2 * Copyright (c) 2002-2008 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.
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
30 * IEEE 802.11 scanning support.
34 #include <sys/param.h>
35 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/malloc.h>
39 #include <sys/condvar.h>
41 #include <sys/socket.h>
44 #include <net/if_var.h>
45 #include <net/if_media.h>
46 #include <net/ethernet.h>
48 #include <net80211/ieee80211_var.h>
50 /* XXX until it's implemented as attach ops */
51 #include <net80211/ieee80211_scan_sw.h>
56 * Roaming-related defaults. RSSI thresholds are as returned by the
57 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
61 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
62 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
63 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
64 /* transmit rate thresholds */
65 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
66 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
67 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
68 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
69 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
70 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
71 #define ROAM_MCS_11AC_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
74 ieee80211_scan_attach(struct ieee80211com *ic)
77 * If there's no scan method pointer, attach the
78 * swscan set as a default.
80 if (ic->ic_scan_methods == NULL)
81 ieee80211_swscan_attach(ic);
83 ic->ic_scan_methods->sc_attach(ic);
87 ieee80211_scan_detach(struct ieee80211com *ic)
91 * Ideally we'd do the ss_ops detach call here;
92 * but then sc_detach() would need to be split in two.
96 ic->ic_scan_methods->sc_detach(ic);
99 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
100 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
101 .rate = ROAM_RATE_11A_DEFAULT },
102 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
103 .rate = ROAM_RATE_11B_DEFAULT },
104 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
105 .rate = ROAM_RATE_11BONLY_DEFAULT },
106 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
107 .rate = ROAM_RATE_11A_DEFAULT },
108 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
109 .rate = ROAM_RATE_11A_DEFAULT },
110 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
111 .rate = ROAM_RATE_11A_DEFAULT },
112 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
113 .rate = ROAM_RATE_HALF_DEFAULT },
114 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
115 .rate = ROAM_RATE_QUARTER_DEFAULT },
116 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
117 .rate = ROAM_MCS_11N_DEFAULT },
118 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
119 .rate = ROAM_MCS_11N_DEFAULT },
120 [IEEE80211_MODE_VHT_2GHZ] = { .rssi = ROAM_RSSI_11B_DEFAULT,
121 .rate = ROAM_MCS_11AC_DEFAULT },
122 [IEEE80211_MODE_VHT_5GHZ] = { .rssi = ROAM_RSSI_11A_DEFAULT,
123 .rate = ROAM_MCS_11AC_DEFAULT },
128 ieee80211_scan_vattach(struct ieee80211vap *vap)
130 struct ieee80211com *ic = vap->iv_ic;
132 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
133 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
134 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
136 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
137 memcpy(vap->iv_roamparms, defroam, sizeof(defroam));
139 ic->ic_scan_methods->sc_vattach(vap);
143 ieee80211_scan_vdetach(struct ieee80211vap *vap)
145 struct ieee80211com *ic = vap->iv_ic;
146 struct ieee80211_scan_state *ss;
151 ic->ic_scan_methods->sc_vdetach(vap);
153 if (ss != NULL && ss->ss_vap == vap) {
154 if (ss->ss_ops != NULL) {
155 ss->ss_ops->scan_detach(ss);
160 IEEE80211_UNLOCK(ic);
164 * Simple-minded scanner module support.
166 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
167 "wlan_scan_sta", /* IEEE80211_M_IBSS */
168 "wlan_scan_sta", /* IEEE80211_M_STA */
169 "wlan_scan_wds", /* IEEE80211_M_WDS */
170 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
171 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
172 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
173 "wlan_scan_sta", /* IEEE80211_M_MBSS */
175 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
177 const struct ieee80211_scanner *
178 ieee80211_scanner_get(enum ieee80211_opmode mode)
180 if (mode >= IEEE80211_OPMODE_MAX)
182 if (scanners[mode] == NULL)
183 ieee80211_load_module(scan_modnames[mode]);
184 return scanners[mode];
188 ieee80211_scanner_register(enum ieee80211_opmode mode,
189 const struct ieee80211_scanner *scan)
191 if (mode >= IEEE80211_OPMODE_MAX)
193 scanners[mode] = scan;
197 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
198 const struct ieee80211_scanner *scan)
200 if (mode >= IEEE80211_OPMODE_MAX)
202 if (scanners[mode] == scan)
203 scanners[mode] = NULL;
207 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
211 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
212 if (scanners[m] == scan)
217 * Update common scanner state to reflect the current
218 * operating mode. This is called when the state machine
219 * is transitioned to RUN state w/o scanning--e.g. when
220 * operating in monitor mode. The purpose of this is to
221 * ensure later callbacks find ss_ops set to properly
222 * reflect current operating mode.
