2 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
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.
25 * $FreeBSD: head/sys/net80211/ieee80211_scan_sta.c 196005 2009-07-31 19:13:16Z sam $
30 * IEEE 802.11 station scanning support.
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/module.h>
40 #include <sys/socket.h>
43 #include <net/if_media.h>
44 #include <net/ethernet.h>
45 #include <net/route.h>
47 #include <netproto/802_11/ieee80211_var.h>
48 #include <netproto/802_11/ieee80211_input.h>
49 #include <netproto/802_11/ieee80211_regdomain.h>
50 #ifdef IEEE80211_SUPPORT_TDMA
51 #include <netproto/802_11/ieee80211_tdma.h>
53 #ifdef IEEE80211_SUPPORT_MESH
54 #include <netproto/802_11/ieee80211_mesh.h>
60 * Parameters for managing cache entries:
62 * o a station with STA_FAILS_MAX failures is not considered
63 * when picking a candidate
64 * o a station that hasn't had an update in STA_PURGE_SCANS
65 * (background) scans is discarded
66 * o after STA_FAILS_AGE seconds we clear the failure count
68 #define STA_FAILS_MAX 2 /* assoc failures before ignored */
69 #define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */
70 #define STA_PURGE_SCANS 2 /* age for purging entries (scans) */
73 #define STA_RSSI_MIN 8 /* min acceptable rssi */
74 #define STA_RSSI_MAX 40 /* max rssi for comparison */
77 struct ieee80211_scan_entry base;
78 TAILQ_ENTRY(sta_entry) se_list;
79 LIST_ENTRY(sta_entry) se_hash;
80 uint8_t se_fails; /* failure to associate count */
81 uint8_t se_seen; /* seen during current scan */
82 uint8_t se_notseen; /* not seen in previous scans */
84 #define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */
85 uint32_t se_avgrssi; /* LPF rssi state */
86 unsigned long se_lastupdate; /* time of last update */
87 unsigned long se_lastfail; /* time of last failure */
88 unsigned long se_lastassoc; /* time of last association */
89 u_int se_scangen; /* iterator scan gen# */
90 u_int se_countrygen; /* gen# of last cc notify */
93 #define STA_HASHSIZE 32
94 /* simple hash is enough for variation of macaddr */
95 #define STA_HASH(addr) \
96 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE)
98 #define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */
99 CTASSERT(MAX_IEEE_CHAN >= 256);
102 struct lock st_lock; /* on scan table */
103 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */
104 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE];
105 struct lock st_scanlock; /* on st_scaniter */
106 u_int st_scaniter; /* gen# for iterator */
107 u_int st_scangen; /* scan generation # */
109 /* ap-related state */
110 int st_maxrssi[MAX_IEEE_CHAN];
113 static void sta_flush_table(struct sta_table *);
115 * match_bss returns a bitmask describing if an entry is suitable
116 * for use. If non-zero the entry was deemed not suitable and it's
117 * contents explains why. The following flags are or'd to to this
118 * mask and can be used to figure out why the entry was rejected.
120 #define MATCH_CHANNEL 0x00001 /* channel mismatch */
121 #define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */
122 #define MATCH_PRIVACY 0x00004 /* privacy mismatch */
123 #define MATCH_RATE 0x00008 /* rate set mismatch */
124 #define MATCH_SSID 0x00010 /* ssid mismatch */
125 #define MATCH_BSSID 0x00020 /* bssid mismatch */
126 #define MATCH_FAILS 0x00040 /* too many failed auth attempts */
127 #define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */
128 #define MATCH_RSSI 0x00100 /* rssi deemed too low to use */
129 #define MATCH_CC 0x00200 /* country code mismatch */
130 #define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */
131 #define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */
132 #define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */
133 #define MATCH_TDMA_LOCAL 0x02000 /* local address */
134 #define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */
135 #define MATCH_MESH_NOID 0x10000 /* no MESHID ie */
136 #define MATCH_MESHID 0x20000 /* meshid mismatch */
137 static int match_bss(struct ieee80211vap *,
138 const struct ieee80211_scan_state *, struct sta_entry *, int);
139 static void adhoc_age(struct ieee80211_scan_state *);
142 isocmp(const uint8_t cc1[], const uint8_t cc2[])
144 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]);
147 /* number of references from net80211 layer */
148 static int nrefs = 0;
152 IEEE80211_SCANNER_MODULE(sta, 1);
155 * Attach prior to any scanning work.
158 sta_attach(struct ieee80211_scan_state *ss)
160 struct sta_table *st;
162 st = (struct sta_table *) kmalloc(sizeof(struct sta_table),
163 M_80211_SCAN, M_INTWAIT | M_ZERO);
166 lockinit(&st->st_lock, "scantable", 0, 0);
167 lockinit(&st->st_scanlock, "scangen", 0, 0);
168 TAILQ_INIT(&st->st_entry);
170 nrefs++; /* NB: we assume caller locking */
175 * Cleanup any private state.
178 sta_detach(struct ieee80211_scan_state *ss)
180 struct sta_table *st = ss->ss_priv;
184 lockuninit(&st->st_lock);
185 lockuninit(&st->st_scanlock);
186 kfree(st, M_80211_SCAN);
187 KASSERT(nrefs > 0, ("imbalanced attach/detach"));
188 nrefs--; /* NB: we assume caller locking */
194 * Flush all per-scan state.
197 sta_flush(struct ieee80211_scan_state *ss)
199 struct sta_table *st = ss->ss_priv;
201 lockmgr(&st->st_lock, LK_EXCLUSIVE);
203 lockmgr(&st->st_lock, LK_RELEASE);
209 * Flush all entries in the scan cache.
212 sta_flush_table(struct sta_table *st)
214 struct sta_entry *se, *next;
216 TAILQ_FOREACH_MUTABLE(se, &st->st_entry, se_list, next) {
217 TAILQ_REMOVE(&st->st_entry, se, se_list);
218 LIST_REMOVE(se, se_hash);
219 ieee80211_ies_cleanup(&se->base.se_ies);
220 kfree(se, M_80211_SCAN);
222 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi));
226 * Process a beacon or probe response frame; create an
227 * entry in the scan cache or update any previous entry.
