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 | ||
0a51b27e | 15 | #include <linux/if_arp.h> |
888d04df | 16 | #include <linux/etherdevice.h> |
078e1e60 | 17 | #include <linux/rtnetlink.h> |
e8db0be1 | 18 | #include <linux/pm_qos.h> |
df13cce5 | 19 | #include <net/sch_generic.h> |
5a0e3ad6 | 20 | #include <linux/slab.h> |
bc3b2d7f | 21 | #include <linux/export.h> |
0a51b27e | 22 | #include <net/mac80211.h> |
0a51b27e JB |
23 | |
24 | #include "ieee80211_i.h" | |
24487981 | 25 | #include "driver-ops.h" |
5484e237 | 26 | #include "mesh.h" |
0a51b27e JB |
27 | |
28 | #define IEEE80211_PROBE_DELAY (HZ / 33) | |
29 | #define IEEE80211_CHANNEL_TIME (HZ / 33) | |
96f7e739 | 30 | #define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 8) |
0a51b27e | 31 | |
00d3f14c | 32 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 33 | { |
0c1ad2ca | 34 | struct ieee80211_bss *bss = (void *)cbss->priv; |
5484e237 | 35 | |
5484e237 JB |
36 | kfree(bss_mesh_id(bss)); |
37 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
38 | } |
39 | ||
40 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 41 | struct ieee80211_bss *bss) |
5484e237 | 42 | { |
0c1ad2ca JB |
43 | if (!bss) |
44 | return; | |
45 | cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); | |
5484e237 JB |
46 | } |
47 | ||
ab13315a KV |
48 | static bool is_uapsd_supported(struct ieee802_11_elems *elems) |
49 | { | |
50 | u8 qos_info; | |
51 | ||
52 | if (elems->wmm_info && elems->wmm_info_len == 7 | |
53 | && elems->wmm_info[5] == 1) | |
54 | qos_info = elems->wmm_info[6]; | |
55 | else if (elems->wmm_param && elems->wmm_param_len == 24 | |
56 | && elems->wmm_param[5] == 1) | |
57 | qos_info = elems->wmm_param[6]; | |
58 | else | |
59 | /* no valid wmm information or parameter element found */ | |
60 | return false; | |
61 | ||
62 | return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; | |
63 | } | |
64 | ||
c2b13452 | 65 | struct ieee80211_bss * |
5484e237 JB |
66 | ieee80211_bss_info_update(struct ieee80211_local *local, |
67 | struct ieee80211_rx_status *rx_status, | |
68 | struct ieee80211_mgmt *mgmt, | |
69 | size_t len, | |
70 | struct ieee802_11_elems *elems, | |
2a519311 JB |
71 | struct ieee80211_channel *channel, |
72 | bool beacon) | |
5484e237 | 73 | { |
0c1ad2ca | 74 | struct cfg80211_bss *cbss; |
c2b13452 | 75 | struct ieee80211_bss *bss; |
f0b058b6 | 76 | int clen, srlen; |
2a519311 JB |
77 | s32 signal = 0; |
78 | ||
77965c97 | 79 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 80 | signal = rx_status->signal * 100; |
77965c97 | 81 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 82 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 83 | |
0c1ad2ca JB |
84 | cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
85 | mgmt, len, signal, GFP_ATOMIC); | |
5484e237 | 86 | |
0c1ad2ca | 87 | if (!cbss) |
00d3f14c JB |
88 | return NULL; |
89 | ||
0c1ad2ca JB |
90 | cbss->free_priv = ieee80211_rx_bss_free; |
91 | bss = (void *)cbss->priv; | |
5484e237 | 92 | |
fcff4f10 PS |
93 | if (elems->parse_error) { |
94 | if (beacon) | |
95 | bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; | |
96 | else | |
97 | bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; | |
98 | } else { | |
99 | if (beacon) | |
100 | bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; | |
101 | else | |
102 | bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; | |
103 | } | |
104 | ||
5484e237 | 105 | /* save the ERP value so that it is available at association time */ |
fcff4f10 PS |
106 | if (elems->erp_info && elems->erp_info_len >= 1 && |
107 | (!elems->parse_error || | |
108 | !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { | |
5484e237 | 109 | bss->erp_value = elems->erp_info[0]; |
3db1cd5c | 110 | bss->has_erp_value = true; |
fcff4f10 PS |
111 | if (!elems->parse_error) |
112 | bss->valid_data |= IEEE80211_BSS_VALID_ERP; | |
5484e237 JB |
113 | } |
114 | ||
fcff4f10 PS |
115 | if (elems->tim && (!elems->parse_error || |
116 | !(bss->valid_data & IEEE80211_BSS_VALID_DTIM))) { | |
5484e237 JB |
117 | struct ieee80211_tim_ie *tim_ie = |
118 | (struct ieee80211_tim_ie *)elems->tim; | |
119 | bss->dtim_period = tim_ie->dtim_period; | |
fcff4f10 PS |
120 | if (!elems->parse_error) |
121 | bss->valid_data |= IEEE80211_BSS_VALID_DTIM; | |
5484e237 JB |
122 | } |
123 | ||
e5b900d2 JB |
124 | /* If the beacon had no TIM IE, or it was invalid, use 1 */ |
125 | if (beacon && !bss->dtim_period) | |
126 | bss->dtim_period = 1; | |
