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ieee80211_scan_sw.c (184205) ieee80211_scan_sw.c (184210)
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>
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: head/sys/net80211/ieee80211_scan.c 184205 2008-10-23 15:53:51Z des $");
27__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_scan.c 184210 2008-10-23 19:57:13Z des $");
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/kernel.h>
37
38#include <sys/socket.h>
39
40#include <net/if.h>
41#include <net/if_media.h>
42#include <net/ethernet.h>
43
44#include <net80211/ieee80211_var.h>
45
46#include <net/bpf.h>
47
48struct scan_state {
49 struct ieee80211_scan_state base; /* public state */
50
51 u_int ss_iflags; /* flags used internally */
52#define ISCAN_MINDWELL 0x0001 /* min dwell time reached */
53#define ISCAN_DISCARD 0x0002 /* discard rx'd frames */
54#define ISCAN_CANCEL 0x0004 /* cancel current scan */
55#define ISCAN_START 0x0008 /* 1st time through next_scan */
56 unsigned long ss_chanmindwell; /* min dwell on curchan */
57 unsigned long ss_scanend; /* time scan must stop */
58 u_int ss_duration; /* duration for next scan */
59 struct callout ss_scan_timer; /* scan timer */
60};
61#define SCAN_PRIVATE(ss) ((struct scan_state *) ss)
62
63/*
64 * Amount of time to go off-channel during a background
65 * scan. This value should be large enough to catch most
66 * ap's but short enough that we can return on-channel
67 * before our listen interval expires.
68 *
69 * XXX tunable
70 * XXX check against configured listen interval
71 */
72#define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150)
73
74/*
75 * Roaming-related defaults. RSSI thresholds are as returned by the
76 * driver (dBm). Transmit rate thresholds are IEEE rate codes (i.e
77 * .5M units) or MCS.
78 */
79#define ROAM_RSSI_11A_DEFAULT 14 /* rssi threshold for 11a bss */
80#define ROAM_RSSI_11B_DEFAULT 14 /* rssi threshold for 11b bss */
81#define ROAM_RSSI_11BONLY_DEFAULT 14 /* rssi threshold for 11b-only bss */
82#define ROAM_RATE_11A_DEFAULT 2*12 /* tx rate thresh for 11a bss */
83#define ROAM_RATE_11B_DEFAULT 2*5 /* tx rate thresh for 11b bss */
84#define ROAM_RATE_11BONLY_DEFAULT 2*1 /* tx rate thresh for 11b-only bss */
85#define ROAM_MCS_11N_DEFAULT 1 /* tx MCS thresh for 11n bss*/
86
87static void scan_restart_pwrsav(void *);
88static void scan_curchan(struct ieee80211_scan_state *, unsigned long);
89static void scan_mindwell(struct ieee80211_scan_state *);
90static void scan_next(void *);
91
92MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state");
93
94void
95ieee80211_scan_attach(struct ieee80211com *ic)
96{
97 struct scan_state *ss;
98
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/kernel.h>
37
38#include <sys/socket.h>
39
40#include <net/if.h>
41#include <net/if_media.h>
42#include <net/ethernet.h>
43
44#include <net80211/ieee80211_var.h>
45
46#include <net/bpf.h>
47
48struct scan_state {
49 struct ieee80211_scan_state base; /* public state */
50
51 u_int ss_iflags; /* flags used internally */
52#define ISCAN_MINDWELL 0x0001 /* min dwell time reached */
53#define ISCAN_DISCARD 0x0002 /* discard rx'd frames */
54#define ISCAN_CANCEL 0x0004 /* cancel current scan */
55#define ISCAN_START 0x0008 /* 1st time through next_scan */
56 unsigned long ss_chanmindwell; /* min dwell on curchan */
57 unsigned long ss_scanend; /* time scan must stop */
58 u_int ss_duration; /* duration for next scan */
59 struct callout ss_scan_timer; /* scan timer */
60};
61#define SCAN_PRIVATE(ss) ((struct scan_state *) ss)
62
63/*
64 * Amount of time to go off-channel during a background
65 * scan. This value should be large enough to catch most
66 * ap's but short enough that we can return on-channel
67 * before our listen interval expires.
68 *
69 * XXX tunable
70 * XXX check against configured listen interval
71 */
72#define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150)
73
74/*
75 * Roaming-related defaults. RSSI thresholds are as returned by the
76 * driver (dBm). Transmit rate thresholds are IEEE rate codes (i.e
77 * .5M units) or MCS.
78 */
79#define ROAM_RSSI_11A_DEFAULT 14 /* rssi threshold for 11a bss */
80#define ROAM_RSSI_11B_DEFAULT 14 /* rssi threshold for 11b bss */
81#define ROAM_RSSI_11BONLY_DEFAULT 14 /* rssi threshold for 11b-only bss */
82#define ROAM_RATE_11A_DEFAULT 2*12 /* tx rate thresh for 11a bss */
83#define ROAM_RATE_11B_DEFAULT 2*5 /* tx rate thresh for 11b bss */
84#define ROAM_RATE_11BONLY_DEFAULT 2*1 /* tx rate thresh for 11b-only bss */
85#define ROAM_MCS_11N_DEFAULT 1 /* tx MCS thresh for 11n bss*/
86
87static void scan_restart_pwrsav(void *);
88static void scan_curchan(struct ieee80211_scan_state *, unsigned long);
89static void scan_mindwell(struct ieee80211_scan_state *);
90static void scan_next(void *);
91
92MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state");
93
94void
95ieee80211_scan_attach(struct ieee80211com *ic)
96{
97 struct scan_state *ss;
98
99 ss = malloc(sizeof(struct scan_state),
99 MALLOC(ss, struct scan_state *, sizeof(struct scan_state),
100 M_80211_SCAN, M_NOWAIT | M_ZERO);
101 if (ss == NULL) {
102 ic->ic_scan = NULL;
103 return;
104 }
105 callout_init_mtx(&ss->ss_scan_timer, IEEE80211_LOCK_OBJ(ic), 0);
106 ic->ic_scan = &ss->base;
107
108 ic->ic_scan_curchan = scan_curchan;
109 ic->ic_scan_mindwell = scan_mindwell;
110}
111
112void
113ieee80211_scan_detach(struct ieee80211com *ic)
114{
115 struct ieee80211_scan_state *ss = ic->ic_scan;
116
117 if (ss != NULL) {
118 callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer);
119 if (ss->ss_ops != NULL) {
120 ss->ss_ops->scan_detach(ss);
121 ss->ss_ops = NULL;
122 }
123 ic->ic_flags &= ~IEEE80211_F_SCAN;
124 ic->ic_scan = NULL;
100 M_80211_SCAN, M_NOWAIT | M_ZERO);
101 if (ss == NULL) {
102 ic->ic_scan = NULL;
103 return;
104 }
105 callout_init_mtx(&ss->ss_scan_timer, IEEE80211_LOCK_OBJ(ic), 0);
106 ic->ic_scan = &ss->base;
107
108 ic->ic_scan_curchan = scan_curchan;
109 ic->ic_scan_mindwell = scan_mindwell;
110}
111
112void
113ieee80211_scan_detach(struct ieee80211com *ic)
114{
115 struct ieee80211_scan_state *ss = ic->ic_scan;
116
117 if (ss != NULL) {
118 callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer);
119 if (ss->ss_ops != NULL) {
120 ss->ss_ops->scan_detach(ss);
121 ss->ss_ops = NULL;
122 }
123 ic->ic_flags &= ~IEEE80211_F_SCAN;
124 ic->ic_scan = NULL;
125 free(SCAN_PRIVATE(ss), M_80211_SCAN);
125 FREE(SCAN_PRIVATE(ss), M_80211_SCAN);
126 }
127}
128
129static __inline void
130setparams(struct ieee80211_roamparam *rp, int8_t rssi, uint8_t txrate)
131{
132 rp->rssi = rssi;
133 rp->rate = txrate;
134}
135
136void
137ieee80211_scan_vattach(struct ieee80211vap *vap)
138{
139 struct ieee80211com *ic = vap->iv_ic;
140
141 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
142 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
143 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
144
145 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
146
147 /* NB: only set supported modes so user apps can identify */
148 if (isset(ic->ic_modecaps, IEEE80211_MODE_11A))
149 setparams(&vap->iv_roamparms[IEEE80211_MODE_11A],
150 ROAM_RSSI_11A_DEFAULT, ROAM_RATE_11A_DEFAULT);
151 if (isset(ic->ic_modecaps, IEEE80211_MODE_11G))
152 setparams(&vap->iv_roamparms[IEEE80211_MODE_11G],
153 ROAM_RSSI_11B_DEFAULT, ROAM_RATE_11B_DEFAULT);
154 if (isset(ic->ic_modecaps, IEEE80211_MODE_11B))
155 setparams(&vap->iv_roamparms[IEEE80211_MODE_11B],
156 ROAM_RSSI_11BONLY_DEFAULT, ROAM_RATE_11BONLY_DEFAULT);
157 /* NB: default turbo controls to be the same as !turbo */
158 if (isset(ic->ic_modecaps, IEEE80211_MODE_TURBO_A))
159 vap->iv_roamparms[IEEE80211_MODE_TURBO_A] =
160 vap->iv_roamparms[IEEE80211_MODE_11A];
161 if (isset(ic->ic_modecaps, IEEE80211_MODE_TURBO_G))
162 vap->iv_roamparms[IEEE80211_MODE_TURBO_G] =
163 vap->iv_roamparms[IEEE80211_MODE_11G];
164 if (isset(ic->ic_modecaps, IEEE80211_MODE_STURBO_A))
165 vap->iv_roamparms[IEEE80211_MODE_STURBO_A] =
166 vap->iv_roamparms[IEEE80211_MODE_11A];
167 if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
168 setparams(&vap->iv_roamparms[IEEE80211_MODE_11NA],
169 ROAM_RSSI_11A_DEFAULT, ROAM_MCS_11N_DEFAULT | 0x80);
170 if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
171 setparams(&vap->iv_roamparms[IEEE80211_MODE_11NG],
172 ROAM_RSSI_11B_DEFAULT, ROAM_MCS_11N_DEFAULT | 0x80);
173}
174
175void
176ieee80211_scan_vdetach(struct ieee80211vap *vap)
177{
178 struct ieee80211com *ic = vap->iv_ic;
179 struct ieee80211_scan_state *ss;
180
181 IEEE80211_LOCK(ic);
182 ss = ic->ic_scan;
183 if (ss != NULL && ss->ss_vap == vap) {
184 if (ic->ic_flags & IEEE80211_F_SCAN) {
185 /* XXX callout_drain */
186 callout_stop(&SCAN_PRIVATE(ss)->ss_scan_timer);
187 ic->ic_flags &= ~IEEE80211_F_SCAN;
188 }
189 if (ss->ss_ops != NULL) {
190 ss->ss_ops->scan_detach(ss);
191 ss->ss_ops = NULL;
192 }
193 ss->ss_vap = NULL;
194 }
195 IEEE80211_UNLOCK(ic);
196}
197
198/*
199 * Simple-minded scanner module support.