230 sta_add(struct ieee80211_scan_state *ss,
231 const struct ieee80211_scanparams *sp,
232 const struct ieee80211_frame *wh,
233 int subtype, int rssi, int noise)
235 #define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
236 #define PICK1ST(_ss) \
237 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \
238 IEEE80211_SCAN_PICK1ST)
239 struct sta_table *st = ss->ss_priv;
240 const uint8_t *macaddr = wh->i_addr2;
241 struct ieee80211vap *vap = ss->ss_vap;
242 struct ieee80211com *ic = vap->iv_ic;
243 struct sta_entry *se;
244 struct ieee80211_scan_entry *ise;
247 hash = STA_HASH(macaddr);
249 lockmgr(&st->st_lock, LK_EXCLUSIVE);
250 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
251 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
253 se = (struct sta_entry *) kmalloc(sizeof(struct sta_entry),
254 M_80211_SCAN, M_INTWAIT | M_ZERO);
256 lockmgr(&st->st_lock, LK_RELEASE);
259 se->se_scangen = st->st_scaniter-1;
260 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER;
261 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr);
262 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list);
263 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash);
266 /* XXX ap beaconing multiple ssid w/ same bssid */
267 if (sp->ssid[1] != 0 &&
268 (ISPROBE(subtype) || ise->se_ssid[1] == 0))
269 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]);
270 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE,
271 ("rate set too large: %u", sp->rates[1]));
272 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]);
273 if (sp->xrates != NULL) {
274 /* XXX validate xrates[1] */
275 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE,
276 ("xrate set too large: %u", sp->xrates[1]));
277 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]);
279 ise->se_xrates[1] = 0;
280 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3);
281 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) {
283 * Record rssi data using extended precision LPF filter.
285 * NB: use only on-channel data to insure we get a good
286 * estimate of the signal we'll see when associated.
288 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi);
289 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi);
290 ise->se_noise = noise;
292 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp));
293 ise->se_intval = sp->bintval;
294 ise->se_capinfo = sp->capinfo;
295 #ifdef IEEE80211_SUPPORT_MESH
296 if (sp->meshid != NULL && sp->meshid[1] != 0)
297 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]);
300 * Beware of overriding se_chan for frames seen
301 * off-channel; this can cause us to attempt an
302 * association on the wrong channel.
304 if (sp->status & IEEE80211_BPARSE_OFFCHAN) {
305 struct ieee80211_channel *c;
307 * Off-channel, locate the home/bss channel for the sta
308 * using the value broadcast in the DSPARMS ie. We know
309 * sp->chan has this value because it's used to calculate
310 * IEEE80211_BPARSE_OFFCHAN.
312 c = ieee80211_find_channel_byieee(ic, sp->chan,
313 ic->ic_curchan->ic_flags);
316 } else if (ise->se_chan == NULL) {
317 /* should not happen, pick something */
318 ise->se_chan = ic->ic_curchan;
321 ise->se_chan = ic->ic_curchan;
322 ise->se_fhdwell = sp->fhdwell;
323 ise->se_fhindex = sp->fhindex;
324 ise->se_erp = sp->erp;
325 ise->se_timoff = sp->timoff;
326 if (sp->tim != NULL) {
327 const struct ieee80211_tim_ie *tim =
328 (const struct ieee80211_tim_ie *) sp->tim;
329 ise->se_dtimperiod = tim->tim_period;
331 if (sp->country != NULL) {
332 const struct ieee80211_country_ie *cie =
333 (const struct ieee80211_country_ie *) sp->country;
335 * If 11d is enabled and we're attempting to join a bss
336 * that advertises it's country code then compare our
337 * current settings to what we fetched from the country ie.
338 * If our country code is unspecified or different then
339 * dispatch an event to user space that identifies the
340 * country code so our regdomain config can be changed.
342 /* XXX only for STA mode? */
343 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) ||
344 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
345 (ic->ic_regdomain.country == CTRY_DEFAULT ||
346 !isocmp(cie->cc, ic->ic_regdomain.isocc))) {
347 /* only issue one notify event per scan */
348 if (se->se_countrygen != st->st_scangen) {
349 ieee80211_notify_country(vap, ise->se_bssid,
351 se->se_countrygen = st->st_scangen;
354 ise->se_cc[0] = cie->cc[0];
355 ise->se_cc[1] = cie->cc[1];
357 /* NB: no need to setup ie ptrs; they are not (currently) used */
358 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len);
360 /* clear failure count after STA_FAIL_AGE passes */
361 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) {
363 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr,
364 "%s: fails %u", __func__, se->se_fails);
367 se->se_lastupdate = ticks; /* update time */
371 KASSERT(sizeof(sp->bchan) == 1, ("bchan size"));
372 if (rssi > st->st_maxrssi[sp->bchan])
373 st->st_maxrssi[sp->bchan] = rssi;
375 lockmgr(&st->st_lock, LK_RELEASE);
378 * If looking for a quick choice and nothing's
379 * been found check here.
381 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0)
382 ss->ss_flags |= IEEE80211_SCAN_GOTPICK;
390 * Check if a channel is excluded by user request.
393 isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c)
395 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) ||
396 (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
397 c->ic_freq != vap->iv_des_chan->ic_freq));
400 static struct ieee80211_channel *
401 find11gchannel(struct ieee80211com *ic, int i, int freq)
403 struct ieee80211_channel *c;
407 * The normal ordering in the channel list is b channel
408 * immediately followed by g so optimize the search for
409 * this. We'll still do a full search just in case.
411 for (j = i+1; j < ic->ic_nchans; j++) {
412 c = &ic->ic_channels[j];
413 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c))
416 for (j = 0; j < i; j++) {
417 c = &ic->ic_channels[j];
418 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c))
424 static const u_int chanflags[IEEE80211_MODE_MAX] = {
425 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B,
426 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A,
427 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B,
428 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G,
429 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS,
430 /* check base channel */
431 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A,
432 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G,
433 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST,
434 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF,
435 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER,
437 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A,
438 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G,
442 add_channels(struct ieee80211vap *vap,
443 struct ieee80211_scan_state *ss,
444 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq)
446 #define N(a) (sizeof(a) / sizeof(a[0]))
447 struct ieee80211com *ic = vap->iv_ic;
448 struct ieee80211_channel *c, *cg;
452 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode));
453 modeflags = chanflags[mode];
454 for (i = 0; i < nfreq; i++) {
455 if (ss->ss_last >= IEEE80211_SCAN_MAX)
458 c = ieee80211_find_channel(ic, freq[i], modeflags);
459 if (c == NULL || isexcluded(vap, c))
461 if (mode == IEEE80211_MODE_AUTO) {
463 * XXX special-case 11b/g channels so we select
464 * the g channel if both are present.
