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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 | ||
15 | #include <linux/wireless.h> | |
16 | #include <linux/if_arp.h> | |
078e1e60 | 17 | #include <linux/rtnetlink.h> |
0a51b27e | 18 | #include <net/mac80211.h> |
0a51b27e JB |
19 | |
20 | #include "ieee80211_i.h" | |
24487981 | 21 | #include "driver-ops.h" |
5484e237 | 22 | #include "mesh.h" |
0a51b27e JB |
23 | |
24 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
25 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 26 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 27 | |
c2b13452 | 28 | struct ieee80211_bss * |
5484e237 JB |
29 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
30 | u8 *ssid, u8 ssid_len) | |
31 | { | |
00d3f14c JB |
32 | return (void *)cfg80211_get_bss(local->hw.wiphy, |
33 | ieee80211_get_channel(local->hw.wiphy, | |
34 | freq), | |
35 | bssid, ssid, ssid_len, | |
36 | 0, 0); | |
5484e237 JB |
37 | } |
38 | ||
00d3f14c | 39 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 40 | { |
00d3f14c | 41 | struct ieee80211_bss *bss = (void *)cbss; |
5484e237 | 42 | |
5484e237 JB |
43 | kfree(bss_mesh_id(bss)); |
44 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
45 | } |
46 | ||
47 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 48 | struct ieee80211_bss *bss) |
5484e237 | 49 | { |
00d3f14c | 50 | cfg80211_put_bss((struct cfg80211_bss *)bss); |
5484e237 JB |
51 | } |
52 | ||
c2b13452 | 53 | struct ieee80211_bss * |
5484e237 JB |
54 | ieee80211_bss_info_update(struct ieee80211_local *local, |
55 | struct ieee80211_rx_status *rx_status, | |
56 | struct ieee80211_mgmt *mgmt, | |
57 | size_t len, | |
58 | struct ieee802_11_elems *elems, | |
2a519311 JB |
59 | struct ieee80211_channel *channel, |
60 | bool beacon) | |
5484e237 | 61 | { |
c2b13452 | 62 | struct ieee80211_bss *bss; |
00d3f14c | 63 | int clen; |
2a519311 JB |
64 | s32 signal = 0; |
65 | ||
77965c97 | 66 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 67 | signal = rx_status->signal * 100; |
77965c97 | 68 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 69 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 70 | |
00d3f14c | 71 | bss = (void *)cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
77965c97 | 72 | mgmt, len, signal, GFP_ATOMIC); |
5484e237 | 73 | |
00d3f14c JB |
74 | if (!bss) |
75 | return NULL; | |
76 | ||
77 | bss->cbss.free_priv = ieee80211_rx_bss_free; | |
5484e237 JB |
78 | |
79 | /* save the ERP value so that it is available at association time */ | |
80 | if (elems->erp_info && elems->erp_info_len >= 1) { | |
81 | bss->erp_value = elems->erp_info[0]; | |
82 | bss->has_erp_value = 1; | |
83 | } | |
84 | ||
5484e237 JB |
85 | if (elems->tim) { |
86 | struct ieee80211_tim_ie *tim_ie = | |
87 | (struct ieee80211_tim_ie *)elems->tim; | |
88 | bss->dtim_period = tim_ie->dtim_period; | |
89 | } | |
90 | ||
6a211bf1 JB |
91 | /* set default value for buggy AP/no TIM element */ |
92 | if (bss->dtim_period == 0) | |
5484e237 JB |
93 | bss->dtim_period = 1; |
94 | ||
95 | bss->supp_rates_len = 0; | |
96 | if (elems->supp_rates) { | |
97 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
98 | if (clen > elems->supp_rates_len) | |
99 | clen = elems->supp_rates_len; | |
100 | memcpy(&bss->supp_rates[bss->supp_rates_len], elems->supp_rates, | |
101 | clen); | |
102 | bss->supp_rates_len += clen; | |
103 | } | |
104 | if (elems->ext_supp_rates) { | |
105 | clen = IEEE80211_MAX_SUPP_RATES - bss->supp_rates_len; | |
106 | if (clen > elems->ext_supp_rates_len) | |
107 | clen = elems->ext_supp_rates_len; | |
108 | memcpy(&bss->supp_rates[bss->supp_rates_len], | |
109 | elems->ext_supp_rates, clen); | |
110 | bss->supp_rates_len += clen; | |
