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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 | ||
0a51b27e | 15 | #include <linux/if_arp.h> |
078e1e60 | 16 | #include <linux/rtnetlink.h> |
0a51b27e | 17 | #include <net/mac80211.h> |
0a51b27e JB |
18 | |
19 | #include "ieee80211_i.h" | |
24487981 | 20 | #include "driver-ops.h" |
5484e237 | 21 | #include "mesh.h" |
0a51b27e JB |
22 | |
23 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
24 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 25 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 26 | |
c2b13452 | 27 | struct ieee80211_bss * |
5484e237 JB |
28 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
29 | u8 *ssid, u8 ssid_len) | |
30 | { | |
0c1ad2ca JB |
31 | struct cfg80211_bss *cbss; |
32 | ||
33 | cbss = cfg80211_get_bss(local->hw.wiphy, | |
34 | ieee80211_get_channel(local->hw.wiphy, freq), | |
35 | bssid, ssid, ssid_len, 0, 0); | |
36 | if (!cbss) | |
37 | return NULL; | |
38 | return (void *)cbss->priv; | |
5484e237 JB |
39 | } |
40 | ||
00d3f14c | 41 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 42 | { |
0c1ad2ca | 43 | struct ieee80211_bss *bss = (void *)cbss->priv; |
5484e237 | 44 | |
5484e237 JB |
45 | kfree(bss_mesh_id(bss)); |
46 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
47 | } |
48 | ||
49 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 50 | struct ieee80211_bss *bss) |
5484e237 | 51 | { |
0c1ad2ca JB |
52 | if (!bss) |
53 | return; | |
54 | cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); | |
5484e237 JB |
55 | } |
56 | ||
c2b13452 | 57 | struct ieee80211_bss * |
5484e237 JB |
58 | ieee80211_bss_info_update(struct ieee80211_local *local, |
59 | struct ieee80211_rx_status *rx_status, | |
60 | struct ieee80211_mgmt *mgmt, | |
61 | size_t len, | |
62 | struct ieee802_11_elems *elems, | |
2a519311 JB |
63 | struct ieee80211_channel *channel, |
64 | bool beacon) | |
5484e237 | 65 | { |
0c1ad2ca | 66 | struct cfg80211_bss *cbss; |
c2b13452 | 67 | struct ieee80211_bss *bss; |
00d3f14c | 68 | int clen; |
2a519311 JB |
69 | s32 signal = 0; |
70 | ||
77965c97 | 71 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 72 | signal = rx_status->signal * 100; |
77965c97 | 73 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 74 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 75 | |
0c1ad2ca JB |
76 | cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
77 | mgmt, len, signal, GFP_ATOMIC); | |
5484e237 | 78 | |
0c1ad2ca | 79 | if (!cbss) |
00d3f14c JB |
80 | return NULL; |
81 | ||
0c1ad2ca JB |
82 | cbss->free_priv = ieee80211_rx_bss_free; |
83 | bss = (void *)cbss->priv; | |
5484e237 JB |
84 | |
85 | /* save the ERP value so that it is available at association time */ | |
86 | if (elems->erp_info && elems->erp_info_len >= 1) { | |
87 | bss->erp_value = elems->erp_info[0]; | |
88 | bss->has_erp_value = 1; | |
89 | } | |
90 | ||
5484e237 JB |
91 | if (elems->tim) { |
92 | struct ieee80211_tim_ie *tim_ie = | |
93 | (struct ieee80211_tim_ie *)elems->tim; | |
94 | bss->dtim_period = tim_ie->dtim_period; | |
95 | } | |
96 | ||
6a211bf1 JB |
97 | /* set default value for buggy AP/no TIM element */ |
98 | if (bss->dtim_period == 0) | |
5484e237 JB |
99 | bss->dtim_period = 1; |
100 | ||
101 | bss->supp_rates_len = 0; | |
102 | if (elems->supp_rates) { | |
103 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
104 | if (clen > elems->supp_rates_len) | |
105 | clen = elems->supp_rates_len; | |
