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 | |
c2b13452 | 32 | struct ieee80211_bss * |
5484e237 JB |
33 | ieee80211_rx_bss_get(struct ieee80211_local *local, u8 *bssid, int freq, |
34 | u8 *ssid, u8 ssid_len) | |
35 | { | |
0c1ad2ca JB |
36 | struct cfg80211_bss *cbss; |
37 | ||
38 | cbss = cfg80211_get_bss(local->hw.wiphy, | |
39 | ieee80211_get_channel(local->hw.wiphy, freq), | |
40 | bssid, ssid, ssid_len, 0, 0); | |
41 | if (!cbss) | |
42 | return NULL; | |
43 | return (void *)cbss->priv; | |
5484e237 JB |
44 | } |
45 | ||
00d3f14c | 46 | static void ieee80211_rx_bss_free(struct cfg80211_bss *cbss) |
5484e237 | 47 | { |
0c1ad2ca | 48 | struct ieee80211_bss *bss = (void *)cbss->priv; |
5484e237 | 49 | |
5484e237 JB |
50 | kfree(bss_mesh_id(bss)); |
51 | kfree(bss_mesh_cfg(bss)); | |
5484e237 JB |
52 | } |
53 | ||
54 | void ieee80211_rx_bss_put(struct ieee80211_local *local, | |
c2b13452 | 55 | struct ieee80211_bss *bss) |
5484e237 | 56 | { |
0c1ad2ca JB |
57 | if (!bss) |
58 | return; | |
59 | cfg80211_put_bss(container_of((void *)bss, struct cfg80211_bss, priv)); | |
5484e237 JB |
60 | } |
61 | ||
ab13315a KV |
62 | static bool is_uapsd_supported(struct ieee802_11_elems *elems) |
63 | { | |
64 | u8 qos_info; | |
65 | ||
66 | if (elems->wmm_info && elems->wmm_info_len == 7 | |
67 | && elems->wmm_info[5] == 1) | |
68 | qos_info = elems->wmm_info[6]; | |
69 | else if (elems->wmm_param && elems->wmm_param_len == 24 | |
70 | && elems->wmm_param[5] == 1) | |
71 | qos_info = elems->wmm_param[6]; | |
72 | else | |
73 | /* no valid wmm information or parameter element found */ | |
74 | return false; | |
75 | ||
76 | return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD; | |
77 | } | |
78 | ||
c2b13452 | 79 | struct ieee80211_bss * |
5484e237 JB |
80 | ieee80211_bss_info_update(struct ieee80211_local *local, |
81 | struct ieee80211_rx_status *rx_status, | |
82 | struct ieee80211_mgmt *mgmt, | |
83 | size_t len, | |
84 | struct ieee802_11_elems *elems, | |
2a519311 JB |
85 | struct ieee80211_channel *channel, |
86 | bool beacon) | |
5484e237 | 87 | { |
0c1ad2ca | 88 | struct cfg80211_bss *cbss; |
c2b13452 | 89 | struct ieee80211_bss *bss; |
f0b058b6 | 90 | int clen, srlen; |
2a519311 JB |
91 | s32 signal = 0; |
92 | ||
77965c97 | 93 | if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM) |
2a519311 | 94 | signal = rx_status->signal * 100; |
77965c97 | 95 | else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC) |
2a519311 | 96 | signal = (rx_status->signal * 100) / local->hw.max_signal; |
2a519311 | 97 | |
0c1ad2ca JB |
98 | cbss = cfg80211_inform_bss_frame(local->hw.wiphy, channel, |
99 | mgmt, len, signal, GFP_ATOMIC); | |
5484e237 | 100 | |
0c1ad2ca | 101 | if (!cbss) |
00d3f14c JB |
102 | return NULL; |
103 | ||
0c1ad2ca JB |
104 | cbss->free_priv = ieee80211_rx_bss_free; |
105 | bss = (void *)cbss->priv; | |
5484e237 | 106 | |
fcff4f10 PS |
107 | if (elems->parse_error) { |
108 | if (beacon) | |
109 | bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON; | |
110 | else | |
111 | bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP; | |
112 | } else { | |
113 | if (beacon) | |
114 | bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON; | |
115 | else | |
116 | bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP; | |
117 | } | |
118 | ||
5484e237 | 119 | /* save the ERP value so that it is available at association time */ |
fcff4f10 PS |
120 | if (elems->erp_info && elems->erp_info_len >= 1 && |
121 | (!elems->parse_error || | |
122 | !(bss->valid_data & IEEE80211_BSS_VALID_ERP))) { | |
5484e237 | 123 | bss->erp_value = elems->erp_info[0]; |
3db1cd5c | 124 | bss->has_erp_value = true; |
fcff4f10 PS |
125 | if (!elems->parse_error) |
126 | bss->valid_data |= IEEE80211_BSS_VALID_ERP; | |
5484e237 JB |
127 | } |
128 | ||
fcff4f10 PS |
129 | if (elems->tim && (!elems->parse_error || |
130 | !(bss->valid_data & IEEE80211_BSS_VALID_DTIM))) { | |
5484e237 JB |
131 | struct ieee80211_tim_ie *tim_ie = |
132 | (struct ieee80211_tim_ie *)elems->tim; | |
133 | bss->dtim_period = tim_ie->dtim_period; | |
fcff4f10 PS |
134 | if (!elems->parse_error) |
135 | bss->valid_data |= IEEE80211_BSS_VALID_DTIM; | |
5484e237 JB |
136 | } |
137 | ||
e5b900d2 JB |
138 | /* If the beacon had no TIM IE, or it was invalid, use 1 */ |
139 | if (beacon && !bss->dtim_period) | |
140 | bss->dtim_period = 1; | |
141 | ||
