xref: /netbsd-src/sys/net80211/ieee80211_node.c (revision df0caa2637da0538ecdf6b878c4d08e684b43d8f)
1 /*	$NetBSD: ieee80211_node.c,v 1.40 2005/06/26 04:31:51 dyoung Exp $	*/
2 /*-
3  * Copyright (c) 2001 Atsushi Onoe
4  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * Alternatively, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2 as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifdef __FreeBSD__
36 __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_node.c,v 1.43 2005/02/10 16:59:04 sam Exp $");
37 #endif
38 #ifdef __NetBSD__
39 __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.40 2005/06/26 04:31:51 dyoung Exp $");
40 #endif
41 
42 #include "opt_inet.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/mbuf.h>
47 #include <sys/malloc.h>
48 #include <sys/kernel.h>
49 
50 #include <sys/socket.h>
51 #include <sys/sockio.h>
52 #include <sys/endian.h>
53 #include <sys/errno.h>
54 #include <sys/proc.h>
55 #include <sys/sysctl.h>
56 
57 #include <net/if.h>
58 #include <net/if_media.h>
59 #include <net/if_arp.h>
60 #include <net/if_ether.h>
61 #include <net/if_llc.h>
62 
63 #include <net80211/ieee80211_netbsd.h>
64 #include <net80211/ieee80211_var.h>
65 
66 #include <net/bpf.h>
67 
68 #ifdef INET
69 #include <netinet/in.h>
70 #include <net/if_ether.h>
71 #endif
72 
73 static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
74 static void node_cleanup(struct ieee80211_node *);
75 static void node_free(struct ieee80211_node *);
76 static u_int8_t node_getrssi(const struct ieee80211_node *);
77 
78 static void ieee80211_setup_node(struct ieee80211_node_table *,
79 		struct ieee80211_node *, const u_int8_t *);
80 static void _ieee80211_free_node(struct ieee80211_node *);
81 static void ieee80211_free_allnodes(struct ieee80211_node_table *);
82 
83 static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
84 static void ieee80211_timeout_stations(struct ieee80211_node_table *);
85 
86 static void ieee80211_set_tim(struct ieee80211com *,
87 		struct ieee80211_node *, int set);
88 
89 static void ieee80211_node_table_init(struct ieee80211com *ic,
90 	struct ieee80211_node_table *nt, const char *name, int inact,
91 	void (*timeout)(struct ieee80211_node_table *));
92 static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
93 
94 MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
95 
96 void
97 ieee80211_node_attach(struct ieee80211com *ic)
98 {
99 	u_long sz;
100 
101 	ieee80211_node_table_init(ic, &ic->ic_sta, "station",
102 		IEEE80211_INACT_INIT, ieee80211_timeout_stations);
103 	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
104 		IEEE80211_INACT_SCAN, ieee80211_timeout_scan_candidates);
105 
106 	ic->ic_node_alloc = node_alloc;
107 	ic->ic_node_free = node_free;
108 	ic->ic_node_cleanup = node_cleanup;
109 	ic->ic_node_getrssi = node_getrssi;
110 
111 	/* default station inactivity timer setings */
112 	ic->ic_inact_init = IEEE80211_INACT_INIT;
113 	ic->ic_inact_auth = IEEE80211_INACT_AUTH;
114 	ic->ic_inact_run = IEEE80211_INACT_RUN;
115 	ic->ic_inact_probe = IEEE80211_INACT_PROBE;
116 
117 	/* XXX defer */
118 	if (ic->ic_max_aid == 0)
119 		ic->ic_max_aid = IEEE80211_AID_DEF;
120 	else if (ic->ic_max_aid > IEEE80211_AID_MAX)
121 		ic->ic_max_aid = IEEE80211_AID_MAX;
122 	MALLOC(ic->ic_aid_bitmap, u_int32_t *,
123 		howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
124 		M_DEVBUF, M_NOWAIT | M_ZERO);
125 	if (ic->ic_aid_bitmap == NULL) {
126 		/* XXX no way to recover */
127 		printf("%s: no memory for AID bitmap!\n", __func__);
128 		ic->ic_max_aid = 0;
129 	}
130 
131 	/* XXX defer until using hostap/ibss mode */
132 	ic->ic_tim_len = sz = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
133 	MALLOC(ic->ic_tim_bitmap, u_int8_t *, sz, M_DEVBUF, M_NOWAIT | M_ZERO);
134 	if (ic->ic_tim_bitmap == NULL) {
135 		/* XXX no way to recover */
136 		printf("%s: no memory for TIM bitmap!\n", __func__);
137 	}
138 	ic->ic_set_tim = ieee80211_set_tim;	/* NB: driver should override */
139 }
140 
141 void
142 ieee80211_node_lateattach(struct ieee80211com *ic)
143 {
144 	struct ieee80211_node *ni;
145 	struct ieee80211_rsnparms *rsn;
146 
147 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
148 	IASSERT(ni != NULL, ("unable to setup inital BSS node"));
149 	/*
150 	 * Setup "global settings" in the bss node so that
151 	 * each new station automatically inherits them.
152 	 */
153 	rsn = &ni->ni_rsn;
154 	/* WEP, TKIP, and AES-CCM are always supported */
155 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
156 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
157 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
158 	if (ic->ic_caps & IEEE80211_C_AES)
159 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
160 	if (ic->ic_caps & IEEE80211_C_CKIP)
161 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
162 	/*
163 	 * Default unicast cipher to WEP for 802.1x use.  If
164 	 * WPA is enabled the management code will set these
165 	 * values to reflect.
166 	 */
167 	rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
168 	rsn->rsn_ucastkeylen = 104 / NBBY;
169 	/*
170 	 * WPA says the multicast cipher is the lowest unicast
171 	 * cipher supported.  But we skip WEP which would
172 	 * otherwise be used based on this criteria.
173 	 */
174 	rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
175 	rsn->rsn_mcastkeylen = 128 / NBBY;
176 
177 	/*
178 	 * We support both WPA-PSK and 802.1x; the one used
179 	 * is determined by the authentication mode and the
180 	 * setting of the PSK state.
181 	 */
182 	rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
183 	rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
184 
185 	ic->ic_bss = ieee80211_ref_node(ni);		/* hold reference */
186 	ic->ic_auth = ieee80211_authenticator_get(ni->ni_authmode);
187 }
188 
189 void
190 ieee80211_node_detach(struct ieee80211com *ic)
191 {
192 
193 	if (ic->ic_bss != NULL) {
194 		ieee80211_free_node(ic->ic_bss);
195 		ic->ic_bss = NULL;
196 	}
197 	ieee80211_node_table_cleanup(&ic->ic_scan);
198 	ieee80211_node_table_cleanup(&ic->ic_sta);
199 	if (ic->ic_aid_bitmap != NULL) {
200 		FREE(ic->ic_aid_bitmap, M_DEVBUF);
201 		ic->ic_aid_bitmap = NULL;
202 	}
203 	if (ic->ic_tim_bitmap != NULL) {
204 		FREE(ic->ic_tim_bitmap, M_DEVBUF);
205 		ic->ic_tim_bitmap = NULL;
206 	}
207 }
208 
209 /*
210  * Port authorize/unauthorize interfaces for use by an authenticator.
211  */
212 
213 void
214 ieee80211_node_authorize(struct ieee80211com *ic, struct ieee80211_node *ni)
215 {
216 	ni->ni_flags |= IEEE80211_NODE_AUTH;
217 	ni->ni_inact_reload = ic->ic_inact_run;
218 }
219 
220 void
221 ieee80211_node_unauthorize(struct ieee80211com *ic, struct ieee80211_node *ni)
222 {
223 	ni->ni_flags &= ~IEEE80211_NODE_AUTH;
224 }
225 
226 /*
227  * Set/change the channel.  The rate set is also updated as
228  * to insure a consistent view by drivers.
229  */
230 static __inline void
231 ieee80211_set_chan(struct ieee80211com *ic,
232 	struct ieee80211_node *ni, struct ieee80211_channel *chan)
233 {
234 	ni->ni_chan = chan;
235 	ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
236 }
237 
238 /*
239  * AP scanning support.
240  */
241 
242 #ifdef IEEE80211_DEBUG
243 static void
244 dump_chanlist(const u_char chans[])
245 {
246 	const char *sep;
247 	int i;
248 
249 	sep = " ";
250 	for (i = 0; i < IEEE80211_CHAN_MAX; i++)
251 		if (isset(chans, i)) {
252 			printf("%s%u", sep, i);
253 			sep = ", ";
254 		}
255 }
256 #endif /* IEEE80211_DEBUG */
257 
258 /*
259  * Initialize the channel set to scan based on the
260  * of available channels and the current PHY mode.