200 */
201static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
202 "wlan_scan_sta", /* IEEE80211_M_IBSS */
203 "wlan_scan_sta", /* IEEE80211_M_STA */
204 "wlan_scan_wds", /* IEEE80211_M_WDS */
205 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
206 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
207 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
208};
209static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
210
211const struct ieee80211_scanner *
212ieee80211_scanner_get(enum ieee80211_opmode mode)
213{
214 if (mode >= IEEE80211_OPMODE_MAX)
215 return NULL;
216 if (scanners[mode] == NULL)
217 ieee80211_load_module(scan_modnames[mode]);
218 return scanners[mode];
219}
220
221void
222ieee80211_scanner_register(enum ieee80211_opmode mode,
223 const struct ieee80211_scanner *scan)
224{
225 if (mode >= IEEE80211_OPMODE_MAX)
226 return;
227 scanners[mode] = scan;
228}
229
230void
231ieee80211_scanner_unregister(enum ieee80211_opmode mode,
232 const struct ieee80211_scanner *scan)
233{
234 if (mode >= IEEE80211_OPMODE_MAX)
235 return;
236 if (scanners[mode] == scan)
237 scanners[mode] = NULL;
238}
239
240void
241ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
242{
243 int m;
244
245 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
246 if (scanners[m] == scan)
247 scanners[m] = NULL;
248}
249
250/*
251 * Update common scanner state to reflect the current
252 * operating mode. This is called when the state machine
253 * is transitioned to RUN state w/o scanning--e.g. when
254 * operating in monitor mode. The purpose of this is to
255 * ensure later callbacks find ss_ops set to properly
256 * reflect current operating mode.
257 */
258static void
259scan_update_locked(struct ieee80211vap *vap,
260 const struct ieee80211_scanner *scan)
261{
262 struct ieee80211com *ic = vap->iv_ic;
263 struct ieee80211_scan_state *ss = ic->ic_scan;
264
265 IEEE80211_LOCK_ASSERT(ic);
266
267#ifdef IEEE80211_DEBUG
268 if (ss->ss_vap != vap || ss->ss_ops != scan) {
269 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
270 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
271 __func__,
272 ss->ss_vap != NULL ?
273 ss->ss_vap->iv_ifp->if_xname : "none",
274 ss->ss_vap != NULL ?
275 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
276 vap->iv_ifp->if_xname,
277 ieee80211_opmode_name[vap->iv_opmode]);
278 }
279#endif
280 ss->ss_vap = vap;
281 if (ss->ss_ops != scan) {
282 /*
283 * Switch scanners; detach old, attach new. Special
284 * case where a single scan module implements multiple
285 * policies by using different scan ops but a common
286 * core. We assume if the old and new attach methods
287 * are identical then it's ok to just change ss_ops
288 * and not flush the internal state of the module.
289 */
290 if (scan == NULL || ss->ss_ops == NULL ||
291 ss->ss_ops->scan_attach != scan->scan_attach) {
292 if (ss->ss_ops != NULL)
293 ss->ss_ops->scan_detach(ss);
294 if (scan != NULL && !scan->scan_attach(ss)) {
295 /* XXX attach failure */
296 /* XXX stat+msg */
297 scan = NULL;
298 }
299 }
300 ss->ss_ops = scan;
301 }
302}
303
304static void
305change_channel(struct ieee80211com *ic,
306 struct ieee80211_channel *chan)
307{
308 ic->ic_curchan = chan;
309 ic->ic_set_channel(ic);
310}
311
312static char
313channel_type(const struct ieee80211_channel *c)
314{
315 if (IEEE80211_IS_CHAN_ST(c))
316 return 'S';
317 if (IEEE80211_IS_CHAN_108A(c))
318 return 'T';
319 if (IEEE80211_IS_CHAN_108G(c))
320 return 'G';
321 if (IEEE80211_IS_CHAN_HT(c))
322 return 'n';
323 if (IEEE80211_IS_CHAN_A(c))
324 return 'a';
325 if (IEEE80211_IS_CHAN_ANYG(c))
326 return 'g';
327 if (IEEE80211_IS_CHAN_B(c))
328 return 'b';
329 return 'f';
330}
331
332void
333ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
334{
335 struct ieee80211com *ic = ss->ss_vap->iv_ic;
336 const char *sep;
337 int i;
338
339 sep = "";
340 for (i = ss->ss_next; i < ss->ss_last; i++) {
341 const struct ieee80211_channel *c = ss->ss_chans[i];
342
343 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
344 channel_type(c));
345 sep = ", ";
346 }
347}
348
349#ifdef IEEE80211_DEBUG
350static void
351scan_dump(struct ieee80211_scan_state *ss)
352{
353 struct ieee80211vap *vap = ss->ss_vap;
354
355 if_printf(vap->iv_ifp, "scan set ");
356 ieee80211_scan_dump_channels(ss);
357 printf(" dwell min %lu max %lu\n", ss->ss_mindwell, ss->ss_maxdwell);
358}
359#endif /* IEEE80211_DEBUG */
360
361/*
362 * Enable station power save mode and start/restart the scanning thread.
363 */
364static void
365scan_restart_pwrsav(void *arg)
366{
367 struct scan_state *ss = (struct scan_state *) arg;
368 struct ieee80211vap *vap = ss->base.ss_vap;
369 struct ieee80211com *ic = vap->iv_ic;
370 int ticksdelay;
371
372 ieee80211_sta_pwrsave(vap, 1);
373 /*
374 * Use an initial 1ms delay so the null
375 * data frame has a chance to go out.
376 * XXX 1ms is a lot, better to trigger scan
377 * on tx complete.
378 */
379 ticksdelay = msecs_to_ticks(1);
380 if (ticksdelay < 1)
381 ticksdelay = 1;
382 ic->ic_scan_start(ic); /* notify driver */
383 ss->ss_scanend = ticks + ticksdelay + ss->ss_duration;
384 ss->ss_iflags |= ISCAN_START;
385 callout_reset(&ss->ss_scan_timer, ticksdelay, scan_next, ss);
386}
387
388/*
389 * Start/restart scanning. If we're operating in station mode
390 * and associated notify the ap we're going into power save mode
391 * and schedule a callback to initiate the work (where there's a
392 * better context for doing the work). Otherwise, start the scan
393 * directly.
394 */
395static int
396scan_restart(struct scan_state *ss, u_int duration)
397{
398 struct ieee80211vap *vap = ss->base.ss_vap;
399 struct ieee80211com *ic = vap->iv_ic;
400 int defer = 0;
401
402 if (ss->base.ss_next == ss->base.ss_last) {
403 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
404 "%s: no channels to scan\n", __func__);
405 return 0;
406 }
407 if (vap->iv_opmode == IEEE80211_M_STA &&
408 vap->iv_state == IEEE80211_S_RUN) {
409 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
410 /*
411 * Initiate power save before going off-channel.
412 * Note that we cannot do this directly because
413 * of locking issues; instead we defer it to a
414 * tasklet.
415 */
416 ss->ss_duration = duration;
417 defer = 1;
418 }
419 }
420
421 if (!defer) {
422 ic->ic_scan_start(ic); /* notify driver */
423 ss->ss_scanend = ticks + duration;
424 ss->ss_iflags |= ISCAN_START;
425 callout_reset(&ss->ss_scan_timer, 0, scan_next, ss);
426 } else
427 scan_restart_pwrsav(ss);
428 return 1;
429}
430
431static void
432copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
433 int nssid, const struct ieee80211_scan_ssid ssids[])
434{
435 if (nssid > IEEE80211_SCAN_MAX_SSID) {
436 /* XXX printf */
437 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
438 "%s: too many ssid %d, ignoring all of them\n",
439 __func__, nssid);
440 return;
441 }
442 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
443 ss->ss_nssid = nssid;
444}
445
446/*
447 * Start a scan unless one is already going.