f0b058b6 | 142 | /* replace old supported rates if we get new values */ |
fcff4f10 PS |
143 | if (!elems->parse_error || |
144 | !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) { | |
145 | srlen = 0; | |
146 | if (elems->supp_rates) { | |
147 | clen = IEEE80211_MAX_SUPP_RATES; | |
148 | if (clen > elems->supp_rates_len) | |
149 | clen = elems->supp_rates_len; | |
150 | memcpy(bss->supp_rates, elems->supp_rates, clen); | |
151 | srlen += clen; | |
152 | } | |
153 | if (elems->ext_supp_rates) { | |
154 | clen = IEEE80211_MAX_SUPP_RATES - srlen; | |
155 | if (clen > elems->ext_supp_rates_len) | |
156 | clen = elems->ext_supp_rates_len; | |
157 | memcpy(bss->supp_rates + srlen, elems->ext_supp_rates, | |
158 | clen); | |
159 | srlen += clen; | |
160 | } | |
161 | if (srlen) { | |
162 | bss->supp_rates_len = srlen; | |
163 | if (!elems->parse_error) | |
164 | bss->valid_data |= IEEE80211_BSS_VALID_RATES; | |
165 | } | |
5484e237 | 166 | } |
5484e237 | 167 | |
fcff4f10 PS |
168 | if (!elems->parse_error || |
169 | !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) { | |
170 | bss->wmm_used = elems->wmm_param || elems->wmm_info; | |
171 | bss->uapsd_supported = is_uapsd_supported(elems); | |
172 | if (!elems->parse_error) | |
173 | bss->valid_data |= IEEE80211_BSS_VALID_WMM; | |
174 | } | |
5484e237 JB |
175 | |
176 | if (!beacon) | |
177 | bss->last_probe_resp = jiffies; | |
178 | ||
5484e237 JB |
179 | return bss; |
180 | } | |
0a51b27e | 181 | |
98c8fccf | 182 | ieee80211_rx_result |
f1d58c25 | 183 | ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb) |
98c8fccf | 184 | { |
f1d58c25 | 185 | struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb); |
98c8fccf | 186 | struct ieee80211_mgmt *mgmt; |
c2b13452 | 187 | struct ieee80211_bss *bss; |
98c8fccf JB |
188 | u8 *elements; |
189 | struct ieee80211_channel *channel; | |
190 | size_t baselen; | |
191 | int freq; | |
192 | __le16 fc; | |
193 | bool presp, beacon = false; | |
194 | struct ieee802_11_elems elems; | |
195 | ||
196 | if (skb->len < 2) | |
197 | return RX_DROP_UNUSABLE; | |
198 | ||
199 | mgmt = (struct ieee80211_mgmt *) skb->data; | |
200 | fc = mgmt->frame_control; | |
201 | ||
202 | if (ieee80211_is_ctl(fc)) | |
203 | return RX_CONTINUE; | |
204 | ||
205 | if (skb->len < 24) | |
306fe938 | 206 | return RX_CONTINUE; |
98c8fccf JB |
207 | |
208 | presp = ieee80211_is_probe_resp(fc); | |
209 | if (presp) { | |
210 | /* ignore ProbeResp to foreign address */ | |
888d04df | 211 | if (compare_ether_addr(mgmt->da, sdata->vif.addr)) |
98c8fccf JB |
212 | return RX_DROP_MONITOR; |
213 | ||
214 | presp = true; | |
215 | elements = mgmt->u.probe_resp.variable; | |
216 | baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable); | |
217 | } else { | |
218 | beacon = ieee80211_is_beacon(fc); | |
219 | baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable); | |
220 | elements = mgmt->u.beacon.variable; | |
221 | } | |
222 | ||
223 | if (!presp && !beacon) | |
224 | return RX_CONTINUE; | |
225 | ||
226 | if (baselen > skb->len) | |
227 | return RX_DROP_MONITOR; | |
228 | ||
229 | ieee802_11_parse_elems(elements, skb->len - baselen, &elems); | |
230 | ||
231 | if (elems.ds_params && elems.ds_params_len == 1) | |
59eb21a6 BR |
232 | freq = ieee80211_channel_to_frequency(elems.ds_params[0], |
233 | rx_status->band); | |
98c8fccf JB |
234 | else |
235 | freq = rx_status->freq; | |
236 | ||
237 | channel = ieee80211_get_channel(sdata->local->hw.wiphy, freq); | |
238 | ||
239 | if (!channel || channel->flags & IEEE80211_CHAN_DISABLED) | |
240 | return RX_DROP_MONITOR; | |
241 | ||
242 | bss = ieee80211_bss_info_update(sdata->local, rx_status, | |
243 | mgmt, skb->len, &elems, | |
2a519311 | 244 | channel, beacon); |
d048e503 JM |
245 | if (bss) |
246 | ieee80211_rx_bss_put(sdata->local, bss); | |
98c8fccf | 247 | |
07ef03ee | 248 | if (channel == sdata->local->oper_channel) |
b23b025f BG |
249 | return RX_CONTINUE; |
250 | ||
98c8fccf JB |
251 | dev_kfree_skb(skb); |
252 | return RX_QUEUED; | |
253 | } | |
254 | ||
4d36ec58 JB |
255 | /* return false if no more work */ |
256 | static bool ieee80211_prep_hw_scan(struct ieee80211_local *local) | |
257 | { | |
258 | struct cfg80211_scan_request *req = local->scan_req; | |
259 | enum ieee80211_band band; | |
260 | int i, ielen, n_chans; | |
261 | ||
262 | do { | |
263 | if (local->hw_scan_band == IEEE80211_NUM_BANDS) | |
