1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
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/*
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/malloc.h>
39#include <sys/condvar.h>
40
41#include <sys/socket.h>
42
43#include <net/if.h>
44#include <net/if_var.h>
45#include <net/if_media.h>
46#include <net/if_private.h>
47#include <net/ethernet.h>
48
49#include <net80211/ieee80211_var.h>
50
51/* XXX until it's implemented as attach ops */
52#include <net80211/ieee80211_scan_sw.h>
53
54#include <net/bpf.h>
55
56/*
57 * Roaming-related defaults.  RSSI thresholds are as returned by the
58 * driver (.5dBm).  Transmit rate thresholds are IEEE rate codes (i.e
59 * .5M units) or MCS.
60 */
61/* rssi thresholds */
62#define	ROAM_RSSI_11A_DEFAULT		14	/* 11a bss */
63#define	ROAM_RSSI_11B_DEFAULT		14	/* 11b bss */
64#define	ROAM_RSSI_11BONLY_DEFAULT	14	/* 11b-only bss */
65/* transmit rate thresholds */
66#define	ROAM_RATE_11A_DEFAULT		2*12	/* 11a bss */
67#define	ROAM_RATE_11B_DEFAULT		2*5	/* 11b bss */
68#define	ROAM_RATE_11BONLY_DEFAULT	2*1	/* 11b-only bss */
69#define	ROAM_RATE_HALF_DEFAULT		2*6	/* half-width 11a/g bss */
70#define	ROAM_RATE_QUARTER_DEFAULT	2*3	/* quarter-width 11a/g bss */
71#define	ROAM_MCS_11N_DEFAULT		(1 | IEEE80211_RATE_MCS) /* 11n bss */
72#define	ROAM_MCS_11AC_DEFAULT		(1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
73
74void
75ieee80211_scan_attach(struct ieee80211com *ic)
76{
77	/*
78	 * If there's no scan method pointer, attach the
79	 * swscan set as a default.
80	 */
81	if (ic->ic_scan_methods == NULL)
82		ieee80211_swscan_attach(ic);
83	else
84		ic->ic_scan_methods->sc_attach(ic);
85}
86
87void
88ieee80211_scan_detach(struct ieee80211com *ic)
89{
90
91	/*
92	 * Ideally we'd do the ss_ops detach call here;
93	 * but then sc_detach() would need to be split in two.
94	 *
95	 * I'll do that later.
96	 */
97	ic->ic_scan_methods->sc_detach(ic);
98}
99
100static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
101	[IEEE80211_MODE_11A]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
102				    .rate = ROAM_RATE_11A_DEFAULT },
103	[IEEE80211_MODE_11G]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
104				    .rate = ROAM_RATE_11B_DEFAULT },
105	[IEEE80211_MODE_11B]	= { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
106				    .rate = ROAM_RATE_11BONLY_DEFAULT },
107	[IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
108				    .rate = ROAM_RATE_11A_DEFAULT },
109	[IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
110				    .rate = ROAM_RATE_11A_DEFAULT },
111	[IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
112				    .rate = ROAM_RATE_11A_DEFAULT },
113	[IEEE80211_MODE_HALF]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
114				    .rate = ROAM_RATE_HALF_DEFAULT },
115	[IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
116				    .rate = ROAM_RATE_QUARTER_DEFAULT },
117	[IEEE80211_MODE_11NA]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
118				    .rate = ROAM_MCS_11N_DEFAULT },
119	[IEEE80211_MODE_11NG]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
120				    .rate = ROAM_MCS_11N_DEFAULT },
121	[IEEE80211_MODE_VHT_2GHZ]	= { .rssi = ROAM_RSSI_11B_DEFAULT,
122				    .rate = ROAM_MCS_11AC_DEFAULT },
123	[IEEE80211_MODE_VHT_5GHZ]	= { .rssi = ROAM_RSSI_11A_DEFAULT,
124				    .rate = ROAM_MCS_11AC_DEFAULT },
125
126};
127
128void
129ieee80211_scan_vattach(struct ieee80211vap *vap)
130{
131	struct ieee80211com *ic = vap->iv_ic;
132	int m;
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
140	memset(vap->iv_roamparms, 0, sizeof(vap->iv_roamparms));
141	for (m = IEEE80211_MODE_AUTO + 1; m < IEEE80211_MODE_MAX; m++) {
142		if (isclr(ic->ic_modecaps, m))
143			continue;
144
145		memcpy(&vap->iv_roamparms[m], &defroam[m], sizeof(defroam[m]));
146	}
147
148	ic->ic_scan_methods->sc_vattach(vap);
149}
150
151void
152ieee80211_scan_vdetach(struct ieee80211vap *vap)
153{
154	struct ieee80211com *ic = vap->iv_ic;
155	struct ieee80211_scan_state *ss;
156
157	IEEE80211_LOCK(ic);
158	ss = ic->ic_scan;
159
160	ic->ic_scan_methods->sc_vdetach(vap);
161
162	if (ss != NULL && ss->ss_vap == vap) {
163		if (ss->ss_ops != NULL) {
164			ss->ss_ops->scan_detach(ss);
165			ss->ss_ops = NULL;
166		}
167		ss->ss_vap = NULL;
168	}
169	IEEE80211_UNLOCK(ic);
170}
171
172/*
173 * Simple-minded scanner module support.