448 */
449static int
450start_scan_locked(const struct ieee80211_scanner *scan,
451 struct ieee80211vap *vap, int flags, u_int duration,
452 u_int mindwell, u_int maxdwell,
453 u_int nssid, const struct ieee80211_scan_ssid ssids[])
454{
455 struct ieee80211com *ic = vap->iv_ic;
456 struct ieee80211_scan_state *ss = ic->ic_scan;
457
458 IEEE80211_LOCK_ASSERT(ic);
459
460 if (ic->ic_flags & IEEE80211_F_CSAPENDING) {
461 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
462 "%s: scan inhibited by pending channel change\n", __func__);
463 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
464 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
465 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n"
466 , __func__
467 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
468 , duration, mindwell, maxdwell
469 , ieee80211_phymode_name[vap->iv_des_mode]
470 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
471 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
472 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
473 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : ""
474 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
475 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
476 );
477
478 scan_update_locked(vap, scan);
479 if (ss->ss_ops != NULL) {
480 if ((flags & IEEE80211_SCAN_NOSSID) == 0)
481 copy_ssid(vap, ss, nssid, ssids);
482
483 /* NB: top 4 bits for internal use */
484 ss->ss_flags = flags & 0xfff;
485 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
486 vap->iv_stats.is_scan_active++;
487 else
488 vap->iv_stats.is_scan_passive++;
489 if (flags & IEEE80211_SCAN_FLUSH)
490 ss->ss_ops->scan_flush(ss);
491
492 /* NB: flush frames rx'd before 1st channel change */
493 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
494 ss->ss_next = 0;
495 ss->ss_mindwell = mindwell;
496 ss->ss_maxdwell = maxdwell;
497 ss->ss_ops->scan_start(ss, vap);
498#ifdef IEEE80211_DEBUG
499 if (ieee80211_msg_scan(vap))
500 scan_dump(ss);
501#endif /* IEEE80211_DEBUG */
502 if (scan_restart(SCAN_PRIVATE(ss), duration))
503 ic->ic_flags |= IEEE80211_F_SCAN;
504 }
505 } else {
506 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
507 "%s: %s scan already in progress\n", __func__,
508 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
509 }
510 return (ic->ic_flags & IEEE80211_F_SCAN);
511}
512
513/*
514 * Start a scan unless one is already going.
515 */
516int
517ieee80211_start_scan(struct ieee80211vap *vap, int flags,
518 u_int duration, u_int mindwell, u_int maxdwell,
519 u_int nssid, const struct ieee80211_scan_ssid ssids[])
520{
521 struct ieee80211com *ic = vap->iv_ic;
522 const struct ieee80211_scanner *scan;
523 int result;
524
525 scan = ieee80211_scanner_get(vap->iv_opmode);
526 if (scan == NULL) {
527 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
528 "%s: no scanner support for %s mode\n",
529 __func__, ieee80211_opmode_name[vap->iv_opmode]);
530 /* XXX stat */
531 return 0;
532 }
533
534 IEEE80211_LOCK(ic);
535 result = start_scan_locked(scan, vap, flags, duration,
536 mindwell, maxdwell, nssid, ssids);
537 IEEE80211_UNLOCK(ic);
538
539 return result;
540}
541
542/*
543 * Check the scan cache for an ap/channel to use; if that
544 * fails then kick off a new scan.
545 */
546int
547ieee80211_check_scan(struct ieee80211vap *vap, int flags,
548 u_int duration, u_int mindwell, u_int maxdwell,
549 u_int nssid, const struct ieee80211_scan_ssid ssids[])
550{
551 struct ieee80211com *ic = vap->iv_ic;
552 struct ieee80211_scan_state *ss = ic->ic_scan;
553 const struct ieee80211_scanner *scan;
554 int result;
555
556 scan = ieee80211_scanner_get(vap->iv_opmode);
557 if (scan == NULL) {
558 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
559 "%s: no scanner support for %s mode\n",
560 __func__, vap->iv_opmode);
561 /* XXX stat */
562 return 0;
563 }
564
565 /*
566 * Check if there's a list of scan candidates already.
567 * XXX want more than the ap we're currently associated with
568 */
569
570 IEEE80211_LOCK(ic);
571 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
572 "%s: %s scan, %s%s%s%s%s\n"
573 , __func__
574 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
575 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
576 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
577 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
578 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
579 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
580 );
581
582 if (ss->ss_ops != scan) {
583 /* XXX re-use cache contents? e.g. adhoc<->sta */
584 flags |= IEEE80211_SCAN_FLUSH;
585 }
586 scan_update_locked(vap, scan);
587 if (ss->ss_ops != NULL) {
588 /* XXX verify ss_ops matches vap->iv_opmode */
589 if ((flags & IEEE80211_SCAN_NOSSID) == 0) {
590 /*
591 * Update the ssid list and mark flags so if
592 * we call start_scan it doesn't duplicate work.
593 */
594 copy_ssid(vap, ss, nssid, ssids);
595 flags |= IEEE80211_SCAN_NOSSID;
596 }
597 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 &&
598 (flags & IEEE80211_SCAN_FLUSH) == 0 &&
599 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
600 /*
601 * We're not currently scanning and the cache is
602 * deemed hot enough to consult. Lock out others
603 * by marking IEEE80211_F_SCAN while we decide if
604 * something is already in the scan cache we can
605 * use. Also discard any frames that might come
606 * in while temporarily marked as scanning.
607 */
608 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
609 ic->ic_flags |= IEEE80211_F_SCAN;
610
611 /* NB: need to use supplied flags in check */
612 ss->ss_flags = flags & 0xff;
613 result = ss->ss_ops->scan_end(ss, vap);
614
615 ic->ic_flags &= ~IEEE80211_F_SCAN;
616 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD;
617 if (result) {
618 ieee80211_notify_scan_done(vap);
619 IEEE80211_UNLOCK(ic);
620 return 1;
621 }
622 }
623 }
624 result = start_scan_locked(scan, vap, flags, duration,
625 mindwell, maxdwell, nssid, ssids);
626 IEEE80211_UNLOCK(ic);
627
628 return result;
629}
630
631/*
632 * Check the scan cache for an ap/channel to use; if that fails
633 * then kick off a scan using the current settings.
634 */
635int
636ieee80211_check_scan_current(struct ieee80211vap *vap)
637{
638 return ieee80211_check_scan(vap,
639 IEEE80211_SCAN_ACTIVE,
640 IEEE80211_SCAN_FOREVER, 0, 0,
641 vap->iv_des_nssid, vap->iv_des_ssid);
642}
643
644/*
645 * Restart a previous scan. If the previous scan completed
646 * then we start again using the existing channel list.
647 */
648int
649ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
650{
651 struct ieee80211com *ic = vap->iv_ic;
652 struct ieee80211_scan_state *ss = ic->ic_scan;
653 const struct ieee80211_scanner *scan;
654
655 scan = ieee80211_scanner_get(vap->iv_opmode);
656 if (scan == NULL) {
657 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
658 "%s: no scanner support for %s mode\n",
659 __func__, vap->iv_opmode);
660 /* XXX stat */
661 return 0;
662 }
663
664 IEEE80211_LOCK(ic);
665 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
666 u_int duration;
667 /*
668 * Go off-channel for a fixed interval that is large
669 * enough to catch most ap's but short enough that
670 * we can return on-channel before our listen interval
671 * expires.
672 */
673 duration = IEEE80211_SCAN_OFFCHANNEL;
674
675 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
676 "%s: %s scan, ticks %u duration %lu\n", __func__,
677 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive",
678 ticks, duration);
679
680 scan_update_locked(vap, scan);
681 if (ss->ss_ops != NULL) {
682 ss->ss_vap = vap;
683 /*
684 * A background scan does not select a new sta; it
685 * just refreshes the scan cache. Also, indicate
686 * the scan logic should follow the beacon schedule:
687 * we go off-channel and scan for a while, then
688 * return to the bss channel to receive a beacon,
689 * then go off-channel again. All during this time
690 * we notify the ap we're in power save mode. When
691 * the scan is complete we leave power save mode.
692 * If any beacon indicates there are frames pending
693 * for us then we drop out of power save mode
694 * (and background scan) automatically by way of the
695 * usual sta power save logic.
696 */
697 ss->ss_flags |= IEEE80211_SCAN_NOPICK
698 | IEEE80211_SCAN_BGSCAN
699 | flags
700 ;
701 /* if previous scan completed, restart */
702 if (ss->ss_next >= ss->ss_last) {
703 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
704 vap->iv_stats.is_scan_active++;
705 else
706 vap->iv_stats.is_scan_passive++;
707 /*
708 * NB: beware of the scan cache being flushed;
709 * if the channel list is empty use the
710 * scan_start method to populate it.
711 */
712 ss->ss_next = 0;
713 if (ss->ss_last != 0)
714 ss->ss_ops->scan_restart(ss, vap);
715 else {
716 ss->ss_ops->scan_start(ss, vap);
717#ifdef IEEE80211_DEBUG
718 if (ieee80211_msg_scan(vap))
719 scan_dump(ss);
720#endif /* IEEE80211_DEBUG */
721 }
722 }
723 /* NB: flush frames rx'd before 1st channel change */
724 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
725 ss->ss_maxdwell = duration;
726 if (scan_restart(SCAN_PRIVATE(ss), duration)) {
727 ic->ic_flags |= IEEE80211_F_SCAN;
728 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN;
729 }
730 } else {
731 /* XXX msg+stat */
732 }
733 } else {
734 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
735 "%s: %s scan already in progress\n", __func__,
736 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
737 }
738 IEEE80211_UNLOCK(ic);
739
740 /* NB: racey, does it matter? */
741 return (ic->ic_flags & IEEE80211_F_SCAN);
742}
743
744/*
745 * Cancel any scan currently going on for the specified vap.
746 */
747void
748ieee80211_cancel_scan(struct ieee80211vap *vap)
749{
750 struct ieee80211com *ic = vap->iv_ic;
751 struct ieee80211_scan_state *ss = ic->ic_scan;
752
753 IEEE80211_LOCK(ic);
754 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
755 ss->ss_vap == vap &&
756 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
757 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
758 "%s: cancel %s scan\n", __func__,
759 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
760 "active" : "passive");
761
762 /* clear bg scan NOPICK and mark cancel request */
763 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
764 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
765 /* force it to fire asap */
766 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
767 0, scan_next, ss);
768 }
769 IEEE80211_UNLOCK(ic);
770}
771
772/*
773 * Cancel any scan currently going on.
