2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
32 * IEEE 802.11 scanning support.
36 #include <sys/param.h>
37 #include <sys/systm.h>
39 #include <sys/kernel.h>
40 #include <sys/malloc.h>
41 #include <sys/condvar.h>
43 #include <sys/socket.h>
46 #include <net/if_var.h>
47 #include <net/if_media.h>
48 #include <net/ethernet.h>
50 #include <net80211/ieee80211_var.h>
52 /* XXX until it's implemented as attach ops */
53 #include <net80211/ieee80211_scan_sw.h>
58 * Roaming-related defaults. RSSI thresholds are as returned by the
59 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
63 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
64 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
65 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
66 /* transmit rate thresholds */
67 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
68 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
69 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
70 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
71 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
72 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
73 #define ROAM_MCS_11AC_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
76 ieee80211_scan_attach(struct ieee80211com *ic)
79 * If there's no scan method pointer, attach the
80 * swscan set as a default.
82 if (ic->ic_scan_methods == NULL)
83 ieee80211_swscan_attach(ic);
85 ic->ic_scan_methods->sc_attach(ic);
89 ieee80211_scan_detach(struct ieee80211com *ic)
93 * Ideally we'd do the ss_ops detach call here;
94 * but then sc_detach() would need to be split in two.
98 ic->ic_scan_methods->sc_detach(ic);
101 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
102 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
103 .rate = ROAM_RATE_11A_DEFAULT },
104 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
105 .rate = ROAM_RATE_11B_DEFAULT },
106 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
107 .rate = ROAM_RATE_11BONLY_DEFAULT },
108 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
109 .rate = ROAM_RATE_11A_DEFAULT },
110 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
111 .rate = ROAM_RATE_11A_DEFAULT },
112 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
113 .rate = ROAM_RATE_11A_DEFAULT },
114 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
115 .rate = ROAM_RATE_HALF_DEFAULT },
116 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
117 .rate = ROAM_RATE_QUARTER_DEFAULT },
118 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
119 .rate = ROAM_MCS_11N_DEFAULT },
120 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
121 .rate = ROAM_MCS_11N_DEFAULT },
122 [IEEE80211_MODE_VHT_2GHZ] = { .rssi = ROAM_RSSI_11B_DEFAULT,
123 .rate = ROAM_MCS_11AC_DEFAULT },
124 [IEEE80211_MODE_VHT_5GHZ] = { .rssi = ROAM_RSSI_11A_DEFAULT,
125 .rate = ROAM_MCS_11AC_DEFAULT },
130 ieee80211_scan_vattach(struct ieee80211vap *vap)
132 struct ieee80211com *ic = vap->iv_ic;
135 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
136 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
137 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
139 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
141 memset(vap->iv_roamparms, 0, sizeof(vap->iv_roamparms));
142 for (m = IEEE80211_MODE_AUTO + 1; m < IEEE80211_MODE_MAX; m++) {
143 if (isclr(ic->ic_modecaps, m))
146 memcpy(&vap->iv_roamparms[m], &defroam[m], sizeof(defroam[m]));
149 ic->ic_scan_methods->sc_vattach(vap);
153 ieee80211_scan_vdetach(struct ieee80211vap *vap)
155 struct ieee80211com *ic = vap->iv_ic;
156 struct ieee80211_scan_state *ss;
161 ic->ic_scan_methods->sc_vdetach(vap);
163 if (ss != NULL && ss->ss_vap == vap) {
164 if (ss->ss_ops != NULL) {
165 ss->ss_ops->scan_detach(ss);
170 IEEE80211_UNLOCK(ic);
174 * Simple-minded scanner module support.
176 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
177 "wlan_scan_sta", /* IEEE80211_M_IBSS */
178 "wlan_scan_sta", /* IEEE80211_M_STA */
179 "wlan_scan_wds", /* IEEE80211_M_WDS */
180 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
181 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
182 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
183 "wlan_scan_sta", /* IEEE80211_M_MBSS */
185 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
187 const struct ieee80211_scanner *
188 ieee80211_scanner_get(enum ieee80211_opmode mode)
190 if (mode >= IEEE80211_OPMODE_MAX)
192 if (scanners[mode] == NULL)
193 ieee80211_load_module(scan_modnames[mode]);
194 return scanners[mode];
198 ieee80211_scanner_register(enum ieee80211_opmode mode,
199 const struct ieee80211_scanner *scan)
201 if (mode >= IEEE80211_OPMODE_MAX)
203 scanners[mode] = scan;
207 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
208 const struct ieee80211_scanner *scan)
210 if (mode >= IEEE80211_OPMODE_MAX)
212 if (scanners[mode] == scan)
213 scanners[mode] = NULL;
217 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
221 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
222 if (scanners[m] == scan)
227 * Update common scanner state to reflect the current
228 * operating mode. This is called when the state machine
229 * is transitioned to RUN state w/o scanning--e.g. when
230 * operating in monitor mode. The purpose of this is to
231 * ensure later callbacks find ss_ops set to properly
232 * reflect current operating mode.