261  */
262 static void
263 ieee80211_reset_scan(struct ieee80211com *ic)
264 {
265 
266 	/* XXX ic_des_chan should be handled with ic_chan_active */
267 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
268 		memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
269 		setbit(ic->ic_chan_scan,
270 			ieee80211_chan2ieee(ic, ic->ic_des_chan));
271 	} else
272 		memcpy(ic->ic_chan_scan, ic->ic_chan_active,
273 			sizeof(ic->ic_chan_active));
274 	/* NB: hack, setup so next_scan starts with the first channel */
275 	if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC)
276 		ieee80211_set_chan(ic, ic->ic_bss,
277 			&ic->ic_channels[IEEE80211_CHAN_MAX]);
278 #ifdef IEEE80211_DEBUG
279 	if (ieee80211_msg_scan(ic)) {
280 		printf("%s: scan set:", __func__);
281 		dump_chanlist(ic->ic_chan_scan);
282 		printf(" start chan %u\n",
283 			ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan));
284 	}
285 #endif /* IEEE80211_DEBUG */
286 }
287 
288 /*
289  * Begin an active scan.
290  */
291 void
292 ieee80211_begin_scan(struct ieee80211com *ic, int reset)
293 {
294 
295 	ic->ic_scan.nt_scangen++;
296 	/*
297 	 * In all but hostap mode scanning starts off in
298 	 * an active mode before switching to passive.
299 	 */
300 	if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
301 		ic->ic_flags |= IEEE80211_F_ASCAN;
302 		ic->ic_stats.is_scan_active++;
303 	} else
304 		ic->ic_stats.is_scan_passive++;
305 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
306 		"begin %s scan in %s mode, scangen %u\n",
307 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
308 		ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
309 	/*
310 	 * Clear scan state and flush any previously seen AP's.
311 	 */
312 	ieee80211_reset_scan(ic);
313 	if (reset)
314 		ieee80211_free_allnodes(&ic->ic_scan);
315 
316 	ic->ic_flags |= IEEE80211_F_SCAN;
317 
318 	/* Scan the next channel. */
319 	ieee80211_next_scan(ic);
320 }
321 
322 /*
323  * Switch to the next channel marked for scanning.
324  */
325 int
326 ieee80211_next_scan(struct ieee80211com *ic)
327 {
328 	struct ieee80211_channel *chan;
329 
330 	/*
331 	 * Insure any previous mgt frame timeouts don't fire.
332 	 * This assumes the driver does the right thing in
333 	 * flushing anything queued in the driver and below.
334 	 */
335 	ic->ic_mgt_timer = 0;
336 
337 	chan = ic->ic_bss->ni_chan;
338 	do {
339 		if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
340 			chan = &ic->ic_channels[0];
341 		if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
342 			clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
343 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
344 			    "%s: chan %d->%d\n", __func__,
345 			    ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan),
346 			    ieee80211_chan2ieee(ic, chan));
347 			ieee80211_set_chan(ic, ic->ic_bss, chan);
348 #ifdef notyet
349 			/* XXX driver state change */
350 			/*
351 			 * Scan next channel. If doing an active scan
352 			 * and the channel is not marked passive-only
353 			 * then send a probe request.  Otherwise just
354 			 * listen for beacons on the channel.
355 			 */
356 			if ((ic->ic_flags & IEEE80211_F_ASCAN) &&
357 			    (ni->ni_chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) {
358 				IEEE80211_SEND_MGMT(ic, ni,
359 				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
360 			}
361 #else
362 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
363 #endif
364 			return 1;
365 		}
366 	} while (chan != ic->ic_bss->ni_chan);
367 	ieee80211_end_scan(ic);
368 	return 0;
369 }
370 
371 static __inline void
372 copy_bss(struct ieee80211_node *nbss, const struct ieee80211_node *obss)
373 {
374 	/* propagate useful state */
375 	nbss->ni_authmode = obss->ni_authmode;
376 	nbss->ni_txpower = obss->ni_txpower;
377 	nbss->ni_vlan = obss->ni_vlan;
378 	nbss->ni_rsn = obss->ni_rsn;
379 	/* XXX statistics? */
380 }
381 
382 void
383 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
384 {
385 	struct ieee80211_node_table *nt;
386 	struct ieee80211_node *ni;
387 
388 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
389 		"%s: creating ibss\n", __func__);
390 
391 	/*
392 	 * Create the station/neighbor table.  Note that for adhoc
393 	 * mode we make the initial inactivity timer longer since
394 	 * we create nodes only through discovery and they typically
395 	 * are long-lived associations.
396 	 */
397 	nt = &ic->ic_sta;
398 	IEEE80211_NODE_LOCK(nt);
399 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
400 		nt->nt_name = "station";
401 		nt->nt_inact_init = ic->ic_inact_init;
402 	} else {
403 		nt->nt_name = "neighbor";
404 		nt->nt_inact_init = ic->ic_inact_run;
405 	}
406 	IEEE80211_NODE_UNLOCK(nt);
407 
408 	ni = ieee80211_alloc_node(nt, ic->ic_myaddr);
409 	if (ni == NULL) {
410 		/* XXX recovery? */
411 		return;
412 	}
413 	if (ic->ic_opmode != IEEE80211_M_HOSTAP &&
414 	    (ic->ic_flags & IEEE80211_F_DESBSSID) != 0)
415 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
416 	else
417 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
418 	ni->ni_esslen = ic->ic_des_esslen;
419 	memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
420 	copy_bss(ni, ic->ic_bss);
421 	ni->ni_intval = ic->ic_lintval;
422 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
423 		ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
424 	if (ic->ic_phytype == IEEE80211_T_FH) {
425 		ni->ni_fhdwell = 200;	/* XXX */
426 		ni->ni_fhindex = 1;
427 	}
428 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
429 		ic->ic_flags |= IEEE80211_F_SIBSS;
430 		ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;	/* XXX */
431 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
432 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
433 		else
434 		ni->ni_bssid[0] |= 0x02;	/* local bit for IBSS */
435 	}
436 	/*
437 	 * Fix the channel and related attributes.
438 	 */
439 	ieee80211_set_chan(ic, ni, chan);
440 	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
441 	/*
442 	 * Do mode-specific rate setup.
443 	 */
444 	if (ic->ic_curmode == IEEE80211_MODE_11G) {
445 		/*
446 		 * Use a mixed 11b/11g rate set.
447 		 */
448 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
449 	} else if (ic->ic_curmode == IEEE80211_MODE_11B) {
450 		/*
451 		 * Force pure 11b rate set.
452 		 */
453 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
454 	}
455 
456 	(void) ieee80211_sta_join(ic, ieee80211_ref_node(ni));
457 }
458 
459 void
460 ieee80211_reset_bss(struct ieee80211com *ic)
461 {
462 	struct ieee80211_node *ni, *obss;
463 
464 	ieee80211_node_table_reset(&ic->ic_scan);
465 	ieee80211_node_table_reset(&ic->ic_sta);
466 
467 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
468 	IASSERT(ni != NULL, ("unable to setup inital BSS node"));
469 	obss = ic->ic_bss;
470 	ic->ic_bss = ieee80211_ref_node(ni);
471 	if (obss != NULL) {
472 		copy_bss(ni, obss);
473 		ni->ni_intval = ic->ic_lintval;
474 		ieee80211_free_node(obss);
475 	}
476 }
477 
478 static int
479 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
480 {
481         u_int8_t rate;
482         int fail;
483 
484 	fail = 0;
485 	if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
486 		fail |= 0x01;
487 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
488 	    ni->ni_chan != ic->ic_des_chan)
489 		fail |= 0x01;
490 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
491 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
492 			fail |= 0x02;
493 	} else {
494 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
495 			fail |= 0x02;
496 	}
497 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
498 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
499 			fail |= 0x04;
500 	} else {
501 		/* XXX does this mean privacy is supported or required? */
502 		if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
503 			fail |= 0x04;
504 	}
505 	rate = ieee80211_fix_rate(ic, ni,
506 			IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
507 	if (rate & IEEE80211_RATE_BASIC)
508 		fail |= 0x08;
509 	if (ic->ic_des_esslen != 0 &&
510 	    (ni->ni_esslen != ic->ic_des_esslen ||
511 	     memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
512 		fail |= 0x10;
513 	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
514 	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
515 		fail |= 0x20;
516 #ifdef IEEE80211_DEBUG
517 	if (ieee80211_msg_scan(ic)) {
518 		printf(" %c %s", fail ? '-' : '+',
519 		    ether_sprintf(ni->ni_macaddr));
520 		printf(" %s%c", ether_sprintf(ni->ni_bssid),
521 		    fail & 0x20 ? '!' : ' ');
522 		printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
523 			fail & 0x01 ? '!' : ' ');
524 		printf(" %+4d", ni->ni_rssi);
525 		printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
526 		    fail & 0x08 ? '!' : ' ');
527 		printf(" %4s%c",
528 		    (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
529 		    (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
530 		    "????",
531 		    fail & 0x02 ? '!' : ' ');
532 		printf(" %3s%c ",
533 		    (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
534 		    "wep" : "no",
535 		    fail & 0x04 ? '!' : ' ');
536 		ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
537 		printf("%s\n", fail & 0x10 ? "!" : "");
538 	}
539 #endif
540 	return fail;
541 }
542 
543 static __inline u_int8_t
544 maxrate(const struct ieee80211_node *ni)
545 {
546 	const struct ieee80211_rateset *rs = &ni->ni_rates;
547 	/* NB: assumes rate set is sorted (happens on frame receive) */
548 	return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
549 }
550 
551 /*
552  * Compare the capabilities of two nodes and decide which is
553  * more desirable (return >0 if a is considered better).  Note
554  * that we assume compatibility/usability has already been checked
555  * so we don't need to (e.g. validate whether privacy is supported).