774 */
775void
776ieee80211_cancel_anyscan(struct ieee80211vap *vap)
777{
778 struct ieee80211com *ic = vap->iv_ic;
779 struct ieee80211_scan_state *ss = ic->ic_scan;
780
781 IEEE80211_LOCK(ic);
782 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
783 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
784 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
785 "%s: cancel %s scan\n", __func__,
786 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
787 "active" : "passive");
788
789 /* clear bg scan NOPICK and mark cancel request */
790 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
791 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
792 /* force it to fire asap */
793 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
794 0, scan_next, ss);
795 }
796 IEEE80211_UNLOCK(ic);
797}
798
799/*
800 * Public access to scan_next for drivers that manage
801 * scanning themselves (e.g. for firmware-based devices).
802 */
803void
804ieee80211_scan_next(struct ieee80211vap *vap)
805{
806 struct ieee80211com *ic = vap->iv_ic;
807 struct ieee80211_scan_state *ss = ic->ic_scan;
808
809 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss);
810}
811
812/*
813 * Public access to scan_next for drivers that are not able to scan single
814 * channels (e.g. for firmware-based devices).
815 */
816void
817ieee80211_scan_done(struct ieee80211vap *vap)
818{
819 struct ieee80211com *ic = vap->iv_ic;
820 struct ieee80211_scan_state *ss;
821
822 IEEE80211_LOCK(ic);
823 ss = ic->ic_scan;
824 ss->ss_next = ss->ss_last; /* all channels are complete */
825 scan_next(ss);
826 IEEE80211_UNLOCK(ic);
827}
828
829/*
830 * Probe the curent channel, if allowed, while scanning.
831 * If the channel is not marked passive-only then send
832 * a probe request immediately. Otherwise mark state and
833 * listen for beacons on the channel; if we receive something
834 * then we'll transmit a probe request.
835 */
836void
837ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
838{
839 struct ieee80211com *ic = vap->iv_ic;
840 struct ieee80211_scan_state *ss = ic->ic_scan;
841 struct ifnet *ifp = vap->iv_ifp;
842 int i;
843
844 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
845 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
846 return;
847 }
848 /*
849 * Send directed probe requests followed by any
850 * broadcast probe request.
851 * XXX remove dependence on ic/vap->iv_bss
852 */
853 for (i = 0; i < ss->ss_nssid; i++)
854 ieee80211_send_probereq(vap->iv_bss,
855 vap->iv_myaddr, ifp->if_broadcastaddr,
856 ifp->if_broadcastaddr,
857 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len);
858 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0)
859 ieee80211_send_probereq(vap->iv_bss,
860 vap->iv_myaddr, ifp->if_broadcastaddr,
861 ifp->if_broadcastaddr,
862 "", 0);
863}
864
865/*
866 * Scan curchan. If this is an active scan and the channel
867 * is not marked passive then send probe request frame(s).
868 * Arrange for the channel change after maxdwell ticks.
869 */
870static void
871scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
872{
873 struct ieee80211vap *vap = ss->ss_vap;
874
875 IEEE80211_LOCK_ASSERT(vap->iv_ic);
876
877 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
878 ieee80211_probe_curchan(vap, 0);
879 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
880 maxdwell, scan_next, ss);
881}
882
883/*
884 * Handle mindwell requirements completed; initiate a channel
885 * change to the next channel asap.
886 */
887static void
888scan_mindwell(struct ieee80211_scan_state *ss)
889{
890 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss);
891}
892
893/*
894 * Switch to the next channel marked for scanning.
895 */
896static void
897scan_next(void *arg)
898{
899#define ISCAN_REP (ISCAN_MINDWELL | ISCAN_START | ISCAN_DISCARD)
900 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
901 struct ieee80211vap *vap = ss->ss_vap;
902 struct ieee80211com *ic = vap->iv_ic;
903 struct ieee80211_channel *chan;
904 unsigned long maxdwell, scanend;
905 int scandone;
906
907 IEEE80211_LOCK_ASSERT(ic);
908
909 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0)
910 return;
911again:
912 scandone = (ss->ss_next >= ss->ss_last) ||
913 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0;
914 scanend = SCAN_PRIVATE(ss)->ss_scanend;
915 if (!scandone &&
916 (ss->ss_flags & IEEE80211_SCAN_GOTPICK) == 0 &&
917 ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_START) ||
918 time_before(ticks + ss->ss_mindwell, scanend))) {
919 chan = ss->ss_chans[ss->ss_next++];
920
921 /*
922 * Watch for truncation due to the scan end time.
923 */
924 if (time_after(ticks + ss->ss_maxdwell, scanend))
925 maxdwell = scanend - ticks;
926 else
927 maxdwell = ss->ss_maxdwell;
928
929 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
930 "%s: chan %3d%c -> %3d%c [%s, dwell min %lu max %lu]\n",
931 __func__,
932 ieee80211_chan2ieee(ic, ic->ic_curchan),
933 channel_type(ic->ic_curchan),
934 ieee80211_chan2ieee(ic, chan), channel_type(chan),
935 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
936 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
937 "active" : "passive",
938 ss->ss_mindwell, maxdwell);
939
940 /*
941 * Potentially change channel and phy mode.
942 */
943 change_channel(ic, chan);
944
945 /*
946 * Scan curchan. Drivers for "intelligent hardware"
947 * override ic_scan_curchan to tell the device to do
948 * the work. Otherwise we manage the work outselves;
949 * sending a probe request (as needed), and arming the
950 * timeout to switch channels after maxdwell ticks.
951 */
952 ic->ic_scan_curchan(ss, maxdwell);
953
954 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell;
955 /* clear mindwell lock and initial channel change flush */
956 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
957 } else {
958 ic->ic_scan_end(ic); /* notify driver */
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_setcurchan(ic, ic->ic_bsschan);
970 /* clear internal flags and any indication of a pick */
971 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
972 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK;
973
974 /*
975 * If not canceled and scan completed, do post-processing.
976 * If the callback function returns 0, then it wants to
977 * continue/restart scanning. Unfortunately we needed to
978 * notify the driver to end the scan above to avoid having
979 * rx frames alter the scan candidate list.
980 */
981 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 &&
982 !ss->ss_ops->scan_end(ss, vap) &&
983 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 &&
984 time_before(ticks + ss->ss_mindwell, scanend)) {
985 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
986 "%s: done, restart "
987 "[ticks %u, dwell min %lu scanend %lu]\n",
988 __func__,
989 ticks, ss->ss_mindwell, scanend);
990 ss->ss_next = 0; /* reset to begining */
991 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
992 vap->iv_stats.is_scan_active++;
993 else
994 vap->iv_stats.is_scan_passive++;
995
996 ss->ss_ops->scan_restart(ss, vap); /* XXX? */
997 ic->ic_scan_start(ic); /* notify driver */
998 goto again;
999 } else {
1000 /* past here, scandone is ``true'' if not in bg mode */
1001 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0)
1002 scandone = 1;
1003
1004 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1005 "%s: %s, "
1006 "[ticks %u, dwell min %lu scanend %lu]\n",
1007 __func__, scandone ? "done" : "stopped",
1008 ticks, ss->ss_mindwell, scanend);
1009
1010 /*
1011 * Clear the SCAN bit first in case frames are
1012 * pending on the station power save queue. If
1013 * we defer this then the dispatch of the frames
1014 * may generate a request to cancel scanning.
1015 */
1016 ic->ic_flags &= ~IEEE80211_F_SCAN;
1017 /*
1018 * Drop out of power save mode when a scan has
1019 * completed. If this scan was prematurely terminated
1020 * because it is a background scan then don't notify
1021 * the ap; we'll either return to scanning after we
1022 * receive the beacon frame or we'll drop out of power
1023 * save mode because the beacon indicates we have frames
1024 * waiting for us.
1025 */
1026 if (scandone) {
1027 ieee80211_sta_pwrsave(vap, 0);
1028 if (ss->ss_next >= ss->ss_last) {
1029 ieee80211_notify_scan_done(vap);
1030 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN;
1031 }
1032 }
1033 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_CANCEL;
1034 ss->ss_flags &=
1035 ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST);
1036 }
1037 }
1038#undef ISCAN_REP
1039}
1040
1041#ifdef IEEE80211_DEBUG
1042static void
1043dump_country(const uint8_t *ie)
1044{
1045 const struct ieee80211_country_ie *cie =
1046 (const struct ieee80211_country_ie *) ie;
1047 int i, nbands, schan, nchan;
1048
1049 if (cie->len < 3) {
1050 printf(" <bogus country ie, len %d>", cie->len);
1051 return;
1052 }
1053 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
1054 nbands = (cie->len - 3) / sizeof(cie->band[0]);
1055 for (i = 0; i < nbands; i++) {
1056 schan = cie->band[i].schan;
1057 nchan = cie->band[i].nchan;
1058 if (nchan != 1)
1059 printf(" %u-%u,%u", schan, schan + nchan-1,
1060 cie->band[i].maxtxpwr);
1061 else
1062 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
1063 }
1064 printf("]");
1065}
1066
1067static void
1068dump_probe_beacon(uint8_t subtype, int isnew,
1069 const uint8_t mac[IEEE80211_ADDR_LEN],
1070 const struct ieee80211_scanparams *sp, int rssi)
1071{
1072
1073 printf("[%s] %s%s on chan %u (bss chan %u) ",
1074 ether_sprintf(mac), isnew ? "new " : "",
1075 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1076 sp->chan, sp->bchan);
1077 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1078 printf(" rssi %d\n", rssi);
1079
1080 if (isnew) {
1081 printf("[%s] caps 0x%x bintval %u erp 0x%x",
1082 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1083 if (sp->country != NULL)
1084 dump_country(sp->country);
1085 printf("\n");
1086 }
1087}
1088#endif /* IEEE80211_DEBUG */
1089
1090/*
1091 * Process a beacon or probe response frame.
