xref: /freebsd/sys/net80211/ieee80211_node.c (revision f856af0466c076beef4ea9b15d088e1119a945b8)
1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * Alternatively, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2 as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/mbuf.h>
39 #include <sys/malloc.h>
40 #include <sys/kernel.h>
41 
42 #include <sys/socket.h>
43 
44 #include <net/if.h>
45 #include <net/if_media.h>
46 #include <net/ethernet.h>
47 
48 #include <net80211/ieee80211_var.h>
49 
50 #include <net/bpf.h>
51 
52 /*
53  * Association id's are managed with a bit vector.
54  */
55 #define	IEEE80211_AID_SET(b, w) \
56 	((w)[IEEE80211_AID(b) / 32] |= (1 << (IEEE80211_AID(b) % 32)))
57 #define	IEEE80211_AID_CLR(b, w) \
58 	((w)[IEEE80211_AID(b) / 32] &= ~(1 << (IEEE80211_AID(b) % 32)))
59 #define	IEEE80211_AID_ISSET(b, w) \
60 	((w)[IEEE80211_AID(b) / 32] & (1 << (IEEE80211_AID(b) % 32)))
61 
62 #ifdef IEEE80211_DEBUG_REFCNT
63 #define REFCNT_LOC "%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line
64 #else
65 #define REFCNT_LOC "%s %p<%s> refcnt %d\n", __func__
66 #endif
67 
68 static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
69 static void node_cleanup(struct ieee80211_node *);
70 static void node_free(struct ieee80211_node *);
71 static u_int8_t node_getrssi(const struct ieee80211_node *);
72 
73 static void ieee80211_setup_node(struct ieee80211_node_table *,
74 		struct ieee80211_node *, const u_int8_t *);
75 static void _ieee80211_free_node(struct ieee80211_node *);
76 static void ieee80211_free_allnodes(struct ieee80211_node_table *);
77 
78 static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
79 static void ieee80211_timeout_stations(struct ieee80211_node_table *);
80 
81 static void ieee80211_set_tim(struct ieee80211_node *, int set);
82 
83 static void ieee80211_node_table_init(struct ieee80211com *ic,
84 	struct ieee80211_node_table *nt, const char *name,
85 	int inact, int keyixmax,
86 	void (*timeout)(struct ieee80211_node_table *));
87 static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
88 
89 MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
90 
91 void
92 ieee80211_node_attach(struct ieee80211com *ic)
93 {
94 
95 	ic->ic_node_alloc = node_alloc;
96 	ic->ic_node_free = node_free;
97 	ic->ic_node_cleanup = node_cleanup;
98 	ic->ic_node_getrssi = node_getrssi;
99 
100 	/* default station inactivity timer setings */
101 	ic->ic_inact_init = IEEE80211_INACT_INIT;
102 	ic->ic_inact_auth = IEEE80211_INACT_AUTH;
103 	ic->ic_inact_run = IEEE80211_INACT_RUN;
104 	ic->ic_inact_probe = IEEE80211_INACT_PROBE;
105 
106 	/* NB: driver should override */
107 	ic->ic_max_aid = IEEE80211_AID_DEF;
108 	ic->ic_set_tim = ieee80211_set_tim;
109 }
110 
111 void
112 ieee80211_node_lateattach(struct ieee80211com *ic)
113 {
114 	struct ieee80211_rsnparms *rsn;
115 
116 	if (ic->ic_max_aid > IEEE80211_AID_MAX)
117 		ic->ic_max_aid = IEEE80211_AID_MAX;
118 	MALLOC(ic->ic_aid_bitmap, u_int32_t *,
119 		howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
120 		M_DEVBUF, M_NOWAIT | M_ZERO);
121 	if (ic->ic_aid_bitmap == NULL) {
122 		/* XXX no way to recover */
123 		printf("%s: no memory for AID bitmap!\n", __func__);
124 		ic->ic_max_aid = 0;
125 	}
126 
127 	/* XXX defer until using hostap/ibss mode */
128 	ic->ic_tim_len = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
129 	MALLOC(ic->ic_tim_bitmap, u_int8_t *, ic->ic_tim_len,
130 		M_DEVBUF, M_NOWAIT | M_ZERO);
131 	if (ic->ic_tim_bitmap == NULL) {
132 		/* XXX no way to recover */
133 		printf("%s: no memory for TIM bitmap!\n", __func__);
134 	}
135 
136 	ieee80211_node_table_init(ic, &ic->ic_sta, "station",
137 		IEEE80211_INACT_INIT, ic->ic_crypto.cs_max_keyix,
138 		ieee80211_timeout_stations);
139 	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
140 		IEEE80211_INACT_SCAN, 0,
141 		ieee80211_timeout_scan_candidates);
142 
143 	ieee80211_reset_bss(ic);
144 	/*
145 	 * Setup "global settings" in the bss node so that
146 	 * each new station automatically inherits them.
147 	 */
148 	rsn = &ic->ic_bss->ni_rsn;
149 	/* WEP, TKIP, and AES-CCM are always supported */
150 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
151 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
152 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
153 	if (ic->ic_caps & IEEE80211_C_AES)
154 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
155 	if (ic->ic_caps & IEEE80211_C_CKIP)
156 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
157 	/*
158 	 * Default unicast cipher to WEP for 802.1x use.  If
159 	 * WPA is enabled the management code will set these
160 	 * values to reflect.
161 	 */
162 	rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
163 	rsn->rsn_ucastkeylen = 104 / NBBY;
164 	/*
165 	 * WPA says the multicast cipher is the lowest unicast
166 	 * cipher supported.  But we skip WEP which would
167 	 * otherwise be used based on this criteria.
168 	 */
169 	rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
170 	rsn->rsn_mcastkeylen = 128 / NBBY;
171 
172 	/*
173 	 * We support both WPA-PSK and 802.1x; the one used
174 	 * is determined by the authentication mode and the
175 	 * setting of the PSK state.
176 	 */
177 	rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
178 	rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
179 
180 	ic->ic_auth = ieee80211_authenticator_get(ic->ic_bss->ni_authmode);
181 }
182 
183 void
184 ieee80211_node_detach(struct ieee80211com *ic)
185 {
186 
187 	if (ic->ic_bss != NULL) {
188 		ieee80211_free_node(ic->ic_bss);
189 		ic->ic_bss = NULL;
190 	}
191 	ieee80211_node_table_cleanup(&ic->ic_scan);
192 	ieee80211_node_table_cleanup(&ic->ic_sta);
193 	if (ic->ic_aid_bitmap != NULL) {
194 		FREE(ic->ic_aid_bitmap, M_DEVBUF);
195 		ic->ic_aid_bitmap = NULL;
196 	}
197 	if (ic->ic_tim_bitmap != NULL) {
198 		FREE(ic->ic_tim_bitmap, M_DEVBUF);
199 		ic->ic_tim_bitmap = NULL;
200 	}
201 }
202 
203 /*
204  * Port authorize/unauthorize interfaces for use by an authenticator.
205  */
206 
207 void
208 ieee80211_node_authorize(struct ieee80211_node *ni)
209 {
210 	struct ieee80211com *ic = ni->ni_ic;
211 
212 	ni->ni_flags |= IEEE80211_NODE_AUTH;
213 	ni->ni_inact_reload = ic->ic_inact_run;
214 }
215 
216 void
217 ieee80211_node_unauthorize(struct ieee80211_node *ni)
218 {
219 	ni->ni_flags &= ~IEEE80211_NODE_AUTH;
220 }
221 
222 /*
223  * Set/change the channel.  The rate set is also updated as
224  * to insure a consistent view by drivers.
225  */
226 static void
227 ieee80211_set_chan(struct ieee80211com *ic,
228 	struct ieee80211_node *ni, struct ieee80211_channel *chan)
229 {
230 	if (chan == IEEE80211_CHAN_ANYC)	/* XXX while scanning */
231 		chan = ic->ic_curchan;
232 	ni->ni_chan = chan;
233 	ni->ni_rates = *ieee80211_get_suprates(ic, chan);
234 }
235 
236 /*
237  * AP scanning support.
238  */
239 
240 #ifdef IEEE80211_DEBUG
241 static void
242 dump_chanlist(const u_char chans[])
243 {
244 	const char *sep;
245 	int i;
246 
247 	sep = " ";
248 	for (i = 0; i < IEEE80211_CHAN_MAX; i++)
249 		if (isset(chans, i)) {
250 			printf("%s%u", sep, i);
251 			sep = ", ";
252 		}
253 }
254 #endif /* IEEE80211_DEBUG */
255 
256 /*
257  * Initialize the channel set to scan based on the
258  * of available channels and the current PHY mode.
259  */
260 static void
261 ieee80211_reset_scan(struct ieee80211com *ic)
262 {
263 
264 	/* XXX ic_des_chan should be handled with ic_chan_active */
265 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
266 		memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
267 		setbit(ic->ic_chan_scan,
268 			ieee80211_chan2ieee(ic, ic->ic_des_chan));
269 	} else
270 		memcpy(ic->ic_chan_scan, ic->ic_chan_active,
271 			sizeof(ic->ic_chan_active));
272 #ifdef IEEE80211_DEBUG
273 	if (ieee80211_msg_scan(ic)) {
274 		printf("%s: scan set:", __func__);
275 		dump_chanlist(ic->ic_chan_scan);
276 		printf(" start chan %u\n",
277 			ieee80211_chan2ieee(ic, ic->ic_curchan));
278 	}
279 #endif /* IEEE80211_DEBUG */
280 }
281 
282 /*
283  * Begin an active scan.
284  */
285 void
286 ieee80211_begin_scan(struct ieee80211com *ic, int reset)
287 {
288 
289 	ic->ic_scan.nt_scangen++;
290 	/*
291 	 * In all but hostap mode scanning starts off in
292 	 * an active mode before switching to passive.
293 	 */
294 	if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
295 		ic->ic_flags |= IEEE80211_F_ASCAN;
296 		ic->ic_stats.is_scan_active++;
297 	} else
298 		ic->ic_stats.is_scan_passive++;
299 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
300 		"begin %s scan in %s mode, scangen %u\n",
301 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
302 		ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
303 	/*
304 	 * Clear scan state and flush any previously seen AP's.
305 	 */
306 	ieee80211_reset_scan(ic);
307 	if (reset)
308 		ieee80211_free_allnodes(&ic->ic_scan);
309 
310 	ic->ic_flags |= IEEE80211_F_SCAN;
311 
312 	/* Scan the next channel. */
313 	ieee80211_next_scan(ic);
314 }
315 
316 /*
317  * Switch to the next channel marked for scanning.
318  */
319 int
320 ieee80211_next_scan(struct ieee80211com *ic)
321 {
322 	struct ieee80211_channel *chan;
323 
324 	/*
325 	 * Insure any previous mgt frame timeouts don't fire.
326 	 * This assumes the driver does the right thing in
327 	 * flushing anything queued in the driver and below.
