xref: /freebsd/sys/net80211/ieee80211_scan.c (revision b00ab754)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 /*
32  * IEEE 802.11 scanning support.
33  */
34 #include "opt_wlan.h"
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/proc.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/condvar.h>
42 
43 #include <sys/socket.h>
44 
45 #include <net/if.h>
46 #include <net/if_var.h>
47 #include <net/if_media.h>
48 #include <net/ethernet.h>
49 
50 #include <net80211/ieee80211_var.h>
51 
52 /* XXX until it's implemented as attach ops */
53 #include <net80211/ieee80211_scan_sw.h>
54 
55 #include <net/bpf.h>
56 
57 /*
58  * Roaming-related defaults.  RSSI thresholds are as returned by the
59  * driver (.5dBm).  Transmit rate thresholds are IEEE rate codes (i.e
60  * .5M units) or MCS.
61  */
62 /* rssi thresholds */
63 #define	ROAM_RSSI_11A_DEFAULT		14	/* 11a bss */
64 #define	ROAM_RSSI_11B_DEFAULT		14	/* 11b bss */
65 #define	ROAM_RSSI_11BONLY_DEFAULT	14	/* 11b-only bss */
66 /* transmit rate thresholds */
67 #define	ROAM_RATE_11A_DEFAULT		2*12	/* 11a bss */
68 #define	ROAM_RATE_11B_DEFAULT		2*5	/* 11b bss */
69 #define	ROAM_RATE_11BONLY_DEFAULT	2*1	/* 11b-only bss */
70 #define	ROAM_RATE_HALF_DEFAULT		2*6	/* half-width 11a/g bss */
71 #define	ROAM_RATE_QUARTER_DEFAULT	2*3	/* quarter-width 11a/g bss */
72 #define	ROAM_MCS_11N_DEFAULT		(1 | IEEE80211_RATE_MCS) /* 11n bss */
73 #define	ROAM_MCS_11AC_DEFAULT		(1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
74 
75 void
76 ieee80211_scan_attach(struct ieee80211com *ic)
77 {
78 	/*
79 	 * If there's no scan method pointer, attach the
80 	 * swscan set as a default.
81 	 */
82 	if (ic->ic_scan_methods == NULL)
83 		ieee80211_swscan_attach(ic);
84 	else
85 		ic->ic_scan_methods->sc_attach(ic);
86 }
87 
88 void
89 ieee80211_scan_detach(struct ieee80211com *ic)
90 {
91 
92 	/*
93 	 * Ideally we'd do the ss_ops detach call here;
94 	 * but then sc_detach() would need to be split in two.
95 	 *
96 	 * I'll do that later.
97 	 */
98 	ic->ic_scan_methods->sc_detach(ic);
99 }
100 
101 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
102 	[IEEE80211_MODE_11A]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
103 				    .rate = ROAM_RATE_11A_DEFAULT },
104 	[IEEE80211_MODE_11G]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
105 				    .rate = ROAM_RATE_11B_DEFAULT },
106 	[IEEE80211_MODE_11B]	= { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
107 				    .rate = ROAM_RATE_11BONLY_DEFAULT },
108 	[IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
109 				    .rate = ROAM_RATE_11A_DEFAULT },
110 	[IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
111 				    .rate = ROAM_RATE_11A_DEFAULT },
112 	[IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
113 				    .rate = ROAM_RATE_11A_DEFAULT },
114 	[IEEE80211_MODE_HALF]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
115 				    .rate = ROAM_RATE_HALF_DEFAULT },
116 	[IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
117 				    .rate = ROAM_RATE_QUARTER_DEFAULT },
118 	[IEEE80211_MODE_11NA]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
119 				    .rate = ROAM_MCS_11N_DEFAULT },
120 	[IEEE80211_MODE_11NG]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
121 				    .rate = ROAM_MCS_11N_DEFAULT },
122 	[IEEE80211_MODE_VHT_2GHZ]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
123 				    .rate = ROAM_MCS_11AC_DEFAULT },
124 	[IEEE80211_MODE_VHT_5GHZ]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
125 				    .rate = ROAM_MCS_11AC_DEFAULT },
126 
127 };
128 
129 void
130 ieee80211_scan_vattach(struct ieee80211vap *vap)
131 {
132 	struct ieee80211com *ic = vap->iv_ic;
133 
134 	vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
135 	vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
136 	vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
137 
138 	vap->iv_roaming = IEEE80211_ROAMING_AUTO;
139 	memcpy(vap->iv_roamparms, defroam, sizeof(defroam));
140 
141 	ic->ic_scan_methods->sc_vattach(vap);
142 }
143 
144 void
145 ieee80211_scan_vdetach(struct ieee80211vap *vap)
146 {
147 	struct ieee80211com *ic = vap->iv_ic;
148 	struct ieee80211_scan_state *ss;
149 
150 	IEEE80211_LOCK(ic);
151 	ss = ic->ic_scan;
152 
153 	ic->ic_scan_methods->sc_vdetach(vap);
154 
155 	if (ss != NULL && ss->ss_vap == vap) {
156 		if (ss->ss_ops != NULL) {
157 			ss->ss_ops->scan_detach(ss);
158 			ss->ss_ops = NULL;
159 		}
160 		ss->ss_vap = NULL;
161 	}
162 	IEEE80211_UNLOCK(ic);
163 }
164 
165 /*
166  * Simple-minded scanner module support.