1092 */
1093void
1094ieee80211_add_scan(struct ieee80211vap *vap,
1095 const struct ieee80211_scanparams *sp,
1096 const struct ieee80211_frame *wh,
1097 int subtype, int rssi, int noise, int rstamp)
1098{
1099 struct ieee80211com *ic = vap->iv_ic;
1100 struct ieee80211_scan_state *ss = ic->ic_scan;
1101
1102 /* XXX locking */
1103 /*
1104 * Frames received during startup are discarded to avoid
1105 * using scan state setup on the initial entry to the timer
1106 * callback. This can occur because the device may enable
1107 * rx prior to our doing the initial channel change in the
1108 * timer routine.
1109 */
1110 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD)
1111 return;
1112#ifdef IEEE80211_DEBUG
1113 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN))
1114 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi);
1115#endif
1116 if (ss->ss_ops != NULL &&
1117 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise, rstamp)) {
1118 /*
1119 * If we've reached the min dwell time terminate
1120 * the timer so we'll switch to the next channel.
1121 */
1122 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 &&
1123 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) {
1124 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1125 "%s: chan %3d%c min dwell met (%u > %lu)\n",
1126 __func__,
1127 ieee80211_chan2ieee(ic, ic->ic_curchan),
1128 channel_type(ic->ic_curchan),
1129 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell);
1130 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL;
1131 /*
1132 * NB: trigger at next clock tick or wait for the
1133 * hardware.
1134 */
1135 ic->ic_scan_mindwell(ss);
1136 }
1137 }
1138}
1139
1140/*
1141 * Timeout/age scan cache entries; called from sta timeout
1142 * timer (XXX should be self-contained).
1143 */
1144void
1145ieee80211_scan_timeout(struct ieee80211com *ic)
1146{
1147 struct ieee80211_scan_state *ss = ic->ic_scan;
1148
1149 if (ss->ss_ops != NULL)
1150 ss->ss_ops->scan_age(ss);
1151}
1152
1153/*
1154 * Mark a scan cache entry after a successful associate.
1155 */
1156void
1157ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
1158{
1159 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1160
1161 if (ss->ss_ops != NULL) {
1162 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
1163 mac, "%s", __func__);
1164 ss->ss_ops->scan_assoc_success(ss, mac);
1165 }
1166}
1167
1168/*
1169 * Demerit a scan cache entry after failing to associate.
1170 */
1171void
1172ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
1173 const uint8_t mac[], int reason)
1174{
1175 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1176
1177 if (ss->ss_ops != NULL) {
1178 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
1179 "%s: reason %u", __func__, reason);
1180 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
1181 }
1182}
1183
1184/*
1185 * Iterate over the contents of the scan cache.
1186 */
1187void
1188ieee80211_scan_iterate(struct ieee80211vap *vap,
1189 ieee80211_scan_iter_func *f, void *arg)
1190{
1191 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1192
1193 if (ss->ss_ops != NULL)
1194 ss->ss_ops->scan_iterate(ss, f, arg);
1195}
1196
1197/*
1198 * Flush the contents of the scan cache.
1199 */
1200void
1201ieee80211_scan_flush(struct ieee80211vap *vap)
1202{
1203 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1204
1205 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
1206 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
1207 ss->ss_ops->scan_flush(ss);
1208 }
1209}
1210
1211/*
1212 * Check the scan cache for an ap/channel to use; if that
1213 * fails then kick off a new scan.
1214 */
1215struct ieee80211_channel *
1216ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
1217{
1218 struct ieee80211_scan_state *ss = ic->ic_scan;
1219
1220 IEEE80211_LOCK_ASSERT(ic);
1221
1222 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
1223 /* XXX printf? */
1224 return NULL;
1225 }
1226 if (ss->ss_ops->scan_pickchan == NULL) {
1227 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
1228 "%s: scan module does not support picking a channel, "
1229 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
1230 return NULL;
1231 }
1232 return ss->ss_ops->scan_pickchan(ss, flags);
1233}
126 }
127}
128
129static __inline void
130setparams(struct ieee80211_roamparam *rp, int8_t rssi, uint8_t txrate)
131{
132 rp->rssi = rssi;
133 rp->rate = txrate;
134}
135
136void
137ieee80211_scan_vattach(struct ieee80211vap *vap)
138{
139 struct ieee80211com *ic = vap->iv_ic;
140
141 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
142 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
143 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
144
145 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
146
147 /* NB: only set supported modes so user apps can identify */
148 if (isset(ic->ic_modecaps, IEEE80211_MODE_11A))
149 setparams(&vap->iv_roamparms[IEEE80211_MODE_11A],
150 ROAM_RSSI_11A_DEFAULT, ROAM_RATE_11A_DEFAULT);
151 if (isset(ic->ic_modecaps, IEEE80211_MODE_11G))
152 setparams(&vap->iv_roamparms[IEEE80211_MODE_11G],
153 ROAM_RSSI_11B_DEFAULT, ROAM_RATE_11B_DEFAULT);
154 if (isset(ic->ic_modecaps, IEEE80211_MODE_11B))
155 setparams(&vap->iv_roamparms[IEEE80211_MODE_11B],
156 ROAM_RSSI_11BONLY_DEFAULT, ROAM_RATE_11BONLY_DEFAULT);
157 /* NB: default turbo controls to be the same as !turbo */
158 if (isset(ic->ic_modecaps, IEEE80211_MODE_TURBO_A))
159 vap->iv_roamparms[IEEE80211_MODE_TURBO_A] =
160 vap->iv_roamparms[IEEE80211_MODE_11A];
161 if (isset(ic->ic_modecaps, IEEE80211_MODE_TURBO_G))
162 vap->iv_roamparms[IEEE80211_MODE_TURBO_G] =
163 vap->iv_roamparms[IEEE80211_MODE_11G];
164 if (isset(ic->ic_modecaps, IEEE80211_MODE_STURBO_A))
165 vap->iv_roamparms[IEEE80211_MODE_STURBO_A] =
166 vap->iv_roamparms[IEEE80211_MODE_11A];
167 if (isset(ic->ic_modecaps, IEEE80211_MODE_11NA))
168 setparams(&vap->iv_roamparms[IEEE80211_MODE_11NA],
169 ROAM_RSSI_11A_DEFAULT, ROAM_MCS_11N_DEFAULT | 0x80);
170 if (isset(ic->ic_modecaps, IEEE80211_MODE_11NG))
171 setparams(&vap->iv_roamparms[IEEE80211_MODE_11NG],
172 ROAM_RSSI_11B_DEFAULT, ROAM_MCS_11N_DEFAULT | 0x80);
173}
174
175void
176ieee80211_scan_vdetach(struct ieee80211vap *vap)
177{
178 struct ieee80211com *ic = vap->iv_ic;
179 struct ieee80211_scan_state *ss;
180
181 IEEE80211_LOCK(ic);
182 ss = ic->ic_scan;
183 if (ss != NULL && ss->ss_vap == vap) {
184 if (ic->ic_flags & IEEE80211_F_SCAN) {
185 /* XXX callout_drain */
186 callout_stop(&SCAN_PRIVATE(ss)->ss_scan_timer);
187 ic->ic_flags &= ~IEEE80211_F_SCAN;
188 }
189 if (ss->ss_ops != NULL) {
190 ss->ss_ops->scan_detach(ss);
191 ss->ss_ops = NULL;
192 }
193 ss->ss_vap = NULL;
194 }
195 IEEE80211_UNLOCK(ic);
196}
197
198/*
199 * Simple-minded scanner module support.
200 */
201static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
202 "wlan_scan_sta", /* IEEE80211_M_IBSS */
203 "wlan_scan_sta", /* IEEE80211_M_STA */
204 "wlan_scan_wds", /* IEEE80211_M_WDS */
205 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
206 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
207 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
208};
209static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
210
211const struct ieee80211_scanner *
212ieee80211_scanner_get(enum ieee80211_opmode mode)
213{
214 if (mode >= IEEE80211_OPMODE_MAX)
215 return NULL;
216 if (scanners[mode] == NULL)
217 ieee80211_load_module(scan_modnames[mode]);
218 return scanners[mode];
219}
220
221void
222ieee80211_scanner_register(enum ieee80211_opmode mode,
223 const struct ieee80211_scanner *scan)
224{
225 if (mode >= IEEE80211_OPMODE_MAX)
226 return;
227 scanners[mode] = scan;
228}
229
230void
231ieee80211_scanner_unregister(enum ieee80211_opmode mode,
232 const struct ieee80211_scanner *scan)
233{
234 if (mode >= IEEE80211_OPMODE_MAX)
235 return;
236 if (scanners[mode] == scan)
237 scanners[mode] = NULL;
238}
239
240void
241ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
242{
243 int m;
244
245 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
246 if (scanners[m] == scan)
247 scanners[m] = NULL;
248}
249
250/*
251 * Update common scanner state to reflect the current
252 * operating mode. This is called when the state machine
253 * is transitioned to RUN state w/o scanning--e.g. when
254 * operating in monitor mode. The purpose of this is to
255 * ensure later callbacks find ss_ops set to properly
256 * reflect current operating mode.
257 */
258static void
259scan_update_locked(struct ieee80211vap *vap,
260 const struct ieee80211_scanner *scan)
261{
262 struct ieee80211com *ic = vap->iv_ic;
263 struct ieee80211_scan_state *ss = ic->ic_scan;
264
265 IEEE80211_LOCK_ASSERT(ic);
266
267#ifdef IEEE80211_DEBUG
268 if (ss->ss_vap != vap || ss->ss_ops != scan) {
269 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
270 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
271 __func__,
272 ss->ss_vap != NULL ?
273 ss->ss_vap->iv_ifp->if_xname : "none",
274 ss->ss_vap != NULL ?
275 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
276 vap->iv_ifp->if_xname,
277 ieee80211_opmode_name[vap->iv_opmode]);
278 }
279#endif
280 ss->ss_vap = vap;
281 if (ss->ss_ops != scan) {
282 /*
283 * Switch scanners; detach old, attach new. Special
284 * case where a single scan module implements multiple
285 * policies by using different scan ops but a common
286 * core. We assume if the old and new attach methods
287 * are identical then it's ok to just change ss_ops
288 * and not flush the internal state of the module.