111 | } | |
112 | ||
5484e237 JB |
113 | bss->wmm_used = elems->wmm_param || elems->wmm_info; |
114 | ||
115 | if (!beacon) | |
116 | bss->last_probe_resp = jiffies; | |
117 | ||
5484e237 JB |
118 | return bss; |
119 | } | |
0a51b27e | 120 | |
98c8fccf | 121 | ieee80211_rx_result |
f1d58c25 | 122 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 123 | { |
f1d58c25 | 124 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 125 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 126 | struct ieee80211_bss *bss; |
98c8fccf JB |
127 | u8 *elements; |
128 | struct ieee80211_channel *channel; | |
129 | size_t baselen; | |
130 | int freq; | |
131 | __le16 fc; | |
132 | bool presp, beacon = false; | |
133 | struct ieee802_11_elems elems; | |
134 | ||
135 | if (skb->len < 2) | |
136 | return RX_DROP_UNUSABLE; | |
137 | ||
138 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
139 | fc = mgmt->frame_control; | |
140 | ||
141 | if (ieee80211_is_ctl(fc)) | |
142 | return RX_CONTINUE; | |
143 | ||
144 | if (skb->len < 24) | |
145 | return RX_DROP_MONITOR; | |
146 | ||
147 | presp = ieee80211_is_probe_resp(fc); | |
148 | if (presp) { | |
149 | /* ignore ProbeResp to foreign address */ | |
47846c9b | 150 | if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN)) |
98c8fccf JB |
151 | return RX_DROP_MONITOR; |
152 | ||
153 | presp = true; | |
154 | elements = mgmt->u.probe_resp.variable; | |
155 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
156 | } else { | |
157 | beacon = ieee80211_is_beacon(fc); | |
158 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
159 | elements = mgmt->u.beacon.variable; | |
160 | } | |
161 | ||
162 | if (!presp && !beacon) | |
163 | return RX_CONTINUE; | |
164 | ||
165 | if (baselen > skb->len) | |
166 | return RX_DROP_MONITOR; | |
167 | ||
168 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
169 | ||
170 | if (elems.ds_params && elems.ds_params_len == 1) | |
171 | freq = ieee80211_channel_to_frequency(elems.ds_params[0]); | |
172 | else | |
173 | freq = rx_status->freq; | |
174 | ||
175 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
176 | ||
177 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
178 | return RX_DROP_MONITOR; | |
179 | ||
180 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
181 | mgmt, skb->len, &elems, | |
2a519311 | 182 | channel, beacon); |
d048e503 JM |
183 | if (bss) |
184 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf JB |
185 | |
186 | dev_kfree_skb(skb); | |
187 | return RX_QUEUED; | |
188 | } | |
189 | ||
4d36ec58 JB |
190 | /* return false if no more work */ |
191 | static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) | |
192 | { | |
193 | struct cfg80211_scan_request *req = local->scan_req; | |
194 | enum ieee80211_band band; | |
195 | int i, ielen, n_chans; | |
196 | ||
197 | do { | |
198 | if (local->hw_scan_band == IEEE80211_NUM_BANDS) | |
199 | return false; | |
200 | ||
201 | band = local->hw_scan_band; | |
202 | n_chans = 0; | |
203 | for (i = 0; i < req->n_channels; i++) { | |
204 | if (req->channels[i]->band == band) { | |
205 | local->hw_scan_req->channels[n_chans] = | |
206 | req->channels[i]; | |
207 | n_chans++; | |
208 | } | |
209 | } | |
210 | ||
211 | local->hw_scan_band++; | |
212 | } while (!n_chans); | |
213 | ||
214 | local->hw_scan_req->n_channels = n_chans; | |
215 | ||
216 | ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, | |
217 | req->ie, req->ie_len, band); | |
218 | local->hw_scan_req->ie_len = ielen; | |
219 | ||
220 | return true; | |
221 | } | |
222 | ||
9050bdd8 KV |
223 | /* |
224 | * inform AP that we will go to sleep so that it will buffer the frames | |
225 | * while we scan | |
226 | */ | |
227 | static void ieee80211_scan_ps_enable(struct ieee80211_sub_if_data *sdata) | |