106 | memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, | |
107 | clen); | |
108 | bss->supp_rates_len += clen; | |
109 | } | |
110 | if (elems->ext_supp_rates) { | |
111 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
112 | if (clen > elems->ext_supp_rates_len) | |
113 | clen = elems->ext_supp_rates_len; | |
114 | memcpy(&bss->supp_rates[bss->supp_rates_len], | |
115 | elems->ext_supp_rates, clen); | |
116 | bss->supp_rates_len += clen; | |
117 | } | |
118 | ||
5484e237 JB |
119 | bss->wmm_used = elems->wmm_param || elems->wmm_info; |
120 | ||
121 | if (!beacon) | |
122 | bss->last_probe_resp = jiffies; | |
123 | ||
5484e237 JB |
124 | return bss; |
125 | } | |
0a51b27e | 126 | |
98c8fccf | 127 | ieee80211_rx_result |
f1d58c25 | 128 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 129 | { |
f1d58c25 | 130 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 131 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 132 | struct ieee80211_bss *bss; |
98c8fccf JB |
133 | u8 *elements; |
134 | struct ieee80211_channel *channel; | |
135 | size_t baselen; | |
136 | int freq; | |
137 | __le16 fc; | |
138 | bool presp, beacon = false; | |
139 | struct ieee802_11_elems elems; | |
140 | ||
141 | if (skb->len < 2) | |
142 | return RX_DROP_UNUSABLE; | |
143 | ||
144 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
145 | fc = mgmt->frame_control; | |
146 | ||
147 | if (ieee80211_is_ctl(fc)) | |
148 | return RX_CONTINUE; | |
149 | ||
150 | if (skb->len < 24) | |
151 | return RX_DROP_MONITOR; | |
152 | ||
153 | presp = ieee80211_is_probe_resp(fc); | |
154 | if (presp) { | |
155 | /* ignore ProbeResp to foreign address */ | |
47846c9b | 156 | if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) |
98c8fccf JB |
157 | return RX_DROP_MONITOR; |
158 | ||
159 | presp = true; | |
160 | elements = mgmt->u.probe_resp.variable; | |
161 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
162 | } else { | |
163 | beacon = ieee80211_is_beacon(fc); | |
164 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
165 | elements = mgmt->u.beacon.variable; | |
166 | } | |
167 | ||
168 | if (!presp && !beacon) | |
169 | return RX_CONTINUE; | |
170 | ||
171 | if (baselen > skb->len) | |
172 | return RX_DROP_MONITOR; | |
173 | ||
174 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
175 | ||
176 | if (elems.ds_params && elems.ds_params_len == 1) | |
177 | freq = ieee80211_channel_to_frequency(elems.ds_params[0]); | |
178 | else | |
179 | freq = rx_status->freq; | |
180 | ||
181 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
182 | ||
183 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
184 | return RX_DROP_MONITOR; | |
185 | ||
186 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
187 | mgmt, skb->len, &elems, | |
2a519311 | 188 | channel, beacon); |
d048e503 JM |
189 | if (bss) |
190 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf JB |
191 | |
192 | dev_kfree_skb(skb); | |
193 | return RX_QUEUED; | |
194 | } | |
195 | ||
4d36ec58 JB |
196 | /* return false if no more work */ |
197 | static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) | |
198 | { | |
199 | struct cfg80211_scan_request *req = local->scan_req; | |
200 | enum ieee80211_band band; | |
201 | int i, ielen, n_chans; | |
202 | ||
203 | do { | |
204 | if (local->hw_scan_band == IEEE80211_NUM_BANDS) | |
205 | return false; | |
206 | ||
207 | band = local->hw_scan_band; | |
208 | n_chans = 0; | |