174 */
175static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
176	"wlan_scan_sta",	/* IEEE80211_M_IBSS */
177	"wlan_scan_sta",	/* IEEE80211_M_STA */
178	"wlan_scan_wds",	/* IEEE80211_M_WDS */
179	"wlan_scan_sta",	/* IEEE80211_M_AHDEMO */
180	"wlan_scan_ap",		/* IEEE80211_M_HOSTAP */
181	"wlan_scan_monitor",	/* IEEE80211_M_MONITOR */
182	"wlan_scan_sta",	/* IEEE80211_M_MBSS */
183};
184static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
185
186const struct ieee80211_scanner *
187ieee80211_scanner_get(enum ieee80211_opmode mode)
188{
189	if (mode >= IEEE80211_OPMODE_MAX)
190		return NULL;
191	if (scanners[mode] == NULL)
192		ieee80211_load_module(scan_modnames[mode]);
193	return scanners[mode];
194}
195
196void
197ieee80211_scanner_register(enum ieee80211_opmode mode,
198	const struct ieee80211_scanner *scan)
199{
200	if (mode >= IEEE80211_OPMODE_MAX)
201		return;
202	scanners[mode] = scan;
203}
204
205void
206ieee80211_scanner_unregister(enum ieee80211_opmode mode,
207	const struct ieee80211_scanner *scan)
208{
209	if (mode >= IEEE80211_OPMODE_MAX)
210		return;
211	if (scanners[mode] == scan)
212		scanners[mode] = NULL;
213}
214
215void
216ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
217{
218	int m;
219
220	for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
221		if (scanners[m] == scan)
222			scanners[m] = NULL;
223}
224
225/*
226 * Update common scanner state to reflect the current
227 * operating mode.  This is called when the state machine
228 * is transitioned to RUN state w/o scanning--e.g. when
229 * operating in monitor mode.  The purpose of this is to
230 * ensure later callbacks find ss_ops set to properly
231 * reflect current operating mode.
232 */
233void
234ieee80211_scan_update_locked(struct ieee80211vap *vap,
235	const struct ieee80211_scanner *scan)
236{
237	struct ieee80211com *ic = vap->iv_ic;
238	struct ieee80211_scan_state *ss = ic->ic_scan;
239
240	IEEE80211_LOCK_ASSERT(ic);
241
242#ifdef IEEE80211_DEBUG
243	if (ss->ss_vap != vap || ss->ss_ops != scan) {
244		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
245		    "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
246		    __func__,
247		    ss->ss_vap != NULL ?
248			ss->ss_vap->iv_ifp->if_xname : "none",
249		    ss->ss_vap != NULL ?
250			ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
251		    vap->iv_ifp->if_xname,
252		    ieee80211_opmode_name[vap->iv_opmode]);
253	}
254#endif
255	ss->ss_vap = vap;
256	if (ss->ss_ops != scan) {
257		/*
258		 * Switch scanners; detach old, attach new.  Special
259		 * case where a single scan module implements multiple
260		 * policies by using different scan ops but a common
261		 * core.  We assume if the old and new attach methods
262		 * are identical then it's ok to just change ss_ops
263		 * and not flush the internal state of the module.
