1 /*-
2 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28
29 /*
30 * IEEE 802.11 scanning support.
31 */
32 #include "opt_wlan.h"
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/proc.h>
37 #include <sys/kernel.h>
38 #include <sys/condvar.h>
39
40 #include <sys/socket.h>
41
42 #include <net/if.h>
43 #include <net/if_media.h>
44 #include <net/ethernet.h>
45
46 #include <net80211/ieee80211_var.h>
47
48 #include <net/bpf.h>
49
50 struct scan_state {
51 struct ieee80211_scan_state base; /* public state */
52
53 u_int ss_iflags; /* flags used internally */
54 #define ISCAN_MINDWELL 0x0001 /* min dwell time reached */
55 #define ISCAN_DISCARD 0x0002 /* discard rx'd frames */
56 #define ISCAN_CANCEL 0x0004 /* cancel current scan */
57 #define ISCAN_ABORT 0x0008 /* end the scan immediately */
58 unsigned long ss_chanmindwell; /* min dwell on curchan */
59 unsigned long ss_scanend; /* time scan must stop */
60 u_int ss_duration; /* duration for next scan */
61 struct task ss_scan_task; /* scan execution */
62 struct cv ss_scan_cv; /* scan signal */
63 struct callout ss_scan_timer; /* scan timer */
64 };
65 #define SCAN_PRIVATE(ss) ((struct scan_state *) ss)
66
67 /*
68 * Amount of time to go off-channel during a background
69 * scan. This value should be large enough to catch most
70 * ap's but short enough that we can return on-channel
71 * before our listen interval expires.
72 *
73 * XXX tunable
74 * XXX check against configured listen interval
75 */
76 #define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150)
77
78 /*
79 * Roaming-related defaults. RSSI thresholds are as returned by the
80 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
81 * .5M units) or MCS.
82 */
83 /* rssi thresholds */
84 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
85 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
86 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
87 /* transmit rate thresholds */
88 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
89 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
90 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
91 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
92 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
93 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
94
95 static void scan_curchan(struct ieee80211_scan_state *, unsigned long);
96 static void scan_mindwell(struct ieee80211_scan_state *);
97 static void scan_signal(void *);
98 static void scan_task(void *, int);
99
100 MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state");
101
102 void
103 ieee80211_scan_attach(struct ieee80211com *ic)
104 {
105 struct scan_state *ss;
106
107 ss = (struct scan_state *) malloc(sizeof(struct scan_state),
108 M_80211_SCAN, M_NOWAIT | M_ZERO);
109 if (ss == NULL) {
110 ic->ic_scan = NULL;
111 return;
112 }
113 callout_init_mtx(&ss->ss_scan_timer, IEEE80211_LOCK_OBJ(ic), 0);
114 cv_init(&ss->ss_scan_cv, "scan");
115 TASK_INIT(&ss->ss_scan_task, 0, scan_task, ss);
116 ic->ic_scan = &ss->base;
117 ss->base.ss_ic = ic;
118
119 ic->ic_scan_curchan = scan_curchan;
120 ic->ic_scan_mindwell = scan_mindwell;
121 }
122
123 void
124 ieee80211_scan_detach(struct ieee80211com *ic)
125 {
126 struct ieee80211_scan_state *ss = ic->ic_scan;
127
128 if (ss != NULL) {
129 IEEE80211_LOCK(ic);
130 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT;
131 scan_signal(ss);
132 IEEE80211_UNLOCK(ic);
133 ieee80211_draintask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
134 callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer);
135 KASSERT((ic->ic_flags & IEEE80211_F_SCAN) == 0,
136 ("scan still running"));
137 if (ss->ss_ops != NULL) {
138 ss->ss_ops->scan_detach(ss);
139 ss->ss_ops = NULL;
140 }
141 ic->ic_scan = NULL;
142 free(SCAN_PRIVATE(ss), M_80211_SCAN);
143 }
144 }
145
146 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
147 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
148 .rate = ROAM_RATE_11A_DEFAULT },
149 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
150 .rate = ROAM_RATE_11B_DEFAULT },
151 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
152 .rate = ROAM_RATE_11BONLY_DEFAULT },
153 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
154 .rate = ROAM_RATE_11A_DEFAULT },
155 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
156 .rate = ROAM_RATE_11A_DEFAULT },
157 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
158 .rate = ROAM_RATE_11A_DEFAULT },
159 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
160 .rate = ROAM_RATE_HALF_DEFAULT },
161 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
162 .rate = ROAM_RATE_QUARTER_DEFAULT },
163 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
164 .rate = ROAM_MCS_11N_DEFAULT },
165 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
166 .rate = ROAM_MCS_11N_DEFAULT },
167 };
168
169 void
170 ieee80211_scan_vattach(struct ieee80211vap *vap)
171 {
172 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
173 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
174 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
175
176 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
177 memcpy(vap->iv_roamparms, defroam, sizeof(defroam));
178 }
179
180 void
181 ieee80211_scan_vdetach(struct ieee80211vap *vap)
182 {
183 struct ieee80211com *ic = vap->iv_ic;
184 struct ieee80211_scan_state *ss;
185
186 IEEE80211_LOCK(ic);
187 ss = ic->ic_scan;
188 if (ss != NULL && ss->ss_vap == vap) {
189 if (ic->ic_flags & IEEE80211_F_SCAN) {
190 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT;
191 scan_signal(ss);
192 }
193 if (ss->ss_ops != NULL) {
194 ss->ss_ops->scan_detach(ss);
195 ss->ss_ops = NULL;
196 }
197 ss->ss_vap = NULL;
198 }
199 IEEE80211_UNLOCK(ic);
200 }
201
202 /*
203 * Simple-minded scanner module support.
