2 * SPDX-License-Identifier: BSD-2-Clause
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/if_private.h>
49 #include <net/ethernet.h>
51 #include <net80211/ieee80211_var.h>
53 /* XXX until it's implemented as attach ops */
54 #include <net80211/ieee80211_scan_sw.h>
59 * Roaming-related defaults. RSSI thresholds are as returned by the
60 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
64 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
65 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
66 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
67 /* transmit rate thresholds */
68 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
69 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
70 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
71 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
72 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
73 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
74 #define ROAM_MCS_11AC_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
77 ieee80211_scan_attach(struct ieee80211com *ic)
80 * If there's no scan method pointer, attach the
81 * swscan set as a default.
83 if (ic->ic_scan_methods == NULL)
84 ieee80211_swscan_attach(ic);
86 ic->ic_scan_methods->sc_attach(ic);
90 ieee80211_scan_detach(struct ieee80211com *ic)
94 * Ideally we'd do the ss_ops detach call here;
95 * but then sc_detach() would need to be split in two.
99 ic->ic_scan_methods->sc_detach(ic);
102 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
103 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
104 .rate = ROAM_RATE_11A_DEFAULT },
105 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
106 .rate = ROAM_RATE_11B_DEFAULT },
107 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
108 .rate = ROAM_RATE_11BONLY_DEFAULT },
109 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
110 .rate = ROAM_RATE_11A_DEFAULT },
111 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
112 .rate = ROAM_RATE_11A_DEFAULT },
113 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
114 .rate = ROAM_RATE_11A_DEFAULT },
115 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
116 .rate = ROAM_RATE_HALF_DEFAULT },
117 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
118 .rate = ROAM_RATE_QUARTER_DEFAULT },
119 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
120 .rate = ROAM_MCS_11N_DEFAULT },
121 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
122 .rate = ROAM_MCS_11N_DEFAULT },
123 [IEEE80211_MODE_VHT_2GHZ] = { .rssi = ROAM_RSSI_11B_DEFAULT,
124 .rate = ROAM_MCS_11AC_DEFAULT },
125 [IEEE80211_MODE_VHT_5GHZ] = { .rssi = ROAM_RSSI_11A_DEFAULT,
126 .rate = ROAM_MCS_11AC_DEFAULT },
131 ieee80211_scan_vattach(struct ieee80211vap *vap)
133 struct ieee80211com *ic = vap->iv_ic;
136 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
137 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
138 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
140 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
142 memset(vap->iv_roamparms, 0, sizeof(vap->iv_roamparms));
143 for (m = IEEE80211_MODE_AUTO + 1; m < IEEE80211_MODE_MAX; m++) {
144 if (isclr(ic->ic_modecaps, m))
147 memcpy(&vap->iv_roamparms[m], &defroam[m], sizeof(defroam[m]));
150 ic->ic_scan_methods->sc_vattach(vap);
154 ieee80211_scan_vdetach(struct ieee80211vap *vap)
156 struct ieee80211com *ic = vap->iv_ic;
157 struct ieee80211_scan_state *ss;
162 ic->ic_scan_methods->sc_vdetach(vap);
164 if (ss != NULL && ss->ss_vap == vap) {
165 if (ss->ss_ops != NULL) {
166 ss->ss_ops->scan_detach(ss);
171 IEEE80211_UNLOCK(ic);
175 * Simple-minded scanner module support.
177 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
178 "wlan_scan_sta", /* IEEE80211_M_IBSS */
179 "wlan_scan_sta", /* IEEE80211_M_STA */
180 "wlan_scan_wds", /* IEEE80211_M_WDS */
181 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
182 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
183 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
184 "wlan_scan_sta", /* IEEE80211_M_MBSS */
186 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
188 const struct ieee80211_scanner *
189 ieee80211_scanner_get(enum ieee80211_opmode mode)
191 if (mode >= IEEE80211_OPMODE_MAX)
193 if (scanners[mode] == NULL)
194 ieee80211_load_module(scan_modnames[mode]);
195 return scanners[mode];
199 ieee80211_scanner_register(enum ieee80211_opmode mode,
200 const struct ieee80211_scanner *scan)
202 if (mode >= IEEE80211_OPMODE_MAX)
204 scanners[mode] = scan;
208 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
209 const struct ieee80211_scanner *scan)
211 if (mode >= IEEE80211_OPMODE_MAX)
213 if (scanners[mode] == scan)
214 scanners[mode] = NULL;
218 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
222 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
223 if (scanners[m] == scan)
228 * Update common scanner state to reflect the current
229 * operating mode. This is called when the state machine
230 * is transitioned to RUN state w/o scanning--e.g. when
231 * operating in monitor mode. The purpose of this is to
232 * ensure later callbacks find ss_ops set to properly
233 * reflect current operating mode.