127 | ||
f0b058b6 | 128 | /* replace old supported rates if we get new values */ |
fcff4f10 PS |
129 | if (!elems->parse_error || |
130 | !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { | |
131 | srlen = 0; | |
132 | if (elems->supp_rates) { | |
133 | clen = IEEE80211_MAX_SUPP_RATES; | |
134 | if (clen > elems->supp_rates_len) | |
135 | clen = elems->supp_rates_len; | |
136 | memcpy(bss->supp_rates, elems->supp_rates, clen); | |
137 | srlen += clen; | |
138 | } | |
139 | if (elems->ext_supp_rates) { | |
140 | clen = IEEE80211_MAX_SUPP_RATES - srlen; | |
141 | if (clen > elems->ext_supp_rates_len) | |
142 | clen = elems->ext_supp_rates_len; | |
143 | memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, | |
144 | clen); | |
145 | srlen += clen; | |
146 | } | |
147 | if (srlen) { | |
148 | bss->supp_rates_len = srlen; | |
149 | if (!elems->parse_error) | |
150 | bss->valid_data |= IEEE80211_BSS_VALID_RATES; | |
151 | } | |
5484e237 | 152 | } |
5484e237 | 153 | |
fcff4f10 PS |
154 | if (!elems->parse_error || |
155 | !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { | |
156 | bss->wmm_used = elems->wmm_param || elems->wmm_info; | |
157 | bss->uapsd_supported = is_uapsd_supported(elems); | |
158 | if (!elems->parse_error) | |
159 | bss->valid_data |= IEEE80211_BSS_VALID_WMM; | |
160 | } | |
5484e237 JB |
161 | |
162 | if (!beacon) | |
163 | bss->last_probe_resp = jiffies; | |
164 | ||
5484e237 JB |
165 | return bss; |
166 | } | |
0a51b27e | 167 | |
98c8fccf | 168 | ieee80211_rx_result |
f1d58c25 | 169 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 170 | { |
f1d58c25 | 171 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 172 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 173 | struct ieee80211_bss *bss; |
98c8fccf JB |
174 | u8 *elements; |
175 | struct ieee80211_channel *channel; | |
176 | size_t baselen; | |
177 | int freq; | |
178 | __le16 fc; | |
179 | bool presp, beacon = false; | |
180 | struct ieee802_11_elems elems; | |
181 | ||
182 | if (skb->len < 2) | |
183 | return RX_DROP_UNUSABLE; | |
184 | ||
185 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
186 | fc = mgmt->frame_control; | |
187 | ||
188 | if (ieee80211_is_ctl(fc)) | |
189 | return RX_CONTINUE; | |
190 | ||
191 | if (skb->len < 24) | |
306fe938 | 192 | return RX_CONTINUE; |
98c8fccf JB |
193 | |
194 | presp = ieee80211_is_probe_resp(fc); | |
195 | if (presp) { | |
196 | /* ignore ProbeResp to foreign address */ | |
888d04df | 197 | if (compare_ether_addr(mgmt->da, sdata->vif.addr)) |
98c8fccf JB |
198 | return RX_DROP_MONITOR; |
199 | ||
200 | presp = true; | |
201 | elements = mgmt->u.probe_resp.variable; | |
202 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
203 | } else { | |
204 | beacon = ieee80211_is_beacon(fc); | |
205 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
206 | elements = mgmt->u.beacon.variable; | |
207 | } | |
208 | ||
209 | if (!presp && !beacon) | |
210 | return RX_CONTINUE; | |
211 | ||
212 | if (baselen > skb->len) | |
213 | return RX_DROP_MONITOR; | |
214 | ||
215 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
216 | ||
217 | if (elems.ds_params && elems.ds_params_len == 1) | |
59eb21a6 BR |
218 | freq = ieee80211_channel_to_frequency(elems.ds_params[0], |
219 | rx_status->band); | |
98c8fccf JB |
220 | else |
221 | freq = rx_status->freq; | |
222 | ||
223 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
224 | ||
225 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
226 | return RX_DROP_MONITOR; | |
227 | ||
228 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
229 | mgmt, skb->len, &elems, | |
2a519311 | 230 | channel, beacon); |
d048e503 JM |
231 | if (bss) |
232 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf | 233 | |
07ef03ee | 234 | if (channel == sdata->local->oper_channel) |
b23b025f BG |
235 | return RX_CONTINUE; |
236 | ||
98c8fccf JB |
237 | dev_kfree_skb(skb); |
238 | return RX_QUEUED; | |
239 | } | |
240 | ||
4d36ec58 JB |
241 | /* return false if no more work */ |
242 | static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) | |
243 | { | |
244 | struct cfg80211_scan_request *req = local->scan_req; | |
245 | enum ieee80211_band band; | |
246 | int i, ielen, n_chans; | |
247 | ||
248 | do { | |
249 | if (local->hw_scan_band == IEEE80211_NUM_BANDS) | |
250 | return false; | |
251 | ||
252 | band = local->hw_scan_band; | |
253 | n_chans = 0; | |
254 | for (i = 0; i < req->n_channels; i++) { | |