466 if (IEEE80211_IS_CHAN_B(c) &&
467 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL)
470 ss->ss_chans[ss->ss_last++] = c;
478 const uint16_t *list;
482 checktable(const struct scanlist *scan, const struct ieee80211_channel *c)
486 for (; scan->list != NULL; scan++) {
487 for (i = 0; i < scan->count; i++)
488 if (scan->list[i] == c->ic_freq)
495 onscanlist(const struct ieee80211_scan_state *ss,
496 const struct ieee80211_channel *c)
500 for (i = 0; i < ss->ss_last; i++)
501 if (ss->ss_chans[i] == c)
507 sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
508 const struct scanlist table[])
510 struct ieee80211com *ic = vap->iv_ic;
511 struct ieee80211_channel *c;
514 for (i = 0; i < ic->ic_nchans; i++) {
515 if (ss->ss_last >= IEEE80211_SCAN_MAX)
518 c = &ic->ic_channels[i];
520 * Ignore dynamic turbo channels; we scan them
521 * in normal mode (i.e. not boosted). Likewise
522 * for HT channels, they get scanned using
525 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c))
529 * If a desired mode was specified, scan only
530 * channels that satisfy that constraint.
532 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
533 vap->iv_des_mode != ieee80211_chan2mode(c))
537 * Skip channels excluded by user request.
539 if (isexcluded(vap, c))
543 * Add the channel unless it is listed in the
544 * fixed scan order tables. This insures we
545 * don't sweep back in channels we filtered out
548 if (checktable(table, c))
551 /* Add channel to scanning list. */
552 ss->ss_chans[ss->ss_last++] = c;
555 * Explicitly add any desired channel if:
556 * - not already on the scan list
557 * - allowed by any desired mode constraint
558 * - there is space in the scan list
559 * This allows the channel to be used when the filtering
560 * mechanisms would otherwise elide it (e.g HT, turbo).
562 c = vap->iv_des_chan;
563 if (c != IEEE80211_CHAN_ANYC &&
564 !onscanlist(ss, c) &&
565 (vap->iv_des_mode == IEEE80211_MODE_AUTO ||
566 vap->iv_des_mode == ieee80211_chan2mode(c)) &&
567 ss->ss_last < IEEE80211_SCAN_MAX)
568 ss->ss_chans[ss->ss_last++] = c;
572 makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
573 const struct scanlist table[])
575 const struct scanlist *scan;
576 enum ieee80211_phymode mode;
580 * Use the table of ordered channels to construct the list
581 * of channels for scanning. Any channels in the ordered
582 * list not in the master list will be discarded.
584 for (scan = table; scan->list != NULL; scan++) {
586 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) {
588 * If a desired mode was specified, scan only
589 * channels that satisfy that constraint.
591 if (vap->iv_des_mode != mode) {
593 * The scan table marks 2.4Ghz channels as b
594 * so if the desired mode is 11g, then use
595 * the 11b channel list but upgrade the mode.
597 if (vap->iv_des_mode != IEEE80211_MODE_11G ||
598 mode != IEEE80211_MODE_11B)
600 mode = IEEE80211_MODE_11G; /* upgrade */
604 * This lets add_channels upgrade an 11b channel
605 * to 11g if available.
607 if (mode == IEEE80211_MODE_11B)
608 mode = IEEE80211_MODE_AUTO;
610 #ifdef IEEE80211_F_XR
611 /* XR does not operate on turbo channels */
612 if ((vap->iv_flags & IEEE80211_F_XR) &&
613 (mode == IEEE80211_MODE_TURBO_A ||
614 mode == IEEE80211_MODE_TURBO_G ||
615 mode == IEEE80211_MODE_STURBO_A))
619 * Add the list of the channels; any that are not
620 * in the master channel list will be discarded.
622 add_channels(vap, ss, mode, scan->list, scan->count);
626 * Add the channels from the ic that are not present
629 sweepchannels(ss, vap, table);
632 static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */
633 { 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 };
634 static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */
635 { 5170, 5190, 5210, 5230 };
636 static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */
637 { 2412, 2437, 2462, 2442, 2472 };
638 static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */
639 { 5745, 5765, 5785, 5805, 5825 };
640 static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */
641 { 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 };
642 static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */
643 { 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 };
644 static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */
646 static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */
647 { 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 };
648 static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */
649 { 5040, 5060, 5080, 4920, 4940, 4960, 4980 };
650 #ifdef ATH_TURBO_SCAN
651 static const uint16_t rcl5[] = /* 3 static turbo channels */
652 { 5210, 5250, 5290 };
653 static const uint16_t rcl6[] = /* 2 static turbo channels */
655 static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */
656 { 5540, 5580, 5620, 5660 };
657 static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */
659 static const uint16_t rcl13[] = /* dynamic Turbo channels */
660 { 5200, 5240, 5280, 5765, 5805 };
661 #endif /* ATH_TURBO_SCAN */
663 #define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a
665 static const struct scanlist staScanTable[] = {
666 { IEEE80211_MODE_11B, X(rcl3) },
667 { IEEE80211_MODE_11A, X(rcl1) },
668 { IEEE80211_MODE_11A, X(rcl2) },
669 { IEEE80211_MODE_11B, X(rcl8) },
670 { IEEE80211_MODE_11B, X(rcl9) },
671 { IEEE80211_MODE_11A, X(rcl4) },
672 #ifdef ATH_TURBO_SCAN
673 { IEEE80211_MODE_STURBO_A, X(rcl5) },
674 { IEEE80211_MODE_STURBO_A, X(rcl6) },
675 { IEEE80211_MODE_TURBO_A, X(rcl6x) },
676 { IEEE80211_MODE_TURBO_A, X(rcl13) },
677 #endif /* ATH_TURBO_SCAN */
678 { IEEE80211_MODE_11A, X(rcl7) },
679 { IEEE80211_MODE_11B, X(rcl10) },
680 { IEEE80211_MODE_11A, X(rcl11) },
681 #ifdef ATH_TURBO_SCAN
682 { IEEE80211_MODE_TURBO_G, X(rcl12) },
683 #endif /* ATH_TURBO_SCAN */
688 * Start a station-mode scan by populating the channel list.
691 sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
693 struct sta_table *st = ss->ss_priv;
695 makescanlist(ss, vap, staScanTable);
697 if (ss->ss_mindwell == 0)
698 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */
699 if (ss->ss_maxdwell == 0)
700 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
709 * Restart a scan, typically a bg scan but can
710 * also be a fg scan that came up empty.
713 sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
715 struct sta_table *st = ss->ss_priv;
722 * Cancel an ongoing scan.
725 sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
730 /* unalligned little endian access */
731 #define LE_READ_2(p) \
733 ((((const uint8_t *)(p))[0] ) | \
734 (((const uint8_t *)(p))[1] << 8)))
737 * Demote any supplied 11g channel to 11b. There should
738 * always be an 11b channel but we check anyway...