328 	 */
329 	ic->ic_mgt_timer = 0;
330 	ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
331 
332 	chan = ic->ic_curchan;
333 	do {
334 		if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
335 			chan = &ic->ic_channels[0];
336 		if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
337 			clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
338 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
339 			    "%s: chan %d->%d\n", __func__,
340 			    ieee80211_chan2ieee(ic, ic->ic_curchan),
341 			    ieee80211_chan2ieee(ic, chan));
342 			ic->ic_curchan = chan;
343 			/*
344 			 * XXX drivers should do this as needed,
345 			 * XXX for now maintain compatibility
346 			 */
347 			ic->ic_bss->ni_rates = *ieee80211_get_suprates(ic, chan);
348 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
349 			return 1;
350 		}
351 	} while (chan != ic->ic_curchan);
352 	ieee80211_end_scan(ic);
353 	return 0;
354 }
355 
356 /*
357  * Probe the curent channel, if allowed, while scanning.
358  * If the channel is not marked passive-only then send
359  * a probe request immediately.  Otherwise mark state and
360  * listen for beacons on the channel; if we receive something
361  * then we'll transmit a probe request.
362  */
363 void
364 ieee80211_probe_curchan(struct ieee80211com *ic, int force)
365 {
366 	struct ifnet *ifp = ic->ic_ifp;
367 
368 	if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 || force) {
369 		/*
370 		 * XXX send both broadcast+directed probe request
371 		 */
372 		ieee80211_send_probereq(ic->ic_bss,
373 			ic->ic_myaddr, ifp->if_broadcastaddr,
374 			ifp->if_broadcastaddr,
375 			ic->ic_des_essid, ic->ic_des_esslen,
376 			ic->ic_opt_ie, ic->ic_opt_ie_len);
377 	} else
378 		ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
379 }
380 
381 static __inline void
382 copy_bss(struct ieee80211_node *nbss, const struct ieee80211_node *obss)
383 {
384 	/* propagate useful state */
385 	nbss->ni_authmode = obss->ni_authmode;
386 	nbss->ni_txpower = obss->ni_txpower;
387 	nbss->ni_vlan = obss->ni_vlan;
388 	nbss->ni_rsn = obss->ni_rsn;
389 	/* XXX statistics? */
390 }
391 
392 void
393 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
394 {
395 	struct ieee80211_node_table *nt;
396 	struct ieee80211_node *ni;
397 
398 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
399 		"%s: creating ibss\n", __func__);
400 
401 	/*
402 	 * Create the station/neighbor table.  Note that for adhoc
403 	 * mode we make the initial inactivity timer longer since
404 	 * we create nodes only through discovery and they typically
405 	 * are long-lived associations.
406 	 */
407 	nt = &ic->ic_sta;
408 	IEEE80211_NODE_LOCK(nt);
409 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
410 		nt->nt_name = "station";
411 		nt->nt_inact_init = ic->ic_inact_init;
412 	} else {
413 		nt->nt_name = "neighbor";
414 		nt->nt_inact_init = ic->ic_inact_run;
415 	}
416 	IEEE80211_NODE_UNLOCK(nt);
417 
418 	ni = ieee80211_alloc_node(&ic->ic_sta, ic->ic_myaddr);
419 	if (ni == NULL) {
420 		/* XXX recovery? */
421 		return;
422 	}
423 	IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
424 	ni->ni_esslen = ic->ic_des_esslen;
425 	memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
426 	copy_bss(ni, ic->ic_bss);
427 	ni->ni_intval = ic->ic_bintval;
428 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
429 		ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
430 	if (ic->ic_phytype == IEEE80211_T_FH) {
431 		ni->ni_fhdwell = 200;	/* XXX */
432 		ni->ni_fhindex = 1;
433 	}
434 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
435 		ic->ic_flags |= IEEE80211_F_SIBSS;
436 		ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;	/* XXX */
437 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
438 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
439 		else
440 			ni->ni_bssid[0] |= 0x02;	/* local bit for IBSS */
441 	} else if (ic->ic_opmode == IEEE80211_M_AHDEMO) {
442 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
443 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
444 		else
445 			memset(ni->ni_bssid, 0, IEEE80211_ADDR_LEN);
446 	}
447 	/*
448 	 * Fix the channel and related attributes.
449 	 */
450 	ieee80211_set_chan(ic, ni, chan);
451 	ic->ic_curchan = chan;
452 	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
453 	/*
454 	 * Do mode-specific rate setup.
455 	 */
456 	if (ic->ic_curmode == IEEE80211_MODE_11G) {
457 		/*
458 		 * Use a mixed 11b/11g rate set.
459 		 */
460 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
461 	} else if (ic->ic_curmode == IEEE80211_MODE_11B) {
462 		/*
463 		 * Force pure 11b rate set.
464 		 */
465 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
466 	}
467 
468 	(void) ieee80211_sta_join(ic, ieee80211_ref_node(ni));
469 }
470 
471 void
472 ieee80211_reset_bss(struct ieee80211com *ic)
473 {
474 	struct ieee80211_node *ni, *obss;
475 
476 	ieee80211_node_table_reset(&ic->ic_scan);
477 	ieee80211_node_table_reset(&ic->ic_sta);
478 
479 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
480 	KASSERT(ni != NULL, ("unable to setup inital BSS node"));
481 	obss = ic->ic_bss;
482 	ic->ic_bss = ieee80211_ref_node(ni);
483 	if (obss != NULL) {
484 		copy_bss(ni, obss);
485 		ni->ni_intval = ic->ic_bintval;
486 		ieee80211_free_node(obss);
487 	}
488 }
489 
490 /* XXX tunable */
491 #define	STA_FAILS_MAX	2		/* assoc failures before ignored */
492 
493 static int
494 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
495 {
496         u_int8_t rate;
497         int fail;
498 
499 	fail = 0;
500 	if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
501 		fail |= 0x01;
502 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
503 	    ni->ni_chan != ic->ic_des_chan)
504 		fail |= 0x01;
505 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
506 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
507 			fail |= 0x02;
508 	} else {
509 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
510 			fail |= 0x02;
511 	}
512 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
513 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
514 			fail |= 0x04;
515 	} else {
516 		/* XXX does this mean privacy is supported or required? */
517 		if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
518 			fail |= 0x04;
519 	}
520 	rate = ieee80211_fix_rate(ni, IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
521 	if (rate & IEEE80211_RATE_BASIC)
522 		fail |= 0x08;
523 	if (ic->ic_des_esslen != 0 &&
524 	    (ni->ni_esslen != ic->ic_des_esslen ||
525 	     memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
526 		fail |= 0x10;
527 	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
528 	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
529 		fail |= 0x20;
530 	if (ni->ni_fails >= STA_FAILS_MAX)
531 		fail |= 0x40;
532 #ifdef IEEE80211_DEBUG
533 	if (ieee80211_msg_scan(ic)) {
534 		printf(" %c %s",
535 		    fail & 0x40 ? '=' : fail & 0x80 ? '^' : fail ? '-' : '+',
536 		    ether_sprintf(ni->ni_macaddr));
537 		printf(" %s%c", ether_sprintf(ni->ni_bssid),
538 		    fail & 0x20 ? '!' : ' ');
539 		printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
540 			fail & 0x01 ? '!' : ' ');
541 		printf(" %+4d", ni->ni_rssi);
542 		printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
543 		    fail & 0x08 ? '!' : ' ');
544 		printf(" %4s%c",
545 		    (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
546 		    (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
547 		    "????",
548 		    fail & 0x02 ? '!' : ' ');
549 		printf(" %3s%c ",
550 		    (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
551 		    "wep" : "no",
552 		    fail & 0x04 ? '!' : ' ');
553 		ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
554 		printf("%s\n", fail & 0x10 ? "!" : "");
555 	}
556 #endif
557 	return fail;
558 }
559 
560 static __inline u_int8_t
561 maxrate(const struct ieee80211_node *ni)
562 {
563 	const struct ieee80211_rateset *rs = &ni->ni_rates;
564 	/* NB: assumes rate set is sorted (happens on frame receive) */
565 	return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
566 }
567 
568 /*
569  * Compare the capabilities of two nodes and decide which is
570  * more desirable (return >0 if a is considered better).  Note
571  * that we assume compatibility/usability has already been checked
572  * so we don't need to (e.g. validate whether privacy is supported).
573  * Used to select the best scan candidate for association in a BSS.
574  */
575 static int
576 ieee80211_node_compare(struct ieee80211com *ic,
577 		       const struct ieee80211_node *a,
578 		       const struct ieee80211_node *b)
579 {
580 	u_int8_t maxa, maxb;
581 	u_int8_t rssia, rssib;
582 	int weight;
583 
584 	/* privacy support preferred */
585 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
586 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
587 		return 1;
588 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
589 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
590 		return -1;
591 
592 	/* compare count of previous failures */
593 	weight = b->ni_fails - a->ni_fails;
594 	if (abs(weight) > 1)
595 		return weight;
596 
597 	rssia = ic->ic_node_getrssi(a);
598 	rssib = ic->ic_node_getrssi(b);
599 	if (abs(rssib - rssia) < 5) {
600 		/* best/max rate preferred if signal level close enough XXX */
601 		maxa = maxrate(a);
602 		maxb = maxrate(b);
603 		if (maxa != maxb)
604 			return maxa - maxb;
605 		/* XXX use freq for channel preference */
606 		/* for now just prefer 5Ghz band to all other bands */
607 		if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
608 		   !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
609 			return 1;
610 		if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
611 		     IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
612 			return -1;
613 	}
614 	/* all things being equal, use signal level */
615 	return rssia - rssib;
616 }
617 
618 /*
619  * Mark an ongoing scan stopped.
620  */
621 void
622 ieee80211_cancel_scan(struct ieee80211com *ic)
623 {
624 
625 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
626 		__func__,
627 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
628 
629 	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
630 	ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
631 }
632 
633 /*
634  * Complete a scan of potential channels.
635  */
636 void
637 ieee80211_end_scan(struct ieee80211com *ic)
638 {
639 	struct ieee80211_node_table *nt = &ic->ic_scan;
640 	struct ieee80211_node *ni, *selbs;
641 
642 	ieee80211_cancel_scan(ic);
643 	ieee80211_notify_scan_done(ic);
644 
645 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
646 		u_int8_t maxrssi[IEEE80211_CHAN_MAX];	/* XXX off stack? */
647 		int i, bestchan;
648 		u_int8_t rssi;
649 
650 		/*
651 		 * The passive scan to look for existing AP's completed,
652 		 * select a channel to camp on.  Identify the channels
653 		 * that already have one or more AP's and try to locate
654 		 * an unoccupied one.  If that fails, pick a channel that
655 		 * looks to be quietest.