255 | if (req->channels[i]->band == band) { | |
256 | local->hw_scan_req->channels[n_chans] = | |
257 | req->channels[i]; | |
258 | n_chans++; | |
259 | } | |
260 | } | |
261 | ||
262 | local->hw_scan_band++; | |
263 | } while (!n_chans); | |
264 | ||
265 | local->hw_scan_req->n_channels = n_chans; | |
266 | ||
267 | ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, | |
8ee31080 | 268 | req->ie, req->ie_len, band, |
85a237fe | 269 | req->rates[band], 0); |
4d36ec58 | 270 | local->hw_scan_req->ie_len = ielen; |
dcd83976 | 271 | local->hw_scan_req->no_cck = req->no_cck; |
4d36ec58 JB |
272 | |
273 | return true; | |
274 | } | |
275 | ||
d07bfd8b | 276 | static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted, |
e229f844 | 277 | bool was_hw_scan) |
0a51b27e JB |
278 | { |
279 | struct ieee80211_local *local = hw_to_local(hw); | |
0a51b27e | 280 | |
e229f844 | 281 | lockdep_assert_held(&local->mtx); |
5bc75728 | 282 | |
6d3560d4 JB |
283 | /* |
284 | * It's ok to abort a not-yet-running scan (that | |
285 | * we have one at all will be verified by checking | |
286 | * local->scan_req next), but not to complete it | |
287 | * successfully. | |
288 | */ | |
289 | if (WARN_ON(!local->scanning && !aborted)) | |
290 | aborted = true; | |
5bc75728 | 291 | |
e229f844 | 292 | if (WARN_ON(!local->scan_req)) |
d07bfd8b | 293 | return; |
de95a54b | 294 | |
4d36ec58 | 295 | if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { |
6eb11a9a SG |
296 | int rc = drv_hw_scan(local, local->scan_sdata, local->hw_scan_req); |
297 | if (rc == 0) | |
d07bfd8b | 298 | return; |
4d36ec58 JB |
299 | } |
300 | ||
301 | kfree(local->hw_scan_req); | |
302 | local->hw_scan_req = NULL; | |
f3b85252 | 303 | |
5ba63533 | 304 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
305 | cfg80211_scan_done(local->scan_req, aborted); |
306 | local->scan_req = NULL; | |
15db0b7f | 307 | local->scan_sdata = NULL; |
2a519311 | 308 | |
fbe9c429 | 309 | local->scanning = 0; |
58905ca5 | 310 | local->scan_channel = NULL; |
f3b85252 | 311 | |
07ef03ee JB |
312 | /* Set power back to normal operating levels. */ |
313 | ieee80211_hw_config(local, 0); | |
a0daa0e7 | 314 | |
e229f844 SG |
315 | if (!was_hw_scan) { |
316 | ieee80211_configure_filter(local); | |
317 | drv_sw_scan_complete(local); | |
e76aadc5 | 318 | ieee80211_offchannel_return(local, true); |
e229f844 | 319 | } |
0a51b27e | 320 | |
5cff20e6 | 321 | ieee80211_recalc_idle(local); |
e229f844 | 322 | |
0a51b27e | 323 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 324 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 325 | ieee80211_mesh_notify_scan_completed(local); |
81ac3462 | 326 | ieee80211_queue_work(&local->hw, &local->work_work); |
0a51b27e | 327 | } |
8789d459 JB |
328 | |
329 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) | |
330 | { | |
331 | struct ieee80211_local *local = hw_to_local(hw); | |
332 | ||
333 | trace_api_scan_completed(local, aborted); | |
334 | ||
335 | set_bit(SCAN_COMPLETED, &local->scanning); | |
336 | if (aborted) | |
337 | set_bit(SCAN_ABORTED, &local->scanning); | |
338 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); | |
339 | } | |
0a51b27e JB |
340 | EXPORT_SYMBOL(ieee80211_scan_completed); |
341 | ||
f3b85252 JB |
342 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
343 | { | |
f3b85252 JB |
344 | /* |
345 | * Hardware/driver doesn't support hw_scan, so use software | |
346 | * scanning instead. First send a nullfunc frame with power save | |
347 | * bit on so that AP will buffer the frames for us while we are not | |
348 | * listening, then send probe requests to each channel and wait for | |
349 | * the responses. After all channels are scanned, tune back to the | |
350 | * original channel and send a nullfunc frame with power save bit | |
351 | * off to trigger the AP to send us all the buffered frames. | |
352 | * | |
353 | * Note that while local->sw_scanning is true everything else but | |
354 | * nullfunc frames and probe requests will be dropped in | |
355 | * ieee80211_tx_h_check_assoc(). | |
356 | */ | |
24487981 | 357 | drv_sw_scan_start(local); |
f3b85252 | 358 | |
de312db3 | 359 | local->leave_oper_channel_time = jiffies; |
977923b0 | 360 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
361 | local->scan_channel_idx = 0; |
362 | ||
07ef03ee | 363 | ieee80211_offchannel_stop_vifs(local, true); |
a80f7c0b | 364 | |
3ac64bee | 365 | ieee80211_configure_filter(local); |
f3b85252 | 366 | |
59bdf3b0 BG |
