates) { | |
108 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
109 | if (clen > elems->ext_supp_rates_len) | |
110 | clen = elems->ext_supp_rates_len; | |
111 | memcpy(&bss->supp_rates[bss->supp_rates_len], | |
112 | elems->ext_supp_rates, clen); | |
113 | bss->supp_rates_len += clen; | |
114 | } | |
115 | ||
5484e237 JB |
116 | bss->wmm_used = elems->wmm_param || elems->wmm_info; |
117 | ||
118 | if (!beacon) | |
119 | bss->last_probe_resp = jiffies; | |
120 | ||
5484e237 JB |
121 | return bss; |
122 | } | |
0a51b27e | 123 | |
98c8fccf | 124 | ieee80211_rx_result |
f1d58c25 | 125 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 126 | { |
f1d58c25 | 127 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 128 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 129 | struct ieee80211_bss *bss; |
98c8fccf JB |
130 | u8 *elements; |
131 | struct ieee80211_channel *channel; | |
132 | size_t baselen; | |
133 | int freq; | |
134 | __le16 fc; | |
135 | bool presp, beacon = false; | |
136 | struct ieee802_11_elems elems; | |
137 | ||
138 | if (skb->len < 2) | |
139 | return RX_DROP_UNUSABLE; | |
140 | ||
141 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
142 | fc = mgmt->frame_control; | |
143 | ||
144 | if (ieee80211_is_ctl(fc)) | |
145 | return RX_CONTINUE; | |
146 | ||
147 | if (skb->len < 24) | |
148 | return RX_DROP_MONITOR; | |
149 | ||
150 | presp = ieee80211_is_probe_resp(fc); | |
151 | if (presp) { | |
152 | /* ignore ProbeResp to foreign address */ | |
153 | if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) | |
154 | return RX_DROP_MONITOR; | |
155 | ||
156 | presp = true; | |
157 | elements = mgmt->u.probe_resp.variable; | |
158 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
159 | } else { | |
160 | beacon = ieee80211_is_beacon(fc); | |
161 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
162 | elements = mgmt->u.beacon.variable; | |
163 | } | |
164 | ||
165 | if (!presp && !beacon) | |
166 | return RX_CONTINUE; | |
167 | ||
168 | if (baselen > skb->len) | |
169 | return RX_DROP_MONITOR; | |
170 | ||
171 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
172 | ||
173 | if (elems.ds_params && elems.ds_params_len == 1) | |
174 | freq = ieee80211_channel_to_frequency(elems.ds_params[0]); | |
175 | else | |
176 | freq = rx_status->freq; | |
177 | ||
178 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
179 | ||
180 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
181 | return RX_DROP_MONITOR; | |
182 | ||
183 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
184 | mgmt, skb->len, &elems, | |
2a519311 | 185 | channel, beacon); |
d048e503 JM |
186 | if (bss) |
187 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf JB |
188 | |
189 | dev_kfree_skb(skb); | |
190 | return RX_QUEUED; | |
191 | } | |
192 | ||
9050bdd8 KV |
193 | /* |
194 | * inform AP that we will go to sleep so that it will buffer the frames | |
195 | * while we scan | |
196 | */ | |
197 | static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) | |
198 | { | |
199 | struct ieee80211_local *local = sdata->local; | |
200 | bool ps = false; | |
201 | ||
202 | /* FIXME: what to do when local->pspolling is true? */ | |
203 | ||
204 | del_timer_sync(&local->dynamic_ps_timer); | |
205 | cancel_work_sync(&local->dynamic_ps_enable_work); | |
206 | ||
207 | if (local->hw.conf.flags & IEEE80211_CONF_PS) { | |
208 | ps = true; | |
209 | local->hw.conf.flags &= ~IEEE80211_CONF_PS; | |