556  * Used to select the best scan candidate for association in a BSS.
557  */
558 static int
559 ieee80211_node_compare(struct ieee80211com *ic,
560 		       const struct ieee80211_node *a,
561 		       const struct ieee80211_node *b)
562 {
563 	u_int8_t maxa, maxb;
564 	u_int8_t rssia, rssib;
565 
566 	/* privacy support preferred */
567 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
568 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
569 		return 1;
570 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
571 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
572 		return -1;
573 
574 	rssia = ic->ic_node_getrssi(a);
575 	rssib = ic->ic_node_getrssi(b);
576 	if (abs(rssib - rssia) < 5) {
577 		/* best/max rate preferred if signal level close enough XXX */
578 		maxa = maxrate(a);
579 		maxb = maxrate(b);
580 		if (maxa != maxb)
581 			return maxa - maxb;
582 		/* XXX use freq for channel preference */
583 		/* for now just prefer 5Ghz band to all other bands */
584 		if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
585 		   !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
586 			return 1;
587 		if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
588 		     IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
589 			return -1;
590 	}
591 	/* all things being equal, use signal level */
592 	return rssia - rssib;
593 }
594 
595 /*
596  * Mark an ongoing scan stopped.
597  */
598 void
599 ieee80211_cancel_scan(struct ieee80211com *ic)
600 {
601 
602 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
603 		__func__,
604 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
605 
606 	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
607 }
608 
609 /*
610  * Complete a scan of potential channels.
611  */
612 void
613 ieee80211_end_scan(struct ieee80211com *ic)
614 {
615 	struct ieee80211_node_table *nt = &ic->ic_scan;
616 	struct ieee80211_node *ni, *selbs;
617 
618 	ieee80211_cancel_scan(ic);
619 	ieee80211_notify_scan_done(ic);
620 
621 #ifndef IEEE80211_NO_HOSTAP
622 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
623 		u_int8_t maxrssi[IEEE80211_CHAN_MAX];	/* XXX off stack? */
624 		int i, bestchan;
625 		u_int8_t rssi;
626 
627 		/*
628 		 * The passive scan to look for existing AP's completed,
629 		 * select a channel to camp on.  Identify the channels
630 		 * that already have one or more AP's and try to locate
631 		 * an unoccupied one.  If that fails, pick a channel that
632 		 * looks to be quietest.
633 		 */
634 		memset(maxrssi, 0, sizeof(maxrssi));
635 		IEEE80211_NODE_LOCK(nt);
636 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
637 			rssi = ic->ic_node_getrssi(ni);
638 			i = ieee80211_chan2ieee(ic, ni->ni_chan);
639 			if (rssi > maxrssi[i])
640 				maxrssi[i] = rssi;
641 		}
642 		IEEE80211_NODE_UNLOCK(nt);
643 		/* XXX select channel more intelligently */
644 		bestchan = -1;
645 		for (i = 0; i < IEEE80211_CHAN_MAX; i++)
646 			if (isset(ic->ic_chan_active, i)) {
647 				/*
648 				 * If the channel is unoccupied the max rssi
649 				 * should be zero; just take it.  Otherwise
650 				 * track the channel with the lowest rssi and
651 				 * use that when all channels appear occupied.
652 				 */
653 				if (maxrssi[i] == 0) {
654 					bestchan = i;
655 					break;
656 				}
657 				if (bestchan == -1 ||
658 				    maxrssi[i] < maxrssi[bestchan])
659 					bestchan = i;
660 			}
661 		if (bestchan != -1) {
662 			ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
663 			return;
664 		}
665 		/* no suitable channel, should not happen */
666 	}
667 #endif /* !IEEE80211_NO_HOSTAP */
668 
669 	/*
670 	 * When manually sequencing the state machine; scan just once
671 	 * regardless of whether we have a candidate or not.  The
672 	 * controlling application is expected to setup state and
673 	 * initiate an association.
674 	 */
675 	if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
676 		return;
677 	/*
678 	 * Automatic sequencing; look for a candidate and
679 	 * if found join the network.
680 	 */
681 	/* NB: unlocked read should be ok */
682 	if (TAILQ_FIRST(&nt->nt_node) == NULL) {
683 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
684 			"%s: no scan candidate\n", __func__);
685   notfound:
686 		if (ic->ic_opmode == IEEE80211_M_IBSS &&
687 		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
688 		    ic->ic_des_esslen != 0) {
689 			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
690 			return;
691 		}
692 		/*
693 		 * Reset the list of channels to scan and start again.
694 		 */
695 		ieee80211_reset_scan(ic);
696 		ic->ic_flags |= IEEE80211_F_SCAN;
697 		ieee80211_next_scan(ic);
698 		return;
699 	}
700 	selbs = NULL;
701 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
702 	    "macaddr          bssid         chan  rssi rate flag  wep  essid");
703 	IEEE80211_NODE_LOCK(nt);
704 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
705 		if (ni->ni_fails) {
706 			/*
707 			 * The configuration of the access points may change
708 			 * during my scan.  So delete the entry for the AP
709 			 * and retry to associate if there is another beacon.
710 			 */
711 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
712 				"%s: skip scan candidate %s, fails %u\n",
713 				__func__, ether_sprintf(ni->ni_macaddr),
714 				ni->ni_fails);
715 			ni->ni_fails++;
716 #if 0
717 			if (ni->ni_fails++ > 2)
718 				ieee80211_free_node(ni);
719 #endif
720 			continue;
721 		}
722 		if (ieee80211_match_bss(ic, ni) == 0) {
723 			if (selbs == NULL)
724 				selbs = ni;
725 			else if (ieee80211_node_compare(ic, ni, selbs) > 0)
726 				selbs = ni;
727 		}
728 	}
729 	if (selbs != NULL)		/* NB: grab ref while dropping lock */
730 		(void) ieee80211_ref_node(selbs);
731 	IEEE80211_NODE_UNLOCK(nt);
732 	if (selbs == NULL)
733 		goto notfound;
734 	if (!ieee80211_sta_join(ic, selbs)) {
735 		ieee80211_free_node(selbs);
736 		goto notfound;
737 	}
738 }
739 
740 /*
741  * Handle 802.11 ad hoc network merge.  The
742  * convention, set by the Wireless Ethernet Compatibility Alliance
743  * (WECA), is that an 802.11 station will change its BSSID to match
744  * the "oldest" 802.11 ad hoc network, on the same channel, that
745  * has the station's desired SSID.  The "oldest" 802.11 network
746  * sends beacons with the greatest TSF timestamp.
747  *
748  * The caller is assumed to validate TSF's before attempting a merge.
749  *
750  * Return !0 if the BSSID changed, 0 otherwise.
751  */
752 int
753 ieee80211_ibss_merge(struct ieee80211com *ic, struct ieee80211_node *ni)
754 {
755 
756 	if (ni == ic->ic_bss ||
757 	    IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
758 		/* unchanged, nothing to do */
759 		return 0;
760 	}
761 	if (ieee80211_match_bss(ic, ni) != 0) {	/* capabilities mismatch */
762 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
763 		    "%s: merge failed, capabilities mismatch\n", __func__);
764 		ic->ic_stats.is_ibss_capmismatch++;
765 		return 0;
766 	}
767 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
768 		"%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
769 		ether_sprintf(ni->ni_bssid),
770 		ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
771 		ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
772 		ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
773 	);
774 	return ieee80211_sta_join(ic, ieee80211_ref_node(ni));
775 }
776 
777 /*
778  * Join the specified IBSS/BSS network.  The node is assumed to
779  * be passed in with a held reference.