367 | /* We need to set power level at maximum rate for scanning. */ |
368 | ieee80211_hw_config(local, 0); | |
369 | ||
42935eca | 370 | ieee80211_queue_delayed_work(&local->hw, |
07ef03ee | 371 | &local->scan_work, 0); |
f3b85252 JB |
372 | |
373 | return 0; | |
374 | } | |
375 | ||
133d40f9 SG |
376 | static bool ieee80211_can_scan(struct ieee80211_local *local, |
377 | struct ieee80211_sub_if_data *sdata) | |
378 | { | |
379 | if (!list_empty(&local->work_list)) | |
380 | return false; | |
381 | ||
382 | if (sdata->vif.type == NL80211_IFTYPE_STATION && | |
383 | sdata->u.mgd.flags & (IEEE80211_STA_BEACON_POLL | | |
384 | IEEE80211_STA_CONNECTION_POLL)) | |
385 | return false; | |
386 | ||
387 | return true; | |
388 | } | |
389 | ||
390 | void ieee80211_run_deferred_scan(struct ieee80211_local *local) | |
391 | { | |
392 | lockdep_assert_held(&local->mtx); | |
393 | ||
394 | if (!local->scan_req || local->scanning) | |
395 | return; | |
396 | ||
397 | if (!ieee80211_can_scan(local, local->scan_sdata)) | |
398 | return; | |
399 | ||
400 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, | |
401 | round_jiffies_relative(0)); | |
402 | } | |
f3b85252 JB |
403 | |
404 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
405 | struct cfg80211_scan_request *req) | |
406 | { | |
407 | struct ieee80211_local *local = sdata->local; | |
f3b85252 JB |
408 | int rc; |
409 | ||
e229f844 SG |
410 | lockdep_assert_held(&local->mtx); |
411 | ||
f3b85252 JB |
412 | if (local->scan_req) |
413 | return -EBUSY; | |
414 | ||
133d40f9 | 415 | if (!ieee80211_can_scan(local, sdata)) { |
6e7e6213 | 416 | /* wait for the work to finish/time out */ |
c0ce77b8 JB |
417 | local->scan_req = req; |
418 | local->scan_sdata = sdata; | |
419 | return 0; | |
420 | } | |
421 | ||
f3b85252 JB |
422 | if (local->ops->hw_scan) { |
423 | u8 *ies; | |
f3b85252 | 424 | |
4d36ec58 JB |
425 | local->hw_scan_req = kmalloc( |
426 | sizeof(*local->hw_scan_req) + | |
427 | req->n_channels * sizeof(req->channels[0]) + | |
428 | 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + | |
429 | req->ie_len, GFP_KERNEL); | |
430 | if (!local->hw_scan_req) | |
f3b85252 JB |
431 | return -ENOMEM; |
432 | ||
4d36ec58 JB |
433 | local->hw_scan_req->ssids = req->ssids; |
434 | local->hw_scan_req->n_ssids = req->n_ssids; | |
435 | ies = (u8 *)local->hw_scan_req + | |
436 | sizeof(*local->hw_scan_req) + | |
437 | req->n_channels * sizeof(req->channels[0]); | |
438 | local->hw_scan_req->ie = ies; | |
439 | ||
440 | local->hw_scan_band = 0; | |
6e7e6213 JL |
441 | |
442 | /* | |
443 | * After allocating local->hw_scan_req, we must | |
444 | * go through until ieee80211_prep_hw_scan(), so | |
445 | * anything that might be changed here and leave | |
446 | * this function early must not go after this | |
447 | * allocation. | |
448 | */ | |
f3b85252 JB |
449 | } |
450 | ||
451 | local->scan_req = req; | |
452 | local->scan_sdata = sdata; | |
453 | ||
f3b85252 | 454 | if (local->ops->hw_scan) |
fbe9c429 | 455 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 456 | else |
fbe9c429 | 457 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
6e7e6213 | 458 | |
5cff20e6 | 459 | ieee80211_recalc_idle(local); |
f3b85252 | 460 | |
4d36ec58 JB |
461 | if (local->ops->hw_scan) { |
462 | WARN_ON(!ieee80211_prep_hw_scan(local)); | |
a060bbfe | 463 | rc = drv_hw_scan(local, sdata, local->hw_scan_req); |
4d36ec58 | 464 | } else |
f3b85252 JB |
465 | rc = ieee80211_start_sw_scan(local); |
466 | ||
f3b85252 | 467 | if (rc) { |
4d36ec58 JB |
468 | kfree(local->hw_scan_req); |
469 | local->hw_scan_req = NULL; | |
fbe9c429 | 470 | local->scanning = 0; |
f3b85252 | 471 | |
5cff20e6 JB |
472 | ieee80211_recalc_idle(local); |
473 | ||
f3b85252 JB |
474 | local->scan_req = NULL; |
475 | local->scan_sdata = NULL; | |
476 | } | |
477 | ||
478 | return rc; | |
479 | } | |
480 | ||
df13cce5 HS |
481 | static unsigned long |
482 | ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) | |
483 | { | |
484 | /* | |
485 | * TODO: channel switching also consumes quite some time, | |
486 | * add that delay as well to get a better estimation | |
487 | */ | |
488 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) | |
489 | return IEEE80211_PASSIVE_CHANNEL_TIME; | |
490 | return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; | |
491 | } | |
492 | ||
e229f844 SG |
493 | static void ieee80211_scan_state_decision(struct ieee80211_local *local, |
494 | unsigned long *next_delay) | |