228 | { | |
229 | struct ieee80211_local *local = sdata->local; | |
7c3f4bbe VN |
230 | |
231 | local->scan_ps_enabled = false; | |
9050bdd8 KV |
232 | |
233 | /* FIXME: what to do when local->pspolling is true? */ | |
234 | ||
235 | del_timer_sync(&local->dynamic_ps_timer); | |
236 | cancel_work_sync(&local->dynamic_ps_enable_work); | |
237 | ||
238 | if (local->hw.conf.flags & IEEE80211_CONF_PS) { | |
7c3f4bbe | 239 | local->scan_ps_enabled = true; |
9050bdd8 KV |
240 | local->hw.conf.flags &= ~IEEE80211_CONF_PS; |
241 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
242 | } | |
243 | ||
7c3f4bbe VN |
244 | if (!(local->scan_ps_enabled) || |
245 | !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)) | |
9050bdd8 KV |
246 | /* |
247 | * If power save was enabled, no need to send a nullfunc | |
248 | * frame because AP knows that we are sleeping. But if the | |
249 | * hardware is creating the nullfunc frame for power save | |
250 | * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not | |
251 | * enabled) and power save was enabled, the firmware just | |
252 | * sent a null frame with power save disabled. So we need | |
253 | * to send a new nullfunc frame to inform the AP that we | |
254 | * are again sleeping. | |
255 | */ | |
256 | ieee80211_send_nullfunc(local, sdata, 1); | |
257 | } | |
258 | ||
259 | /* inform AP that we are awake again, unless power save is enabled */ | |
260 | static void ieee80211_scan_ps_disable(struct ieee80211_sub_if_data *sdata) | |
261 | { | |
262 | struct ieee80211_local *local = sdata->local; | |
263 | ||
965bedad | 264 | if (!local->ps_sdata) |
9050bdd8 | 265 | ieee80211_send_nullfunc(local, sdata, 0); |
7c3f4bbe | 266 | else if (local->scan_ps_enabled) { |
9050bdd8 KV |
267 | /* |
268 | * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware | |
269 | * will send a nullfunc frame with the powersave bit set | |
270 | * even though the AP already knows that we are sleeping. | |
271 | * This could be avoided by sending a null frame with power | |
272 | * save bit disabled before enabling the power save, but | |
273 | * this doesn't gain anything. | |
274 | * | |
275 | * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need | |
276 | * to send a nullfunc frame because AP already knows that | |
277 | * we are sleeping, let's just enable power save mode in | |
278 | * hardware. | |
279 | */ | |
280 | local->hw.conf.flags |= IEEE80211_CONF_PS; | |
281 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); | |
7c3f4bbe VN |
282 | } else if (local->hw.conf.dynamic_ps_timeout > 0) { |
283 | /* | |
284 | * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer | |
285 | * had been running before leaving the operating channel, | |
286 | * restart the timer now and send a nullfunc frame to inform | |
287 | * the AP that we are awake. | |
288 | */ | |
289 | ieee80211_send_nullfunc(local, sdata, 0); | |
290 | mod_timer(&local->dynamic_ps_timer, jiffies + | |
291 | msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); | |
9050bdd8 KV |
292 | } |
293 | } | |
294 | ||
2a519311 | 295 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) |
0a51b27e JB |
296 | { |
297 | struct ieee80211_local *local = hw_to_local(hw); | |
298 | struct ieee80211_sub_if_data *sdata; | |
f3b85252 | 299 | bool was_hw_scan; |
0a51b27e | 300 | |
f3b85252 | 301 | mutex_lock(&local->scan_mtx); |
5bc75728 | 302 | |
6d3560d4 JB |
303 | /* |
304 | * It's ok to abort a not-yet-running scan (that | |
305 | * we have one at all will be verified by checking | |
306 | * local->scan_req next), but not to complete it | |
307 | * successfully. | |
308 | */ | |
309 | if (WARN_ON(!local->scanning && !aborted)) | |
310 | aborted = true; | |
