Commit | Line | Data |
---|---|---|
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 | 20 | #include <net/mac80211.h> |
0a51b27e JB |
21 | |
22 | #include "ieee80211_i.h" | |
24487981 | 23 | #include "driver-ops.h" |
5484e237 | 24 | #include "mesh.h" |
0a51b27e JB |
25 | |
26 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
27 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 28 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 29 | |
c2b13452 | 30 | struct ieee80211_bss * |
5484e237 JB |
31 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
32 | u8 *ssid, u8 ssid_len) | |
33 | { | |
00d3f14c JB |
34 | return (void *)cfg80211_get_bss(local->hw.wiphy, |
35 | ieee80211_get_channel(local->hw.wiphy, | |
36 | freq), | |
37 | bssid, ssid, ssid_len, | |
38 | 0, 0); | |
5484e237 JB |
39 | } |
40 | ||
00d3f14c | 41 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 42 | { |
00d3f14c | 43 | struct ieee80211_bss *bss = (void *)cbss; |
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 | { |
00d3f14c | 52 | cfg80211_put_bss((struct cfg80211_bss *)bss); |
5484e237 JB |
53 | } |
54 | ||
c2b13452 | 55 | struct ieee80211_bss * |
5484e237 JB |
56 | ieee80211_bss_info_update(struct ieee80211_local *local, |
57 | struct ieee80211_rx_status *rx_status, | |
58 | struct ieee80211_mgmt *mgmt, | |
59 | size_t len, | |
60 | struct ieee802_11_elems *elems, | |
2a519311 JB |
61 | struct ieee80211_channel *channel, |
62 | bool beacon) | |
5484e237 | 63 | { |
c2b13452 | 64 | struct ieee80211_bss *bss; |
00d3f14c | 65 | int clen; |
2a519311 JB |
66 | s32 signal = 0; |
67 | ||
77965c97 | 68 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 69 | signal = rx_status->signal * 100; |
77965c97 | 70 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 71 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 72 | |
00d3f14c | 73 | bss = (void *)cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
77965c97 | 74 | mgmt, len, signal, GFP_ATOMIC); |
5484e237 | 75 | |
00d3f14c JB |
76 | if (!bss) |
77 | return NULL; | |
78 | ||
79 | bss->cbss.free_priv = ieee80211_rx_bss_free; | |
5484e237 JB |
80 | |
81 | /* save the ERP value so that it is available at association time */ | |
82 | if (elems->erp_info && elems->erp_info_len >= 1) { | |
83 | bss->erp_value = elems->erp_info[0]; | |
84 | bss->has_erp_value = 1; | |
85 | } | |
86 | ||
5484e237 JB |
87 | if (elems->tim) { |
88 | struct ieee80211_tim_ie *tim_ie = | |
89 | (struct ieee80211_tim_ie *)elems->tim; | |
90 | bss->dtim_period = tim_ie->dtim_period; | |
91 | } | |
92 | ||
93 | /* set default value for buggy APs */ | |
94 | if (!elems->tim || bss->dtim_period == 0) | |
95 | bss->dtim_period = 1; | |
96 | ||
97 | bss->supp_rates_len = 0; | |
98 | if (elems->supp_rates) { | |
99 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
100 | if (clen > elems->supp_rates_len) | |
101 | clen = elems->supp_rates_len; | |
102 | memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, | |
103 | clen); | |
104 | bss->supp_rates_len += clen; | |
105 | } | |
106 | if (elems->ext_supp_rates) { | |
107 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
108 | if (clen > elems->ext_supp_rates_len) | |
109 | clen = elems->ext_supp_rates_len; | |
110 | memcpy(&bss->supp_rates[bss->supp_rates_len], | |
111 | elems->ext_supp_rates, clen); | |
112 | bss->supp_rates_len += clen; | |
113 | } | |
114 | ||
5484e237 JB |
115 | bss->wmm_used = elems->wmm_param || elems->wmm_info; |
116 | ||
117 | if (!beacon) | |
118 | bss->last_probe_resp = jiffies; | |
119 | ||
5484e237 JB |
120 | return bss; |
121 | } | |
0a51b27e | 122 | |
98c8fccf | 123 | ieee80211_rx_result |
f1d58c25 | 124 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 125 | { |
f1d58c25 | 126 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 127 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 128 | struct ieee80211_bss *bss; |
