1 /*-
2 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28
29 /*
30 * IEEE 802.11 scanning support.
31 */
32 #include "opt_wlan.h"
33
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/proc.h>
37 #include <sys/kernel.h>
38 #include <sys/condvar.h>
39
40 #include <sys/socket.h>
41
42 #include <net/if.h>
43 #include <net/if_media.h>
44 #include <net/ethernet.h>
45
46 #include <net80211/ieee80211_var.h>
47
48 #include <net/bpf.h>
49
50 struct scan_state {
51 struct ieee80211_scan_state base; /* public state */
52
53 u_int ss_iflags; /* flags used internally */
54 #define ISCAN_MINDWELL 0x0001 /* min dwell time reached */
55 #define ISCAN_DISCARD 0x0002 /* discard rx'd frames */
56 #define ISCAN_CANCEL 0x0004 /* cancel current scan */
57 #define ISCAN_ABORT 0x0008 /* end the scan immediately */
58 unsigned long ss_chanmindwell; /* min dwell on curchan */
59 unsigned long ss_scanend; /* time scan must stop */
60 u_int ss_duration; /* duration for next scan */
61 struct task ss_scan_task; /* scan execution */
62 struct cv ss_scan_cv; /* scan signal */
63 struct callout ss_scan_timer; /* scan timer */
64 };
65 #define SCAN_PRIVATE(ss) ((struct scan_state *) ss)
66
67 /*
68 * Amount of time to go off-channel during a background
69 * scan. This value should be large enough to catch most
70 * ap's but short enough that we can return on-channel
71 * before our listen interval expires.
72 *
73 * XXX tunable
74 * XXX check against configured listen interval
75 */
76 #define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150)
77
78 /*
79 * Roaming-related defaults. RSSI thresholds are as returned by the
80 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
81 * .5M units) or MCS.
82 */
83 /* rssi thresholds */
84 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
85 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
86 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
87 /* transmit rate thresholds */
88 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
89 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
90 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
91 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
92 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
93 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
94
95 static void scan_curchan(struct ieee80211_scan_state *, unsigned long);
96 static void scan_mindwell(struct ieee80211_scan_state *);
97 static void scan_signal(void *);
98 static void scan_task(void *, int);
99
100 MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state");
101
102 void
ieee80211_scan_attach(struct ieee80211com * ic)103 ieee80211_scan_attach(struct ieee80211com *ic)
104 {
105 struct scan_state *ss;
106
107 ss = (struct scan_state *) malloc(sizeof(struct scan_state),
108 M_80211_SCAN, M_NOWAIT | M_ZERO);
109 if (ss == NULL) {
110 ic->ic_scan = NULL;
111 return;
112 }
113 callout_init_mtx(&ss->ss_scan_timer, IEEE80211_LOCK_OBJ(ic), 0);
114 cv_init(&ss->ss_scan_cv, "scan");
115 TASK_INIT(&ss->ss_scan_task, 0, scan_task, ss);
116 ic->ic_scan = &ss->base;
117 ss->base.ss_ic = ic;
118
119 ic->ic_scan_curchan = scan_curchan;
120 ic->ic_scan_mindwell = scan_mindwell;
121 }
122
123 void
ieee80211_scan_detach(struct ieee80211com * ic)124 ieee80211_scan_detach(struct ieee80211com *ic)
125 {
126 struct ieee80211_scan_state *ss = ic->ic_scan;
127
128 if (ss != NULL) {
129 IEEE80211_LOCK(ic);
130 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT;
131 scan_signal(ss);
132 IEEE80211_UNLOCK(ic);
133 ieee80211_draintask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
134 callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer);
135 KASSERT((ic->ic_flags & IEEE80211_F_SCAN) == 0,
136 ("scan still running"));
137 if (ss->ss_ops != NULL) {
138 ss->ss_ops->scan_detach(ss);
139 ss->ss_ops = NULL;
140 }
141 ic->ic_scan = NULL;
142 free(SCAN_PRIVATE(ss), M_80211_SCAN);
143 }
144 }
145
146 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
147 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
148 .rate = ROAM_RATE_11A_DEFAULT },
149 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
150 .rate = ROAM_RATE_11B_DEFAULT },
151 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
152 .rate = ROAM_RATE_11BONLY_DEFAULT },
153 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
154 .rate = ROAM_RATE_11A_DEFAULT },
155 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
156 .rate = ROAM_RATE_11A_DEFAULT },
157 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
158 .rate = ROAM_RATE_11A_DEFAULT },
159 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
160 .rate = ROAM_RATE_HALF_DEFAULT },
161 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
162 .rate = ROAM_RATE_QUARTER_DEFAULT },
163 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
164 .rate = ROAM_MCS_11N_DEFAULT },
165 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
166 .rate = ROAM_MCS_11N_DEFAULT },
167 };
168
169 void
ieee80211_scan_vattach(struct ieee80211vap * vap)170 ieee80211_scan_vattach(struct ieee80211vap *vap)
171 {
172 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
173 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
174 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
175
176 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
177 memcpy(vap->iv_roamparms, defroam, sizeof(defroam));
178 }
179
180 void
ieee80211_scan_vdetach(struct ieee80211vap * vap)181 ieee80211_scan_vdetach(struct ieee80211vap *vap)
182 {
183 struct ieee80211com *ic = vap->iv_ic;
184 struct ieee80211_scan_state *ss;
185
186 IEEE80211_LOCK(ic);
187 ss = ic->ic_scan;
188 if (ss != NULL && ss->ss_vap == vap) {
189 if (ic->ic_flags & IEEE80211_F_SCAN) {
190 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT;
191 scan_signal(ss);
192 }
193 if (ss->ss_ops != NULL) {
194 ss->ss_ops->scan_detach(ss);
195 ss->ss_ops = NULL;
196 }
197 ss->ss_vap = NULL;
198 }
199 IEEE80211_UNLOCK(ic);
200 }
201
202 /*
203 * Simple-minded scanner module support.
