xref: /freebsd/sys/net80211/ieee80211_node.c (revision c0b9f4fe659b6839541970eb5675e57f4d814969)
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 static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
63 static void node_cleanup(struct ieee80211_node *);
64 static void node_free(struct ieee80211_node *);
65 static u_int8_t node_getrssi(const struct ieee80211_node *);
66 
67 static void ieee80211_setup_node(struct ieee80211_node_table *,
68 		struct ieee80211_node *, const u_int8_t *);
69 static void _ieee80211_free_node(struct ieee80211_node *);
70 static void ieee80211_free_allnodes(struct ieee80211_node_table *);
71 
72 static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
73 static void ieee80211_timeout_stations(struct ieee80211_node_table *);
74 
75 static void ieee80211_set_tim(struct ieee80211_node *, int set);
76 
77 static void ieee80211_node_table_init(struct ieee80211com *ic,
78 	struct ieee80211_node_table *nt, const char *name,
79 	int inact, int keyixmax,
80 	void (*timeout)(struct ieee80211_node_table *));
81 static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
82 
83 MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
84 
85 void
86 ieee80211_node_attach(struct ieee80211com *ic)
87 {
88 
89 	ic->ic_node_alloc = node_alloc;
90 	ic->ic_node_free = node_free;
91 	ic->ic_node_cleanup = node_cleanup;
92 	ic->ic_node_getrssi = node_getrssi;
93 
94 	/* default station inactivity timer setings */
95 	ic->ic_inact_init = IEEE80211_INACT_INIT;
96 	ic->ic_inact_auth = IEEE80211_INACT_AUTH;
97 	ic->ic_inact_run = IEEE80211_INACT_RUN;
98 	ic->ic_inact_probe = IEEE80211_INACT_PROBE;
99 
100 	/* NB: driver should override */
101 	ic->ic_max_aid = IEEE80211_AID_DEF;
102 	ic->ic_set_tim = ieee80211_set_tim;
103 }
104 
105 void
106 ieee80211_node_lateattach(struct ieee80211com *ic)
107 {
108 	struct ieee80211_rsnparms *rsn;
109 
110 	if (ic->ic_max_aid > IEEE80211_AID_MAX)
111 		ic->ic_max_aid = IEEE80211_AID_MAX;
112 	MALLOC(ic->ic_aid_bitmap, u_int32_t *,
113 		howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
114 		M_DEVBUF, M_NOWAIT | M_ZERO);
115 	if (ic->ic_aid_bitmap == NULL) {
116 		/* XXX no way to recover */
117 		printf("%s: no memory for AID bitmap!\n", __func__);
118 		ic->ic_max_aid = 0;
119 	}
120 
121 	/* XXX defer until using hostap/ibss mode */
122 	ic->ic_tim_len = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
123 	MALLOC(ic->ic_tim_bitmap, u_int8_t *, ic->ic_tim_len,
124 		M_DEVBUF, M_NOWAIT | M_ZERO);
125 	if (ic->ic_tim_bitmap == NULL) {
126 		/* XXX no way to recover */
127 		printf("%s: no memory for TIM bitmap!\n", __func__);
128 	}
129 
130 	ieee80211_node_table_init(ic, &ic->ic_sta, "station",
131 		IEEE80211_INACT_INIT, ic->ic_crypto.cs_max_keyix,
132 		ieee80211_timeout_stations);
133 	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
134 		IEEE80211_INACT_SCAN, 0,
135 		ieee80211_timeout_scan_candidates);
136 
137 	ieee80211_reset_bss(ic);
138 	/*
139 	 * Setup "global settings" in the bss node so that
140 	 * each new station automatically inherits them.
141 	 */
142 	rsn = &ic->ic_bss->ni_rsn;
143 	/* WEP, TKIP, and AES-CCM are always supported */
144 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
145 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
146 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
147 	if (ic->ic_caps & IEEE80211_C_AES)
148 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
149 	if (ic->ic_caps & IEEE80211_C_CKIP)
150 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
151 	/*
152 	 * Default unicast cipher to WEP for 802.1x use.  If
153 	 * WPA is enabled the management code will set these
154 	 * values to reflect.
155 	 */
156 	rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
157 	rsn->rsn_ucastkeylen = 104 / NBBY;
158 	/*
159 	 * WPA says the multicast cipher is the lowest unicast
160 	 * cipher supported.  But we skip WEP which would
161 	 * otherwise be used based on this criteria.
162 	 */
163 	rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
164 	rsn->rsn_mcastkeylen = 128 / NBBY;
165 
166 	/*
167 	 * We support both WPA-PSK and 802.1x; the one used
168 	 * is determined by the authentication mode and the
169 	 * setting of the PSK state.
170 	 */
171 	rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
172 	rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
173 
174 	ic->ic_auth = ieee80211_authenticator_get(ic->ic_bss->ni_authmode);
175 }
176 
177 void
178 ieee80211_node_detach(struct ieee80211com *ic)
179 {
180 
181 	if (ic->ic_bss != NULL) {
182 		ieee80211_free_node(ic->ic_bss);
183 		ic->ic_bss = NULL;
184 	}
185 	ieee80211_node_table_cleanup(&ic->ic_scan);
186 	ieee80211_node_table_cleanup(&ic->ic_sta);
187 	if (ic->ic_aid_bitmap != NULL) {
188 		FREE(ic->ic_aid_bitmap, M_DEVBUF);
189 		ic->ic_aid_bitmap = NULL;
190 	}
191 	if (ic->ic_tim_bitmap != NULL) {
192 		FREE(ic->ic_tim_bitmap, M_DEVBUF);
193 		ic->ic_tim_bitmap = NULL;
194 	}
195 }
196 
197 /*
198  * Port authorize/unauthorize interfaces for use by an authenticator.
199  */
200 
201 void
202 ieee80211_node_authorize(struct ieee80211_node *ni)
203 {
204 	struct ieee80211com *ic = ni->ni_ic;
205 
206 	ni->ni_flags |= IEEE80211_NODE_AUTH;
207 	ni->ni_inact_reload = ic->ic_inact_run;
208 }
209 
210 void
211 ieee80211_node_unauthorize(struct ieee80211_node *ni)
212 {
213 	ni->ni_flags &= ~IEEE80211_NODE_AUTH;
214 }
215 
216 /*
217  * Set/change the channel.  The rate set is also updated as
218  * to insure a consistent view by drivers.
219  */
220 static void
221 ieee80211_set_chan(struct ieee80211com *ic,
222 	struct ieee80211_node *ni, struct ieee80211_channel *chan)
223 {
224 	if (chan == IEEE80211_CHAN_ANYC)	/* XXX while scanning */
225 		chan = ic->ic_curchan;
226 	ni->ni_chan = chan;
227 	ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
228 }
229 
230 /*
231  * AP scanning support.
232  */
233 
234 #ifdef IEEE80211_DEBUG
235 static void
236 dump_chanlist(const u_char chans[])
237 {
238 	const char *sep;
239 	int i;
240 
241 	sep = " ";
242 	for (i = 0; i < IEEE80211_CHAN_MAX; i++)
243 		if (isset(chans, i)) {
244 			printf("%s%u", sep, i);
245 			sep = ", ";
246 		}
247 }
248 #endif /* IEEE80211_DEBUG */
249 
250 /*
251  * Initialize the channel set to scan based on the
252  * of available channels and the current PHY mode.
253  */
254 static void
255 ieee80211_reset_scan(struct ieee80211com *ic)
256 {
257 
258 	/* XXX ic_des_chan should be handled with ic_chan_active */
259 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
260 		memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
261 		setbit(ic->ic_chan_scan,
262 			ieee80211_chan2ieee(ic, ic->ic_des_chan));
263 	} else
264 		memcpy(ic->ic_chan_scan, ic->ic_chan_active,
265 			sizeof(ic->ic_chan_active));
266 #ifdef IEEE80211_DEBUG
267 	if (ieee80211_msg_scan(ic)) {
268 		printf("%s: scan set:", __func__);
269 		dump_chanlist(ic->ic_chan_scan);
270 		printf(" start chan %u\n",
271 			ieee80211_chan2ieee(ic, ic->ic_curchan));
272 	}
273 #endif /* IEEE80211_DEBUG */
274 }
275 
276 /*
277  * Begin an active scan.
278  */
279 void
280 ieee80211_begin_scan(struct ieee80211com *ic, int reset)
281 {
282 
283 	ic->ic_scan.nt_scangen++;
284 	/*
285 	 * In all but hostap mode scanning starts off in
286 	 * an active mode before switching to passive.
287 	 */
288 	if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
289 		ic->ic_flags |= IEEE80211_F_ASCAN;
290 		ic->ic_stats.is_scan_active++;
291 	} else
292 		ic->ic_stats.is_scan_passive++;
293 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
294 		"begin %s scan in %s mode, scangen %u\n",
295 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
296 		ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
297 	/*
298 	 * Clear scan state and flush any previously seen AP's.
299 	 */
300 	ieee80211_reset_scan(ic);
301 	if (reset)
302 		ieee80211_free_allnodes(&ic->ic_scan);
303 
304 	ic->ic_flags |= IEEE80211_F_SCAN;
305 
306 	/* Scan the next channel. */
307 	ieee80211_next_scan(ic);
308 }
309 
310 /*
311  * Switch to the next channel marked for scanning.
312  */
313 int
314 ieee80211_next_scan(struct ieee80211com *ic)
315 {
316 	struct ieee80211_channel *chan;
317 
318 	/*
319 	 * Insure any previous mgt frame timeouts don't fire.
320 	 * This assumes the driver does the right thing in
321 	 * flushing anything queued in the driver and below.
322 	 */
323 	ic->ic_mgt_timer = 0;
324 
325 	chan = ic->ic_curchan;
326 	do {
327 		if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
328 			chan = &ic->ic_channels[0];
329 		if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
330 			clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
331 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
332 			    "%s: chan %d->%d\n", __func__,
333 			    ieee80211_chan2ieee(ic, ic->ic_curchan),
334 			    ieee80211_chan2ieee(ic, chan));
335 			ic->ic_curchan = chan;
336 			/*
337 			 * XXX drivers should do this as needed,
338 			 * XXX for now maintain compatibility
339 			 */
340 			ic->ic_bss->ni_rates =
341 				ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
342 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
343 			return 1;
344 		}
345 	} while (chan != ic->ic_curchan);
346 	ieee80211_end_scan(ic);
347 	return 0;
348 }
349 
350 static __inline void
351 copy_bss(struct ieee80211_node *nbss, const struct ieee80211_node *obss)
352 {
353 	/* propagate useful state */
354 	nbss->ni_authmode = obss->ni_authmode;
355 	nbss->ni_txpower = obss->ni_txpower;
356 	nbss->ni_vlan = obss->ni_vlan;
357 	nbss->ni_rsn = obss->ni_rsn;
358 	/* XXX statistics? */
359 }
360 
361 void
362 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
363 {
364 	struct ieee80211_node_table *nt;
365 	struct ieee80211_node *ni;
366 
367 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
368 		"%s: creating ibss\n", __func__);
369 
370 	/*
371 	 * Create the station/neighbor table.  Note that for adhoc
372 	 * mode we make the initial inactivity timer longer since
373 	 * we create nodes only through discovery and they typically
374 	 * are long-lived associations.