740 static struct ieee80211_channel *
741 demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan)
743 struct ieee80211_channel *c;
745 if (IEEE80211_IS_CHAN_ANYG(chan) &&
746 vap->iv_des_mode == IEEE80211_MODE_AUTO) {
747 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq,
748 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) |
757 maxrate(const struct ieee80211_scan_entry *se)
759 const struct ieee80211_ie_htcap *htcap =
760 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie;
767 * HT station; inspect supported MCS and then adjust
768 * rate by channel width. Could also include short GI
769 * in this if we want to be extra accurate.
771 /* XXX assumes MCS15 is max */
772 for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--)
775 caps = LE_READ_2(&htcap->hc_cap);
776 /* XXX short/long GI */
777 if (caps & IEEE80211_HTCAP_CHWIDTH40)
778 rmax = ieee80211_htrates[i].ht40_rate_400ns;
780 rmax = ieee80211_htrates[i].ht40_rate_800ns;
783 for (i = 0; i < se->se_rates[1]; i++) {
784 r = se->se_rates[2+i] & IEEE80211_RATE_VAL;
788 for (i = 0; i < se->se_xrates[1]; i++) {
789 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL;
797 * Compare the capabilities of two entries and decide which is
798 * more desirable (return >0 if a is considered better). Note
799 * that we assume compatibility/usability has already been checked
800 * so we don't need to (e.g. validate whether privacy is supported).
801 * Used to select the best scan candidate for association in a BSS.
804 sta_compare(const struct sta_entry *a, const struct sta_entry *b)
806 #define PREFER(_a,_b,_what) do { \
807 if (((_a) ^ (_b)) & (_what)) \
808 return ((_a) & (_what)) ? 1 : -1; \
810 #define ABS(_a) ((_a) < 0 ? -(_a) : (_a))
815 /* privacy support */
816 PREFER(a->base.se_capinfo, b->base.se_capinfo,
817 IEEE80211_CAPINFO_PRIVACY);
819 /* compare count of previous failures */
820 weight = b->se_fails - a->se_fails;
825 * Compare rssi. If the two are considered equivalent
826 * then fallback to other criteria. We threshold the
827 * comparisons to avoid selecting an ap purely by rssi
828 * when both values may be good but one ap is otherwise
829 * more desirable (e.g. an 11b-only ap with stronger
830 * signal than an 11g ap).
832 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX);
833 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX);
834 if (ABS(rssib - rssia) < 5) {
835 /* best/max rate preferred if signal level close enough XXX */
836 maxa = maxrate(&a->base);
837 maxb = maxrate(&b->base);
840 /* XXX use freq for channel preference */
841 /* for now just prefer 5Ghz band to all other bands */
842 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan),
843 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1);
845 /* all things being equal, use signal level */
846 return a->base.se_rssi - b->base.se_rssi;
852 * Check rate set suitability and return the best supported rate.
853 * XXX inspect MCS for HT
856 check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan,
857 const struct ieee80211_scan_entry *se)
859 #define RV(v) ((v) & IEEE80211_RATE_VAL)
860 const struct ieee80211_rateset *srs;
861 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate;
864 okrate = badrate = 0;
866 srs = ieee80211_get_suprates(vap->iv_ic, chan);
867 nrs = se->se_rates[1];
870 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate;
871 fixedrate = IEEE80211_FIXED_RATE_NONE;
873 for (i = 0; i < nrs; i++) {
877 * Check any fixed rate is included.
882 * Check against our supported rates.
884 for (j = 0; j < srs->rs_nrates; j++)
885 if (r == RV(srs->rs_rates[j])) {
886 if (r > okrate) /* NB: track max */
891 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) {
893 * Don't try joining a BSS, if we don't support
894 * one of its basic rates.
900 if (rs == se->se_rates+2) {
901 /* scan xrates too; sort of an algol68-style for loop */
902 nrs = se->se_xrates[1];
903 rs = se->se_xrates+2;
908 if (okrate == 0 || ucastrate != fixedrate)
909 return badrate | IEEE80211_RATE_BASIC;
916 match_id(const uint8_t *ie, const uint8_t *val, int len)
918 return (ie[1] == len && memcmp(ie+2, val, len) == 0);
922 match_ssid(const uint8_t *ie,
923 int nssid, const struct ieee80211_scan_ssid ssids[])
927 for (i = 0; i < nssid; i++) {
928 if (match_id(ie, ssids[i].ssid, ssids[i].len))
934 #ifdef IEEE80211_SUPPORT_TDMA
936 tdma_isfull(const struct ieee80211_tdma_param *tdma)
940 slotcnt = tdma->tdma_slotcnt;
941 for (slot = slotcnt-1; slot >= 0; slot--)
942 if (isclr(tdma->tdma_inuse, slot))
946 #endif /* IEEE80211_SUPPORT_TDMA */
949 * Test a scan candidate for suitability/compatibility.
952 match_bss(struct ieee80211vap *vap,
953 const struct ieee80211_scan_state *ss, struct sta_entry *se0,
956 struct ieee80211com *ic = vap->iv_ic;
957 struct ieee80211_scan_entry *se = &se0->base;
962 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan)))
963 fail |= MATCH_CHANNEL;
965 * NB: normally the desired mode is used to construct
966 * the channel list, but it's possible for the scan
967 * cache to include entries for stations outside this
968 * list so we check the desired mode here to weed them
971 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
972 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) !=
973 chanflags[vap->iv_des_mode])
974 fail |= MATCH_CHANNEL;
975 if (vap->iv_opmode == IEEE80211_M_IBSS) {
976 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
977 fail |= MATCH_CAPINFO;
978 #ifdef IEEE80211_SUPPORT_TDMA
979 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) {
981 * Adhoc demo network setup shouldn't really be scanning
982 * but just in case skip stations operating in IBSS or
985 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS))
986 fail |= MATCH_CAPINFO;
988 * TDMA operation cannot coexist with a normal 802.11 network;
989 * skip if IBSS or ESS capabilities are marked and require
990 * the beacon have a TDMA ie present.