204 */
205 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
206 "wlan_scan_sta", /* IEEE80211_M_IBSS */
207 "wlan_scan_sta", /* IEEE80211_M_STA */
208 "wlan_scan_wds", /* IEEE80211_M_WDS */
209 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
210 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
211 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
212 "wlan_scan_sta", /* IEEE80211_M_MBSS */
213 };
214 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
215
216 const struct ieee80211_scanner *
ieee80211_scanner_get(enum ieee80211_opmode mode)217 ieee80211_scanner_get(enum ieee80211_opmode mode)
218 {
219 if (mode >= IEEE80211_OPMODE_MAX)
220 return NULL;
221 if (scanners[mode] == NULL)
222 ieee80211_load_module(scan_modnames[mode]);
223 return scanners[mode];
224 }
225
226 void
ieee80211_scanner_register(enum ieee80211_opmode mode,const struct ieee80211_scanner * scan)227 ieee80211_scanner_register(enum ieee80211_opmode mode,
228 const struct ieee80211_scanner *scan)
229 {
230 if (mode >= IEEE80211_OPMODE_MAX)
231 return;
232 scanners[mode] = scan;
233 }
234
235 void
ieee80211_scanner_unregister(enum ieee80211_opmode mode,const struct ieee80211_scanner * scan)236 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
237 const struct ieee80211_scanner *scan)
238 {
239 if (mode >= IEEE80211_OPMODE_MAX)
240 return;
241 if (scanners[mode] == scan)
242 scanners[mode] = NULL;
243 }
244
245 void
ieee80211_scanner_unregister_all(const struct ieee80211_scanner * scan)246 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
247 {
248 int m;
249
250 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
251 if (scanners[m] == scan)
252 scanners[m] = NULL;
253 }
254
255 /*
256 * Update common scanner state to reflect the current
257 * operating mode. This is called when the state machine
258 * is transitioned to RUN state w/o scanning--e.g. when
259 * operating in monitor mode. The purpose of this is to
260 * ensure later callbacks find ss_ops set to properly
261 * reflect current operating mode.
262 */
263 static void
scan_update_locked(struct ieee80211vap * vap,const struct ieee80211_scanner * scan)264 scan_update_locked(struct ieee80211vap *vap,
265 const struct ieee80211_scanner *scan)
266 {
267 struct ieee80211com *ic = vap->iv_ic;
268 struct ieee80211_scan_state *ss = ic->ic_scan;
269
270 IEEE80211_LOCK_ASSERT(ic);
271
272 #ifdef IEEE80211_DEBUG
273 if (ss->ss_vap != vap || ss->ss_ops != scan) {
274 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
275 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
276 __func__,
277 ss->ss_vap != NULL ?
278 ss->ss_vap->iv_ifp->if_xname : "none",
279 ss->ss_vap != NULL ?
280 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
281 vap->iv_ifp->if_xname,
282 ieee80211_opmode_name[vap->iv_opmode]);
283 }
284 #endif
285 ss->ss_vap = vap;
286 if (ss->ss_ops != scan) {
287 /*
288 * Switch scanners; detach old, attach new. Special
289 * case where a single scan module implements multiple
290 * policies by using different scan ops but a common
291 * core. We assume if the old and new attach methods
292 * are identical then it's ok to just change ss_ops
293 * and not flush the internal state of the module.
294 */
295 if (scan == NULL || ss->ss_ops == NULL ||
296 ss->ss_ops->scan_attach != scan->scan_attach) {
297 if (ss->ss_ops != NULL)
298 ss->ss_ops->scan_detach(ss);
299 if (scan != NULL && !scan->scan_attach(ss)) {
300 /* XXX attach failure */
301 /* XXX stat+msg */
302 scan = NULL;
303 }
304 }
305 ss->ss_ops = scan;
306 }
307 }
308
309 static char
channel_type(const struct ieee80211_channel * c)310 channel_type(const struct ieee80211_channel *c)
311 {
312 if (IEEE80211_IS_CHAN_ST(c))
313 return 'S';
314 if (IEEE80211_IS_CHAN_108A(c))
315 return 'T';
316 if (IEEE80211_IS_CHAN_108G(c))
317 return 'G';
318 if (IEEE80211_IS_CHAN_HT(c))
319 return 'n';
320 if (IEEE80211_IS_CHAN_A(c))
321 return 'a';
322 if (IEEE80211_IS_CHAN_ANYG(c))
323 return 'g';
324 if (IEEE80211_IS_CHAN_B(c))
325 return 'b';
326 return 'f';
327 }
328
329 void
ieee80211_scan_dump_channels(const struct ieee80211_scan_state * ss)330 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
331 {
332 struct ieee80211com *ic = ss->ss_ic;
333 const char *sep;
334 int i;
335
336 sep = "";
337 for (i = ss->ss_next; i < ss->ss_last; i++) {
338 const struct ieee80211_channel *c = ss->ss_chans[i];
339
340 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
341 channel_type(c));
342 sep = ", ";
343 }
344 }
345
346 #ifdef IEEE80211_DEBUG
347 static void
scan_dump(struct ieee80211_scan_state * ss)348 scan_dump(struct ieee80211_scan_state *ss)
349 {
350 struct ieee80211vap *vap = ss->ss_vap;
351
352 if_printf(vap->iv_ifp, "scan set ");
353 ieee80211_scan_dump_channels(ss);
354 printf(" dwell min %lums max %lums\n",
355 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
356 }
357 #endif /* IEEE80211_DEBUG */
358
359 static void
copy_ssid(struct ieee80211vap * vap,struct ieee80211_scan_state * ss,int nssid,const struct ieee80211_scan_ssid ssids[])360 copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
361 int nssid, const struct ieee80211_scan_ssid ssids[])
362 {
363 if (nssid > IEEE80211_SCAN_MAX_SSID) {
364 /* XXX printf */
365 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
366 "%s: too many ssid %d, ignoring all of them\n",
367 __func__, nssid);
368 return;
369 }
370 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
371 ss->ss_nssid = nssid;
372 }
373
374 /*
375 * Start a scan unless one is already going.