375 	 */
376 	nt = &ic->ic_sta;
377 	IEEE80211_NODE_LOCK(nt);
378 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
379 		nt->nt_name = "station";
380 		nt->nt_inact_init = ic->ic_inact_init;
381 	} else {
382 		nt->nt_name = "neighbor";
383 		nt->nt_inact_init = ic->ic_inact_run;
384 	}
385 	IEEE80211_NODE_UNLOCK(nt);
386 
387 	ni = ieee80211_alloc_node(&ic->ic_sta, ic->ic_myaddr);
388 	if (ni == NULL) {
389 		/* XXX recovery? */
390 		return;
391 	}
392 	IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
393 	ni->ni_esslen = ic->ic_des_esslen;
394 	memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
395 	copy_bss(ni, ic->ic_bss);
396 	ni->ni_intval = ic->ic_bintval;
397 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
398 		ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
399 	if (ic->ic_phytype == IEEE80211_T_FH) {
400 		ni->ni_fhdwell = 200;	/* XXX */
401 		ni->ni_fhindex = 1;
402 	}
403 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
404 		ic->ic_flags |= IEEE80211_F_SIBSS;
405 		ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;	/* XXX */
406 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
407 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
408 		else
409 			ni->ni_bssid[0] |= 0x02;	/* local bit for IBSS */
410 	} else if (ic->ic_opmode == IEEE80211_M_AHDEMO) {
411 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
412 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
413 		else
414 			memset(ni->ni_bssid, 0, IEEE80211_ADDR_LEN);
415 	}
416 	/*
417 	 * Fix the channel and related attributes.
418 	 */
419 	ieee80211_set_chan(ic, ni, chan);
420 	ic->ic_curchan = chan;
421 	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
422 	/*
423 	 * Do mode-specific rate setup.
424 	 */
425 	if (ic->ic_curmode == IEEE80211_MODE_11G) {
426 		/*
427 		 * Use a mixed 11b/11g rate set.
428 		 */
429 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
430 	} else if (ic->ic_curmode == IEEE80211_MODE_11B) {
431 		/*
432 		 * Force pure 11b rate set.
433 		 */
434 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
435 	}
436 
437 	(void) ieee80211_sta_join(ic, ieee80211_ref_node(ni));
438 }
439 
440 void
441 ieee80211_reset_bss(struct ieee80211com *ic)
442 {
443 	struct ieee80211_node *ni, *obss;
444 
445 	ieee80211_node_table_reset(&ic->ic_scan);
446 	ieee80211_node_table_reset(&ic->ic_sta);
447 
448 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
449 	KASSERT(ni != NULL, ("unable to setup inital BSS node"));
450 	obss = ic->ic_bss;
451 	ic->ic_bss = ieee80211_ref_node(ni);
452 	if (obss != NULL) {
453 		copy_bss(ni, obss);
454 		ni->ni_intval = ic->ic_bintval;
455 		ieee80211_free_node(obss);
456 	}
457 }
458 
459 /* XXX tunable */
460 #define	STA_FAILS_MAX	2		/* assoc failures before ignored */
461 
462 static int
463 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
464 {
465         u_int8_t rate;
466         int fail;
467 
468 	fail = 0;
469 	if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
470 		fail |= 0x01;
471 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
472 	    ni->ni_chan != ic->ic_des_chan)
473 		fail |= 0x01;
474 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
475 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
476 			fail |= 0x02;
477 	} else {
478 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
479 			fail |= 0x02;
480 	}
481 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
482 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
483 			fail |= 0x04;
484 	} else {
485 		/* XXX does this mean privacy is supported or required? */
486 		if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
487 			fail |= 0x04;
488 	}
489 	rate = ieee80211_fix_rate(ni, IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
490 	if (rate & IEEE80211_RATE_BASIC)
491 		fail |= 0x08;
492 	if (ic->ic_des_esslen != 0 &&
493 	    (ni->ni_esslen != ic->ic_des_esslen ||
494 	     memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
495 		fail |= 0x10;
496 	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
497 	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
498 		fail |= 0x20;
499 	if (ni->ni_fails >= STA_FAILS_MAX)
500 		fail |= 0x40;
501 #ifdef IEEE80211_DEBUG
502 	if (ieee80211_msg_scan(ic)) {
503 		printf(" %c %s",
504 		    fail & 0x40 ? '=' : fail & 0x80 ? '^' : fail ? '-' : '+',
505 		    ether_sprintf(ni->ni_macaddr));
506 		printf(" %s%c", ether_sprintf(ni->ni_bssid),
507 		    fail & 0x20 ? '!' : ' ');
508 		printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
509 			fail & 0x01 ? '!' : ' ');
510 		printf(" %+4d", ni->ni_rssi);
511 		printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
512 		    fail & 0x08 ? '!' : ' ');
513 		printf(" %4s%c",
514 		    (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
515 		    (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
516 		    "????",
517 		    fail & 0x02 ? '!' : ' ');
518 		printf(" %3s%c ",
519 		    (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
520 		    "wep" : "no",
521 		    fail & 0x04 ? '!' : ' ');
522 		ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
523 		printf("%s\n", fail & 0x10 ? "!" : "");
524 	}
525 #endif
526 	return fail;
527 }
528 
529 static __inline u_int8_t
530 maxrate(const struct ieee80211_node *ni)
531 {
532 	const struct ieee80211_rateset *rs = &ni->ni_rates;
533 	/* NB: assumes rate set is sorted (happens on frame receive) */
534 	return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
535 }
536 
537 /*
538  * Compare the capabilities of two nodes and decide which is
539  * more desirable (return >0 if a is considered better).  Note
540  * that we assume compatibility/usability has already been checked
541  * so we don't need to (e.g. validate whether privacy is supported).
542  * Used to select the best scan candidate for association in a BSS.
543  */
544 static int
545 ieee80211_node_compare(struct ieee80211com *ic,
546 		       const struct ieee80211_node *a,
547 		       const struct ieee80211_node *b)
548 {
549 	u_int8_t maxa, maxb;
550 	u_int8_t rssia, rssib;
551 	int weight;
552 
553 	/* privacy support preferred */
554 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
555 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
556 		return 1;
557 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
558 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
559 		return -1;
560 
561 	/* compare count of previous failures */
562 	weight = b->ni_fails - a->ni_fails;
563 	if (abs(weight) > 1)
564 		return weight;
565 
566 	rssia = ic->ic_node_getrssi(a);
567 	rssib = ic->ic_node_getrssi(b);
568 	if (abs(rssib - rssia) < 5) {
569 		/* best/max rate preferred if signal level close enough XXX */
570 		maxa = maxrate(a);
571 		maxb = maxrate(b);
572 		if (maxa != maxb)
573 			return maxa - maxb;
574 		/* XXX use freq for channel preference */
575 		/* for now just prefer 5Ghz band to all other bands */
576 		if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
577 		   !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
578 			return 1;
579 		if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
580 		     IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
581 			return -1;
582 	}
583 	/* all things being equal, use signal level */
584 	return rssia - rssib;
585 }
586 
587 /*
588  * Mark an ongoing scan stopped.
589  */
590 void
591 ieee80211_cancel_scan(struct ieee80211com *ic)
592 {
593 
594 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
595 		__func__,
596 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
597 
598 	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
599 }
600 
601 /*
602  * Complete a scan of potential channels.
603  */
604 void
605 ieee80211_end_scan(struct ieee80211com *ic)
606 {
607 	struct ieee80211_node_table *nt = &ic->ic_scan;
608 	struct ieee80211_node *ni, *selbs;
609 
610 	ieee80211_cancel_scan(ic);
611 	ieee80211_notify_scan_done(ic);
612 
613 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
614 		u_int8_t maxrssi[IEEE80211_CHAN_MAX];	/* XXX off stack? */
615 		int i, bestchan;
616 		u_int8_t rssi;
617 
618 		/*
619 		 * The passive scan to look for existing AP's completed,
620 		 * select a channel to camp on.  Identify the channels
621 		 * that already have one or more AP's and try to locate
622 		 * an unoccupied one.  If that fails, pick a channel that
623 		 * looks to be quietest.
624 		 */
625 		memset(maxrssi, 0, sizeof(maxrssi));
626 		IEEE80211_NODE_LOCK(nt);
627 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
628 			rssi = ic->ic_node_getrssi(ni);
629 			i = ieee80211_chan2ieee(ic, ni->ni_chan);
630 			if (rssi > maxrssi[i])
631 				maxrssi[i] = rssi;
632 		}
633 		IEEE80211_NODE_UNLOCK(nt);
634 		/* XXX select channel more intelligently */
635 		bestchan = -1;
636 		for (i = 0; i < IEEE80211_CHAN_MAX; i++)
637 			if (isset(ic->ic_chan_active, i)) {
638 				/*
639 				 * If the channel is unoccupied the max rssi
640 				 * should be zero; just take it.  Otherwise
641 				 * track the channel with the lowest rssi and
642 				 * use that when all channels appear occupied.
643 				 */
644 				if (maxrssi[i] == 0) {
645 					bestchan = i;
646 					break;
647 				}
648 				if (bestchan == -1 ||
649 				    maxrssi[i] < maxrssi[bestchan])
650 					bestchan = i;
651 			}
652 		if (bestchan != -1) {
653 			ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
654 			return;
655 		}
656 		/* no suitable channel, should not happen */
657 	}
658 
659 	/*
660 	 * When manually sequencing the state machine; scan just once
661 	 * regardless of whether we have a candidate or not.  The
662 	 * controlling application is expected to setup state and
663 	 * initiate an association.
664 	 */
665 	if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
666 		return;
667 	/*
668 	 * Automatic sequencing; look for a candidate and
669 	 * if found join the network.