7d3be3cc | 495 | { |
142b9f50 | 496 | bool associated = false; |
df13cce5 HS |
497 | bool tx_empty = true; |
498 | bool bad_latency; | |
499 | bool listen_int_exceeded; | |
500 | unsigned long min_beacon_int = 0; | |
142b9f50 | 501 | struct ieee80211_sub_if_data *sdata; |
df13cce5 | 502 | struct ieee80211_channel *next_chan; |
142b9f50 | 503 | |
df13cce5 HS |
504 | /* |
505 | * check if at least one STA interface is associated, | |
506 | * check if at least one STA interface has pending tx frames | |
507 | * and grab the lowest used beacon interval | |
508 | */ | |
142b9f50 HS |
509 | mutex_lock(&local->iflist_mtx); |
510 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 511 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
512 | continue; |
513 | ||
514 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
515 | if (sdata->u.mgd.associated) { | |
516 | associated = true; | |
df13cce5 HS |
517 | |
518 | if (sdata->vif.bss_conf.beacon_int < | |
519 | min_beacon_int || min_beacon_int == 0) | |
520 | min_beacon_int = | |
521 | sdata->vif.bss_conf.beacon_int; | |
522 | ||
523 | if (!qdisc_all_tx_empty(sdata->dev)) { | |
524 | tx_empty = false; | |
525 | break; | |
526 | } | |
142b9f50 HS |
527 | } |
528 | } | |
529 | } | |
530 | mutex_unlock(&local->iflist_mtx); | |
531 | ||
b23b025f BG |
532 | next_chan = local->scan_req->channels[local->scan_channel_idx]; |
533 | ||
a80f7c0b | 534 | /* |
07ef03ee JB |
535 | * we're currently scanning a different channel, let's |
536 | * see if we can scan another channel without interfering | |
537 | * with the current traffic situation. | |
538 | * | |
539 | * Since we don't know if the AP has pending frames for us | |
540 | * we can only check for our tx queues and use the current | |
541 | * pm_qos requirements for rx. Hence, if no tx traffic occurs | |
542 | * at all we will scan as many channels in a row as the pm_qos | |
543 | * latency allows us to. Additionally we also check for the | |
544 | * currently negotiated listen interval to prevent losing | |
545 | * frames unnecessarily. | |
546 | * | |
547 | * Otherwise switch back to the operating channel. | |
a80f7c0b | 548 | */ |
a80f7c0b | 549 | |
07ef03ee JB |
550 | bad_latency = time_after(jiffies + |
551 | ieee80211_scan_get_channel_time(next_chan), | |
552 | local->leave_oper_channel_time + | |
553 | usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY))); | |
df13cce5 | 554 | |
07ef03ee JB |
555 | listen_int_exceeded = time_after(jiffies + |
556 | ieee80211_scan_get_channel_time(next_chan), | |
557 | local->leave_oper_channel_time + | |
558 | usecs_to_jiffies(min_beacon_int * 1024) * | |
559 | local->hw.conf.listen_interval); | |
142b9f50 | 560 | |
07ef03ee JB |
561 | if (associated && (!tx_empty || bad_latency || listen_int_exceeded)) |
562 | local->next_scan_state = SCAN_SUSPEND; | |
563 | else | |
564 | local->next_scan_state = SCAN_SET_CHANNEL; | |
142b9f50 | 565 | |
07ef03ee | 566 | *next_delay = 0; |
142b9f50 HS |
567 | } |
568 | ||
2fb3f028 HS |
569 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
570 | unsigned long *next_delay) | |
571 | { | |
572 | int skip; | |
573 | struct ieee80211_channel *chan; | |
2fb3f028 | 574 | |
7d3be3cc HS |
575 | skip = 0; |
576 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
577 | ||
584991dc | 578 | local->scan_channel = chan; |
b23b025f | 579 | |
07ef03ee JB |
580 | if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) |
581 | skip = 1; | |
7d3be3cc | 582 | |
7d3be3cc HS |
583 | /* advance state machine to next channel/band */ |
584 | local->scan_channel_idx++; | |
585 | ||
0ee9c13c HS |
586 | if (skip) { |
587 | /* if we skip this channel return to the decision state */ | |
588 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 589 | return; |
0ee9c13c | 590 | } |
7d3be3cc HS |
591 | |
592 | /* | |
593 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
594 | * (which unfortunately doesn't say _why_ step a) is done, | |
595 | * but it waits for the probe delay or until a frame is | |
596 | * received - and the received frame would update the NAV). | |
597 | * For now, we do not support waiting until a frame is | |
598 | * received. | |
599 | * | |
600 | * In any case, it is not necessary for a passive scan. | |
601 | */ | |
602 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
603 | !local->scan_req->n_ssids) { | |
604 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 605 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 606 | return; |