289 */
290 if (scan == NULL || ss->ss_ops == NULL ||
291 ss->ss_ops->scan_attach != scan->scan_attach) {
292 if (ss->ss_ops != NULL)
293 ss->ss_ops->scan_detach(ss);
294 if (scan != NULL && !scan->scan_attach(ss)) {
295 /* XXX attach failure */
296 /* XXX stat+msg */
297 scan = NULL;
298 }
299 }
300 ss->ss_ops = scan;
301 }
302}
303
304static void
305change_channel(struct ieee80211com *ic,
306 struct ieee80211_channel *chan)
307{
308 ic->ic_curchan = chan;
309 ic->ic_set_channel(ic);
310}
311
312static char
313channel_type(const struct ieee80211_channel *c)
314{
315 if (IEEE80211_IS_CHAN_ST(c))
316 return 'S';
317 if (IEEE80211_IS_CHAN_108A(c))
318 return 'T';
319 if (IEEE80211_IS_CHAN_108G(c))
320 return 'G';
321 if (IEEE80211_IS_CHAN_HT(c))
322 return 'n';
323 if (IEEE80211_IS_CHAN_A(c))
324 return 'a';
325 if (IEEE80211_IS_CHAN_ANYG(c))
326 return 'g';
327 if (IEEE80211_IS_CHAN_B(c))
328 return 'b';
329 return 'f';
330}
331
332void
333ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
334{
335 struct ieee80211com *ic = ss->ss_vap->iv_ic;
336 const char *sep;
337 int i;
338
339 sep = "";
340 for (i = ss->ss_next; i < ss->ss_last; i++) {
341 const struct ieee80211_channel *c = ss->ss_chans[i];
342
343 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
344 channel_type(c));
345 sep = ", ";
346 }
347}
348
349#ifdef IEEE80211_DEBUG
350static void
351scan_dump(struct ieee80211_scan_state *ss)
352{
353 struct ieee80211vap *vap = ss->ss_vap;
354
355 if_printf(vap->iv_ifp, "scan set ");
356 ieee80211_scan_dump_channels(ss);
357 printf(" dwell min %lu max %lu\n", ss->ss_mindwell, ss->ss_maxdwell);
358}
359#endif /* IEEE80211_DEBUG */
360
361/*
362 * Enable station power save mode and start/restart the scanning thread.
363 */
364static void
365scan_restart_pwrsav(void *arg)
366{
367 struct scan_state *ss = (struct scan_state *) arg;
368 struct ieee80211vap *vap = ss->base.ss_vap;
369 struct ieee80211com *ic = vap->iv_ic;
370 int ticksdelay;
371
372 ieee80211_sta_pwrsave(vap, 1);
373 /*
374 * Use an initial 1ms delay so the null
375 * data frame has a chance to go out.
376 * XXX 1ms is a lot, better to trigger scan
377 * on tx complete.
378 */
379 ticksdelay = msecs_to_ticks(1);
380 if (ticksdelay < 1)
381 ticksdelay = 1;
382 ic->ic_scan_start(ic); /* notify driver */
383 ss->ss_scanend = ticks + ticksdelay + ss->ss_duration;
384 ss->ss_iflags |= ISCAN_START;
385 callout_reset(&ss->ss_scan_timer, ticksdelay, scan_next, ss);
386}
387
388/*
389 * Start/restart scanning. If we're operating in station mode
390 * and associated notify the ap we're going into power save mode
391 * and schedule a callback to initiate the work (where there's a
392 * better context for doing the work). Otherwise, start the scan
393 * directly.
394 */
395static int
396scan_restart(struct scan_state *ss, u_int duration)
397{
398 struct ieee80211vap *vap = ss->base.ss_vap;
399 struct ieee80211com *ic = vap->iv_ic;
400 int defer = 0;
401
402 if (ss->base.ss_next == ss->base.ss_last) {
403 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
404 "%s: no channels to scan\n", __func__);
405 return 0;
406 }
407 if (vap->iv_opmode == IEEE80211_M_STA &&
408 vap->iv_state == IEEE80211_S_RUN) {
409 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
410 /*
411 * Initiate power save before going off-channel.
412 * Note that we cannot do this directly because
413 * of locking issues; instead we defer it to a
414 * tasklet.
415 */
416 ss->ss_duration = duration;
417 defer = 1;
418 }
419 }
420
421 if (!defer) {
422 ic->ic_scan_start(ic); /* notify driver */
423 ss->ss_scanend = ticks + duration;
424 ss->ss_iflags |= ISCAN_START;
425 callout_reset(&ss->ss_scan_timer, 0, scan_next, ss);
426 } else
427 scan_restart_pwrsav(ss);
428 return 1;
429}
430
431static void
432copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
433 int nssid, const struct ieee80211_scan_ssid ssids[])
434{
435 if (nssid > IEEE80211_SCAN_MAX_SSID) {
436 /* XXX printf */
437 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
438 "%s: too many ssid %d, ignoring all of them\n",
439 __func__, nssid);
440 return;
441 }
442 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
443 ss->ss_nssid = nssid;
444}
445
446/*
447 * Start a scan unless one is already going.
448 */
449static int
450start_scan_locked(const struct ieee80211_scanner *scan,
451 struct ieee80211vap *vap, int flags, u_int duration,
452 u_int mindwell, u_int maxdwell,
453 u_int nssid, const struct ieee80211_scan_ssid ssids[])
454{
455 struct ieee80211com *ic = vap->iv_ic;
456 struct ieee80211_scan_state *ss = ic->ic_scan;
457
458 IEEE80211_LOCK_ASSERT(ic);
459
460 if (ic->ic_flags & IEEE80211_F_CSAPENDING) {
461 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
462 "%s: scan inhibited by pending channel change\n", __func__);
463 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
464 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
465 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n"
466 , __func__
467 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
468 , duration, mindwell, maxdwell
469 , ieee80211_phymode_name[vap->iv_des_mode]
470 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
471 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
472 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
473 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : ""
474 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
475 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
476 );
477
478 scan_update_locked(vap, scan);
479 if (ss->ss_ops != NULL) {
480 if ((flags & IEEE80211_SCAN_NOSSID) == 0)
481 copy_ssid(vap, ss, nssid, ssids);
482
483 /* NB: top 4 bits for internal use */
484 ss->ss_flags = flags & 0xfff;
485 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
486 vap->iv_stats.is_scan_active++;
487 else
488 vap->iv_stats.is_scan_passive++;
489 if (flags & IEEE80211_SCAN_FLUSH)
490 ss->ss_ops->scan_flush(ss);
491
492 /* NB: flush frames rx'd before 1st channel change */
493 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
494 ss->ss_next = 0;
495 ss->ss_mindwell = mindwell;
496 ss->ss_maxdwell = maxdwell;
497 ss->ss_ops->scan_start(ss, vap);
498#ifdef IEEE80211_DEBUG
499 if (ieee80211_msg_scan(vap))
500 scan_dump(ss);
501#endif /* IEEE80211_DEBUG */
502 if (scan_restart(SCAN_PRIVATE(ss), duration))
503 ic->ic_flags |= IEEE80211_F_SCAN;
504 }
505 } else {
506 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
507 "%s: %s scan already in progress\n", __func__,
508 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
509 }
510 return (ic->ic_flags & IEEE80211_F_SCAN);
511}
512
513/*
514 * Start a scan unless one is already going.
515 */
516int
517ieee80211_start_scan(struct ieee80211vap *vap, int flags,
518 u_int duration, u_int mindwell, u_int maxdwell,
519 u_int nssid, const struct ieee80211_scan_ssid ssids[])
520{
521 struct ieee80211com *ic = vap->iv_ic;
522 const struct ieee80211_scanner *scan;
523 int result;
524
525 scan = ieee80211_scanner_get(vap->iv_opmode);
526 if (scan == NULL) {
527 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
528 "%s: no scanner support for %s mode\n",
529 __func__, ieee80211_opmode_name[vap->iv_opmode]);
530 /* XXX stat */
531 return 0;
532 }
533
534 IEEE80211_LOCK(ic);
535 result = start_scan_locked(scan, vap, flags, duration,
536 mindwell, maxdwell, nssid, ssids);
537 IEEE80211_UNLOCK(ic);
538
539 return result;
540}
541
542/*
543 * Check the scan cache for an ap/channel to use; if that
544 * fails then kick off a new scan.
545 */
546int
547ieee80211_check_scan(struct ieee80211vap *vap, int flags,
548 u_int duration, u_int mindwell, u_int maxdwell,
549 u_int nssid, const struct ieee80211_scan_ssid ssids[])
550{
551 struct ieee80211com *ic = vap->iv_ic;
552 struct ieee80211_scan_state *ss = ic->ic_scan;
553 const struct ieee80211_scanner *scan;
554 int result;
555
556 scan = ieee80211_scanner_get(vap->iv_opmode);
557 if (scan == NULL) {
558 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
559 "%s: no scanner support for %s mode\n",
560 __func__, vap->iv_opmode);
561 /* XXX stat */
562 return 0;
563 }
564
565 /*
566 * Check if there's a list of scan candidates already.
567 * XXX want more than the ap we're currently associated with
568 */
569
570 IEEE80211_LOCK(ic);
571 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
572 "%s: %s scan, %s%s%s%s%s\n"
573 , __func__
574 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
575 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
576 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
577 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
578 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
579 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
580 );
581
582 if (ss->ss_ops != scan) {
583 /* XXX re-use cache contents? e.g. adhoc<->sta */
584 flags |= IEEE80211_SCAN_FLUSH;
585 }
586 scan_update_locked(vap, scan);
587 if (ss->ss_ops != NULL) {
588 /* XXX verify ss_ops matches vap->iv_opmode */
589 if ((flags & IEEE80211_SCAN_NOSSID) == 0) {
590 /*
591 * Update the ssid list and mark flags so if
592 * we call start_scan it doesn't duplicate work.