780  */
781 int
782 ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
783 {
784 	struct ieee80211_node *obss;
785 
786 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
787 		struct ieee80211_node_table *nt;
788 		/*
789 		 * Delete unusable rates; we've already checked
790 		 * that the negotiated rate set is acceptable.
791 		 */
792 		ieee80211_fix_rate(ic, selbs, IEEE80211_F_DODEL);
793 		/*
794 		 * Fillin the neighbor table; it will already
795 		 * exist if we are simply switching mastership.
796 		 * XXX ic_sta always setup so this is unnecessary?
797 		 */
798 		nt = &ic->ic_sta;
799 		IEEE80211_NODE_LOCK(nt);
800 		nt->nt_name = "neighbor";
801 		nt->nt_inact_init = ic->ic_inact_run;
802 		IEEE80211_NODE_UNLOCK(nt);
803 	}
804 
805 	/*
806 	 * Committed to selbs, setup state.
807 	 */
808 	obss = ic->ic_bss;
809 	ic->ic_bss = selbs;		/* NB: caller assumed to bump refcnt */
810 	if (obss != NULL)
811 		ieee80211_free_node(obss);
812 	/*
813 	 * Set the erp state (mostly the slot time) to deal with
814 	 * the auto-select case; this should be redundant if the
815 	 * mode is locked.
816 	 */
817 	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
818 	ieee80211_reset_erp(ic);
819 	ieee80211_wme_initparams(ic);
820 
821 	if (ic->ic_opmode == IEEE80211_M_STA)
822 		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
823 	else
824 		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
825 	return 1;
826 }
827 
828 /*
829  * Leave the specified IBSS/BSS network.  The node is assumed to
830  * be passed in with a held reference.
831  */
832 void
833 ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
834 {
835 	ic->ic_node_cleanup(ni);
836 	ieee80211_notify_node_leave(ic, ni);
837 }
838 
839 int
840 ieee80211_get_rate(struct ieee80211com *ic)
841 {
842 	u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE];
843 	int rate;
844 
845 	rates = &ic->ic_bss->ni_rates.rs_rates;
846 
847 	if (ic->ic_fixed_rate != -1)
848 		rate = (*rates)[ic->ic_fixed_rate];
849 	else if (ic->ic_state == IEEE80211_S_RUN)
850 		rate = (*rates)[ic->ic_bss->ni_txrate];
851 	else
852 		rate = 0;
853 
854 	return rate & IEEE80211_RATE_VAL;
855 }
856 
857 static struct ieee80211_node *
858 node_alloc(struct ieee80211_node_table *nt)
859 {
860 	struct ieee80211_node *ni;
861 
862 	MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
863 		M_80211_NODE, M_NOWAIT | M_ZERO);
864 	return ni;
865 }
866 
867 /*
868  * Reclaim any resources in a node and reset any critical
869  * state.  Typically nodes are free'd immediately after,
870  * but in some cases the storage may be reused so we need
871  * to insure consistent state (should probably fix that).
872  */
873 static void
874 node_cleanup(struct ieee80211_node *ni)
875 {
876 #define	N(a)	(sizeof(a)/sizeof(a[0]))
877 	struct ieee80211com *ic = ni->ni_ic;
878 	int i, qlen;
879 
880 	/* NB: preserve ni_table */
881 	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
882 		ic->ic_ps_sta--;
883 		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
884 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
885 		    "[%s] power save mode off, %u sta's in ps mode\n",
886 		    ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
887 	}
888 
889 	/*
890 	 * Drain power save queue and, if needed, clear TIM.
891 	 */
892 	IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
893 	if (qlen != 0 && ic->ic_set_tim != NULL)
894 		ic->ic_set_tim(ic, ni, 0);
895 
896 	ni->ni_associd = 0;
897 	if (ni->ni_challenge != NULL) {
898 		FREE(ni->ni_challenge, M_DEVBUF);
899 		ni->ni_challenge = NULL;
900 	}
901 	/*
902 	 * Preserve SSID, WPA, and WME ie's so the bss node is
903 	 * reusable during a re-auth/re-assoc state transition.
904 	 * If we remove these data they will not be recreated
905 	 * because they come from a probe-response or beacon frame
906 	 * which cannot be expected prior to the association-response.
907 	 * This should not be an issue when operating in other modes
908 	 * as stations leaving always go through a full state transition
909 	 * which will rebuild this state.
910 	 *
911 	 * XXX does this leave us open to inheriting old state?
912 	 */
913 	for (i = 0; i < N(ni->ni_rxfrag); i++)
914 		if (ni->ni_rxfrag[i] != NULL) {
915 			m_freem(ni->ni_rxfrag[i]);
916 			ni->ni_rxfrag[i] = NULL;
917 		}
918 	ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
919 #undef N
920 }
921 
922 static void
923 node_free(struct ieee80211_node *ni)
924 {
925 	struct ieee80211com *ic = ni->ni_ic;
926 
927 	ic->ic_node_cleanup(ni);
928 	if (ni->ni_wpa_ie != NULL)
929 		FREE(ni->ni_wpa_ie, M_DEVBUF);
930 	if (ni->ni_wme_ie != NULL)
931 		FREE(ni->ni_wme_ie, M_DEVBUF);
932 	IEEE80211_NODE_SAVEQ_DESTROY(ni);
933 	FREE(ni, M_80211_NODE);
934 }
935 
936 static u_int8_t
937 node_getrssi(const struct ieee80211_node *ni)
938 {
939 	return ni->ni_rssi;
940 }
941 
942 static void
943 ieee80211_setup_node(struct ieee80211_node_table *nt,
944 	struct ieee80211_node *ni, const u_int8_t *macaddr)
945 {
946 	struct ieee80211com *ic = nt->nt_ic;
947 	int hash;
948 
949 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
950 		"%s %p<%s> in %s table\n", __func__, ni,
951 		ether_sprintf(macaddr), nt->nt_name);
952 
953 	IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
954 	hash = IEEE80211_NODE_HASH(macaddr);
955 	ieee80211_node_initref(ni);		/* mark referenced */
956 	ni->ni_chan = IEEE80211_CHAN_ANYC;
957 	ni->ni_authmode = IEEE80211_AUTH_OPEN;
958 	ni->ni_txpower = ic->ic_txpowlimit;	/* max power */
959 	ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
960 	ni->ni_inact_reload = nt->nt_inact_init;
961 	ni->ni_inact = ni->ni_inact_reload;
962 	IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
963 
964 	IEEE80211_NODE_LOCK(nt);
965 	TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
966 	LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
967 	ni->ni_table = nt;
968 	ni->ni_ic = ic;
969 	IEEE80211_NODE_UNLOCK(nt);
970 }
971 
972 struct ieee80211_node *
973 ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
974 {
975 	struct ieee80211com *ic = nt->nt_ic;
976 	struct ieee80211_node *ni;
977 
978 	ni = ic->ic_node_alloc(nt);
979 	if (ni != NULL)
980 		ieee80211_setup_node(nt, ni, macaddr);
981 	else
982 		ic->ic_stats.is_rx_nodealloc++;
983 	return ni;
984 }
985 
986 struct ieee80211_node *
987 ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
988 {
989 	struct ieee80211com *ic = nt->nt_ic;
990 	struct ieee80211_node *ni;
991 
992 	ni = ic->ic_node_alloc(nt);
993 	if (ni != NULL) {
994 		ieee80211_setup_node(nt, ni, macaddr);
995 		/*
996 		 * Inherit from ic_bss.
997 		 */
998 		ni->ni_authmode = ic->ic_bss->ni_authmode;
999 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1000 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1001 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
1002 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
1003 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1004 	} else
1005 		ic->ic_stats.is_rx_nodealloc++;
1006 	return ni;
1007 }
1008 
1009 static struct ieee80211_node *
1010 #ifdef IEEE80211_DEBUG_REFCNT
1011 _ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1012 	const u_int8_t *macaddr, const char *func, int line)
1013 #else
1014 _ieee80211_find_node(struct ieee80211_node_table *nt,
1015 	const u_int8_t *macaddr)
1016 #endif
1017 {
1018 	struct ieee80211_node *ni;
1019 	int hash;
1020 
1021 	IEEE80211_NODE_LOCK_ASSERT(nt);
1022 
1023 	hash = IEEE80211_NODE_HASH(macaddr);
1024 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1025 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
1026 			ieee80211_ref_node(ni);	/* mark referenced */
1027 #ifdef IEEE80211_DEBUG_REFCNT
1028 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1029 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1030 			    func, line,
1031 			    ni, ether_sprintf(ni->ni_macaddr),
1032 			    ieee80211_node_refcnt(ni));
1033 #endif
1034 			return ni;
1035 		}
1036 	}
1037 	return NULL;
1038 }
1039 #ifdef IEEE80211_DEBUG_REFCNT
1040 #define	_ieee80211_find_node(nt, mac) \
1041 	_ieee80211_find_node_debug(nt, mac, func, line)
1042 #endif
1043 
1044 struct ieee80211_node *
1045 #ifdef IEEE80211_DEBUG_REFCNT
1046 ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1047 	const u_int8_t *macaddr, const char *func, int line)
1048 #else
1049 ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1050 #endif
1051 {
1052 	struct ieee80211_node *ni;
1053 
1054 	IEEE80211_NODE_LOCK(nt);
1055 	ni = _ieee80211_find_node(nt, macaddr);
1056 	IEEE80211_NODE_UNLOCK(nt);
1057 	return ni;
1058 }
1059 
1060 /*
1061  * Fake up a node; this handles node discovery in adhoc mode.