204 */
205 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
206 "wlan_scan_sta", /* IEEE80211_M_IBSS */
207 "wlan_scan_sta", /* IEEE80211_M_STA */
208 "wlan_scan_wds", /* IEEE80211_M_WDS */
209 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
210 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
211 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
212 "wlan_scan_sta", /* IEEE80211_M_MBSS */
213 };
214 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
215
216 const struct ieee80211_scanner *
217 ieee80211_scanner_get(enum ieee80211_opmode mode)
218 {
219 if (mode >= IEEE80211_OPMODE_MAX)
220 return NULL;
221 if (scanners[mode] == NULL)
222 ieee80211_load_module(scan_modnames[mode]);
223 return scanners[mode];
224 }
225
226 void
227 ieee80211_scanner_register(enum ieee80211_opmode mode,
228 const struct ieee80211_scanner *scan)
229 {
230 if (mode >= IEEE80211_OPMODE_MAX)
231 return;
232 scanners[mode] = scan;
233 }
234
235 void
236 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
237 const struct ieee80211_scanner *scan)
238 {
239 if (mode >= IEEE80211_OPMODE_MAX)
240 return;
241 if (scanners[mode] == scan)
242 scanners[mode] = NULL;
243 }
244
245 void
246 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
247 {
248 int m;
249
250 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
251 if (scanners[m] == scan)
252 scanners[m] = NULL;
253 }
254
255 /*
256 * Update common scanner state to reflect the current
257 * operating mode. This is called when the state machine
258 * is transitioned to RUN state w/o scanning--e.g. when
259 * operating in monitor mode. The purpose of this is to
260 * ensure later callbacks find ss_ops set to properly
261 * reflect current operating mode.
262 */
263 static void
264 scan_update_locked(struct ieee80211vap *vap,
265 const struct ieee80211_scanner *scan)
266 {
267 struct ieee80211com *ic = vap->iv_ic;
268 struct ieee80211_scan_state *ss = ic->ic_scan;
269
270 IEEE80211_LOCK_ASSERT(ic);
271
272 #ifdef IEEE80211_DEBUG
273 if (ss->ss_vap != vap || ss->ss_ops != scan) {
274 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
275 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
276 __func__,
277 ss->ss_vap != NULL ?
278 ss->ss_vap->iv_ifp->if_xname : "none",
279 ss->ss_vap != NULL ?
280 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
281 vap->iv_ifp->if_xname,
282 ieee80211_opmode_name[vap->iv_opmode]);
283 }
284 #endif
285 ss->ss_vap = vap;
286 if (ss->ss_ops != scan) {
287 /*
288 * Switch scanners; detach old, attach new. Special
289 * case where a single scan module implements multiple
290 * policies by using different scan ops but a common
291 * core. We assume if the old and new attach methods
292 * are identical then it's ok to just change ss_ops
293 * and not flush the internal state of the module.
294 */
295 if (scan == NULL || ss->ss_ops == NULL ||
296 ss->ss_ops->scan_attach != scan->scan_attach) {
297 if (ss->ss_ops != NULL)
298 ss->ss_ops->scan_detach(ss);
299 if (scan != NULL && !scan->scan_attach(ss)) {
300 /* XXX attach failure */
301 /* XXX stat+msg */
302 scan = NULL;
303 }
304 }
305 ss->ss_ops = scan;
306 }
307 }
308
309 static char
310 channel_type(const struct ieee80211_channel *c)
311 {
312 if (IEEE80211_IS_CHAN_ST(c))
313 return 'S';
314 if (IEEE80211_IS_CHAN_108A(c))
315 return 'T';
316 if (IEEE80211_IS_CHAN_108G(c))
317 return 'G';
318 if (IEEE80211_IS_CHAN_HT(c))
319 return 'n';
320 if (IEEE80211_IS_CHAN_A(c))
321 return 'a';
322 if (IEEE80211_IS_CHAN_ANYG(c))
323 return 'g';
324 if (IEEE80211_IS_CHAN_B(c))
325 return 'b';
326 return 'f';
327 }
328
329 void
330 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
331 {
332 struct ieee80211com *ic = ss->ss_ic;
333 const char *sep;
334 int i;
335
336 sep = "";
337 for (i = ss->ss_next; i < ss->ss_last; i++) {
338 const struct ieee80211_channel *c = ss->ss_chans[i];
339
340 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
341 channel_type(c));
342 sep = ", ";
343 }
344 }
345
346 #ifdef IEEE80211_DEBUG
347 static void
348 scan_dump(struct ieee80211_scan_state *ss)
349 {
350 struct ieee80211vap *vap = ss->ss_vap;
351
352 if_printf(vap->iv_ifp, "scan set ");
353 ieee80211_scan_dump_channels(ss);
354 printf(" dwell min %lums max %lums\n",
355 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
356 }
357 #endif /* IEEE80211_DEBUG */
358
359 static void
360 copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
361 int nssid, const struct ieee80211_scan_ssid ssids[])
362 {
363 if (nssid > IEEE80211_SCAN_MAX_SSID) {
364 /* XXX printf */
365 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
366 "%s: too many ssid %d, ignoring all of them\n",
367 __func__, nssid);
368 return;
369 }
370 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
371 ss->ss_nssid = nssid;
372 }
373
374 /*
375 * Start a scan unless one is already going.
