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 | ||
2a519311 JB |
280 | if (local->scan_req != &local->int_scan_req) |
281 | cfg80211_scan_done(local->scan_req, aborted); | |
282 | local->scan_req = NULL; | |
283 | ||
fbe9c429 HS |
284 | was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
285 | local->scanning = 0; | |
58905ca5 | 286 | local->scan_channel = NULL; |
f3b85252 JB |
287 | |
288 | /* we only have to protect scan_req and hw/sw scan */ | |
289 | mutex_unlock(&local->scan_mtx); | |
290 | ||
e8975581 | 291 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); |
5cff20e6 JB |
292 | if (was_hw_scan) |
293 | goto done; | |
0a51b27e | 294 | |
3b8d81e0 | 295 | spin_lock_bh(&local->filter_lock); |
0a51b27e | 296 | local->filter_flags &= ~FIF_BCN_PRBRESP_PROMISC; |
24487981 JB |
297 | drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC, |
298 | &local->filter_flags, | |
3b8d81e0 JB |
299 | local->mc_count, |
300 | local->mc_list); | |
301 | spin_unlock_bh(&local->filter_lock); | |
0a51b27e | 302 | |
24487981 | 303 | drv_sw_scan_complete(local); |
80e775bf | 304 | |
078e1e60 JB |
305 | mutex_lock(&local->iflist_mtx); |
306 | list_for_each_entry(sdata, &local->interfaces, list) { | |
fb9ddbf0 JB |
307 | if (!netif_running(sdata->dev)) |
308 | continue; | |
309 | ||
0a51b27e | 310 | /* Tell AP we're back */ |
05c914fe | 311 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
77fdaa12 | 312 | if (sdata->u.mgd.associated) { |
9050bdd8 | 313 | ieee80211_scan_ps_disable(sdata); |
0a51b27e JB |
314 | netif_tx_wake_all_queues(sdata->dev); |
315 | } | |
316 | } else | |
317 | netif_tx_wake_all_queues(sdata->dev); | |
078e1e60 | 318 | |
14b80724 JB |
319 | /* re-enable beaconing */ |
320 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
321 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
322 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
323 | ieee80211_bss_info_change_notify( |
324 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
0a51b27e | 325 | } |
078e1e60 | 326 | mutex_unlock(&local->iflist_mtx); |
0a51b27e JB |
327 | |
328 | done: | |
5cff20e6 | 329 | ieee80211_recalc_idle(local); |
0a51b27e | 330 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 331 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 332 | ieee80211_mesh_notify_scan_completed(local); |
0a51b27e JB |
333 | } |
334 | EXPORT_SYMBOL(ieee80211_scan_completed); | |
335 | ||
f3b85252 JB |
336 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
337 | { | |
338 | struct ieee80211_sub_if_data *sdata; | |
339 | ||
340 | /* | |
341 | * Hardware/driver doesn't support hw_scan, so use software | |
342 | * scanning instead. First send a nullfunc frame with power save | |
343 | * bit on so that AP will buffer the frames for us while we are not | |
344 | * listening, then send probe requests to each channel and wait for | |
345 | * the responses. After all channels are scanned, tune back to the | |
346 | * original channel and send a nullfunc frame with power save bit | |
347 | * off to trigger the AP to send us all the buffered frames. | |
348 | * | |
349 | * Note that while local->sw_scanning is true everything else but | |
350 | * nullfunc frames and probe requests will be dropped in | |
351 | * ieee80211_tx_h_check_assoc(). | |
352 | */ | |
24487981 | 353 | drv_sw_scan_start(local); |
f3b85252 JB |
354 | |
355 | mutex_lock(&local->iflist_mtx); | |
356 | list_for_each_entry(sdata, &local->interfaces, list) { | |
357 | if (!netif_running(sdata->dev)) | |
358 | continue; | |
359 | ||
360 | /* disable beaconing */ | |
361 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