992 if (vap->iv_caps & IEEE80211_C_TDMA) {
993 const struct ieee80211_tdma_param *tdma =
994 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie;
995 const struct ieee80211_tdma_state *ts = vap->iv_tdma;
998 fail |= MATCH_TDMA_NOIE;
999 else if (tdma->tdma_version != ts->tdma_version)
1000 fail |= MATCH_TDMA_VERSION;
1001 else if (tdma->tdma_slot != 0)
1002 fail |= MATCH_TDMA_NOTMASTER;
1003 else if (tdma_isfull(tdma))
1004 fail |= MATCH_TDMA_NOSLOT;
1006 else if (ieee80211_local_address(se->se_macaddr))
1007 fail |= MATCH_TDMA_LOCAL;
1010 #endif /* IEEE80211_SUPPORT_TDMA */
1011 #ifdef IEEE80211_SUPPORT_MESH
1012 } else if (vap->iv_opmode == IEEE80211_M_MBSS) {
1013 const struct ieee80211_mesh_state *ms = vap->iv_mesh;
1015 * Mesh nodes have IBSS & ESS bits in capinfo turned off
1016 * and two special ie's that must be present.
1018 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS))
1019 fail |= MATCH_CAPINFO;
1020 else if (&se->se_meshid == NULL)
1021 fail |= MATCH_MESH_NOID;
1022 else if (ms->ms_idlen != 0 &&
1023 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen))
1024 fail |= MATCH_MESHID;
1027 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0)
1028 fail |= MATCH_CAPINFO;
1030 * If 11d is enabled and we're attempting to join a bss
1031 * that advertises it's country code then compare our
1032 * current settings to what we fetched from the country ie.
1033 * If our country code is unspecified or different then do
1034 * not attempt to join the bss. We should have already
1035 * dispatched an event to user space that identifies the
1036 * new country code so our regdomain config should match.
1038 if ((IEEE80211_IS_CHAN_11D(se->se_chan) ||
1039 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
1040 se->se_cc[0] != 0 &&
1041 (ic->ic_regdomain.country == CTRY_DEFAULT ||
1042 !isocmp(se->se_cc, ic->ic_regdomain.isocc)))
1045 if (vap->iv_flags & IEEE80211_F_PRIVACY) {
1046 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
1047 fail |= MATCH_PRIVACY;
1049 /* XXX does this mean privacy is supported or required? */
1050 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY)
1051 fail |= MATCH_PRIVACY;
1053 se0->se_flags &= ~STA_DEMOTE11B;
1054 rate = check_rate(vap, se->se_chan, se);
1055 if (rate & IEEE80211_RATE_BASIC) {
1058 * An 11b-only ap will give a rate mismatch if there is an
1059 * OFDM fixed tx rate for 11g. Try downgrading the channel
1060 * in the scan list to 11b and retry the rate check.
1062 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) {
1063 rate = check_rate(vap, demote11b(vap, se->se_chan), se);
1064 if ((rate & IEEE80211_RATE_BASIC) == 0) {
1065 fail &= ~MATCH_RATE;
1066 se0->se_flags |= STA_DEMOTE11B;
1069 } else if (rate < 2*24) {
1071 * This is an 11b-only ap. Check the desired mode in
1072 * case that needs to be honored (mode 11g filters out
1073 * 11b-only ap's). Otherwise force any 11g channel used
1074 * in scanning to be demoted.
1076 * NB: we cheat a bit here by looking at the max rate;
1077 * we could/should check the rates.
1079 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO ||
1080 vap->iv_des_mode == IEEE80211_MODE_11B))
1083 se0->se_flags |= STA_DEMOTE11B;
1085 if (ss->ss_nssid != 0 &&
1086 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid))
1088 if ((vap->iv_flags & IEEE80211_F_DESBSSID) &&
1089 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid))
1090 fail |= MATCH_BSSID;
1091 if (se0->se_fails >= STA_FAILS_MAX)
1092 fail |= MATCH_FAILS;
1093 if (se0->se_notseen >= STA_PURGE_SCANS)
1094 fail |= MATCH_NOTSEEN;
1095 if (se->se_rssi < STA_RSSI_MIN)
1097 #ifdef IEEE80211_DEBUG
1098 if (ieee80211_msg(vap, debug)) {
1100 fail & MATCH_FAILS ? '=' :
1101 fail & MATCH_NOTSEEN ? '^' :
1102 fail & MATCH_CC ? '$' :
1103 #ifdef IEEE80211_SUPPORT_TDMA
1104 fail & MATCH_TDMA_NOIE ? '&' :
1105 fail & MATCH_TDMA_VERSION ? 'v' :
1106 fail & MATCH_TDMA_NOTMASTER ? 's' :
1107 fail & MATCH_TDMA_NOSLOT ? 'f' :
1108 fail & MATCH_TDMA_LOCAL ? 'l' :
1110 fail & MATCH_MESH_NOID ? 'm' :
1111 fail ? '-' : '+', se->se_macaddr, ":");
1112 kprintf(" %6D%c", se->se_bssid, ":",
1113 fail & MATCH_BSSID ? '!' : ' ');
1114 kprintf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan),
1115 fail & MATCH_CHANNEL ? '!' : ' ');
1116 kprintf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' ');
1117 kprintf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
1118 fail & MATCH_RATE ? '!' : ' ');
1120 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
1121 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "",
1122 fail & MATCH_CAPINFO ? '!' : ' ');
1124 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
1126 fail & MATCH_PRIVACY ? '!' : ' ');
1127 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]);
1128 kprintf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : "");
1135 sta_update_notseen(struct sta_table *st)
1137 struct sta_entry *se;
1139 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1140 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1142 * If seen the reset and don't bump the count;
1143 * otherwise bump the ``not seen'' count. Note
1144 * that this insures that stations for which we
1145 * see frames while not scanning but not during
1146 * this scan will not be penalized.
1153 lockmgr(&st->st_lock, LK_RELEASE);
1157 sta_dec_fails(struct sta_table *st)
1159 struct sta_entry *se;
1161 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1162 TAILQ_FOREACH(se, &st->st_entry, se_list)
1165 lockmgr(&st->st_lock, LK_RELEASE);
1168 static struct sta_entry *
1169 select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug)
1171 struct sta_table *st = ss->ss_priv;
1172 struct sta_entry *se, *selbs = NULL;
1174 IEEE80211_DPRINTF(vap, debug, " %s\n",
1175 "macaddr bssid chan rssi rate flag wep essid");
1176 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1177 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1178 ieee80211_ies_expand(&se->base.se_ies);
1179 if (match_bss(vap, ss, se, debug) == 0) {
1182 else if (sta_compare(se, selbs) > 0)
1186 lockmgr(&st->st_lock, LK_RELEASE);
1192 * Pick an ap or ibss network to join or find a channel
1193 * to use to start an ibss network.