209 | for (i = 0; i < req->n_channels; i++) { | |
210 | if (req->channels[i]->band == band) { | |
211 | local->hw_scan_req->channels[n_chans] = | |
212 | req->channels[i]; | |
213 | n_chans++; | |
214 | } | |
215 | } | |
216 | ||
217 | local->hw_scan_band++; | |
218 | } while (!n_chans); | |
219 | ||
220 | local->hw_scan_req->n_channels = n_chans; | |
221 | ||
222 | ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, | |
223 | req->ie, req->ie_len, band); | |
224 | local->hw_scan_req->ie_len = ielen; | |
225 | ||
226 | return true; | |
227 | } | |
228 | ||
2a519311 | 229 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) |
0a51b27e JB |
230 | { |
231 | struct ieee80211_local *local = hw_to_local(hw); | |
f3b85252 | 232 | bool was_hw_scan; |
0a51b27e | 233 | |
f3b85252 | 234 | mutex_lock(&local->scan_mtx); |
5bc75728 | 235 | |
6d3560d4 JB |
236 | /* |
237 | * It's ok to abort a not-yet-running scan (that | |
238 | * we have one at all will be verified by checking | |
239 | * local->scan_req next), but not to complete it | |
240 | * successfully. | |
241 | */ | |
242 | if (WARN_ON(!local->scanning && !aborted)) | |
243 | aborted = true; | |
5bc75728 | 244 | |
f3b85252 JB |
245 | if (WARN_ON(!local->scan_req)) { |
246 | mutex_unlock(&local->scan_mtx); | |
247 | return; | |
de95a54b JB |
248 | } |
249 | ||
4d36ec58 JB |
250 | was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
251 | if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { | |
252 | ieee80211_queue_delayed_work(&local->hw, | |
253 | &local->scan_work, 0); | |
254 | mutex_unlock(&local->scan_mtx); | |
255 | return; | |
256 | } | |
257 | ||
258 | kfree(local->hw_scan_req); | |
259 | local->hw_scan_req = NULL; | |
f3b85252 | 260 | |
5ba63533 | 261 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
262 | cfg80211_scan_done(local->scan_req, aborted); |
263 | local->scan_req = NULL; | |
15db0b7f | 264 | local->scan_sdata = NULL; |
2a519311 | 265 | |
fbe9c429 | 266 | local->scanning = 0; |
58905ca5 | 267 | local->scan_channel = NULL; |
f3b85252 JB |
268 | |
269 | /* we only have to protect scan_req and hw/sw scan */ | |
270 | mutex_unlock(&local->scan_mtx); | |
271 | ||
e8975581 | 272 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); |
5cff20e6 JB |
273 | if (was_hw_scan) |
274 | goto done; | |
0a51b27e | 275 | |
3ac64bee | 276 | ieee80211_configure_filter(local); |
0a51b27e | 277 | |
24487981 | 278 | drv_sw_scan_complete(local); |
80e775bf | 279 | |
b203ffc3 | 280 | ieee80211_offchannel_return(local, true); |
0a51b27e JB |
281 | |
282 | done: | |
5cff20e6 | 283 | ieee80211_recalc_idle(local); |
0a51b27e | 284 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 285 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 286 | ieee80211_mesh_notify_scan_completed(local); |
81ac3462 | 287 | ieee80211_queue_work(&local->hw, &local->work_work); |
0a51b27e JB |
288 | } |
289 | EXPORT_SYMBOL(ieee80211_scan_completed); | |
290 | ||
f3b85252 JB |
291 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
292 | { | |
f3b85252 JB |
293 | /* |
294 | * Hardware/driver doesn't support hw_scan, so use software | |
295 | * scanning instead. First send a nullfunc frame with power save | |
296 | * bit on so that AP will buffer the frames for us while we are not | |
297 | * listening, then send probe requests to each channel and wait for | |
298 | * the responses. After all channels are scanned, tune back to the | |