593 */
594 copy_ssid(vap, ss, nssid, ssids);
595 flags |= IEEE80211_SCAN_NOSSID;
596 }
597 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 &&
598 (flags & IEEE80211_SCAN_FLUSH) == 0 &&
599 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
600 /*
601 * We're not currently scanning and the cache is
602 * deemed hot enough to consult. Lock out others
603 * by marking IEEE80211_F_SCAN while we decide if
604 * something is already in the scan cache we can
605 * use. Also discard any frames that might come
606 * in while temporarily marked as scanning.
607 */
608 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
609 ic->ic_flags |= IEEE80211_F_SCAN;
610
611 /* NB: need to use supplied flags in check */
612 ss->ss_flags = flags & 0xff;
613 result = ss->ss_ops->scan_end(ss, vap);
614
615 ic->ic_flags &= ~IEEE80211_F_SCAN;
616 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD;
617 if (result) {
618 ieee80211_notify_scan_done(vap);
619 IEEE80211_UNLOCK(ic);
620 return 1;
621 }
622 }
623 }
624 result = start_scan_locked(scan, vap, flags, duration,
625 mindwell, maxdwell, nssid, ssids);
626 IEEE80211_UNLOCK(ic);
627
628 return result;
629}
630
631/*
632 * Check the scan cache for an ap/channel to use; if that fails
633 * then kick off a scan using the current settings.
634 */
635int
636ieee80211_check_scan_current(struct ieee80211vap *vap)
637{
638 return ieee80211_check_scan(vap,
639 IEEE80211_SCAN_ACTIVE,
640 IEEE80211_SCAN_FOREVER, 0, 0,
641 vap->iv_des_nssid, vap->iv_des_ssid);
642}
643
644/*
645 * Restart a previous scan. If the previous scan completed
646 * then we start again using the existing channel list.
647 */
648int
649ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
650{
651 struct ieee80211com *ic = vap->iv_ic;
652 struct ieee80211_scan_state *ss = ic->ic_scan;
653 const struct ieee80211_scanner *scan;
654
655 scan = ieee80211_scanner_get(vap->iv_opmode);
656 if (scan == NULL) {
657 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
658 "%s: no scanner support for %s mode\n",
659 __func__, vap->iv_opmode);
660 /* XXX stat */
661 return 0;
662 }
663
664 IEEE80211_LOCK(ic);
665 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
666 u_int duration;
667 /*
668 * Go off-channel for a fixed interval that is large
669 * enough to catch most ap's but short enough that
670 * we can return on-channel before our listen interval
671 * expires.
672 */
673 duration = IEEE80211_SCAN_OFFCHANNEL;
674
675 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
676 "%s: %s scan, ticks %u duration %lu\n", __func__,
677 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive",
678 ticks, duration);
679
680 scan_update_locked(vap, scan);
681 if (ss->ss_ops != NULL) {
682 ss->ss_vap = vap;
683 /*
684 * A background scan does not select a new sta; it
685 * just refreshes the scan cache. Also, indicate
686 * the scan logic should follow the beacon schedule:
687 * we go off-channel and scan for a while, then
688 * return to the bss channel to receive a beacon,
689 * then go off-channel again. All during this time
690 * we notify the ap we're in power save mode. When
691 * the scan is complete we leave power save mode.
692 * If any beacon indicates there are frames pending
693 * for us then we drop out of power save mode
694 * (and background scan) automatically by way of the
695 * usual sta power save logic.
696 */
697 ss->ss_flags |= IEEE80211_SCAN_NOPICK
698 | IEEE80211_SCAN_BGSCAN
699 | flags
700 ;
701 /* if previous scan completed, restart */
702 if (ss->ss_next >= ss->ss_last) {
703 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
704 vap->iv_stats.is_scan_active++;
705 else
706 vap->iv_stats.is_scan_passive++;
707 /*
708 * NB: beware of the scan cache being flushed;
709 * if the channel list is empty use the
710 * scan_start method to populate it.
711 */
712 ss->ss_next = 0;
713 if (ss->ss_last != 0)
714 ss->ss_ops->scan_restart(ss, vap);
715 else {
716 ss->ss_ops->scan_start(ss, vap);
717#ifdef IEEE80211_DEBUG
718 if (ieee80211_msg_scan(vap))
719 scan_dump(ss);
720#endif /* IEEE80211_DEBUG */
721 }
722 }
723 /* NB: flush frames rx'd before 1st channel change */
724 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
725 ss->ss_maxdwell = duration;
726 if (scan_restart(SCAN_PRIVATE(ss), duration)) {
727 ic->ic_flags |= IEEE80211_F_SCAN;
728 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN;
729 }
730 } else {
731 /* XXX msg+stat */
732 }
733 } else {
734 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
735 "%s: %s scan already in progress\n", __func__,
736 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
737 }
738 IEEE80211_UNLOCK(ic);
739
740 /* NB: racey, does it matter? */
741 return (ic->ic_flags & IEEE80211_F_SCAN);
742}
743
744/*
745 * Cancel any scan currently going on for the specified vap.
746 */
747void
748ieee80211_cancel_scan(struct ieee80211vap *vap)
749{
750 struct ieee80211com *ic = vap->iv_ic;
751 struct ieee80211_scan_state *ss = ic->ic_scan;
752
753 IEEE80211_LOCK(ic);
754 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
755 ss->ss_vap == vap &&
756 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
757 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
758 "%s: cancel %s scan\n", __func__,
759 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
760 "active" : "passive");
761
762 /* clear bg scan NOPICK and mark cancel request */
763 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
764 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
765 /* force it to fire asap */
766 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
767 0, scan_next, ss);
768 }
769 IEEE80211_UNLOCK(ic);
770}
771
772/*
773 * Cancel any scan currently going on.
774 */
775void
776ieee80211_cancel_anyscan(struct ieee80211vap *vap)
777{
778 struct ieee80211com *ic = vap->iv_ic;
779 struct ieee80211_scan_state *ss = ic->ic_scan;
780
781 IEEE80211_LOCK(ic);
782 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
783 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
784 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
785 "%s: cancel %s scan\n", __func__,
786 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
787 "active" : "passive");
788
789 /* clear bg scan NOPICK and mark cancel request */
790 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
791 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
792 /* force it to fire asap */
793 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
794 0, scan_next, ss);
795 }
796 IEEE80211_UNLOCK(ic);
797}
798
799/*
800 * Public access to scan_next for drivers that manage
801 * scanning themselves (e.g. for firmware-based devices).
802 */
803void
804ieee80211_scan_next(struct ieee80211vap *vap)
805{
806 struct ieee80211com *ic = vap->iv_ic;
807 struct ieee80211_scan_state *ss = ic->ic_scan;
808
809 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss);
810}
811
812/*
813 * Public access to scan_next for drivers that are not able to scan single
814 * channels (e.g. for firmware-based devices).
815 */
816void
817ieee80211_scan_done(struct ieee80211vap *vap)
818{
819 struct ieee80211com *ic = vap->iv_ic;
820 struct ieee80211_scan_state *ss;
821
822 IEEE80211_LOCK(ic);
823 ss = ic->ic_scan;
824 ss->ss_next = ss->ss_last; /* all channels are complete */
825 scan_next(ss);
826 IEEE80211_UNLOCK(ic);
827}
828
829/*
830 * Probe the curent channel, if allowed, while scanning.
831 * If the channel is not marked passive-only then send
832 * a probe request immediately. Otherwise mark state and
833 * listen for beacons on the channel; if we receive something
834 * then we'll transmit a probe request.
835 */
836void
837ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
838{
839 struct ieee80211com *ic = vap->iv_ic;
840 struct ieee80211_scan_state *ss = ic->ic_scan;
841 struct ifnet *ifp = vap->iv_ifp;
842 int i;
843
844 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
845 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
846 return;
847 }
848 /*
849 * Send directed probe requests followed by any
850 * broadcast probe request.
851 * XXX remove dependence on ic/vap->iv_bss
852 */
853 for (i = 0; i < ss->ss_nssid; i++)
854 ieee80211_send_probereq(vap->iv_bss,
855 vap->iv_myaddr, ifp->if_broadcastaddr,
856 ifp->if_broadcastaddr,
857 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len);
858 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0)
859 ieee80211_send_probereq(vap->iv_bss,
860 vap->iv_myaddr, ifp->if_broadcastaddr,
861 ifp->if_broadcastaddr,
862 "", 0);
863}
864
865/*
866 * Scan curchan. If this is an active scan and the channel
867 * is not marked passive then send probe request frame(s).
868 * Arrange for the channel change after maxdwell ticks.
869 */
870static void
871scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
872{
873 struct ieee80211vap *vap = ss->ss_vap;
874
875 IEEE80211_LOCK_ASSERT(vap->iv_ic);
876
877 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
878 ieee80211_probe_curchan(vap, 0);
879 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
880 maxdwell, scan_next, ss);
881}
882
883/*
884 * Handle mindwell requirements completed; initiate a channel
885 * change to the next channel asap.
886 */
887static void
888scan_mindwell(struct ieee80211_scan_state *ss)
889{
890 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss);
891}
892
893/*
894 * Switch to the next channel marked for scanning.