210 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
211 | } | |
212 | ||
213 | if (!ps || !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) | |
214 | /* | |
215 | * If power save was enabled, no need to send a nullfunc | |
216 | * frame because AP knows that we are sleeping. But if the | |
217 | * hardware is creating the nullfunc frame for power save | |
218 | * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not | |
219 | * enabled) and power save was enabled, the firmware just | |
220 | * sent a null frame with power save disabled. So we need | |
221 | * to send a new nullfunc frame to inform the AP that we | |
222 | * are again sleeping. | |
223 | */ | |
224 | ieee80211_send_nullfunc(local, sdata, 1); | |
225 | } | |
226 | ||
227 | /* inform AP that we are awake again, unless power save is enabled */ | |
228 | static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) | |
229 | { | |
230 | struct ieee80211_local *local = sdata->local; | |
231 | ||
965bedad | 232 | if (!local->ps_sdata) |
9050bdd8 KV |
233 | ieee80211_send_nullfunc(local, sdata, 0); |
234 | else { | |
235 | /* | |
236 | * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware | |
237 | * will send a nullfunc frame with the powersave bit set | |
238 | * even though the AP already knows that we are sleeping. | |
239 | * This could be avoided by sending a null frame with power | |
240 | * save bit disabled before enabling the power save, but | |
241 | * this doesn't gain anything. | |
242 | * | |
243 | * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need | |
244 | * to send a nullfunc frame because AP already knows that | |
245 | * we are sleeping, let's just enable power save mode in | |
246 | * hardware. | |
247 | */ | |
248 | local->hw.conf.flags |= IEEE80211_CONF_PS; | |
249 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
250 | } | |
251 | } | |
252 | ||
f3b85252 JB |
253 | static void ieee80211_restore_scan_ies(struct ieee80211_local *local) |
254 | { | |
255 | kfree(local->scan_req->ie); | |
256 | local->scan_req->ie = local->orig_ies; | |
257 | local->scan_req->ie_len = local->orig_ies_len; | |
258 | } | |
259 | ||
2a519311 | 260 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) |
0a51b27e JB |
261 | { |
262 | struct ieee80211_local *local = hw_to_local(hw); | |
263 | struct ieee80211_sub_if_data *sdata; | |
f3b85252 | 264 | bool was_hw_scan; |
0a51b27e | 265 | |
f3b85252 | 266 | mutex_lock(&local->scan_mtx); |
5bc75728 | 267 | |
fbe9c429 | 268 | if (WARN_ON(!local->scanning)) { |
f3b85252 | 269 | mutex_unlock(&local->scan_mtx); |
2a519311 | 270 | return; |
f3b85252 | 271 | } |
5bc75728 | 272 | |
f3b85252 JB |
273 | if (WARN_ON(!local->scan_req)) { |
274 | mutex_unlock(&local->scan_mtx); | |
275 | return; | |
de95a54b JB |
276 | } |
277 | ||
fbe9c429 | 278 | if (test_bit(SCAN_HW_SCANNING, &local->scanning)) |
f3b85252 JB |
279 | ieee80211_restore_scan_ies(local); |
280 | ||
2a519311 JB |
281 | if (local->scan_req != &local->int_scan_req) |
282 | cfg80211_scan_done(local->scan_req, aborted); | |
283 | local->scan_req = NULL; | |
284 | ||
fbe9c429 HS |
285 | was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
286 | local->scanning = 0; | |
58905ca5 | 287 | local->scan_channel = NULL; |
f3b85252 JB |
288 | |
289 | /* we only have to protect scan_req and hw/sw scan */ | |
290 | mutex_unlock(&local->scan_mtx); | |
291 | ||
e8975581 | 292 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); |
5cff20e6 JB |
293 | if (was_hw_scan) |