236 ieee80211_scan_update_locked(struct ieee80211vap *vap,
237 const struct ieee80211_scanner *scan)
239 struct ieee80211com *ic = vap->iv_ic;
240 struct ieee80211_scan_state *ss = ic->ic_scan;
242 IEEE80211_LOCK_ASSERT(ic);
244 #ifdef IEEE80211_DEBUG
245 if (ss->ss_vap != vap || ss->ss_ops != scan) {
246 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
247 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
250 ss->ss_vap->iv_ifp->if_xname : "none",
252 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
253 vap->iv_ifp->if_xname,
254 ieee80211_opmode_name[vap->iv_opmode]);
258 if (ss->ss_ops != scan) {
260 * Switch scanners; detach old, attach new. Special
261 * case where a single scan module implements multiple
262 * policies by using different scan ops but a common
263 * core. We assume if the old and new attach methods
264 * are identical then it's ok to just change ss_ops
265 * and not flush the internal state of the module.
267 if (scan == NULL || ss->ss_ops == NULL ||
268 ss->ss_ops->scan_attach != scan->scan_attach) {
269 if (ss->ss_ops != NULL)
270 ss->ss_ops->scan_detach(ss);
271 if (scan != NULL && !scan->scan_attach(ss)) {
272 /* XXX attach failure */
281 #ifdef IEEE80211_DEBUG
283 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
285 struct ieee80211com *ic = ss->ss_ic;
290 for (i = ss->ss_next; i < ss->ss_last; i++) {
291 const struct ieee80211_channel *c = ss->ss_chans[i];
293 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
294 ieee80211_channel_type_char(c));
300 ieee80211_scan_dump(struct ieee80211_scan_state *ss)
302 struct ieee80211vap *vap = ss->ss_vap;
304 if_printf(vap->iv_ifp, "scan set ");
305 ieee80211_scan_dump_channels(ss);
306 printf(" dwell min %ums max %ums\n",
307 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
309 #endif /* IEEE80211_DEBUG */
312 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
313 int nssid, const struct ieee80211_scan_ssid ssids[])
315 if (nssid > IEEE80211_SCAN_MAX_SSID) {
317 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
318 "%s: too many ssid %d, ignoring all of them\n",
322 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
323 ss->ss_nssid = nssid;
327 * Start a scan unless one is already going.
330 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
331 u_int duration, u_int mindwell, u_int maxdwell,
332 u_int nssid, const struct ieee80211_scan_ssid ssids[])
334 const struct ieee80211_scanner *scan;
335 struct ieee80211com *ic = vap->iv_ic;
337 scan = ieee80211_scanner_get(vap->iv_opmode);
339 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
340 "%s: no scanner support for %s mode\n",
341 __func__, ieee80211_opmode_name[vap->iv_opmode]);
346 return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
347 mindwell, maxdwell, nssid, ssids);
351 * Check the scan cache for an ap/channel to use; if that
352 * fails then kick off a new scan.
355 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
356 u_int duration, u_int mindwell, u_int maxdwell,
357 u_int nssid, const struct ieee80211_scan_ssid ssids[])
359 struct ieee80211com *ic = vap->iv_ic;
360 struct ieee80211_scan_state *ss = ic->ic_scan;
361 const struct ieee80211_scanner *scan;
364 scan = ieee80211_scanner_get(vap->iv_opmode);
366 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
367 "%s: no scanner support for %s mode\n",
368 __func__, vap->iv_opmode);
374 * Check if there's a list of scan candidates already.
375 * XXX want more than the ap we're currently associated with
379 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
380 "%s: %s scan, %s%s%s%s%s\n"
382 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
383 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
384 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
385 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
386 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
387 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
390 if (ss->ss_ops != scan) {
391 /* XXX re-use cache contents? e.g. adhoc<->sta */
392 flags |= IEEE80211_SCAN_FLUSH;
396 * XXX TODO: separate things out a bit better.
398 ieee80211_scan_update_locked(vap, scan);
400 result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
401 mindwell, maxdwell, nssid, ssids);
403 IEEE80211_UNLOCK(ic);
409 * Check the scan cache for an ap/channel to use; if that fails
410 * then kick off a scan using the current settings.
413 ieee80211_check_scan_current(struct ieee80211vap *vap)
415 return ieee80211_check_scan(vap,
416 IEEE80211_SCAN_ACTIVE,
417 IEEE80211_SCAN_FOREVER, 0, 0,
418 vap->iv_des_nssid, vap->iv_des_ssid);
422 * Restart a previous scan. If the previous scan completed
423 * then we start again using the existing channel list.
426 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
428 struct ieee80211com *ic = vap->iv_ic;
429 const struct ieee80211_scanner *scan;
431 // IEEE80211_UNLOCK_ASSERT(sc);
433 scan = ieee80211_scanner_get(vap->iv_opmode);
435 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
436 "%s: no scanner support for %s mode\n",
437 __func__, vap->iv_opmode);
443 * XXX TODO: pull apart the bgscan logic into whatever
444 * belongs here and whatever belongs in the software
447 return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
451 * Cancel any scan currently going on for the specified vap.
454 ieee80211_cancel_scan(struct ieee80211vap *vap)
456 struct ieee80211com *ic = vap->iv_ic;
458 ic->ic_scan_methods->sc_cancel_scan(vap);
462 * Cancel any scan currently going on.