362 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
363 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
364 | ieee80211_bss_info_change_notify( |
365 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
f3b85252 | 366 | |
142b9f50 HS |
367 | /* |
368 | * only handle non-STA interfaces here, STA interfaces | |
369 | * are handled in the scan state machine | |
370 | */ | |
371 | if (sdata->vif.type != NL80211_IFTYPE_STATION) | |
f3b85252 JB |
372 | netif_tx_stop_all_queues(sdata->dev); |
373 | } | |
374 | mutex_unlock(&local->iflist_mtx); | |
375 | ||
977923b0 | 376 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
377 | local->scan_channel_idx = 0; |
378 | ||
3b8d81e0 | 379 | spin_lock_bh(&local->filter_lock); |
f3b85252 | 380 | local->filter_flags |= FIF_BCN_PRBRESP_PROMISC; |
24487981 JB |
381 | drv_configure_filter(local, FIF_BCN_PRBRESP_PROMISC, |
382 | &local->filter_flags, | |
3b8d81e0 JB |
383 | local->mc_count, |
384 | local->mc_list); | |
385 | spin_unlock_bh(&local->filter_lock); | |
f3b85252 JB |
386 | |
387 | /* TODO: start scan as soon as all nullfunc frames are ACKed */ | |
388 | queue_delayed_work(local->hw.workqueue, &local->scan_work, | |
389 | IEEE80211_CHANNEL_TIME); | |
390 | ||
391 | return 0; | |
392 | } | |
393 | ||
394 | ||
395 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
396 | struct cfg80211_scan_request *req) | |
397 | { | |
398 | struct ieee80211_local *local = sdata->local; | |
399 | struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; | |
400 | int rc; | |
401 | ||
402 | if (local->scan_req) | |
403 | return -EBUSY; | |
404 | ||
405 | if (local->ops->hw_scan) { | |
406 | u8 *ies; | |
407 | int ielen; | |
408 | ||
409 | ies = kmalloc(2 + IEEE80211_MAX_SSID_LEN + | |
410 | local->scan_ies_len + req->ie_len, GFP_KERNEL); | |
411 | if (!ies) | |
412 | return -ENOMEM; | |
413 | ||
414 | ielen = ieee80211_build_preq_ies(local, ies, | |
415 | req->ie, req->ie_len); | |
416 | local->orig_ies = req->ie; | |
417 | local->orig_ies_len = req->ie_len; | |
418 | req->ie = ies; | |
419 | req->ie_len = ielen; | |
420 | } | |
421 | ||
422 | local->scan_req = req; | |
423 | local->scan_sdata = sdata; | |
424 | ||
425 | if (req != &local->int_scan_req && | |
426 | sdata->vif.type == NL80211_IFTYPE_STATION && | |
77fdaa12 JB |
427 | !list_empty(&ifmgd->work_list)) { |
428 | /* actually wait for the work it's doing to finish/time out */ | |
f3b85252 JB |
429 | set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request); |
430 | return 0; | |
431 | } | |
432 | ||
433 | if (local->ops->hw_scan) | |
fbe9c429 | 434 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 435 | else |
fbe9c429 | 436 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
f3b85252 JB |
437 | /* |
438 | * Kicking off the scan need not be protected, | |
439 | * only the scan variable stuff, since now | |
440 | * local->scan_req is assigned and other callers | |
441 | * will abort their scan attempts. | |
442 | * | |
443 | * This avoids getting a scan_mtx -> iflist_mtx | |
444 | * dependency, so that the scan completed calls | |
445 | * have more locking freedom. | |
446 | */ | |
5cff20e6 JB |
447 | |
448 | ieee80211_recalc_idle(local); | |
f3b85252 JB |
449 | mutex_unlock(&local->scan_mtx); |
450 | ||
451 | if (local->ops->hw_scan) | |
24487981 | 452 | rc = drv_hw_scan(local, local->scan_req); |
f3b85252 JB |
453 | else |
454 | rc = ieee80211_start_sw_scan(local); | |
455 | ||
456 | mutex_lock(&local->scan_mtx); | |
457 | ||
458 | if (rc) { | |
fbe9c429 | 459 | if (local->ops->hw_scan) |
f3b85252 | 460 | ieee80211_restore_scan_ies(local); |
fbe9c429 | 461 | local->scanning = 0; |
f3b85252 | 462 | |
5cff20e6 JB |