264		 */
265		if (scan == NULL || ss->ss_ops == NULL ||
266		    ss->ss_ops->scan_attach != scan->scan_attach) {
267			if (ss->ss_ops != NULL)
268				ss->ss_ops->scan_detach(ss);
269			if (scan != NULL && !scan->scan_attach(ss)) {
270				/* XXX attach failure */
271				/* XXX stat+msg */
272				scan = NULL;
273			}
274		}
275		ss->ss_ops = scan;
276	}
277}
278
279#ifdef IEEE80211_DEBUG
280static void
281ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
282{
283	struct ieee80211com *ic = ss->ss_ic;
284	const char *sep;
285	int i;
286
287	sep = "";
288	for (i = ss->ss_next; i < ss->ss_last; i++) {
289		const struct ieee80211_channel *c = ss->ss_chans[i];
290
291		printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
292		    ieee80211_channel_type_char(c));
293		sep = ", ";
294	}
295}
296
297void
298ieee80211_scan_dump(struct ieee80211_scan_state *ss)
299{
300	struct ieee80211vap *vap = ss->ss_vap;
301
302	if_printf(vap->iv_ifp, "scan set ");
303	ieee80211_scan_dump_channels(ss);
304	printf(" dwell min %ums max %ums\n",
305	    ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
306}
307#endif /* IEEE80211_DEBUG */
308
309void
310ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
311	int nssid, const struct ieee80211_scan_ssid ssids[])
312{
313	if (nssid > IEEE80211_SCAN_MAX_SSID) {
314		/* XXX printf */
315		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
316		    "%s: too many ssid %d, ignoring all of them\n",
317		    __func__, nssid);
318		return;
319	}
320	memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
321	ss->ss_nssid = nssid;
322}
323
324/*
325 * Start a scan unless one is already going.
326 */
327int
328ieee80211_start_scan(struct ieee80211vap *vap, int flags,
329	u_int duration, u_int mindwell, u_int maxdwell,
330	u_int nssid, const struct ieee80211_scan_ssid ssids[])
331{
332	const struct ieee80211_scanner *scan;
333	struct ieee80211com *ic = vap->iv_ic;
334
335	scan = ieee80211_scanner_get(vap->iv_opmode);
336	if (scan == NULL) {
337		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
338		    "%s: no scanner support for %s mode\n",
339		    __func__, ieee80211_opmode_name[vap->iv_opmode]);
340		/* XXX stat */
341		return 0;
342	}
343
344	return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
345	    mindwell, maxdwell, nssid, ssids);
346}
347
348/*
349 * Check the scan cache for an ap/channel to use; if that
350 * fails then kick off a new scan.
351 */
352int
353ieee80211_check_scan(struct ieee80211vap *vap, int flags,
354	u_int duration, u_int mindwell, u_int maxdwell,
355	u_int nssid, const struct ieee80211_scan_ssid ssids[])
356{
357	struct ieee80211com *ic = vap->iv_ic;
358	struct ieee80211_scan_state *ss = ic->ic_scan;
359	const struct ieee80211_scanner *scan;
360	int result;
361
362	scan = ieee80211_scanner_get(vap->iv_opmode);
363	if (scan == NULL) {
364		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
365		    "%s: no scanner support for %s mode\n",
366		    __func__, vap->iv_opmode);
367		/* XXX stat */
368		return 0;
369	}
370
371	/*
372	 * Check if there's a list of scan candidates already.
373	 * XXX want more than the ap we're currently associated with
374	 */
375
376	IEEE80211_LOCK(ic);
377	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
378	    "%s: %s scan, %s%s%s%s%s\n"
379	    , __func__
380	    , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
381	    , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
382	    , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
383	    , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
384	    , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
385	    , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
386	);
387
388	if (ss->ss_ops != scan) {
389		/* XXX re-use cache contents? e.g. adhoc<->sta */
390		flags |= IEEE80211_SCAN_FLUSH;
391	}
392
393	/*
394	 * XXX TODO: separate things out a bit better.