299 | * original channel and send a nullfunc frame with power save bit | |
300 | * off to trigger the AP to send us all the buffered frames. | |
301 | * | |
302 | * Note that while local->sw_scanning is true everything else but | |
303 | * nullfunc frames and probe requests will be dropped in | |
304 | * ieee80211_tx_h_check_assoc(). | |
305 | */ | |
24487981 | 306 | drv_sw_scan_start(local); |
f3b85252 | 307 | |
b203ffc3 | 308 | ieee80211_offchannel_stop_beaconing(local); |
f3b85252 | 309 | |
977923b0 | 310 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
311 | local->scan_channel_idx = 0; |
312 | ||
a80f7c0b JB |
313 | drv_flush(local, false); |
314 | ||
3ac64bee | 315 | ieee80211_configure_filter(local); |
f3b85252 | 316 | |
42935eca LR |
317 | ieee80211_queue_delayed_work(&local->hw, |
318 | &local->scan_work, | |
319 | IEEE80211_CHANNEL_TIME); | |
f3b85252 JB |
320 | |
321 | return 0; | |
322 | } | |
323 | ||
324 | ||
325 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
326 | struct cfg80211_scan_request *req) | |
327 | { | |
328 | struct ieee80211_local *local = sdata->local; | |
f3b85252 JB |
329 | int rc; |
330 | ||
331 | if (local->scan_req) | |
332 | return -EBUSY; | |
333 | ||
334 | if (local->ops->hw_scan) { | |
335 | u8 *ies; | |
f3b85252 | 336 | |
4d36ec58 JB |
337 | local->hw_scan_req = kmalloc( |
338 | sizeof(*local->hw_scan_req) + | |
339 | req->n_channels * sizeof(req->channels[0]) + | |
340 | 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + | |
341 | req->ie_len, GFP_KERNEL); | |
342 | if (!local->hw_scan_req) | |
f3b85252 JB |
343 | return -ENOMEM; |
344 | ||
4d36ec58 JB |
345 | local->hw_scan_req->ssids = req->ssids; |
346 | local->hw_scan_req->n_ssids = req->n_ssids; | |
347 | ies = (u8 *)local->hw_scan_req + | |
348 | sizeof(*local->hw_scan_req) + | |
349 | req->n_channels * sizeof(req->channels[0]); | |
350 | local->hw_scan_req->ie = ies; | |
351 | ||
352 | local->hw_scan_band = 0; | |
f3b85252 JB |
353 | } |
354 | ||
355 | local->scan_req = req; | |
356 | local->scan_sdata = sdata; | |
357 | ||
af6b6374 JB |
358 | if (!list_empty(&local->work_list)) { |
359 | /* wait for the work to finish/time out */ | |
f3b85252 JB |
360 | return 0; |
361 | } | |
362 | ||
363 | if (local->ops->hw_scan) | |
fbe9c429 | 364 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 365 | else |
fbe9c429 | 366 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
f3b85252 JB |
367 | /* |
368 | * Kicking off the scan need not be protected, | |
369 | * only the scan variable stuff, since now | |
370 | * local->scan_req is assigned and other callers | |
371 | * will abort their scan attempts. | |
372 | * | |
373 | * This avoids getting a scan_mtx -> iflist_mtx | |
374 | * dependency, so that the scan completed calls | |
375 | * have more locking freedom. | |
376 | */ | |
5cff20e6 JB |
377 | |
378 | ieee80211_recalc_idle(local); | |
f3b85252 JB |
379 | mutex_unlock(&local->scan_mtx); |
380 | ||
4d36ec58 JB |
381 | if (local->ops->hw_scan) { |
382 | WARN_ON(!ieee80211_prep_hw_scan(local)); | |
383 | rc = drv_hw_scan(local, local->hw_scan_req); | |
384 | } else | |
f3b85252 JB |
385 | rc = ieee80211_start_sw_scan(local); |
386 | ||
387 | mutex_lock(&local->scan_mtx); | |
388 | ||
389 | if (rc) { | |
4d36ec58 JB |
390 | kfree(local->hw_scan_req); |
391 | local->hw_scan_req = NULL; | |
fbe9c429 | 392 | local->scanning = 0; |
f3b85252 | 393 | |
5cff20e6 JB |
394 | ieee80211_recalc_idle(local); |
395 | ||