656 		 */
657 		memset(maxrssi, 0, sizeof(maxrssi));
658 		IEEE80211_NODE_LOCK(nt);
659 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
660 			rssi = ic->ic_node_getrssi(ni);
661 			i = ieee80211_chan2ieee(ic, ni->ni_chan);
662 			if (rssi > maxrssi[i])
663 				maxrssi[i] = rssi;
664 		}
665 		IEEE80211_NODE_UNLOCK(nt);
666 		/* XXX select channel more intelligently */
667 		bestchan = -1;
668 		for (i = 0; i < IEEE80211_CHAN_MAX; i++)
669 			if (isset(ic->ic_chan_active, i)) {
670 				/*
671 				 * If the channel is unoccupied the max rssi
672 				 * should be zero; just take it.  Otherwise
673 				 * track the channel with the lowest rssi and
674 				 * use that when all channels appear occupied.
675 				 */
676 				if (maxrssi[i] == 0) {
677 					bestchan = i;
678 					break;
679 				}
680 				if (bestchan == -1 ||
681 				    maxrssi[i] < maxrssi[bestchan])
682 					bestchan = i;
683 			}
684 		if (bestchan != -1) {
685 			ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
686 			return;
687 		}
688 		/* no suitable channel, should not happen */
689 	}
690 
691 	/*
692 	 * When manually sequencing the state machine; scan just once
693 	 * regardless of whether we have a candidate or not.  The
694 	 * controlling application is expected to setup state and
695 	 * initiate an association.
696 	 */
697 	if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
698 		return;
699 	/*
700 	 * Automatic sequencing; look for a candidate and
701 	 * if found join the network.
702 	 */
703 	/* NB: unlocked read should be ok */
704 	if (TAILQ_FIRST(&nt->nt_node) == NULL) {
705 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
706 			"%s: no scan candidate\n", __func__);
707   notfound:
708 		if (ic->ic_opmode == IEEE80211_M_IBSS &&
709 		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
710 		    ic->ic_des_esslen != 0) {
711 			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
712 			return;
713 		}
714 		/*
715 		 * Decrement the failure counts so entries will be
716 		 * reconsidered the next time around.  We really want
717 		 * to do this only for sta's where we've previously
718 		 * had some success.
719 		 */
720 		IEEE80211_NODE_LOCK(nt);
721 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
722 			if (ni->ni_fails)
723 				ni->ni_fails--;
724 		IEEE80211_NODE_UNLOCK(nt);
725 		/*
726 		 * Reset the list of channels to scan and start again.
727 		 */
728 		ieee80211_reset_scan(ic);
729 		ic->ic_flags |= IEEE80211_F_SCAN;
730 		ieee80211_next_scan(ic);
731 		return;
732 	}
733 	selbs = NULL;
734 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
735 	    "macaddr          bssid         chan  rssi rate flag  wep  essid");
736 	IEEE80211_NODE_LOCK(nt);
737 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
738 		if (ieee80211_match_bss(ic, ni) == 0) {
739 			if (selbs == NULL)
740 				selbs = ni;
741 			else if (ieee80211_node_compare(ic, ni, selbs) > 0)
742 				selbs = ni;
743 		}
744 	}
745 	if (selbs != NULL)		/* NB: grab ref while dropping lock */
746 		(void) ieee80211_ref_node(selbs);
747 	IEEE80211_NODE_UNLOCK(nt);
748 	if (selbs == NULL)
749 		goto notfound;
750 	if (!ieee80211_sta_join(ic, selbs)) {
751 		ieee80211_free_node(selbs);
752 		goto notfound;
753 	}
754 }
755 
756 /*
757  * Handle 802.11 ad hoc network merge.  The
758  * convention, set by the Wireless Ethernet Compatibility Alliance
759  * (WECA), is that an 802.11 station will change its BSSID to match
760  * the "oldest" 802.11 ad hoc network, on the same channel, that
761  * has the station's desired SSID.  The "oldest" 802.11 network
762  * sends beacons with the greatest TSF timestamp.
763  *
764  * The caller is assumed to validate TSF's before attempting a merge.
765  *
766  * Return !0 if the BSSID changed, 0 otherwise.
767  */
768 int
769 ieee80211_ibss_merge(struct ieee80211_node *ni)
770 {
771 	struct ieee80211com *ic = ni->ni_ic;
772 
773 	if (ni == ic->ic_bss ||
774 	    IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
775 		/* unchanged, nothing to do */
776 		return 0;
777 	}
778 	if (ieee80211_match_bss(ic, ni) != 0) {	/* capabilities mismatch */
779 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
780 		    "%s: merge failed, capabilities mismatch\n", __func__);
781 		ic->ic_stats.is_ibss_capmismatch++;
782 		return 0;
783 	}
784 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
785 		"%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
786 		ether_sprintf(ni->ni_bssid),
787 		ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
788 		ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
789 		ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
790 	);
791 	return ieee80211_sta_join(ic, ieee80211_ref_node(ni));
792 }
793 
794 /*
795  * Join the specified IBSS/BSS network.  The node is assumed to
796  * be passed in with a held reference.
797  */
798 int
799 ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
800 {
801 	struct ieee80211_node *obss;
802 
803 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
804 		struct ieee80211_node_table *nt;
805 		/*
806 		 * Delete unusable rates; we've already checked
807 		 * that the negotiated rate set is acceptable.
808 		 */
809 		ieee80211_fix_rate(selbs, IEEE80211_F_DODEL);
810 		/*
811 		 * Fillin the neighbor table; it will already
812 		 * exist if we are simply switching mastership.
813 		 * XXX ic_sta always setup so this is unnecessary?
814 		 */
815 		nt = &ic->ic_sta;
816 		IEEE80211_NODE_LOCK(nt);
817 		nt->nt_name = "neighbor";
818 		nt->nt_inact_init = ic->ic_inact_run;
819 		IEEE80211_NODE_UNLOCK(nt);
820 	}
821 
822 	/*
823 	 * Committed to selbs, setup state.
824 	 */
825 	obss = ic->ic_bss;
826 	ic->ic_bss = selbs;		/* NB: caller assumed to bump refcnt */
827 	if (obss != NULL) {
828 		copy_bss(selbs, obss);
829 		ieee80211_free_node(obss);
830 	}
831 	/*
832 	 * Set the erp state (mostly the slot time) to deal with
833 	 * the auto-select case; this should be redundant if the
834 	 * mode is locked.
835 	 */
836 	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
837 	ic->ic_curchan = selbs->ni_chan;
838 	ieee80211_reset_erp(ic);
839 	ieee80211_wme_initparams(ic);
840 
841 	if (ic->ic_opmode == IEEE80211_M_STA)
842 		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
843 	else
844 		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
845 	return 1;
846 }
847 
848 /*
849  * Leave the specified IBSS/BSS network.  The node is assumed to
850  * be passed in with a held reference.
851  */
852 void
853 ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
854 {
855 	ic->ic_node_cleanup(ni);
856 	ieee80211_notify_node_leave(ic, ni);
857 }
858 
859 static struct ieee80211_node *
860 node_alloc(struct ieee80211_node_table *nt)
861 {
862 	struct ieee80211_node *ni;
863 
864 	MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
865 		M_80211_NODE, M_NOWAIT | M_ZERO);
866 	return ni;
867 }
868 
869 /*
870  * Reclaim any resources in a node and reset any critical
871  * state.  Typically nodes are free'd immediately after,
872  * but in some cases the storage may be reused so we need
873  * to insure consistent state (should probably fix that).
874  */
875 static void
876 node_cleanup(struct ieee80211_node *ni)
877 {
878 #define	N(a)	(sizeof(a)/sizeof(a[0]))
879 	struct ieee80211com *ic = ni->ni_ic;
880 	int i, qlen;
881 
882 	/* NB: preserve ni_table */
883 	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
884 		ic->ic_ps_sta--;
885 		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
886 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
887 		    "[%s] power save mode off, %u sta's in ps mode\n",
888 		    ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
889 	}
890 	/*
891 	 * Clear AREF flag that marks the authorization refcnt bump
892 	 * has happened.  This is probably not needed as the node
893 	 * should always be removed from the table so not found but
894 	 * do it just in case.
895 	 */
896 	ni->ni_flags &= ~IEEE80211_NODE_AREF;
897 
898 	/*
899 	 * Drain power save queue and, if needed, clear TIM.
900 	 */
901 	IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
902 	if (qlen != 0 && ic->ic_set_tim != NULL)
903 		ic->ic_set_tim(ni, 0);
904 
905 	ni->ni_associd = 0;
906 	if (ni->ni_challenge != NULL) {
907 		FREE(ni->ni_challenge, M_DEVBUF);
908 		ni->ni_challenge = NULL;
909 	}
910 	/*
911 	 * Preserve SSID, WPA, and WME ie's so the bss node is
912 	 * reusable during a re-auth/re-assoc state transition.
913 	 * If we remove these data they will not be recreated
914 	 * because they come from a probe-response or beacon frame
915 	 * which cannot be expected prior to the association-response.
916 	 * This should not be an issue when operating in other modes
917 	 * as stations leaving always go through a full state transition
918 	 * which will rebuild this state.
919 	 *
920 	 * XXX does this leave us open to inheriting old state?
921 	 */
922 	for (i = 0; i < N(ni->ni_rxfrag); i++)
923 		if (ni->ni_rxfrag[i] != NULL) {
924 			m_freem(ni->ni_rxfrag[i]);
925 			ni->ni_rxfrag[i] = NULL;
926 		}
927 	/*
928 	 * Must be careful here to remove any key map entry w/o a LOR.
929 	 */
930 	ieee80211_node_delucastkey(ni);
931 #undef N
932 }
933 
934 static void
935 node_free(struct ieee80211_node *ni)
936 {
937 	struct ieee80211com *ic = ni->ni_ic;
938 
939 	ic->ic_node_cleanup(ni);
940 	if (ni->ni_wpa_ie != NULL)
941 		FREE(ni->ni_wpa_ie, M_DEVBUF);
942 	if (ni->ni_wme_ie != NULL)
943 		FREE(ni->ni_wme_ie, M_DEVBUF);
944 	IEEE80211_NODE_SAVEQ_DESTROY(ni);
945 	FREE(ni, M_80211_NODE);
946 }
947 
948 static u_int8_t
949 node_getrssi(const struct ieee80211_node *ni)
950 {
951 	return ni->ni_rssi;
952 }
953 
954 static void
955 ieee80211_setup_node(struct ieee80211_node_table *nt,
956 	struct ieee80211_node *ni, const u_int8_t *macaddr)
957 {
958 	struct ieee80211com *ic = nt->nt_ic;
959 	int hash;
960 
961 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
962 		"%s %p<%s> in %s table\n", __func__, ni,
963 		ether_sprintf(macaddr), nt->nt_name);
964 
965 	IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
966 	hash = IEEE80211_NODE_HASH(macaddr);
967 	ieee80211_node_initref(ni);		/* mark referenced */
968 	ni->ni_chan = IEEE80211_CHAN_ANYC;
969 	ni->ni_authmode = IEEE80211_AUTH_OPEN;
970 	ni->ni_txpower = ic->ic_txpowlimit;	/* max power */
971 	ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
972 	ni->ni_inact_reload = nt->nt_inact_init;
973 	ni->ni_inact = ni->ni_inact_reload;
974 	IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
975 
976 	IEEE80211_NODE_LOCK(nt);
977 	TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
978 	LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
979 	ni->ni_table = nt;
980 	ni->ni_ic = ic;
981 	IEEE80211_NODE_UNLOCK(nt);
982 }
983 
984 struct ieee80211_node *
985 ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
986 {
987 	struct ieee80211com *ic = nt->nt_ic;
988 	struct ieee80211_node *ni;
989 
990 	ni = ic->ic_node_alloc(nt);
991 	if (ni != NULL)
992 		ieee80211_setup_node(nt, ni, macaddr);
993 	else
994 		ic->ic_stats.is_rx_nodealloc++;
995 	return ni;
996 }
997 
998 /*
999  * Craft a temporary node suitable for sending a management frame
1000  * to the specified station.  We craft only as much state as we
1001  * need to do the work since the node will be immediately reclaimed
1002  * once the send completes.