5bc75728 | 311 | |
f3b85252 JB |
312 | if (WARN_ON(!local->scan_req)) { |
313 | mutex_unlock(&local->scan_mtx); | |
314 | return; | |
de95a54b JB |
315 | } |
316 | ||
4d36ec58 JB |
317 | was_hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
318 | if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { | |
319 | ieee80211_queue_delayed_work(&local->hw, | |
320 | &local->scan_work, 0); | |
321 | mutex_unlock(&local->scan_mtx); | |
322 | return; | |
323 | } | |
324 | ||
325 | kfree(local->hw_scan_req); | |
326 | local->hw_scan_req = NULL; | |
f3b85252 | 327 | |
5ba63533 | 328 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
329 | cfg80211_scan_done(local->scan_req, aborted); |
330 | local->scan_req = NULL; | |
15db0b7f | 331 | local->scan_sdata = NULL; |
2a519311 | 332 | |
fbe9c429 | 333 | local->scanning = 0; |
58905ca5 | 334 | local->scan_channel = NULL; |
f3b85252 JB |
335 | |
336 | /* we only have to protect scan_req and hw/sw scan */ | |
337 | mutex_unlock(&local->scan_mtx); | |
338 | ||
e8975581 | 339 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); |
5cff20e6 JB |
340 | if (was_hw_scan) |
341 | goto done; | |
0a51b27e | 342 | |
3ac64bee | 343 | ieee80211_configure_filter(local); |
0a51b27e | 344 | |
24487981 | 345 | drv_sw_scan_complete(local); |
80e775bf | 346 | |
078e1e60 JB |
347 | mutex_lock(&local->iflist_mtx); |
348 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 349 | if (!ieee80211_sdata_running(sdata)) |
fb9ddbf0 JB |
350 | continue; |
351 | ||
0a51b27e | 352 | /* Tell AP we're back */ |
05c914fe | 353 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { |
77fdaa12 | 354 | if (sdata->u.mgd.associated) { |
9050bdd8 | 355 | ieee80211_scan_ps_disable(sdata); |
53623f1a | 356 | netif_wake_queue(sdata->dev); |
0a51b27e JB |
357 | } |
358 | } else | |
53623f1a | 359 | netif_wake_queue(sdata->dev); |
078e1e60 | 360 | |
14b80724 JB |
361 | /* re-enable 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); | |
0a51b27e | 367 | } |
078e1e60 | 368 | mutex_unlock(&local->iflist_mtx); |
0a51b27e JB |
369 | |
370 | done: | |
5cff20e6 | 371 | ieee80211_recalc_idle(local); |
0a51b27e | 372 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 373 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 374 | ieee80211_mesh_notify_scan_completed(local); |
0a51b27e JB |
375 | } |
376 | EXPORT_SYMBOL(ieee80211_scan_completed); | |
377 | ||
f3b85252 JB |
378 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
379 | { | |
380 | struct ieee80211_sub_if_data *sdata; | |
381 | ||
382 | /* | |
383 | * Hardware/driver doesn't support hw_scan, so use software | |
384 | * scanning instead. First send a nullfunc frame with power save | |
385 | * bit on so that AP will buffer the frames for us while we are not | |
386 | * listening, then send probe requests to each channel and wait for | |
387 | * the responses. After all channels are scanned, tune back to the | |
388 | * original channel and send a nullfunc frame with power save bit | |
389 | * off to trigger the AP to send us all the buffered frames. | |
390 | * | |
391 | * Note that while local->sw_scanning is true everything else but | |
392 | * nullfunc frames and probe requests will be dropped in | |
393 | * ieee80211_tx_h_check_assoc(). | |
394 | */ | |
24487981 | 395 | drv_sw_scan_start(local); |
f3b85252 JB |
396 | |
397 | mutex_lock(&local->iflist_mtx); | |
398 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 399 | if (!ieee80211_sdata_running(sdata)) |
f3b85252 JB |
400 | continue; |
401 | ||
402 | /* disable beaconing */ | |
403 | if (sdata->vif.type == NL80211_IFTYPE_AP || | |
404 | sdata->vif.type == NL80211_IFTYPE_ADHOC || | |
405 | sdata->vif.type == NL80211_IFTYPE_MESH_POINT) | |
2d0ddec5 JB |