f3b85252 JB |
396 | local->scan_req = NULL; |
397 | local->scan_sdata = NULL; | |
398 | } | |
399 | ||
400 | return rc; | |
401 | } | |
402 | ||
2fb3f028 HS |
403 | static int ieee80211_scan_state_decision(struct ieee80211_local *local, |
404 | unsigned long *next_delay) | |
7d3be3cc | 405 | { |
142b9f50 HS |
406 | bool associated = false; |
407 | struct ieee80211_sub_if_data *sdata; | |
408 | ||
409 | /* if no more bands/channels left, complete scan and advance to the idle state */ | |
7d3be3cc HS |
410 | if (local->scan_channel_idx >= local->scan_req->n_channels) { |
411 | ieee80211_scan_completed(&local->hw, false); | |
412 | return 1; | |
413 | } | |
2fb3f028 | 414 | |
142b9f50 HS |
415 | /* check if at least one STA interface is associated */ |
416 | mutex_lock(&local->iflist_mtx); | |
417 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 418 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
419 | continue; |
420 | ||
421 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
422 | if (sdata->u.mgd.associated) { | |
423 | associated = true; | |
424 | break; | |
425 | } | |
426 | } | |
427 | } | |
428 | mutex_unlock(&local->iflist_mtx); | |
429 | ||
430 | if (local->scan_channel) { | |
431 | /* | |
432 | * we're currently scanning a different channel, let's | |
433 | * switch back to the operating channel now if at least | |
434 | * one interface is associated. Otherwise just scan the | |
435 | * next channel | |
436 | */ | |
437 | if (associated) | |
977923b0 | 438 | local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; |
142b9f50 | 439 | else |
977923b0 | 440 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
441 | } else { |
442 | /* | |
443 | * we're on the operating channel currently, let's | |
444 | * leave that channel now to scan another one | |
445 | */ | |
977923b0 | 446 | local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; |
142b9f50 HS |
447 | } |
448 | ||
2fb3f028 | 449 | *next_delay = 0; |
2fb3f028 HS |
450 | return 0; |
451 | } | |
452 | ||
142b9f50 HS |
453 | static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, |
454 | unsigned long *next_delay) | |
455 | { | |
b203ffc3 | 456 | ieee80211_offchannel_stop_station(local); |
142b9f50 HS |
457 | |
458 | __set_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
459 | ||
a80f7c0b JB |
460 | /* |
461 | * What if the nullfunc frames didn't arrive? | |
462 | */ | |
463 | drv_flush(local, false); | |
464 | if (local->ops->flush) | |
465 | *next_delay = 0; | |
466 | else | |
467 | *next_delay = HZ / 10; | |
468 | ||
142b9f50 | 469 | /* advance to the next channel to be scanned */ |
977923b0 | 470 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
471 | } |
472 | ||
473 | static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, | |
474 | unsigned long *next_delay) | |
475 | { | |
142b9f50 HS |
476 | /* switch back to the operating channel */ |
477 | local->scan_channel = NULL; | |
478 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
479 | ||
480 | /* | |
b203ffc3 JM |
481 | * Only re-enable station mode interface now; beaconing will be |
482 | * re-enabled once the full scan has been completed. | |
142b9f50 | 483 | */ |
b203ffc3 | 484 | ieee80211_offchannel_return(local, false); |
142b9f50 HS |
485 | |
486 | __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
487 | ||
488 | *next_delay = HZ / 5; | |
977923b0 | 489 | local->next_scan_state = SCAN_DECISION; |
142b9f50 HS |
490 | } |
491 | ||