98c8fccf JB |
129 | u8 *elements; |
130 | struct ieee80211_channel *channel; | |
131 | size_t baselen; | |
132 | int freq; | |
133 | __le16 fc; | |
134 | bool presp, beacon = false; | |
135 | struct ieee802_11_elems elems; | |
136 | ||
137 | if (skb->len < 2) | |
138 | return RX_DROP_UNUSABLE; | |
139 | ||
140 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
141 | fc = mgmt->frame_control; | |
142 | ||
143 | if (ieee80211_is_ctl(fc)) | |
144 | return RX_CONTINUE; | |
145 | ||
146 | if (skb->len < 24) | |
147 | return RX_DROP_MONITOR; | |
148 | ||
149 | presp = ieee80211_is_probe_resp(fc); | |
150 | if (presp) { | |
151 | /* ignore ProbeResp to foreign address */ | |
152 | if (memcmp(mgmt->da, sdata->dev->dev_addr, ETH_ALEN)) | |
153 | return RX_DROP_MONITOR; | |
154 | ||
155 | presp = true; | |
156 | elements = mgmt->u.probe_resp.variable; | |
157 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
158 | } else { | |
159 | beacon = ieee80211_is_beacon(fc); | |
160 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
161 | elements = mgmt->u.beacon.variable; | |
162 | } | |
163 | ||
164 | if (!presp && !beacon) | |
165 | return RX_CONTINUE; | |
166 | ||
167 | if (baselen > skb->len) | |
168 | return RX_DROP_MONITOR; | |
169 | ||
170 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
171 | ||
172 | if (elems.ds_params && elems.ds_params_len == 1) | |
173 | freq = ieee80211_channel_to_frequency(elems.ds_params[0]); | |
174 | else | |
175 | freq = rx_status->freq; | |
176 | ||
177 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
178 | ||
179 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
180 | return RX_DROP_MONITOR; | |
181 | ||
182 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
183 | mgmt, skb->len, &elems, | |
2a519311 | 184 | channel, beacon); |
d048e503 JM |
185 | if (bss) |
186 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf JB |
187 | |
188 | dev_kfree_skb(skb); | |
189 | return RX_QUEUED; | |
190 | } | |
191 | ||
9050bdd8 KV |
192 | /* |
193 | * inform AP that we will go to sleep so that it will buffer the frames | |
194 | * while we scan | |
195 | */ | |
196 | static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) | |
197 | { | |
198 | struct ieee80211_local *local = sdata->local; | |
199 | bool ps = false; | |
200 | ||
201 | /* FIXME: what to do when local->pspolling is true? */ | |
202 | ||
203 | del_timer_sync(&local->dynamic_ps_timer); | |
204 | cancel_work_sync(&local->dynamic_ps_enable_work); | |
205 | ||
206 | if (local->hw.conf.flags & IEEE80211_CONF_PS) { | |
207 | ps = true; | |
208 | local->hw.conf.flags &= ~IEEE80211_CONF_PS; | |
209 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
210 | } | |
211 | ||
212 | if (!ps || !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) | |
213 | /* | |
214 | * If power save was enabled, no need to send a nullfunc | |
215 | * frame because AP knows that we are sleeping. But if the | |
216 | * hardware is creating the nullfunc frame for power save | |
217 | * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not | |
218 | * enabled) and power save was enabled, the firmware just | |
219 | * sent a null frame with power save disabled. So we need | |
220 | * to send a new nullfunc frame to inform the AP that we | |
221 | * are again sleeping. | |
222 | */ | |
223 | ieee80211_send_nullfunc(local, sdata, 1); | |
224 | } | |
225 | ||
226 | /* inform AP that we are awake again, unless power save is enabled */ | |
227 | static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) | |
228 | { | |
229 | struct ieee80211_local *local = sdata->local; | |
230 | ||
965bedad | 231 | if (!local->ps_sdata) |
9050bdd8 KV |
232 | ieee80211_send_nullfunc(local, sdata, 0); |
233 | else { | |
234 | /* | |
235 | * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware | |
236 | * will send a nullfunc frame with the powersave bit set | |
237 | * even though the AP already knows that we are sleeping. | |
238 | * This could be avoided by sending a null frame with power | |
239 | * save bit disabled before enabling the power save, but | |
240 | * this doesn't gain anything. | |
241 | * | |
242 | * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need | |
243 | * to send a nullfunc frame because AP already knows that | |
244 | * we are sleeping, let's just enable power save mode in | |
245 | * hardware. | |
246 | */ | |
247 | local->hw.conf.flags |= IEEE80211_CONF_PS; | |
248 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
249 | } | |
250 | } | |
251 | ||
f3b85252 JB |
252 | static void ieee80211_restore_scan_ies(struct ieee80211_local *local) |
253 | { | |
254 | kfree(local->scan_req->ie); | |
255 | local->scan_req->ie = local->orig_ies; | |
256 | local->scan_req->ie_len = local->orig_ies_len; | |
257 | } | |
258 | ||
2a519311 | 259 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) |
0a51b27e JB |
260 | { |
261 | struct ieee80211_local *local = hw_to_local(hw); | |
262 | struct ieee80211_sub_if_data *sdata; | |
f3b85252 | 263 | bool was_hw_scan; |
0a51b27e | 264 | |
f3b85252 | 265 | mutex_lock(&local->scan_mtx); |
5bc75728 | 266 | |
fbe9c429 | 267 | if (WARN_ON(!local->scanning)) { |
f3b85252 | 268 | mutex_unlock(&local->scan_mtx); |
2a519311 | 269 | return; |
f3b85252 | 270 | } |
5bc75728 | 271 | |
f3b85252 JB |
272 | if (WARN_ON(!local->scan_req)) { |
273 | mutex_unlock(&local->scan_mtx); | |
274 | return; | |
de95a54b JB |
275 | } |
276 | ||
fbe9c429 | 277 | if (test_bit(SCAN_HW_SCANNING, &local->scanning)) |
f3b85252 JB |
278 | ieee80211_restore_scan_ies(local); |
279 | ||
5ba63533 | 280 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
281 | cfg80211_scan_done(local->scan_req, aborted); |
282 | local->scan_req = NULL; | |
15db0b7f | 283 | local->scan_sdata = NULL; |
2a519311 | 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 | |
3ac64bee | 296 | ieee80211_configure_filter(local); |
0a51b27e | 297 | |
24487981 | 298 | drv_sw_scan_complete(local); |
80e775bf | 299 | |
078e1e60 JB |
300 | mutex_lock(&local->iflist_mtx); |
301 | list_for_each_entry(sdata, &local->interfaces, list) { | |
fb9ddbf0 JB |
302 | if (!netif_running(sdata->dev)) |
303 | continue; | |
304 | ||
0a51b27e | 305 | /* Tell AP we're back */ |
05c914fe | 306 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
77fdaa12 | 307 | if (sdata->u.mgd.associated) { |
9050bdd8 | 308 | ieee80211_scan_ps_disable(sdata); |
0a51b27e JB |
309 | netif_tx_wake_all_queues(sdata->dev); |
310 | } | |
311 | } else | |
312 | netif_tx_wake_all_queues(sdata->dev); | |
078e1e60 | 313 | |
14b80724 JB |
314 | /* re-enable beaconing */ |
315 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
316 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
317 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
318 | ieee80211_bss_info_change_notify( |
319 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
0a51b27e | 320 | } |
078e1e60 | 321 | mutex_unlock(&local->iflist_mtx); |
0a51b27e JB |
322 | |
323 | done: | |
5cff20e6 | 324 | ieee80211_recalc_idle(local); |
0a51b27e | 325 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 326 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 327 | ieee80211_mesh_notify_scan_completed(local); |
0a51b27e JB |
328 | } |
329 | EXPORT_SYMBOL(ieee80211_scan_completed); | |
330 | ||
f3b85252 JB |
331 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
332 | { | |
333 | struct ieee80211_sub_if_data *sdata; | |
334 | ||
335 | /* | |
336 | * Hardware/driver doesn't support hw_scan, so use software | |
337 | * scanning instead. First send a nullfunc frame with power save | |
338 | * bit on so that AP will buffer the frames for us while we are not | |