1003  */
1004 struct ieee80211_node *
1005 ieee80211_tmp_node(struct ieee80211com *ic, const u_int8_t *macaddr)
1006 {
1007 	struct ieee80211_node *ni;
1008 
1009 	ni = ic->ic_node_alloc(&ic->ic_sta);
1010 	if (ni != NULL) {
1011 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1012 			"%s %p<%s>\n", __func__, ni, ether_sprintf(macaddr));
1013 
1014 		IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
1015 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
1016 		ieee80211_node_initref(ni);		/* mark referenced */
1017 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1018 		/* NB: required by ieee80211_fix_rate */
1019 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
1020 		ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey,
1021 			IEEE80211_KEYIX_NONE);
1022 		/* XXX optimize away */
1023 		IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
1024 
1025 		ni->ni_table = NULL;		/* NB: pedantic */
1026 		ni->ni_ic = ic;
1027 	} else {
1028 		/* XXX msg */
1029 		ic->ic_stats.is_rx_nodealloc++;
1030 	}
1031 	return ni;
1032 }
1033 
1034 struct ieee80211_node *
1035 ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1036 {
1037 	struct ieee80211com *ic = nt->nt_ic;
1038 	struct ieee80211_node *ni;
1039 
1040 	ni = ic->ic_node_alloc(nt);
1041 	if (ni != NULL) {
1042 		ieee80211_setup_node(nt, ni, macaddr);
1043 		/*
1044 		 * Inherit from ic_bss.
1045 		 */
1046 		ni->ni_authmode = ic->ic_bss->ni_authmode;
1047 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1048 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1049 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
1050 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
1051 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1052 	} else
1053 		ic->ic_stats.is_rx_nodealloc++;
1054 	return ni;
1055 }
1056 
1057 static struct ieee80211_node *
1058 #ifdef IEEE80211_DEBUG_REFCNT
1059 _ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1060 	const u_int8_t *macaddr, const char *func, int line)
1061 #else
1062 _ieee80211_find_node(struct ieee80211_node_table *nt,
1063 	const u_int8_t *macaddr)
1064 #endif
1065 {
1066 	struct ieee80211_node *ni;
1067 	int hash;
1068 
1069 	IEEE80211_NODE_LOCK_ASSERT(nt);
1070 
1071 	hash = IEEE80211_NODE_HASH(macaddr);
1072 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1073 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
1074 			ieee80211_ref_node(ni);	/* mark referenced */
1075 #ifdef IEEE80211_DEBUG_REFCNT
1076 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1077 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1078 			    func, line,
1079 			    ni, ether_sprintf(ni->ni_macaddr),
1080 			    ieee80211_node_refcnt(ni));
1081 #endif
1082 			return ni;
1083 		}
1084 	}
1085 	return NULL;
1086 }
1087 #ifdef IEEE80211_DEBUG_REFCNT
1088 #define	_ieee80211_find_node(nt, mac) \
1089 	_ieee80211_find_node_debug(nt, mac, func, line)
1090 #endif
1091 
1092 struct ieee80211_node *
1093 #ifdef IEEE80211_DEBUG_REFCNT
1094 ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1095 	const u_int8_t *macaddr, const char *func, int line)
1096 #else
1097 ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1098 #endif
1099 {
1100 	struct ieee80211_node *ni;
1101 
1102 	IEEE80211_NODE_LOCK(nt);
1103 	ni = _ieee80211_find_node(nt, macaddr);
1104 	IEEE80211_NODE_UNLOCK(nt);
1105 	return ni;
1106 }
1107 
1108 /*
1109  * Fake up a node; this handles node discovery in adhoc mode.
1110  * Note that for the driver's benefit we we treat this like
1111  * an association so the driver has an opportunity to setup
1112  * it's private state.
1113  */
1114 struct ieee80211_node *
1115 ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
1116 	const u_int8_t macaddr[IEEE80211_ADDR_LEN])
1117 {
1118 	struct ieee80211com *ic = nt->nt_ic;
1119 	struct ieee80211_node *ni;
1120 
1121 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1122 	    "%s: mac<%s>\n", __func__, ether_sprintf(macaddr));
1123 	ni = ieee80211_dup_bss(nt, macaddr);
1124 	if (ni != NULL) {
1125 		/* XXX no rate negotiation; just dup */
1126 		ni->ni_rates = ic->ic_bss->ni_rates;
1127 		if (ic->ic_newassoc != NULL)
1128 			ic->ic_newassoc(ni, 1);
1129 		/* XXX not right for 802.1x/WPA */
1130 		ieee80211_node_authorize(ni);
1131 		if (ic->ic_opmode == IEEE80211_M_AHDEMO) {
1132 			/*
1133 			 * Blindly propagate capabilities based on the
1134 			 * local configuration.  In particular this permits
1135 			 * us to use QoS to disable ACK's.
1136 			 */
1137 			if (ic->ic_flags & IEEE80211_F_WME)
1138 				ni->ni_flags |= IEEE80211_NODE_QOS;
1139 		}
1140 	}
1141 	return ni;
1142 }
1143 
1144 #ifdef IEEE80211_DEBUG
1145 static void
1146 dump_probe_beacon(u_int8_t subtype, int isnew,
1147 	const u_int8_t mac[IEEE80211_ADDR_LEN],
1148 	const struct ieee80211_scanparams *sp)
1149 {
1150 
1151 	printf("[%s] %s%s on chan %u (bss chan %u) ",
1152 	    ether_sprintf(mac), isnew ? "new " : "",
1153 	    ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1154 	    sp->chan, sp->bchan);
1155 	ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1156 	printf("\n");
1157 
1158 	if (isnew) {
1159 		printf("[%s] caps 0x%x bintval %u erp 0x%x",
1160 			ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1161 		if (sp->country != NULL) {
1162 #ifdef __FreeBSD__
1163 			printf(" country info %*D",
1164 				sp->country[1], sp->country+2, " ");
1165 #else
1166 			int i;
1167 			printf(" country info");
1168 			for (i = 0; i < sp->country[1]; i++)
1169 				printf(" %02x", sp->country[i+2]);
1170 #endif
1171 		}
1172 		printf("\n");
1173 	}
1174 }
1175 #endif /* IEEE80211_DEBUG */
1176 
1177 static void
1178 saveie(u_int8_t **iep, const u_int8_t *ie)
1179 {
1180 
1181 	if (ie == NULL)
1182 		*iep = NULL;
1183 	else
1184 		ieee80211_saveie(iep, ie);
1185 }
1186 
1187 /*
1188  * Process a beacon or probe response frame.
1189  */
1190 void
1191 ieee80211_add_scan(struct ieee80211com *ic,
1192 	const struct ieee80211_scanparams *sp,
1193 	const struct ieee80211_frame *wh,
1194 	int subtype, int rssi, int rstamp)
1195 {
1196 #define	ISPROBE(_st)	((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
1197 	struct ieee80211_node_table *nt = &ic->ic_scan;
1198 	struct ieee80211_node *ni;
1199 	int newnode = 0;
1200 
1201 	ni = ieee80211_find_node(nt, wh->i_addr2);
1202 	if (ni == NULL) {
1203 		/*
1204 		 * Create a new entry.
1205 		 */
1206 		ni = ic->ic_node_alloc(nt);
1207 		if (ni == NULL) {
1208 			ic->ic_stats.is_rx_nodealloc++;
1209 			return;
1210 		}
1211 		ieee80211_setup_node(nt, ni, wh->i_addr2);
1212 		/*
1213 		 * XXX inherit from ic_bss.
1214 		 */
1215 		ni->ni_authmode = ic->ic_bss->ni_authmode;
1216 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1217 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1218 		ieee80211_set_chan(ic, ni, ic->ic_curchan);
1219 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1220 		newnode = 1;
1221 	}
1222 #ifdef IEEE80211_DEBUG
1223 	if (ieee80211_msg_scan(ic) && (ic->ic_flags & IEEE80211_F_SCAN))
1224 		dump_probe_beacon(subtype, newnode, wh->i_addr2, sp);
1225 #endif
1226 	/* XXX ap beaconing multiple ssid w/ same bssid */
1227 	if (sp->ssid[1] != 0 &&
1228 	    (ISPROBE(subtype) || ni->ni_esslen == 0)) {
1229 		ni->ni_esslen = sp->ssid[1];
1230 		memset(ni->ni_essid, 0, sizeof(ni->ni_essid));
1231 		memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
1232 	}
1233 	ni->ni_scangen = ic->ic_scan.nt_scangen;
1234 	IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
1235 	ni->ni_rssi = rssi;
1236 	ni->ni_rstamp = rstamp;
1237 	memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
1238 	ni->ni_intval = sp->bintval;
1239 	ni->ni_capinfo = sp->capinfo;
1240 	ni->ni_chan = &ic->ic_channels[sp->chan];
1241 	ni->ni_fhdwell = sp->fhdwell;
1242 	ni->ni_fhindex = sp->fhindex;
1243 	ni->ni_erp = sp->erp;
1244 	if (sp->tim != NULL) {
1245 		struct ieee80211_tim_ie *ie =
1246 		    (struct ieee80211_tim_ie *) sp->tim;
1247 
1248 		ni->ni_dtim_count = ie->tim_count;
1249 		ni->ni_dtim_period = ie->tim_period;
1250 	}
1251 	/*
1252 	 * Record the byte offset from the mac header to
1253 	 * the start of the TIM information element for
1254 	 * use by hardware and/or to speedup software
1255 	 * processing of beacon frames.
1256 	 */
1257 	ni->ni_timoff = sp->timoff;
1258 	/*
1259 	 * Record optional information elements that might be
1260 	 * used by applications or drivers.