1062  * Note that for the driver's benefit we we treat this like
1063  * an association so the driver has an opportunity to setup
1064  * it's private state.
1065  */
1066 struct ieee80211_node *
1067 ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
1068 	const u_int8_t macaddr[IEEE80211_ADDR_LEN])
1069 {
1070 	struct ieee80211com *ic = nt->nt_ic;
1071 	struct ieee80211_node *ni;
1072 
1073 	ni = ieee80211_dup_bss(nt, macaddr);
1074 	if (ni != NULL) {
1075 		/* XXX no rate negotiation; just dup */
1076 		ni->ni_rates = ic->ic_bss->ni_rates;
1077 		if (ic->ic_newassoc != NULL)
1078 			ic->ic_newassoc(ic, ni, 1);
1079 		/* XXX not right for 802.1x/WPA */
1080 		ieee80211_node_authorize(ic, ni);
1081 	}
1082 	return ni;
1083 }
1084 
1085 /*
1086  * Locate the node for sender, track state, and then pass the
1087  * (referenced) node up to the 802.11 layer for its use.  We
1088  * are required to pass some node so we fall back to ic_bss
1089  * when this frame is from an unknown sender.  The 802.11 layer
1090  * knows this means the sender wasn't in the node table and
1091  * acts accordingly.
1092  */
1093 struct ieee80211_node *
1094 #ifdef IEEE80211_DEBUG_REFCNT
1095 ieee80211_find_rxnode_debug(struct ieee80211com *ic,
1096 	const struct ieee80211_frame_min *wh, const char *func, int line)
1097 #else
1098 ieee80211_find_rxnode(struct ieee80211com *ic,
1099 	const struct ieee80211_frame_min *wh)
1100 #endif
1101 {
1102 #define	IS_CTL(wh) \
1103 	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1104 #define	IS_PSPOLL(wh) \
1105 	((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
1106 	struct ieee80211_node_table *nt;
1107 	struct ieee80211_node *ni;
1108 
1109 	/* XXX may want scanned nodes in the neighbor table for adhoc */
1110 	if (ic->ic_opmode == IEEE80211_M_STA ||
1111 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1112 	    (ic->ic_flags & IEEE80211_F_SCAN))
1113 		nt = &ic->ic_scan;
1114 	else
1115 		nt = &ic->ic_sta;
1116 	/* XXX check ic_bss first in station mode */
1117 	/* XXX 4-address frames? */
1118 	IEEE80211_NODE_LOCK(nt);
1119 	if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1120 		ni = _ieee80211_find_node(nt, wh->i_addr1);
1121 	else
1122 		ni = _ieee80211_find_node(nt, wh->i_addr2);
1123 	IEEE80211_NODE_UNLOCK(nt);
1124 
1125 	return (ni != NULL ? ni : ieee80211_ref_node(ic->ic_bss));
1126 #undef IS_PSPOLL
1127 #undef IS_CTL
1128 }
1129 
1130 /*
1131  * Return a reference to the appropriate node for sending
1132  * a data frame.  This handles node discovery in adhoc networks.
1133  */
1134 struct ieee80211_node *
1135 #ifdef IEEE80211_DEBUG_REFCNT
1136 ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
1137 	const char *func, int line)
1138 #else
1139 ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
1140 #endif
1141 {
1142 	struct ieee80211_node_table *nt = &ic->ic_sta;
1143 	struct ieee80211_node *ni;
1144 
1145 	/*
1146 	 * The destination address should be in the node table
1147 	 * unless we are operating in station mode or this is a
1148 	 * multicast/broadcast frame.
1149 	 */
1150 	if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
1151 		return ieee80211_ref_node(ic->ic_bss);
1152 
1153 	/* XXX can't hold lock across dup_bss 'cuz of recursive locking */
1154 	IEEE80211_NODE_LOCK(nt);
1155 	ni = _ieee80211_find_node(nt, macaddr);
1156 	IEEE80211_NODE_UNLOCK(nt);
1157 
1158 	if (ni == NULL) {
1159 		if (ic->ic_opmode == IEEE80211_M_IBSS ||
1160 		    ic->ic_opmode == IEEE80211_M_AHDEMO) {
1161 			/*
1162 			 * In adhoc mode cons up a node for the destination.
1163 			 * Note that we need an additional reference for the
1164 			 * caller to be consistent with _ieee80211_find_node.
1165 			 */
1166 			ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
1167 			if (ni != NULL)
1168 				(void) ieee80211_ref_node(ni);
1169 		} else {
1170 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
1171 				"[%s] no node, discard frame (%s)\n",
1172 				ether_sprintf(macaddr), __func__);
1173 			ic->ic_stats.is_tx_nonode++;
1174 		}
1175 	}
1176 	return ni;
1177 }
1178 
1179 /*
1180  * Like find but search based on the channel too.
1181  */
1182 struct ieee80211_node *
1183 #ifdef IEEE80211_DEBUG_REFCNT
1184 ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
1185 	const u_int8_t *macaddr, struct ieee80211_channel *chan,
1186 	const char *func, int line)
1187 #else
1188 ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
1189 	const u_int8_t *macaddr, struct ieee80211_channel *chan)
1190 #endif
1191 {
1192 	struct ieee80211_node *ni;
1193 	int hash;
1194 
1195 	hash = IEEE80211_NODE_HASH(macaddr);
1196 	IEEE80211_NODE_LOCK(nt);
1197 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1198 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1199 		    ni->ni_chan == chan) {
1200 			ieee80211_ref_node(ni);		/* mark referenced */
1201 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1202 #ifdef IEEE80211_DEBUG_REFCNT
1203 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1204 			    func, line,
1205 #else
1206 			    "%s %p<%s> refcnt %d\n", __func__,
1207 #endif
1208 			    ni, ether_sprintf(ni->ni_macaddr),
1209 			    ieee80211_node_refcnt(ni));
1210 			break;
1211 		}
1212 	}
1213 	IEEE80211_NODE_UNLOCK(nt);
1214 	return ni;
1215 }
1216 
1217 struct ieee80211_node *
1218 ieee80211_refine_node_for_beacon(struct ieee80211com *ic,
1219 	struct ieee80211_node *ni0, struct ieee80211_channel *chan,
1220 	const u_int8_t *ssid)
1221 {
1222 	struct ieee80211_node_table *nt = ni0->ni_table;
1223 	struct ieee80211_node *best, *ni;
1224 	int best_score = 0, score;
1225 
1226 	best = ni0;
1227 	if (ssid[1] == 0 || best->ni_esslen == 0)
1228 		best_score = 1;
1229 	else if (ssid[1] == best->ni_esslen &&
1230 		 memcmp(ssid + 2, best->ni_essid, ssid[1]) == 0)
1231 		best_score = 2;
1232 	else
1233 		best_score = 0;
1234 
1235 	IEEE80211_NODE_LOCK(nt);
1236 	for (ni = LIST_NEXT(ni0, ni_hash); ni != NULL;
1237 	     ni = LIST_NEXT(ni, ni_hash)) {
1238 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, best->ni_macaddr) ||
1239 		    ni->ni_ic != best->ni_ic || ni->ni_chan != chan)
1240 			continue;
1241 
1242 		if (ssid[1] == 0 || ni->ni_esslen == 0)
1243 			score = 1;
1244 		else if (ssid[1] == ni->ni_esslen &&
1245 			 memcmp(ssid + 2, ni->ni_essid, ssid[1]) == 0)
1246 			score = 2;
1247 		else
1248 			continue;
1249 
1250 		if (score > best_score) {
1251 			ieee80211_ref_node(ni);
1252 			ieee80211_unref_node(&best);
1253 			best = ni;
1254 			best_score = score;
1255 		}
1256 	}
1257 	IEEE80211_NODE_UNLOCK(nt);
1258 	return best;
1259 }
1260 
1261 /*
1262  * Like find but search based on the ssid too.