235 ieee80211_scan_update_locked(struct ieee80211vap *vap,
236 const struct ieee80211_scanner *scan)
238 struct ieee80211com *ic = vap->iv_ic;
239 struct ieee80211_scan_state *ss = ic->ic_scan;
241 IEEE80211_LOCK_ASSERT(ic);
243 #ifdef IEEE80211_DEBUG
244 if (ss->ss_vap != vap || ss->ss_ops != scan) {
245 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
246 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
249 ss->ss_vap->iv_ifp->if_xname : "none",
251 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
252 vap->iv_ifp->if_xname,
253 ieee80211_opmode_name[vap->iv_opmode]);
257 if (ss->ss_ops != scan) {
259 * Switch scanners; detach old, attach new. Special
260 * case where a single scan module implements multiple
261 * policies by using different scan ops but a common
262 * core. We assume if the old and new attach methods
263 * are identical then it's ok to just change ss_ops
264 * and not flush the internal state of the module.
266 if (scan == NULL || ss->ss_ops == NULL ||
267 ss->ss_ops->scan_attach != scan->scan_attach) {
268 if (ss->ss_ops != NULL)
269 ss->ss_ops->scan_detach(ss);
270 if (scan != NULL && !scan->scan_attach(ss)) {
271 /* XXX attach failure */
281 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
283 struct ieee80211com *ic = ss->ss_ic;
288 for (i = ss->ss_next; i < ss->ss_last; i++) {
289 const struct ieee80211_channel *c = ss->ss_chans[i];
291 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
292 ieee80211_channel_type_char(c));
297 #ifdef IEEE80211_DEBUG
299 ieee80211_scan_dump(struct ieee80211_scan_state *ss)
301 struct ieee80211vap *vap = ss->ss_vap;
303 if_printf(vap->iv_ifp, "scan set ");
304 ieee80211_scan_dump_channels(ss);
305 printf(" dwell min %ums max %ums\n",
306 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
308 #endif /* IEEE80211_DEBUG */
311 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
312 int nssid, const struct ieee80211_scan_ssid ssids[])
314 if (nssid > IEEE80211_SCAN_MAX_SSID) {
316 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
317 "%s: too many ssid %d, ignoring all of them\n",
321 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
322 ss->ss_nssid = nssid;
326 * Start a scan unless one is already going.
329 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
330 u_int duration, u_int mindwell, u_int maxdwell,
331 u_int nssid, const struct ieee80211_scan_ssid ssids[])
333 const struct ieee80211_scanner *scan;
334 struct ieee80211com *ic = vap->iv_ic;
336 scan = ieee80211_scanner_get(vap->iv_opmode);
338 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
339 "%s: no scanner support for %s mode\n",
340 __func__, ieee80211_opmode_name[vap->iv_opmode]);
345 return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
346 mindwell, maxdwell, nssid, ssids);
350 * Check the scan cache for an ap/channel to use; if that
351 * fails then kick off a new scan.
354 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
355 u_int duration, u_int mindwell, u_int maxdwell,
356 u_int nssid, const struct ieee80211_scan_ssid ssids[])
358 struct ieee80211com *ic = vap->iv_ic;
359 struct ieee80211_scan_state *ss = ic->ic_scan;
360 const struct ieee80211_scanner *scan;
363 scan = ieee80211_scanner_get(vap->iv_opmode);
365 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
366 "%s: no scanner support for %s mode\n",
367 __func__, vap->iv_opmode);
373 * Check if there's a list of scan candidates already.
374 * XXX want more than the ap we're currently associated with
378 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
379 "%s: %s scan, %s%s%s%s%s\n"
381 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
382 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
383 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
384 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
385 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
386 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
389 if (ss->ss_ops != scan) {
390 /* XXX re-use cache contents? e.g. adhoc<->sta */
391 flags |= IEEE80211_SCAN_FLUSH;
395 * XXX TODO: separate things out a bit better.
397 ieee80211_scan_update_locked(vap, scan);
399 result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
400 mindwell, maxdwell, nssid, ssids);
402 IEEE80211_UNLOCK(ic);
408 * Check the scan cache for an ap/channel to use; if that fails
409 * then kick off a scan using the current settings.
412 ieee80211_check_scan_current(struct ieee80211vap *vap)
414 return ieee80211_check_scan(vap,
415 IEEE80211_SCAN_ACTIVE,
416 IEEE80211_SCAN_FOREVER, 0, 0,
417 vap->iv_des_nssid, vap->iv_des_ssid);
421 * Restart a previous scan. If the previous scan completed
422 * then we start again using the existing channel list.
425 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
427 struct ieee80211com *ic = vap->iv_ic;
428 const struct ieee80211_scanner *scan;
430 // IEEE80211_UNLOCK_ASSERT(sc);
432 scan = ieee80211_scanner_get(vap->iv_opmode);
434 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
435 "%s: no scanner support for %s mode\n",
436 __func__, vap->iv_opmode);
442 * XXX TODO: pull apart the bgscan logic into whatever
443 * belongs here and whatever belongs in the software
446 return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
450 * Cancel any scan currently going on for the specified vap.