264 | return false; | |
265 | ||
266 | band = local->hw_scan_band; | |
267 | n_chans = 0; | |
268 | for (i = 0; i < req->n_channels; i++) { | |
269 | if (req->channels[i]->band == band) { | |
270 | local->hw_scan_req->channels[n_chans] = | |
271 | req->channels[i]; | |
272 | n_chans++; | |
273 | } | |
274 | } | |
275 | ||
276 | local->hw_scan_band++; | |
277 | } while (!n_chans); | |
278 | ||
279 | local->hw_scan_req->n_channels = n_chans; | |
280 | ||
281 | ielen = ieee80211_build_preq_ies(local, (u8 *)local->hw_scan_req->ie, | |
8ee31080 | 282 | req->ie, req->ie_len, band, |
85a237fe | 283 | req->rates[band], 0); |
4d36ec58 | 284 | local->hw_scan_req->ie_len = ielen; |
dcd83976 | 285 | local->hw_scan_req->no_cck = req->no_cck; |
4d36ec58 JB |
286 | |
287 | return true; | |
288 | } | |
289 | ||
d07bfd8b | 290 | static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted, |
e229f844 | 291 | bool was_hw_scan) |
0a51b27e JB |
292 | { |
293 | struct ieee80211_local *local = hw_to_local(hw); | |
0a51b27e | 294 | |
e229f844 | 295 | lockdep_assert_held(&local->mtx); |
5bc75728 | 296 | |
6d3560d4 JB |
297 | /* |
298 | * It's ok to abort a not-yet-running scan (that | |
299 | * we have one at all will be verified by checking | |
300 | * local->scan_req next), but not to complete it | |
301 | * successfully. | |
302 | */ | |
303 | if (WARN_ON(!local->scanning && !aborted)) | |
304 | aborted = true; | |
5bc75728 | 305 | |
e229f844 | 306 | if (WARN_ON(!local->scan_req)) |
d07bfd8b | 307 | return; |
de95a54b | 308 | |
4d36ec58 | 309 | if (was_hw_scan && !aborted && ieee80211_prep_hw_scan(local)) { |
6eb11a9a SG |
310 | int rc = drv_hw_scan(local, local->scan_sdata, local->hw_scan_req); |
311 | if (rc == 0) | |
d07bfd8b | 312 | return; |
4d36ec58 JB |
313 | } |
314 | ||
315 | kfree(local->hw_scan_req); | |
316 | local->hw_scan_req = NULL; | |
f3b85252 | 317 | |
5ba63533 | 318 | if (local->scan_req != local->int_scan_req) |
2a519311 JB |
319 | cfg80211_scan_done(local->scan_req, aborted); |
320 | local->scan_req = NULL; | |
15db0b7f | 321 | local->scan_sdata = NULL; |
2a519311 | 322 | |
fbe9c429 | 323 | local->scanning = 0; |
58905ca5 | 324 | local->scan_channel = NULL; |
f3b85252 | 325 | |
07ef03ee JB |
326 | /* Set power back to normal operating levels. */ |
327 | ieee80211_hw_config(local, 0); | |
a0daa0e7 | 328 | |
e229f844 SG |
329 | if (!was_hw_scan) { |
330 | ieee80211_configure_filter(local); | |
331 | drv_sw_scan_complete(local); | |
e76aadc5 | 332 | ieee80211_offchannel_return(local, true); |
e229f844 | 333 | } |
0a51b27e | 334 | |
5cff20e6 | 335 | ieee80211_recalc_idle(local); |
e229f844 | 336 | |
0a51b27e | 337 | ieee80211_mlme_notify_scan_completed(local); |
46900298 | 338 | ieee80211_ibss_notify_scan_completed(local); |
472dbc45 | 339 | ieee80211_mesh_notify_scan_completed(local); |
81ac3462 | 340 | ieee80211_queue_work(&local->hw, &local->work_work); |
0a51b27e | 341 | } |
8789d459 JB |
342 | |
343 | void ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted) | |
344 | { | |
345 | struct ieee80211_local *local = hw_to_local(hw); | |
346 | ||
347 | trace_api_scan_completed(local, aborted); | |
348 | ||
349 | set_bit(SCAN_COMPLETED, &local->scanning); | |
350 | if (aborted) | |
351 | set_bit(SCAN_ABORTED, &local->scanning); | |
352 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0); | |
353 | } | |
0a51b27e JB |
354 | EXPORT_SYMBOL(ieee80211_scan_completed); |
355 | ||
f3b85252 JB |
356 | static int ieee80211_start_sw_scan(struct ieee80211_local *local) |
357 | { | |
f3b85252 JB |
358 | /* |
359 | * Hardware/driver doesn't support hw_scan, so use software | |
360 | * scanning instead. First send a nullfunc frame with power save | |
361 | * bit on so that AP will buffer the frames for us while we are not | |
362 | * listening, then send probe requests to each channel and wait for | |
363 | * the responses. After all channels are scanned, tune back to the | |
364 | * original channel and send a nullfunc frame with power save bit | |
365 | * off to trigger the AP to send us all the buffered frames. | |
366 | * | |
367 | * Note that while local->sw_scanning is true everything else but | |
368 | * nullfunc frames and probe requests will be dropped in | |
369 | * ieee80211_tx_h_check_assoc(). | |
370 | */ | |
24487981 | 371 | drv_sw_scan_start(local); |
f3b85252 | 372 | |
de312db3 | 373 | local->leave_oper_channel_time = jiffies; |