339 | * listening, then send probe requests to each channel and wait for | |
340 | * the responses. After all channels are scanned, tune back to the | |
341 | * original channel and send a nullfunc frame with power save bit | |
342 | * off to trigger the AP to send us all the buffered frames. | |
343 | * | |
344 | * Note that while local->sw_scanning is true everything else but | |
345 | * nullfunc frames and probe requests will be dropped in | |
346 | * ieee80211_tx_h_check_assoc(). | |
347 | */ | |
24487981 | 348 | drv_sw_scan_start(local); |
f3b85252 JB |
349 | |
350 | mutex_lock(&local->iflist_mtx); | |
351 | list_for_each_entry(sdata, &local->interfaces, list) { | |
352 | if (!netif_running(sdata->dev)) | |
353 | continue; | |
354 | ||
355 | /* disable beaconing */ | |
356 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
357 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
358 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
359 | ieee80211_bss_info_change_notify( |
360 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
f3b85252 | 361 | |
142b9f50 HS |
362 | /* |
363 | * only handle non-STA interfaces here, STA interfaces | |
364 | * are handled in the scan state machine | |
365 | */ | |
366 | if (sdata->vif.type != NL80211_IFTYPE_STATION) | |
f3b85252 JB |
367 | netif_tx_stop_all_queues(sdata->dev); |
368 | } | |
369 | mutex_unlock(&local->iflist_mtx); | |
370 | ||
977923b0 | 371 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
372 | local->scan_channel_idx = 0; |
373 | ||
3ac64bee | 374 | ieee80211_configure_filter(local); |
f3b85252 JB |
375 | |
376 | /* TODO: start scan as soon as all nullfunc frames are ACKed */ | |
42935eca LR |
377 | ieee80211_queue_delayed_work(&local->hw, |
378 | &local->scan_work, | |
379 | IEEE80211_CHANNEL_TIME); | |
f3b85252 JB |
380 | |
381 | return 0; | |
382 | } | |
383 | ||
384 | ||
385 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
386 | struct cfg80211_scan_request *req) | |
387 | { | |
388 | struct ieee80211_local *local = sdata->local; | |
389 | struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; | |
390 | int rc; | |
391 | ||
392 | if (local->scan_req) | |
393 | return -EBUSY; | |
394 | ||
395 | if (local->ops->hw_scan) { | |
396 | u8 *ies; | |
397 | int ielen; | |
398 | ||
399 | ies = kmalloc(2 + IEEE80211_MAX_SSID_LEN + | |
400 | local->scan_ies_len + req->ie_len, GFP_KERNEL); | |
401 | if (!ies) | |
402 | return -ENOMEM; | |
403 | ||
404 | ielen = ieee80211_build_preq_ies(local, ies, | |
405 | req->ie, req->ie_len); | |
406 | local->orig_ies = req->ie; | |
407 | local->orig_ies_len = req->ie_len; | |
408 | req->ie = ies; | |
409 | req->ie_len = ielen; | |
410 | } | |
411 | ||
412 | local->scan_req = req; | |
413 | local->scan_sdata = sdata; | |
414 | ||
5ba63533 | 415 | if (req != local->int_scan_req && |
f3b85252 | 416 | sdata->vif.type == NL80211_IFTYPE_STATION && |
77fdaa12 JB |
417 | !list_empty(&ifmgd->work_list)) { |
418 | /* actually wait for the work it's doing to finish/time out */ | |
f3b85252 JB |
419 | set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request); |
420 | return 0; | |
421 | } | |
422 | ||
423 | if (local->ops->hw_scan) | |
fbe9c429 | 424 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 425 | else |
fbe9c429 | 426 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
f3b85252 JB |
427 | /* |
428 | * Kicking off the scan need not be protected, | |
429 | * only the scan variable stuff, since now | |
430 | * local->scan_req is assigned and other callers | |
431 | * will abort their scan attempts. | |
432 | * | |
433 | * This avoids getting a scan_mtx -> iflist_mtx | |
434 | * dependency, so that the scan completed calls | |
435 | * have more locking freedom. | |
436 | */ | |
5cff20e6 JB |
437 | |
438 | ieee80211_recalc_idle(local); | |