406 | ieee80211_bss_info_change_notify( |
407 | sdata, BSS_CHANGED_BEACON_ENABLED); | |
f3b85252 | 408 | |
142b9f50 HS |
409 | /* |
410 | * only handle non-STA interfaces here, STA interfaces | |
411 | * are handled in the scan state machine | |
412 | */ | |
413 | if (sdata->vif.type != NL80211_IFTYPE_STATION) | |
53623f1a | 414 | netif_stop_queue(sdata->dev); |
f3b85252 JB |
415 | } |
416 | mutex_unlock(&local->iflist_mtx); | |
417 | ||
977923b0 | 418 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
419 | local->scan_channel_idx = 0; |
420 | ||
a80f7c0b JB |
421 | drv_flush(local, false); |
422 | ||
3ac64bee | 423 | ieee80211_configure_filter(local); |
f3b85252 | 424 | |
42935eca LR |
425 | ieee80211_queue_delayed_work(&local->hw, |
426 | &local->scan_work, | |
427 | IEEE80211_CHANNEL_TIME); | |
f3b85252 JB |
428 | |
429 | return 0; | |
430 | } | |
431 | ||
432 | ||
433 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
434 | struct cfg80211_scan_request *req) | |
435 | { | |
436 | struct ieee80211_local *local = sdata->local; | |
437 | struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; | |
438 | int rc; | |
439 | ||
440 | if (local->scan_req) | |
441 | return -EBUSY; | |
442 | ||
443 | if (local->ops->hw_scan) { | |
444 | u8 *ies; | |
f3b85252 | 445 | |
4d36ec58 JB |
446 | local->hw_scan_req = kmalloc( |
447 | sizeof(*local->hw_scan_req) + | |
448 | req->n_channels * sizeof(req->channels[0]) + | |
449 | 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + | |
450 | req->ie_len, GFP_KERNEL); | |
451 | if (!local->hw_scan_req) | |
f3b85252 JB |
452 | return -ENOMEM; |
453 | ||
4d36ec58 JB |
454 | local->hw_scan_req->ssids = req->ssids; |
455 | local->hw_scan_req->n_ssids = req->n_ssids; | |
456 | ies = (u8 *)local->hw_scan_req + | |
457 | sizeof(*local->hw_scan_req) + | |
458 | req->n_channels * sizeof(req->channels[0]); | |
459 | local->hw_scan_req->ie = ies; | |
460 | ||
461 | local->hw_scan_band = 0; | |
f3b85252 JB |
462 | } |
463 | ||
464 | local->scan_req = req; | |
465 | local->scan_sdata = sdata; | |
466 | ||
5ba63533 | 467 | if (req != local->int_scan_req && |
f3b85252 | 468 | sdata->vif.type == NL80211_IFTYPE_STATION && |
77fdaa12 JB |
469 | !list_empty(&ifmgd->work_list)) { |
470 | /* actually wait for the work it's doing to finish/time out */ | |
f3b85252 JB |
471 | set_bit(IEEE80211_STA_REQ_SCAN, &ifmgd->request); |
472 | return 0; | |
473 | } | |
474 | ||
475 | if (local->ops->hw_scan) | |
fbe9c429 | 476 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 477 | else |
fbe9c429 | 478 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
f3b85252 JB |
479 | /* |
480 | * Kicking off the scan need not be protected, | |
481 | * only the scan variable stuff, since now | |
482 | * local->scan_req is assigned and other callers | |
483 | * will abort their scan attempts. | |
484 | * | |
485 | * This avoids getting a scan_mtx -> iflist_mtx | |
486 | * dependency, so that the scan completed calls | |
487 | * have more locking freedom. | |
488 | */ | |
5cff20e6 JB |
489 | |
490 | ieee80211_recalc_idle(local); | |
f3b85252 JB |
491 | mutex_unlock(&local->scan_mtx); |
492 | ||
4d36ec58 JB |
493 | if (local->ops->hw_scan) { |
494 | WARN_ON(!ieee80211_prep_hw_scan(local)); | |
495 | rc = drv_hw_scan(local, local->hw_scan_req); | |
496 | } else | |
f3b85252 JB |
497 | rc = ieee80211_start_sw_scan(local); |
498 | ||
499 | mutex_lock(&local->scan_mtx); | |
500 | ||
501 | if (rc) { | |
4d36ec58 JB |
502 | kfree(local->hw_scan_req); |
503 | local->hw_scan_req = NULL; | |
fbe9c429 | 504 | local->scanning = 0; |
f3b85252 | 505 | |
5cff20e6 JB |
506 | ieee80211_recalc_idle(local); |
507 | ||
f3b85252 JB |
508 | local->scan_req = NULL; |
509 | local->scan_sdata = NULL; | |