376 */
377 static int
start_scan_locked(const struct ieee80211_scanner * scan,struct ieee80211vap * vap,int flags,u_int duration,u_int mindwell,u_int maxdwell,u_int nssid,const struct ieee80211_scan_ssid ssids[])378 start_scan_locked(const struct ieee80211_scanner *scan,
379 struct ieee80211vap *vap, int flags, u_int duration,
380 u_int mindwell, u_int maxdwell,
381 u_int nssid, const struct ieee80211_scan_ssid ssids[])
382 {
383 struct ieee80211com *ic = vap->iv_ic;
384 struct ieee80211_scan_state *ss = ic->ic_scan;
385
386 IEEE80211_LOCK_ASSERT(ic);
387
388 if (ic->ic_flags & IEEE80211_F_CSAPENDING) {
389 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
390 "%s: scan inhibited by pending channel change\n", __func__);
391 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
392 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
393 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n"
394 , __func__
395 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
396 , duration, mindwell, maxdwell
397 , ieee80211_phymode_name[vap->iv_des_mode]
398 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
399 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
400 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
401 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : ""
402 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
403 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
404 );
405
406 scan_update_locked(vap, scan);
407 if (ss->ss_ops != NULL) {
408 if ((flags & IEEE80211_SCAN_NOSSID) == 0)
409 copy_ssid(vap, ss, nssid, ssids);
410
411 /* NB: top 4 bits for internal use */
412 ss->ss_flags = flags & 0xfff;
413 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
414 vap->iv_stats.is_scan_active++;
415 else
416 vap->iv_stats.is_scan_passive++;
417 if (flags & IEEE80211_SCAN_FLUSH)
418 ss->ss_ops->scan_flush(ss);
419 if (flags & IEEE80211_SCAN_BGSCAN)
420 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN;
421
422 /* NB: flush frames rx'd before 1st channel change */
423 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
424 SCAN_PRIVATE(ss)->ss_duration = duration;
425 ss->ss_next = 0;
426 ss->ss_mindwell = mindwell;
427 ss->ss_maxdwell = maxdwell;
428 /* NB: scan_start must be before the scan runtask */
429 ss->ss_ops->scan_start(ss, vap);
430 #ifdef IEEE80211_DEBUG
431 if (ieee80211_msg_scan(vap))
432 scan_dump(ss);
433 #endif /* IEEE80211_DEBUG */
434 ic->ic_flags |= IEEE80211_F_SCAN;
435 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
436 }
437 return 1;
438 } else {
439 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
440 "%s: %s scan already in progress\n", __func__,
441 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
442 }
443 return 0;
444 }
445
446 /*
447 * Start a scan unless one is already going.
448 */
449 int
ieee80211_start_scan(struct ieee80211vap * vap,int flags,u_int duration,u_int mindwell,u_int maxdwell,u_int nssid,const struct ieee80211_scan_ssid ssids[])450 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
451 u_int duration, u_int mindwell, u_int maxdwell,
452 u_int nssid, const struct ieee80211_scan_ssid ssids[])
453 {
454 struct ieee80211com *ic = vap->iv_ic;
455 const struct ieee80211_scanner *scan;
456 int result;
457
458 scan = ieee80211_scanner_get(vap->iv_opmode);
459 if (scan == NULL) {
460 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
461 "%s: no scanner support for %s mode\n",
462 __func__, ieee80211_opmode_name[vap->iv_opmode]);
463 /* XXX stat */
464 return 0;
465 }
466
467 IEEE80211_LOCK(ic);
468 result = start_scan_locked(scan, vap, flags, duration,
469 mindwell, maxdwell, nssid, ssids);
470 IEEE80211_UNLOCK(ic);
471
472 return result;
473 }
474
475 /*
476 * Check the scan cache for an ap/channel to use; if that
477 * fails then kick off a new scan.