463 | ieee80211_recalc_idle(local); |
464 | ||
f3b85252 JB |
465 | local->scan_req = NULL; |
466 | local->scan_sdata = NULL; | |
467 | } | |
468 | ||
469 | return rc; | |
470 | } | |
471 | ||
2fb3f028 HS |
472 | static int ieee80211_scan_state_decision(struct ieee80211_local *local, |
473 | unsigned long *next_delay) | |
7d3be3cc | 474 | { |
142b9f50 HS |
475 | bool associated = false; |
476 | struct ieee80211_sub_if_data *sdata; | |
477 | ||
478 | /* if no more bands/channels left, complete scan and advance to the idle state */ | |
7d3be3cc HS |
479 | if (local->scan_channel_idx >= local->scan_req->n_channels) { |
480 | ieee80211_scan_completed(&local->hw, false); | |
481 | return 1; | |
482 | } | |
2fb3f028 | 483 | |
142b9f50 HS |
484 | /* check if at least one STA interface is associated */ |
485 | mutex_lock(&local->iflist_mtx); | |
486 | list_for_each_entry(sdata, &local->interfaces, list) { | |
487 | if (!netif_running(sdata->dev)) | |
488 | continue; | |
489 | ||
490 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
491 | if (sdata->u.mgd.associated) { | |
492 | associated = true; | |
493 | break; | |
494 | } | |
495 | } | |
496 | } | |
497 | mutex_unlock(&local->iflist_mtx); | |
498 | ||
499 | if (local->scan_channel) { | |
500 | /* | |
501 | * we're currently scanning a different channel, let's | |
502 | * switch back to the operating channel now if at least | |
503 | * one interface is associated. Otherwise just scan the | |
504 | * next channel | |
505 | */ | |
506 | if (associated) | |
977923b0 | 507 | local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; |
142b9f50 | 508 | else |
977923b0 | 509 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
510 | } else { |
511 | /* | |
512 | * we're on the operating channel currently, let's | |
513 | * leave that channel now to scan another one | |
514 | */ | |
977923b0 | 515 | local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; |
142b9f50 HS |
516 | } |
517 | ||
2fb3f028 | 518 | *next_delay = 0; |
2fb3f028 HS |
519 | return 0; |
520 | } | |
521 | ||
142b9f50 HS |
522 | static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, |
523 | unsigned long *next_delay) | |
524 | { | |
525 | struct ieee80211_sub_if_data *sdata; | |
526 | ||
527 | /* | |
528 | * notify the AP about us leaving the channel and stop all STA interfaces | |
529 | */ | |
530 | mutex_lock(&local->iflist_mtx); | |
531 | list_for_each_entry(sdata, &local->interfaces, list) { | |
532 | if (!netif_running(sdata->dev)) | |
533 | continue; | |
534 | ||
535 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
536 | netif_tx_stop_all_queues(sdata->dev); | |
537 | if (sdata->u.mgd.associated) | |
538 | ieee80211_scan_ps_enable(sdata); | |
539 | } | |
540 | } | |
541 | mutex_unlock(&local->iflist_mtx); | |
542 | ||
543 | __set_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
544 | ||
545 | /* advance to the next channel to be scanned */ | |
546 | *next_delay = HZ / 10; | |
977923b0 | 547 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
548 | } |
549 | ||
550 | static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, | |
551 | unsigned long *next_delay) | |
552 | { | |
553 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
554 | ||
555 | /* switch back to the operating channel */ | |
556 | local->scan_channel = NULL; | |
557 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
558 | ||
559 | /* | |
560 | * notify the AP about us being back and restart all STA interfaces | |
561 | */ | |
562 | mutex_lock(&local->iflist_mtx); | |
563 | list_for_each_entry(sdata, &local->interfaces, list) { | |
564 | if (!netif_running(sdata->dev)) | |
565 | continue; | |