670 	 */
671 	/* NB: unlocked read should be ok */
672 	if (TAILQ_FIRST(&nt->nt_node) == NULL) {
673 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
674 			"%s: no scan candidate\n", __func__);
675   notfound:
676 		if (ic->ic_opmode == IEEE80211_M_IBSS &&
677 		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
678 		    ic->ic_des_esslen != 0) {
679 			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
680 			return;
681 		}
682 		/*
683 		 * Decrement the failure counts so entries will be
684 		 * reconsidered the next time around.  We really want
685 		 * to do this only for sta's where we've previously
686 		 * had some success.
687 		 */
688 		IEEE80211_NODE_LOCK(nt);
689 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
690 			if (ni->ni_fails)
691 				ni->ni_fails--;
692 		IEEE80211_NODE_UNLOCK(nt);
693 		/*
694 		 * Reset the list of channels to scan and start again.
695 		 */
696 		ieee80211_reset_scan(ic);
697 		ic->ic_flags |= IEEE80211_F_SCAN;
698 		ieee80211_next_scan(ic);
699 		return;
700 	}
701 	selbs = NULL;
702 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
703 	    "macaddr          bssid         chan  rssi rate flag  wep  essid");
704 	IEEE80211_NODE_LOCK(nt);
705 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
706 		if (ieee80211_match_bss(ic, ni) == 0) {
707 			if (selbs == NULL)
708 				selbs = ni;
709 			else if (ieee80211_node_compare(ic, ni, selbs) > 0)
710 				selbs = ni;
711 		}
712 	}
713 	if (selbs != NULL)		/* NB: grab ref while dropping lock */
714 		(void) ieee80211_ref_node(selbs);
715 	IEEE80211_NODE_UNLOCK(nt);
716 	if (selbs == NULL)
717 		goto notfound;
718 	if (!ieee80211_sta_join(ic, selbs)) {
719 		ieee80211_free_node(selbs);
720 		goto notfound;
721 	}
722 }
723 
724 /*
725  * Handle 802.11 ad hoc network merge.  The
726  * convention, set by the Wireless Ethernet Compatibility Alliance
727  * (WECA), is that an 802.11 station will change its BSSID to match
728  * the "oldest" 802.11 ad hoc network, on the same channel, that
729  * has the station's desired SSID.  The "oldest" 802.11 network
730  * sends beacons with the greatest TSF timestamp.
731  *
732  * The caller is assumed to validate TSF's before attempting a merge.
733  *
734  * Return !0 if the BSSID changed, 0 otherwise.
735  */
736 int
737 ieee80211_ibss_merge(struct ieee80211_node *ni)
738 {
739 	struct ieee80211com *ic = ni->ni_ic;
740 
741 	if (ni == ic->ic_bss ||
742 	    IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
743 		/* unchanged, nothing to do */
744 		return 0;
745 	}
746 	if (ieee80211_match_bss(ic, ni) != 0) {	/* capabilities mismatch */
747 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
748 		    "%s: merge failed, capabilities mismatch\n", __func__);
749 		ic->ic_stats.is_ibss_capmismatch++;
750 		return 0;
751 	}
752 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
753 		"%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
754 		ether_sprintf(ni->ni_bssid),
755 		ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
756 		ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
757 		ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
758 	);
759 	return ieee80211_sta_join(ic, ieee80211_ref_node(ni));
760 }
761 
762 /*
763  * Join the specified IBSS/BSS network.  The node is assumed to
764  * be passed in with a held reference.
765  */
766 int
767 ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
768 {
769 	struct ieee80211_node *obss;
770 
771 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
772 		struct ieee80211_node_table *nt;
773 		/*
774 		 * Delete unusable rates; we've already checked
775 		 * that the negotiated rate set is acceptable.
776 		 */
777 		ieee80211_fix_rate(selbs, IEEE80211_F_DODEL);
778 		/*
779 		 * Fillin the neighbor table; it will already
780 		 * exist if we are simply switching mastership.
781 		 * XXX ic_sta always setup so this is unnecessary?
782 		 */
783 		nt = &ic->ic_sta;
784 		IEEE80211_NODE_LOCK(nt);
785 		nt->nt_name = "neighbor";
786 		nt->nt_inact_init = ic->ic_inact_run;
787 		IEEE80211_NODE_UNLOCK(nt);
788 	}
789 
790 	/*
791 	 * Committed to selbs, setup state.
792 	 */
793 	obss = ic->ic_bss;
794 	ic->ic_bss = selbs;		/* NB: caller assumed to bump refcnt */
795 	if (obss != NULL) {
796 		copy_bss(selbs, obss);
797 		ieee80211_free_node(obss);
798 	}
799 	/*
800 	 * Set the erp state (mostly the slot time) to deal with
801 	 * the auto-select case; this should be redundant if the
802 	 * mode is locked.
803 	 */
804 	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
805 	ic->ic_curchan = selbs->ni_chan;
806 	ieee80211_reset_erp(ic);
807 	ieee80211_wme_initparams(ic);
808 
809 	if (ic->ic_opmode == IEEE80211_M_STA)
810 		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
811 	else
812 		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
813 	return 1;
814 }
815 
816 /*
817  * Leave the specified IBSS/BSS network.  The node is assumed to
818  * be passed in with a held reference.
819  */
820 void
821 ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
822 {
823 	ic->ic_node_cleanup(ni);
824 	ieee80211_notify_node_leave(ic, ni);
825 }
826 
827 static struct ieee80211_node *
828 node_alloc(struct ieee80211_node_table *nt)
829 {
830 	struct ieee80211_node *ni;
831 
832 	MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
833 		M_80211_NODE, M_NOWAIT | M_ZERO);
834 	return ni;
835 }
836 
837 /*
838  * Reclaim any resources in a node and reset any critical
839  * state.  Typically nodes are free'd immediately after,
840  * but in some cases the storage may be reused so we need
841  * to insure consistent state (should probably fix that).
842  */
843 static void
844 node_cleanup(struct ieee80211_node *ni)
845 {
846 #define	N(a)	(sizeof(a)/sizeof(a[0]))
847 	struct ieee80211com *ic = ni->ni_ic;
848 	int i, qlen;
849 
850 	/* NB: preserve ni_table */
851 	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
852 		ic->ic_ps_sta--;
853 		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
854 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
855 		    "[%s] power save mode off, %u sta's in ps mode\n",
856 		    ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
857 	}
858 	/*
859 	 * Clear AREF flag that marks the authorization refcnt bump
860 	 * has happened.  This is probably not needed as the node
861 	 * should always be removed from the table so not found but
862 	 * do it just in case.
863 	 */
864 	ni->ni_flags &= ~IEEE80211_NODE_AREF;
865 
866 	/*
867 	 * Drain power save queue and, if needed, clear TIM.
868 	 */
869 	IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
870 	if (qlen != 0 && ic->ic_set_tim != NULL)
871 		ic->ic_set_tim(ni, 0);
872 
873 	ni->ni_associd = 0;
874 	if (ni->ni_challenge != NULL) {
875 		FREE(ni->ni_challenge, M_DEVBUF);
876 		ni->ni_challenge = NULL;
877 	}
878 	/*
879 	 * Preserve SSID, WPA, and WME ie's so the bss node is
880 	 * reusable during a re-auth/re-assoc state transition.
881 	 * If we remove these data they will not be recreated
882 	 * because they come from a probe-response or beacon frame
883 	 * which cannot be expected prior to the association-response.
884 	 * This should not be an issue when operating in other modes
885 	 * as stations leaving always go through a full state transition
886 	 * which will rebuild this state.
887 	 *
888 	 * XXX does this leave us open to inheriting old state?
889 	 */
890 	for (i = 0; i < N(ni->ni_rxfrag); i++)
891 		if (ni->ni_rxfrag[i] != NULL) {
892 			m_freem(ni->ni_rxfrag[i]);
893 			ni->ni_rxfrag[i] = NULL;
894 		}
895 	/*
896 	 * Must be careful here to remove any key map entry w/o a LOR.
897 	 */
898 	ieee80211_node_delucastkey(ni);
899 #undef N
900 }
901 
902 static void
903 node_free(struct ieee80211_node *ni)
904 {
905 	struct ieee80211com *ic = ni->ni_ic;
906 
907 	ic->ic_node_cleanup(ni);
908 	if (ni->ni_wpa_ie != NULL)
909 		FREE(ni->ni_wpa_ie, M_DEVBUF);
910 	if (ni->ni_wme_ie != NULL)
911 		FREE(ni->ni_wme_ie, M_DEVBUF);
912 	IEEE80211_NODE_SAVEQ_DESTROY(ni);
913 	FREE(ni, M_80211_NODE);
914 }
915 
916 static u_int8_t
917 node_getrssi(const struct ieee80211_node *ni)
918 {
919 	return ni->ni_rssi;
920 }
921 
922 static void
923 ieee80211_setup_node(struct ieee80211_node_table *nt,
924 	struct ieee80211_node *ni, const u_int8_t *macaddr)
925 {
926 	struct ieee80211com *ic = nt->nt_ic;
927 	int hash;
928 
929 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
930 		"%s %p<%s> in %s table\n", __func__, ni,
931 		ether_sprintf(macaddr), nt->nt_name);
932 
933 	IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
934 	hash = IEEE80211_NODE_HASH(macaddr);
935 	ieee80211_node_initref(ni);		/* mark referenced */
936 	ni->ni_chan = IEEE80211_CHAN_ANYC;
937 	ni->ni_authmode = IEEE80211_AUTH_OPEN;
938 	ni->ni_txpower = ic->ic_txpowlimit;	/* max power */
939 	ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
940 	ni->ni_inact_reload = nt->nt_inact_init;
941 	ni->ni_inact = ni->ni_inact_reload;
942 	IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
943 
944 	IEEE80211_NODE_LOCK(nt);
945 	TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
946 	LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
947 	ni->ni_table = nt;
948 	ni->ni_ic = ic;
949 	IEEE80211_NODE_UNLOCK(nt);
950 }
951 
952 struct ieee80211_node *
953 ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
954 {
955 	struct ieee80211com *ic = nt->nt_ic;
956 	struct ieee80211_node *ni;
957 
958 	ni = ic->ic_node_alloc(nt);
959 	if (ni != NULL)
960 		ieee80211_setup_node(nt, ni, macaddr);
961 	else
962 		ic->ic_stats.is_rx_nodealloc++;
963 	return ni;
964 }
965 
966 /*
967  * Craft a temporary node suitable for sending a management frame
968  * to the specified station.  We craft only as much state as we
969  * need to do the work since the node will be immediately reclaimed
970  * once the send completes.