510 | } | |
511 | ||
512 | return rc; | |
513 | } | |
514 | ||
2fb3f028 HS |
515 | static int ieee80211_scan_state_decision(struct ieee80211_local *local, |
516 | unsigned long *next_delay) | |
7d3be3cc | 517 | { |
142b9f50 HS |
518 | bool associated = false; |
519 | struct ieee80211_sub_if_data *sdata; | |
520 | ||
521 | /* if no more bands/channels left, complete scan and advance to the idle state */ | |
7d3be3cc HS |
522 | if (local->scan_channel_idx >= local->scan_req->n_channels) { |
523 | ieee80211_scan_completed(&local->hw, false); | |
524 | return 1; | |
525 | } | |
2fb3f028 | 526 | |
142b9f50 HS |
527 | /* check if at least one STA interface is associated */ |
528 | mutex_lock(&local->iflist_mtx); | |
529 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 530 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
531 | continue; |
532 | ||
533 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
534 | if (sdata->u.mgd.associated) { | |
535 | associated = true; | |
536 | break; | |
537 | } | |
538 | } | |
539 | } | |
540 | mutex_unlock(&local->iflist_mtx); | |
541 | ||
542 | if (local->scan_channel) { | |
543 | /* | |
544 | * we're currently scanning a different channel, let's | |
545 | * switch back to the operating channel now if at least | |
546 | * one interface is associated. Otherwise just scan the | |
547 | * next channel | |
548 | */ | |
549 | if (associated) | |
977923b0 | 550 | local->next_scan_state = SCAN_ENTER_OPER_CHANNEL; |
142b9f50 | 551 | else |
977923b0 | 552 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
553 | } else { |
554 | /* | |
555 | * we're on the operating channel currently, let's | |
556 | * leave that channel now to scan another one | |
557 | */ | |
977923b0 | 558 | local->next_scan_state = SCAN_LEAVE_OPER_CHANNEL; |
142b9f50 HS |
559 | } |
560 | ||
2fb3f028 | 561 | *next_delay = 0; |
2fb3f028 HS |
562 | return 0; |
563 | } | |
564 | ||
142b9f50 HS |
565 | static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *local, |
566 | unsigned long *next_delay) | |
567 | { | |
568 | struct ieee80211_sub_if_data *sdata; | |
569 | ||
570 | /* | |
571 | * notify the AP about us leaving the channel and stop all STA interfaces | |
572 | */ | |
573 | mutex_lock(&local->iflist_mtx); | |
574 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 575 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
576 | continue; |
577 | ||
578 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
53623f1a | 579 | netif_stop_queue(sdata->dev); |
142b9f50 HS |
580 | if (sdata->u.mgd.associated) |
581 | ieee80211_scan_ps_enable(sdata); | |
582 | } | |
583 | } | |
584 | mutex_unlock(&local->iflist_mtx); | |
585 | ||
586 | __set_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
587 | ||
a80f7c0b JB |
588 | /* |
589 | * What if the nullfunc frames didn't arrive? | |
590 | */ | |
591 | drv_flush(local, false); | |
592 | if (local->ops->flush) | |
593 | *next_delay = 0; | |
594 | else | |
595 | *next_delay = HZ / 10; | |
596 | ||
142b9f50 | 597 | /* advance to the next channel to be scanned */ |
977923b0 | 598 | local->next_scan_state = SCAN_SET_CHANNEL; |
142b9f50 HS |
599 | } |
600 | ||
601 | static void ieee80211_scan_state_enter_oper_channel(struct ieee80211_local *local, | |
602 | unsigned long *next_delay) | |
603 | { | |
604 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
605 | ||
606 | /* switch back to the operating channel */ | |
607 | local->scan_channel = NULL; | |
608 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
609 | ||
610 | /* | |
611 | * notify the AP about us being back and restart all STA interfaces | |
612 | */ | |
613 | mutex_lock(&local->iflist_mtx); | |
614 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 615 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