7d3be3cc HS |
607 | } |
608 | ||
2fb3f028 | 609 | /* active scan, send probes */ |
7d3be3cc | 610 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 611 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
612 | } |
613 | ||
614 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
615 | unsigned long *next_delay) | |
616 | { | |
617 | int i; | |
618 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
85a237fe | 619 | enum ieee80211_band band = local->hw.conf.channel->band; |
7d3be3cc HS |
620 | |
621 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
622 | ieee80211_send_probe_req( | |
623 | sdata, NULL, | |
624 | local->scan_req->ssids[i].ssid, | |
625 | local->scan_req->ssids[i].ssid_len, | |
a806c558 | 626 | local->scan_req->ie, local->scan_req->ie_len, |
aad14ceb RM |
627 | local->scan_req->rates[band], false, |
628 | local->scan_req->no_cck); | |
7d3be3cc HS |
629 | |
630 | /* | |
631 | * After sending probe requests, wait for probe responses | |
632 | * on the channel. | |
633 | */ | |
634 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 635 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
636 | } |
637 | ||
07ef03ee JB |
638 | static void ieee80211_scan_state_suspend(struct ieee80211_local *local, |
639 | unsigned long *next_delay) | |
640 | { | |
641 | /* switch back to the operating channel */ | |
642 | local->scan_channel = NULL; | |
643 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
644 | ||
645 | /* | |
646 | * Re-enable vifs and beaconing. Leave PS | |
647 | * in off-channel state..will put that back | |
648 | * on-channel at the end of scanning. | |
649 | */ | |
e76aadc5 | 650 | ieee80211_offchannel_return(local, false); |
07ef03ee JB |
651 | |
652 | *next_delay = HZ / 5; | |
653 | /* afterwards, resume scan & go to next channel */ | |
654 | local->next_scan_state = SCAN_RESUME; | |
655 | } | |
656 | ||
657 | static void ieee80211_scan_state_resume(struct ieee80211_local *local, | |
658 | unsigned long *next_delay) | |
659 | { | |
660 | /* PS already is in off-channel mode */ | |
661 | ieee80211_offchannel_stop_vifs(local, false); | |
662 | ||
663 | if (local->ops->flush) { | |
664 | drv_flush(local, false); | |
665 | *next_delay = 0; | |
666 | } else | |
667 | *next_delay = HZ / 10; | |
668 | ||
669 | /* remember when we left the operating channel */ | |
670 | local->leave_oper_channel_time = jiffies; | |
671 | ||
672 | /* advance to the next channel to be scanned */ | |
de2ee84d | 673 | local->next_scan_state = SCAN_SET_CHANNEL; |
07ef03ee JB |
674 | } |
675 | ||
c2b13452 | 676 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
677 | { |
678 | struct ieee80211_local *local = | |
679 | container_of(work, struct ieee80211_local, scan_work.work); | |
d07bfd8b | 680 | struct ieee80211_sub_if_data *sdata; |
0a51b27e | 681 | unsigned long next_delay = 0; |
d07bfd8b | 682 | bool aborted, hw_scan; |
0a51b27e | 683 | |
259b62e3 | 684 | mutex_lock(&local->mtx); |
8789d459 | 685 | |
d07bfd8b JB |
686 | sdata = local->scan_sdata; |
687 | ||
259b62e3 | 688 | if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { |
8789d459 | 689 | aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); |
259b62e3 | 690 | goto out_complete; |
8789d459 JB |
691 | } |
692 | ||
259b62e3 SG |
693 | if (!sdata || !local->scan_req) |
694 | goto out; | |
f3b85252 | 695 | |
fbe9c429 | 696 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
697 | struct cfg80211_scan_request *req = local->scan_req; |
698 | int rc; | |
699 | ||
700 | local->scan_req = NULL; | |
15db0b7f | 701 | local->scan_sdata = NULL; |
f3b85252 JB |
702 | |
703 | rc = __ieee80211_start_scan(sdata, req); | |
259b62e3 | 704 | if (rc) { |
3aed49ef SG |
705 | /* need to complete scan in cfg80211 */ |
706 | local->scan_req = req; | |
259b62e3 SG |
707 | aborted = true; |
708 | goto out_complete; | |
709 | } else | |
710 | goto out; | |
f3b85252 JB |
711 | } |
712 | ||
5bc75728 JB |
713 | /* |
714 | * Avoid re-scheduling when the sdata is going away. | |
715 | */ | |
9607e6b6 | 716 | if (!ieee80211_sdata_running(sdata)) { |
259b62e3 SG |
717 | aborted = true; |
718 | goto out_complete; | |
f3b85252 | 719 | } |
0a51b27e | 720 | |
f502d09b HS |
721 | /* |
722 | * as long as no delay is required advance immediately | |
723 | * without scheduling a new work | |
724 | */ | |
725 | do { | |
c29acf20 RM |
726 | if (!ieee80211_sdata_running(sdata)) { |
727 | aborted = true; | |
728 | goto out_complete; | |
729 | } | |
730 | ||