977923b0 | 374 | local->next_scan_state = SCAN_DECISION; |
f3b85252 JB |
375 | local->scan_channel_idx = 0; |
376 | ||
07ef03ee | 377 | ieee80211_offchannel_stop_vifs(local, true); |
a80f7c0b | 378 | |
3ac64bee | 379 | ieee80211_configure_filter(local); |
f3b85252 | 380 | |
59bdf3b0 BG |
381 | /* We need to set power level at maximum rate for scanning. */ |
382 | ieee80211_hw_config(local, 0); | |
383 | ||
42935eca | 384 | ieee80211_queue_delayed_work(&local->hw, |
07ef03ee | 385 | &local->scan_work, 0); |
f3b85252 JB |
386 | |
387 | return 0; | |
388 | } | |
389 | ||
390 | ||
391 | static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata, | |
392 | struct cfg80211_scan_request *req) | |
393 | { | |
394 | struct ieee80211_local *local = sdata->local; | |
f3b85252 JB |
395 | int rc; |
396 | ||
e229f844 SG |
397 | lockdep_assert_held(&local->mtx); |
398 | ||
f3b85252 JB |
399 | if (local->scan_req) |
400 | return -EBUSY; | |
401 | ||
6e7e6213 JL |
402 | if (!list_empty(&local->work_list)) { |
403 | /* wait for the work to finish/time out */ | |
c0ce77b8 JB |
404 | local->scan_req = req; |
405 | local->scan_sdata = sdata; | |
406 | return 0; | |
407 | } | |
408 | ||
f3b85252 JB |
409 | if (local->ops->hw_scan) { |
410 | u8 *ies; | |
f3b85252 | 411 | |
4d36ec58 JB |
412 | local->hw_scan_req = kmalloc( |
413 | sizeof(*local->hw_scan_req) + | |
414 | req->n_channels * sizeof(req->channels[0]) + | |
415 | 2 + IEEE80211_MAX_SSID_LEN + local->scan_ies_len + | |
416 | req->ie_len, GFP_KERNEL); | |
417 | if (!local->hw_scan_req) | |
f3b85252 JB |
418 | return -ENOMEM; |
419 | ||
4d36ec58 JB |
420 | local->hw_scan_req->ssids = req->ssids; |
421 | local->hw_scan_req->n_ssids = req->n_ssids; | |
422 | ies = (u8 *)local->hw_scan_req + | |
423 | sizeof(*local->hw_scan_req) + | |
424 | req->n_channels * sizeof(req->channels[0]); | |
425 | local->hw_scan_req->ie = ies; | |
426 | ||
427 | local->hw_scan_band = 0; | |
6e7e6213 JL |
428 | |
429 | /* | |
430 | * After allocating local->hw_scan_req, we must | |
431 | * go through until ieee80211_prep_hw_scan(), so | |
432 | * anything that might be changed here and leave | |
433 | * this function early must not go after this | |
434 | * allocation. | |
435 | */ | |
f3b85252 JB |
436 | } |
437 | ||
438 | local->scan_req = req; | |
439 | local->scan_sdata = sdata; | |
440 | ||
f3b85252 | 441 | if (local->ops->hw_scan) |
fbe9c429 | 442 | __set_bit(SCAN_HW_SCANNING, &local->scanning); |
f3b85252 | 443 | else |
fbe9c429 | 444 | __set_bit(SCAN_SW_SCANNING, &local->scanning); |
6e7e6213 | 445 | |
5cff20e6 | 446 | ieee80211_recalc_idle(local); |
f3b85252 | 447 | |
4d36ec58 JB |
448 | if (local->ops->hw_scan) { |
449 | WARN_ON(!ieee80211_prep_hw_scan(local)); | |
a060bbfe | 450 | rc = drv_hw_scan(local, sdata, local->hw_scan_req); |
4d36ec58 | 451 | } else |
f3b85252 JB |
452 | rc = ieee80211_start_sw_scan(local); |
453 | ||
f3b85252 | 454 | if (rc) { |
4d36ec58 JB |
455 | kfree(local->hw_scan_req); |
456 | local->hw_scan_req = NULL; | |
fbe9c429 | 457 | local->scanning = 0; |
f3b85252 | 458 | |
5cff20e6 JB |
459 | ieee80211_recalc_idle(local); |
460 | ||
f3b85252 JB |
461 | local->scan_req = NULL; |
462 | local->scan_sdata = NULL; | |
463 | } | |
464 | ||
465 | return rc; | |
466 | } | |
467 | ||
df13cce5 HS |
468 | static unsigned long |
469 | ieee80211_scan_get_channel_time(struct ieee80211_channel *chan) | |
470 | { | |
471 | /* | |
472 | * TODO: channel switching also consumes quite some time, | |
473 | * add that delay as well to get a better estimation | |
474 | */ | |
475 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN) | |
476 | return IEEE80211_PASSIVE_CHANNEL_TIME; | |
477 | return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME; | |
478 | } | |
479 | ||
e229f844 SG |
480 | static void ieee80211_scan_state_decision(struct ieee80211_local *local, |
481 | unsigned long *next_delay) | |
7d3be3cc | 482 | { |
142b9f50 | 483 | bool associated = false; |
df13cce5 HS |
484 | bool tx_empty = true; |
485 | bool bad_latency; | |
486 | bool listen_int_exceeded; | |
487 | unsigned long min_beacon_int = 0; | |
142b9f50 | 488 | struct ieee80211_sub_if_data *sdata; |
df13cce5 | 489 | struct ieee80211_channel *next_chan; |
142b9f50 | 490 | |
df13cce5 HS |
491 | /* |
492 | * check if at least one STA interface is associated, | |
493 | * check if at least one STA interface has pending tx frames | |