376 */
377 static int
378 start_scan_locked(const struct ieee80211_scanner *scan,
379 struct ieee80211vap *vap, int flags, u_int duration,
380 u_int mindwell, u_int maxdwell,
381 u_int nssid, const struct ieee80211_scan_ssid ssids[])
382 {
383 struct ieee80211com *ic = vap->iv_ic;
384 struct ieee80211_scan_state *ss = ic->ic_scan;
385
386 IEEE80211_LOCK_ASSERT(ic);
387
388 if (ic->ic_flags & IEEE80211_F_CSAPENDING) {
389 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
390 "%s: scan inhibited by pending channel change\n", __func__);
391 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
392 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
393 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n"
394 , __func__
395 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
396 , duration, mindwell, maxdwell
397 , ieee80211_phymode_name[vap->iv_des_mode]
398 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
399 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
400 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
401 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : ""
402 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
403 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
404 );
405
406 scan_update_locked(vap, scan);
407 if (ss->ss_ops != NULL) {
408 if ((flags & IEEE80211_SCAN_NOSSID) == 0)
409 copy_ssid(vap, ss, nssid, ssids);
410
411 /* NB: top 4 bits for internal use */
412 ss->ss_flags = flags & 0xfff;
413 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
414 vap->iv_stats.is_scan_active++;
415 else
416 vap->iv_stats.is_scan_passive++;
417 if (flags & IEEE80211_SCAN_FLUSH)
418 ss->ss_ops->scan_flush(ss);
419
420 /* NB: flush frames rx'd before 1st channel change */
421 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
422 SCAN_PRIVATE(ss)->ss_duration = duration;
423 ss->ss_next = 0;
424 ss->ss_mindwell = mindwell;
425 ss->ss_maxdwell = maxdwell;
426 /* NB: scan_start must be before the scan runtask */
427 ss->ss_ops->scan_start(ss, vap);
428 #ifdef IEEE80211_DEBUG
429 if (ieee80211_msg_scan(vap))
430 scan_dump(ss);
431 #endif /* IEEE80211_DEBUG */
432 ic->ic_flags |= IEEE80211_F_SCAN;
433 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
434 }
435 } else {
436 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
437 "%s: %s scan already in progress\n", __func__,
438 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
439 }
440 return (ic->ic_flags & IEEE80211_F_SCAN);
441 }
442
443 /*
444 * Start a scan unless one is already going.
445 */
446 int
447 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
448 u_int duration, u_int mindwell, u_int maxdwell,
449 u_int nssid, const struct ieee80211_scan_ssid ssids[])
450 {
451 struct ieee80211com *ic = vap->iv_ic;
452 const struct ieee80211_scanner *scan;
453 int result;
454
455 scan = ieee80211_scanner_get(vap->iv_opmode);
456 if (scan == NULL) {
457 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
458 "%s: no scanner support for %s mode\n",
459 __func__, ieee80211_opmode_name[vap->iv_opmode]);
460 /* XXX stat */
461 return 0;
462 }
463
464 IEEE80211_LOCK(ic);
465 result = start_scan_locked(scan, vap, flags, duration,
466 mindwell, maxdwell, nssid, ssids);
467 IEEE80211_UNLOCK(ic);
468
469 return result;
470 }
471
472 /*
473 * Check the scan cache for an ap/channel to use; if that
474 * fails then kick off a new scan.