971  */
972 struct ieee80211_node *
973 ieee80211_tmp_node(struct ieee80211com *ic, const u_int8_t *macaddr)
974 {
975 	struct ieee80211_node *ni;
976 
977 	ni = ic->ic_node_alloc(&ic->ic_sta);
978 	if (ni != NULL) {
979 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
980 			"%s %p<%s>\n", __func__, ni, ether_sprintf(macaddr));
981 
982 		IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
983 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
984 		ieee80211_node_initref(ni);		/* mark referenced */
985 		ni->ni_txpower = ic->ic_bss->ni_txpower;
986 		/* NB: required by ieee80211_fix_rate */
987 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
988 		ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey,
989 			IEEE80211_KEYIX_NONE);
990 		/* XXX optimize away */
991 		IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
992 
993 		ni->ni_table = NULL;		/* NB: pedantic */
994 		ni->ni_ic = ic;
995 	} else {
996 		/* XXX msg */
997 		ic->ic_stats.is_rx_nodealloc++;
998 	}
999 	return ni;
1000 }
1001 
1002 struct ieee80211_node *
1003 ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1004 {
1005 	struct ieee80211com *ic = nt->nt_ic;
1006 	struct ieee80211_node *ni;
1007 
1008 	ni = ic->ic_node_alloc(nt);
1009 	if (ni != NULL) {
1010 		ieee80211_setup_node(nt, ni, macaddr);
1011 		/*
1012 		 * Inherit from ic_bss.
1013 		 */
1014 		ni->ni_authmode = ic->ic_bss->ni_authmode;
1015 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1016 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1017 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
1018 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
1019 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1020 	} else
1021 		ic->ic_stats.is_rx_nodealloc++;
1022 	return ni;
1023 }
1024 
1025 static struct ieee80211_node *
1026 #ifdef IEEE80211_DEBUG_REFCNT
1027 _ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1028 	const u_int8_t *macaddr, const char *func, int line)
1029 #else
1030 _ieee80211_find_node(struct ieee80211_node_table *nt,
1031 	const u_int8_t *macaddr)
1032 #endif
1033 {
1034 	struct ieee80211_node *ni;
1035 	int hash;
1036 
1037 	IEEE80211_NODE_LOCK_ASSERT(nt);
1038 
1039 	hash = IEEE80211_NODE_HASH(macaddr);
1040 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1041 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
1042 			ieee80211_ref_node(ni);	/* mark referenced */
1043 #ifdef IEEE80211_DEBUG_REFCNT
1044 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1045 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1046 			    func, line,
1047 			    ni, ether_sprintf(ni->ni_macaddr),
1048 			    ieee80211_node_refcnt(ni));
1049 #endif
1050 			return ni;
1051 		}
1052 	}
1053 	return NULL;
1054 }
1055 #ifdef IEEE80211_DEBUG_REFCNT
1056 #define	_ieee80211_find_node(nt, mac) \
1057 	_ieee80211_find_node_debug(nt, mac, func, line)
1058 #endif
1059 
1060 struct ieee80211_node *
1061 #ifdef IEEE80211_DEBUG_REFCNT
1062 ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1063 	const u_int8_t *macaddr, const char *func, int line)
1064 #else
1065 ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1066 #endif
1067 {
1068 	struct ieee80211_node *ni;
1069 
1070 	IEEE80211_NODE_LOCK(nt);
1071 	ni = _ieee80211_find_node(nt, macaddr);
1072 	IEEE80211_NODE_UNLOCK(nt);
1073 	return ni;
1074 }
1075 
1076 /*
1077  * Fake up a node; this handles node discovery in adhoc mode.
1078  * Note that for the driver's benefit we we treat this like
1079  * an association so the driver has an opportunity to setup
1080  * it's private state.
1081  */
1082 struct ieee80211_node *
1083 ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
1084 	const u_int8_t macaddr[IEEE80211_ADDR_LEN])
1085 {
1086 	struct ieee80211com *ic = nt->nt_ic;
1087 	struct ieee80211_node *ni;
1088 
1089 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1090 	    "%s: mac<%s>\n", __func__, ether_sprintf(macaddr));
1091 	ni = ieee80211_dup_bss(nt, macaddr);
1092 	if (ni != NULL) {
1093 		/* XXX no rate negotiation; just dup */
1094 		ni->ni_rates = ic->ic_bss->ni_rates;
1095 		if (ic->ic_newassoc != NULL)
1096 			ic->ic_newassoc(ni, 1);
1097 		/* XXX not right for 802.1x/WPA */
1098 		ieee80211_node_authorize(ni);
1099 		if (ic->ic_opmode == IEEE80211_M_AHDEMO) {
1100 			/*
1101 			 * Blindly propagate capabilities based on the
1102 			 * local configuration.  In particular this permits
1103 			 * us to use QoS to disable ACK's.
1104 			 */
1105 			if (ic->ic_flags & IEEE80211_F_WME)
1106 				ni->ni_flags |= IEEE80211_NODE_QOS;
1107 		}
1108 	}
1109 	return ni;
1110 }
1111 
1112 #ifdef IEEE80211_DEBUG
1113 static void
1114 dump_probe_beacon(u_int8_t subtype, int isnew,
1115 	const u_int8_t mac[IEEE80211_ADDR_LEN],
1116 	const struct ieee80211_scanparams *sp)
1117 {
1118 
1119 	printf("[%s] %s%s on chan %u (bss chan %u) ",
1120 	    ether_sprintf(mac), isnew ? "new " : "",
1121 	    ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
1122 	    sp->chan, sp->bchan);
1123 	ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
1124 	printf("\n");
1125 
1126 	if (isnew) {
1127 		printf("[%s] caps 0x%x bintval %u erp 0x%x",
1128 			ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
1129 		if (sp->country != NULL) {
1130 #ifdef __FreeBSD__
1131 			printf(" country info %*D",
1132 				sp->country[1], sp->country+2, " ");
1133 #else
1134 			int i;
1135 			printf(" country info");
1136 			for (i = 0; i < sp->country[1]; i++)
1137 				printf(" %02x", sp->country[i+2]);
1138 #endif
1139 		}
1140 		printf("\n");
1141 	}
1142 }
1143 #endif /* IEEE80211_DEBUG */
1144 
1145 static void
1146 saveie(u_int8_t **iep, const u_int8_t *ie)
1147 {
1148 
1149 	if (ie == NULL)
1150 		*iep = NULL;
1151 	else
1152 		ieee80211_saveie(iep, ie);
1153 }
1154 
1155 /*
1156  * Process a beacon or probe response frame.
1157  */
1158 void
1159 ieee80211_add_scan(struct ieee80211com *ic,
1160 	const struct ieee80211_scanparams *sp,
1161 	const struct ieee80211_frame *wh,
1162 	int subtype, int rssi, int rstamp)
1163 {
1164 #define	ISPROBE(_st)	((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
1165 	struct ieee80211_node_table *nt = &ic->ic_scan;
1166 	struct ieee80211_node *ni;
1167 	int newnode = 0;
1168 
1169 	ni = ieee80211_find_node(nt, wh->i_addr2);
1170 	if (ni == NULL) {
1171 		/*
1172 		 * Create a new entry.
1173 		 */
1174 		ni = ic->ic_node_alloc(nt);
1175 		if (ni == NULL) {
1176 			ic->ic_stats.is_rx_nodealloc++;
1177 			return;
1178 		}
1179 		ieee80211_setup_node(nt, ni, wh->i_addr2);
1180 		/*
1181 		 * XXX inherit from ic_bss.
1182 		 */
1183 		ni->ni_authmode = ic->ic_bss->ni_authmode;
1184 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1185 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1186 		ieee80211_set_chan(ic, ni, ic->ic_curchan);
1187 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1188 		newnode = 1;
1189 	}
1190 #ifdef IEEE80211_DEBUG
1191 	if (ieee80211_msg_scan(ic) && (ic->ic_flags & IEEE80211_F_SCAN))
1192 		dump_probe_beacon(subtype, newnode, wh->i_addr2, sp);
1193 #endif
1194 	/* XXX ap beaconing multiple ssid w/ same bssid */
1195 	if (sp->ssid[1] != 0 &&
1196 	    (ISPROBE(subtype) || ni->ni_esslen == 0)) {
1197 		ni->ni_esslen = sp->ssid[1];
1198 		memset(ni->ni_essid, 0, sizeof(ni->ni_essid));
1199 		memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
1200 	}
1201 	ni->ni_scangen = ic->ic_scan.nt_scangen;
1202 	IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
1203 	ni->ni_rssi = rssi;
1204 	ni->ni_rstamp = rstamp;
1205 	memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
1206 	ni->ni_intval = sp->bintval;
1207 	ni->ni_capinfo = sp->capinfo;
1208 	ni->ni_chan = &ic->ic_channels[sp->chan];
1209 	ni->ni_fhdwell = sp->fhdwell;
1210 	ni->ni_fhindex = sp->fhindex;
1211 	ni->ni_erp = sp->erp;
1212 	if (sp->tim != NULL) {
1213 		struct ieee80211_tim_ie *ie =
1214 		    (struct ieee80211_tim_ie *) sp->tim;
1215 
1216 		ni->ni_dtim_count = ie->tim_count;
1217 		ni->ni_dtim_period = ie->tim_period;
1218 	}
1219 	/*
1220 	 * Record the byte offset from the mac header to
1221 	 * the start of the TIM information element for
1222 	 * use by hardware and/or to speedup software
1223 	 * processing of beacon frames.
1224 	 */
1225 	ni->ni_timoff = sp->timoff;
1226 	/*
1227 	 * Record optional information elements that might be
1228 	 * used by applications or drivers.
1229 	 */
1230 	saveie(&ni->ni_wme_ie, sp->wme);
1231 	saveie(&ni->ni_wpa_ie, sp->wpa);
1232 
1233 	/* NB: must be after ni_chan is setup */
1234 	ieee80211_setup_rates(ni, sp->rates, sp->xrates, IEEE80211_F_DOSORT);
1235 
1236 	if (!newnode)
1237 		ieee80211_free_node(ni);
1238 #undef ISPROBE
1239 }
1240 
1241 void
1242 ieee80211_init_neighbor(struct ieee80211_node *ni,
1243 	const struct ieee80211_frame *wh,
1244 	const struct ieee80211_scanparams *sp)
1245 {
1246 
1247 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1248 	    "%s: %p<%s>\n", __func__, ni, ether_sprintf(ni->ni_macaddr));
1249 	ni->ni_esslen = sp->ssid[1];
1250 	memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
1251 	IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
1252 	memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
1253 	ni->ni_intval = sp->bintval;
1254 	ni->ni_capinfo = sp->capinfo;
1255 	ni->ni_chan = ni->ni_ic->ic_curchan;
1256 	ni->ni_fhdwell = sp->fhdwell;
1257 	ni->ni_fhindex = sp->fhindex;
1258 	ni->ni_erp = sp->erp;
1259 	ni->ni_timoff = sp->timoff;
1260 	if (sp->wme != NULL)
1261 		ieee80211_saveie(&ni->ni_wme_ie, sp->wme);
1262 	if (sp->wpa != NULL)
1263 		ieee80211_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 
1269 /*
1270  * Do node discovery in adhoc mode on receipt of a beacon
1271  * or probe response frame.  Note that for the driver's
1272  * benefit we we treat this like an association so the
1273  * driver has an opportunity to setup it's private state.