478 */
479 int
ieee80211_check_scan(struct ieee80211vap * vap,int flags,u_int duration,u_int mindwell,u_int maxdwell,u_int nssid,const struct ieee80211_scan_ssid ssids[])480 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
481 u_int duration, u_int mindwell, u_int maxdwell,
482 u_int nssid, const struct ieee80211_scan_ssid ssids[])
483 {
484 struct ieee80211com *ic = vap->iv_ic;
485 struct ieee80211_scan_state *ss = ic->ic_scan;
486 const struct ieee80211_scanner *scan;
487 int result;
488
489 scan = ieee80211_scanner_get(vap->iv_opmode);
490 if (scan == NULL) {
491 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
492 "%s: no scanner support for %s mode\n",
493 __func__, vap->iv_opmode);
494 /* XXX stat */
495 return 0;
496 }
497
498 /*
499 * Check if there's a list of scan candidates already.
500 * XXX want more than the ap we're currently associated with
501 */
502
503 IEEE80211_LOCK(ic);
504 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
505 "%s: %s scan, %s%s%s%s%s\n"
506 , __func__
507 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
508 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
509 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
510 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
511 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
512 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
513 );
514
515 if (ss->ss_ops != scan) {
516 /* XXX re-use cache contents? e.g. adhoc<->sta */
517 flags |= IEEE80211_SCAN_FLUSH;
518 }
519 scan_update_locked(vap, scan);
520 if (ss->ss_ops != NULL) {
521 /* XXX verify ss_ops matches vap->iv_opmode */
522 if ((flags & IEEE80211_SCAN_NOSSID) == 0) {
523 /*
524 * Update the ssid list and mark flags so if
525 * we call start_scan it doesn't duplicate work.
526 */
527 copy_ssid(vap, ss, nssid, ssids);
528 flags |= IEEE80211_SCAN_NOSSID;
529 }
530 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 &&
531 (flags & IEEE80211_SCAN_FLUSH) == 0 &&
532 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
533 /*
534 * We're not currently scanning and the cache is
535 * deemed hot enough to consult. Lock out others
536 * by marking IEEE80211_F_SCAN while we decide if
537 * something is already in the scan cache we can
538 * use. Also discard any frames that might come
539 * in while temporarily marked as scanning.
540 */
541 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
542 ic->ic_flags |= IEEE80211_F_SCAN;
543
544 /* NB: need to use supplied flags in check */
545 ss->ss_flags = flags & 0xff;
546 result = ss->ss_ops->scan_end(ss, vap);
547
548 ic->ic_flags &= ~IEEE80211_F_SCAN;
549 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD;
550 if (result) {
551 ieee80211_notify_scan_done(vap);
552 IEEE80211_UNLOCK(ic);
553 return 1;
554 }
555 }
556 }
557 result = start_scan_locked(scan, vap, flags, duration,
558 mindwell, maxdwell, nssid, ssids);
559 IEEE80211_UNLOCK(ic);
560
561 return result;
562 }
563
564 /*
565 * Check the scan cache for an ap/channel to use; if that fails
566 * then kick off a scan using the current settings.
567 */
568 int
ieee80211_check_scan_current(struct ieee80211vap * vap)569 ieee80211_check_scan_current(struct ieee80211vap *vap)
570 {
571 return ieee80211_check_scan(vap,
572 IEEE80211_SCAN_ACTIVE,
573 IEEE80211_SCAN_FOREVER, 0, 0,
574 vap->iv_des_nssid, vap->iv_des_ssid);
575 }
576
577 /*
578 * Restart a previous scan. If the previous scan completed
579 * then we start again using the existing channel list.
580 */
581 int
ieee80211_bg_scan(struct ieee80211vap * vap,int flags)582 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
583 {
584 struct ieee80211com *ic = vap->iv_ic;
585 struct ieee80211_scan_state *ss = ic->ic_scan;
586 const struct ieee80211_scanner *scan;
587
588 scan = ieee80211_scanner_get(vap->iv_opmode);
589 if (scan == NULL) {
590 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
591 "%s: no scanner support for %s mode\n",
592 __func__, vap->iv_opmode);
593 /* XXX stat */
594 return 0;
595 }
596
597 IEEE80211_LOCK(ic);
598 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
599 u_int duration;
600 /*
601 * Go off-channel for a fixed interval that is large
602 * enough to catch most ap's but short enough that
603 * we can return on-channel before our listen interval
604 * expires.
605 */
606 duration = IEEE80211_SCAN_OFFCHANNEL;
607
608 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
609 "%s: %s scan, ticks %u duration %lu\n", __func__,
610 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive",
611 ticks, duration);
612
613 scan_update_locked(vap, scan);
614 if (ss->ss_ops != NULL) {
615 ss->ss_vap = vap;
616 /*
617 * A background scan does not select a new sta; it
618 * just refreshes the scan cache. Also, indicate
619 * the scan logic should follow the beacon schedule:
620 * we go off-channel and scan for a while, then
621 * return to the bss channel to receive a beacon,
622 * then go off-channel again. All during this time
623 * we notify the ap we're in power save mode. When
624 * the scan is complete we leave power save mode.
625 * If any beacon indicates there are frames pending
626 * for us then we drop out of power save mode
627 * (and background scan) automatically by way of the
628 * usual sta power save logic.
629 */
630 ss->ss_flags |= IEEE80211_SCAN_NOPICK
631 | IEEE80211_SCAN_BGSCAN
632 | flags
633 ;
634 /* if previous scan completed, restart */
635 if (ss->ss_next >= ss->ss_last) {
636 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
637 vap->iv_stats.is_scan_active++;
638 else
639 vap->iv_stats.is_scan_passive++;
640 /*
641 * NB: beware of the scan cache being flushed;
642 * if the channel list is empty use the
643 * scan_start method to populate it.