475 */
476 int
477 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
478 u_int duration, u_int mindwell, u_int maxdwell,
479 u_int nssid, const struct ieee80211_scan_ssid ssids[])
480 {
481 struct ieee80211com *ic = vap->iv_ic;
482 struct ieee80211_scan_state *ss = ic->ic_scan;
483 const struct ieee80211_scanner *scan;
484 int result;
485
486 scan = ieee80211_scanner_get(vap->iv_opmode);
487 if (scan == NULL) {
488 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
489 "%s: no scanner support for %s mode\n",
490 __func__, vap->iv_opmode);
491 /* XXX stat */
492 return 0;
493 }
494
495 /*
496 * Check if there's a list of scan candidates already.
497 * XXX want more than the ap we're currently associated with
498 */
499
500 IEEE80211_LOCK(ic);
501 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
502 "%s: %s scan, %s%s%s%s%s\n"
503 , __func__
504 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
505 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
506 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
507 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
508 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
509 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
510 );
511
512 if (ss->ss_ops != scan) {
513 /* XXX re-use cache contents? e.g. adhoc<->sta */
514 flags |= IEEE80211_SCAN_FLUSH;
515 }
516 scan_update_locked(vap, scan);
517 if (ss->ss_ops != NULL) {
518 /* XXX verify ss_ops matches vap->iv_opmode */
519 if ((flags & IEEE80211_SCAN_NOSSID) == 0) {
520 /*
521 * Update the ssid list and mark flags so if
522 * we call start_scan it doesn't duplicate work.
523 */
524 copy_ssid(vap, ss, nssid, ssids);
525 flags |= IEEE80211_SCAN_NOSSID;
526 }
527 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 &&
528 (flags & IEEE80211_SCAN_FLUSH) == 0 &&
529 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
530 /*
531 * We're not currently scanning and the cache is
532 * deemed hot enough to consult. Lock out others
533 * by marking IEEE80211_F_SCAN while we decide if
534 * something is already in the scan cache we can
535 * use. Also discard any frames that might come
536 * in while temporarily marked as scanning.
537 */
538 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
539 ic->ic_flags |= IEEE80211_F_SCAN;
540
541 /* NB: need to use supplied flags in check */
542 ss->ss_flags = flags & 0xff;
543 result = ss->ss_ops->scan_end(ss, vap);
544
545 ic->ic_flags &= ~IEEE80211_F_SCAN;
546 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD;
547 if (result) {
548 ieee80211_notify_scan_done(vap);
549 IEEE80211_UNLOCK(ic);
550 return 1;
551 }
552 }
553 }
554 result = start_scan_locked(scan, vap, flags, duration,
555 mindwell, maxdwell, nssid, ssids);
556 IEEE80211_UNLOCK(ic);
557
558 return result;
559 }
560
561 /*
562 * Check the scan cache for an ap/channel to use; if that fails
563 * then kick off a scan using the current settings.
564 */
565 int
566 ieee80211_check_scan_current(struct ieee80211vap *vap)
567 {
568 return ieee80211_check_scan(vap,
569 IEEE80211_SCAN_ACTIVE,
570 IEEE80211_SCAN_FOREVER, 0, 0,
571 vap->iv_des_nssid, vap->iv_des_ssid);
572 }
573
574 /*
575 * Restart a previous scan. If the previous scan completed
576 * then we start again using the existing channel list.
577 */
578 int
579 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
580 {
581 struct ieee80211com *ic = vap->iv_ic;
582 struct ieee80211_scan_state *ss = ic->ic_scan;
583 const struct ieee80211_scanner *scan;
584
585 scan = ieee80211_scanner_get(vap->iv_opmode);
586 if (scan == NULL) {
587 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
588 "%s: no scanner support for %s mode\n",
589 __func__, vap->iv_opmode);
590 /* XXX stat */
591 return 0;
592 }
593
594 IEEE80211_LOCK(ic);
595 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
596 u_int duration;
597 /*
598 * Go off-channel for a fixed interval that is large
599 * enough to catch most ap's but short enough that
600 * we can return on-channel before our listen interval
601 * expires.
602 */
603 duration = IEEE80211_SCAN_OFFCHANNEL;
604
605 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
606 "%s: %s scan, ticks %u duration %lu\n", __func__,
607 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive",
608 ticks, duration);
609
610 scan_update_locked(vap, scan);
611 if (ss->ss_ops != NULL) {
612 ss->ss_vap = vap;
613 /*
614 * A background scan does not select a new sta; it
615 * just refreshes the scan cache. Also, indicate
616 * the scan logic should follow the beacon schedule:
617 * we go off-channel and scan for a while, then
618 * return to the bss channel to receive a beacon,
619 * then go off-channel again. All during this time
620 * we notify the ap we're in power save mode. When
621 * the scan is complete we leave power save mode.
622 * If any beacon indicates there are frames pending
623 * for us then we drop out of power save mode
624 * (and background scan) automatically by way of the
625 * usual sta power save logic.
626 */
627 ss->ss_flags |= IEEE80211_SCAN_NOPICK
628 | IEEE80211_SCAN_BGSCAN
629 | flags
630 ;
631 /* if previous scan completed, restart */
632 if (ss->ss_next >= ss->ss_last) {
633 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
634 vap->iv_stats.is_scan_active++;
635 else
636 vap->iv_stats.is_scan_passive++;
637 /*
638 * NB: beware of the scan cache being flushed;
639 * if the channel list is empty use the
640 * scan_start method to populate it.