464 * This is called during normal 802.11 data path to cancel
465 * a scan so a newly arrived normal data packet can be sent.
468 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
470 struct ieee80211com *ic = vap->iv_ic;
472 ic->ic_scan_methods->sc_cancel_anyscan(vap);
476 * Manually switch to the next channel in the channel list.
477 * Provided for drivers that manage scanning themselves
478 * (e.g. for firmware-based devices).
481 ieee80211_scan_next(struct ieee80211vap *vap)
483 struct ieee80211com *ic = vap->iv_ic;
485 ic->ic_scan_methods->sc_scan_next(vap);
489 * Manually stop a scan that is currently running.
490 * Provided for drivers that are not able to scan single channels
491 * (e.g. for firmware-based devices).
494 ieee80211_scan_done(struct ieee80211vap *vap)
496 struct ieee80211com *ic = vap->iv_ic;
497 struct ieee80211_scan_state *ss;
499 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
503 ss->ss_next = ss->ss_last; /* all channels are complete */
505 ic->ic_scan_methods->sc_scan_done(vap);
507 IEEE80211_UNLOCK(ic);
511 * Probe the current channel, if allowed, while scanning.
512 * If the channel is not marked passive-only then send
513 * a probe request immediately. Otherwise mark state and
514 * listen for beacons on the channel; if we receive something
515 * then we'll transmit a probe request.
518 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
520 struct ieee80211com *ic = vap->iv_ic;
522 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
523 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
527 ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
530 #ifdef IEEE80211_DEBUG
532 dump_country(const uint8_t *ie)
534 const struct ieee80211_country_ie *cie =
535 (const struct ieee80211_country_ie *) ie;
536 int i, nbands, schan, nchan;
539 printf(" <bogus country ie, len %d>", cie->len);
542 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
543 nbands = (cie->len - 3) / sizeof(cie->band[0]);
544 for (i = 0; i < nbands; i++) {
545 schan = cie->band[i].schan;
546 nchan = cie->band[i].nchan;
548 printf(" %u-%u,%u", schan, schan + nchan-1,
549 cie->band[i].maxtxpwr);
551 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
557 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
558 const uint8_t mac[IEEE80211_ADDR_LEN],
559 const struct ieee80211_scanparams *sp, int rssi)
562 printf("[%s] %s%s on chan %u (bss chan %u) ",
563 ether_sprintf(mac), isnew ? "new " : "",
564 ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
565 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
566 printf(" rssi %d\n", rssi);
569 printf("[%s] caps 0x%x bintval %u erp 0x%x",
570 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
571 if (sp->country != NULL)
572 dump_country(sp->country);
576 #endif /* IEEE80211_DEBUG */
579 * Process a beacon or probe response frame.
582 ieee80211_add_scan(struct ieee80211vap *vap,
583 struct ieee80211_channel *curchan,
584 const struct ieee80211_scanparams *sp,
585 const struct ieee80211_frame *wh,
586 int subtype, int rssi, int noise)
588 struct ieee80211com *ic = vap->iv_ic;
590 return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
595 * Timeout/age scan cache entries; called from sta timeout
596 * timer (XXX should be self-contained).
599 ieee80211_scan_timeout(struct ieee80211com *ic)
601 struct ieee80211_scan_state *ss = ic->ic_scan;
603 if (ss->ss_ops != NULL)
604 ss->ss_ops->scan_age(ss);
608 * Mark a scan cache entry after a successful associate.
611 ieee80211_scan_assoc_success(struct ieee80211vap *vap,
612 const uint8_t mac[IEEE80211_ADDR_LEN])
614 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
616 if (ss->ss_ops != NULL) {
617 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
618 mac, "%s", __func__);
619 ss->ss_ops->scan_assoc_success(ss, mac);
624 * Demerit a scan cache entry after failing to associate.
627 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
628 const uint8_t mac[IEEE80211_ADDR_LEN], int reason)
630 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
632 if (ss->ss_ops != NULL) {
633 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
634 "%s: reason %u", __func__, reason);
635 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
640 * Iterate over the contents of the scan cache.
643 ieee80211_scan_iterate(struct ieee80211vap *vap,
644 ieee80211_scan_iter_func *f, void *arg)
646 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
648 if (ss->ss_ops != NULL)
649 ss->ss_ops->scan_iterate(ss, f, arg);
653 * Flush the contents of the scan cache.
656 ieee80211_scan_flush(struct ieee80211vap *vap)
658 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
660 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
661 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
662 ss->ss_ops->scan_flush(ss);
667 * Check the scan cache for an ap/channel to use; if that
668 * fails then kick off a new scan.
670 struct ieee80211_channel *
671 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
673 struct ieee80211_scan_state *ss = ic->ic_scan;
675 IEEE80211_LOCK_ASSERT(ic);
677 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
681 if (ss->ss_ops->scan_pickchan == NULL) {
682 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
683 "%s: scan module does not support picking a channel, "
684 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
687 return ss->ss_ops->scan_pickchan(ss, flags);