2fb3f028 HS |
492 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
493 | unsigned long *next_delay) | |
494 | { | |
495 | int skip; | |
496 | struct ieee80211_channel *chan; | |
2fb3f028 | 497 | |
7d3be3cc HS |
498 | skip = 0; |
499 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
500 | ||
584991dc JB |
501 | local->scan_channel = chan; |
502 | if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) | |
7d3be3cc HS |
503 | skip = 1; |
504 | ||
7d3be3cc HS |
505 | /* advance state machine to next channel/band */ |
506 | local->scan_channel_idx++; | |
507 | ||
0ee9c13c HS |
508 | if (skip) { |
509 | /* if we skip this channel return to the decision state */ | |
510 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 511 | return; |
0ee9c13c | 512 | } |
7d3be3cc HS |
513 | |
514 | /* | |
515 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
516 | * (which unfortunately doesn't say _why_ step a) is done, | |
517 | * but it waits for the probe delay or until a frame is | |
518 | * received - and the received frame would update the NAV). | |
519 | * For now, we do not support waiting until a frame is | |
520 | * received. | |
521 | * | |
522 | * In any case, it is not necessary for a passive scan. | |
523 | */ | |
524 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
525 | !local->scan_req->n_ssids) { | |
526 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 527 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 528 | return; |
7d3be3cc HS |
529 | } |
530 | ||
2fb3f028 | 531 | /* active scan, send probes */ |
7d3be3cc | 532 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 533 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
534 | } |
535 | ||
536 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
537 | unsigned long *next_delay) | |
538 | { | |
539 | int i; | |
540 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
541 | ||
542 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
543 | ieee80211_send_probe_req( | |
544 | sdata, NULL, | |
545 | local->scan_req->ssids[i].ssid, | |
546 | local->scan_req->ssids[i].ssid_len, | |
547 | local->scan_req->ie, local->scan_req->ie_len); | |
548 | ||
549 | /* | |
550 | * After sending probe requests, wait for probe responses | |
551 | * on the channel. | |
552 | */ | |
553 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 554 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
555 | } |
556 | ||
c2b13452 | 557 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
558 | { |
559 | struct ieee80211_local *local = | |
560 | container_of(work, struct ieee80211_local, scan_work.work); | |
561 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
0a51b27e JB |
562 | unsigned long next_delay = 0; |
563 | ||
f3b85252 JB |
564 | mutex_lock(&local->scan_mtx); |
565 | if (!sdata || !local->scan_req) { | |
566 | mutex_unlock(&local->scan_mtx); | |
567 | return; | |
568 | } | |
569 | ||
4d36ec58 JB |
570 | if (local->hw_scan_req) { |
571 | int rc = drv_hw_scan(local, local->hw_scan_req); | |
572 | mutex_unlock(&local->scan_mtx); | |
573 | if (rc) | |
574 | ieee80211_scan_completed(&local->hw, true); | |
575 | return; | |
576 | } | |
577 | ||
fbe9c429 | 578 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
579 | struct cfg80211_scan_request *req = local->scan_req; |
580 | int rc; | |
581 | ||
582 | local->scan_req = NULL; | |
15db0b7f | 583 | local->scan_sdata = NULL; |
f3b85252 JB |
584 | |
585 | rc = __ieee80211_start_scan(sdata, req); | |