641 */
642 ss->ss_next = 0;
643 if (ss->ss_last != 0)
644 ss->ss_ops->scan_restart(ss, vap);
645 else {
646 ss->ss_ops->scan_start(ss, vap);
647 #ifdef IEEE80211_DEBUG
648 if (ieee80211_msg_scan(vap))
649 scan_dump(ss);
650 #endif /* IEEE80211_DEBUG */
651 }
652 }
653 /* NB: flush frames rx'd before 1st channel change */
654 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
655 SCAN_PRIVATE(ss)->ss_duration = duration;
656 ss->ss_maxdwell = duration;
657 ic->ic_flags |= IEEE80211_F_SCAN;
658 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN;
659 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
660 } else {
661 /* XXX msg+stat */
662 }
663 } else {
664 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
665 "%s: %s scan already in progress\n", __func__,
666 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
667 }
668 IEEE80211_UNLOCK(ic);
669
670 /* NB: racey, does it matter? */
671 return (ic->ic_flags & IEEE80211_F_SCAN);
672 }
673
674 /*
675 * Cancel any scan currently going on for the specified vap.
676 */
677 void
678 ieee80211_cancel_scan(struct ieee80211vap *vap)
679 {
680 struct ieee80211com *ic = vap->iv_ic;
681 struct ieee80211_scan_state *ss = ic->ic_scan;
682
683 IEEE80211_LOCK(ic);
684 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
685 ss->ss_vap == vap &&
686 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
687 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
688 "%s: cancel %s scan\n", __func__,
689 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
690 "active" : "passive");
691
692 /* clear bg scan NOPICK and mark cancel request */
693 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
694 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
695 /* wake up the scan task */
696 scan_signal(ss);
697 }
698 IEEE80211_UNLOCK(ic);
699 }
700
701 /*
702 * Cancel any scan currently going on.
703 */
704 void
705 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
706 {
707 struct ieee80211com *ic = vap->iv_ic;
708 struct ieee80211_scan_state *ss = ic->ic_scan;
709
710 IEEE80211_LOCK(ic);
711 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
712 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
713 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
714 "%s: cancel %s scan\n", __func__,
715 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
716 "active" : "passive");
717
718 /* clear bg scan NOPICK and mark cancel request */
719 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
720 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
721 /* wake up the scan task */
722 scan_signal(ss);
723 }
724 IEEE80211_UNLOCK(ic);
725 }
726
727 /*
728 * Public access to scan_next for drivers that manage
729 * scanning themselves (e.g. for firmware-based devices).
730 */
731 void
732 ieee80211_scan_next(struct ieee80211vap *vap)
733 {
734 struct ieee80211com *ic = vap->iv_ic;
735 struct ieee80211_scan_state *ss = ic->ic_scan;
736
737 /* wake up the scan task */
738 IEEE80211_LOCK(ic);
739 scan_signal(ss);
740 IEEE80211_UNLOCK(ic);
741 }
742
743 /*
744 * Public access to scan_next for drivers that are not able to scan single
745 * channels (e.g. for firmware-based devices).
746 */
747 void
748 ieee80211_scan_done(struct ieee80211vap *vap)
749 {
750 struct ieee80211com *ic = vap->iv_ic;
751 struct ieee80211_scan_state *ss;
752
753 IEEE80211_LOCK(ic);
754 ss = ic->ic_scan;
755 ss->ss_next = ss->ss_last; /* all channels are complete */
756 scan_signal(ss);
757 IEEE80211_UNLOCK(ic);
758 }
759
760 /*
761 * Probe the curent channel, if allowed, while scanning.
762 * If the channel is not marked passive-only then send
763 * a probe request immediately. Otherwise mark state and
764 * listen for beacons on the channel; if we receive something
765 * then we'll transmit a probe request.
766 */
767 void
768 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
769 {
770 struct ieee80211com *ic = vap->iv_ic;
771 struct ieee80211_scan_state *ss = ic->ic_scan;
772 struct ifnet *ifp = vap->iv_ifp;
773 int i;
774
775 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
776 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
777 return;
778 }
779 /*
780 * Send directed probe requests followed by any
781 * broadcast probe request.
782 * XXX remove dependence on ic/vap->iv_bss
783 */
784 for (i = 0; i < ss->ss_nssid; i++)
785 ieee80211_send_probereq(vap->iv_bss,
786 vap->iv_myaddr, ifp->if_broadcastaddr,
787 ifp->if_broadcastaddr,
788 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len);
789 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0)
790 ieee80211_send_probereq(vap->iv_bss,
791 vap->iv_myaddr, ifp->if_broadcastaddr,
792 ifp->if_broadcastaddr,
793 "", 0);
794 }
795
796 /*
797 * Scan curchan. If this is an active scan and the channel
798 * is not marked passive then send probe request frame(s).