f3b85252 JB |
439 | mutex_unlock(&local->scan_mtx); |
440 | ||
441 | if (local->ops->hw_scan) | |
24487981 | 442 | rc = drv_hw_scan(local, local->scan_req); |
f3b85252 JB |
443 | else |
444 | rc = ieee80211_start_sw_scan(local); | |
445 | ||
446 | mutex_lock(&local->scan_mtx); | |
447 | ||
448 | if (rc) { | |
fbe9c429 | 449 | if (local->ops->hw_scan) |
f3b85252 | 450 | ieee80211_restore_scan_ies(local); |
fbe9c429 | 451 | local->scanning = 0; |
f3b85252 | 452 | |
5cff20e6 JB |
453 | ieee80211_recalc_idle(local); |
454 | ||
f3b85252 JB |
455 | local->scan_req = NULL; |
456 | local->scan_sdata = NULL; | |
457 | } | |
458 | ||
459 | return rc; | |
460 | } | |
461 | ||
2fb3f028 HS |
462 | static int ieee80211_scan_state_decision(struct ieee80211_local *local, |
463 | unsigned long *next_delay) | |
7d3be3cc | 464 | { |
142b9f50 HS |
465 | bool associated = false; |
466 | struct ieee80211_sub_if_data *sdata; | |
467 | ||
468 | /* if no more bands/channels left, complete scan and advance to the idle state */ | |
7d3be3cc HS |
469 | if (local->scan_channel_idx >= local->scan_req->n_channels) { |
470 | ieee80211_scan_completed(&local->hw, false); | |
471 | return 1; | |
472 | } | |
2fb3f028 | 473 | |
142b9f50 HS |
474 | /* check if at least one STA interface is associated */ |
475 | mutex_lock(&local->iflist_mtx); | |
476 | list_for_each_entry(sdata, &local->interfaces, list) { | |
477 | if (!netif_running(sdata->dev)) | |
478 | continue; | |
479 | ||
480 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
481 | if (sdata->u.mgd.associated) { | |
482 | associated = true; | |
483 | break; | |
484 | } | |
485 | } | |
486 | } | |
487 | mutex_unlock(&local->iflist_mtx); | |
488 | ||
489 | if (local->scan_channel) { | |
490 | /* | |
491 | * we're currently scanning a different channel, let's | |
492 | * switch back to the operating channel now if at least | |
493 | * one interface is associated. Otherwise just scan the | |
494 | * next channel | |
495 | */ | |
496 | if (associated) | |
977923b0 | 497 | local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; |
142b9f50 | 498 | else |
977923b0 | 499 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
500 | } else { |
501 | /* | |
502 | * we're on the operating channel currently, let's | |
503 | * leave that channel now to scan another one | |
504 | */ | |
977923b0 | 505 | local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; |
142b9f50 HS |
506 | } |
507 | ||
2fb3f028 | 508 | *next_delay = 0; |
2fb3f028 HS |
509 | return 0; |
510 | } | |
511 | ||
142b9f50 HS |
512 | static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, |
513 | unsigned long *next_delay) | |
514 | { | |
515 | struct ieee80211_sub_if_data *sdata; | |
516 | ||
517 | /* | |
518 | * notify the AP about us leaving the channel and stop all STA interfaces | |
519 | */ | |
520 | mutex_lock(&local->iflist_mtx); | |
521 | list_for_each_entry(sdata, &local->interfaces, list) { | |
522 | if (!netif_running(sdata->dev)) | |
523 | continue; | |
524 | ||
525 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
526 | netif_tx_stop_all_queues(sdata->dev); | |
527 | if (sdata->u.mgd.associated) | |
528 | ieee80211_scan_ps_enable(sdata); | |
529 | } | |
530 | } | |
531 | mutex_unlock(&local->iflist_mtx); | |
532 | ||
533 | __set_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
534 | ||
535 | /* advance to the next channel to be scanned */ | |
536 | *next_delay = HZ / 10; | |
977923b0 | 537 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
538 | } |
539 | ||
540 | static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, | |
541 | unsigned long *next_delay) | |
542 | { | |
543 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
544 | ||
545 | /* switch back to the operating channel */ | |
546 | local->scan_channel = NULL; | |
547 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
