xref: /titanic_41/usr/src/uts/common/io/net80211/net80211_node.c (revision 058561cbaa119a6f2659bc27ef343e1b47266bb2)
1 /*
2  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Copyright (c) 2001 Atsushi Onoe
8  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * Alternatively, this software may be distributed under the terms of the
23  * GNU General Public License ("GPL") version 2 as published by the Free
24  * Software Foundation.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #pragma ident	"%Z%%M%	%I%	%E% SMI"
39 
40 /*
41  * Node management routines
42  */
43 
44 #include "net80211_impl.h"
45 
46 static ieee80211_node_t *ieee80211_node_alloc(ieee80211com_t *);
47 static void ieee80211_node_cleanup(ieee80211_node_t *);
48 static void ieee80211_node_free(ieee80211_node_t *);
49 static uint8_t ieee80211_node_getrssi(const ieee80211_node_t *);
50 static void ieee80211_setup_node(ieee80211com_t *, ieee80211_node_table_t *,
51     ieee80211_node_t *, const uint8_t *);
52 static void ieee80211_node_reclaim(ieee80211_node_table_t *,
53     ieee80211_node_t *);
54 static void ieee80211_free_node_locked(ieee80211_node_t *);
55 static void ieee80211_free_allnodes(ieee80211_node_table_t *);
56 static void ieee80211_node_leave(ieee80211com_t *, ieee80211_node_t *);
57 static void ieee80211_timeout_scan_candidates(ieee80211_node_table_t *);
58 static void ieee80211_timeout_stations(ieee80211_node_table_t *);
59 static void ieee80211_node_table_init(ieee80211com_t *,
60     ieee80211_node_table_t *, const char *, int, int,
61     void (*timeout)(ieee80211_node_table_t *));
62 static void ieee80211_node_table_cleanup(ieee80211_node_table_t *);
63 
64 /*
65  * association failures before ignored
66  * The failure may be caused by the response frame is lost for
67  * environmental reason. So Try associate more than once before
68  * ignore the node
69  */
70 #define	IEEE80211_STA_FAILS_MAX	2
71 
72 /*
73  * Initialize node database management callbacks for the interface.
74  * This function is called by ieee80211_attach(). These callback
75  * functions may be overridden in special circumstances, as long as
76  * as this is done after calling ieee80211_attach() and prior to any
77  * other call which may allocate a node
78  */
79 void
80 ieee80211_node_attach(ieee80211com_t *ic)
81 {
82 	struct ieee80211_impl *im = ic->ic_private;
83 
84 	ic->ic_node_alloc = ieee80211_node_alloc;
85 	ic->ic_node_free = ieee80211_node_free;
86 	ic->ic_node_cleanup = ieee80211_node_cleanup;
87 	ic->ic_node_getrssi = ieee80211_node_getrssi;
88 
89 	/* default station inactivity timer setings */
90 	im->im_inact_init = IEEE80211_INACT_INIT;
91 	im->im_inact_assoc = IEEE80211_INACT_ASSOC;
92 	im->im_inact_run = IEEE80211_INACT_RUN;
93 	im->im_inact_probe = IEEE80211_INACT_PROBE;
94 }
95 
96 /*
97  * Initialize node databases and the ic_bss node element.
98  */
99 void
100 ieee80211_node_lateattach(ieee80211com_t *ic)
101 {
102 	/*
103 	 * Calculate ic_tim_bitmap size in bytes
104 	 * IEEE80211_AID_MAX defines maximum bits in ic_tim_bitmap
105 	 */
106 	ic->ic_tim_len = howmany(IEEE80211_AID_MAX, 8) * sizeof (uint8_t);
107 
108 	ieee80211_node_table_init(ic, &ic->ic_sta, "station",
109 		IEEE80211_INACT_INIT, IEEE80211_WEP_NKID,
110 		ieee80211_timeout_stations);
111 	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
112 		IEEE80211_INACT_SCAN, 0, ieee80211_timeout_scan_candidates);
113 
114 	ieee80211_reset_bss(ic);
115 }
116 
117 /*
118  * Destroy all node databases and is usually called during device detach
119  */
120 void
121 ieee80211_node_detach(ieee80211com_t *ic)
122 {
123 	/* Node Detach */
124 	if (ic->ic_bss != NULL) {
125 		ieee80211_free_node(ic->ic_bss);
126 		ic->ic_bss = NULL;
127 	}
128 	ieee80211_node_table_cleanup(&ic->ic_scan);
129 	ieee80211_node_table_cleanup(&ic->ic_sta);
130 }
131 
132 /*
133  * Increase a node's reference count
134  *
135  * Return pointer to the node
136  */
137 ieee80211_node_t *
138 ieee80211_ref_node(ieee80211_node_t *in)
139 {
140 	ieee80211_node_incref(in);
141 	return (in);
142 }
143 
144 /*
145  * Dexrease a node's reference count
146  */
147 void
148 ieee80211_unref_node(ieee80211_node_t **in)
149 {
150 	ieee80211_node_decref(*in);
151 	*in = NULL;			/* guard against use */
152 }
153 
154 /*
155  * Mark ports authorized for data traffic. This function is usually
156  * used by 802.1x authenticator.