294 | goto done; | |
0a51b27e | 295 | |
3b8d81e0 | 296 | spin_lock_bh(&local->filter_lock); |
0a51b27e | 297 | local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC; |
24487981 JB |
298 | drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC, |
299 | &local->filter_flags, | |
3b8d81e0 JB |
300 | local->mc_count, |
301 | local->mc_list); | |
302 | spin_unlock_bh(&local->filter_lock); | |
0a51b27e | 303 | |
24487981 | 304 | drv_sw_scan_complete(local); |
80e775bf | 305 | |
078e1e60 JB |
306 | mutex_lock(&local->iflist_mtx); |
307 | list_for_each_entry(sdata, &local->interfaces, list) { | |
fb9ddbf0 JB |
308 | if (!netif_running(sdata->dev)) |
309 | continue; | |
310 | ||
0a51b27e | 311 | /* Tell AP we're back */ |
05c914fe | 312 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
77fdaa12 | 313 | if (sdata->u.mgd.associated) { |
9050bdd8 | 314 | ieee80211_scan_ps_disable(sdata); |
0a51b27e JB |
315 | netif_tx_wake_all_queues(sdata->dev); |
316 | } | |
317 | } else | |
318 | netif_tx_wake_all_queues(sdata->dev); | |
078e1e60 | 319 | |
14b80724 JB |
320 | /* re-enable beaconing */ |
321 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
322 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
323 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
324 | ieee80211_bss_info_change_notify( |
325 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
0a51b27e | 326 | } |
078e1e60 | 327 | mutex_unlock(&local->iflist_mtx); |
0a51b27e JB |
328 | |
329 | done: | |
5cff20e6 | 330 | ieee80211_recalc_idle(local); |
0a51b27e | 331 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 332 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 333 | ieee80211_mesh_notify_scan_completed(local); |
0a51b27e JB |
334 | } |
335 | EXPORT_SYMBOL(ieee80211_scan_completed); | |
336 | ||
f3b85252 JB |
337 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
338 | { | |
339 | struct ieee80211_sub_if_data *sdata; | |
340 | ||
341 | /* | |
342 | * Hardware/driver doesn't support hw_scan, so use software | |
343 | * scanning instead. First send a nullfunc frame with power save | |
344 | * bit on so that AP will buffer the frames for us while we are not | |
345 | * listening, then send probe requests to each channel and wait for | |
346 | * the responses. After all channels are scanned, tune back to the | |
347 | * original channel and send a nullfunc frame with power save bit | |
348 | * off to trigger the AP to send us all the buffered frames. | |
349 | * | |
350 | * Note that while local->sw_scanning is true everything else but | |
351 | * nullfunc frames and probe requests will be dropped in | |
352 | * ieee80211_tx_h_check_assoc(). | |
353 | */ | |
24487981 | 354 | drv_sw_scan_start(local); |
f3b85252 JB |
355 | |
356 | mutex_lock(&local->iflist_mtx); | |
357 | list_for_each_entry(sdata, &local->interfaces, list) { | |
358 | if (!netif_running(sdata->dev)) | |
359 | continue; | |
360 | ||
361 | /* disable beaconing */ | |
362 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
363 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
364 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
365 | ieee80211_bss_info_change_notify( |
366 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
f3b85252 | 367 | |
142b9f50 HS |
368 | /* |
369 | * only handle non-STA interfaces here, STA interfaces | |
370 | * are handled in the scan state machine | |
371 | */ | |
372 | if (sdata->vif.type != NL80211_IFTYPE_STATION) | |
f3b85252 JB |