977923b0 | 731 | switch (local->next_scan_state) { |
2fb3f028 | 732 | case SCAN_DECISION: |
e229f844 SG |
733 | /* if no more bands/channels left, complete scan */ |
734 | if (local->scan_channel_idx >= local->scan_req->n_channels) { | |
735 | aborted = false; | |
736 | goto out_complete; | |
737 | } | |
738 | ieee80211_scan_state_decision(local, &next_delay); | |
f502d09b | 739 | break; |
2fb3f028 HS |
740 | case SCAN_SET_CHANNEL: |
741 | ieee80211_scan_state_set_channel(local, &next_delay); | |
742 | break; | |
f502d09b HS |
743 | case SCAN_SEND_PROBE: |
744 | ieee80211_scan_state_send_probe(local, &next_delay); | |
745 | break; | |
07ef03ee JB |
746 | case SCAN_SUSPEND: |
747 | ieee80211_scan_state_suspend(local, &next_delay); | |
142b9f50 | 748 | break; |
07ef03ee JB |
749 | case SCAN_RESUME: |
750 | ieee80211_scan_state_resume(local, &next_delay); | |
142b9f50 | 751 | break; |
f502d09b HS |
752 | } |
753 | } while (next_delay == 0); | |
0a51b27e | 754 | |
42935eca | 755 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
d07bfd8b | 756 | goto out; |
259b62e3 SG |
757 | |
758 | out_complete: | |
e229f844 | 759 | hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
d07bfd8b | 760 | __ieee80211_scan_completed(&local->hw, aborted, hw_scan); |
259b62e3 SG |
761 | out: |
762 | mutex_unlock(&local->mtx); | |
0a51b27e JB |
763 | } |
764 | ||
f3b85252 JB |
765 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
766 | struct cfg80211_scan_request *req) | |
0a51b27e | 767 | { |
f3b85252 | 768 | int res; |
de95a54b | 769 | |
a1699b75 | 770 | mutex_lock(&sdata->local->mtx); |
f3b85252 | 771 | res = __ieee80211_start_scan(sdata, req); |
a1699b75 | 772 | mutex_unlock(&sdata->local->mtx); |
0a51b27e | 773 | |
f3b85252 | 774 | return res; |
0a51b27e JB |
775 | } |
776 | ||
f3b85252 | 777 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
be4a4b6a JB |
778 | const u8 *ssid, u8 ssid_len, |
779 | struct ieee80211_channel *chan) | |
0a51b27e | 780 | { |
0a51b27e | 781 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 782 | int ret = -EBUSY; |
fb63bc41 | 783 | enum ieee80211_band band; |
2a519311 | 784 | |
a1699b75 | 785 | mutex_lock(&local->mtx); |
0a51b27e | 786 | |
f3b85252 JB |
787 | /* busy scanning */ |
788 | if (local->scan_req) | |
789 | goto unlock; | |
9116dd01 | 790 | |
be4a4b6a JB |
791 | /* fill internal scan request */ |
792 | if (!chan) { | |
793 | int i, nchan = 0; | |
794 | ||
795 | for (band = 0; band < IEEE80211_NUM_BANDS; band++) { | |
796 | if (!local->hw.wiphy->bands[band]) | |
797 | continue; | |
798 | for (i = 0; | |
799 | i < local->hw.wiphy->bands[band]->n_channels; | |
800 | i++) { | |
801 | local->int_scan_req->channels[nchan] = | |
802 | &local->hw.wiphy->bands[band]->channels[i]; | |
803 | nchan++; | |
804 | } | |
805 | } | |
806 | ||
807 | local->int_scan_req->n_channels = nchan; | |
808 | } else { | |
809 | local->int_scan_req->channels[0] = chan; | |
810 | local->int_scan_req->n_channels = 1; | |
811 | } | |
812 | ||
813 | local->int_scan_req->ssids = &local->scan_ssid; | |
814 | local->int_scan_req->n_ssids = 1; | |
5ba63533 JB |
815 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
816 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 817 | |
5ba63533 | 818 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 | 819 | unlock: |
a1699b75 | 820 | mutex_unlock(&local->mtx); |
f3b85252 | 821 | return ret; |
0a51b27e | 822 | } |
5bb644a0 | 823 | |
4136c422 SG |
824 | /* |
825 | * Only call this function when a scan can't be queued -- under RTNL. | |
826 | */ | |
5bb644a0 JB |
827 | void ieee80211_scan_cancel(struct ieee80211_local *local) |
828 | { | |
5bb644a0 | 829 | /* |
b856439b | 830 | * We are canceling software scan, or deferred scan that was not |
4136c422 SG |
831 | * yet really started (see __ieee80211_start_scan ). |
832 | * | |
833 | * Regarding hardware scan: | |
834 | * - we can not call __ieee80211_scan_completed() as when | |
835 | * SCAN_HW_SCANNING bit is set this function change | |
836 | * local->hw_scan_req to operate on 5G band, what race with | |
837 | * driver which can use local->hw_scan_req | |
838 | * | |
839 | * - we can not cancel scan_work since driver can schedule it | |
840 | * by ieee80211_scan_completed(..., true) to finish scan | |
841 | * | |
b856439b EP |
842 | * Hence we only call the cancel_hw_scan() callback, but the low-level |
843 | * driver is still responsible for calling ieee80211_scan_completed() | |