1263  */
1264 struct ieee80211_node *
1265 #ifdef IEEE80211_DEBUG_REFCNT
1266 ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
1267 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
1268 	const char *func, int line)
1269 #else
1270 ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
1271 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
1272 #endif
1273 {
1274 	struct ieee80211com *ic = nt->nt_ic;
1275 	struct ieee80211_node *ni;
1276 	int hash;
1277 
1278 	hash = IEEE80211_NODE_HASH(macaddr);
1279 	IEEE80211_NODE_LOCK(nt);
1280 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1281 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1282 		    ni->ni_esslen == ic->ic_des_esslen &&
1283 		    memcmp(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen) == 0) {
1284 			ieee80211_ref_node(ni);		/* mark referenced */
1285 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1286 #ifdef IEEE80211_DEBUG_REFCNT
1287 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1288 			    func, line,
1289 #else
1290 			    "%s %p<%s> refcnt %d\n", __func__,
1291 #endif
1292 			     ni, ether_sprintf(ni->ni_macaddr),
1293 			     ieee80211_node_refcnt(ni));
1294 			break;
1295 		}
1296 	}
1297 	IEEE80211_NODE_UNLOCK(nt);
1298 	return ni;
1299 }
1300 
1301 static void
1302 _ieee80211_free_node(struct ieee80211_node *ni)
1303 {
1304 	struct ieee80211com *ic = ni->ni_ic;
1305 	struct ieee80211_node_table *nt = ni->ni_table;
1306 
1307 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1308 		"%s %p<%s> in %s table\n", __func__, ni,
1309 		ether_sprintf(ni->ni_macaddr),
1310 		nt != NULL ? nt->nt_name : "<gone>");
1311 
1312 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1313 	if (nt != NULL) {
1314 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1315 		LIST_REMOVE(ni, ni_hash);
1316 	}
1317 	ic->ic_node_free(ni);
1318 }
1319 
1320 void
1321 #ifdef IEEE80211_DEBUG_REFCNT
1322 ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
1323 #else
1324 ieee80211_free_node(struct ieee80211_node *ni)
1325 #endif
1326 {
1327 	struct ieee80211_node_table *nt = ni->ni_table;
1328 
1329 #ifdef IEEE80211_DEBUG_REFCNT
1330 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1331 		"%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line, ni,
1332 		 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
1333 #endif
1334 	if (ieee80211_node_dectestref(ni)) {
1335 		/*
1336 		 * Beware; if the node is marked gone then it's already
1337 		 * been removed from the table and we cannot assume the
1338 		 * table still exists.  Regardless, there's no need to lock
1339 		 * the table.
1340 		 */
1341 		if (ni->ni_table != NULL) {
1342 			IEEE80211_NODE_LOCK(nt);
1343 			_ieee80211_free_node(ni);
1344 			IEEE80211_NODE_UNLOCK(nt);
1345 		} else
1346 			_ieee80211_free_node(ni);
1347 	}
1348 }
1349 
1350 /*
1351  * Reclaim a node.  If this is the last reference count then
1352  * do the normal free work.  Otherwise remove it from the node
1353  * table and mark it gone by clearing the back-reference.
1354  */
1355 static void
1356 node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1357 {
1358 
1359 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1360 		"%s: remove %p<%s> from %s table, refcnt %d\n",
1361 		__func__, ni, ether_sprintf(ni->ni_macaddr),
1362 		nt->nt_name, ieee80211_node_refcnt(ni)-1);
1363 	if (!ieee80211_node_dectestref(ni)) {
1364 		/*
1365 		 * Other references are present, just remove the
1366 		 * node from the table so it cannot be found.  When
1367 		 * the references are dropped storage will be
1368 		 * reclaimed.
1369 		 */
1370 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1371 		LIST_REMOVE(ni, ni_hash);
1372 		ni->ni_table = NULL;		/* clear reference */
1373 	} else
1374 		_ieee80211_free_node(ni);
1375 }
1376 
1377 static void
1378 ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
1379 {
1380 	struct ieee80211com *ic = nt->nt_ic;
1381 	struct ieee80211_node *ni;
1382 
1383 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1384 		"%s: free all nodes in %s table\n", __func__, nt->nt_name);
1385 
1386 	while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
1387 		if (ni->ni_associd != 0) {
1388 			if (ic->ic_auth->ia_node_leave != NULL)
1389 				ic->ic_auth->ia_node_leave(ic, ni);
1390 			IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1391 		}
1392 		node_reclaim(nt, ni);
1393 	}
1394 	ieee80211_reset_erp(ic);
1395 }
1396 
1397 static void
1398 ieee80211_free_allnodes(struct ieee80211_node_table *nt)
1399 {
1400 
1401 	IEEE80211_NODE_LOCK(nt);
1402 	ieee80211_free_allnodes_locked(nt);
1403 	IEEE80211_NODE_UNLOCK(nt);
1404 }
1405 
1406 /*
1407  * Timeout entries in the scan cache.
1408  */
1409 static void
1410 ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
1411 {
1412 	struct ieee80211com *ic = nt->nt_ic;
1413 	struct ieee80211_node *ni, *tni;
1414 
1415 	IEEE80211_NODE_LOCK(nt);
1416 	ni = ic->ic_bss;
1417 	/* XXX belongs elsewhere */
1418 	if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
1419 		m_freem(ni->ni_rxfrag[0]);
1420 		ni->ni_rxfrag[0] = NULL;
1421 	}
1422 	TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
1423 		if (ni->ni_inact && --ni->ni_inact == 0) {
1424 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1425 			    "[%s] scan candidate purged from cache "
1426 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1427 			    ieee80211_node_refcnt(ni));
1428 			node_reclaim(nt, ni);
1429 		}
1430 	}
1431 	IEEE80211_NODE_UNLOCK(nt);
1432 
1433 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1434 }
1435 
1436 /*
1437  * Timeout inactive stations and do related housekeeping.
1438  * Note that we cannot hold the node lock while sending a
1439  * frame as this would lead to a LOR.  Instead we use a
1440  * generation number to mark nodes that we've scanned and
1441  * drop the lock and restart a scan if we have to time out
1442  * a node.  Since we are single-threaded by virtue of
1443  * controlling the inactivity timer we can be sure this will
1444  * process each node only once.
1445  */
1446 static void
1447 ieee80211_timeout_stations(struct ieee80211_node_table *nt)
1448 {
1449 	struct ieee80211com *ic = nt->nt_ic;
1450 	struct ieee80211_node *ni;
1451 	u_int gen;
1452 
1453 	IEEE80211_SCAN_LOCK(nt);
1454 	gen = nt->nt_scangen++;
1455 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1456 		"%s: %s scangen %u\n", __func__, nt->nt_name, gen);
1457 restart:
1458 	IEEE80211_NODE_LOCK(nt);
1459 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1460 		if (ni->ni_scangen == gen)	/* previously handled */
1461 			continue;
1462 		ni->ni_scangen = gen;
1463 		/*
1464 		 * Free fragment if not needed anymore
1465 		 * (last fragment older than 1s).
1466 		 * XXX doesn't belong here
1467 		 */
1468 		if (ni->ni_rxfrag[0] != NULL &&
1469 		    ticks > ni->ni_rxfragstamp + hz) {
1470 			m_freem(ni->ni_rxfrag[0]);
1471 			ni->ni_rxfrag[0] = NULL;
1472 		}
1473 		/*
1474 		 * Special case ourself; we may be idle for extended periods
1475 		 * of time and regardless reclaiming our state is wrong.
1476 		 */
1477 		if (ni == ic->ic_bss)
1478 			continue;
1479 		ni->ni_inact--;
1480 		if (ni->ni_associd != 0) {
1481 			/*
1482 			 * Age frames on the power save queue. The
1483 			 * aging interval is 4 times the listen
1484 			 * interval specified by the station.  This
1485 			 * number is factored into the age calculations
1486 			 * when the frame is placed on the queue.  We
1487 			 * store ages as time differences we can check
1488 			 * and/or adjust only the head of the list.
1489 			 */
1490 			if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
1491 				struct mbuf *m;
1492 				int discard = 0;
1493 
1494 				IEEE80211_NODE_SAVEQ_LOCK(ni);
1495 				while (IF_POLL(&ni->ni_savedq, m) != NULL &&
1496 				     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
1497 IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
1498 					_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
1499 					m_freem(m);
1500 					discard++;
1501 				}
1502 				if (m != NULL)
1503 					M_AGE_SUB(m, IEEE80211_INACT_WAIT);
1504 				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1505 
1506 				if (discard != 0) {
1507 					IEEE80211_DPRINTF(ic,
1508 					    IEEE80211_MSG_POWER,
1509 					    "[%s] discard %u frames for age\n",
1510 					    ether_sprintf(ni->ni_macaddr),
1511 					    discard);
1512 					IEEE80211_NODE_STAT_ADD(ni,
1513 						ps_discard, discard);
1514 					if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
1515 						ic->ic_set_tim(ic, ni, 0);
1516 				}
1517 			}
1518 			/*
1519 			 * Probe the station before time it out.  We
1520 			 * send a null data frame which may not be
1521 			 * universally supported by drivers (need it
1522 			 * for ps-poll support so it should be...).