566 | ||
567 | /* Tell AP we're back */ | |
568 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
569 | if (sdata->u.mgd.associated) | |
570 | ieee80211_scan_ps_disable(sdata); | |
571 | netif_tx_wake_all_queues(sdata->dev); | |
572 | } | |
573 | } | |
574 | mutex_unlock(&local->iflist_mtx); | |
575 | ||
576 | __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
577 | ||
578 | *next_delay = HZ / 5; | |
977923b0 | 579 | local->next_scan_state = SCAN_DECISION; |
142b9f50 HS |
580 | } |
581 | ||
2fb3f028 HS |
582 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
583 | unsigned long *next_delay) | |
584 | { | |
585 | int skip; | |
586 | struct ieee80211_channel *chan; | |
587 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
588 | ||
7d3be3cc HS |
589 | skip = 0; |
590 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
591 | ||
592 | if (chan->flags & IEEE80211_CHAN_DISABLED || | |
593 | (sdata->vif.type == NL80211_IFTYPE_ADHOC && | |
594 | chan->flags & IEEE80211_CHAN_NO_IBSS)) | |
595 | skip = 1; | |
596 | ||
597 | if (!skip) { | |
598 | local->scan_channel = chan; | |
599 | if (ieee80211_hw_config(local, | |
600 | IEEE80211_CONF_CHANGE_CHANNEL)) | |
601 | skip = 1; | |
602 | } | |
603 | ||
604 | /* advance state machine to next channel/band */ | |
605 | local->scan_channel_idx++; | |
606 | ||
0ee9c13c HS |
607 | if (skip) { |
608 | /* if we skip this channel return to the decision state */ | |
609 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 610 | return; |
0ee9c13c | 611 | } |
7d3be3cc HS |
612 | |
613 | /* | |
614 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
615 | * (which unfortunately doesn't say _why_ step a) is done, | |
616 | * but it waits for the probe delay or until a frame is | |
617 | * received - and the received frame would update the NAV). | |
618 | * For now, we do not support waiting until a frame is | |
619 | * received. | |
620 | * | |
621 | * In any case, it is not necessary for a passive scan. | |
622 | */ | |
623 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
624 | !local->scan_req->n_ssids) { | |
625 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 626 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 627 | return; |
7d3be3cc HS |
628 | } |
629 | ||
2fb3f028 | 630 | /* active scan, send probes */ |
7d3be3cc | 631 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 632 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
633 | } |
634 | ||
635 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
636 | unsigned long *next_delay) | |
637 | { | |
638 | int i; | |
639 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
640 | ||
641 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
642 | ieee80211_send_probe_req( | |
643 | sdata, NULL, | |
644 | local->scan_req->ssids[i].ssid, | |
645 | local->scan_req->ssids[i].ssid_len, | |
646 | local->scan_req->ie, local->scan_req->ie_len); | |
647 | ||
648 | /* | |
649 | * After sending probe requests, wait for probe responses | |
650 | * on the channel. | |
651 | */ | |
652 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 653 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
654 | } |
655 | ||
c2b13452 | 656 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
657 | { |
658 | struct ieee80211_local *local = | |
659 | container_of(work, struct ieee80211_local, scan_work.work); | |
660 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
0a51b27e JB |
661 | unsigned long next_delay = 0; |
662 | ||
f3b85252 JB |
663 | mutex_lock(&local->scan_mtx); |
664 | if (!sdata || !local->scan_req) { | |
665 | mutex_unlock(&local->scan_mtx); | |
666 | return; | |
667 | } | |
668 | ||