167  */
168 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
169 	"wlan_scan_sta",	/* IEEE80211_M_IBSS */
170 	"wlan_scan_sta",	/* IEEE80211_M_STA */
171 	"wlan_scan_wds",	/* IEEE80211_M_WDS */
172 	"wlan_scan_sta",	/* IEEE80211_M_AHDEMO */
173 	"wlan_scan_ap",		/* IEEE80211_M_HOSTAP */
174 	"wlan_scan_monitor",	/* IEEE80211_M_MONITOR */
175 	"wlan_scan_sta",	/* IEEE80211_M_MBSS */
176 };
177 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
178 
179 const struct ieee80211_scanner *
180 ieee80211_scanner_get(enum ieee80211_opmode mode)
181 {
182 	if (mode >= IEEE80211_OPMODE_MAX)
183 		return NULL;
184 	if (scanners[mode] == NULL)
185 		ieee80211_load_module(scan_modnames[mode]);
186 	return scanners[mode];
187 }
188 
189 void
190 ieee80211_scanner_register(enum ieee80211_opmode mode,
191 	const struct ieee80211_scanner *scan)
192 {
193 	if (mode >= IEEE80211_OPMODE_MAX)
194 		return;
195 	scanners[mode] = scan;
196 }
197 
198 void
199 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
200 	const struct ieee80211_scanner *scan)
201 {
202 	if (mode >= IEEE80211_OPMODE_MAX)
203 		return;
204 	if (scanners[mode] == scan)
205 		scanners[mode] = NULL;
206 }
207 
208 void
209 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
210 {
211 	int m;
212 
213 	for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
214 		if (scanners[m] == scan)
215 			scanners[m] = NULL;
216 }
217 
218 /*
219  * Update common scanner state to reflect the current
220  * operating mode.  This is called when the state machine
221  * is transitioned to RUN state w/o scanning--e.g. when
222  * operating in monitor mode.  The purpose of this is to
223  * ensure later callbacks find ss_ops set to properly
224  * reflect current operating mode.
225  */
226 void
227 ieee80211_scan_update_locked(struct ieee80211vap *vap,
228 	const struct ieee80211_scanner *scan)
229 {
230 	struct ieee80211com *ic = vap->iv_ic;
231 	struct ieee80211_scan_state *ss = ic->ic_scan;
232 
233 	IEEE80211_LOCK_ASSERT(ic);
234 
235 #ifdef IEEE80211_DEBUG
236 	if (ss->ss_vap != vap || ss->ss_ops != scan) {
237 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
238 		    "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
239 		    __func__,
240 		    ss->ss_vap != NULL ?
241 			ss->ss_vap->iv_ifp->if_xname : "none",
242 		    ss->ss_vap != NULL ?
243 			ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
244 		    vap->iv_ifp->if_xname,
245 		    ieee80211_opmode_name[vap->iv_opmode]);
246 	}
247 #endif
248 	ss->ss_vap = vap;
249 	if (ss->ss_ops != scan) {
250 		/*
251 		 * Switch scanners; detach old, attach new.  Special
252 		 * case where a single scan module implements multiple
253 		 * policies by using different scan ops but a common
254 		 * core.  We assume if the old and new attach methods
255 		 * are identical then it's ok to just change ss_ops
256 		 * and not flush the internal state of the module.