373 | netif_tx_stop_all_queues(sdata->dev); |
374 | } | |
375 | mutex_unlock(&local->iflist_mtx); | |
376 | ||
2fb3f028 | 377 | local->scan_state = SCAN_DECISION; |
f3b85252 JB |
378 | local->scan_channel_idx = 0; |
379 | ||
3b8d81e0 | 380 | spin_lock_bh(&local->filter_lock); |
f3b85252 | 381 | local->filter_flags |= FIF_BCN_PRBRESP_PROMISC; |
24487981 JB |
382 | drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC, |
383 | &local->filter_flags, | |
3b8d81e0 JB |
384 | local->mc_count, |
385 | local->mc_list); | |
386 | spin_unlock_bh(&local->filter_lock); | |
f3b85252 JB |
387 | |
388 | /* TODO: start scan as soon as all nullfunc frames are ACKed */ | |
389 | queue_delayed_work(local->hw.workqueue, &local->scan_work, | |
390 | IEEE80211_CHANNEL_TIME); | |
391 | ||
392 | return 0; | |
393 | } | |
394 | ||
395 | ||
396 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
397 | struct cfg80211_scan_request *req) | |
398 | { | |
399 | struct ieee80211_local *local = sdata->local; | |
400 | struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; | |
401 | int rc; | |
402 | ||
403 | if (local->scan_req) | |
404 | return -EBUSY; | |
405 | ||
406 | if (local->ops->hw_scan) { | |
407 | u8 *ies; | |
408 | int ielen; | |
409 | ||
410 | ies = kmalloc(2 + IEEE80211_MAX_SSID_LEN + | |
411 | local->scan_ies_len + req->ie_len, GFP_KERNEL); | |
412 | if (!ies) | |
413 | return -ENOMEM; | |
414 | ||
415 | ielen = ieee80211_build_preq_ies(local, ies, | |
416 | req->ie, req->ie_len); | |
417 | local->orig_ies = req->ie; | |
418 | local->orig_ies_len = req->ie_len; | |
419 | req->ie = ies; | |
420 | req->ie_len = ielen; | |
421 | } | |
422 | ||
423 | local->scan_req = req; | |
424 | local->scan_sdata = sdata; | |
425 | ||
426 | if (req != &local->int_scan_req && | |
427 | sdata->vif.type == NL80211_IFTYPE_STATION && | |
77fdaa12 JB |
428 | !list_empty(&ifmgd->work_list)) { |
429 | /* actually wait for the work it's doing to finish/time out */ | |
f3b85252 JB |
430 | set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request); |
431 | return 0; | |
432 | } | |
433 | ||
434 | if (local->ops->hw_scan) | |
fbe9c429 | 435 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 436 | else |
fbe9c429 | 437 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
f3b85252 JB |
438 | /* |
439 | * Kicking off the scan need not be protected, | |
440 | * only the scan variable stuff, since now | |
441 | * local->scan_req is assigned and other callers | |
442 | * will abort their scan attempts. | |
443 | * | |
444 | * This avoids getting a scan_mtx -> iflist_mtx | |
445 | * dependency, so that the scan completed calls | |
446 | * have more locking freedom. | |
447 | */ | |
5cff20e6 JB |
448 | |
449 | ieee80211_recalc_idle(local); | |
f3b85252 JB |
450 | mutex_unlock(&local->scan_mtx); |
451 | ||
452 | if (local->ops->hw_scan) | |
24487981 | 453 | rc = drv_hw_scan(local, local->scan_req); |
f3b85252 JB |
454 | else |
455 | rc = ieee80211_start_sw_scan(local); | |
456 | ||
457 | mutex_lock(&local->scan_mtx); | |
458 | ||
459 | if (rc) { | |
fbe9c429 | 460 | if (local->ops->hw_scan) |
f3b85252 | 461 | ieee80211_restore_scan_ies(local); |
fbe9c429 | 462 | local->scanning = 0; |
f3b85252 | 463 | |
5cff20e6 JB |
464 | ieee80211_recalc_idle(local); |
465 | ||
f3b85252 JB |
466 | local->scan_req = NULL; |
467 | local->scan_sdata = NULL; | |
468 | } | |
469 | ||
470 | return rc; | |
471 | } | |
472 | ||
2fb3f028 HS |