1274  */
1275 struct ieee80211_node *
1276 ieee80211_add_neighbor(struct ieee80211com *ic,
1277 	const struct ieee80211_frame *wh,
1278 	const struct ieee80211_scanparams *sp)
1279 {
1280 	struct ieee80211_node *ni;
1281 
1282 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1283 	    "%s: mac<%s>\n", __func__, ether_sprintf(wh->i_addr2));
1284 	ni = ieee80211_dup_bss(&ic->ic_sta, wh->i_addr2);/* XXX alloc_node? */
1285 	if (ni != NULL) {
1286 		ieee80211_init_neighbor(ni, wh, sp);
1287 		if (ic->ic_newassoc != NULL)
1288 			ic->ic_newassoc(ni, 1);
1289 		/* XXX not right for 802.1x/WPA */
1290 		ieee80211_node_authorize(ni);
1291 	}
1292 	return ni;
1293 }
1294 
1295 #define	IS_CTL(wh) \
1296 	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1297 #define	IS_PSPOLL(wh) \
1298 	((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
1299 /*
1300  * Locate the node for sender, track state, and then pass the
1301  * (referenced) node up to the 802.11 layer for its use.  We
1302  * are required to pass some node so we fall back to ic_bss
1303  * when this frame is from an unknown sender.  The 802.11 layer
1304  * knows this means the sender wasn't in the node table and
1305  * acts accordingly.
1306  */
1307 struct ieee80211_node *
1308 #ifdef IEEE80211_DEBUG_REFCNT
1309 ieee80211_find_rxnode_debug(struct ieee80211com *ic,
1310 	const struct ieee80211_frame_min *wh, const char *func, int line)
1311 #else
1312 ieee80211_find_rxnode(struct ieee80211com *ic,
1313 	const struct ieee80211_frame_min *wh)
1314 #endif
1315 {
1316 	struct ieee80211_node_table *nt;
1317 	struct ieee80211_node *ni;
1318 
1319 	/* XXX may want scanned nodes in the neighbor table for adhoc */
1320 	if (ic->ic_opmode == IEEE80211_M_STA ||
1321 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1322 	    (ic->ic_flags & IEEE80211_F_SCAN))
1323 		nt = &ic->ic_scan;
1324 	else
1325 		nt = &ic->ic_sta;
1326 	/* XXX check ic_bss first in station mode */
1327 	/* XXX 4-address frames? */
1328 	IEEE80211_NODE_LOCK(nt);
1329 	if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1330 		ni = _ieee80211_find_node(nt, wh->i_addr1);
1331 	else
1332 		ni = _ieee80211_find_node(nt, wh->i_addr2);
1333 	if (ni == NULL)
1334 		ni = ieee80211_ref_node(ic->ic_bss);
1335 	IEEE80211_NODE_UNLOCK(nt);
1336 
1337 	return ni;
1338 }
1339 
1340 /*
1341  * Like ieee80211_find_rxnode but use the supplied h/w
1342  * key index as a hint to locate the node in the key
1343  * mapping table.  If an entry is present at the key
1344  * index we return it; otherwise do a normal lookup and
1345  * update the mapping table if the station has a unicast
1346  * key assigned to it.
1347  */
1348 struct ieee80211_node *
1349 #ifdef IEEE80211_DEBUG_REFCNT
1350 ieee80211_find_rxnode_withkey_debug(struct ieee80211com *ic,
1351 	const struct ieee80211_frame_min *wh, ieee80211_keyix keyix,
1352 	const char *func, int line)
1353 #else
1354 ieee80211_find_rxnode_withkey(struct ieee80211com *ic,
1355 	const struct ieee80211_frame_min *wh, ieee80211_keyix keyix)
1356 #endif
1357 {
1358 	struct ieee80211_node_table *nt;
1359 	struct ieee80211_node *ni;
1360 
1361 	if (ic->ic_opmode == IEEE80211_M_STA ||
1362 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1363 	    (ic->ic_flags & IEEE80211_F_SCAN))
1364 		nt = &ic->ic_scan;
1365 	else
1366 		nt = &ic->ic_sta;
1367 	IEEE80211_NODE_LOCK(nt);
1368 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax)
1369 		ni = nt->nt_keyixmap[keyix];
1370 	else
1371 		ni = NULL;
1372 	if (ni == NULL) {
1373 		if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1374 			ni = _ieee80211_find_node(nt, wh->i_addr1);
1375 		else
1376 			ni = _ieee80211_find_node(nt, wh->i_addr2);
1377 		if (ni == NULL)
1378 			ni = ieee80211_ref_node(ic->ic_bss);
1379 		if (nt->nt_keyixmap != NULL) {
1380 			/*
1381 			 * If the station has a unicast key cache slot
1382 			 * assigned update the key->node mapping table.
1383 			 */
1384 			keyix = ni->ni_ucastkey.wk_rxkeyix;
1385 			/* XXX can keyixmap[keyix] != NULL? */
1386 			if (keyix < nt->nt_keyixmax &&
1387 			    nt->nt_keyixmap[keyix] == NULL) {
1388 				IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1389 				    "%s: add key map entry %p<%s> refcnt %d\n",
1390 				    __func__, ni, ether_sprintf(ni->ni_macaddr),
1391 				    ieee80211_node_refcnt(ni)+1);
1392 				nt->nt_keyixmap[keyix] = ieee80211_ref_node(ni);
1393 			}
1394 		}
1395 	} else {
1396 		ieee80211_ref_node(ni);
1397 	}
1398 	IEEE80211_NODE_UNLOCK(nt);
1399 
1400 	return ni;
1401 }
1402 #undef IS_PSPOLL
1403 #undef IS_CTL
1404 
1405 /*
1406  * Return a reference to the appropriate node for sending
1407  * a data frame.  This handles node discovery in adhoc networks.
1408  */
1409 struct ieee80211_node *
1410 #ifdef IEEE80211_DEBUG_REFCNT
1411 ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
1412 	const char *func, int line)
1413 #else
1414 ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
1415 #endif
1416 {
1417 	struct ieee80211_node_table *nt = &ic->ic_sta;
1418 	struct ieee80211_node *ni;
1419 
1420 	/*
1421 	 * The destination address should be in the node table
1422 	 * unless this is a multicast/broadcast frame.  We can
1423 	 * also optimize station mode operation, all frames go
1424 	 * to the bss node.
1425 	 */
1426 	/* XXX can't hold lock across dup_bss 'cuz of recursive locking */
1427 	IEEE80211_NODE_LOCK(nt);
1428 	if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
1429 		ni = ieee80211_ref_node(ic->ic_bss);
1430 	else
1431 		ni = _ieee80211_find_node(nt, macaddr);
1432 	IEEE80211_NODE_UNLOCK(nt);
1433 
1434 	if (ni == NULL) {
1435 		if (ic->ic_opmode == IEEE80211_M_IBSS ||
1436 		    ic->ic_opmode == IEEE80211_M_AHDEMO) {
1437 			/*
1438 			 * In adhoc mode cons up a node for the destination.
1439 			 * Note that we need an additional reference for the
1440 			 * caller to be consistent with _ieee80211_find_node.
1441 			 */
1442 			ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
1443 			if (ni != NULL)
1444 				(void) ieee80211_ref_node(ni);
1445 		} else {
1446 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
1447 				"[%s] no node, discard frame (%s)\n",
1448 				ether_sprintf(macaddr), __func__);
1449 			ic->ic_stats.is_tx_nonode++;
1450 		}
1451 	}
1452 	return ni;
1453 }
1454 
1455 /*
1456  * Like find but search based on the channel too.
1457  */
1458 struct ieee80211_node *
1459 #ifdef IEEE80211_DEBUG_REFCNT
1460 ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
1461 	const u_int8_t *macaddr, struct ieee80211_channel *chan,
1462 	const char *func, int line)
1463 #else
1464 ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
1465 	const u_int8_t *macaddr, struct ieee80211_channel *chan)
1466 #endif
1467 {
1468 	struct ieee80211_node *ni;
1469 	int hash;
1470 
1471 	hash = IEEE80211_NODE_HASH(macaddr);
1472 	IEEE80211_NODE_LOCK(nt);
1473 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1474 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1475 		    ni->ni_chan == chan) {
1476 			ieee80211_ref_node(ni);		/* mark referenced */
1477 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1478 #ifdef IEEE80211_DEBUG_REFCNT
1479 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1480 			    func, line,
1481 #else
1482 			    "%s %p<%s> refcnt %d\n", __func__,
1483 #endif
1484 			    ni, ether_sprintf(ni->ni_macaddr),
1485 			    ieee80211_node_refcnt(ni));
1486 			break;
1487 		}
1488 	}
1489 	IEEE80211_NODE_UNLOCK(nt);
1490 	return ni;
1491 }
1492 
1493 /*
1494  * Like find but search based on the ssid too.
1495  */
1496 struct ieee80211_node *
1497 #ifdef IEEE80211_DEBUG_REFCNT
1498 ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
1499 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
1500 	const char *func, int line)
1501 #else
1502 ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
1503 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
1504 #endif
1505 {
1506 #define	MATCH_SSID(ni, ssid, ssidlen) \
1507 	(ni->ni_esslen == ssidlen && memcmp(ni->ni_essid, ssid, ssidlen) == 0)
1508 	static const u_int8_t zeromac[IEEE80211_ADDR_LEN];
1509 	struct ieee80211com *ic = nt->nt_ic;
1510 	struct ieee80211_node *ni;
1511 	int hash;
1512 
1513 	IEEE80211_NODE_LOCK(nt);
1514 	/*
1515 	 * A mac address that is all zero means match only the ssid;
1516 	 * otherwise we must match both.