586 | mutex_unlock(&local->scan_mtx); | |
587 | ||
588 | if (rc) | |
589 | ieee80211_scan_completed(&local->hw, true); | |
590 | return; | |
591 | } | |
592 | ||
593 | mutex_unlock(&local->scan_mtx); | |
594 | ||
5bc75728 JB |
595 | /* |
596 | * Avoid re-scheduling when the sdata is going away. | |
597 | */ | |
9607e6b6 | 598 | if (!ieee80211_sdata_running(sdata)) { |
f3b85252 | 599 | ieee80211_scan_completed(&local->hw, true); |
0a51b27e | 600 | return; |
f3b85252 | 601 | } |
0a51b27e | 602 | |
f502d09b HS |
603 | /* |
604 | * as long as no delay is required advance immediately | |
605 | * without scheduling a new work | |
606 | */ | |
607 | do { | |
977923b0 | 608 | switch (local->next_scan_state) { |
2fb3f028 HS |
609 | case SCAN_DECISION: |
610 | if (ieee80211_scan_state_decision(local, &next_delay)) | |
f502d09b HS |
611 | return; |
612 | break; | |
2fb3f028 HS |
613 | case SCAN_SET_CHANNEL: |
614 | ieee80211_scan_state_set_channel(local, &next_delay); | |
615 | break; | |
f502d09b HS |
616 | case SCAN_SEND_PROBE: |
617 | ieee80211_scan_state_send_probe(local, &next_delay); | |
618 | break; | |
142b9f50 HS |
619 | case SCAN_LEAVE_OPER_CHANNEL: |
620 | ieee80211_scan_state_leave_oper_channel(local, &next_delay); | |
621 | break; | |
622 | case SCAN_ENTER_OPER_CHANNEL: | |
623 | ieee80211_scan_state_enter_oper_channel(local, &next_delay); | |
624 | break; | |
f502d09b HS |
625 | } |
626 | } while (next_delay == 0); | |
0a51b27e | 627 | |
42935eca | 628 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
0a51b27e JB |
629 | } |
630 | ||
f3b85252 JB |
631 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
632 | struct cfg80211_scan_request *req) | |
0a51b27e | 633 | { |
f3b85252 | 634 | int res; |
de95a54b | 635 | |
f3b85252 JB |
636 | mutex_lock(&sdata->local->scan_mtx); |
637 | res = __ieee80211_start_scan(sdata, req); | |
638 | mutex_unlock(&sdata->local->scan_mtx); | |
0a51b27e | 639 | |
f3b85252 | 640 | return res; |
0a51b27e JB |
641 | } |
642 | ||
f3b85252 JB |
643 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
644 | const u8 *ssid, u8 ssid_len) | |
0a51b27e | 645 | { |
0a51b27e | 646 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 647 | int ret = -EBUSY; |
2a519311 | 648 | |
f3b85252 | 649 | mutex_lock(&local->scan_mtx); |
0a51b27e | 650 | |
f3b85252 JB |
651 | /* busy scanning */ |
652 | if (local->scan_req) | |
653 | goto unlock; | |
9116dd01 | 654 | |
5ba63533 JB |
655 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
656 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 657 | |
5ba63533 | 658 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 JB |
659 | unlock: |
660 | mutex_unlock(&local->scan_mtx); | |
661 | return ret; | |
0a51b27e | 662 | } |
5bb644a0 JB |
663 | |
664 | void ieee80211_scan_cancel(struct ieee80211_local *local) | |
665 | { | |
15db0b7f | 666 | bool abortscan; |
5bb644a0 JB |
667 | |
668 | cancel_delayed_work_sync(&local->scan_work); | |
669 | ||
670 | /* | |
671 | * Only call this function when a scan can't be | |
672 | * queued -- mostly at suspend under RTNL. | |
673 | */ | |
674 | mutex_lock(&local->scan_mtx); | |
15db0b7f JB |
675 | abortscan = test_bit(SCAN_SW_SCANNING, &local->scanning) || |
676 | (!local->scanning && local->scan_req); | |
5bb644a0 JB |
677 | mutex_unlock(&local->scan_mtx); |
678 | ||
15db0b7f | 679 | if (abortscan) |
5bb644a0 JB |
680 | ieee80211_scan_completed(&local->hw, true); |
681 | } |