1261 	 */
1262 	saveie(&ni->ni_wme_ie, sp->wme);
1263 	saveie(&ni->ni_wpa_ie, sp->wpa);
1264 
1265 	/* NB: must be after ni_chan is setup */
1266 	ieee80211_setup_rates(ni, sp->rates, sp->xrates, IEEE80211_F_DOSORT);
1267 
1268 	if (!newnode)
1269 		ieee80211_free_node(ni);
1270 #undef ISPROBE
1271 }
1272 
1273 void
1274 ieee80211_init_neighbor(struct ieee80211_node *ni,
1275 	const struct ieee80211_frame *wh,
1276 	const struct ieee80211_scanparams *sp)
1277 {
1278 
1279 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1280 	    "%s: %p<%s>\n", __func__, ni, ether_sprintf(ni->ni_macaddr));
1281 	ni->ni_esslen = sp->ssid[1];
1282 	memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
1283 	IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
1284 	memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
1285 	ni->ni_intval = sp->bintval;
1286 	ni->ni_capinfo = sp->capinfo;
1287 	ni->ni_chan = ni->ni_ic->ic_curchan;
1288 	ni->ni_fhdwell = sp->fhdwell;
1289 	ni->ni_fhindex = sp->fhindex;
1290 	ni->ni_erp = sp->erp;
1291 	ni->ni_timoff = sp->timoff;
1292 	if (sp->wme != NULL)
1293 		ieee80211_saveie(&ni->ni_wme_ie, sp->wme);
1294 	if (sp->wpa != NULL)
1295 		ieee80211_saveie(&ni->ni_wpa_ie, sp->wpa);
1296 
1297 	/* NB: must be after ni_chan is setup */
1298 	ieee80211_setup_rates(ni, sp->rates, sp->xrates, IEEE80211_F_DOSORT);
1299 }
1300 
1301 /*
1302  * Do node discovery in adhoc mode on receipt of a beacon
1303  * or probe response frame.  Note that for the driver's
1304  * benefit we we treat this like an association so the
1305  * driver has an opportunity to setup it's private state.
1306  */
1307 struct ieee80211_node *
1308 ieee80211_add_neighbor(struct ieee80211com *ic,
1309 	const struct ieee80211_frame *wh,
1310 	const struct ieee80211_scanparams *sp)
1311 {
1312 	struct ieee80211_node *ni;
1313 
1314 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1315 	    "%s: mac<%s>\n", __func__, ether_sprintf(wh->i_addr2));
1316 	ni = ieee80211_dup_bss(&ic->ic_sta, wh->i_addr2);/* XXX alloc_node? */
1317 	if (ni != NULL) {
1318 		ieee80211_init_neighbor(ni, wh, sp);
1319 		if (ic->ic_newassoc != NULL)
1320 			ic->ic_newassoc(ni, 1);
1321 		/* XXX not right for 802.1x/WPA */
1322 		ieee80211_node_authorize(ni);
1323 	}
1324 	return ni;
1325 }
1326 
1327 #define	IS_CTL(wh) \
1328 	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1329 #define	IS_PSPOLL(wh) \
1330 	((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
1331 /*
1332  * Locate the node for sender, track state, and then pass the
1333  * (referenced) node up to the 802.11 layer for its use.  We
1334  * are required to pass some node so we fall back to ic_bss
1335  * when this frame is from an unknown sender.  The 802.11 layer
1336  * knows this means the sender wasn't in the node table and
1337  * acts accordingly.
1338  */
1339 struct ieee80211_node *
1340 #ifdef IEEE80211_DEBUG_REFCNT
1341 ieee80211_find_rxnode_debug(struct ieee80211com *ic,
1342 	const struct ieee80211_frame_min *wh, const char *func, int line)
1343 #else
1344 ieee80211_find_rxnode(struct ieee80211com *ic,
1345 	const struct ieee80211_frame_min *wh)
1346 #endif
1347 {
1348 	struct ieee80211_node_table *nt;
1349 	struct ieee80211_node *ni;
1350 
1351 	/* XXX may want scanned nodes in the neighbor table for adhoc */
1352 	if (ic->ic_opmode == IEEE80211_M_STA ||
1353 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1354 	    (ic->ic_flags & IEEE80211_F_SCAN))
1355 		nt = &ic->ic_scan;
1356 	else
1357 		nt = &ic->ic_sta;
1358 	/* XXX check ic_bss first in station mode */
1359 	/* XXX 4-address frames? */
1360 	IEEE80211_NODE_LOCK(nt);
1361 	if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1362 		ni = _ieee80211_find_node(nt, wh->i_addr1);
1363 	else
1364 		ni = _ieee80211_find_node(nt, wh->i_addr2);
1365 	if (ni == NULL)
1366 		ni = ieee80211_ref_node(ic->ic_bss);
1367 	IEEE80211_NODE_UNLOCK(nt);
1368 
1369 	return ni;
1370 }
1371 
1372 /*
1373  * Like ieee80211_find_rxnode but use the supplied h/w
1374  * key index as a hint to locate the node in the key
1375  * mapping table.  If an entry is present at the key
1376  * index we return it; otherwise do a normal lookup and
1377  * update the mapping table if the station has a unicast
1378  * key assigned to it.
1379  */
1380 struct ieee80211_node *
1381 #ifdef IEEE80211_DEBUG_REFCNT
1382 ieee80211_find_rxnode_withkey_debug(struct ieee80211com *ic,
1383 	const struct ieee80211_frame_min *wh, ieee80211_keyix keyix,
1384 	const char *func, int line)
1385 #else
1386 ieee80211_find_rxnode_withkey(struct ieee80211com *ic,
1387 	const struct ieee80211_frame_min *wh, ieee80211_keyix keyix)
1388 #endif
1389 {
1390 	struct ieee80211_node_table *nt;
1391 	struct ieee80211_node *ni;
1392 
1393 	if (ic->ic_opmode == IEEE80211_M_STA ||
1394 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1395 	    (ic->ic_flags & IEEE80211_F_SCAN))
1396 		nt = &ic->ic_scan;
1397 	else
1398 		nt = &ic->ic_sta;
1399 	IEEE80211_NODE_LOCK(nt);
1400 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax)
1401 		ni = nt->nt_keyixmap[keyix];
1402 	else
1403 		ni = NULL;
1404 	if (ni == NULL) {
1405 		if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1406 			ni = _ieee80211_find_node(nt, wh->i_addr1);
1407 		else
1408 			ni = _ieee80211_find_node(nt, wh->i_addr2);
1409 		if (ni == NULL)
1410 			ni = ieee80211_ref_node(ic->ic_bss);
1411 		if (nt->nt_keyixmap != NULL) {
1412 			/*
1413 			 * If the station has a unicast key cache slot
1414 			 * assigned update the key->node mapping table.
1415 			 */
1416 			keyix = ni->ni_ucastkey.wk_rxkeyix;
1417 			/* XXX can keyixmap[keyix] != NULL? */
1418 			if (keyix < nt->nt_keyixmax &&
1419 			    nt->nt_keyixmap[keyix] == NULL) {
1420 				IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1421 				    "%s: add key map entry %p<%s> refcnt %d\n",
1422 				    __func__, ni, ether_sprintf(ni->ni_macaddr),
1423 				    ieee80211_node_refcnt(ni)+1);
1424 				nt->nt_keyixmap[keyix] = ieee80211_ref_node(ni);
1425 			}
1426 		}
1427 	} else {
1428 		ieee80211_ref_node(ni);
1429 	}
1430 	IEEE80211_NODE_UNLOCK(nt);
1431 
1432 	return ni;
1433 }
1434 #undef IS_PSPOLL
1435 #undef IS_CTL
1436 
1437 /*
1438  * Return a reference to the appropriate node for sending
1439  * a data frame.  This handles node discovery in adhoc networks.
1440  */
1441 struct ieee80211_node *
1442 #ifdef IEEE80211_DEBUG_REFCNT
1443 ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
1444 	const char *func, int line)
1445 #else
1446 ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
1447 #endif
1448 {
1449 	struct ieee80211_node_table *nt = &ic->ic_sta;
1450 	struct ieee80211_node *ni;
1451 
1452 	/*
1453 	 * The destination address should be in the node table
1454 	 * unless this is a multicast/broadcast frame.  We can
1455 	 * also optimize station mode operation, all frames go
1456 	 * to the bss node.
1457 	 */
1458 	/* XXX can't hold lock across dup_bss 'cuz of recursive locking */
1459 	IEEE80211_NODE_LOCK(nt);
1460 	if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
1461 		ni = ieee80211_ref_node(ic->ic_bss);
1462 	else {
1463 		ni = _ieee80211_find_node(nt, macaddr);
1464 		if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
1465 		    (ni != NULL && ni->ni_associd == 0)) {
1466 			/*
1467 			 * Station is not associated; don't permit the
1468 			 * data frame to be sent by returning NULL.  This
1469 			 * is kinda a kludge but the least intrusive way
1470 			 * to add this check into all drivers.
1471 			 */
1472 			ieee80211_unref_node(&ni);	/* NB: null's ni */
1473 		}
1474 	}
1475 	IEEE80211_NODE_UNLOCK(nt);
1476 
1477 	if (ni == NULL) {
1478 		if (ic->ic_opmode == IEEE80211_M_IBSS ||
1479 		    ic->ic_opmode == IEEE80211_M_AHDEMO) {
1480 			/*
1481 			 * In adhoc mode cons up a node for the destination.
1482 			 * Note that we need an additional reference for the
1483 			 * caller to be consistent with _ieee80211_find_node.
1484 			 */
1485 			ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
1486 			if (ni != NULL)
1487 				(void) ieee80211_ref_node(ni);
1488 		} else {
1489 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
1490 				"[%s] no node, discard frame (%s)\n",
1491 				ether_sprintf(macaddr), __func__);
1492 			ic->ic_stats.is_tx_nonode++;
1493 		}
1494 	}
1495 	return ni;
1496 }
1497 
1498 /*
1499  * Like find but search based on the channel too.
1500  */
1501 struct ieee80211_node *
1502 #ifdef IEEE80211_DEBUG_REFCNT
1503 ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
1504 	const u_int8_t *macaddr, struct ieee80211_channel *chan,
1505 	const char *func, int line)
1506 #else
1507 ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
1508 	const u_int8_t *macaddr, struct ieee80211_channel *chan)
1509 #endif
1510 {
1511 	struct ieee80211_node *ni;
1512 	int hash;
1513 
1514 	hash = IEEE80211_NODE_HASH(macaddr);
1515 	IEEE80211_NODE_LOCK(nt);
1516 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1517 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1518 		    ni->ni_chan == chan) {
1519 			ieee80211_ref_node(ni);		/* mark referenced */
1520 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1521 			    REFCNT_LOC, ni, ether_sprintf(ni->ni_macaddr),
1522 			    ieee80211_node_refcnt(ni));
1523 			break;
1524 		}
1525 	}
1526 	IEEE80211_NODE_UNLOCK(nt);
1527 	return ni;
1528 }
1529 
1530 /*
1531  * Like find but search based on the ssid too.