494 | * and grab the lowest used beacon interval | |
495 | */ | |
142b9f50 HS |
496 | mutex_lock(&local->iflist_mtx); |
497 | list_for_each_entry(sdata, &local->interfaces, list) { | |
9607e6b6 | 498 | if (!ieee80211_sdata_running(sdata)) |
142b9f50 HS |
499 | continue; |
500 | ||
501 | if (sdata->vif.type == NL80211_IFTYPE_STATION) { | |
502 | if (sdata->u.mgd.associated) { | |
503 | associated = true; | |
df13cce5 HS |
504 | |
505 | if (sdata->vif.bss_conf.beacon_int < | |
506 | min_beacon_int || min_beacon_int == 0) | |
507 | min_beacon_int = | |
508 | sdata->vif.bss_conf.beacon_int; | |
509 | ||
510 | if (!qdisc_all_tx_empty(sdata->dev)) { | |
511 | tx_empty = false; | |
512 | break; | |
513 | } | |
142b9f50 HS |
514 | } |
515 | } | |
516 | } | |
517 | mutex_unlock(&local->iflist_mtx); | |
518 | ||
b23b025f BG |
519 | next_chan = local->scan_req->channels[local->scan_channel_idx]; |
520 | ||
a80f7c0b | 521 | /* |
07ef03ee JB |
522 | * we're currently scanning a different channel, let's |
523 | * see if we can scan another channel without interfering | |
524 | * with the current traffic situation. | |
525 | * | |
526 | * Since we don't know if the AP has pending frames for us | |
527 | * we can only check for our tx queues and use the current | |
528 | * pm_qos requirements for rx. Hence, if no tx traffic occurs | |
529 | * at all we will scan as many channels in a row as the pm_qos | |
530 | * latency allows us to. Additionally we also check for the | |
531 | * currently negotiated listen interval to prevent losing | |
532 | * frames unnecessarily. | |
533 | * | |
534 | * Otherwise switch back to the operating channel. | |
a80f7c0b | 535 | */ |
a80f7c0b | 536 | |
07ef03ee JB |
537 | bad_latency = time_after(jiffies + |
538 | ieee80211_scan_get_channel_time(next_chan), | |
539 | local->leave_oper_channel_time + | |
540 | usecs_to_jiffies(pm_qos_request(PM_QOS_NETWORK_LATENCY))); | |
df13cce5 | 541 | |
07ef03ee JB |
542 | listen_int_exceeded = time_after(jiffies + |
543 | ieee80211_scan_get_channel_time(next_chan), | |
544 | local->leave_oper_channel_time + | |
545 | usecs_to_jiffies(min_beacon_int * 1024) * | |
546 | local->hw.conf.listen_interval); | |
142b9f50 | 547 | |
07ef03ee JB |
548 | if (associated && (!tx_empty || bad_latency || listen_int_exceeded)) |
549 | local->next_scan_state = SCAN_SUSPEND; | |
550 | else | |
551 | local->next_scan_state = SCAN_SET_CHANNEL; | |
142b9f50 | 552 | |
07ef03ee | 553 | *next_delay = 0; |
142b9f50 HS |
554 | } |
555 | ||
2fb3f028 HS |
556 | static void ieee80211_scan_state_set_channel(struct ieee80211_local *local, |
557 | unsigned long *next_delay) | |
558 | { | |
559 | int skip; | |
560 | struct ieee80211_channel *chan; | |
2fb3f028 | 561 | |
7d3be3cc HS |
562 | skip = 0; |
563 | chan = local->scan_req->channels[local->scan_channel_idx]; | |
564 | ||
584991dc | 565 | local->scan_channel = chan; |
b23b025f | 566 | |
07ef03ee JB |
567 | if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL)) |
568 | skip = 1; | |
7d3be3cc | 569 | |
7d3be3cc HS |
570 | /* advance state machine to next channel/band */ |
571 | local->scan_channel_idx++; | |
572 | ||
0ee9c13c HS |
573 | if (skip) { |
574 | /* if we skip this channel return to the decision state */ | |
575 | local->next_scan_state = SCAN_DECISION; | |
2fb3f028 | 576 | return; |
0ee9c13c | 577 | } |
7d3be3cc HS |
578 | |
579 | /* | |
580 | * Probe delay is used to update the NAV, cf. 11.1.3.2.2 | |
581 | * (which unfortunately doesn't say _why_ step a) is done, | |
582 | * but it waits for the probe delay or until a frame is | |
583 | * received - and the received frame would update the NAV). | |
584 | * For now, we do not support waiting until a frame is | |
585 | * received. | |
586 | * | |
587 | * In any case, it is not necessary for a passive scan. | |
588 | */ | |
589 | if (chan->flags & IEEE80211_CHAN_PASSIVE_SCAN || | |
590 | !local->scan_req->n_ssids) { | |
591 | *next_delay = IEEE80211_PASSIVE_CHANNEL_TIME; | |
977923b0 | 592 | local->next_scan_state = SCAN_DECISION; |
2fb3f028 | 593 | return; |
7d3be3cc HS |
594 | } |
595 | ||
2fb3f028 | 596 | /* active scan, send probes */ |
7d3be3cc | 597 | *next_delay = IEEE80211_PROBE_DELAY; |
977923b0 | 598 | local->next_scan_state = SCAN_SEND_PROBE; |
7d3be3cc HS |
599 | } |
600 | ||
601 | static void ieee80211_scan_state_send_probe(struct ieee80211_local *local, | |
602 | unsigned long *next_delay) | |
603 | { | |