453 ieee80211_cancel_scan(struct ieee80211vap *vap)
455 struct ieee80211com *ic = vap->iv_ic;
457 ic->ic_scan_methods->sc_cancel_scan(vap);
461 * Cancel any scan currently going on.
463 * This is called during normal 802.11 data path to cancel
464 * a scan so a newly arrived normal data packet can be sent.
467 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
469 struct ieee80211com *ic = vap->iv_ic;
471 ic->ic_scan_methods->sc_cancel_anyscan(vap);
475 * Manually switch to the next channel in the channel list.
476 * Provided for drivers that manage scanning themselves
477 * (e.g. for firmware-based devices).
480 ieee80211_scan_next(struct ieee80211vap *vap)
482 struct ieee80211com *ic = vap->iv_ic;
484 ic->ic_scan_methods->sc_scan_next(vap);
488 * Manually stop a scan that is currently running.
489 * Provided for drivers that are not able to scan single channels
490 * (e.g. for firmware-based devices).
493 ieee80211_scan_done(struct ieee80211vap *vap)
495 struct ieee80211com *ic = vap->iv_ic;
496 struct ieee80211_scan_state *ss;
498 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
502 ss->ss_next = ss->ss_last; /* all channels are complete */
504 ic->ic_scan_methods->sc_scan_done(vap);
506 IEEE80211_UNLOCK(ic);
510 * Probe the current channel, if allowed, while scanning.
511 * If the channel is not marked passive-only then send
512 * a probe request immediately. Otherwise mark state and
513 * listen for beacons on the channel; if we receive something
514 * then we'll transmit a probe request.
517 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
519 struct ieee80211com *ic = vap->iv_ic;
521 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
522 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
526 ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
529 #ifdef IEEE80211_DEBUG
531 dump_country(const uint8_t *ie)
533 const struct ieee80211_country_ie *cie =
534 (const struct ieee80211_country_ie *) ie;
535 int i, nbands, schan, nchan;
538 printf(" <bogus country ie, len %d>", cie->len);
541 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
542 nbands = (cie->len - 3) / sizeof(cie->band[0]);
543 for (i = 0; i < nbands; i++) {
544 schan = cie->band[i].schan;
545 nchan = cie->band[i].nchan;
547 printf(" %u-%u,%u", schan, schan + nchan-1,
548 cie->band[i].maxtxpwr);
550 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
556 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
557 const uint8_t mac[IEEE80211_ADDR_LEN],
558 const struct ieee80211_scanparams *sp, int rssi)
561 printf("[%s] %s%s on chan %u (bss chan %u) ",
562 ether_sprintf(mac), isnew ? "new " : "",
563 ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
564 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
565 printf(" rssi %d\n", rssi);
568 printf("[%s] caps 0x%x bintval %u erp 0x%x",
569 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
570 if (sp->country != NULL)
571 dump_country(sp->country);
575 #endif /* IEEE80211_DEBUG */
578 * Process a beacon or probe response frame.
581 ieee80211_add_scan(struct ieee80211vap *vap,
582 struct ieee80211_channel *curchan,
583 const struct ieee80211_scanparams *sp,
584 const struct ieee80211_frame *wh,
585 int subtype, int rssi, int noise)
587 struct ieee80211com *ic = vap->iv_ic;
589 return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
594 * Timeout/age scan cache entries; called from sta timeout
595 * timer (XXX should be self-contained).
598 ieee80211_scan_timeout(struct ieee80211com *ic)
600 struct ieee80211_scan_state *ss = ic->ic_scan;
602 if (ss->ss_ops != NULL)
603 ss->ss_ops->scan_age(ss);
607 * Mark a scan cache entry after a successful associate.
610 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
612 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
614 if (ss->ss_ops != NULL) {
615 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
616 mac, "%s", __func__);
617 ss->ss_ops->scan_assoc_success(ss, mac);
622 * Demerit a scan cache entry after failing to associate.
625 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
626 const uint8_t mac[], int reason)
628 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
630 if (ss->ss_ops != NULL) {
631 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
632 "%s: reason %u", __func__, reason);
633 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
638 * Iterate over the contents of the scan cache.
641 ieee80211_scan_iterate(struct ieee80211vap *vap,
642 ieee80211_scan_iter_func *f, void *arg)
644 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
646 if (ss->ss_ops != NULL)
647 ss->ss_ops->scan_iterate(ss, f, arg);
651 * Flush the contents of the scan cache.
654 ieee80211_scan_flush(struct ieee80211vap *vap)
656 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
658 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
659 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
660 ss->ss_ops->scan_flush(ss);
665 * Check the scan cache for an ap/channel to use; if that
666 * fails then kick off a new scan.
668 struct ieee80211_channel *
669 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
671 struct ieee80211_scan_state *ss = ic->ic_scan;
673 IEEE80211_LOCK_ASSERT(ic);
675 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
679 if (ss->ss_ops->scan_pickchan == NULL) {
680 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
681 "%s: scan module does not support picking a channel, "
682 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
685 return ss->ss_ops->scan_pickchan(ss, flags);