1523 			 */
1524 			if (0 < ni->ni_inact &&
1525 			    ni->ni_inact <= ic->ic_inact_probe) {
1526 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1527 				    "[%s] probe station due to inactivity\n",
1528 				    ether_sprintf(ni->ni_macaddr));
1529 				IEEE80211_NODE_UNLOCK(nt);
1530 				ieee80211_send_nulldata(ic, ni);
1531 				/* XXX stat? */
1532 				goto restart;
1533 			}
1534 		}
1535 		if (ni->ni_inact <= 0) {
1536 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1537 			    "[%s] station timed out due to inactivity "
1538 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1539 			    ieee80211_node_refcnt(ni));
1540 			/*
1541 			 * Send a deauthenticate frame and drop the station.
1542 			 * This is somewhat complicated due to reference counts
1543 			 * and locking.  At this point a station will typically
1544 			 * have a reference count of 1.  ieee80211_node_leave
1545 			 * will do a "free" of the node which will drop the
1546 			 * reference count.  But in the meantime a reference
1547 			 * wil be held by the deauth frame.  The actual reclaim
1548 			 * of the node will happen either after the tx is
1549 			 * completed or by ieee80211_node_leave.
1550 			 *
1551 			 * Separately we must drop the node lock before sending
1552 			 * in case the driver takes a lock, as this will result
1553 			 * in  LOR between the node lock and the driver lock.
1554 			 */
1555 			IEEE80211_NODE_UNLOCK(nt);
1556 			if (ni->ni_associd != 0) {
1557 				IEEE80211_SEND_MGMT(ic, ni,
1558 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
1559 				    IEEE80211_REASON_AUTH_EXPIRE);
1560 			}
1561 			ieee80211_node_leave(ic, ni);
1562 			ic->ic_stats.is_node_timeout++;
1563 			goto restart;
1564 		}
1565 	}
1566 	IEEE80211_NODE_UNLOCK(nt);
1567 
1568 	IEEE80211_SCAN_UNLOCK(nt);
1569 
1570 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1571 }
1572 
1573 void
1574 ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
1575 {
1576 	struct ieee80211_node *ni;
1577 	u_int gen;
1578 
1579 	IEEE80211_SCAN_LOCK(nt);
1580 	gen = nt->nt_scangen++;
1581 restart:
1582 	IEEE80211_NODE_LOCK(nt);
1583 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1584 		if (ni->ni_scangen != gen) {
1585 			ni->ni_scangen = gen;
1586 			(void) ieee80211_ref_node(ni);
1587 			IEEE80211_NODE_UNLOCK(nt);
1588 			(*f)(arg, ni);
1589 			ieee80211_free_node(ni);
1590 			goto restart;
1591 		}
1592 	}
1593 	IEEE80211_NODE_UNLOCK(nt);
1594 
1595 	IEEE80211_SCAN_UNLOCK(nt);
1596 }
1597 
1598 void
1599 ieee80211_dump_node(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1600 {
1601 	printf("0x%p: mac %s refcnt %d\n", ni,
1602 		ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
1603 	printf("\tscangen %u authmode %u flags 0x%x\n",
1604 		ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
1605 	printf("\tassocid 0x%x txpower %u vlan %u\n",
1606 		ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
1607 	printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
1608 		ni->ni_txseqs[0],
1609 		ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
1610 		ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
1611 		ni->ni_rxfragstamp);
1612 	printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
1613 		ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
1614 	printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
1615 		ether_sprintf(ni->ni_bssid),
1616 		ni->ni_esslen, ni->ni_essid,
1617 		ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
1618 	printf("\tfails %u inact %u txrate %u\n",
1619 		ni->ni_fails, ni->ni_inact, ni->ni_txrate);
1620 }
1621 
1622 void
1623 ieee80211_dump_nodes(struct ieee80211_node_table *nt)
1624 {
1625 	ieee80211_iterate_nodes(nt,
1626 		(ieee80211_iter_func *) ieee80211_dump_node, nt);
1627 }
1628 
1629 /*
1630  * Handle a station joining an 11g network.
1631  */
1632 static void
1633 ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1634 {
1635 
1636 	/*
1637 	 * Station isn't capable of short slot time.  Bump
1638 	 * the count of long slot time stations and disable
1639 	 * use of short slot time.  Note that the actual switch
1640 	 * over to long slot time use may not occur until the
1641 	 * next beacon transmission (per sec. 7.3.1.4 of 11g).
1642 	 */
1643 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1644 		ic->ic_longslotsta++;
1645 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1646 		    "[%s] station needs long slot time, count %d\n",
1647 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1648 		/* XXX vap's w/ conflicting needs won't work */
1649 		ieee80211_set_shortslottime(ic, 0);
1650 	}
1651 	/*
1652 	 * If the new station is not an ERP station
1653 	 * then bump the counter and enable protection
1654 	 * if configured.
1655 	 */
1656 	if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
1657 		ic->ic_nonerpsta++;
1658 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1659 		    "[%s] station is !ERP, %d non-ERP stations associated\n",
1660 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1661 		/*
1662 		 * If protection is configured, enable it.
1663 		 */
1664 		if (ic->ic_protmode != IEEE80211_PROT_NONE) {
1665 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1666 			    "%s: enable use of protection\n", __func__);
1667 			ic->ic_flags |= IEEE80211_F_USEPROT;
1668 		}
1669 		/*
1670 		 * If station does not support short preamble
1671 		 * then we must enable use of Barker preamble.
1672 		 */
1673 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
1674 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1675 			    "[%s] station needs long preamble\n",
1676 			    ether_sprintf(ni->ni_macaddr));
1677 			ic->ic_flags |= IEEE80211_F_USEBARKER;
1678 			ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
1679 		}
1680 	} else
1681 		ni->ni_flags |= IEEE80211_NODE_ERP;
1682 }
1683 
1684 void
1685 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
1686 {
1687 	int newassoc;
1688 
1689 	if (ni->ni_associd == 0) {
1690 		u_int16_t aid;
1691 
1692 		/*
1693 		 * It would be good to search the bitmap
1694 		 * more efficiently, but this will do for now.
1695 		 */
1696 		for (aid = 1; aid < ic->ic_max_aid; aid++) {
1697 			if (!IEEE80211_AID_ISSET(aid,
1698 			    ic->ic_aid_bitmap))
1699 				break;
1700 		}
1701 		if (aid >= ic->ic_max_aid) {
1702 			IEEE80211_SEND_MGMT(ic, ni, resp,
1703 			    IEEE80211_REASON_ASSOC_TOOMANY);
1704 			ieee80211_node_leave(ic, ni);
1705 			return;
1706 		}
1707 		ni->ni_associd = aid | 0xc000;
1708 		IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
1709 		ic->ic_sta_assoc++;
1710 		newassoc = 1;
1711 		if (ic->ic_curmode == IEEE80211_MODE_11G ||
1712 		    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1713 			ieee80211_node_join_11g(ic, ni);
1714 	} else
1715 		newassoc = 0;
1716 
1717 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1718 	    "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
1719 	    ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
1720 	    IEEE80211_NODE_AID(ni),
1721 	    ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
1722 	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
1723 	    ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
1724 	    ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
1725 	);
1726 
1727 	/* give driver a chance to setup state like ni_txrate */
1728 	if (ic->ic_newassoc != NULL)
1729 		ic->ic_newassoc(ic, ni, newassoc);
1730 	ni->ni_inact_reload = ic->ic_inact_auth;
1731 	ni->ni_inact = ni->ni_inact_reload;
1732 	IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
1733 	/* tell the authenticator about new station */
1734 	if (ic->ic_auth->ia_node_join != NULL)
1735 		ic->ic_auth->ia_node_join(ic, ni);
1736 	ieee80211_notify_node_join(ic, ni, newassoc);
1737 }
1738 
1739 /*
1740  * Handle a station leaving an 11g network.
1741  */
1742 static void
1743 ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1744 {
1745 
1746 	IASSERT(ic->ic_curmode == IEEE80211_MODE_11G ||
1747 		ic->ic_curmode == IEEE80211_MODE_TURBO_G,
1748 		("not in 11g, curmode %x", ic->ic_curmode));
1749 
1750 	/*
1751 	 * If a long slot station do the slot time bookkeeping.