604 | int i; | |
605 | struct ieee80211_sub_if_data *sdata = local->scan_sdata; | |
85a237fe | 606 | enum ieee80211_band band = local->hw.conf.channel->band; |
7d3be3cc HS |
607 | |
608 | for (i = 0; i < local->scan_req->n_ssids; i++) | |
609 | ieee80211_send_probe_req( | |
610 | sdata, NULL, | |
611 | local->scan_req->ssids[i].ssid, | |
612 | local->scan_req->ssids[i].ssid_len, | |
a806c558 | 613 | local->scan_req->ie, local->scan_req->ie_len, |
aad14ceb RM |
614 | local->scan_req->rates[band], false, |
615 | local->scan_req->no_cck); | |
7d3be3cc HS |
616 | |
617 | /* | |
618 | * After sending probe requests, wait for probe responses | |
619 | * on the channel. | |
620 | */ | |
621 | *next_delay = IEEE80211_CHANNEL_TIME; | |
977923b0 | 622 | local->next_scan_state = SCAN_DECISION; |
7d3be3cc HS |
623 | } |
624 | ||
07ef03ee JB |
625 | static void ieee80211_scan_state_suspend(struct ieee80211_local *local, |
626 | unsigned long *next_delay) | |
627 | { | |
628 | /* switch back to the operating channel */ | |
629 | local->scan_channel = NULL; | |
630 | ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); | |
631 | ||
632 | /* | |
633 | * Re-enable vifs and beaconing. Leave PS | |
634 | * in off-channel state..will put that back | |
635 | * on-channel at the end of scanning. | |
636 | */ | |
e76aadc5 | 637 | ieee80211_offchannel_return(local, false); |
07ef03ee JB |
638 | |
639 | *next_delay = HZ / 5; | |
640 | /* afterwards, resume scan & go to next channel */ | |
641 | local->next_scan_state = SCAN_RESUME; | |
642 | } | |
643 | ||
644 | static void ieee80211_scan_state_resume(struct ieee80211_local *local, | |
645 | unsigned long *next_delay) | |
646 | { | |
647 | /* PS already is in off-channel mode */ | |
648 | ieee80211_offchannel_stop_vifs(local, false); | |
649 | ||
650 | if (local->ops->flush) { | |
651 | drv_flush(local, false); | |
652 | *next_delay = 0; | |
653 | } else | |
654 | *next_delay = HZ / 10; | |
655 | ||
656 | /* remember when we left the operating channel */ | |
657 | local->leave_oper_channel_time = jiffies; | |
658 | ||
659 | /* advance to the next channel to be scanned */ | |
de2ee84d | 660 | local->next_scan_state = SCAN_SET_CHANNEL; |
07ef03ee JB |
661 | } |
662 | ||
c2b13452 | 663 | void ieee80211_scan_work(struct work_struct *work) |
0a51b27e JB |
664 | { |
665 | struct ieee80211_local *local = | |
666 | container_of(work, struct ieee80211_local, scan_work.work); | |
d07bfd8b | 667 | struct ieee80211_sub_if_data *sdata; |
0a51b27e | 668 | unsigned long next_delay = 0; |
d07bfd8b | 669 | bool aborted, hw_scan; |
0a51b27e | 670 | |
259b62e3 | 671 | mutex_lock(&local->mtx); |
8789d459 | 672 | |
d07bfd8b JB |
673 | sdata = local->scan_sdata; |
674 | ||
259b62e3 | 675 | if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) { |
8789d459 | 676 | aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning); |
259b62e3 | 677 | goto out_complete; |
8789d459 JB |
678 | } |
679 | ||
259b62e3 SG |
680 | if (!sdata || !local->scan_req) |
681 | goto out; | |
f3b85252 | 682 | |
fbe9c429 | 683 | if (local->scan_req && !local->scanning) { |
f3b85252 JB |
684 | struct cfg80211_scan_request *req = local->scan_req; |
685 | int rc; | |
686 | ||
687 | local->scan_req = NULL; | |
15db0b7f | 688 | local->scan_sdata = NULL; |
f3b85252 JB |
689 | |
690 | rc = __ieee80211_start_scan(sdata, req); | |
259b62e3 | 691 | if (rc) { |
3aed49ef SG |
692 | /* need to complete scan in cfg80211 */ |
693 | local->scan_req = req; | |
259b62e3 SG |
694 | aborted = true; |
695 | goto out_complete; | |
696 | } else | |
697 | goto out; | |
f3b85252 JB |
698 | } |
699 | ||
5bc75728 JB |
700 | /* |
701 | * Avoid re-scheduling when the sdata is going away. | |
702 | */ | |
9607e6b6 | 703 | if (!ieee80211_sdata_running(sdata)) { |
259b62e3 SG |
704 | aborted = true; |
705 | goto out_complete; | |
f3b85252 | 706 | } |
0a51b27e | 707 | |
f502d09b HS |
708 | /* |
709 | * as long as no delay is required advance immediately | |
710 | * without scheduling a new work | |
711 | */ | |
712 | do { | |
c29acf20 RM |
713 | if (!ieee80211_sdata_running(sdata)) { |
714 | aborted = true; | |
715 | goto out_complete; | |
716 | } | |
717 | ||
977923b0 | 718 | switch (local->next_scan_state) { |
2fb3f028 | 719 | case SCAN_DECISION: |
e229f844 SG |
720 | /* if no more bands/channels left, complete scan */ |
721 | if (local->scan_channel_idx >= local->scan_req->n_channels) { | |