799 * Arrange for the channel change after maxdwell ticks.
800 */
801 static void
802 scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
803 {
804 struct ieee80211vap *vap = ss->ss_vap;
805
806 IEEE80211_LOCK(vap->iv_ic);
807 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
808 ieee80211_probe_curchan(vap, 0);
809 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
810 maxdwell, scan_signal, ss);
811 IEEE80211_UNLOCK(vap->iv_ic);
812 }
813
814 static void
815 scan_signal(void *arg)
816 {
817 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
818
819 IEEE80211_LOCK_ASSERT(ss->ss_ic);
820
821 cv_signal(&SCAN_PRIVATE(ss)->ss_scan_cv);
822 }
823
824 /*
825 * Handle mindwell requirements completed; initiate a channel
826 * change to the next channel asap.
827 */
828 static void
829 scan_mindwell(struct ieee80211_scan_state *ss)
830 {
831 struct ieee80211com *ic = ss->ss_ic;
832
833 IEEE80211_LOCK(ic);
834 scan_signal(ss);
835 IEEE80211_UNLOCK(ic);
836 }
837
838 static void
839 scan_task(void *arg, int pending)
840 {
841 #define ISCAN_REP (ISCAN_MINDWELL | ISCAN_DISCARD)
842 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
843 struct ieee80211vap *vap = ss->ss_vap;
844 struct ieee80211com *ic = ss->ss_ic;
845 struct ieee80211_channel *chan;
846 unsigned long maxdwell, scanend;
847 int scandone = 0;
848
849 IEEE80211_LOCK(ic);
850 if (vap == NULL || (ic->ic_flags & IEEE80211_F_SCAN) == 0 ||
851 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)) {
852 /* Cancelled before we started */
853 goto done;
854 }
855
856 if (ss->ss_next == ss->ss_last) {
857 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
858 "%s: no channels to scan\n", __func__);
859 goto done;
860 }
861
862 if (vap->iv_opmode == IEEE80211_M_STA &&
863 vap->iv_state == IEEE80211_S_RUN) {
864 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
865 /* Enable station power save mode */
866 ieee80211_sta_pwrsave(vap, 1);
867 /*
868 * Use an 1ms delay so the null data frame has a chance
869 * to go out.
870 * XXX Should use M_TXCB mechanism to eliminate this.
871 */
872 cv_timedwait(&SCAN_PRIVATE(ss)->ss_scan_cv,
873 IEEE80211_LOCK_OBJ(ic), hz / 1000);
874 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
875 goto done;
876 }
877 }
878
879 scanend = ticks + SCAN_PRIVATE(ss)->ss_duration;
880 IEEE80211_UNLOCK(ic);
881 ic->ic_scan_start(ic); /* notify driver */
882 IEEE80211_LOCK(ic);
883
884 for (;;) {
885 scandone = (ss->ss_next >= ss->ss_last) ||
886 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0;
887 if (scandone || (ss->ss_flags & IEEE80211_SCAN_GOTPICK) ||
888 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) ||
889 time_after(ticks + ss->ss_mindwell, scanend))
890 break;
891
892 chan = ss->ss_chans[ss->ss_next++];
893
894 /*
895 * Watch for truncation due to the scan end time.
896 */
897 if (time_after(ticks + ss->ss_maxdwell, scanend))
898 maxdwell = scanend - ticks;
899 else
900 maxdwell = ss->ss_maxdwell;
901
902 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
903 "%s: chan %3d%c -> %3d%c [%s, dwell min %lums max %lums]\n",
904 __func__,
905 ieee80211_chan2ieee(ic, ic->ic_curchan),
906 channel_type(ic->ic_curchan),
907 ieee80211_chan2ieee(ic, chan), channel_type(chan),
908 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
909 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
910 "active" : "passive",
911 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(maxdwell));
912
913 /*
914 * Potentially change channel and phy mode.
915 */
916 ic->ic_curchan = chan;
917 ic->ic_rt = ieee80211_get_ratetable(chan);
918 IEEE80211_UNLOCK(ic);
919 /*
920 * Perform the channel change and scan unlocked so the driver
921 * may sleep. Once set_channel returns the hardware has
922 * completed the channel change.
923 */
924 ic->ic_set_channel(ic);
925 ieee80211_radiotap_chan_change(ic);
926
927 /*
928 * Scan curchan. Drivers for "intelligent hardware"
929 * override ic_scan_curchan to tell the device to do
930 * the work. Otherwise we manage the work outselves;
931 * sending a probe request (as needed), and arming the
932 * timeout to switch channels after maxdwell ticks.
933 *
934 * scan_curchan should only pause for the time required to
935 * prepare/initiate the hardware for the scan (if at all), the
936 * below condvar is used to sleep for the channels dwell time
937 * and allows it to be signalled for abort.