548 | ||
549 | /* | |
550 | * notify the AP about us being back and restart all STA interfaces | |
551 | */ | |
552 | mutex_lock(&local->iflist_mtx); | |
553 | list_for_each_entry(sdata, &local->interfaces, list) { | |
554 | if (!netif_running(sdata->dev)) | |
555 | continue; | |
556 | ||
557 | /* Tell AP we're back */ | |
558 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
559 | if (sdata->u.mgd.associated) | |
560 | ieee80211_scan_ps_disable(sdata); | |
561 | netif_tx_wake_all_queues(sdata->dev); | |
562 | } | |
563 | } | |
564 | mutex_unlock(&local->iflist_mtx); | |
565 | ||
566 | __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
567 | ||
568 | *next_delay = HZ / 5; | |
977923b0 | 569 | local->next_scan_state = SCAN_DECISION; |
142b9f50 HS |
570 | } |
571 | ||
2fb3f028 HS |
572 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
573 | unsigned long *next_delay) | |
574 | { | |
575 | int skip; | |
576 | struct ieee80211_channel *chan; | |
577 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
578 | ||
7d3be3cc HS |
579 | skip = 0; |
580 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
581 | ||
582 | if (chan->flags & IEEE80211_CHAN_DISABLED || | |
583 | (sdata->vif.type == NL80211_IFTYPE_ADHOC && | |
584 | chan->flags & IEEE80211_CHAN_NO_IBSS)) | |
585 | skip = 1; | |
586 | ||
587 | if (!skip) { | |
588 | local->scan_channel = chan; | |
589 | if (ieee80211_hw_config(local, | |
590 | IEEE80211_CONF_CHANGE_CHANNEL)) | |
591 | skip = 1; | |
592 | } | |
593 | ||
594 | /* advance state machine to next channel/band */ | |
595 | local->scan_channel_idx++; | |
596 | ||
0ee9c13c HS |
597 | if (skip) { |
598 | /* if we skip this channel return to the decision state */ | |
599 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 600 | return; |
0ee9c13c | 601 | } |
7d3be3cc HS |
602 | |
603 | /* | |
604 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
605 | * (which unfortunately doesn't say _why_ step a) is done, | |
606 | * but it waits for the probe delay or until a frame is | |
607 | * received - and the received frame would update the NAV). | |
608 | * For now, we do not support waiting until a frame is | |
609 | * received. | |
610 | * | |
611 | * In any case, it is not necessary for a passive scan. | |
612 | */ | |
613 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
614 | !local->scan_req->n_ssids) { | |
615 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 616 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 617 | return; |
7d3be3cc HS |
618 | } |
619 | ||
2fb3f028 | 620 | /* active scan, send probes */ |
7d3be3cc | 621 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 622 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
623 | } |
624 | ||
625 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
626 | unsigned long *next_delay) | |
627 | { | |
628 | int i; | |
629 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
630 | ||
631 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
632 | ieee80211_send_probe_req( | |
633 | sdata, NULL, | |
634 | local->scan_req->ssids[i].ssid, | |
635 | local->scan_req->ssids[i].ssid_len, | |
636 | local->scan_req->ie, local->scan_req->ie_len); | |
637 | ||
638 | /* | |
639 | * After sending probe requests, wait for probe responses | |
640 | * on the channel. | |
641 | */ | |
642 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 643 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
644 | } |
645 | ||
c2b13452 | 646 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
647 | { |
648 | struct ieee80211_local *local = | |
649 | container_of(work, struct ieee80211_local, scan_work.work); | |
650 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
0a51b27e JB |
651 | unsigned long next_delay = 0; |
652 | ||
f3b85252 JB |
653 | mutex_lock(&local->scan_mtx); |
