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;
134 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
135 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
136 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
138 vap->iv_roaming = IEEE80211_ROAMING_AUTO;
139 memcpy(vap->iv_roamparms, defroam, sizeof(defroam));
141 ic->ic_scan_methods->sc_vattach(vap);
145 ieee80211_scan_vdetach(struct ieee80211vap *vap)
147 struct ieee80211com *ic = vap->iv_ic;
148 struct ieee80211_scan_state *ss;
153 ic->ic_scan_methods->sc_vdetach(vap);
155 if (ss != NULL && ss->ss_vap == vap) {
156 if (ss->ss_ops != NULL) {
157 ss->ss_ops->scan_detach(ss);
162 IEEE80211_UNLOCK(ic);
166 * Simple-minded scanner module support.
168 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
169 "wlan_scan_sta", /* IEEE80211_M_IBSS */
170 "wlan_scan_sta", /* IEEE80211_M_STA */
171 "wlan_scan_wds", /* IEEE80211_M_WDS */
172 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */
173 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */
174 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */
175 "wlan_scan_sta", /* IEEE80211_M_MBSS */
177 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
179 const struct ieee80211_scanner *
180 ieee80211_scanner_get(enum ieee80211_opmode mode)
182 if (mode >= IEEE80211_OPMODE_MAX)
184 if (scanners[mode] == NULL)
185 ieee80211_load_module(scan_modnames[mode]);
186 return scanners[mode];
190 ieee80211_scanner_register(enum ieee80211_opmode mode,
191 const struct ieee80211_scanner *scan)
193 if (mode >= IEEE80211_OPMODE_MAX)
195 scanners[mode] = scan;
199 ieee80211_scanner_unregister(enum ieee80211_opmode mode,
200 const struct ieee80211_scanner *scan)
202 if (mode >= IEEE80211_OPMODE_MAX)
204 if (scanners[mode] == scan)
205 scanners[mode] = NULL;
209 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
213 for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
214 if (scanners[m] == scan)
219 * Update common scanner state to reflect the current
220 * operating mode. This is called when the state machine
221 * is transitioned to RUN state w/o scanning--e.g. when
222 * operating in monitor mode. The purpose of this is to
223 * ensure later callbacks find ss_ops set to properly
224 * reflect current operating mode.
227 ieee80211_scan_update_locked(struct ieee80211vap *vap,
228 const struct ieee80211_scanner *scan)
230 struct ieee80211com *ic = vap->iv_ic;
231 struct ieee80211_scan_state *ss = ic->ic_scan;
233 IEEE80211_LOCK_ASSERT(ic);
235 #ifdef IEEE80211_DEBUG
236 if (ss->ss_vap != vap || ss->ss_ops != scan) {
237 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
238 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
241 ss->ss_vap->iv_ifp->if_xname : "none",
243 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
244 vap->iv_ifp->if_xname,
245 ieee80211_opmode_name[vap->iv_opmode]);
249 if (ss->ss_ops != scan) {
251 * Switch scanners; detach old, attach new. Special
252 * case where a single scan module implements multiple
253 * policies by using different scan ops but a common
254 * core. We assume if the old and new attach methods
255 * are identical then it's ok to just change ss_ops
256 * and not flush the internal state of the module.
258 if (scan == NULL || ss->ss_ops == NULL ||
259 ss->ss_ops->scan_attach != scan->scan_attach) {
260 if (ss->ss_ops != NULL)
261 ss->ss_ops->scan_detach(ss);
262 if (scan != NULL && !scan->scan_attach(ss)) {
263 /* XXX attach failure */
273 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
275 struct ieee80211com *ic = ss->ss_ic;
280 for (i = ss->ss_next; i < ss->ss_last; i++) {
281 const struct ieee80211_channel *c = ss->ss_chans[i];
283 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
284 ieee80211_channel_type_char(c));
289 #ifdef IEEE80211_DEBUG
291 ieee80211_scan_dump(struct ieee80211_scan_state *ss)
293 struct ieee80211vap *vap = ss->ss_vap;
295 if_printf(vap->iv_ifp, "scan set ");
296 ieee80211_scan_dump_channels(ss);
297 printf(" dwell min %lums max %lums\n",
298 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
300 #endif /* IEEE80211_DEBUG */
303 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
304 int nssid, const struct ieee80211_scan_ssid ssids[])
306 if (nssid > IEEE80211_SCAN_MAX_SSID) {
308 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
309 "%s: too many ssid %d, ignoring all of them\n",
313 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
314 ss->ss_nssid = nssid;
318 * Start a scan unless one is already going.