722 | aborted = false; | |
723 | goto out_complete; | |
724 | } | |
725 | ieee80211_scan_state_decision(local, &next_delay); | |
f502d09b | 726 | break; |
2fb3f028 HS |
727 | case SCAN_SET_CHANNEL: |
728 | ieee80211_scan_state_set_channel(local, &next_delay); | |
729 | break; | |
f502d09b HS |
730 | case SCAN_SEND_PROBE: |
731 | ieee80211_scan_state_send_probe(local, &next_delay); | |
732 | break; | |
07ef03ee JB |
733 | case SCAN_SUSPEND: |
734 | ieee80211_scan_state_suspend(local, &next_delay); | |
142b9f50 | 735 | break; |
07ef03ee JB |
736 | case SCAN_RESUME: |
737 | ieee80211_scan_state_resume(local, &next_delay); | |
142b9f50 | 738 | break; |
f502d09b HS |
739 | } |
740 | } while (next_delay == 0); | |
0a51b27e | 741 | |
42935eca | 742 | ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay); |
d07bfd8b | 743 | goto out; |
259b62e3 SG |
744 | |
745 | out_complete: | |
e229f844 | 746 | hw_scan = test_bit(SCAN_HW_SCANNING, &local->scanning); |
d07bfd8b | 747 | __ieee80211_scan_completed(&local->hw, aborted, hw_scan); |
259b62e3 SG |
748 | out: |
749 | mutex_unlock(&local->mtx); | |
0a51b27e JB |
750 | } |
751 | ||
f3b85252 JB |
752 | int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata, |
753 | struct cfg80211_scan_request *req) | |
0a51b27e | 754 | { |
f3b85252 | 755 | int res; |
de95a54b | 756 | |
a1699b75 | 757 | mutex_lock(&sdata->local->mtx); |
f3b85252 | 758 | res = __ieee80211_start_scan(sdata, req); |
a1699b75 | 759 | mutex_unlock(&sdata->local->mtx); |
0a51b27e | 760 | |
f3b85252 | 761 | return res; |
0a51b27e JB |
762 | } |
763 | ||
f3b85252 | 764 | int ieee80211_request_internal_scan(struct ieee80211_sub_if_data *sdata, |
be4a4b6a JB |
765 | const u8 *ssid, u8 ssid_len, |
766 | struct ieee80211_channel *chan) | |
0a51b27e | 767 | { |
0a51b27e | 768 | struct ieee80211_local *local = sdata->local; |
f3b85252 | 769 | int ret = -EBUSY; |
fb63bc41 | 770 | enum ieee80211_band band; |
2a519311 | 771 | |
a1699b75 | 772 | mutex_lock(&local->mtx); |
0a51b27e | 773 | |
f3b85252 JB |
774 | /* busy scanning */ |
775 | if (local->scan_req) | |
776 | goto unlock; | |
9116dd01 | 777 | |
be4a4b6a JB |
778 | /* fill internal scan request */ |
779 | if (!chan) { | |
780 | int i, nchan = 0; | |
781 | ||
782 | for (band = 0; band < IEEE80211_NUM_BANDS; band++) { | |
783 | if (!local->hw.wiphy->bands[band]) | |
784 | continue; | |
785 | for (i = 0; | |
786 | i < local->hw.wiphy->bands[band]->n_channels; | |
787 | i++) { | |
788 | local->int_scan_req->channels[nchan] = | |
789 | &local->hw.wiphy->bands[band]->channels[i]; | |
790 | nchan++; | |
791 | } | |
792 | } | |
793 | ||
794 | local->int_scan_req->n_channels = nchan; | |
795 | } else { | |
796 | local->int_scan_req->channels[0] = chan; | |
797 | local->int_scan_req->n_channels = 1; | |
798 | } | |
799 | ||
800 | local->int_scan_req->ssids = &local->scan_ssid; | |
801 | local->int_scan_req->n_ssids = 1; | |
5ba63533 JB |
802 | memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN); |
803 | local->int_scan_req->ssids[0].ssid_len = ssid_len; | |
9116dd01 | 804 | |
5ba63533 | 805 | ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req); |
f3b85252 | 806 | unlock: |
a1699b75 | 807 | mutex_unlock(&local->mtx); |
f3b85252 | 808 | return ret; |
0a51b27e | 809 | } |
5bb644a0 | 810 | |
4136c422 SG |
811 | /* |
812 | * Only call this function when a scan can't be queued -- under RTNL. | |
813 | */ | |
5bb644a0 JB |
814 | void ieee80211_scan_cancel(struct ieee80211_local *local) |
815 | { | |
5bb644a0 | 816 | /* |
b856439b | 817 | * We are canceling software scan, or deferred scan that was not |
4136c422 SG |
818 | * yet really started (see __ieee80211_start_scan ). |
819 | * | |
820 | * Regarding hardware scan: | |
821 | * - we can not call __ieee80211_scan_completed() as when | |
822 | * SCAN_HW_SCANNING bit is set this function change | |
823 | * local->hw_scan_req to operate on 5G band, what race with | |
824 | * driver which can use local->hw_scan_req | |
825 | * | |
826 | * - we can not cancel scan_work since driver can schedule it | |
827 | * by ieee80211_scan_completed(..., true) to finish scan | |
828 | * | |
b856439b EP |
829 | * Hence we only call the cancel_hw_scan() callback, but the low-level |
830 | * driver is still responsible for calling ieee80211_scan_completed() | |
831 | * after the scan was completed/aborted. | |
5bb644a0 | 832 | */ |
4136c422 | 833 | |