257 		 */
258 		if (scan == NULL || ss->ss_ops == NULL ||
259 		    ss->ss_ops->scan_attach != scan->scan_attach) {
260 			if (ss->ss_ops != NULL)
261 				ss->ss_ops->scan_detach(ss);
262 			if (scan != NULL && !scan->scan_attach(ss)) {
263 				/* XXX attach failure */
264 				/* XXX stat+msg */
265 				scan = NULL;
266 			}
267 		}
268 		ss->ss_ops = scan;
269 	}
270 }
271 
272 void
273 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
274 {
275 	struct ieee80211com *ic = ss->ss_ic;
276 	const char *sep;
277 	int i;
278 
279 	sep = "";
280 	for (i = ss->ss_next; i < ss->ss_last; i++) {
281 		const struct ieee80211_channel *c = ss->ss_chans[i];
282 
283 		printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
284 		    ieee80211_channel_type_char(c));
285 		sep = ", ";
286 	}
287 }
288 
289 #ifdef IEEE80211_DEBUG
290 void
291 ieee80211_scan_dump(struct ieee80211_scan_state *ss)
292 {
293 	struct ieee80211vap *vap = ss->ss_vap;
294 
295 	if_printf(vap->iv_ifp, "scan set ");
296 	ieee80211_scan_dump_channels(ss);
297 	printf(" dwell min %lums max %lums\n",
298 	    ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
299 }
300 #endif /* IEEE80211_DEBUG */
301 
302 void
303 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
304 	int nssid, const struct ieee80211_scan_ssid ssids[])
305 {
306 	if (nssid > IEEE80211_SCAN_MAX_SSID) {
307 		/* XXX printf */
308 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
309 		    "%s: too many ssid %d, ignoring all of them\n",
310 		    __func__, nssid);
311 		return;
312 	}
313 	memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
314 	ss->ss_nssid = nssid;
315 }
316 
317 /*
318  * Start a scan unless one is already going.
319  */
320 int
321 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
322 	u_int duration, u_int mindwell, u_int maxdwell,
323 	u_int nssid, const struct ieee80211_scan_ssid ssids[])
324 {
325 	const struct ieee80211_scanner *scan;
326 	struct ieee80211com *ic = vap->iv_ic;
327 
328 	scan = ieee80211_scanner_get(vap->iv_opmode);
329 	if (scan == NULL) {
330 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
331 		    "%s: no scanner support for %s mode\n",
332 		    __func__, ieee80211_opmode_name[vap->iv_opmode]);
333 		/* XXX stat */
334 		return 0;
335 	}
336 
337 	return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
338 	    mindwell, maxdwell, nssid, ssids);
339 }
340 
341 /*
342  * Check the scan cache for an ap/channel to use; if that
343  * fails then kick off a new scan.
344  */
345 int
346 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
347 	u_int duration, u_int mindwell, u_int maxdwell,
348 	u_int nssid, const struct ieee80211_scan_ssid ssids[])
349 {
350 	struct ieee80211com *ic = vap->iv_ic;
351 	struct ieee80211_scan_state *ss = ic->ic_scan;
352 	const struct ieee80211_scanner *scan;
353 	int result;
354 
355 	scan = ieee80211_scanner_get(vap->iv_opmode);
356 	if (scan == NULL) {
357 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
358 		    "%s: no scanner support for %s mode\n",
359 		    __func__, vap->iv_opmode);
360 		/* XXX stat */
361 		return 0;
362 	}
363 
364 	/*
365 	 * Check if there's a list of scan candidates already.
366 	 * XXX want more than the ap we're currently associated with
367 	 */
368 
369 	IEEE80211_LOCK(ic);
370 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
371 	    "%s: %s scan, %s%s%s%s%s\n"
372 	    , __func__
373 	    , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
374 	    , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
375 	    , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
376 	    , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
377 	    , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
378 	    , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
379 	);
380 
381 	if (ss->ss_ops != scan) {
382 		/* XXX re-use cache contents? e.g. adhoc<->sta */
383 		flags |= IEEE80211_SCAN_FLUSH;
384 	}
385 
386 	/*
387 	 * XXX TODO: separate things out a bit better.