321 ieee80211_start_scan(struct ieee80211vap *vap, int flags,
322 u_int duration, u_int mindwell, u_int maxdwell,
323 u_int nssid, const struct ieee80211_scan_ssid ssids[])
325 const struct ieee80211_scanner *scan;
326 struct ieee80211com *ic = vap->iv_ic;
328 scan = ieee80211_scanner_get(vap->iv_opmode);
330 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
331 "%s: no scanner support for %s mode\n",
332 __func__, ieee80211_opmode_name[vap->iv_opmode]);
337 return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
338 mindwell, maxdwell, nssid, ssids);
342 * Check the scan cache for an ap/channel to use; if that
343 * fails then kick off a new scan.
346 ieee80211_check_scan(struct ieee80211vap *vap, int flags,
347 u_int duration, u_int mindwell, u_int maxdwell,
348 u_int nssid, const struct ieee80211_scan_ssid ssids[])
350 struct ieee80211com *ic = vap->iv_ic;
351 struct ieee80211_scan_state *ss = ic->ic_scan;
352 const struct ieee80211_scanner *scan;
355 scan = ieee80211_scanner_get(vap->iv_opmode);
357 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
358 "%s: no scanner support for %s mode\n",
359 __func__, vap->iv_opmode);
365 * Check if there's a list of scan candidates already.
366 * XXX want more than the ap we're currently associated with
370 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
371 "%s: %s scan, %s%s%s%s%s\n"
373 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
374 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
375 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
376 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
377 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
378 , flags & IEEE80211_SCAN_ONCE ? ", once" : ""
381 if (ss->ss_ops != scan) {
382 /* XXX re-use cache contents? e.g. adhoc<->sta */
383 flags |= IEEE80211_SCAN_FLUSH;
387 * XXX TODO: separate things out a bit better.
389 ieee80211_scan_update_locked(vap, scan);
391 result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
392 mindwell, maxdwell, nssid, ssids);
394 IEEE80211_UNLOCK(ic);
400 * Check the scan cache for an ap/channel to use; if that fails
401 * then kick off a scan using the current settings.
404 ieee80211_check_scan_current(struct ieee80211vap *vap)
406 return ieee80211_check_scan(vap,
407 IEEE80211_SCAN_ACTIVE,
408 IEEE80211_SCAN_FOREVER, 0, 0,
409 vap->iv_des_nssid, vap->iv_des_ssid);
413 * Restart a previous scan. If the previous scan completed
414 * then we start again using the existing channel list.
417 ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
419 struct ieee80211com *ic = vap->iv_ic;
420 const struct ieee80211_scanner *scan;
422 // IEEE80211_UNLOCK_ASSERT(sc);
424 scan = ieee80211_scanner_get(vap->iv_opmode);
426 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
427 "%s: no scanner support for %s mode\n",
428 __func__, vap->iv_opmode);
434 * XXX TODO: pull apart the bgscan logic into whatever
435 * belongs here and whatever belongs in the software
438 return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
442 * Cancel any scan currently going on for the specified vap.
445 ieee80211_cancel_scan(struct ieee80211vap *vap)
447 struct ieee80211com *ic = vap->iv_ic;
449 ic->ic_scan_methods->sc_cancel_scan(vap);
453 * Cancel any scan currently going on.
455 * This is called during normal 802.11 data path to cancel
456 * a scan so a newly arrived normal data packet can be sent.
459 ieee80211_cancel_anyscan(struct ieee80211vap *vap)
461 struct ieee80211com *ic = vap->iv_ic;
463 ic->ic_scan_methods->sc_cancel_anyscan(vap);
467 * Manually switch to the next channel in the channel list.
468 * Provided for drivers that manage scanning themselves
469 * (e.g. for firmware-based devices).
472 ieee80211_scan_next(struct ieee80211vap *vap)
474 struct ieee80211com *ic = vap->iv_ic;
476 ic->ic_scan_methods->sc_scan_next(vap);
480 * Manually stop a scan that is currently running.
481 * Provided for drivers that are not able to scan single channels
482 * (e.g. for firmware-based devices).