473 | static int ieee80211_scan_state_decision(struct ieee80211_local *local, |
474 | unsigned long *next_delay) | |
7d3be3cc | 475 | { |
142b9f50 HS |
476 | bool associated = false; |
477 | struct ieee80211_sub_if_data *sdata; | |
478 | ||
479 | /* if no more bands/channels left, complete scan and advance to the idle state */ | |
7d3be3cc HS |
480 | if (local->scan_channel_idx >= local->scan_req->n_channels) { |
481 | ieee80211_scan_completed(&local->hw, false); | |
482 | return 1; | |
483 | } | |
2fb3f028 | 484 | |
142b9f50 HS |
485 | /* check if at least one STA interface is associated */ |
486 | mutex_lock(&local->iflist_mtx); | |
487 | list_for_each_entry(sdata, &local->interfaces, list) { | |
488 | if (!netif_running(sdata->dev)) | |
489 | continue; | |
490 | ||
491 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
492 | if (sdata->u.mgd.associated) { | |
493 | associated = true; | |
494 | break; | |
495 | } | |
496 | } | |
497 | } | |
498 | mutex_unlock(&local->iflist_mtx); | |
499 | ||
500 | if (local->scan_channel) { | |
501 | /* | |
502 | * we're currently scanning a different channel, let's | |
503 | * switch back to the operating channel now if at least | |
504 | * one interface is associated. Otherwise just scan the | |
505 | * next channel | |
506 | */ | |
507 | if (associated) | |
508 | local->scan_state = SCAN_ENTER_OPER_CHANNEL; | |
509 | else | |
510 | local->scan_state = SCAN_SET_CHANNEL; | |
511 | } else { | |
512 | /* | |
513 | * we're on the operating channel currently, let's | |
514 | * leave that channel now to scan another one | |
515 | */ | |
516 | local->scan_state = SCAN_LEAVE_OPER_CHANNEL; | |
517 | } | |
518 | ||
2fb3f028 | 519 | *next_delay = 0; |
2fb3f028 HS |
520 | return 0; |
521 | } | |
522 | ||
142b9f50 HS |
523 | static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, |
524 | unsigned long *next_delay) | |
525 | { | |
526 | struct ieee80211_sub_if_data *sdata; | |
527 | ||
528 | /* | |
529 | * notify the AP about us leaving the channel and stop all STA interfaces | |
530 | */ | |
531 | mutex_lock(&local->iflist_mtx); | |
532 | list_for_each_entry(sdata, &local->interfaces, list) { | |
533 | if (!netif_running(sdata->dev)) | |
534 | continue; | |
535 | ||
536 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
537 | netif_tx_stop_all_queues(sdata->dev); | |
538 | if (sdata->u.mgd.associated) | |
539 | ieee80211_scan_ps_enable(sdata); | |
540 | } | |
541 | } | |
542 | mutex_unlock(&local->iflist_mtx); | |
543 | ||
544 | __set_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
545 | ||
546 | /* advance to the next channel to be scanned */ | |
547 | *next_delay = HZ / 10; | |
548 | local->scan_state = SCAN_SET_CHANNEL; | |
549 | } | |
550 | ||
551 | static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, | |
552 | unsigned long *next_delay) | |
553 | { | |
554 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
555 | ||
556 | /* switch back to the operating channel */ | |
557 | local->scan_channel = NULL; | |
558 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
559 | ||
560 | /* | |
561 | * notify the AP about us being back and restart all STA interfaces | |
562 | */ | |
563 | mutex_lock(&local->iflist_mtx); | |
564 | list_for_each_entry(sdata, &local->interfaces, list) { | |
565 | if (!netif_running(sdata->dev)) | |
566 | continue; | |
567 | ||
568 | /* Tell AP we're back */ | |
569 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
570 | if (sdata->u.mgd.associated) | |
571 | ieee80211_scan_ps_disable(sdata); | |