388 	 */
389 	ieee80211_scan_update_locked(vap, scan);
390 
391 	result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
392 	    mindwell, maxdwell, nssid, ssids);
393 
394 	IEEE80211_UNLOCK(ic);
395 
396 	return (result);
397 }
398 
399 /*
400  * Check the scan cache for an ap/channel to use; if that fails
401  * then kick off a scan using the current settings.
402  */
403 int
404 ieee80211_check_scan_current(struct ieee80211vap *vap)
405 {
406 	return ieee80211_check_scan(vap,
407 	    IEEE80211_SCAN_ACTIVE,
408 	    IEEE80211_SCAN_FOREVER, 0, 0,
409 	    vap->iv_des_nssid, vap->iv_des_ssid);
410 }
411 
412 /*
413  * Restart a previous scan.  If the previous scan completed
414  * then we start again using the existing channel list.
415  */
416 int
417 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
418 {
419 	struct ieee80211com *ic = vap->iv_ic;
420 	const struct ieee80211_scanner *scan;
421 
422 	// IEEE80211_UNLOCK_ASSERT(sc);
423 
424 	scan = ieee80211_scanner_get(vap->iv_opmode);
425 	if (scan == NULL) {
426 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
427 		    "%s: no scanner support for %s mode\n",
428 		    __func__, vap->iv_opmode);
429 		/* XXX stat */
430 		return 0;
431 	}
432 
433 	/*
434 	 * XXX TODO: pull apart the bgscan logic into whatever
435 	 * belongs here and whatever belongs in the software
436 	 * scanner.
437 	 */
438 	return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
439 }
440 
441 /*
442  * Cancel any scan currently going on for the specified vap.
443  */
444 void
445 ieee80211_cancel_scan(struct ieee80211vap *vap)
446 {
447 	struct ieee80211com *ic = vap->iv_ic;
448 
449 	ic->ic_scan_methods->sc_cancel_scan(vap);
450 }
451 
452 /*
453  * Cancel any scan currently going on.
454  *
455  * This is called during normal 802.11 data path to cancel
456  * a scan so a newly arrived normal data packet can be sent.
457  */
458 void
459 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
460 {
461 	struct ieee80211com *ic = vap->iv_ic;
462 
463 	ic->ic_scan_methods->sc_cancel_anyscan(vap);
464 }
465 
466 /*
467  * Manually switch to the next channel in the channel list.
468  * Provided for drivers that manage scanning themselves
469  * (e.g. for firmware-based devices).
470  */
471 void
472 ieee80211_scan_next(struct ieee80211vap *vap)
473 {
474 	struct ieee80211com *ic = vap->iv_ic;
475 
476 	ic->ic_scan_methods->sc_scan_next(vap);
477 }
478 
479 /*
480  * Manually stop a scan that is currently running.
481  * Provided for drivers that are not able to scan single channels
482  * (e.g. for firmware-based devices).
483  */
484 void
485 ieee80211_scan_done(struct ieee80211vap *vap)
486 {
487 	struct ieee80211com *ic = vap->iv_ic;
488 	struct ieee80211_scan_state *ss;
489 
490 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
491 
492 	IEEE80211_LOCK(ic);
493 	ss = ic->ic_scan;
494 	ss->ss_next = ss->ss_last; /* all channels are complete */
495 
496 	ic->ic_scan_methods->sc_scan_done(vap);
497 
498 	IEEE80211_UNLOCK(ic);
499 }
500 
501 /*
502  * Probe the current channel, if allowed, while scanning.
503  * If the channel is not marked passive-only then send
504  * a probe request immediately.  Otherwise mark state and
505  * listen for beacons on the channel; if we receive something
506  * then we'll transmit a probe request.