616 | continue; |
617 | ||
618 | /* Tell AP we're back */ | |
619 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
620 | if (sdata->u.mgd.associated) | |
621 | ieee80211_scan_ps_disable(sdata); | |
53623f1a | 622 | netif_wake_queue(sdata->dev); |
142b9f50 HS |
623 | } |
624 | } | |
625 | mutex_unlock(&local->iflist_mtx); | |
626 | ||
627 | __clear_bit(SCAN_OFF_CHANNEL, &local->scanning); | |
628 | ||
629 | *next_delay = HZ / 5; | |
977923b0 | 630 | local->next_scan_state = SCAN_DECISION; |
142b9f50 HS |
631 | } |
632 | ||
2fb3f028 HS |
633 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
634 | unsigned long *next_delay) | |
635 | { | |
636 | int skip; | |
637 | struct ieee80211_channel *chan; | |
2fb3f028 | 638 | |
7d3be3cc HS |
639 | skip = 0; |
640 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
641 | ||
584991dc JB |
642 | local->scan_channel = chan; |
643 | if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) | |
7d3be3cc HS |
644 | skip = 1; |
645 | ||
7d3be3cc HS |
646 | /* advance state machine to next channel/band */ |
647 | local->scan_channel_idx++; | |
648 | ||
0ee9c13c HS |
649 | if (skip) { |
650 | /* if we skip this channel return to the decision state */ | |
651 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 652 | return; |
0ee9c13c | 653 | } |
7d3be3cc HS |
654 | |
655 | /* | |
656 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
657 | * (which unfortunately doesn't say _why_ step a) is done, | |
658 | * but it waits for the probe delay or until a frame is | |
659 | * received - and the received frame would update the NAV). | |
660 | * For now, we do not support waiting until a frame is | |
661 | * received. | |
662 | * | |
663 | * In any case, it is not necessary for a passive scan. | |
664 | */ | |
665 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
666 | !local->scan_req->n_ssids) { | |
667 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 668 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 669 | return; |
7d3be3cc HS |
670 | } |
671 | ||
2fb3f028 | 672 | /* active scan, send probes */ |
7d3be3cc | 673 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 674 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
675 | } |
676 | ||
677 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
678 | unsigned long *next_delay) | |
679 | { | |
680 | int i; | |
681 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
682 | ||
683 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
684 | ieee80211_send_probe_req( | |
685 | sdata, NULL, | |
686 | local->scan_req->ssids[i].ssid, | |
687 | local->scan_req->ssids[i].ssid_len, | |
688 | local->scan_req->ie, local->scan_req->ie_len); | |
689 | ||
690 | /* | |
691 | * After sending probe requests, wait for probe responses | |
692 | * on the channel. | |
693 | */ | |
694 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 695 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
696 | } |
697 | ||
c2b13452 | 698 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
699 | { |
700 | struct ieee80211_local *local = | |
701 | container_of(work, struct ieee80211_local, scan_work.work); | |
702 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
0a51b27e JB |
703 | unsigned long next_delay = 0; |
704 | ||
f3b85252 JB |
705 | mutex_lock(&local->scan_mtx); |
706 | if (!sdata || !local->scan_req) { | |
707 | mutex_unlock(&local->scan_mtx); | |
708 | return; | |
709 | } | |
710 | ||
4d36ec58 JB |
711 | if (local->hw_scan_req) { |
712 | int rc = drv_hw_scan(local, local->hw_scan_req); | |
713 | mutex_unlock(&local->scan_mtx); | |
714 | if (rc) | |
715 | ieee80211_scan_completed(&local->hw, true); | |
716 | return; | |
717 | } | |
718 | ||