654 | if (!sdata || !local->scan_req) { | |
655 | mutex_unlock(&local->scan_mtx); | |
656 | return; | |
657 | } | |
658 | ||
fbe9c429 | 659 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
660 | struct cfg80211_scan_request *req = local->scan_req; |
661 | int rc; | |
662 | ||
663 | local->scan_req = NULL; | |
15db0b7f | 664 | local->scan_sdata = NULL; |
f3b85252 JB |
665 | |
666 | rc = __ieee80211_start_scan(sdata, req); | |
667 | mutex_unlock(&local->scan_mtx); | |
668 | ||
669 | if (rc) | |
670 | ieee80211_scan_completed(&local->hw, true); | |
671 | return; | |
672 | } | |
673 | ||
674 | mutex_unlock(&local->scan_mtx); | |
675 | ||
5bc75728 JB |
676 | /* |
677 | * Avoid re-scheduling when the sdata is going away. | |
678 | */ | |
f3b85252 JB |
679 | if (!netif_running(sdata->dev)) { |
680 | ieee80211_scan_completed(&local->hw, true); | |
0a51b27e | 681 | return; |
f3b85252 | 682 | } |
0a51b27e | 683 | |
f502d09b HS |
684 | /* |
685 | * as long as no delay is required advance immediately | |
686 | * without scheduling a new work | |
687 | */ | |
688 | do { | |
977923b0 | 689 | switch (local->next_scan_state) { |
2fb3f028 HS |
690 | case SCAN_DECISION: |
691 | if (ieee80211_scan_state_decision(local, &next_delay)) | |
f502d09b HS |
692 | return; |
693 | break; | |
2fb3f028 HS |
694 | case SCAN_SET_CHANNEL: |
695 | ieee80211_scan_state_set_channel(local, &next_delay); | |
696 | break; | |
f502d09b HS |
697 | case SCAN_SEND_PROBE: |
698 | ieee80211_scan_state_send_probe(local, &next_delay); | |
699 | break; | |
142b9f50 HS |
700 | case SCAN_LEAVE_OPER_CHANNEL: |
701 | ieee80211_scan_state_leave_oper_channel(local, &next_delay); | |
702 | break; | |
703 | case SCAN_ENTER_OPER_CHANNEL: | |
704 | ieee80211_scan_state_enter_oper_channel(local, &next_delay); | |
705 | break; | |
f502d09b HS |
706 | } |
707 | } while (next_delay == 0); | |
0a51b27e | 708 | |
42935eca | 709 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
0a51b27e JB |
710 | } |
711 | ||
f3b85252 JB |
712 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
713 | struct cfg80211_scan_request *req) | |
0a51b27e | 714 | { |
f3b85252 | 715 | int res; |
de95a54b | 716 | |
f3b85252 JB |
717 | mutex_lock(&sdata->local->scan_mtx); |
718 | res = __ieee80211_start_scan(sdata, req); | |
719 | mutex_unlock(&sdata->local->scan_mtx); | |
0a51b27e | 720 | |
f3b85252 | 721 | return res; |
0a51b27e JB |
722 | } |
723 | ||
f3b85252 JB |
724 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
725 | const u8 *ssid, u8 ssid_len) | |
0a51b27e | 726 | { |
0a51b27e | 727 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 728 | int ret = -EBUSY; |
2a519311 | 729 | |
f3b85252 | 730 | mutex_lock(&local->scan_mtx); |
0a51b27e | 731 | |
f3b85252 JB |
732 | /* busy scanning */ |
733 | if (local->scan_req) | |
734 | goto unlock; | |
9116dd01 | 735 | |
5ba63533 JB |
736 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
737 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 738 | |
5ba63533 | 739 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 JB |
740 | unlock: |
741 | mutex_unlock(&local->scan_mtx); | |
742 | return ret; | |
0a51b27e | 743 | } |
5bb644a0 JB |
744 | |
745 | void ieee80211_scan_cancel(struct ieee80211_local *local) | |
746 | { | |
15db0b7f | 747 | bool abortscan; |
5bb644a0 JB |
748 | |
749 | cancel_delayed_work_sync(&local->scan_work); | |
750 | ||
751 | /* | |
752 | * Only call this function when a scan can't be | |
753 | * queued -- mostly at suspend under RTNL. | |
754 | */ | |
755 | mutex_lock(&local->scan_mtx); | |
15db0b7f JB |
756 | abortscan = test_bit(SCAN_SW_SCANNING, &local->scanning) || |
757 | (!local->scanning && local->scan_req); | |
5bb644a0 JB |
758 | mutex_unlock(&local->scan_mtx); |
759 | ||
15db0b7f | 760 | if (abortscan) |
5bb644a0 JB |
761 | ieee80211_scan_completed(&local->hw, true); |
762 | } |