1532  */
1533 struct ieee80211_node *
1534 #ifdef IEEE80211_DEBUG_REFCNT
1535 ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
1536 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
1537 	const char *func, int line)
1538 #else
1539 ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
1540 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
1541 #endif
1542 {
1543 #define	MATCH_SSID(ni, ssid, ssidlen) \
1544 	(ni->ni_esslen == ssidlen && memcmp(ni->ni_essid, ssid, ssidlen) == 0)
1545 	static const u_int8_t zeromac[IEEE80211_ADDR_LEN];
1546 	struct ieee80211com *ic = nt->nt_ic;
1547 	struct ieee80211_node *ni;
1548 	int hash;
1549 
1550 	IEEE80211_NODE_LOCK(nt);
1551 	/*
1552 	 * A mac address that is all zero means match only the ssid;
1553 	 * otherwise we must match both.
1554 	 */
1555 	if (IEEE80211_ADDR_EQ(macaddr, zeromac)) {
1556 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1557 			if (MATCH_SSID(ni, ssid, ssidlen))
1558 				break;
1559 		}
1560 	} else {
1561 		hash = IEEE80211_NODE_HASH(macaddr);
1562 		LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1563 			if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1564 			    MATCH_SSID(ni, ssid, ssidlen))
1565 				break;
1566 		}
1567 	}
1568 	if (ni != NULL) {
1569 		ieee80211_ref_node(ni);	/* mark referenced */
1570 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1571 		     REFCNT_LOC, ni, ether_sprintf(ni->ni_macaddr),
1572 		     ieee80211_node_refcnt(ni));
1573 	}
1574 	IEEE80211_NODE_UNLOCK(nt);
1575 	return ni;
1576 #undef MATCH_SSID
1577 }
1578 
1579 static void
1580 _ieee80211_free_node(struct ieee80211_node *ni)
1581 {
1582 	struct ieee80211com *ic = ni->ni_ic;
1583 	struct ieee80211_node_table *nt = ni->ni_table;
1584 
1585 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1586 		"%s %p<%s> in %s table\n", __func__, ni,
1587 		ether_sprintf(ni->ni_macaddr),
1588 		nt != NULL ? nt->nt_name : "<gone>");
1589 
1590 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1591 	if (nt != NULL) {
1592 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1593 		LIST_REMOVE(ni, ni_hash);
1594 	}
1595 	ic->ic_node_free(ni);
1596 }
1597 
1598 void
1599 #ifdef IEEE80211_DEBUG_REFCNT
1600 ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
1601 #else
1602 ieee80211_free_node(struct ieee80211_node *ni)
1603 #endif
1604 {
1605 	struct ieee80211_node_table *nt = ni->ni_table;
1606 
1607 #ifdef IEEE80211_DEBUG_REFCNT
1608 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1609 		"%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line, ni,
1610 		 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
1611 #endif
1612 	if (nt != NULL) {
1613 		IEEE80211_NODE_LOCK(nt);
1614 		if (ieee80211_node_dectestref(ni)) {
1615 			/*
1616 			 * Last reference, reclaim state.
1617 			 */
1618 			_ieee80211_free_node(ni);
1619 		} else if (ieee80211_node_refcnt(ni) == 1 &&
1620 		    nt->nt_keyixmap != NULL) {
1621 			ieee80211_keyix keyix;
1622 			/*
1623 			 * Check for a last reference in the key mapping table.
1624 			 */
1625 			keyix = ni->ni_ucastkey.wk_rxkeyix;
1626 			if (keyix < nt->nt_keyixmax &&
1627 			    nt->nt_keyixmap[keyix] == ni) {
1628 				IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1629 				    "%s: %p<%s> clear key map entry", __func__,
1630 				    ni, ether_sprintf(ni->ni_macaddr));
1631 				nt->nt_keyixmap[keyix] = NULL;
1632 				ieee80211_node_decref(ni); /* XXX needed? */
1633 				_ieee80211_free_node(ni);
1634 			}
1635 		}
1636 		IEEE80211_NODE_UNLOCK(nt);
1637 	} else {
1638 		if (ieee80211_node_dectestref(ni))
1639 			_ieee80211_free_node(ni);
1640 	}
1641 }
1642 
1643 /*
1644  * Reclaim a unicast key and clear any key cache state.
1645  */
1646 int
1647 ieee80211_node_delucastkey(struct ieee80211_node *ni)
1648 {
1649 	struct ieee80211com *ic = ni->ni_ic;
1650 	struct ieee80211_node_table *nt = &ic->ic_sta;
1651 	struct ieee80211_node *nikey;
1652 	ieee80211_keyix keyix;
1653 	int isowned, status;
1654 
1655 	/*
1656 	 * NB: We must beware of LOR here; deleting the key
1657 	 * can cause the crypto layer to block traffic updates
1658 	 * which can generate a LOR against the node table lock;
1659 	 * grab it here and stash the key index for our use below.
1660 	 *
1661 	 * Must also beware of recursion on the node table lock.
1662 	 * When called from node_cleanup we may already have
1663 	 * the node table lock held.  Unfortunately there's no
1664 	 * way to separate out this path so we must do this
1665 	 * conditionally.
1666 	 */
1667 	isowned = IEEE80211_NODE_IS_LOCKED(nt);
1668 	if (!isowned)
1669 		IEEE80211_NODE_LOCK(nt);
1670 	keyix = ni->ni_ucastkey.wk_rxkeyix;
1671 	status = ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
1672 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax) {
1673 		nikey = nt->nt_keyixmap[keyix];
1674 		nt->nt_keyixmap[keyix] = NULL;;
1675 	} else
1676 		nikey = NULL;
1677 	if (!isowned)
1678 		IEEE80211_NODE_UNLOCK(&ic->ic_sta);
1679 
1680 	if (nikey != NULL) {
1681 		KASSERT(nikey == ni,
1682 			("key map out of sync, ni %p nikey %p", ni, nikey));
1683 		IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1684 			"%s: delete key map entry %p<%s> refcnt %d\n",
1685 			__func__, ni, ether_sprintf(ni->ni_macaddr),
1686 			ieee80211_node_refcnt(ni)-1);
1687 		ieee80211_free_node(ni);
1688 	}
1689 	return status;
1690 }
1691 
1692 /*
1693  * Reclaim a node.  If this is the last reference count then
1694  * do the normal free work.  Otherwise remove it from the node
1695  * table and mark it gone by clearing the back-reference.
1696  */
1697 static void
1698 node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1699 {
1700 	ieee80211_keyix keyix;
1701 
1702 	IEEE80211_NODE_LOCK_ASSERT(nt);
1703 
1704 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1705 		"%s: remove %p<%s> from %s table, refcnt %d\n",
1706 		__func__, ni, ether_sprintf(ni->ni_macaddr),
1707 		nt->nt_name, ieee80211_node_refcnt(ni)-1);
1708 	/*
1709 	 * Clear any entry in the unicast key mapping table.
1710 	 * We need to do it here so rx lookups don't find it
1711 	 * in the mapping table even if it's not in the hash
1712 	 * table.  We cannot depend on the mapping table entry
1713 	 * being cleared because the node may not be free'd.
1714 	 */
1715 	keyix = ni->ni_ucastkey.wk_rxkeyix;
1716 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax &&
1717 	    nt->nt_keyixmap[keyix] == ni) {
1718 		IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1719 			"%s: %p<%s> clear key map entry\n",
1720 			__func__, ni, ether_sprintf(ni->ni_macaddr));
1721 		nt->nt_keyixmap[keyix] = NULL;
1722 		ieee80211_node_decref(ni);	/* NB: don't need free */
1723 	}
1724 	if (!ieee80211_node_dectestref(ni)) {
1725 		/*
1726 		 * Other references are present, just remove the
1727 		 * node from the table so it cannot be found.  When
1728 		 * the references are dropped storage will be
1729 		 * reclaimed.
1730 		 */
1731 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1732 		LIST_REMOVE(ni, ni_hash);
1733 		ni->ni_table = NULL;		/* clear reference */
1734 	} else
1735 		_ieee80211_free_node(ni);
1736 }
1737 
1738 static void
1739 ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
1740 {
1741 	struct ieee80211com *ic = nt->nt_ic;
1742 	struct ieee80211_node *ni;
1743 
1744 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1745 		"%s: free all nodes in %s table\n", __func__, nt->nt_name);
1746 
1747 	while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
1748 		if (ni->ni_associd != 0) {
1749 			if (ic->ic_auth->ia_node_leave != NULL)
1750 				ic->ic_auth->ia_node_leave(ic, ni);
1751 			IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1752 		}
1753 		node_reclaim(nt, ni);
1754 	}
1755 	ieee80211_reset_erp(ic);
1756 }
1757 
1758 static void
1759 ieee80211_free_allnodes(struct ieee80211_node_table *nt)
1760 {
1761 
1762 	IEEE80211_NODE_LOCK(nt);
1763 	ieee80211_free_allnodes_locked(nt);
1764 	IEEE80211_NODE_UNLOCK(nt);
1765 }
1766 
1767 /*
1768  * Timeout entries in the scan cache.
1769  */
1770 static void
1771 ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
1772 {
1773 	struct ieee80211com *ic = nt->nt_ic;
1774 	struct ieee80211_node *ni, *tni;
1775 
1776 	IEEE80211_NODE_LOCK(nt);
1777 	ni = ic->ic_bss;
1778 	/* XXX belongs elsewhere */
1779 	if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
1780 		m_freem(ni->ni_rxfrag[0]);
1781 		ni->ni_rxfrag[0] = NULL;
1782 	}
1783 	TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
1784 		if (ni->ni_inact && --ni->ni_inact == 0) {
1785 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1786 			    "[%s] scan candidate purged from cache "
1787 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1788 			    ieee80211_node_refcnt(ni));
1789 			node_reclaim(nt, ni);
1790 		}
1791 	}
1792 	IEEE80211_NODE_UNLOCK(nt);
1793 
1794 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1795 }
1796 
1797 /*
1798  * Timeout inactive stations and do related housekeeping.
1799  * Note that we cannot hold the node lock while sending a
1800  * frame as this would lead to a LOR.  Instead we use a
1801  * generation number to mark nodes that we've scanned and
1802  * drop the lock and restart a scan if we have to time out
1803  * a node.  Since we are single-threaded by virtue of
1804  * controlling the inactivity timer we can be sure this will
1805  * process each node only once.