644 */
645 ss->ss_next = 0;
646 if (ss->ss_last != 0)
647 ss->ss_ops->scan_restart(ss, vap);
648 else {
649 ss->ss_ops->scan_start(ss, vap);
650 #ifdef IEEE80211_DEBUG
651 if (ieee80211_msg_scan(vap))
652 scan_dump(ss);
653 #endif /* IEEE80211_DEBUG */
654 }
655 }
656 /* NB: flush frames rx'd before 1st channel change */
657 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD;
658 SCAN_PRIVATE(ss)->ss_duration = duration;
659 ss->ss_maxdwell = duration;
660 ic->ic_flags |= IEEE80211_F_SCAN;
661 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN;
662 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
663 } else {
664 /* XXX msg+stat */
665 }
666 } else {
667 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
668 "%s: %s scan already in progress\n", __func__,
669 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive");
670 }
671 IEEE80211_UNLOCK(ic);
672
673 /* NB: racey, does it matter? */
674 return (ic->ic_flags & IEEE80211_F_SCAN);
675 }
676
677 /*
678 * Cancel any scan currently going on for the specified vap.
679 */
680 void
ieee80211_cancel_scan(struct ieee80211vap * vap)681 ieee80211_cancel_scan(struct ieee80211vap *vap)
682 {
683 struct ieee80211com *ic = vap->iv_ic;
684 struct ieee80211_scan_state *ss = ic->ic_scan;
685
686 IEEE80211_LOCK(ic);
687 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
688 ss->ss_vap == vap &&
689 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
690 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
691 "%s: cancel %s scan\n", __func__,
692 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
693 "active" : "passive");
694
695 /* clear bg scan NOPICK and mark cancel request */
696 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
697 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
698 /* wake up the scan task */
699 scan_signal(ss);
700 }
701 IEEE80211_UNLOCK(ic);
702 }
703
704 /*
705 * Cancel any scan currently going on.
706 */
707 void
ieee80211_cancel_anyscan(struct ieee80211vap * vap)708 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
709 {
710 struct ieee80211com *ic = vap->iv_ic;
711 struct ieee80211_scan_state *ss = ic->ic_scan;
712
713 IEEE80211_LOCK(ic);
714 if ((ic->ic_flags & IEEE80211_F_SCAN) &&
715 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) {
716 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
717 "%s: cancel %s scan\n", __func__,
718 ss->ss_flags & IEEE80211_SCAN_ACTIVE ?
719 "active" : "passive");
720
721 /* clear bg scan NOPICK and mark cancel request */
722 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
723 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL;
724 /* wake up the scan task */
725 scan_signal(ss);
726 }
727 IEEE80211_UNLOCK(ic);
728 }
729
730 /*
731 * Public access to scan_next for drivers that manage
732 * scanning themselves (e.g. for firmware-based devices).
733 */
734 void
ieee80211_scan_next(struct ieee80211vap * vap)735 ieee80211_scan_next(struct ieee80211vap *vap)
736 {
737 struct ieee80211com *ic = vap->iv_ic;
738 struct ieee80211_scan_state *ss = ic->ic_scan;
739
740 /* wake up the scan task */
741 IEEE80211_LOCK(ic);
742 scan_signal(ss);
743 IEEE80211_UNLOCK(ic);
744 }
745
746 /*
747 * Public access to scan_next for drivers that are not able to scan single
748 * channels (e.g. for firmware-based devices).
749 */
750 void
ieee80211_scan_done(struct ieee80211vap * vap)751 ieee80211_scan_done(struct ieee80211vap *vap)
752 {
753 struct ieee80211com *ic = vap->iv_ic;
754 struct ieee80211_scan_state *ss;
755
756 IEEE80211_LOCK(ic);
757 ss = ic->ic_scan;
758 ss->ss_next = ss->ss_last; /* all channels are complete */
759 scan_signal(ss);
760 IEEE80211_UNLOCK(ic);
761 }
762
763 /*
764 * Probe the curent channel, if allowed, while scanning.
765 * If the channel is not marked passive-only then send
766 * a probe request immediately. Otherwise mark state and
767 * listen for beacons on the channel; if we receive something
768 * then we'll transmit a probe request.
769 */
770 void
ieee80211_probe_curchan(struct ieee80211vap * vap,int force)771 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
772 {
773 struct ieee80211com *ic = vap->iv_ic;
774 struct ieee80211_scan_state *ss = ic->ic_scan;
775 struct ifnet *ifp = vap->iv_ifp;
776 int i;
777
778 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
779 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
780 return;
781 }
782 /*
783 * Send directed probe requests followed by any
784 * broadcast probe request.
785 * XXX remove dependence on ic/vap->iv_bss
786 */
787 for (i = 0; i < ss->ss_nssid; i++)
788 ieee80211_send_probereq(vap->iv_bss,
789 vap->iv_myaddr, ifp->if_broadcastaddr,
790 ifp->if_broadcastaddr,
791 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len);
792 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0)
793 ieee80211_send_probereq(vap->iv_bss,
794 vap->iv_myaddr, ifp->if_broadcastaddr,
795 ifp->if_broadcastaddr,
796 "", 0);
797 }
798
799 /*
800 * Scan curchan. If this is an active scan and the channel
801 * is not marked passive then send probe request frame(s).