395	 */
396	ieee80211_scan_update_locked(vap, scan);
397
398	result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
399	    mindwell, maxdwell, nssid, ssids);
400
401	IEEE80211_UNLOCK(ic);
402
403	return (result);
404}
405
406/*
407 * Check the scan cache for an ap/channel to use; if that fails
408 * then kick off a scan using the current settings.
409 */
410int
411ieee80211_check_scan_current(struct ieee80211vap *vap)
412{
413	return ieee80211_check_scan(vap,
414	    IEEE80211_SCAN_ACTIVE,
415	    IEEE80211_SCAN_FOREVER, 0, 0,
416	    vap->iv_des_nssid, vap->iv_des_ssid);
417}
418
419/*
420 * Restart a previous scan.  If the previous scan completed
421 * then we start again using the existing channel list.
422 */
423int
424ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
425{
426	struct ieee80211com *ic = vap->iv_ic;
427	const struct ieee80211_scanner *scan;
428
429	// IEEE80211_UNLOCK_ASSERT(sc);
430
431	scan = ieee80211_scanner_get(vap->iv_opmode);
432	if (scan == NULL) {
433		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
434		    "%s: no scanner support for %s mode\n",
435		    __func__, vap->iv_opmode);
436		/* XXX stat */
437		return 0;
438	}
439
440	/*
441	 * XXX TODO: pull apart the bgscan logic into whatever
442	 * belongs here and whatever belongs in the software
443	 * scanner.
444	 */
445	return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
446}
447
448/*
449 * Cancel any scan currently going on for the specified vap.
450 */
451void
452ieee80211_cancel_scan(struct ieee80211vap *vap)
453{
454	struct ieee80211com *ic = vap->iv_ic;
455
456	ic->ic_scan_methods->sc_cancel_scan(vap);
457}
458
459/*
460 * Cancel any scan currently going on.
461 *
462 * This is called during normal 802.11 data path to cancel
463 * a scan so a newly arrived normal data packet can be sent.
464 */
465void
466ieee80211_cancel_anyscan(struct ieee80211vap *vap)
467{
468	struct ieee80211com *ic = vap->iv_ic;
469
470	ic->ic_scan_methods->sc_cancel_anyscan(vap);
471}
472
473/*
474 * Manually switch to the next channel in the channel list.
475 * Provided for drivers that manage scanning themselves
476 * (e.g. for firmware-based devices).
477 */
478void
479ieee80211_scan_next(struct ieee80211vap *vap)
480{
481	struct ieee80211com *ic = vap->iv_ic;
482
483	ic->ic_scan_methods->sc_scan_next(vap);
484}
485
486/*
487 * Manually stop a scan that is currently running.
488 * Provided for drivers that are not able to scan single channels
489 * (e.g. for firmware-based devices).
490 */
491void
492ieee80211_scan_done(struct ieee80211vap *vap)
493{
494	struct ieee80211com *ic = vap->iv_ic;
495	struct ieee80211_scan_state *ss;
496
497	IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
498
499	IEEE80211_LOCK(ic);
500	ss = ic->ic_scan;
501	ss->ss_next = ss->ss_last; /* all channels are complete */
502
503	ic->ic_scan_methods->sc_scan_done(vap);
504
505	IEEE80211_UNLOCK(ic);
506}
507
508/*
509 * Probe the current channel, if allowed, while scanning.
510 * If the channel is not marked passive-only then send
511 * a probe request immediately.  Otherwise mark state and
512 * listen for beacons on the channel; if we receive something
513 * then we'll transmit a probe request.