938 */
939 ic->ic_scan_curchan(ss, maxdwell);
940 IEEE80211_LOCK(ic);
941
942 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell;
943 /* clear mindwell lock and initial channel change flush */
944 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
945
946 if ((SCAN_PRIVATE(ss)->ss_iflags & (ISCAN_CANCEL|ISCAN_ABORT)))
947 continue;
948
949 /* Wait to be signalled to scan the next channel */
950 cv_wait(&SCAN_PRIVATE(ss)->ss_scan_cv, IEEE80211_LOCK_OBJ(ic));
951 }
952 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
953 goto done;
954
955 IEEE80211_UNLOCK(ic);
956 ic->ic_scan_end(ic); /* notify driver */
957 IEEE80211_LOCK(ic);
958
959 /*
960 * Record scan complete time. Note that we also do
961 * this when canceled so any background scan will
962 * not be restarted for a while.
963 */
964 if (scandone)
965 ic->ic_lastscan = ticks;
966 /* return to the bss channel */
967 if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
968 ic->ic_curchan != ic->ic_bsschan) {
969 ieee80211_setupcurchan(ic, ic->ic_bsschan);
970 IEEE80211_UNLOCK(ic);
971 ic->ic_set_channel(ic);
972 ieee80211_radiotap_chan_change(ic);
973 IEEE80211_LOCK(ic);
974 }
975 /* clear internal flags and any indication of a pick */
976 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
977 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK;
978
979 /*
980 * If not canceled and scan completed, do post-processing.
981 * If the callback function returns 0, then it wants to
982 * continue/restart scanning. Unfortunately we needed to
983 * notify the driver to end the scan above to avoid having
984 * rx frames alter the scan candidate list.
985 */
986 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 &&
987 !ss->ss_ops->scan_end(ss, vap) &&
988 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 &&
989 time_before(ticks + ss->ss_mindwell, scanend)) {
990 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
991 "%s: done, restart "
992 "[ticks %u, dwell min %lu scanend %lu]\n",
993 __func__,
994 ticks, ss->ss_mindwell, scanend);
995 ss->ss_next = 0; /* reset to begining */
996 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
997 vap->iv_stats.is_scan_active++;
998 else
999 vap->iv_stats.is_scan_passive++;
1000
1001 ss->ss_ops->scan_restart(ss, vap); /* XXX? */
1002 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
1003 IEEE80211_UNLOCK(ic);
1004 return;
1005 }
1006
1007 /* past here, scandone is ``true'' if not in bg mode */
1008 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0)
1009 scandone = 1;
1010
1011 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1012 "%s: %s, [ticks %u, dwell min %lu scanend %lu]\n",
1013 __func__, scandone ? "done" : "stopped",
1014 ticks, ss->ss_mindwell, scanend);
1015
1016 /*
1017 * Clear the SCAN bit first in case frames are
1018 * pending on the station power save queue. If
1019 * we defer this then the dispatch of the frames
1020 * may generate a request to cancel scanning.
1021 */
1022 done:
1023 ic->ic_flags &= ~IEEE80211_F_SCAN;
1024 /*
1025 * Drop out of power save mode when a scan has
1026 * completed. If this scan was prematurely terminated
1027 * because it is a background scan then don't notify
1028 * the ap; we'll either return to scanning after we
1029 * receive the beacon frame or we'll drop out of power
1030 * save mode because the beacon indicates we have frames
1031 * waiting for us.
1032 */
1033 if (scandone) {
1034 ieee80211_sta_pwrsave(vap, 0);
1035 if (ss->ss_next >= ss->ss_last) {
1036 ieee80211_notify_scan_done(vap);
1037 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN;
1038 }
1039 }
1040 SCAN_PRIVATE(ss)->ss_iflags &= ~(ISCAN_CANCEL|ISCAN_ABORT);
1041 ss->ss_flags &= ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST);
1042 IEEE80211_UNLOCK(ic);
1043 #undef ISCAN_REP
1044 }
1045
1046 #ifdef IEEE80211_DEBUG
1047 static void
1048 dump_country(const uint8_t *ie)
1049 {
1050 const struct ieee80211_country_ie *cie =
1051 (const struct ieee80211_country_ie *) ie;
1052 int i, nbands, schan, nchan;
1053
1054 if (cie->len < 3) {
1055 printf(" <bogus country ie, len %d>", cie->len);
1056 return;
1057 }
1058 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
1059 nbands = (cie->len - 3) / sizeof(cie->band[0]);
1060 for (i = 0; i < nbands; i++) {
1061 schan = cie->band[i].schan;
1062 nchan = cie->band[i].nchan;
1063 if (nchan != 1)
1064 printf(" %u-%u,%u", schan, schan + nchan-1,
1065 cie->band[i].maxtxpwr);
1066 else
1067 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
1068 }
1069 printf("]");
1070 }
1071
1072 static void
1073 dump_probe_beacon(uint8_t subtype, int isnew,
1074 const uint8_t mac[IEEE80211_ADDR_LEN],
1075 const struct ieee80211_scanparams *sp, int rssi)
1076 {
1077
1078 printf("[%s] %s%s on chan %u (bss chan %u) ",
1079 ether_sprintf(mac), isnew ? "new " : "",
1080 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1081 sp->chan, sp->bchan);
1082 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1083 printf(" rssi %d\n", rssi);
1084
1085 if (isnew) {
1086 printf("[%s] caps 0x%x bintval %u erp 0x%x",
1087 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1088 if (sp->country != NULL)
1089 dump_country(sp->country);
1090 printf("\n");
1091 }
1092 }
1093 #endif /* IEEE80211_DEBUG */
1094
1095 /*
1096 * Process a beacon or probe response frame.