fbe9c429 | 669 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
670 | struct cfg80211_scan_request *req = local->scan_req; |
671 | int rc; | |
672 | ||
673 | local->scan_req = NULL; | |
674 | ||
675 | rc = __ieee80211_start_scan(sdata, req); | |
676 | mutex_unlock(&local->scan_mtx); | |
677 | ||
678 | if (rc) | |
679 | ieee80211_scan_completed(&local->hw, true); | |
680 | return; | |
681 | } | |
682 | ||
683 | mutex_unlock(&local->scan_mtx); | |
684 | ||
5bc75728 JB |
685 | /* |
686 | * Avoid re-scheduling when the sdata is going away. | |
687 | */ | |
f3b85252 JB |
688 | if (!netif_running(sdata->dev)) { |
689 | ieee80211_scan_completed(&local->hw, true); | |
0a51b27e | 690 | return; |
f3b85252 | 691 | } |
0a51b27e | 692 | |
f502d09b HS |
693 | /* |
694 | * as long as no delay is required advance immediately | |
695 | * without scheduling a new work | |
696 | */ | |
697 | do { | |
977923b0 | 698 | switch (local->next_scan_state) { |
2fb3f028 HS |
699 | case SCAN_DECISION: |
700 | if (ieee80211_scan_state_decision(local, &next_delay)) | |
f502d09b HS |
701 | return; |
702 | break; | |
2fb3f028 HS |
703 | case SCAN_SET_CHANNEL: |
704 | ieee80211_scan_state_set_channel(local, &next_delay); | |
705 | break; | |
f502d09b HS |
706 | case SCAN_SEND_PROBE: |
707 | ieee80211_scan_state_send_probe(local, &next_delay); | |
708 | break; | |
142b9f50 HS |
709 | case SCAN_LEAVE_OPER_CHANNEL: |
710 | ieee80211_scan_state_leave_oper_channel(local, &next_delay); | |
711 | break; | |
712 | case SCAN_ENTER_OPER_CHANNEL: | |
713 | ieee80211_scan_state_enter_oper_channel(local, &next_delay); | |
714 | break; | |
f502d09b HS |
715 | } |
716 | } while (next_delay == 0); | |
0a51b27e | 717 | |
5bc75728 JB |
718 | queue_delayed_work(local->hw.workqueue, &local->scan_work, |
719 | next_delay); | |
0a51b27e JB |
720 | } |
721 | ||
f3b85252 JB |
722 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
723 | struct cfg80211_scan_request *req) | |
0a51b27e | 724 | { |
f3b85252 | 725 | int res; |
de95a54b | 726 | |
f3b85252 JB |
727 | mutex_lock(&sdata->local->scan_mtx); |
728 | res = __ieee80211_start_scan(sdata, req); | |
729 | mutex_unlock(&sdata->local->scan_mtx); | |
0a51b27e | 730 | |
f3b85252 | 731 | return res; |
0a51b27e JB |
732 | } |
733 | ||
f3b85252 JB |
734 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
735 | const u8 *ssid, u8 ssid_len) | |
0a51b27e | 736 | { |
0a51b27e | 737 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 738 | int ret = -EBUSY; |
2a519311 | 739 | |
f3b85252 | 740 | mutex_lock(&local->scan_mtx); |
0a51b27e | 741 | |
f3b85252 JB |
742 | /* busy scanning */ |
743 | if (local->scan_req) | |
744 | goto unlock; | |
9116dd01 | 745 | |
f3b85252 JB |
746 | memcpy(local->int_scan_req.ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
747 | local->int_scan_req.ssids[0].ssid_len = ssid_len; | |
9116dd01 | 748 | |
f3b85252 JB |
749 | ret = __ieee80211_start_scan(sdata, &sdata->local->int_scan_req); |
750 | unlock: | |
751 | mutex_unlock(&local->scan_mtx); | |
752 | return ret; | |
0a51b27e | 753 | } |
5bb644a0 JB |
754 | |
755 | void ieee80211_scan_cancel(struct ieee80211_local *local) | |
756 | { | |
757 | bool swscan; | |
758 | ||
759 | cancel_delayed_work_sync(&local->scan_work); | |
760 | ||
761 | /* | |
762 | * Only call this function when a scan can't be | |
763 | * queued -- mostly at suspend under RTNL. | |
764 | */ | |
765 | mutex_lock(&local->scan_mtx); | |
fbe9c429 | 766 | swscan = test_bit(SCAN_SW_SCANNING, &local->scanning); |
5bb644a0 JB |
767 | mutex_unlock(&local->scan_mtx); |
768 | ||
769 | if (swscan) | |
770 | ieee80211_scan_completed(&local->hw, true); | |
771 | } |