1517 	 */
1518 	if (IEEE80211_ADDR_EQ(macaddr, zeromac)) {
1519 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1520 			if (MATCH_SSID(ni, ssid, ssidlen))
1521 				break;
1522 		}
1523 	} else {
1524 		hash = IEEE80211_NODE_HASH(macaddr);
1525 		LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1526 			if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1527 			    MATCH_SSID(ni, ssid, ssidlen))
1528 				break;
1529 		}
1530 	}
1531 	if (ni != NULL) {
1532 		ieee80211_ref_node(ni);	/* mark referenced */
1533 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1534 #ifdef IEEE80211_DEBUG_REFCNT
1535 		    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1536 		    func, line,
1537 #else
1538 		    "%s %p<%s> refcnt %d\n", __func__,
1539 #endif
1540 		     ni, ether_sprintf(ni->ni_macaddr),
1541 		     ieee80211_node_refcnt(ni));
1542 	}
1543 	IEEE80211_NODE_UNLOCK(nt);
1544 	return ni;
1545 #undef MATCH_SSID
1546 }
1547 
1548 static void
1549 _ieee80211_free_node(struct ieee80211_node *ni)
1550 {
1551 	struct ieee80211com *ic = ni->ni_ic;
1552 	struct ieee80211_node_table *nt = ni->ni_table;
1553 
1554 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1555 		"%s %p<%s> in %s table\n", __func__, ni,
1556 		ether_sprintf(ni->ni_macaddr),
1557 		nt != NULL ? nt->nt_name : "<gone>");
1558 
1559 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1560 	if (nt != NULL) {
1561 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1562 		LIST_REMOVE(ni, ni_hash);
1563 	}
1564 	ic->ic_node_free(ni);
1565 }
1566 
1567 void
1568 #ifdef IEEE80211_DEBUG_REFCNT
1569 ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
1570 #else
1571 ieee80211_free_node(struct ieee80211_node *ni)
1572 #endif
1573 {
1574 	struct ieee80211_node_table *nt = ni->ni_table;
1575 
1576 #ifdef IEEE80211_DEBUG_REFCNT
1577 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1578 		"%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line, ni,
1579 		 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
1580 #endif
1581 	if (nt != NULL) {
1582 		IEEE80211_NODE_LOCK(nt);
1583 		if (ieee80211_node_dectestref(ni)) {
1584 			/*
1585 			 * Last reference, reclaim state.
1586 			 */
1587 			_ieee80211_free_node(ni);
1588 		} else if (ieee80211_node_refcnt(ni) == 1 &&
1589 		    nt->nt_keyixmap != NULL) {
1590 			ieee80211_keyix keyix;
1591 			/*
1592 			 * Check for a last reference in the key mapping table.
1593 			 */
1594 			keyix = ni->ni_ucastkey.wk_rxkeyix;
1595 			if (keyix < nt->nt_keyixmax &&
1596 			    nt->nt_keyixmap[keyix] == ni) {
1597 				IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1598 				    "%s: %p<%s> clear key map entry", __func__,
1599 				    ni, ether_sprintf(ni->ni_macaddr));
1600 				nt->nt_keyixmap[keyix] = NULL;
1601 				ieee80211_node_decref(ni); /* XXX needed? */
1602 				_ieee80211_free_node(ni);
1603 			}
1604 		}
1605 		IEEE80211_NODE_UNLOCK(nt);
1606 	} else {
1607 		if (ieee80211_node_dectestref(ni))
1608 			_ieee80211_free_node(ni);
1609 	}
1610 }
1611 
1612 /*
1613  * Reclaim a unicast key and clear any key cache state.
1614  */
1615 int
1616 ieee80211_node_delucastkey(struct ieee80211_node *ni)
1617 {
1618 	struct ieee80211com *ic = ni->ni_ic;
1619 	struct ieee80211_node_table *nt = &ic->ic_sta;
1620 	struct ieee80211_node *nikey;
1621 	ieee80211_keyix keyix;
1622 	int isowned, status;
1623 
1624 	/*
1625 	 * NB: We must beware of LOR here; deleting the key
1626 	 * can cause the crypto layer to block traffic updates
1627 	 * which can generate a LOR against the node table lock;
1628 	 * grab it here and stash the key index for our use below.
1629 	 *
1630 	 * Must also beware of recursion on the node table lock.
1631 	 * When called from node_cleanup we may already have
1632 	 * the node table lock held.  Unfortunately there's no
1633 	 * way to separate out this path so we must do this
1634 	 * conditionally.
1635 	 */
1636 	isowned = IEEE80211_NODE_IS_LOCKED(nt);
1637 	if (!isowned)
1638 		IEEE80211_NODE_LOCK(nt);
1639 	keyix = ni->ni_ucastkey.wk_rxkeyix;
1640 	status = ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
1641 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax) {
1642 		nikey = nt->nt_keyixmap[keyix];
1643 		nt->nt_keyixmap[keyix] = NULL;;
1644 	} else
1645 		nikey = NULL;
1646 	if (!isowned)
1647 		IEEE80211_NODE_UNLOCK(&ic->ic_sta);
1648 
1649 	if (nikey != NULL) {
1650 		KASSERT(nikey == ni,
1651 			("key map out of sync, ni %p nikey %p", ni, nikey));
1652 		IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1653 			"%s: delete key map entry %p<%s> refcnt %d\n",
1654 			__func__, ni, ether_sprintf(ni->ni_macaddr),
1655 			ieee80211_node_refcnt(ni)-1);
1656 		ieee80211_free_node(ni);
1657 	}
1658 	return status;
1659 }
1660 
1661 /*
1662  * Reclaim a node.  If this is the last reference count then
1663  * do the normal free work.  Otherwise remove it from the node
1664  * table and mark it gone by clearing the back-reference.
1665  */
1666 static void
1667 node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1668 {
1669 	ieee80211_keyix keyix;
1670 
1671 	IEEE80211_NODE_LOCK_ASSERT(nt);
1672 
1673 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1674 		"%s: remove %p<%s> from %s table, refcnt %d\n",
1675 		__func__, ni, ether_sprintf(ni->ni_macaddr),
1676 		nt->nt_name, ieee80211_node_refcnt(ni)-1);
1677 	/*
1678 	 * Clear any entry in the unicast key mapping table.
1679 	 * We need to do it here so rx lookups don't find it
1680 	 * in the mapping table even if it's not in the hash
1681 	 * table.  We cannot depend on the mapping table entry
1682 	 * being cleared because the node may not be free'd.
1683 	 */
1684 	keyix = ni->ni_ucastkey.wk_rxkeyix;
1685 	if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax &&
1686 	    nt->nt_keyixmap[keyix] == ni) {
1687 		IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1688 			"%s: %p<%s> clear key map entry\n",
1689 			__func__, ni, ether_sprintf(ni->ni_macaddr));
1690 		nt->nt_keyixmap[keyix] = NULL;
1691 		ieee80211_node_decref(ni);	/* NB: don't need free */
1692 	}
1693 	if (!ieee80211_node_dectestref(ni)) {
1694 		/*
1695 		 * Other references are present, just remove the
1696 		 * node from the table so it cannot be found.  When
1697 		 * the references are dropped storage will be
1698 		 * reclaimed.
1699 		 */
1700 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1701 		LIST_REMOVE(ni, ni_hash);
1702 		ni->ni_table = NULL;		/* clear reference */
1703 	} else
1704 		_ieee80211_free_node(ni);
1705 }
1706 
1707 static void
1708 ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
1709 {
1710 	struct ieee80211com *ic = nt->nt_ic;
1711 	struct ieee80211_node *ni;
1712 
1713 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1714 		"%s: free all nodes in %s table\n", __func__, nt->nt_name);
1715 
1716 	while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
1717 		if (ni->ni_associd != 0) {
1718 			if (ic->ic_auth->ia_node_leave != NULL)
1719 				ic->ic_auth->ia_node_leave(ic, ni);
1720 			IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1721 		}
1722 		node_reclaim(nt, ni);
1723 	}
1724 	ieee80211_reset_erp(ic);
1725 }
1726 
1727 static void
1728 ieee80211_free_allnodes(struct ieee80211_node_table *nt)
1729 {
1730 
1731 	IEEE80211_NODE_LOCK(nt);
1732 	ieee80211_free_allnodes_locked(nt);
1733 	IEEE80211_NODE_UNLOCK(nt);
1734 }
1735 
1736 /*
1737  * Timeout entries in the scan cache.
1738  */
1739 static void
1740 ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
1741 {
1742 	struct ieee80211com *ic = nt->nt_ic;
1743 	struct ieee80211_node *ni, *tni;
1744 
1745 	IEEE80211_NODE_LOCK(nt);
1746 	ni = ic->ic_bss;
1747 	/* XXX belongs elsewhere */
1748 	if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
1749 		m_freem(ni->ni_rxfrag[0]);
1750 		ni->ni_rxfrag[0] = NULL;
1751 	}
1752 	TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
1753 		if (ni->ni_inact && --ni->ni_inact == 0) {
1754 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1755 			    "[%s] scan candidate purged from cache "
1756 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1757 			    ieee80211_node_refcnt(ni));
1758 			node_reclaim(nt, ni);
1759 		}
1760 	}
1761 	IEEE80211_NODE_UNLOCK(nt);
1762 
1763 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1764 }
1765 
1766 /*
1767  * Timeout inactive stations and do related housekeeping.
1768  * Note that we cannot hold the node lock while sending a
1769  * frame as this would lead to a LOR.  Instead we use a
1770  * generation number to mark nodes that we've scanned and
1771  * drop the lock and restart a scan if we have to time out
1772  * a node.  Since we are single-threaded by virtue of
1773  * controlling the inactivity timer we can be sure this will
1774  * process each node only once.
1775  */
1776 static void
1777 ieee80211_timeout_stations(struct ieee80211_node_table *nt)
1778 {
1779 	struct ieee80211com *ic = nt->nt_ic;
1780 	struct ieee80211_node *ni;
1781 	u_int gen;
1782 	int isadhoc;
1783 
1784 	isadhoc = (ic->ic_opmode == IEEE80211_M_IBSS ||
1785 		   ic->ic_opmode == IEEE80211_M_AHDEMO);
1786 	IEEE80211_SCAN_LOCK(nt);
1787 	gen = nt->nt_scangen++;
1788 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1789 		"%s: %s scangen %u\n", __func__, nt->nt_name, gen);
1790 restart:
1791 	IEEE80211_NODE_LOCK(nt);
1792 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1793 		if (ni->ni_scangen == gen)	/* previously handled */
1794 			continue;
1795 		ni->ni_scangen = gen;
1796 		/*
1797 		 * Ignore entries for which have yet to receive an
1798 		 * authentication frame.  These are transient and
1799 		 * will be reclaimed when the last reference to them
1800 		 * goes away (when frame xmits complete).