485 ieee80211_scan_done(struct ieee80211vap *vap)
487 struct ieee80211com *ic = vap->iv_ic;
488 struct ieee80211_scan_state *ss;
490 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
494 ss->ss_next = ss->ss_last; /* all channels are complete */
496 ic->ic_scan_methods->sc_scan_done(vap);
498 IEEE80211_UNLOCK(ic);
502 * Probe the current channel, if allowed, while scanning.
503 * If the channel is not marked passive-only then send
504 * a probe request immediately. Otherwise mark state and
505 * listen for beacons on the channel; if we receive something
506 * then we'll transmit a probe request.
509 ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
511 struct ieee80211com *ic = vap->iv_ic;
513 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
514 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
518 ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
521 #ifdef IEEE80211_DEBUG
523 dump_country(const uint8_t *ie)
525 const struct ieee80211_country_ie *cie =
526 (const struct ieee80211_country_ie *) ie;
527 int i, nbands, schan, nchan;
530 printf(" <bogus country ie, len %d>", cie->len);
533 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
534 nbands = (cie->len - 3) / sizeof(cie->band[0]);
535 for (i = 0; i < nbands; i++) {
536 schan = cie->band[i].schan;
537 nchan = cie->band[i].nchan;
539 printf(" %u-%u,%u", schan, schan + nchan-1,
540 cie->band[i].maxtxpwr);
542 printf(" %u,%u", schan, cie->band[i].maxtxpwr);
548 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
549 const uint8_t mac[IEEE80211_ADDR_LEN],
550 const struct ieee80211_scanparams *sp, int rssi)
553 printf("[%s] %s%s on chan %u (bss chan %u) ",
554 ether_sprintf(mac), isnew ? "new " : "",
555 ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
556 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
557 printf(" rssi %d\n", rssi);
560 printf("[%s] caps 0x%x bintval %u erp 0x%x",
561 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
562 if (sp->country != NULL)
563 dump_country(sp->country);
567 #endif /* IEEE80211_DEBUG */
570 * Process a beacon or probe response frame.
573 ieee80211_add_scan(struct ieee80211vap *vap,
574 struct ieee80211_channel *curchan,
575 const struct ieee80211_scanparams *sp,
576 const struct ieee80211_frame *wh,
577 int subtype, int rssi, int noise)
579 struct ieee80211com *ic = vap->iv_ic;
581 return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
586 * Timeout/age scan cache entries; called from sta timeout
587 * timer (XXX should be self-contained).
590 ieee80211_scan_timeout(struct ieee80211com *ic)
592 struct ieee80211_scan_state *ss = ic->ic_scan;
594 if (ss->ss_ops != NULL)
595 ss->ss_ops->scan_age(ss);
599 * Mark a scan cache entry after a successful associate.
602 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[])
604 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
606 if (ss->ss_ops != NULL) {
607 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
608 mac, "%s", __func__);
609 ss->ss_ops->scan_assoc_success(ss, mac);
614 * Demerit a scan cache entry after failing to associate.
617 ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
618 const uint8_t mac[], int reason)
620 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
622 if (ss->ss_ops != NULL) {
623 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
624 "%s: reason %u", __func__, reason);
625 ss->ss_ops->scan_assoc_fail(ss, mac, reason);
630 * Iterate over the contents of the scan cache.
633 ieee80211_scan_iterate(struct ieee80211vap *vap,
634 ieee80211_scan_iter_func *f, void *arg)
636 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
638 if (ss->ss_ops != NULL)
639 ss->ss_ops->scan_iterate(ss, f, arg);
643 * Flush the contents of the scan cache.
646 ieee80211_scan_flush(struct ieee80211vap *vap)
648 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
650 if (ss->ss_ops != NULL && ss->ss_vap == vap) {
651 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
652 ss->ss_ops->scan_flush(ss);
657 * Check the scan cache for an ap/channel to use; if that
658 * fails then kick off a new scan.
660 struct ieee80211_channel *
661 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
663 struct ieee80211_scan_state *ss = ic->ic_scan;
665 IEEE80211_LOCK_ASSERT(ic);
667 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
671 if (ss->ss_ops->scan_pickchan == NULL) {
672 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
673 "%s: scan module does not support picking a channel, "
674 "opmode %s\n", __func__, ss->ss_vap->iv_opmode);
677 return ss->ss_ops->scan_pickchan(ss, flags);