507  */
508 void
509 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
510 {
511 	struct ieee80211com *ic = vap->iv_ic;
512 
513 	if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
514 		ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
515 		return;
516 	}
517 
518 	ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
519 }
520 
521 #ifdef IEEE80211_DEBUG
522 static void
523 dump_country(const uint8_t *ie)
524 {
525 	const struct ieee80211_country_ie *cie =
526 	   (const struct ieee80211_country_ie *) ie;
527 	int i, nbands, schan, nchan;
528 
529 	if (cie->len < 3) {
530 		printf(" <bogus country ie, len %d>", cie->len);
531 		return;
532 	}
533 	printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
534 	nbands = (cie->len - 3) / sizeof(cie->band[0]);
535 	for (i = 0; i < nbands; i++) {
536 		schan = cie->band[i].schan;
537 		nchan = cie->band[i].nchan;
538 		if (nchan != 1)
539 			printf(" %u-%u,%u", schan, schan + nchan-1,
540 			    cie->band[i].maxtxpwr);
541 		else
542 			printf(" %u,%u", schan, cie->band[i].maxtxpwr);
543 	}
544 	printf("]");
545 }
546 
547 void
548 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
549 	const uint8_t mac[IEEE80211_ADDR_LEN],
550 	const struct ieee80211_scanparams *sp, int rssi)
551 {
552 
553 	printf("[%s] %s%s on chan %u (bss chan %u) ",
554 	    ether_sprintf(mac), isnew ? "new " : "",
555 	    ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
556 	ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
557 	printf(" rssi %d\n", rssi);
558 
559 	if (isnew) {
560 		printf("[%s] caps 0x%x bintval %u erp 0x%x",
561 			ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
562 		if (sp->country != NULL)
563 			dump_country(sp->country);
564 		printf("\n");
565 	}
566 }
567 #endif /* IEEE80211_DEBUG */
568 
569 /*
570  * Process a beacon or probe response frame.
571  */
572 void
573 ieee80211_add_scan(struct ieee80211vap *vap,
574 	struct ieee80211_channel *curchan,
575 	const struct ieee80211_scanparams *sp,
576 	const struct ieee80211_frame *wh,
577 	int subtype, int rssi, int noise)
578 {
579 	struct ieee80211com *ic = vap->iv_ic;
580 
581 	return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
582 	    rssi, noise));
583 }
584 
585 /*
586  * Timeout/age scan cache entries; called from sta timeout
587  * timer (XXX should be self-contained).
588  */
589 void
590 ieee80211_scan_timeout(struct ieee80211com *ic)
591 {
592 	struct ieee80211_scan_state *ss = ic->ic_scan;
593 
594 	if (ss->ss_ops != NULL)
595 		ss->ss_ops->scan_age(ss);
596 }
597 
598 /*
599  * Mark a scan cache entry after a successful associate.
600  */
601 void
602 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
603 {
604 	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
605 
606 	if (ss->ss_ops != NULL) {
607 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
608 			mac, "%s",  __func__);
609 		ss->ss_ops->scan_assoc_success(ss, mac);
610 	}
611 }
612 
613 /*
614  * Demerit a scan cache entry after failing to associate.
615  */
616 void
617 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
618 	const uint8_t mac[], int reason)
619 {
620 	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
621 
622 	if (ss->ss_ops != NULL) {
623 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
624 			"%s: reason %u", __func__, reason);
625 		ss->ss_ops->scan_assoc_fail(ss, mac, reason);
626 	}
627 }
628 
629 /*
630  * Iterate over the contents of the scan cache.
631  */
632 void
633 ieee80211_scan_iterate(struct ieee80211vap *vap,
634 	ieee80211_scan_iter_func *f, void *arg)
635 {
636 	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
637 
638 	if (ss->ss_ops != NULL)
639 		ss->ss_ops->scan_iterate(ss, f, arg);
640 }
641 
642 /*
643  * Flush the contents of the scan cache.
644  */
645 void
646 ieee80211_scan_flush(struct ieee80211vap *vap)
647 {
648 	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
649 
650 	if (ss->ss_ops != NULL && ss->ss_vap == vap) {
651 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n",  __func__);
652 		ss->ss_ops->scan_flush(ss);
653 	}
654 }
655 
656 /*
657  * Check the scan cache for an ap/channel to use; if that
658  * fails then kick off a new scan.
659  */
660 struct ieee80211_channel *
661 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
662 {
663 	struct ieee80211_scan_state *ss = ic->ic_scan;
664 
665 	IEEE80211_LOCK_ASSERT(ic);
666 
667 	if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
668 		/* XXX printf? */
669 		return NULL;
670 	}
671 	if (ss->ss_ops->scan_pickchan == NULL) {
672 		IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
673 		    "%s: scan module does not support picking a channel, "
674 		    "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
675 		return NULL;
676 	}
677 	return ss->ss_ops->scan_pickchan(ss, flags);
678 }
679