514 */
515void
516ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
517{
518	struct ieee80211com *ic = vap->iv_ic;
519
520	if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
521		ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
522		return;
523	}
524
525	ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
526}
527
528#ifdef IEEE80211_DEBUG
529static void
530dump_country(const uint8_t *ie)
531{
532	const struct ieee80211_country_ie *cie =
533	   (const struct ieee80211_country_ie *) ie;
534	int i, nbands, schan, nchan;
535
536	if (cie->len < 3) {
537		printf(" <bogus country ie, len %d>", cie->len);
538		return;
539	}
540	printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
541	nbands = (cie->len - 3) / sizeof(cie->band[0]);
542	for (i = 0; i < nbands; i++) {
543		schan = cie->band[i].schan;
544		nchan = cie->band[i].nchan;
545		if (nchan != 1)
546			printf(" %u-%u,%u", schan, schan + nchan-1,
547			    cie->band[i].maxtxpwr);
548		else
549			printf(" %u,%u", schan, cie->band[i].maxtxpwr);
550	}
551	printf("]");
552}
553
554void
555ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
556	const uint8_t mac[IEEE80211_ADDR_LEN],
557	const struct ieee80211_scanparams *sp, int rssi)
558{
559
560	printf("[%s] %s%s on chan %u (bss chan %u) ",
561	    ether_sprintf(mac), isnew ? "new " : "",
562	    ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
563	ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
564	printf(" rssi %d\n", rssi);
565
566	if (isnew) {
567		printf("[%s] caps 0x%x bintval %u erp 0x%x",
568			ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
569		if (sp->country != NULL)
570			dump_country(sp->country);
571		printf("\n");
572	}
573}
574#endif /* IEEE80211_DEBUG */
575
576/*
577 * Process a beacon or probe response frame.
578 */
579void
580ieee80211_add_scan(struct ieee80211vap *vap,
581	struct ieee80211_channel *curchan,
582	const struct ieee80211_scanparams *sp,
583	const struct ieee80211_frame *wh,
584	int subtype, int rssi, int noise)
585{
586	struct ieee80211com *ic = vap->iv_ic;
587
588	return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
589	    rssi, noise));
590}
591
592/*
593 * Timeout/age scan cache entries; called from sta timeout
594 * timer (XXX should be self-contained).
595 */
596void
597ieee80211_scan_timeout(struct ieee80211com *ic)
598{
599	struct ieee80211_scan_state *ss = ic->ic_scan;
600
601	if (ss->ss_ops != NULL)
602		ss->ss_ops->scan_age(ss);
603}
604
605/*
606 * Mark a scan cache entry after a successful associate.
607 */
608void
609ieee80211_scan_assoc_success(struct ieee80211vap *vap,
610    const uint8_t mac[IEEE80211_ADDR_LEN])
611{
612	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
613
614	if (ss->ss_ops != NULL) {
615		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
616			mac, "%s",  __func__);
617		ss->ss_ops->scan_assoc_success(ss, mac);
618	}
619}
620
621/*
622 * Demerit a scan cache entry after failing to associate.
623 */
624void
625ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
626	const uint8_t mac[IEEE80211_ADDR_LEN], int reason)
627{
628	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
629
630	if (ss->ss_ops != NULL) {
631		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
632			"%s: reason %u", __func__, reason);
633		ss->ss_ops->scan_assoc_fail(ss, mac, reason);
634	}
635}
636
637/*
638 * Iterate over the contents of the scan cache.
639 */
640void
641ieee80211_scan_iterate(struct ieee80211vap *vap,
642	ieee80211_scan_iter_func *f, void *arg)
643{
644	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
645
646	if (ss->ss_ops != NULL)
647		ss->ss_ops->scan_iterate(ss, f, arg);
648}
649
650/*
651 * Flush the contents of the scan cache.
652 */
653void
654ieee80211_scan_flush(struct ieee80211vap *vap)
655{
656	struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
657
658	if (ss->ss_ops != NULL && ss->ss_vap == vap) {
659		IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n",  __func__);
660		ss->ss_ops->scan_flush(ss);
661	}
662}
663
664/*
665 * Check the scan cache for an ap/channel to use; if that
666 * fails then kick off a new scan.
667 */
668struct ieee80211_channel *
669ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
670{
671	struct ieee80211_scan_state *ss = ic->ic_scan;
672
673	IEEE80211_LOCK_ASSERT(ic);
674
675	if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
676		/* XXX printf? */
677		return NULL;
678	}
679	if (ss->ss_ops->scan_pickchan == NULL) {
680		IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
681		    "%s: scan module does not support picking a channel, "
682		    "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
683		return NULL;
684	}
685	return ss->ss_ops->scan_pickchan(ss, flags);
686}
687