1801 		 */
1802 		if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
1803 		    (ni->ni_flags & IEEE80211_NODE_AREF) == 0)
1804 			continue;
1805 		/*
1806 		 * Free fragment if not needed anymore
1807 		 * (last fragment older than 1s).
1808 		 * XXX doesn't belong here
1809 		 */
1810 		if (ni->ni_rxfrag[0] != NULL &&
1811 		    ticks > ni->ni_rxfragstamp + hz) {
1812 			m_freem(ni->ni_rxfrag[0]);
1813 			ni->ni_rxfrag[0] = NULL;
1814 		}
1815 		/*
1816 		 * Special case ourself; we may be idle for extended periods
1817 		 * of time and regardless reclaiming our state is wrong.
1818 		 */
1819 		if (ni == ic->ic_bss)
1820 			continue;
1821 		ni->ni_inact--;
1822 		if (ni->ni_associd != 0 || isadhoc) {
1823 			/*
1824 			 * Age frames on the power save queue. The
1825 			 * aging interval is 4 times the listen
1826 			 * interval specified by the station.  This
1827 			 * number is factored into the age calculations
1828 			 * when the frame is placed on the queue.  We
1829 			 * store ages as time differences we can check
1830 			 * and/or adjust only the head of the list.
1831 			 */
1832 			if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
1833 				struct mbuf *m;
1834 				int discard = 0;
1835 
1836 				IEEE80211_NODE_SAVEQ_LOCK(ni);
1837 				while (IF_POLL(&ni->ni_savedq, m) != NULL &&
1838 				     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
1839 IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
1840 					_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
1841 					m_freem(m);
1842 					discard++;
1843 				}
1844 				if (m != NULL)
1845 					M_AGE_SUB(m, IEEE80211_INACT_WAIT);
1846 				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1847 
1848 				if (discard != 0) {
1849 					IEEE80211_DPRINTF(ic,
1850 					    IEEE80211_MSG_POWER,
1851 					    "[%s] discard %u frames for age\n",
1852 					    ether_sprintf(ni->ni_macaddr),
1853 					    discard);
1854 					IEEE80211_NODE_STAT_ADD(ni,
1855 						ps_discard, discard);
1856 					if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
1857 						ic->ic_set_tim(ni, 0);
1858 				}
1859 			}
1860 			/*
1861 			 * Probe the station before time it out.  We
1862 			 * send a null data frame which may not be
1863 			 * universally supported by drivers (need it
1864 			 * for ps-poll support so it should be...).
1865 			 */
1866 			if (0 < ni->ni_inact &&
1867 			    ni->ni_inact <= ic->ic_inact_probe) {
1868 				IEEE80211_NOTE(ic,
1869 				    IEEE80211_MSG_INACT | IEEE80211_MSG_NODE,
1870 				    ni, "%s",
1871 				    "probe station due to inactivity");
1872 				/*
1873 				 * Grab a reference before unlocking the table
1874 				 * so the node cannot be reclaimed before we
1875 				 * send the frame. ieee80211_send_nulldata
1876 				 * understands we've done this and reclaims the
1877 				 * ref for us as needed.
1878 				 */
1879 				ieee80211_ref_node(ni);
1880 				IEEE80211_NODE_UNLOCK(nt);
1881 				ieee80211_send_nulldata(ni);
1882 				/* XXX stat? */
1883 				goto restart;
1884 			}
1885 		}
1886 		if (ni->ni_inact <= 0) {
1887 			IEEE80211_NOTE(ic,
1888 			    IEEE80211_MSG_INACT | IEEE80211_MSG_NODE, ni,
1889 			    "station timed out due to inactivity "
1890 			    "(refcnt %u)", ieee80211_node_refcnt(ni));
1891 			/*
1892 			 * Send a deauthenticate frame and drop the station.
1893 			 * This is somewhat complicated due to reference counts
1894 			 * and locking.  At this point a station will typically
1895 			 * have a reference count of 1.  ieee80211_node_leave
1896 			 * will do a "free" of the node which will drop the
1897 			 * reference count.  But in the meantime a reference
1898 			 * wil be held by the deauth frame.  The actual reclaim
1899 			 * of the node will happen either after the tx is
1900 			 * completed or by ieee80211_node_leave.
1901 			 *
1902 			 * Separately we must drop the node lock before sending
1903 			 * in case the driver takes a lock, as this will result
1904 			 * in  LOR between the node lock and the driver lock.
1905 			 */
1906 			IEEE80211_NODE_UNLOCK(nt);
1907 			if (ni->ni_associd != 0) {
1908 				IEEE80211_SEND_MGMT(ic, ni,
1909 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
1910 				    IEEE80211_REASON_AUTH_EXPIRE);
1911 			}
1912 			ieee80211_node_leave(ic, ni);
1913 			ic->ic_stats.is_node_timeout++;
1914 			goto restart;
1915 		}
1916 	}
1917 	IEEE80211_NODE_UNLOCK(nt);
1918 
1919 	IEEE80211_SCAN_UNLOCK(nt);
1920 
1921 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1922 }
1923 
1924 void
1925 ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
1926 {
1927 	struct ieee80211_node *ni;
1928 	u_int gen;
1929 
1930 	IEEE80211_SCAN_LOCK(nt);
1931 	gen = nt->nt_scangen++;
1932 restart:
1933 	IEEE80211_NODE_LOCK(nt);
1934 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1935 		if (ni->ni_scangen != gen) {
1936 			ni->ni_scangen = gen;
1937 			(void) ieee80211_ref_node(ni);
1938 			IEEE80211_NODE_UNLOCK(nt);
1939 			(*f)(arg, ni);
1940 			ieee80211_free_node(ni);
1941 			goto restart;
1942 		}
1943 	}
1944 	IEEE80211_NODE_UNLOCK(nt);
1945 
1946 	IEEE80211_SCAN_UNLOCK(nt);
1947 }
1948 
1949 void
1950 ieee80211_dump_node(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1951 {
1952 	printf("0x%p: mac %s refcnt %d\n", ni,
1953 		ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
1954 	printf("\tscangen %u authmode %u flags 0x%x\n",
1955 		ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
1956 	printf("\tassocid 0x%x txpower %u vlan %u\n",
1957 		ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
1958 	printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
1959 		ni->ni_txseqs[0],
1960 		ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
1961 		ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
1962 		ni->ni_rxfragstamp);
1963 	printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
1964 		ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
1965 	printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
1966 		ether_sprintf(ni->ni_bssid),
1967 		ni->ni_esslen, ni->ni_essid,
1968 		ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
1969 	printf("\tfails %u inact %u txrate %u\n",
1970 		ni->ni_fails, ni->ni_inact, ni->ni_txrate);
1971 }
1972 
1973 void
1974 ieee80211_dump_nodes(struct ieee80211_node_table *nt)
1975 {
1976 	ieee80211_iterate_nodes(nt,
1977 		(ieee80211_iter_func *) ieee80211_dump_node, nt);
1978 }
1979 
1980 /*
1981  * Handle a station joining an 11g network.
1982  */
1983 static void
1984 ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1985 {
1986 
1987 	/*
1988 	 * Station isn't capable of short slot time.  Bump
1989 	 * the count of long slot time stations and disable
1990 	 * use of short slot time.  Note that the actual switch
1991 	 * over to long slot time use may not occur until the
1992 	 * next beacon transmission (per sec. 7.3.1.4 of 11g).
1993 	 */
1994 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1995 		ic->ic_longslotsta++;
1996 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1997 		    "[%s] station needs long slot time, count %d\n",
1998 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1999 		/* XXX vap's w/ conflicting needs won't work */
2000 		ieee80211_set_shortslottime(ic, 0);
2001 	}
2002 	/*
2003 	 * If the new station is not an ERP station
2004 	 * then bump the counter and enable protection
2005 	 * if configured.
2006 	 */
2007 	if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
2008 		ic->ic_nonerpsta++;
2009 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2010 		    "[%s] station is !ERP, %d non-ERP stations associated\n",
2011 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
2012 		/*
2013 		 * If protection is configured, enable it.
2014 		 */
2015 		if (ic->ic_protmode != IEEE80211_PROT_NONE) {
2016 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2017 			    "%s: enable use of protection\n", __func__);
2018 			ic->ic_flags |= IEEE80211_F_USEPROT;
2019 		}
2020 		/*
2021 		 * If station does not support short preamble
2022 		 * then we must enable use of Barker preamble.
2023 		 */
2024 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
2025 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2026 			    "[%s] station needs long preamble\n",
2027 			    ether_sprintf(ni->ni_macaddr));
2028 			ic->ic_flags |= IEEE80211_F_USEBARKER;
2029 			ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
2030 		}
2031 	} else
2032 		ni->ni_flags |= IEEE80211_NODE_ERP;
2033 }
2034 
2035 void
2036 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
2037 {
2038 	int newassoc;
2039 
2040 	if (ni->ni_associd == 0) {
2041 		u_int16_t aid;
2042 
2043 		/*
2044 		 * It would be good to search the bitmap
2045 		 * more efficiently, but this will do for now.
2046 		 */
2047 		for (aid = 1; aid < ic->ic_max_aid; aid++) {
2048 			if (!IEEE80211_AID_ISSET(aid,
2049 			    ic->ic_aid_bitmap))
2050 				break;
2051 		}
2052 		if (aid >= ic->ic_max_aid) {
2053 			IEEE80211_SEND_MGMT(ic, ni, resp,
2054 			    IEEE80211_REASON_ASSOC_TOOMANY);
2055 			ieee80211_node_leave(ic, ni);
2056 			return;
2057 		}
2058 		ni->ni_associd = aid | 0xc000;
2059 		IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
2060 		ic->ic_sta_assoc++;
2061 		newassoc = 1;
2062 		if (ic->ic_curmode == IEEE80211_MODE_11G)
2063 			ieee80211_node_join_11g(ic, ni);
2064 	} else
2065 		newassoc = 0;
2066 
2067 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
2068 	    "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
2069 	    ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
2070 	    IEEE80211_NODE_AID(ni),
2071 	    ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
2072 	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
2073 	    ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
2074 	    ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
2075 	);
2076 
2077 	/* give driver a chance to setup state like ni_txrate */
2078 	if (ic->ic_newassoc != NULL)
2079 		ic->ic_newassoc(ni, newassoc);
2080 	ni->ni_inact_reload = ic->ic_inact_auth;
2081 	ni->ni_inact = ni->ni_inact_reload;
2082 	IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
2083 	/* tell the authenticator about new station */
2084 	if (ic->ic_auth->ia_node_join != NULL)
2085 		ic->ic_auth->ia_node_join(ic, ni);
2086 	ieee80211_notify_node_join(ic, ni, newassoc);
2087 }
2088 
2089 /*
2090  * Handle a station leaving an 11g network.