1806  */
1807 static void
1808 ieee80211_timeout_stations(struct ieee80211_node_table *nt)
1809 {
1810 	struct ieee80211com *ic = nt->nt_ic;
1811 	struct ieee80211_node *ni;
1812 	u_int gen;
1813 	int isadhoc;
1814 
1815 	isadhoc = (ic->ic_opmode == IEEE80211_M_IBSS ||
1816 		   ic->ic_opmode == IEEE80211_M_AHDEMO);
1817 	IEEE80211_SCAN_LOCK(nt);
1818 	gen = ++nt->nt_scangen;
1819 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1820 		"%s: %s scangen %u\n", __func__, nt->nt_name, gen);
1821 restart:
1822 	IEEE80211_NODE_LOCK(nt);
1823 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1824 		if (ni->ni_scangen == gen)	/* previously handled */
1825 			continue;
1826 		ni->ni_scangen = gen;
1827 		/*
1828 		 * Ignore entries for which have yet to receive an
1829 		 * authentication frame.  These are transient and
1830 		 * will be reclaimed when the last reference to them
1831 		 * goes away (when frame xmits complete).
1832 		 */
1833 		if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
1834 		    (ni->ni_flags & IEEE80211_NODE_AREF) == 0)
1835 			continue;
1836 		/*
1837 		 * Free fragment if not needed anymore
1838 		 * (last fragment older than 1s).
1839 		 * XXX doesn't belong here
1840 		 */
1841 		if (ni->ni_rxfrag[0] != NULL &&
1842 		    ticks > ni->ni_rxfragstamp + hz) {
1843 			m_freem(ni->ni_rxfrag[0]);
1844 			ni->ni_rxfrag[0] = NULL;
1845 		}
1846 		/*
1847 		 * Special case ourself; we may be idle for extended periods
1848 		 * of time and regardless reclaiming our state is wrong.
1849 		 */
1850 		if (ni == ic->ic_bss)
1851 			continue;
1852 		ni->ni_inact--;
1853 		if (ni->ni_associd != 0 || isadhoc) {
1854 			/*
1855 			 * Age frames on the power save queue. The
1856 			 * aging interval is 4 times the listen
1857 			 * interval specified by the station.  This
1858 			 * number is factored into the age calculations
1859 			 * when the frame is placed on the queue.  We
1860 			 * store ages as time differences we can check
1861 			 * and/or adjust only the head of the list.
1862 			 */
1863 			if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
1864 				struct mbuf *m;
1865 				int discard = 0;
1866 
1867 				IEEE80211_NODE_SAVEQ_LOCK(ni);
1868 				while (IF_POLL(&ni->ni_savedq, m) != NULL &&
1869 				     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
1870 IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
1871 					_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
1872 					m_freem(m);
1873 					discard++;
1874 				}
1875 				if (m != NULL)
1876 					M_AGE_SUB(m, IEEE80211_INACT_WAIT);
1877 				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1878 
1879 				if (discard != 0) {
1880 					IEEE80211_DPRINTF(ic,
1881 					    IEEE80211_MSG_POWER,
1882 					    "[%s] discard %u frames for age\n",
1883 					    ether_sprintf(ni->ni_macaddr),
1884 					    discard);
1885 					IEEE80211_NODE_STAT_ADD(ni,
1886 						ps_discard, discard);
1887 					if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
1888 						ic->ic_set_tim(ni, 0);
1889 				}
1890 			}
1891 			/*
1892 			 * Probe the station before time it out.  We
1893 			 * send a null data frame which may not be
1894 			 * universally supported by drivers (need it
1895 			 * for ps-poll support so it should be...).
1896 			 */
1897 			if (0 < ni->ni_inact &&
1898 			    ni->ni_inact <= ic->ic_inact_probe) {
1899 				IEEE80211_NOTE(ic,
1900 				    IEEE80211_MSG_INACT | IEEE80211_MSG_NODE,
1901 				    ni, "%s",
1902 				    "probe station due to inactivity");
1903 				/*
1904 				 * Grab a reference before unlocking the table
1905 				 * so the node cannot be reclaimed before we
1906 				 * send the frame. ieee80211_send_nulldata
1907 				 * understands we've done this and reclaims the
1908 				 * ref for us as needed.
1909 				 */
1910 				ieee80211_ref_node(ni);
1911 				IEEE80211_NODE_UNLOCK(nt);
1912 				ieee80211_send_nulldata(ni);
1913 				/* XXX stat? */
1914 				goto restart;
1915 			}
1916 		}
1917 		if (ni->ni_inact <= 0) {
1918 			IEEE80211_NOTE(ic,
1919 			    IEEE80211_MSG_INACT | IEEE80211_MSG_NODE, ni,
1920 			    "station timed out due to inactivity "
1921 			    "(refcnt %u)", ieee80211_node_refcnt(ni));
1922 			/*
1923 			 * Send a deauthenticate frame and drop the station.
1924 			 * This is somewhat complicated due to reference counts
1925 			 * and locking.  At this point a station will typically
1926 			 * have a reference count of 1.  ieee80211_node_leave
1927 			 * will do a "free" of the node which will drop the
1928 			 * reference count.  But in the meantime a reference
1929 			 * wil be held by the deauth frame.  The actual reclaim
1930 			 * of the node will happen either after the tx is
1931 			 * completed or by ieee80211_node_leave.
1932 			 *
1933 			 * Separately we must drop the node lock before sending
1934 			 * in case the driver takes a lock, as this will result
1935 			 * in  LOR between the node lock and the driver lock.
1936 			 */
1937 			IEEE80211_NODE_UNLOCK(nt);
1938 			if (ni->ni_associd != 0) {
1939 				IEEE80211_SEND_MGMT(ic, ni,
1940 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
1941 				    IEEE80211_REASON_AUTH_EXPIRE);
1942 			}
1943 			ieee80211_node_leave(ic, ni);
1944 			ic->ic_stats.is_node_timeout++;
1945 			goto restart;
1946 		}
1947 	}
1948 	IEEE80211_NODE_UNLOCK(nt);
1949 
1950 	IEEE80211_SCAN_UNLOCK(nt);
1951 
1952 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1953 }
1954 
1955 void
1956 ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
1957 {
1958 	struct ieee80211_node *ni;
1959 	u_int gen;
1960 
1961 	IEEE80211_SCAN_LOCK(nt);
1962 	gen = ++nt->nt_scangen;
1963 restart:
1964 	IEEE80211_NODE_LOCK(nt);
1965 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1966 		if (ni->ni_scangen != gen) {
1967 			ni->ni_scangen = gen;
1968 			(void) ieee80211_ref_node(ni);
1969 			IEEE80211_NODE_UNLOCK(nt);
1970 			(*f)(arg, ni);
1971 			ieee80211_free_node(ni);
1972 			goto restart;
1973 		}
1974 	}
1975 	IEEE80211_NODE_UNLOCK(nt);
1976 
1977 	IEEE80211_SCAN_UNLOCK(nt);
1978 }
1979 
1980 void
1981 ieee80211_dump_node(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1982 {
1983 	printf("0x%p: mac %s refcnt %d\n", ni,
1984 		ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
1985 	printf("\tscangen %u authmode %u flags 0x%x\n",
1986 		ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
1987 	printf("\tassocid 0x%x txpower %u vlan %u\n",
1988 		ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
1989 	printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
1990 		ni->ni_txseqs[0],
1991 		ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
1992 		ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
1993 		ni->ni_rxfragstamp);
1994 	printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
1995 		ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
1996 	printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
1997 		ether_sprintf(ni->ni_bssid),
1998 		ni->ni_esslen, ni->ni_essid,
1999 		ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
2000 	printf("\tfails %u inact %u txrate %u\n",
2001 		ni->ni_fails, ni->ni_inact, ni->ni_txrate);
2002 }
2003 
2004 void
2005 ieee80211_dump_nodes(struct ieee80211_node_table *nt)
2006 {
2007 	ieee80211_iterate_nodes(nt,
2008 		(ieee80211_iter_func *) ieee80211_dump_node, nt);
2009 }
2010 
2011 /*
2012  * Handle a station joining an 11g network.
2013  */
2014 static void
2015 ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
2016 {
2017 
2018 	/*
2019 	 * Station isn't capable of short slot time.  Bump
2020 	 * the count of long slot time stations and disable
2021 	 * use of short slot time.  Note that the actual switch
2022 	 * over to long slot time use may not occur until the
2023 	 * next beacon transmission (per sec. 7.3.1.4 of 11g).
2024 	 */
2025 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
2026 		ic->ic_longslotsta++;
2027 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2028 		    "[%s] station needs long slot time, count %d\n",
2029 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
2030 		/* XXX vap's w/ conflicting needs won't work */
2031 		ieee80211_set_shortslottime(ic, 0);
2032 	}
2033 	/*
2034 	 * If the new station is not an ERP station
2035 	 * then bump the counter and enable protection
2036 	 * if configured.
2037 	 */
2038 	if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
2039 		ic->ic_nonerpsta++;
2040 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2041 		    "[%s] station is !ERP, %d non-ERP stations associated\n",
2042 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
2043 		/*
2044 		 * If protection is configured, enable it.
2045 		 */
2046 		if (ic->ic_protmode != IEEE80211_PROT_NONE) {
2047 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2048 			    "%s: enable use of protection\n", __func__);
2049 			ic->ic_flags |= IEEE80211_F_USEPROT;
2050 		}
2051 		/*
2052 		 * If station does not support short preamble
2053 		 * then we must enable use of Barker preamble.
2054 		 */
2055 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
2056 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2057 			    "[%s] station needs long preamble\n",
2058 			    ether_sprintf(ni->ni_macaddr));
2059 			ic->ic_flags |= IEEE80211_F_USEBARKER;
2060 			ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
2061 		}
2062 		if (ic->ic_nonerpsta == 1)
2063 			ic->ic_flags_ext |= IEEE80211_FEXT_ERPUPDATE;
2064 	} else
2065 		ni->ni_flags |= IEEE80211_NODE_ERP;
2066 }
2067 
2068 void
2069 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
2070 {
2071 	int newassoc;
2072 
2073 	if (ni->ni_associd == 0) {
2074 		u_int16_t aid;
2075 
2076 		/*
2077 		 * It would be good to search the bitmap
2078 		 * more efficiently, but this will do for now.
2079 		 */
2080 		for (aid = 1; aid < ic->ic_max_aid; aid++) {
2081 			if (!IEEE80211_AID_ISSET(aid,
2082 			    ic->ic_aid_bitmap))
2083 				break;
2084 		}
2085 		if (aid >= ic->ic_max_aid) {
2086 			IEEE80211_SEND_MGMT(ic, ni, resp,
2087 			    IEEE80211_REASON_ASSOC_TOOMANY);
2088 			ieee80211_node_leave(ic, ni);
2089 			return;
2090 		}
2091 		ni->ni_associd = aid | 0xc000;
2092 		IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
2093 		ic->ic_sta_assoc++;
2094 		newassoc = 1;
2095 		if (ic->ic_curmode == IEEE80211_MODE_11G)
2096 			ieee80211_node_join_11g(ic, ni);
2097 	} else
2098 		newassoc = 0;
2099 
2100 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
2101 	    "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
2102 	    ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
2103 	    IEEE80211_NODE_AID(ni),
2104 	    ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
2105 	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
2106 	    ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
2107 	    ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
2108 	);
2109 
2110 	/* give driver a chance to setup state like ni_txrate */
2111 	if (ic->ic_newassoc != NULL)
2112 		ic->ic_newassoc(ni, newassoc);
2113 	ni->ni_inact_reload = ic->ic_inact_auth;
2114 	ni->ni_inact = ni->ni_inact_reload;
2115 	IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
2116 	/* tell the authenticator about new station */
2117 	if (ic->ic_auth->ia_node_join != NULL)
2118 		ic->ic_auth->ia_node_join(ic, ni);
2119 	ieee80211_notify_node_join(ic, ni, newassoc);
2120 }
2121 
2122 /*
2123  * Handle a station leaving an 11g network.