fbe9c429 | 719 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
720 | struct cfg80211_scan_request *req = local->scan_req; |
721 | int rc; | |
722 | ||
723 | local->scan_req = NULL; | |
15db0b7f | 724 | local->scan_sdata = NULL; |
f3b85252 JB |
725 | |
726 | rc = __ieee80211_start_scan(sdata, req); | |
727 | mutex_unlock(&local->scan_mtx); | |
728 | ||
729 | if (rc) | |
730 | ieee80211_scan_completed(&local->hw, true); | |
731 | return; | |
732 | } | |
733 | ||
734 | mutex_unlock(&local->scan_mtx); | |
735 | ||
5bc75728 JB |
736 | /* |
737 | * Avoid re-scheduling when the sdata is going away. | |
738 | */ | |
9607e6b6 | 739 | if (!ieee80211_sdata_running(sdata)) { |
f3b85252 | 740 | ieee80211_scan_completed(&local->hw, true); |
0a51b27e | 741 | return; |
f3b85252 | 742 | } |
0a51b27e | 743 | |
f502d09b HS |
744 | /* |
745 | * as long as no delay is required advance immediately | |
746 | * without scheduling a new work | |
747 | */ | |
748 | do { | |
977923b0 | 749 | switch (local->next_scan_state) { |
2fb3f028 HS |
750 | case SCAN_DECISION: |
751 | if (ieee80211_scan_state_decision(local, &next_delay)) | |
f502d09b HS |
752 | return; |
753 | break; | |
2fb3f028 HS |
754 | case SCAN_SET_CHANNEL: |
755 | ieee80211_scan_state_set_channel(local, &next_delay); | |
756 | break; | |
f502d09b HS |
757 | case SCAN_SEND_PROBE: |
758 | ieee80211_scan_state_send_probe(local, &next_delay); | |
759 | break; | |
142b9f50 HS |
760 | case SCAN_LEAVE_OPER_CHANNEL: |
761 | ieee80211_scan_state_leave_oper_channel(local, &next_delay); | |
762 | break; | |
763 | case SCAN_ENTER_OPER_CHANNEL: | |
764 | ieee80211_scan_state_enter_oper_channel(local, &next_delay); | |
765 | break; | |
f502d09b HS |
766 | } |
767 | } while (next_delay == 0); | |
0a51b27e | 768 | |
42935eca | 769 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
0a51b27e JB |
770 | } |
771 | ||
f3b85252 JB |
772 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
773 | struct cfg80211_scan_request *req) | |
0a51b27e | 774 | { |
f3b85252 | 775 | int res; |
de95a54b | 776 | |
f3b85252 JB |
777 | mutex_lock(&sdata->local->scan_mtx); |
778 | res = __ieee80211_start_scan(sdata, req); | |
779 | mutex_unlock(&sdata->local->scan_mtx); | |
0a51b27e | 780 | |
f3b85252 | 781 | return res; |
0a51b27e JB |
782 | } |
783 | ||
f3b85252 JB |
784 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
785 | const u8 *ssid, u8 ssid_len) | |
0a51b27e | 786 | { |
0a51b27e | 787 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 788 | int ret = -EBUSY; |
2a519311 | 789 | |
f3b85252 | 790 | mutex_lock(&local->scan_mtx); |
0a51b27e | 791 | |
f3b85252 JB |
792 | /* busy scanning */ |
793 | if (local->scan_req) | |
794 | goto unlock; | |
9116dd01 | 795 | |
5ba63533 JB |
796 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
797 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 798 | |
5ba63533 | 799 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 JB |
800 | unlock: |
801 | mutex_unlock(&local->scan_mtx); | |
802 | return ret; | |
0a51b27e | 803 | } |
5bb644a0 JB |
804 | |
805 | void ieee80211_scan_cancel(struct ieee80211_local *local) | |
806 | { | |
15db0b7f | 807 | bool abortscan; |
5bb644a0 JB |
808 | |
809 | cancel_delayed_work_sync(&local->scan_work); | |
810 | ||
811 | /* | |
812 | * Only call this function when a scan can't be | |
813 | * queued -- mostly at suspend under RTNL. | |
814 | */ | |
815 | mutex_lock(&local->scan_mtx); | |
15db0b7f JB |
816 | abortscan = test_bit(SCAN_SW_SCANNING, &local->scanning) || |
817 | (!local->scanning && local->scan_req); | |
5bb644a0 JB |
818 | mutex_unlock(&local->scan_mtx); |
819 | ||
15db0b7f | 820 | if (abortscan) |
5bb644a0 JB |
821 | ieee80211_scan_completed(&local->hw, true); |
822 | } |