2091  */
2092 static void
2093 ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
2094 {
2095 
2096 	KASSERT(ic->ic_curmode == IEEE80211_MODE_11G,
2097 	     ("not in 11g, bss %u:0x%x, curmode %u", ni->ni_chan->ic_freq,
2098 	      ni->ni_chan->ic_flags, ic->ic_curmode));
2099 
2100 	/*
2101 	 * If a long slot station do the slot time bookkeeping.
2102 	 */
2103 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
2104 		KASSERT(ic->ic_longslotsta > 0,
2105 		    ("bogus long slot station count %d", ic->ic_longslotsta));
2106 		ic->ic_longslotsta--;
2107 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2108 		    "[%s] long slot time station leaves, count now %d\n",
2109 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
2110 		if (ic->ic_longslotsta == 0) {
2111 			/*
2112 			 * Re-enable use of short slot time if supported
2113 			 * and not operating in IBSS mode (per spec).
2114 			 */
2115 			if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
2116 			    ic->ic_opmode != IEEE80211_M_IBSS) {
2117 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2118 				    "%s: re-enable use of short slot time\n",
2119 				    __func__);
2120 				ieee80211_set_shortslottime(ic, 1);
2121 			}
2122 		}
2123 	}
2124 	/*
2125 	 * If a non-ERP station do the protection-related bookkeeping.
2126 	 */
2127 	if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
2128 		KASSERT(ic->ic_nonerpsta > 0,
2129 		    ("bogus non-ERP station count %d", ic->ic_nonerpsta));
2130 		ic->ic_nonerpsta--;
2131 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2132 		    "[%s] non-ERP station leaves, count now %d\n",
2133 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
2134 		if (ic->ic_nonerpsta == 0) {
2135 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2136 				"%s: disable use of protection\n", __func__);
2137 			ic->ic_flags &= ~IEEE80211_F_USEPROT;
2138 			/* XXX verify mode? */
2139 			if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
2140 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
2141 				    "%s: re-enable use of short preamble\n",
2142 				    __func__);
2143 				ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
2144 				ic->ic_flags &= ~IEEE80211_F_USEBARKER;
2145 			}
2146 		}
2147 	}
2148 }
2149 
2150 /*
2151  * Handle bookkeeping for station deauthentication/disassociation
2152  * when operating as an ap.
2153  */
2154 void
2155 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
2156 {
2157 	struct ieee80211_node_table *nt = ni->ni_table;
2158 
2159 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
2160 	    "[%s] station with aid %d leaves\n",
2161 	    ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
2162 
2163 	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
2164 		ic->ic_opmode == IEEE80211_M_IBSS ||
2165 		ic->ic_opmode == IEEE80211_M_AHDEMO,
2166 		("unexpected operating mode %u", ic->ic_opmode));
2167 	/*
2168 	 * If node wasn't previously associated all
2169 	 * we need to do is reclaim the reference.
2170 	 */
2171 	/* XXX ibss mode bypasses 11g and notification */
2172 	if (ni->ni_associd == 0)
2173 		goto done;
2174 	/*
2175 	 * Tell the authenticator the station is leaving.
2176 	 * Note that we must do this before yanking the
2177 	 * association id as the authenticator uses the
2178 	 * associd to locate it's state block.
2179 	 */
2180 	if (ic->ic_auth->ia_node_leave != NULL)
2181 		ic->ic_auth->ia_node_leave(ic, ni);
2182 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
2183 	ni->ni_associd = 0;
2184 	ic->ic_sta_assoc--;
2185 
2186 	if (ic->ic_curmode == IEEE80211_MODE_11G)
2187 		ieee80211_node_leave_11g(ic, ni);
2188 	/*
2189 	 * Cleanup station state.  In particular clear various
2190 	 * state that might otherwise be reused if the node
2191 	 * is reused before the reference count goes to zero
2192 	 * (and memory is reclaimed).
2193 	 */
2194 	ieee80211_sta_leave(ic, ni);
2195 done:
2196 	/*
2197 	 * Remove the node from any table it's recorded in and
2198 	 * drop the caller's reference.  Removal from the table
2199 	 * is important to insure the node is not reprocessed
2200 	 * for inactivity.
2201 	 */
2202 	if (nt != NULL) {
2203 		IEEE80211_NODE_LOCK(nt);
2204 		node_reclaim(nt, ni);
2205 		IEEE80211_NODE_UNLOCK(nt);
2206 	} else
2207 		ieee80211_free_node(ni);
2208 }
2209 
2210 u_int8_t
2211 ieee80211_getrssi(struct ieee80211com *ic)
2212 {
2213 #define	NZ(x)	((x) == 0 ? 1 : (x))
2214 	struct ieee80211_node_table *nt = &ic->ic_sta;
2215 	u_int32_t rssi_samples, rssi_total;
2216 	struct ieee80211_node *ni;
2217 
2218 	rssi_total = 0;
2219 	rssi_samples = 0;
2220 	switch (ic->ic_opmode) {
2221 	case IEEE80211_M_IBSS:		/* average of all ibss neighbors */
2222 		/* XXX locking */
2223 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
2224 			if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
2225 				rssi_samples++;
2226 				rssi_total += ic->ic_node_getrssi(ni);
2227 			}
2228 		break;
2229 	case IEEE80211_M_AHDEMO:	/* average of all neighbors */
2230 		/* XXX locking */
2231 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
2232 			rssi_samples++;
2233 			rssi_total += ic->ic_node_getrssi(ni);
2234 		}
2235 		break;
2236 	case IEEE80211_M_HOSTAP:	/* average of all associated stations */
2237 		/* XXX locking */
2238 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
2239 			if (IEEE80211_AID(ni->ni_associd) != 0) {
2240 				rssi_samples++;
2241 				rssi_total += ic->ic_node_getrssi(ni);
2242 			}
2243 		break;
2244 	case IEEE80211_M_MONITOR:	/* XXX */
2245 	case IEEE80211_M_STA:		/* use stats from associated ap */
2246 	default:
2247 		if (ic->ic_bss != NULL)
2248 			rssi_total = ic->ic_node_getrssi(ic->ic_bss);
2249 		rssi_samples = 1;
2250 		break;
2251 	}
2252 	return rssi_total / NZ(rssi_samples);
2253 #undef NZ
2254 }
2255 
2256 /*
2257  * Indicate whether there are frames queued for a station in power-save mode.
2258  */
2259 static void
2260 ieee80211_set_tim(struct ieee80211_node *ni, int set)
2261 {
2262 	struct ieee80211com *ic = ni->ni_ic;
2263 	u_int16_t aid;
2264 
2265 	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
2266 		ic->ic_opmode == IEEE80211_M_IBSS,
2267 		("operating mode %u", ic->ic_opmode));
2268 
2269 	aid = IEEE80211_AID(ni->ni_associd);
2270 	KASSERT(aid < ic->ic_max_aid,
2271 		("bogus aid %u, max %u", aid, ic->ic_max_aid));
2272 
2273 	IEEE80211_BEACON_LOCK(ic);
2274 	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
2275 		if (set) {
2276 			setbit(ic->ic_tim_bitmap, aid);
2277 			ic->ic_ps_pending++;
2278 		} else {
2279 			clrbit(ic->ic_tim_bitmap, aid);
2280 			ic->ic_ps_pending--;
2281 		}
2282 		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
2283 	}
2284 	IEEE80211_BEACON_UNLOCK(ic);
2285 }
2286 
2287 /*
2288  * Node table support.
2289  */
2290 
2291 static void
2292 ieee80211_node_table_init(struct ieee80211com *ic,
2293 	struct ieee80211_node_table *nt,
2294 	const char *name, int inact, int keyixmax,
2295 	void (*timeout)(struct ieee80211_node_table *))
2296 {
2297 
2298 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
2299 		"%s %s table, inact %u\n", __func__, name, inact);
2300 
2301 	nt->nt_ic = ic;
2302 	/* XXX need unit */
2303 	IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
2304 	IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
2305 	TAILQ_INIT(&nt->nt_node);
2306 	nt->nt_name = name;
2307 	nt->nt_scangen = 1;
2308 	nt->nt_inact_init = inact;
2309 	nt->nt_timeout = timeout;
2310 	nt->nt_keyixmax = keyixmax;
2311 	if (nt->nt_keyixmax > 0) {
2312 		MALLOC(nt->nt_keyixmap, struct ieee80211_node **,
2313 			keyixmax * sizeof(struct ieee80211_node *),
2314 			M_80211_NODE, M_NOWAIT | M_ZERO);
2315 		if (nt->nt_keyixmap == NULL)
2316 			if_printf(ic->ic_ifp,
2317 			    "Cannot allocate key index map with %u entries\n",
2318 			    keyixmax);
2319 	} else
2320 		nt->nt_keyixmap = NULL;
2321 }
2322 
2323 void
2324 ieee80211_node_table_reset(struct ieee80211_node_table *nt)
2325 {
2326 
2327 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2328 		"%s %s table\n", __func__, nt->nt_name);
2329 
2330 	IEEE80211_NODE_LOCK(nt);
2331 	nt->nt_inact_timer = 0;
2332 	ieee80211_free_allnodes_locked(nt);
2333 	IEEE80211_NODE_UNLOCK(nt);
2334 }
2335 
2336 static void
2337 ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
2338 {
2339 
2340 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2341 		"%s %s table\n", __func__, nt->nt_name);
2342 
2343 	IEEE80211_NODE_LOCK(nt);
2344 	ieee80211_free_allnodes_locked(nt);
2345 	if (nt->nt_keyixmap != NULL) {
2346 		/* XXX verify all entries are NULL */
2347 		int i;
2348 		for (i = 0; i < nt->nt_keyixmax; i++)
2349 			if (nt->nt_keyixmap[i] != NULL)
2350 				printf("%s: %s[%u] still active\n", __func__,
2351 					nt->nt_name, i);
2352 		FREE(nt->nt_keyixmap, M_80211_NODE);
2353 		nt->nt_keyixmap = NULL;
2354 	}
2355 	IEEE80211_SCAN_LOCK_DESTROY(nt);
2356 	IEEE80211_NODE_LOCK_DESTROY(nt);
2357 }
2358