802 * Arrange for the channel change after maxdwell ticks.
803 */
804 static void
scan_curchan(struct ieee80211_scan_state * ss,unsigned long maxdwell)805 scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell)
806 {
807 struct ieee80211vap *vap = ss->ss_vap;
808
809 IEEE80211_LOCK(vap->iv_ic);
810 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
811 ieee80211_probe_curchan(vap, 0);
812 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer,
813 maxdwell, scan_signal, ss);
814 IEEE80211_UNLOCK(vap->iv_ic);
815 }
816
817 static void
scan_signal(void * arg)818 scan_signal(void *arg)
819 {
820 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
821
822 IEEE80211_LOCK_ASSERT(ss->ss_ic);
823
824 cv_signal(&SCAN_PRIVATE(ss)->ss_scan_cv);
825 }
826
827 /*
828 * Handle mindwell requirements completed; initiate a channel
829 * change to the next channel asap.
830 */
831 static void
scan_mindwell(struct ieee80211_scan_state * ss)832 scan_mindwell(struct ieee80211_scan_state *ss)
833 {
834 struct ieee80211com *ic = ss->ss_ic;
835
836 IEEE80211_LOCK(ic);
837 scan_signal(ss);
838 IEEE80211_UNLOCK(ic);
839 }
840
841 static void
scan_task(void * arg,int pending)842 scan_task(void *arg, int pending)
843 {
844 #define ISCAN_REP (ISCAN_MINDWELL | ISCAN_DISCARD)
845 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg;
846 struct ieee80211vap *vap = ss->ss_vap;
847 struct ieee80211com *ic = ss->ss_ic;
848 struct ieee80211_channel *chan;
849 unsigned long maxdwell, scanend;
850 int scandone = 0;
851
852 IEEE80211_LOCK(ic);
853 if (vap == NULL || (ic->ic_flags & IEEE80211_F_SCAN) == 0 ||
854 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)) {
855 /* Cancelled before we started */
856 goto done;
857 }
858
859 if (ss->ss_next == ss->ss_last) {
860 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
861 "%s: no channels to scan\n", __func__);
862 scandone = 1;
863 goto done;
864 }
865
866 if (vap->iv_opmode == IEEE80211_M_STA &&
867 vap->iv_state == IEEE80211_S_RUN) {
868 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) {
869 /* Enable station power save mode */
870 vap->iv_sta_ps(vap, 1);
871 /*
872 * Use an 1ms delay so the null data frame has a chance
873 * to go out.
874 * XXX Should use M_TXCB mechanism to eliminate this.
875 */
876 cv_timedwait(&SCAN_PRIVATE(ss)->ss_scan_cv,
877 IEEE80211_LOCK_OBJ(ic), hz / 1000);
878 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
879 goto done;
880 }
881 }
882
883 scanend = ticks + SCAN_PRIVATE(ss)->ss_duration;
884 IEEE80211_UNLOCK(ic);
885 ic->ic_scan_start(ic); /* notify driver */
886 IEEE80211_LOCK(ic);
887
888 for (;;) {
889 scandone = (ss->ss_next >= ss->ss_last) ||
890 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0;
891 if (scandone || (ss->ss_flags & IEEE80211_SCAN_GOTPICK) ||
892 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) ||
893 time_after(ticks + ss->ss_mindwell, scanend))
894 break;
895
896 chan = ss->ss_chans[ss->ss_next++];
897
898 /*
899 * Watch for truncation due to the scan end time.
900 */
901 if (time_after(ticks + ss->ss_maxdwell, scanend))
902 maxdwell = scanend - ticks;
903 else
904 maxdwell = ss->ss_maxdwell;
905
906 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
907 "%s: chan %3d%c -> %3d%c [%s, dwell min %lums max %lums]\n",
908 __func__,
909 ieee80211_chan2ieee(ic, ic->ic_curchan),
910 channel_type(ic->ic_curchan),
911 ieee80211_chan2ieee(ic, chan), channel_type(chan),
912 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) &&
913 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ?
914 "active" : "passive",
915 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(maxdwell));
916
917 /*
918 * Potentially change channel and phy mode.
919 */
920 ic->ic_curchan = chan;
921 ic->ic_rt = ieee80211_get_ratetable(chan);
922 IEEE80211_UNLOCK(ic);
923 /*
924 * Perform the channel change and scan unlocked so the driver
925 * may sleep. Once set_channel returns the hardware has
926 * completed the channel change.
927 */
928 ic->ic_set_channel(ic);
929 ieee80211_radiotap_chan_change(ic);
930
931 /*
932 * Scan curchan. Drivers for "intelligent hardware"
933 * override ic_scan_curchan to tell the device to do
934 * the work. Otherwise we manage the work outselves;
935 * sending a probe request (as needed), and arming the
936 * timeout to switch channels after maxdwell ticks.
937 *
938 * scan_curchan should only pause for the time required to
939 * prepare/initiate the hardware for the scan (if at all), the
940 * below condvar is used to sleep for the channels dwell time
941 * and allows it to be signalled for abort.