1752 	 */
1753 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1754 		IASSERT(ic->ic_longslotsta > 0,
1755 		    ("bogus long slot station count %d", ic->ic_longslotsta));
1756 		ic->ic_longslotsta--;
1757 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1758 		    "[%s] long slot time station leaves, count now %d\n",
1759 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1760 		if (ic->ic_longslotsta == 0) {
1761 			/*
1762 			 * Re-enable use of short slot time if supported
1763 			 * and not operating in IBSS mode (per spec).
1764 			 */
1765 			if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
1766 			    ic->ic_opmode != IEEE80211_M_IBSS) {
1767 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1768 				    "%s: re-enable use of short slot time\n",
1769 				    __func__);
1770 				ieee80211_set_shortslottime(ic, 1);
1771 			}
1772 		}
1773 	}
1774 	/*
1775 	 * If a non-ERP station do the protection-related bookkeeping.
1776 	 */
1777 	if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
1778 		IASSERT(ic->ic_nonerpsta > 0,
1779 		    ("bogus non-ERP station count %d", ic->ic_nonerpsta));
1780 		ic->ic_nonerpsta--;
1781 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1782 		    "[%s] non-ERP station leaves, count now %d\n",
1783 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1784 		if (ic->ic_nonerpsta == 0) {
1785 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1786 				"%s: disable use of protection\n", __func__);
1787 			ic->ic_flags &= ~IEEE80211_F_USEPROT;
1788 			/* XXX verify mode? */
1789 			if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
1790 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1791 				    "%s: re-enable use of short preamble\n",
1792 				    __func__);
1793 				ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
1794 				ic->ic_flags &= ~IEEE80211_F_USEBARKER;
1795 			}
1796 		}
1797 	}
1798 }
1799 
1800 /*
1801  * Handle bookkeeping for station deauthentication/disassociation
1802  * when operating as an ap.
1803  */
1804 void
1805 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
1806 {
1807 	struct ieee80211_node_table *nt = ni->ni_table;
1808 
1809 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1810 	    "[%s] station with aid %d leaves\n",
1811 	    ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
1812 
1813 	IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1814 		ic->ic_opmode == IEEE80211_M_IBSS ||
1815 		ic->ic_opmode == IEEE80211_M_AHDEMO,
1816 		("unexpected operating mode %u", ic->ic_opmode));
1817 	/*
1818 	 * If node wasn't previously associated all
1819 	 * we need to do is reclaim the reference.
1820 	 */
1821 	/* XXX ibss mode bypasses 11g and notification */
1822 	if (ni->ni_associd == 0)
1823 		goto done;
1824 	/*
1825 	 * Tell the authenticator the station is leaving.
1826 	 * Note that we must do this before yanking the
1827 	 * association id as the authenticator uses the
1828 	 * associd to locate it's state block.
1829 	 */
1830 	if (ic->ic_auth->ia_node_leave != NULL)
1831 		ic->ic_auth->ia_node_leave(ic, ni);
1832 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1833 	ni->ni_associd = 0;
1834 	ic->ic_sta_assoc--;
1835 
1836 	if (ic->ic_curmode == IEEE80211_MODE_11G ||
1837 	    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1838 		ieee80211_node_leave_11g(ic, ni);
1839 	/*
1840 	 * Cleanup station state.  In particular clear various
1841 	 * state that might otherwise be reused if the node
1842 	 * is reused before the reference count goes to zero
1843 	 * (and memory is reclaimed).
1844 	 */
1845 	ieee80211_sta_leave(ic, ni);
1846 done:
1847 	/*
1848 	 * Remove the node from any table it's recorded in and
1849 	 * drop the caller's reference.  Removal from the table
1850 	 * is important to insure the node is not reprocessed
1851 	 * for inactivity.
1852 	 */
1853 	if (nt != NULL) {
1854 		IEEE80211_NODE_LOCK(nt);
1855 		node_reclaim(nt, ni);
1856 		IEEE80211_NODE_UNLOCK(nt);
1857 	} else
1858 		ieee80211_free_node(ni);
1859 }
1860 
1861 u_int8_t
1862 ieee80211_getrssi(struct ieee80211com *ic)
1863 {
1864 #define	NZ(x)	((x) == 0 ? 1 : (x))
1865 	struct ieee80211_node_table *nt = &ic->ic_sta;
1866 	u_int32_t rssi_samples, rssi_total;
1867 	struct ieee80211_node *ni;
1868 
1869 	rssi_total = 0;
1870 	rssi_samples = 0;
1871 	switch (ic->ic_opmode) {
1872 	case IEEE80211_M_IBSS:		/* average of all ibss neighbors */
1873 		/* XXX locking */
1874 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
1875 			if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
1876 				rssi_samples++;
1877 				rssi_total += ic->ic_node_getrssi(ni);
1878 			}
1879 		break;
1880 	case IEEE80211_M_AHDEMO:	/* average of all neighbors */
1881 		/* XXX locking */
1882 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1883 			rssi_samples++;
1884 			rssi_total += ic->ic_node_getrssi(ni);
1885 		}
1886 		break;
1887 	case IEEE80211_M_HOSTAP:	/* average of all associated stations */
1888 #ifndef IEEE80211_NO_HOSTAP
1889 		/* XXX locking */
1890 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
1891 			if (IEEE80211_AID(ni->ni_associd) != 0) {
1892 				rssi_samples++;
1893 				rssi_total += ic->ic_node_getrssi(ni);
1894 			}
1895 #endif /* !IEEE80211_NO_HOSTAP */
1896 		break;
1897 	case IEEE80211_M_MONITOR:	/* XXX */
1898 	case IEEE80211_M_STA:		/* use stats from associated ap */
1899 	default:
1900 		if (ic->ic_bss != NULL)
1901 			rssi_total = ic->ic_node_getrssi(ic->ic_bss);
1902 		rssi_samples = 1;
1903 		break;
1904 	}
1905 	return rssi_total / NZ(rssi_samples);
1906 #undef NZ
1907 }
1908 
1909 /*
1910  * Indicate whether there are frames queued for a station in power-save mode.
1911  */
1912 static void
1913 ieee80211_set_tim(struct ieee80211com *ic, struct ieee80211_node *ni, int set)
1914 {
1915 	u_int16_t aid;
1916 
1917 	IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1918 		ic->ic_opmode == IEEE80211_M_IBSS,
1919 		("operating mode %u", ic->ic_opmode));
1920 
1921 	aid = IEEE80211_AID(ni->ni_associd);
1922 	IASSERT(aid < ic->ic_max_aid,
1923 		("bogus aid %u, max %u", aid, ic->ic_max_aid));
1924 
1925 	IEEE80211_BEACON_LOCK(ic);
1926 	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
1927 		if (set) {
1928 			setbit(ic->ic_tim_bitmap, aid);
1929 			ic->ic_ps_pending++;
1930 		} else {
1931 			clrbit(ic->ic_tim_bitmap, aid);
1932 			ic->ic_ps_pending--;
1933 		}
1934 		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
1935 	}
1936 	IEEE80211_BEACON_UNLOCK(ic);
1937 }
1938 
1939 /*
1940  * Node table support.
1941  */
1942 
1943 static void
1944 ieee80211_node_table_init(struct ieee80211com *ic,
1945 	struct ieee80211_node_table *nt,
1946 	const char *name, int inact,
1947 	void (*timeout)(struct ieee80211_node_table *))
1948 {
1949 
1950 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1951 		"%s %s table, inact %u\n", __func__, name, inact);
1952 
1953 	nt->nt_ic = ic;
1954 	/* XXX need unit */
1955 	IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1956 	IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1957 	TAILQ_INIT(&nt->nt_node);
1958 	nt->nt_name = name;
1959 	nt->nt_scangen = 1;
1960 	nt->nt_inact_init = inact;
1961 	nt->nt_timeout = timeout;
1962 }
1963 
1964 void
1965 ieee80211_node_table_reset(struct ieee80211_node_table *nt)
1966 {
1967 
1968 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1969 		"%s %s table\n", __func__, nt->nt_name);
1970 
1971 	IEEE80211_NODE_LOCK(nt);
1972 	nt->nt_inact_timer = 0;
1973 	ieee80211_free_allnodes_locked(nt);
1974 	IEEE80211_NODE_UNLOCK(nt);
1975 }
1976 
1977 static void
1978 ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
1979 {
1980 
1981 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1982 		"%s %s table\n", __func__, nt->nt_name);
1983 
1984 	ieee80211_free_allnodes_locked(nt);
1985 	IEEE80211_SCAN_LOCK_DESTROY(nt);
1986 	IEEE80211_NODE_LOCK_DESTROY(nt);
1987 }
1988