572 | netif_tx_wake_all_queues(sdata->dev); | |
573 | } | |
574 | } | |
575 | mutex_unlock(&local->iflist_mtx); | |
576 | ||
577 | __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
578 | ||
579 | *next_delay = HZ / 5; | |
580 | local->scan_state = SCAN_DECISION; | |
581 | } | |
582 | ||
2fb3f028 HS |
583 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
584 | unsigned long *next_delay) | |
585 | { | |
586 | int skip; | |
587 | struct ieee80211_channel *chan; | |
588 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
589 | ||
7d3be3cc HS |
590 | skip = 0; |
591 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
592 | ||
593 | if (chan->flags & IEEE80211_CHAN_DISABLED || | |
594 | (sdata->vif.type == NL80211_IFTYPE_ADHOC && | |
595 | chan->flags & IEEE80211_CHAN_NO_IBSS)) | |
596 | skip = 1; | |
597 | ||
598 | if (!skip) { | |
599 | local->scan_channel = chan; | |
600 | if (ieee80211_hw_config(local, | |
601 | IEEE80211_CONF_CHANGE_CHANNEL)) | |
602 | skip = 1; | |
603 | } | |
604 | ||
605 | /* advance state machine to next channel/band */ | |
606 | local->scan_channel_idx++; | |
607 | ||
608 | if (skip) | |
2fb3f028 | 609 | return; |
7d3be3cc HS |
610 | |
611 | /* | |
612 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
613 | * (which unfortunately doesn't say _why_ step a) is done, | |
614 | * but it waits for the probe delay or until a frame is | |
615 | * received - and the received frame would update the NAV). | |
616 | * For now, we do not support waiting until a frame is | |
617 | * received. | |
618 | * | |
619 | * In any case, it is not necessary for a passive scan. | |
620 | */ | |
621 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
622 | !local->scan_req->n_ssids) { | |
623 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
2fb3f028 HS |
624 | local->scan_state = SCAN_DECISION; |
625 | return; | |
7d3be3cc HS |
626 | } |
627 | ||
2fb3f028 | 628 | /* active scan, send probes */ |
7d3be3cc HS |
629 | *next_delay = IEEE80211_PROBE_DELAY; |
630 | local->scan_state = SCAN_SEND_PROBE; | |
7d3be3cc HS |
631 | } |
632 | ||
633 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
634 | unsigned long *next_delay) | |
635 | { | |
636 | int i; | |
637 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
638 | ||
639 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
640 | ieee80211_send_probe_req( | |
641 | sdata, NULL, | |
642 | local->scan_req->ssids[i].ssid, | |
643 | local->scan_req->ssids[i].ssid_len, | |
644 | local->scan_req->ie, local->scan_req->ie_len); | |
645 | ||
646 | /* | |
647 | * After sending probe requests, wait for probe responses | |
648 | * on the channel. | |
649 | */ | |
650 | *next_delay = IEEE80211_CHANNEL_TIME; | |
2fb3f028 | 651 | local->scan_state = SCAN_DECISION; |
7d3be3cc HS |
652 | } |
653 | ||
c2b13452 | 654 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
655 | { |
656 | struct ieee80211_local *local = | |
657 | container_of(work, struct ieee80211_local, scan_work.work); | |
658 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
0a51b27e JB |
659 | unsigned long next_delay = 0; |
660 | ||
f3b85252 JB |
661 | mutex_lock(&local->scan_mtx); |
662 | if (!sdata || !local->scan_req) { | |
663 | mutex_unlock(&local->scan_mtx); | |
664 | return; | |
665 | } | |
666 | ||
fbe9c429 | 667 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
668 | struct cfg80211_scan_request *req = local->scan_req; |
669 | int rc; | |
670 | ||