1196 sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1198 struct sta_table *st = ss->ss_priv;
1199 struct sta_entry *selbs;
1200 struct ieee80211_channel *chan;
1202 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1203 ("wrong mode %u", vap->iv_opmode));
1205 if (st->st_newscan) {
1206 sta_update_notseen(st);
1209 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1211 * Manual/background scan, don't select+join the
1212 * bss, just return. The scanning framework will
1213 * handle notification that this has completed.
1215 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1219 * Automatic sequencing; look for a candidate and
1220 * if found join the network.
1222 /* NB: unlocked read should be ok */
1223 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1224 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1225 "%s: no scan candidate\n", __func__);
1226 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1230 * If nothing suitable was found decrement
1231 * the failure counts so entries will be
1232 * reconsidered the next time around. We
1233 * really want to do this only for sta's
1234 * where we've previously had some success.
1238 return 0; /* restart scan */
1240 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1241 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1242 return (selbs != NULL);
1245 chan = selbs->base.se_chan;
1246 if (selbs->se_flags & STA_DEMOTE11B)
1247 chan = demote11b(vap, chan);
1248 if (!ieee80211_sta_join(vap, chan, &selbs->base))
1250 return 1; /* terminate scan */
1254 * Lookup an entry in the scan cache. We assume we're
1255 * called from the bottom half or such that we don't need
1256 * to block the bottom half so that it's safe to return
1257 * a reference to an entry w/o holding the lock on the table.
1259 static struct sta_entry *
1260 sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN])
1262 struct sta_entry *se;
1263 int hash = STA_HASH(macaddr);
1265 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1266 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
1267 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
1269 lockmgr(&st->st_lock, LK_RELEASE);
1271 return se; /* NB: unlocked */
1275 sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1277 struct ieee80211com *ic = vap->iv_ic;
1278 struct ieee80211_node *ni = vap->iv_bss;
1279 struct sta_table *st = ss->ss_priv;
1280 enum ieee80211_phymode mode;
1281 struct sta_entry *se, *selbs;
1282 uint8_t roamRate, curRate, ucastRate;
1283 int8_t roamRssi, curRssi;
1285 se = sta_lookup(st, ni->ni_macaddr);
1287 /* XXX something is wrong */
1291 mode = ieee80211_chan2mode(ic->ic_bsschan);
1292 roamRate = vap->iv_roamparms[mode].rate;
1293 roamRssi = vap->iv_roamparms[mode].rssi;
1294 ucastRate = vap->iv_txparms[mode].ucastrate;
1295 /* NB: the most up to date rssi is in the node, not the scan cache */
1296 curRssi = ic->ic_node_getrssi(ni);
1297 if (ucastRate == IEEE80211_FIXED_RATE_NONE) {
1298 curRate = ni->ni_txrate;
1299 roamRate &= IEEE80211_RATE_VAL;
1300 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1301 "%s: currssi %d currate %u roamrssi %d roamrate %u\n",
1302 __func__, curRssi, curRate, roamRssi, roamRate);
1304 curRate = roamRate; /* NB: insure compare below fails */
1305 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1306 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi);
1309 * Check if a new ap should be used and switch.
1310 * XXX deauth current ap
1312 if (curRate < roamRate || curRssi < roamRssi) {
1313 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
1315 * Scan cache contents are too old; force a scan now
1316 * if possible so we have current state to make a
1317 * decision with. We don't kick off a bg scan if
1318 * we're using dynamic turbo and boosted or if the
1320 * XXX force immediate switch on scan complete
1322 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) &&
1323 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle))
1324 ieee80211_bg_scan(vap, 0);
1327 se->base.se_rssi = curRssi;
1328 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM);
1329 if (selbs != NULL && selbs != se) {
1330 struct ieee80211_channel *chan;
1332 IEEE80211_DPRINTF(vap,
1333 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG,
1334 "%s: ROAM: curRate %u, roamRate %u, "
1335 "curRssi %d, roamRssi %d\n", __func__,
1336 curRate, roamRate, curRssi, roamRssi);
1338 chan = selbs->base.se_chan;
1339 if (selbs->se_flags & STA_DEMOTE11B)
1340 chan = demote11b(vap, chan);
1341 (void) ieee80211_sta_join(vap, chan, &selbs->base);
1347 * Age entries in the scan cache.
1348 * XXX also do roaming since it's convenient
1351 sta_age(struct ieee80211_scan_state *ss)
1353 struct ieee80211vap *vap = ss->ss_vap;
1357 * If rate control is enabled check periodically to see if
1358 * we should roam from our current connection to one that
1359 * might be better. This only applies when we're operating
1360 * in sta mode and automatic roaming is set.
1362 * XXX repeater station
1363 * XXX do when !bgscan?
1365 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1366 ("wrong mode %u", vap->iv_opmode));
1367 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO &&
1368 (vap->iv_ic->ic_flags & IEEE80211_F_BGSCAN) &&
1369 vap->iv_state >= IEEE80211_S_RUN)
1370 /* XXX vap is implicit */
1371 sta_roam_check(ss, vap);
1375 * Iterate over the entries in the scan cache, invoking
1376 * the callback function on each one.
1379 sta_iterate(struct ieee80211_scan_state *ss,
1380 ieee80211_scan_iter_func *f, void *arg)
1382 struct sta_table *st = ss->ss_priv;
1383 struct sta_entry *se;
1386 lockmgr(&st->st_scanlock, LK_EXCLUSIVE);
1387 gen = st->st_scaniter++;
1389 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1390 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1391 if (se->se_scangen != gen) {
1392 se->se_scangen = gen;
1393 /* update public state */
1394 se->base.se_age = ticks - se->se_lastupdate;
1395 lockmgr(&st->st_lock, LK_RELEASE);
1396 (*f)(arg, &se->base);
1400 lockmgr(&st->st_lock, LK_RELEASE);
1402 lockmgr(&st->st_scanlock, LK_RELEASE);
1406 sta_assoc_fail(struct ieee80211_scan_state *ss,
1407 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason)
1409 struct sta_table *st = ss->ss_priv;
1410 struct sta_entry *se;
1412 se = sta_lookup(st, macaddr);
1415 se->se_lastfail = ticks;
1416 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1417 macaddr, "%s: reason %u fails %u",
1418 __func__, reason, se->se_fails);
1423 sta_assoc_success(struct ieee80211_scan_state *ss,
1424 const uint8_t macaddr[IEEE80211_ADDR_LEN])
1426 struct sta_table *st = ss->ss_priv;
1427 struct sta_entry *se;
1429 se = sta_lookup(st, macaddr);
1433 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1434 macaddr, "%s: fails %u",
1435 __func__, se->se_fails);
1437 se->se_lastassoc = ticks;
1441 static const struct ieee80211_scanner sta_default = {
1442 .scan_name = "default",
1443 .scan_attach = sta_attach,
1444 .scan_detach = sta_detach,
1445 .scan_start = sta_start,
1446 .scan_restart = sta_restart,
1447 .scan_cancel = sta_cancel,
1448 .scan_end = sta_pick_bss,
1449 .scan_flush = sta_flush,
1450 .scan_add = sta_add,
1451 .scan_age = sta_age,
1452 .scan_iterate = sta_iterate,
1453 .scan_assoc_fail = sta_assoc_fail,
1454 .scan_assoc_success = sta_assoc_success,
1456 IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default);
1459 * Adhoc mode-specific support.