942 */
943 ic->ic_scan_curchan(ss, maxdwell);
944 IEEE80211_LOCK(ic);
945
946 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell;
947 /* clear mindwell lock and initial channel change flush */
948 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
949
950 if ((SCAN_PRIVATE(ss)->ss_iflags & (ISCAN_CANCEL|ISCAN_ABORT)))
951 continue;
952
953 /* Wait to be signalled to scan the next channel */
954 cv_wait(&SCAN_PRIVATE(ss)->ss_scan_cv, IEEE80211_LOCK_OBJ(ic));
955 }
956 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)
957 goto done;
958
959 IEEE80211_UNLOCK(ic);
960 ic->ic_scan_end(ic); /* notify driver */
961 IEEE80211_LOCK(ic);
962
963 /*
964 * Since a cancellation may have occured during one of the
965 * driver calls (whilst unlocked), update scandone.
966 */
967 if (scandone == 0 &&
968 ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0)) {
969 /* XXX printf? */
970 if_printf(vap->iv_ifp,
971 "%s: OOPS! scan cancelled during driver call!\n",
972 __func__);
973 }
974 scandone |= ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0);
975
976 /*
977 * Record scan complete time. Note that we also do
978 * this when canceled so any background scan will
979 * not be restarted for a while.
980 */
981 if (scandone)
982 ic->ic_lastscan = ticks;
983 /* return to the bss channel */
984 if (ic->ic_bsschan != IEEE80211_CHAN_ANYC &&
985 ic->ic_curchan != ic->ic_bsschan) {
986 ieee80211_setupcurchan(ic, ic->ic_bsschan);
987 IEEE80211_UNLOCK(ic);
988 ic->ic_set_channel(ic);
989 ieee80211_radiotap_chan_change(ic);
990 IEEE80211_LOCK(ic);
991 }
992 /* clear internal flags and any indication of a pick */
993 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP;
994 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK;
995
996 /*
997 * If not canceled and scan completed, do post-processing.
998 * If the callback function returns 0, then it wants to
999 * continue/restart scanning. Unfortunately we needed to
1000 * notify the driver to end the scan above to avoid having
1001 * rx frames alter the scan candidate list.
1002 */
1003 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 &&
1004 !ss->ss_ops->scan_end(ss, vap) &&
1005 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 &&
1006 time_before(ticks + ss->ss_mindwell, scanend)) {
1007 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1008 "%s: done, restart "
1009 "[ticks %u, dwell min %lu scanend %lu]\n",
1010 __func__,
1011 ticks, ss->ss_mindwell, scanend);
1012 ss->ss_next = 0; /* reset to begining */
1013 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE)
1014 vap->iv_stats.is_scan_active++;
1015 else
1016 vap->iv_stats.is_scan_passive++;
1017
1018 ss->ss_ops->scan_restart(ss, vap); /* XXX? */
1019 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task);
1020 IEEE80211_UNLOCK(ic);
1021 return;
1022 }
1023
1024 /* past here, scandone is ``true'' if not in bg mode */
1025 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0)
1026 scandone = 1;
1027
1028 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1029 "%s: %s, [ticks %u, dwell min %lu scanend %lu]\n",
1030 __func__, scandone ? "done" : "stopped",
1031 ticks, ss->ss_mindwell, scanend);
1032
1033 /*
1034 * Clear the SCAN bit first in case frames are
1035 * pending on the station power save queue. If
1036 * we defer this then the dispatch of the frames
1037 * may generate a request to cancel scanning.
1038 */
1039 done:
1040 ic->ic_flags &= ~IEEE80211_F_SCAN;
1041 /*
1042 * Drop out of power save mode when a scan has
1043 * completed. If this scan was prematurely terminated
1044 * because it is a background scan then don't notify
1045 * the ap; we'll either return to scanning after we
1046 * receive the beacon frame or we'll drop out of power
1047 * save mode because the beacon indicates we have frames
1048 * waiting for us.
1049 */
1050 if (scandone) {
1051 vap->iv_sta_ps(vap, 0);
1052 if (ss->ss_next >= ss->ss_last) {
1053 ieee80211_notify_scan_done(vap);
1054 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN;
1055 }
1056 }
1057 SCAN_PRIVATE(ss)->ss_iflags &= ~(ISCAN_CANCEL|ISCAN_ABORT);
1058 ss->ss_flags &= ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST);
1059 IEEE80211_UNLOCK(ic);
1060 #undef ISCAN_REP
1061 }
1062
1063 #ifdef IEEE80211_DEBUG
1064 static void
dump_country(const uint8_t * ie)1065 dump_country(const uint8_t *ie)
1066 {
1067 const struct ieee80211_country_ie *cie =
1068 (const struct ieee80211_country_ie *) ie;
1069 int i, nbands, schan, nchan;
1070
1071 if (cie->len < 3) {
1072 printf(" <bogus country ie, len %d>", cie->len);
1073 return;
1074 }
1075 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
1076 nbands = (cie->len - 3) / sizeof(cie->band[0]);
1077 for (i = 0; i < nbands; i++) {
1078 schan = cie->band[i].schan;
1079 nchan = cie->band[i].nchan;
1080 if (nchan != 1)
1081 printf(" %u-%u,%u", schan, schan + nchan-1,
1082 cie->band[i].maxtxpwr);
1083 else
1084 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
1085 }
1086 printf("]");
1087 }
1088
1089 static void
dump_probe_beacon(uint8_t subtype,int isnew,const uint8_t mac[IEEE80211_ADDR_LEN],const struct ieee80211_scanparams * sp,int rssi)1090 dump_probe_beacon(uint8_t subtype, int isnew,
1091 const uint8_t mac[IEEE80211_ADDR_LEN],
1092 const struct ieee80211_scanparams *sp, int rssi)
1093 {
1094
1095 printf("[%s] %s%s on chan %u (bss chan %u) ",
1096 ether_sprintf(mac), isnew ? "new " : "",
1097 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1098 sp->chan, sp->bchan);
1099 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1100 printf(" rssi %d\n", rssi);
1101
1102 if (isnew) {
1103 printf("[%s] caps 0x%x bintval %u erp 0x%x",
1104 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1105 if (sp->country != NULL)
1106 dump_country(sp->country);
1107 printf("\n");
1108 }
1109 }
1110 #endif /* IEEE80211_DEBUG */
1111
1112 /*
1113 * Process a beacon or probe response frame.