a1699b75 | 834 | mutex_lock(&local->mtx); |
b856439b EP |
835 | if (!local->scan_req) |
836 | goto out; | |
837 | ||
838 | if (test_bit(SCAN_HW_SCANNING, &local->scanning)) { | |
839 | if (local->ops->cancel_hw_scan) | |
840 | drv_cancel_hw_scan(local, local->scan_sdata); | |
841 | goto out; | |
4136c422 | 842 | } |
b856439b EP |
843 | |
844 | /* | |
845 | * If the work is currently running, it must be blocked on | |
846 | * the mutex, but we'll set scan_sdata = NULL and it'll | |
847 | * simply exit once it acquires the mutex. | |
848 | */ | |
849 | cancel_delayed_work(&local->scan_work); | |
850 | /* and clean up */ | |
851 | __ieee80211_scan_completed(&local->hw, true, false); | |
852 | out: | |
d07bfd8b | 853 | mutex_unlock(&local->mtx); |
5bb644a0 | 854 | } |
79f460ca LC |
855 | |
856 | int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata, | |
857 | struct cfg80211_sched_scan_request *req) | |
858 | { | |
859 | struct ieee80211_local *local = sdata->local; | |
860 | int ret, i; | |
861 | ||
862 | mutex_lock(&sdata->local->mtx); | |
863 | ||
864 | if (local->sched_scanning) { | |
865 | ret = -EBUSY; | |
866 | goto out; | |
867 | } | |
868 | ||
869 | if (!local->ops->sched_scan_start) { | |
870 | ret = -ENOTSUPP; | |
871 | goto out; | |
872 | } | |
873 | ||
874 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) { | |
875 | local->sched_scan_ies.ie[i] = kzalloc(2 + | |
876 | IEEE80211_MAX_SSID_LEN + | |
1186980d LC |
877 | local->scan_ies_len + |
878 | req->ie_len, | |
79f460ca LC |
879 | GFP_KERNEL); |
880 | if (!local->sched_scan_ies.ie[i]) { | |
881 | ret = -ENOMEM; | |
882 | goto out_free; | |
883 | } | |
884 | ||
885 | local->sched_scan_ies.len[i] = | |
886 | ieee80211_build_preq_ies(local, | |
887 | local->sched_scan_ies.ie[i], | |
888 | req->ie, req->ie_len, i, | |
889 | (u32) -1, 0); | |
890 | } | |
891 | ||
892 | ret = drv_sched_scan_start(local, sdata, req, | |
893 | &local->sched_scan_ies); | |
894 | if (ret == 0) { | |
895 | local->sched_scanning = true; | |
896 | goto out; | |
897 | } | |
898 | ||
899 | out_free: | |
900 | while (i > 0) | |
901 | kfree(local->sched_scan_ies.ie[--i]); | |
902 | out: | |
903 | mutex_unlock(&sdata->local->mtx); | |
904 | return ret; | |
905 | } | |
906 | ||
85a9994a | 907 | int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata) |
79f460ca LC |
908 | { |
909 | struct ieee80211_local *local = sdata->local; | |
910 | int ret = 0, i; | |
911 | ||
912 | mutex_lock(&sdata->local->mtx); | |
913 | ||
914 | if (!local->ops->sched_scan_stop) { | |
915 | ret = -ENOTSUPP; | |
916 | goto out; | |
917 | } | |
918 | ||
919 | if (local->sched_scanning) { | |
920 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
921 | kfree(local->sched_scan_ies.ie[i]); | |
922 | ||
85a9994a | 923 | drv_sched_scan_stop(local, sdata); |
79f460ca LC |
924 | local->sched_scanning = false; |
925 | } | |
79f460ca LC |
926 | out: |
927 | mutex_unlock(&sdata->local->mtx); | |
928 | ||
929 | return ret; | |
930 | } | |
931 | ||
932 | void ieee80211_sched_scan_results(struct ieee80211_hw *hw) | |
933 | { | |
934 | struct ieee80211_local *local = hw_to_local(hw); | |
935 | ||
936 | trace_api_sched_scan_results(local); | |
937 | ||
938 | cfg80211_sched_scan_results(hw->wiphy); | |
939 | } | |
940 | EXPORT_SYMBOL(ieee80211_sched_scan_results); | |
941 | ||
85a9994a LC |
942 | void ieee80211_sched_scan_stopped_work(struct work_struct *work) |
943 | { | |
944 | struct ieee80211_local *local = | |
945 | container_of(work, struct ieee80211_local, | |
946 | sched_scan_stopped_work); | |
947 | int i; | |
948 | ||
949 | mutex_lock(&local->mtx); | |
950 | ||
951 | if (!local->sched_scanning) { | |
952 | mutex_unlock(&local->mtx); | |
953 | return; | |
954 | } | |
955 | ||
956 | for (i = 0; i < IEEE80211_NUM_BANDS; i++) | |
957 | kfree(local->sched_scan_ies.ie[i]); | |
958 | ||
959 | local->sched_scanning = false; | |
960 | ||
961 | mutex_unlock(&local->mtx); | |
962 | ||
963 | cfg80211_sched_scan_stopped(local->hw.wiphy); | |
964 | } | |
965 | ||
79f460ca LC |
966 | void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw) |
967 | { | |
968 | struct ieee80211_local *local = hw_to_local(hw); | |
969 | ||
970 | trace_api_sched_scan_stopped(local); | |
971 | ||
85a9994a | 972 | ieee80211_queue_work(&local->hw, &local->sched_scan_stopped_work); |
79f460ca LC |
973 | } |
974 | EXPORT_SYMBOL(ieee80211_sched_scan_stopped); |