2124  */
2125 static void
2126 ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
2127 {
2128 
2129 	KASSERT(ic->ic_curmode == IEEE80211_MODE_11G,
2130 	     ("not in 11g, bss %u:0x%x, curmode %u", ni->ni_chan->ic_freq,
2131 	      ni->ni_chan->ic_flags, ic->ic_curmode));
2132 
2133 	/*
2134 	 * If a long slot station do the slot time bookkeeping.
2135 	 */
2136 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
2137 		KASSERT(ic->ic_longslotsta > 0,
2138 		    ("bogus long slot station count %d", ic->ic_longslotsta));
2139 		ic->ic_longslotsta--;
2140 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2141 		    "[%s] long slot time station leaves, count now %d\n",
2142 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
2143 		if (ic->ic_longslotsta == 0) {
2144 			/*
2145 			 * Re-enable use of short slot time if supported
2146 			 * and not operating in IBSS mode (per spec).
2147 			 */
2148 			if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
2149 			    ic->ic_opmode != IEEE80211_M_IBSS) {
2150 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2151 				    "%s: re-enable use of short slot time\n",
2152 				    __func__);
2153 				ieee80211_set_shortslottime(ic, 1);
2154 			}
2155 		}
2156 	}
2157 	/*
2158 	 * If a non-ERP station do the protection-related bookkeeping.
2159 	 */
2160 	if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
2161 		KASSERT(ic->ic_nonerpsta > 0,
2162 		    ("bogus non-ERP station count %d", ic->ic_nonerpsta));
2163 		ic->ic_nonerpsta--;
2164 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2165 		    "[%s] non-ERP station leaves, count now %d\n",
2166 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
2167 		if (ic->ic_nonerpsta == 0) {
2168 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2169 				"%s: disable use of protection\n", __func__);
2170 			ic->ic_flags &= ~IEEE80211_F_USEPROT;
2171 			/* XXX verify mode? */
2172 			if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
2173 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2174 				    "%s: re-enable use of short preamble\n",
2175 				    __func__);
2176 				ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
2177 				ic->ic_flags &= ~IEEE80211_F_USEBARKER;
2178 			}
2179 			ic->ic_flags_ext |= IEEE80211_FEXT_ERPUPDATE;
2180 		}
2181 	}
2182 }
2183 
2184 /*
2185  * Handle bookkeeping for station deauthentication/disassociation
2186  * when operating as an ap.
2187  */
2188 void
2189 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
2190 {
2191 	struct ieee80211_node_table *nt = ni->ni_table;
2192 
2193 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
2194 	    "[%s] station with aid %d leaves\n",
2195 	    ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
2196 
2197 	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
2198 		ic->ic_opmode == IEEE80211_M_IBSS ||
2199 		ic->ic_opmode == IEEE80211_M_AHDEMO,
2200 		("unexpected operating mode %u", ic->ic_opmode));
2201 	/*
2202 	 * If node wasn't previously associated all
2203 	 * we need to do is reclaim the reference.
2204 	 */
2205 	/* XXX ibss mode bypasses 11g and notification */
2206 	if (ni->ni_associd == 0)
2207 		goto done;
2208 	/*
2209 	 * Tell the authenticator the station is leaving.
2210 	 * Note that we must do this before yanking the
2211 	 * association id as the authenticator uses the
2212 	 * associd to locate it's state block.
2213 	 */
2214 	if (ic->ic_auth->ia_node_leave != NULL)
2215 		ic->ic_auth->ia_node_leave(ic, ni);
2216 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
2217 	ni->ni_associd = 0;
2218 	ic->ic_sta_assoc--;
2219 
2220 	if (ic->ic_curmode == IEEE80211_MODE_11G)
2221 		ieee80211_node_leave_11g(ic, ni);
2222 	/*
2223 	 * Cleanup station state.  In particular clear various
2224 	 * state that might otherwise be reused if the node
2225 	 * is reused before the reference count goes to zero
2226 	 * (and memory is reclaimed).
2227 	 */
2228 	ieee80211_sta_leave(ic, ni);
2229 done:
2230 	/*
2231 	 * Remove the node from any table it's recorded in and
2232 	 * drop the caller's reference.  Removal from the table
2233 	 * is important to insure the node is not reprocessed
2234 	 * for inactivity.
2235 	 */
2236 	if (nt != NULL) {
2237 		IEEE80211_NODE_LOCK(nt);
2238 		node_reclaim(nt, ni);
2239 		IEEE80211_NODE_UNLOCK(nt);
2240 	} else
2241 		ieee80211_free_node(ni);
2242 }
2243 
2244 u_int8_t
2245 ieee80211_getrssi(struct ieee80211com *ic)
2246 {
2247 #define	NZ(x)	((x) == 0 ? 1 : (x))
2248 	struct ieee80211_node_table *nt = &ic->ic_sta;
2249 	u_int32_t rssi_samples, rssi_total;
2250 	struct ieee80211_node *ni;
2251 
2252 	rssi_total = 0;
2253 	rssi_samples = 0;
2254 	switch (ic->ic_opmode) {
2255 	case IEEE80211_M_IBSS:		/* average of all ibss neighbors */
2256 		/* XXX locking */
2257 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
2258 			if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
2259 				rssi_samples++;
2260 				rssi_total += ic->ic_node_getrssi(ni);
2261 			}
2262 		break;
2263 	case IEEE80211_M_AHDEMO:	/* average of all neighbors */
2264 		/* XXX locking */
2265 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
2266 			rssi_samples++;
2267 			rssi_total += ic->ic_node_getrssi(ni);
2268 		}
2269 		break;
2270 	case IEEE80211_M_HOSTAP:	/* average of all associated stations */
2271 		/* XXX locking */
2272 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
2273 			if (IEEE80211_AID(ni->ni_associd) != 0) {
2274 				rssi_samples++;
2275 				rssi_total += ic->ic_node_getrssi(ni);
2276 			}
2277 		break;
2278 	case IEEE80211_M_MONITOR:	/* XXX */
2279 	case IEEE80211_M_STA:		/* use stats from associated ap */
2280 	default:
2281 		if (ic->ic_bss != NULL)
2282 			rssi_total = ic->ic_node_getrssi(ic->ic_bss);
2283 		rssi_samples = 1;
2284 		break;
2285 	}
2286 	return rssi_total / NZ(rssi_samples);
2287 #undef NZ
2288 }
2289 
2290 /*
2291  * Indicate whether there are frames queued for a station in power-save mode.
2292  */
2293 static void
2294 ieee80211_set_tim(struct ieee80211_node *ni, int set)
2295 {
2296 	struct ieee80211com *ic = ni->ni_ic;
2297 	u_int16_t aid;
2298 
2299 	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
2300 		ic->ic_opmode == IEEE80211_M_IBSS,
2301 		("operating mode %u", ic->ic_opmode));
2302 
2303 	aid = IEEE80211_AID(ni->ni_associd);
2304 	KASSERT(aid < ic->ic_max_aid,
2305 		("bogus aid %u, max %u", aid, ic->ic_max_aid));
2306 
2307 	IEEE80211_BEACON_LOCK(ic);
2308 	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
2309 		if (set) {
2310 			setbit(ic->ic_tim_bitmap, aid);
2311 			ic->ic_ps_pending++;
2312 		} else {
2313 			clrbit(ic->ic_tim_bitmap, aid);
2314 			ic->ic_ps_pending--;
2315 		}
2316 		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
2317 	}
2318 	IEEE80211_BEACON_UNLOCK(ic);
2319 }
2320 
2321 /*
2322  * Node table support.
2323  */
2324 
2325 static void
2326 ieee80211_node_table_init(struct ieee80211com *ic,
2327 	struct ieee80211_node_table *nt,
2328 	const char *name, int inact, int keyixmax,
2329 	void (*timeout)(struct ieee80211_node_table *))
2330 {
2331 
2332 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
2333 		"%s %s table, inact %u\n", __func__, name, inact);
2334 
2335 	nt->nt_ic = ic;
2336 	/* XXX need unit */
2337 	IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
2338 	IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
2339 	TAILQ_INIT(&nt->nt_node);
2340 	nt->nt_name = name;
2341 	nt->nt_scangen = 1;
2342 	nt->nt_inact_init = inact;
2343 	nt->nt_timeout = timeout;
2344 	nt->nt_keyixmax = keyixmax;
2345 	if (nt->nt_keyixmax > 0) {
2346 		MALLOC(nt->nt_keyixmap, struct ieee80211_node **,
2347 			keyixmax * sizeof(struct ieee80211_node *),
2348 			M_80211_NODE, M_NOWAIT | M_ZERO);
2349 		if (nt->nt_keyixmap == NULL)
2350 			if_printf(ic->ic_ifp,
2351 			    "Cannot allocate key index map with %u entries\n",
2352 			    keyixmax);
2353 	} else
2354 		nt->nt_keyixmap = NULL;
2355 }
2356 
2357 void
2358 ieee80211_node_table_reset(struct ieee80211_node_table *nt)
2359 {
2360 
2361 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2362 		"%s %s table\n", __func__, nt->nt_name);
2363 
2364 	IEEE80211_NODE_LOCK(nt);
2365 	nt->nt_inact_timer = 0;
2366 	ieee80211_free_allnodes_locked(nt);
2367 	IEEE80211_NODE_UNLOCK(nt);
2368 }
2369 
2370 static void
2371 ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
2372 {
2373 
2374 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2375 		"%s %s table\n", __func__, nt->nt_name);
2376 
2377 	IEEE80211_NODE_LOCK(nt);
2378 	ieee80211_free_allnodes_locked(nt);
2379 	if (nt->nt_keyixmap != NULL) {
2380 		/* XXX verify all entries are NULL */
2381 		int i;
2382 		for (i = 0; i < nt->nt_keyixmax; i++)
2383 			if (nt->nt_keyixmap[i] != NULL)
2384 				printf("%s: %s[%u] still active\n", __func__,
2385 					nt->nt_name, i);
2386 		FREE(nt->nt_keyixmap, M_80211_NODE);
2387 		nt->nt_keyixmap = NULL;
2388 	}
2389 	IEEE80211_SCAN_LOCK_DESTROY(nt);
2390 	IEEE80211_NODE_LOCK_DESTROY(nt);
2391 }
2392