1097 */
1098 void
1099 ieee80211_add_scan(struct ieee80211vap *vap,
1100 const struct ieee80211_scanparams *sp,
1101 const struct ieee80211_frame *wh,
1102 int subtype, int rssi, int noise)
1103 {
1104 struct ieee80211com *ic = vap->iv_ic;
1105 struct ieee80211_scan_state *ss = ic->ic_scan;
1106
1107 /* XXX locking */
1108 /*
1109 * Frames received during startup are discarded to avoid
1110 * using scan state setup on the initial entry to the timer
1111 * callback. This can occur because the device may enable
1112 * rx prior to our doing the initial channel change in the
1113 * timer routine.
1114 */
1115 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD)
1116 return;
1117 #ifdef IEEE80211_DEBUG
1118 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN))
1119 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi);
1120 #endif
1121 if (ss->ss_ops != NULL &&
1122 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise)) {
1123 /*
1124 * If we've reached the min dwell time terminate
1125 * the timer so we'll switch to the next channel.
1126 */
1127 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 &&
1128 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) {
1129 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1130 "%s: chan %3d%c min dwell met (%u > %lu)\n",
1131 __func__,
1132 ieee80211_chan2ieee(ic, ic->ic_curchan),
1133 channel_type(ic->ic_curchan),
1134 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell);
1135 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL;
1136 /*
1137 * NB: trigger at next clock tick or wait for the
1138 * hardware.
1139 */
1140 ic->ic_scan_mindwell(ss);
1141 }
1142 }
1143 }
1144
1145 /*
1146 * Timeout/age scan cache entries; called from sta timeout
1147 * timer (XXX should be self-contained).
1148 */
1149 void
1150 ieee80211_scan_timeout(struct ieee80211com *ic)
1151 {
1152 struct ieee80211_scan_state *ss = ic->ic_scan;
1153
1154 if (ss->ss_ops != NULL)
1155 ss->ss_ops->scan_age(ss);
1156 }
1157
1158 /*
1159 * Mark a scan cache entry after a successful associate.
1160 */
1161 void
1162 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
1163 {
1164 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1165
1166 if (ss->ss_ops != NULL) {
1167 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
1168 mac, "%s", __func__);
1169 ss->ss_ops->scan_assoc_success(ss, mac);
1170 }
1171 }
1172
1173 /*
1174 * Demerit a scan cache entry after failing to associate.
1175 */
1176 void
1177 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
1178 const uint8_t mac[], int reason)
1179 {
1180 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1181
1182 if (ss->ss_ops != NULL) {
1183 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
1184 "%s: reason %u", __func__, reason);
1185 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
1186 }
1187 }
1188
1189 /*
1190 * Iterate over the contents of the scan cache.
1191 */
1192 void
1193 ieee80211_scan_iterate(struct ieee80211vap *vap,
1194 ieee80211_scan_iter_func *f, void *arg)
1195 {
1196 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1197
1198 if (ss->ss_ops != NULL)
1199 ss->ss_ops->scan_iterate(ss, f, arg);
1200 }
1201
1202 /*
1203 * Flush the contents of the scan cache.
1204 */
1205 void
1206 ieee80211_scan_flush(struct ieee80211vap *vap)
1207 {
1208 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1209
1210 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
1211 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
1212 ss->ss_ops->scan_flush(ss);
1213 }
1214 }
1215
1216 /*
1217 * Check the scan cache for an ap/channel to use; if that
1218 * fails then kick off a new scan.
1219 */
1220 struct ieee80211_channel *
1221 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
1222 {
1223 struct ieee80211_scan_state *ss = ic->ic_scan;
1224
1225 IEEE80211_LOCK_ASSERT(ic);
1226
1227 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
1228 /* XXX printf? */
1229 return NULL;
1230 }
1231 if (ss->ss_ops->scan_pickchan == NULL) {
1232 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
1233 "%s: scan module does not support picking a channel, "
1234 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
1235 return NULL;
1236 }
1237 return ss->ss_ops->scan_pickchan(ss, flags);
1238 }
Cache object: 390517ed839438d0183be96b78e50438
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