225 ieee80211_scan_update_locked(struct ieee80211vap *vap,
226 const struct ieee80211_scanner *scan)
228 struct ieee80211com *ic = vap->iv_ic;
229 struct ieee80211_scan_state *ss = ic->ic_scan;
231 IEEE80211_LOCK_ASSERT(ic);
233 #ifdef IEEE80211_DEBUG
234 if (ss->ss_vap != vap || ss->ss_ops != scan) {
235 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
236 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
239 ss->ss_vap->iv_ifp->if_xname : "none",
241 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
242 vap->iv_ifp->if_xname,
243 ieee80211_opmode_name[vap->iv_opmode]);
247 if (ss->ss_ops != scan) {
249 * Switch scanners; detach old, attach new. Special
250 * case where a single scan module implements multiple
251 * policies by using different scan ops but a common
252 * core. We assume if the old and new attach methods
253 * are identical then it's ok to just change ss_ops
254 * and not flush the internal state of the module.
256 if (scan == NULL || ss->ss_ops == NULL ||
257 ss->ss_ops->scan_attach != scan->scan_attach) {
258 if (ss->ss_ops != NULL)
259 ss->ss_ops->scan_detach(ss);
260 if (scan != NULL && !scan->scan_attach(ss)) {
261 /* XXX attach failure */
271 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
273 struct ieee80211com *ic = ss->ss_ic;
278 for (i = ss->ss_next; i < ss->ss_last; i++) {
279 const struct ieee80211_channel *c = ss->ss_chans[i];
281 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
282 ieee80211_channel_type_char(c));
287 #ifdef IEEE80211_DEBUG
289 ieee80211_scan_dump(struct ieee80211_scan_state *ss)
291 struct ieee80211vap *vap = ss->ss_vap;
293 if_printf(vap->iv_ifp, "scan set ");
294 ieee80211_scan_dump_channels(ss);
295 printf(" dwell min %lums max %lums\n",
296 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
298 #endif /* IEEE80211_DEBUG */
301 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
302 int nssid, const struct ieee80211_scan_ssid ssids[])
304 if (nssid > IEEE80211_SCAN_MAX_SSID) {
306 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
307 "%s: too many ssid %d, ignoring all of them\n",
311 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
312 ss->ss_nssid = nssid;
316 * Start a scan unless one is already going.
319 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
320 u_int duration, u_int mindwell, u_int maxdwell,
321 u_int nssid, const struct ieee80211_scan_ssid ssids[])
323 const struct ieee80211_scanner *scan;
324 struct ieee80211com *ic = vap->iv_ic;
326 scan = ieee80211_scanner_get(vap->iv_opmode);
328 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
329 "%s: no scanner support for %s mode\n",
330 __func__, ieee80211_opmode_name[vap->iv_opmode]);
335 return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
336 mindwell, maxdwell, nssid, ssids);
340 * Check the scan cache for an ap/channel to use; if that
341 * fails then kick off a new scan.
344 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
345 u_int duration, u_int mindwell, u_int maxdwell,
346 u_int nssid, const struct ieee80211_scan_ssid ssids[])
348 struct ieee80211com *ic = vap->iv_ic;
349 struct ieee80211_scan_state *ss = ic->ic_scan;
350 const struct ieee80211_scanner *scan;
353 scan = ieee80211_scanner_get(vap->iv_opmode);
355 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
356 "%s: no scanner support for %s mode\n",
357 __func__, vap->iv_opmode);
363 * Check if there's a list of scan candidates already.
364 * XXX want more than the ap we're currently associated with
368 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
369 "%s: %s scan, %s%s%s%s%s\n"
371 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
372 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
373 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
374 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
375 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
376 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
379 if (ss->ss_ops != scan) {
380 /* XXX re-use cache contents? e.g. adhoc<->sta */
381 flags |= IEEE80211_SCAN_FLUSH;
385 * XXX TODO: separate things out a bit better.
387 ieee80211_scan_update_locked(vap, scan);
389 result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
390 mindwell, maxdwell, nssid, ssids);
392 IEEE80211_UNLOCK(ic);
398 * Check the scan cache for an ap/channel to use; if that fails
399 * then kick off a scan using the current settings.
402 ieee80211_check_scan_current(struct ieee80211vap *vap)
404 return ieee80211_check_scan(vap,
405 IEEE80211_SCAN_ACTIVE,
406 IEEE80211_SCAN_FOREVER, 0, 0,
407 vap->iv_des_nssid, vap->iv_des_ssid);
411 * Restart a previous scan. If the previous scan completed
412 * then we start again using the existing channel list.
415 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
417 struct ieee80211com *ic = vap->iv_ic;
418 const struct ieee80211_scanner *scan;
420 // IEEE80211_UNLOCK_ASSERT(sc);
422 scan = ieee80211_scanner_get(vap->iv_opmode);
424 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
425 "%s: no scanner support for %s mode\n",
426 __func__, vap->iv_opmode);
432 * XXX TODO: pull apart the bgscan logic into whatever
433 * belongs here and whatever belongs in the software
436 return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
440 * Cancel any scan currently going on for the specified vap.