671 | local->scan_req = NULL; | |
672 | ||
673 | rc = __ieee80211_start_scan(sdata, req); | |
674 | mutex_unlock(&local->scan_mtx); | |
675 | ||
676 | if (rc) | |
677 | ieee80211_scan_completed(&local->hw, true); | |
678 | return; | |
679 | } | |
680 | ||
681 | mutex_unlock(&local->scan_mtx); | |
682 | ||
5bc75728 JB |
683 | /* |
684 | * Avoid re-scheduling when the sdata is going away. | |
685 | */ | |
f3b85252 JB |
686 | if (!netif_running(sdata->dev)) { |
687 | ieee80211_scan_completed(&local->hw, true); | |
0a51b27e | 688 | return; |
f3b85252 | 689 | } |
0a51b27e | 690 | |
f502d09b HS |
691 | /* |
692 | * as long as no delay is required advance immediately | |
693 | * without scheduling a new work | |
694 | */ | |
695 | do { | |
696 | switch (local->scan_state) { | |
2fb3f028 HS |
697 | case SCAN_DECISION: |
698 | if (ieee80211_scan_state_decision(local, &next_delay)) | |
f502d09b HS |
699 | return; |
700 | break; | |
2fb3f028 HS |
701 | case SCAN_SET_CHANNEL: |
702 | ieee80211_scan_state_set_channel(local, &next_delay); | |
703 | break; | |
f502d09b HS |
704 | case SCAN_SEND_PROBE: |
705 | ieee80211_scan_state_send_probe(local, &next_delay); | |
706 | break; | |
142b9f50 HS |
707 | case SCAN_LEAVE_OPER_CHANNEL: |
708 | ieee80211_scan_state_leave_oper_channel(local, &next_delay); | |
709 | break; | |
710 | case SCAN_ENTER_OPER_CHANNEL: | |
711 | ieee80211_scan_state_enter_oper_channel(local, &next_delay); | |
712 | break; | |
f502d09b HS |
713 | } |
714 | } while (next_delay == 0); | |
0a51b27e | 715 | |
5bc75728 JB |
716 | queue_delayed_work(local->hw.workqueue, &local->scan_work, |
717 | next_delay); | |
0a51b27e JB |
718 | } |
719 | ||
f3b85252 JB |
720 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
721 | struct cfg80211_scan_request *req) | |
0a51b27e | 722 | { |
f3b85252 | 723 | int res; |
de95a54b | 724 | |
f3b85252 JB |
725 | mutex_lock(&sdata->local->scan_mtx); |
726 | res = __ieee80211_start_scan(sdata, req); | |
727 | mutex_unlock(&sdata->local->scan_mtx); | |
0a51b27e | 728 | |
f3b85252 | 729 | return res; |
0a51b27e JB |
730 | } |
731 | ||
f3b85252 JB |
732 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
733 | const u8 *ssid, u8 ssid_len) | |
0a51b27e | 734 | { |
0a51b27e | 735 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 736 | int ret = -EBUSY; |
2a519311 | 737 | |
f3b85252 | 738 | mutex_lock(&local->scan_mtx); |
0a51b27e | 739 | |
f3b85252 JB |
740 | /* busy scanning */ |
741 | if (local->scan_req) | |
742 | goto unlock; | |
9116dd01 | 743 | |
f3b85252 JB |
744 | memcpy(local->int_scan_req.ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
745 | local->int_scan_req.ssids[0].ssid_len = ssid_len; | |
9116dd01 | 746 | |
f3b85252 JB |
747 | ret = __ieee80211_start_scan(sdata, &sdata->local->int_scan_req); |
748 | unlock: | |
749 | mutex_unlock(&local->scan_mtx); | |
750 | return ret; | |
0a51b27e | 751 | } |
5bb644a0 JB |
752 | |
753 | void ieee80211_scan_cancel(struct ieee80211_local *local) | |
754 | { | |
755 | bool swscan; | |
756 | ||
757 | cancel_delayed_work_sync(&local->scan_work); | |
758 | ||
759 | /* | |
760 | * Only call this function when a scan can't be | |
761 | * queued -- mostly at suspend under RTNL. | |
762 | */ | |
763 | mutex_lock(&local->scan_mtx); | |
fbe9c429 | 764 | swscan = test_bit(SCAN_SW_SCANNING, &local->scanning); |
5bb644a0 JB |
765 | mutex_unlock(&local->scan_mtx); |
766 | ||
767 | if (swscan) | |
768 | ieee80211_scan_completed(&local->hw, true); | |
769 | } |