1114 */
1115 void
ieee80211_add_scan(struct ieee80211vap * vap,const struct ieee80211_scanparams * sp,const struct ieee80211_frame * wh,int subtype,int rssi,int noise)1116 ieee80211_add_scan(struct ieee80211vap *vap,
1117 const struct ieee80211_scanparams *sp,
1118 const struct ieee80211_frame *wh,
1119 int subtype, int rssi, int noise)
1120 {
1121 struct ieee80211com *ic = vap->iv_ic;
1122 struct ieee80211_scan_state *ss = ic->ic_scan;
1123
1124 /* XXX locking */
1125 /*
1126 * Frames received during startup are discarded to avoid
1127 * using scan state setup on the initial entry to the timer
1128 * callback. This can occur because the device may enable
1129 * rx prior to our doing the initial channel change in the
1130 * timer routine.
1131 */
1132 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD)
1133 return;
1134 #ifdef IEEE80211_DEBUG
1135 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN))
1136 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi);
1137 #endif
1138 if (ss->ss_ops != NULL &&
1139 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise)) {
1140 /*
1141 * If we've reached the min dwell time terminate
1142 * the timer so we'll switch to the next channel.
1143 */
1144 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 &&
1145 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) {
1146 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1147 "%s: chan %3d%c min dwell met (%u > %lu)\n",
1148 __func__,
1149 ieee80211_chan2ieee(ic, ic->ic_curchan),
1150 channel_type(ic->ic_curchan),
1151 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell);
1152 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL;
1153 /*
1154 * NB: trigger at next clock tick or wait for the
1155 * hardware.
1156 */
1157 ic->ic_scan_mindwell(ss);
1158 }
1159 }
1160 }
1161
1162 /*
1163 * Timeout/age scan cache entries; called from sta timeout
1164 * timer (XXX should be self-contained).
1165 */
1166 void
ieee80211_scan_timeout(struct ieee80211com * ic)1167 ieee80211_scan_timeout(struct ieee80211com *ic)
1168 {
1169 struct ieee80211_scan_state *ss = ic->ic_scan;
1170
1171 if (ss->ss_ops != NULL)
1172 ss->ss_ops->scan_age(ss);
1173 }
1174
1175 /*
1176 * Mark a scan cache entry after a successful associate.
1177 */
1178 void
ieee80211_scan_assoc_success(struct ieee80211vap * vap,const uint8_t mac[])1179 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
1180 {
1181 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1182
1183 if (ss->ss_ops != NULL) {
1184 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
1185 mac, "%s", __func__);
1186 ss->ss_ops->scan_assoc_success(ss, mac);
1187 }
1188 }
1189
1190 /*
1191 * Demerit a scan cache entry after failing to associate.
1192 */
1193 void
ieee80211_scan_assoc_fail(struct ieee80211vap * vap,const uint8_t mac[],int reason)1194 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
1195 const uint8_t mac[], int reason)
1196 {
1197 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1198
1199 if (ss->ss_ops != NULL) {
1200 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
1201 "%s: reason %u", __func__, reason);
1202 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
1203 }
1204 }
1205
1206 /*
1207 * Iterate over the contents of the scan cache.
1208 */
1209 void
ieee80211_scan_iterate(struct ieee80211vap * vap,ieee80211_scan_iter_func * f,void * arg)1210 ieee80211_scan_iterate(struct ieee80211vap *vap,
1211 ieee80211_scan_iter_func *f, void *arg)
1212 {
1213 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1214
1215 if (ss->ss_ops != NULL)
1216 ss->ss_ops->scan_iterate(ss, f, arg);
1217 }
1218
1219 /*
1220 * Flush the contents of the scan cache.
1221 */
1222 void
ieee80211_scan_flush(struct ieee80211vap * vap)1223 ieee80211_scan_flush(struct ieee80211vap *vap)
1224 {
1225 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
1226
1227 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
1228 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
1229 ss->ss_ops->scan_flush(ss);
1230 }
1231 }
1232
1233 /*
1234 * Check the scan cache for an ap/channel to use; if that
1235 * fails then kick off a new scan.
1236 */
1237 struct ieee80211_channel *
ieee80211_scan_pickchannel(struct ieee80211com * ic,int flags)1238 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
1239 {
1240 struct ieee80211_scan_state *ss = ic->ic_scan;
1241
1242 IEEE80211_LOCK_ASSERT(ic);
1243
1244 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
1245 /* XXX printf? */
1246 return NULL;
1247 }
1248 if (ss->ss_ops->scan_pickchan == NULL) {
1249 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
1250 "%s: scan module does not support picking a channel, "
1251 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
1252 return NULL;
1253 }
1254 return ss->ss_ops->scan_pickchan(ss, flags);
1255 }
1256