844 | * after the scan was completed/aborted. | |
5bb644a0 | 845 | */ |
4136c422 | 846 | |
a1699b75 | 847 | mutex_lock(&local->mtx); |
b856439b EP |
848 | if (!local->scan_req) |
849 | goto out; | |
850 | ||
851 | if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { | |
852 | if (local->ops->cancel_hw_scan) | |
853 | drv_cancel_hw_scan(local, local->scan_sdata); | |
854 | goto out; | |
4136c422 | 855 | } |
b856439b EP |
856 | |
857 | /* | |
858 | * If the work is currently running, it must be blocked on | |
859 | * the mutex, but we'll set scan_sdata = NULL and it'll | |
860 | * simply exit once it acquires the mutex. | |
861 | */ | |
862 | cancel_delayed_work(&local->scan_work); | |
863 | /* and clean up */ | |
864 | __ieee80211_scan_completed(&local->hw, true, false); | |
865 | out: | |
d07bfd8b | 866 | mutex_unlock(&local->mtx); |
5bb644a0 | 867 | } |
79f460ca LC |
868 | |
869 | int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, | |
870 | struct cfg80211_sched_scan_request *req) | |
871 | { | |
872 | struct ieee80211_local *local = sdata->local; | |
873 | int ret, i; | |
874 | ||
875 | mutex_lock(&sdata->local->mtx); | |
876 | ||
877 | if (local->sched_scanning) { | |
878 | ret = -EBUSY; | |
879 | goto out; | |
880 | } | |
881 | ||
882 | if (!local->ops->sched_scan_start) { | |
883 | ret = -ENOTSUPP; | |
884 | goto out; | |
885 | } | |
886 | ||
887 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { | |
888 | local->sched_scan_ies.ie[i] = kzalloc(2 + | |
889 | IEEE80211_MAX_SSID_LEN + | |
1186980d LC |
890 | local->scan_ies_len + |
891 | req->ie_len, | |
79f460ca LC |
892 | GFP_KERNEL); |
893 | if (!local->sched_scan_ies.ie[i]) { | |
894 | ret = -ENOMEM; | |
895 | goto out_free; | |
896 | } | |
897 | ||
898 | local->sched_scan_ies.len[i] = | |
899 | ieee80211_build_preq_ies(local, | |
900 | local->sched_scan_ies.ie[i], | |
901 | req->ie, req->ie_len, i, | |
902 | (u32) -1, 0); | |
903 | } | |
904 | ||
905 | ret = drv_sched_scan_start(local, sdata, req, | |
906 | &local->sched_scan_ies); | |
907 | if (ret == 0) { | |
908 | local->sched_scanning = true; | |
909 | goto out; | |
910 | } | |
911 | ||
912 | out_free: | |
913 | while (i > 0) | |
914 | kfree(local->sched_scan_ies.ie[--i]); | |
915 | out: | |
916 | mutex_unlock(&sdata->local->mtx); | |
917 | return ret; | |
918 | } | |
919 | ||
85a9994a | 920 | int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata) |
79f460ca LC |
921 | { |
922 | struct ieee80211_local *local = sdata->local; | |
923 | int ret = 0, i; | |
924 | ||
925 | mutex_lock(&sdata->local->mtx); | |
926 | ||
927 | if (!local->ops->sched_scan_stop) { | |
928 | ret = -ENOTSUPP; | |
929 | goto out; | |
930 | } | |
931 | ||
932 | if (local->sched_scanning) { | |
933 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
934 | kfree(local->sched_scan_ies.ie[i]); | |
935 | ||
85a9994a | 936 | drv_sched_scan_stop(local, sdata); |
79f460ca LC |
937 | local->sched_scanning = false; |
938 | } | |
79f460ca LC |
939 | out: |
940 | mutex_unlock(&sdata->local->mtx); | |
941 | ||
942 | return ret; | |
943 | } | |
944 | ||
945 | void ieee80211_sched_scan_results(struct ieee80211_hw *hw) | |
946 | { | |
947 | struct ieee80211_local *local = hw_to_local(hw); | |
948 | ||
949 | trace_api_sched_scan_results(local); | |
950 | ||
951 | cfg80211_sched_scan_results(hw->wiphy); | |
952 | } | |
953 | EXPORT_SYMBOL(ieee80211_sched_scan_results); | |
954 | ||
85a9994a LC |
955 | void ieee80211_sched_scan_stopped_work(struct work_struct *work) |
956 | { | |
957 | struct ieee80211_local *local = | |
958 | container_of(work, struct ieee80211_local, | |
959 | sched_scan_stopped_work); | |
960 | int i; | |
961 | ||
962 | mutex_lock(&local->mtx); | |
963 | ||
964 | if (!local->sched_scanning) { | |
965 | mutex_unlock(&local->mtx); | |
966 | return; | |
967 | } | |
968 | ||
969 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
970 | kfree(local->sched_scan_ies.ie[i]); | |
971 | ||
972 | local->sched_scanning = false; | |
973 | ||
974 | mutex_unlock(&local->mtx); | |
975 | ||
976 | cfg80211_sched_scan_stopped(local->hw.wiphy); | |
977 | } | |
978 | ||
79f460ca LC |
979 | void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) |
980 | { | |
981 | struct ieee80211_local *local = hw_to_local(hw); | |
982 | ||
983 | trace_api_sched_scan_stopped(local); | |
984 | ||
85a9994a | 985 | ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work); |
79f460ca LC |
986 | } |
987 | EXPORT_SYMBOL(ieee80211_sched_scan_stopped); |