1462 static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */
1463 { 5180, 5200, 5220, 5240 };
1464 static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */
1465 { 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 };
1466 static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */
1467 { 5170, 5190, 5210, 5230 };
1468 static const uint16_t adhoc11b[] = /* 10, 11 */
1471 static const struct scanlist adhocScanTable[] = {
1472 { IEEE80211_MODE_11B, X(adhoc11b) },
1473 { IEEE80211_MODE_11A, X(adhocWorld) },
1474 { IEEE80211_MODE_11A, X(adhocFcc3) },
1475 { IEEE80211_MODE_11B, X(adhocMkk) },
1481 * Start an adhoc-mode scan by populating the channel list.
1484 adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1486 struct sta_table *st = ss->ss_priv;
1488 makescanlist(ss, vap, adhocScanTable);
1490 if (ss->ss_mindwell == 0)
1491 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1492 if (ss->ss_maxdwell == 0)
1493 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1502 * Select a channel to start an adhoc network on.
1503 * The channel list was populated with appropriate
1504 * channels so select one that looks least occupied.
1506 static struct ieee80211_channel *
1507 adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags)
1509 struct sta_table *st = ss->ss_priv;
1510 struct sta_entry *se;
1511 struct ieee80211_channel *c, *bestchan;
1512 int i, bestrssi, maxrssi;
1517 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1518 for (i = 0; i < ss->ss_last; i++) {
1519 c = ss->ss_chans[i];
1520 /* never consider a channel with radar */
1521 if (IEEE80211_IS_CHAN_RADAR(c))
1523 /* skip channels disallowed by regulatory settings */
1524 if (IEEE80211_IS_CHAN_NOADHOC(c))
1526 /* check channel attributes for band compatibility */
1527 if (flags != 0 && (c->ic_flags & flags) != flags)
1530 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1531 if (se->base.se_chan != c)
1533 if (se->base.se_rssi > maxrssi)
1534 maxrssi = se->base.se_rssi;
1536 if (bestchan == NULL || maxrssi < bestrssi)
1539 lockmgr(&st->st_lock, LK_RELEASE);
1545 * Pick an ibss network to join or find a channel
1546 * to use to start an ibss network.
1549 adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1551 struct sta_table *st = ss->ss_priv;
1552 struct sta_entry *selbs;
1553 struct ieee80211_channel *chan;
1555 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS ||
1556 vap->iv_opmode == IEEE80211_M_AHDEMO ||
1557 vap->iv_opmode == IEEE80211_M_MBSS,
1558 ("wrong opmode %u", vap->iv_opmode));
1560 if (st->st_newscan) {
1561 sta_update_notseen(st);
1564 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1566 * Manual/background scan, don't select+join the
1567 * bss, just return. The scanning framework will
1568 * handle notification that this has completed.
1570 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1574 * Automatic sequencing; look for a candidate and
1575 * if found join the network.
1577 /* NB: unlocked read should be ok */
1578 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1579 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1580 "%s: no scan candidate\n", __func__);
1581 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1584 /* NB: never auto-start a tdma network for slot !0 */
1585 #ifdef IEEE80211_SUPPORT_TDMA
1586 if (vap->iv_des_nssid &&
1587 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 ||
1588 ieee80211_tdma_getslot(vap) == 0)) {
1590 if (vap->iv_des_nssid) {
1593 * No existing adhoc network to join and we have
1594 * an ssid; start one up. If no channel was
1595 * specified, try to select a channel.
1597 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC ||
1598 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
1599 struct ieee80211com *ic = vap->iv_ic;
1601 chan = adhoc_pick_channel(ss, 0);
1603 chan = ieee80211_ht_adjust_channel(ic,
1604 chan, vap->iv_flags_ht);
1606 chan = vap->iv_des_chan;
1608 ieee80211_create_ibss(vap, chan);
1613 * If nothing suitable was found decrement
1614 * the failure counts so entries will be
1615 * reconsidered the next time around. We
1616 * really want to do this only for sta's
1617 * where we've previously had some success.
1621 return 0; /* restart scan */
1623 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1624 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1625 return (selbs != NULL);
1628 chan = selbs->base.se_chan;
1629 if (selbs->se_flags & STA_DEMOTE11B)
1630 chan = demote11b(vap, chan);
1631 if (!ieee80211_sta_join(vap, chan, &selbs->base))
1633 return 1; /* terminate scan */
1637 * Age entries in the scan cache.
1640 adhoc_age(struct ieee80211_scan_state *ss)
1642 struct sta_table *st = ss->ss_priv;
1643 struct sta_entry *se, *next;
1645 lockmgr(&st->st_lock, LK_EXCLUSIVE);
1646 TAILQ_FOREACH_MUTABLE(se, &st->st_entry, se_list, next) {
1647 if (se->se_notseen > STA_PURGE_SCANS) {
1648 TAILQ_REMOVE(&st->st_entry, se, se_list);
1649 LIST_REMOVE(se, se_hash);
1650 ieee80211_ies_cleanup(&se->base.se_ies);
1651 kfree(se, M_80211_SCAN);
1654 lockmgr(&st->st_lock, LK_RELEASE);
1657 static const struct ieee80211_scanner adhoc_default = {
1658 .scan_name = "default",
1659 .scan_attach = sta_attach,
1660 .scan_detach = sta_detach,
1661 .scan_start = adhoc_start,
1662 .scan_restart = sta_restart,
1663 .scan_cancel = sta_cancel,
1664 .scan_end = adhoc_pick_bss,
1665 .scan_flush = sta_flush,
1666 .scan_pickchan = adhoc_pick_channel,
1667 .scan_add = sta_add,
1668 .scan_age = adhoc_age,
1669 .scan_iterate = sta_iterate,
1670 .scan_assoc_fail = sta_assoc_fail,
1671 .scan_assoc_success = sta_assoc_success,
1673 IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default);
1674 IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default);
1677 ap_force_promisc(struct ieee80211com *ic)
1679 struct ifnet *ifp = ic->ic_ifp;
1681 /* set interface into promiscuous mode */
1682 ifp->if_flags |= IFF_PROMISC;
1683 ieee80211_runtask(ic, &ic->ic_promisc_task);
1687 ap_reset_promisc(struct ieee80211com *ic)
1689 ieee80211_syncifflag_locked(ic, IFF_PROMISC);
1693 ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1695 struct sta_table *st = ss->ss_priv;
1697 makescanlist(ss, vap, staScanTable);
1699 if (ss->ss_mindwell == 0)
1700 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1701 if (ss->ss_maxdwell == 0)
1702 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1707 ap_force_promisc(vap->iv_ic);
1712 * Cancel an ongoing scan.