895 */
896static void
897scan_next(void *arg)
898{
899#define ISCAN_REP (ISCAN_MINDWELL | ISCAN_START | ISCAN_DISCARD)
900 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
901 struct ieee80211vap *vap = ss->ss_vap;
902 struct ieee80211com *ic = vap->iv_ic;
903 struct ieee80211_channel *chan;
904 unsigned long maxdwell, scanend;
905 int scandone;
906
907 IEEE80211_LOCK_ASSERT(ic);
908
909 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0)
910 return;
911again:
912 scandone = (ss->ss_next >= ss->ss_last) ||
913 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0;
914 scanend = SCAN_PRIVATE(ss)->ss_scanend;
915 if (!scandone &&
916 (ss->ss_flags & IEEE80211_SCAN_GOTPICK) == 0 &&
917 ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_START) ||
918 time_before(ticks + ss->ss_mindwell, scanend))) {
919 chan = ss->ss_chans[ss->ss_next++];
920
921 /*
922 * Watch for truncation due to the scan end time.
923 */
924 if (time_after(ticks + ss->ss_maxdwell, scanend))
925 maxdwell = scanend - ticks;
926 else
927 maxdwell = ss->ss_maxdwell;
928
929 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
930 "%s: chan %3d%c -> %3d%c [%s, dwell min %lu max %lu]\n",
931 __func__,
932 ieee80211_chan2ieee(ic, ic->ic_curchan),
933 channel_type(ic->ic_curchan),
934 ieee80211_chan2ieee(ic, chan), channel_type(chan),
935 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
936 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
937 "active" : "passive",
938 ss->ss_mindwell, maxdwell);
939
940 /*
941 * Potentially change channel and phy mode.
942 */
943 change_channel(ic, chan);
944
945 /*
946 * Scan curchan. Drivers for "intelligent hardware"
947 * override ic_scan_curchan to tell the device to do
948 * the work. Otherwise we manage the work outselves;
949 * sending a probe request (as needed), and arming the
950 * timeout to switch channels after maxdwell ticks.
951 */
952 ic->ic_scan_curchan(ss, maxdwell);
953
954 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell;
955 /* clear mindwell lock and initial channel change flush */
956 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
957 } else {
958 ic->ic_scan_end(ic); /* notify driver */
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_setcurchan(ic, ic->ic_bsschan);
970 /* clear internal flags and any indication of a pick */
971 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
972 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK;
973
974 /*
975 * If not canceled and scan completed, do post-processing.
976 * If the callback function returns 0, then it wants to
977 * continue/restart scanning. Unfortunately we needed to
978 * notify the driver to end the scan above to avoid having
979 * rx frames alter the scan candidate list.
980 */
981 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 &&
982 !ss->ss_ops->scan_end(ss, vap) &&
983 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 &&
984 time_before(ticks + ss->ss_mindwell, scanend)) {
985 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
986 "%s: done, restart "
987 "[ticks %u, dwell min %lu scanend %lu]\n",
988 __func__,
989 ticks, ss->ss_mindwell, scanend);
990 ss->ss_next = 0; /* reset to begining */
991 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
992 vap->iv_stats.is_scan_active++;
993 else
994 vap->iv_stats.is_scan_passive++;
995
996 ss->ss_ops->scan_restart(ss, vap); /* XXX? */
997 ic->ic_scan_start(ic); /* notify driver */
998 goto again;
999 } else {
1000 /* past here, scandone is ``true'' if not in bg mode */
1001 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0)
1002 scandone = 1;
1003
1004 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1005 "%s: %s, "
1006 "[ticks %u, dwell min %lu scanend %lu]\n",
1007 __func__, scandone ? "done" : "stopped",
1008 ticks, ss->ss_mindwell, scanend);
1009
1010 /*
1011 * Clear the SCAN bit first in case frames are
1012 * pending on the station power save queue. If
1013 * we defer this then the dispatch of the frames
1014 * may generate a request to cancel scanning.
1015 */
1016 ic->ic_flags &= ~IEEE80211_F_SCAN;
1017 /*
1018 * Drop out of power save mode when a scan has
1019 * completed. If this scan was prematurely terminated
1020 * because it is a background scan then don't notify
1021 * the ap; we'll either return to scanning after we
1022 * receive the beacon frame or we'll drop out of power
1023 * save mode because the beacon indicates we have frames
1024 * waiting for us.
1025 */
1026 if (scandone) {
1027 ieee80211_sta_pwrsave(vap, 0);
1028 if (ss->ss_next >= ss->ss_last) {
1029 ieee80211_notify_scan_done(vap);
1030 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN;
1031 }
1032 }
1033 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_CANCEL;
1034 ss->ss_flags &=
1035 ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST);
1036 }
1037 }
1038#undef ISCAN_REP
1039}
1040
1041#ifdef IEEE80211_DEBUG
1042static void
1043dump_country(const uint8_t *ie)
1044{
1045 const struct ieee80211_country_ie *cie =
1046 (const struct ieee80211_country_ie *) ie;
1047 int i, nbands, schan, nchan;
1048
1049 if (cie->len < 3) {
1050 printf(" <bogus country ie, len %d>", cie->len);
1051 return;
1052 }
1053 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
1054 nbands = (cie->len - 3) / sizeof(cie->band[0]);
1055 for (i = 0; i < nbands; i++) {
1056 schan = cie->band[i].schan;
1057 nchan = cie->band[i].nchan;
1058 if (nchan != 1)
1059 printf(" %u-%u,%u", schan, schan + nchan-1,
1060 cie->band[i].maxtxpwr);
1061 else
1062 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
1063 }
1064 printf("]");
1065}
1066
1067static void
1068dump_probe_beacon(uint8_t subtype, int isnew,
1069 const uint8_t mac[IEEE80211_ADDR_LEN],
1070 const struct ieee80211_scanparams *sp, int rssi)
1071{
1072
1073 printf("[%s] %s%s on chan %u (bss chan %u) ",
1074 ether_sprintf(mac), isnew ? "new " : "",
1075 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1076 sp->chan, sp->bchan);
1077 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1078 printf(" rssi %d\n", rssi);
1079
1080 if (isnew) {
1081 printf("[%s] caps 0x%x bintval %u erp 0x%x",
1082 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1083 if (sp->country != NULL)
1084 dump_country(sp->country);
1085 printf("\n");
1086 }
1087}
1088#endif /* IEEE80211_DEBUG */
1089
1090/*
1091 * Process a beacon or probe response frame.
1092 */
1093void
1094ieee80211_add_scan(struct ieee80211vap *vap,
1095 const struct ieee80211_scanparams *sp,
1096 const struct ieee80211_frame *wh,
1097 int subtype, int rssi, int noise, int rstamp)
1098{
1099 struct ieee80211com *ic = vap->iv_ic;
1100 struct ieee80211_scan_state *ss = ic->ic_scan;
1101
1102 /* XXX locking */
1103 /*
1104 * Frames received during startup are discarded to avoid
1105 * using scan state setup on the initial entry to the timer
1106 * callback. This can occur because the device may enable
1107 * rx prior to our doing the initial channel change in the
1108 * timer routine.
1109 */
1110 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD)
1111 return;
1112#ifdef IEEE80211_DEBUG
1113 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN))
1114 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi);
1115#endif
1116 if (ss->ss_ops != NULL &&
1117 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise, rstamp)) {
1118 /*
1119 * If we've reached the min dwell time terminate
1120 * the timer so we'll switch to the next channel.
1121 */
1122 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 &&
1123 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) {
1124 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1125 "%s: chan %3d%c min dwell met (%u > %lu)\n",
1126 __func__,
1127 ieee80211_chan2ieee(ic, ic->ic_curchan),
1128 channel_type(ic->ic_curchan),
1129 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell);
1130 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL;
1131 /*
1132 * NB: trigger at next clock tick or wait for the
1133 * hardware.
1134 */
1135 ic->ic_scan_mindwell(ss);
1136 }
1137 }
1138}
1139
1140/*
1141 * Timeout/age scan cache entries; called from sta timeout
1142 * timer (XXX should be self-contained).
1143 */
1144void
1145ieee80211_scan_timeout(struct ieee80211com *ic)
1146{
1147 struct ieee80211_scan_state *ss = ic->ic_scan;
1148
1149 if (ss->ss_ops != NULL)
1150 ss->ss_ops->scan_age(ss);
1151}
1152
1153/*
1154 * Mark a scan cache entry after a successful associate.
1155 */
1156void
1157ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
1158{
1159 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1160
1161 if (ss->ss_ops != NULL) {
1162 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
1163 mac, "%s", __func__);
1164 ss->ss_ops->scan_assoc_success(ss, mac);
1165 }
1166}
1167
1168/*
1169 * Demerit a scan cache entry after failing to associate.
1170 */
1171void
1172ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
1173 const uint8_t mac[], int reason)
1174{
1175 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1176
1177 if (ss->ss_ops != NULL) {
1178 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
1179 "%s: reason %u", __func__, reason);
1180 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
1181 }
1182}
1183
1184/*
1185 * Iterate over the contents of the scan cache.
1186 */
1187void
1188ieee80211_scan_iterate(struct ieee80211vap *vap,
1189 ieee80211_scan_iter_func *f, void *arg)
1190{
1191 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1192
1193 if (ss->ss_ops != NULL)
1194 ss->ss_ops->scan_iterate(ss, f, arg);
1195}
1196
1197/*
1198 * Flush the contents of the scan cache.
1199 */
1200void
1201ieee80211_scan_flush(struct ieee80211vap *vap)
1202{
1203 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1204
1205 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
1206 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
1207 ss->ss_ops->scan_flush(ss);
1208 }
1209}
1210
1211/*
1212 * Check the scan cache for an ap/channel to use; if that
1213 * fails then kick off a new scan.
1214 */
1215struct ieee80211_channel *
1216ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
1217{
1218 struct ieee80211_scan_state *ss = ic->ic_scan;
1219
1220 IEEE80211_LOCK_ASSERT(ic);
1221
1222 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
1223 /* XXX printf? */
1224 return NULL;
1225 }
1226 if (ss->ss_ops->scan_pickchan == NULL) {
1227 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
1228 "%s: scan module does not support picking a channel, "
1229 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
1230 return NULL;
1231 }
1232 return ss->ss_ops->scan_pickchan(ss, flags);
1233}