443 ieee80211_cancel_scan(struct ieee80211vap *vap)
445 struct ieee80211com *ic = vap->iv_ic;
447 ic->ic_scan_methods->sc_cancel_scan(vap);
451 * Cancel any scan currently going on.
453 * This is called during normal 802.11 data path to cancel
454 * a scan so a newly arrived normal data packet can be sent.
457 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
459 struct ieee80211com *ic = vap->iv_ic;
461 ic->ic_scan_methods->sc_cancel_anyscan(vap);
465 * Manually switch to the next channel in the channel list.
466 * Provided for drivers that manage scanning themselves
467 * (e.g. for firmware-based devices).
470 ieee80211_scan_next(struct ieee80211vap *vap)
472 struct ieee80211com *ic = vap->iv_ic;
474 ic->ic_scan_methods->sc_scan_next(vap);
478 * Manually stop a scan that is currently running.
479 * Provided for drivers that are not able to scan single channels
480 * (e.g. for firmware-based devices).
483 ieee80211_scan_done(struct ieee80211vap *vap)
485 struct ieee80211com *ic = vap->iv_ic;
486 struct ieee80211_scan_state *ss;
488 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
492 ss->ss_next = ss->ss_last; /* all channels are complete */
494 ic->ic_scan_methods->sc_scan_done(vap);
496 IEEE80211_UNLOCK(ic);
500 * Probe the current channel, if allowed, while scanning.
501 * If the channel is not marked passive-only then send
502 * a probe request immediately. Otherwise mark state and
503 * listen for beacons on the channel; if we receive something
504 * then we'll transmit a probe request.
507 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
509 struct ieee80211com *ic = vap->iv_ic;
511 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
512 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
516 ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
519 #ifdef IEEE80211_DEBUG
521 dump_country(const uint8_t *ie)
523 const struct ieee80211_country_ie *cie =
524 (const struct ieee80211_country_ie *) ie;
525 int i, nbands, schan, nchan;
528 printf(" <bogus country ie, len %d>", cie->len);
531 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
532 nbands = (cie->len - 3) / sizeof(cie->band[0]);
533 for (i = 0; i < nbands; i++) {
534 schan = cie->band[i].schan;
535 nchan = cie->band[i].nchan;
537 printf(" %u-%u,%u", schan, schan + nchan-1,
538 cie->band[i].maxtxpwr);
540 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
546 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
547 const uint8_t mac[IEEE80211_ADDR_LEN],
548 const struct ieee80211_scanparams *sp, int rssi)
551 printf("[%s] %s%s on chan %u (bss chan %u) ",
552 ether_sprintf(mac), isnew ? "new " : "",
553 ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
554 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
555 printf(" rssi %d\n", rssi);
558 printf("[%s] caps 0x%x bintval %u erp 0x%x",
559 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
560 if (sp->country != NULL)
561 dump_country(sp->country);
565 #endif /* IEEE80211_DEBUG */
568 * Process a beacon or probe response frame.
571 ieee80211_add_scan(struct ieee80211vap *vap,
572 struct ieee80211_channel *curchan,
573 const struct ieee80211_scanparams *sp,
574 const struct ieee80211_frame *wh,
575 int subtype, int rssi, int noise)
577 struct ieee80211com *ic = vap->iv_ic;
579 return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
584 * Timeout/age scan cache entries; called from sta timeout
585 * timer (XXX should be self-contained).
588 ieee80211_scan_timeout(struct ieee80211com *ic)
590 struct ieee80211_scan_state *ss = ic->ic_scan;
592 if (ss->ss_ops != NULL)
593 ss->ss_ops->scan_age(ss);
597 * Mark a scan cache entry after a successful associate.
600 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
602 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
604 if (ss->ss_ops != NULL) {
605 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
606 mac, "%s", __func__);
607 ss->ss_ops->scan_assoc_success(ss, mac);
612 * Demerit a scan cache entry after failing to associate.
615 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
616 const uint8_t mac[], int reason)
618 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
620 if (ss->ss_ops != NULL) {
621 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
622 "%s: reason %u", __func__, reason);
623 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
628 * Iterate over the contents of the scan cache.
631 ieee80211_scan_iterate(struct ieee80211vap *vap,
632 ieee80211_scan_iter_func *f, void *arg)
634 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
636 if (ss->ss_ops != NULL)
637 ss->ss_ops->scan_iterate(ss, f, arg);
641 * Flush the contents of the scan cache.
644 ieee80211_scan_flush(struct ieee80211vap *vap)
646 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
648 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
649 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
650 ss->ss_ops->scan_flush(ss);
655 * Check the scan cache for an ap/channel to use; if that
656 * fails then kick off a new scan.
658 struct ieee80211_channel *
659 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
661 struct ieee80211_scan_state *ss = ic->ic_scan;
663 IEEE80211_LOCK_ASSERT(ic);
665 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
669 if (ss->ss_ops->scan_pickchan == NULL) {
670 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
671 "%s: scan module does not support picking a channel, "
672 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
675 return ss->ss_ops->scan_pickchan(ss, flags);