1715 ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1717 ap_reset_promisc(vap->iv_ic);
1722 * Pick a quiet channel to use for ap operation.
1724 static struct ieee80211_channel *
1725 ap_pick_channel(struct ieee80211_scan_state *ss, int flags)
1727 struct sta_table *st = ss->ss_priv;
1728 struct ieee80211_channel *bestchan = NULL;
1731 /* XXX select channel more intelligently, e.g. channel spread, power */
1732 /* NB: use scan list order to preserve channel preference */
1733 for (i = 0; i < ss->ss_last; i++) {
1734 struct ieee80211_channel *chan = ss->ss_chans[i];
1736 * If the channel is unoccupied the max rssi
1737 * should be zero; just take it. Otherwise
1738 * track the channel with the lowest rssi and
1739 * use that when all channels appear occupied.
1741 if (IEEE80211_IS_CHAN_RADAR(chan))
1743 if (IEEE80211_IS_CHAN_NOHOSTAP(chan))
1745 /* check channel attributes for band compatibility */
1746 if (flags != 0 && (chan->ic_flags & flags) != flags)
1748 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size"));
1749 /* XXX channel have interference */
1750 if (st->st_maxrssi[chan->ic_ieee] == 0) {
1751 /* XXX use other considerations */
1754 if (bestchan == NULL ||
1755 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee])
1762 * Pick a quiet channel to use for ap operation.
1765 ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1767 struct ieee80211com *ic = vap->iv_ic;
1768 struct ieee80211_channel *bestchan;
1770 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP,
1771 ("wrong opmode %u", vap->iv_opmode));
1772 bestchan = ap_pick_channel(ss, 0);
1773 if (bestchan == NULL) {
1774 /* no suitable channel, should not happen */
1775 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1776 "%s: no suitable channel! (should not happen)\n", __func__);
1777 /* XXX print something? */
1778 return 0; /* restart scan */
1781 * If this is a dynamic turbo channel, start with the unboosted one.
1783 if (IEEE80211_IS_CHAN_TURBO(bestchan)) {
1784 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq,
1785 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO);
1786 if (bestchan == NULL) {
1787 /* should never happen ?? */
1791 ap_reset_promisc(ic);
1792 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) {
1794 * Manual/background scan, don't select+join the
1795 * bss, just return. The scanning framework will
1796 * handle notification that this has completed.
1798 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1801 ieee80211_create_ibss(vap,
1802 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht));
1806 static const struct ieee80211_scanner ap_default = {
1807 .scan_name = "default",
1808 .scan_attach = sta_attach,
1809 .scan_detach = sta_detach,
1810 .scan_start = ap_start,
1811 .scan_restart = sta_restart,
1812 .scan_cancel = ap_cancel,
1814 .scan_flush = sta_flush,
1815 .scan_pickchan = ap_pick_channel,
1816 .scan_add = sta_add,
1817 .scan_age = adhoc_age,
1818 .scan_iterate = sta_iterate,
1819 .scan_assoc_success = sta_assoc_success,
1820 .scan_assoc_fail = sta_assoc_fail,
1822 IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default);
1824 #ifdef IEEE80211_SUPPORT_MESH
1826 * Pick an mbss network to join or find a channel
1827 * to use to start an mbss network.
1830 mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1832 struct sta_table *st = ss->ss_priv;
1833 struct ieee80211_mesh_state *ms = vap->iv_mesh;
1834 struct sta_entry *selbs;
1835 struct ieee80211_channel *chan;
1837 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS,
1838 ("wrong opmode %u", vap->iv_opmode));
1840 if (st->st_newscan) {
1841 sta_update_notseen(st);
1844 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1846 * Manual/background scan, don't select+join the
1847 * bss, just return. The scanning framework will
1848 * handle notification that this has completed.
1850 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1854 * Automatic sequencing; look for a candidate and
1855 * if found join the network.
1857 /* NB: unlocked read should be ok */
1858 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1859 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1860 "%s: no scan candidate\n", __func__);
1861 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1864 if (ms->ms_idlen != 0) {
1866 * No existing mbss network to join and we have
1867 * a meshid; start one up. If no channel was
1868 * specified, try to select a channel.
1870 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC ||
1871 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
1872 struct ieee80211com *ic = vap->iv_ic;
1874 chan = adhoc_pick_channel(ss, 0);
1876 chan = ieee80211_ht_adjust_channel(ic,
1877 chan, vap->iv_flags_ht);
1879 chan = vap->iv_des_chan;
1881 ieee80211_create_ibss(vap, chan);
1886 * If nothing suitable was found decrement
1887 * the failure counts so entries will be
1888 * reconsidered the next time around. We
1889 * really want to do this only for sta's
1890 * where we've previously had some success.
1894 return 0; /* restart scan */
1896 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1897 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1898 return (selbs != NULL);
1901 chan = selbs->base.se_chan;
1902 if (selbs->se_flags & STA_DEMOTE11B)
1903 chan = demote11b(vap, chan);
1904 if (!ieee80211_sta_join(vap, chan, &selbs->base))
1906 return 1; /* terminate scan */
1909 static const struct ieee80211_scanner mesh_default = {
1910 .scan_name = "default",
1911 .scan_attach = sta_attach,
1912 .scan_detach = sta_detach,
1913 .scan_start = adhoc_start,
1914 .scan_restart = sta_restart,
1915 .scan_cancel = sta_cancel,
1916 .scan_end = mesh_pick_bss,
1917 .scan_flush = sta_flush,
1918 .scan_pickchan = adhoc_pick_channel,
1919 .scan_add = sta_add,
1920 .scan_age = adhoc_age,
1921 .scan_iterate = sta_iterate,
1922 .scan_assoc_fail = sta_assoc_fail,
1923 .scan_assoc_success = sta_assoc_success,
1925 IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default);
1926 #endif /* IEEE80211_SUPPORT_MESH */