157  */
158 void
159 ieee80211_node_authorize(ieee80211_node_t *in)
160 {
161 	ieee80211_impl_t *im = in->in_ic->ic_private;
162 
163 	in->in_flags |= IEEE80211_NODE_AUTH;
164 	in->in_inact_reload = im->im_inact_run;
165 }
166 
167 /*
168  * Mark ports unauthorized for data traffic. This function is usually
169  * used by 802.1x authenticator.
170  */
171 void
172 ieee80211_node_unauthorize(ieee80211_node_t *in)
173 {
174 	in->in_flags &= ~IEEE80211_NODE_AUTH;
175 }
176 
177 /*
178  * Set/change the channel.  The rate set is also updated as
179  * to insure a consistent view by drivers.
180  */
181 static void
182 ieee80211_node_setchan(ieee80211com_t *ic, ieee80211_node_t *in,
183     struct ieee80211_channel *chan)
184 {
185 	if (chan == IEEE80211_CHAN_ANYC)
186 		chan = ic->ic_curchan;
187 	in->in_chan = chan;
188 	in->in_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
189 }
190 
191 /*
192  * Initialize the channel set to scan based on the available channels
193  * and the current PHY mode.
194  */
195 static void
196 ieee80211_reset_scan(ieee80211com_t *ic)
197 {
198 	ieee80211_impl_t	*im = ic->ic_private;
199 
200 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
201 		(void) memset(im->im_chan_scan, 0, sizeof (im->im_chan_scan));
202 		ieee80211_setbit(im->im_chan_scan,
203 			ieee80211_chan2ieee(ic, ic->ic_des_chan));
204 	} else {
205 		bcopy(ic->ic_chan_active, im->im_chan_scan,
206 			sizeof (ic->ic_chan_active));
207 	}
208 	ieee80211_dbg(IEEE80211_MSG_SCAN, "ieee80211_reset_scan(): "
209 		"start chan %u\n", ieee80211_chan2ieee(ic, ic->ic_curchan));
210 }
211 
212 /*
213  * Begin an active scan. Initialize the node cache. The scan
214  * begins on the next radio channel by calling ieee80211_next_scan().
215  * The actual scanning is not automated. The driver itself
216  * only handles setting the radio frequency and stepping through
217  * the channels.
218  */
219 void
220 ieee80211_begin_scan(ieee80211com_t *ic, boolean_t reset)
221 {
222 	IEEE80211_LOCK(ic);
223 
224 	if (ic->ic_opmode != IEEE80211_M_HOSTAP)
225 		ic->ic_flags |= IEEE80211_F_ASCAN;
226 	ieee80211_dbg(IEEE80211_MSG_SCAN,
227 		"begin %s scan in %s mode on channel %u\n",
228 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
229 		ieee80211_phymode_name[ic->ic_curmode],
230 		ieee80211_chan2ieee(ic, ic->ic_curchan));
231 
232 	/*
233 	 * Clear scan state and flush any previously seen AP's.
234 	 */
235 	ieee80211_reset_scan(ic);
236 	if (reset)
237 		ieee80211_free_allnodes(&ic->ic_scan);
238 
239 	ic->ic_flags |= IEEE80211_F_SCAN;
240 	IEEE80211_UNLOCK(ic);
241 
242 	/* Scan the next channel. */
243 	ieee80211_next_scan(ic);
244 }
245 
246 /*
247  * Switch to the next channel marked for scanning.
248  * A driver is expected to first call ieee80211_begin_scan(),
249  * to initialize the node cache, then set the radio channel
250  * on the device. And then after a certain time has elapsed,
251  * call ieee80211_next_scan() to move to the next channel.
252  * Typically, a timeout routine is used to automate this process.
253  */
254 void
255 ieee80211_next_scan(ieee80211com_t *ic)
256 {
257 	ieee80211_impl_t *im = ic->ic_private;
258 	struct ieee80211_channel *chan;
259 
260 	IEEE80211_LOCK(ic);
261 	/*
262 	 * Insure any previous mgt frame timeouts don't fire.
263 	 * This assumes the driver does the right thing in
264 	 * flushing anything queued in the driver and below.
265 	 */
266 	im->im_mgt_timer = 0;
267 
268 	chan = ic->ic_curchan;
269 	do {
270 		if (++chan > &ic->ic_sup_channels[IEEE80211_CHAN_MAX])
271 			chan = &ic->ic_sup_channels[0];
272 		if (ieee80211_isset(im->im_chan_scan,
273 		    ieee80211_chan2ieee(ic, chan))) {
274 			ieee80211_clrbit(im->im_chan_scan,
275 				ieee80211_chan2ieee(ic, chan));
276 			ieee80211_dbg(IEEE80211_MSG_SCAN,
277 				"ieee80211_next_scan: chan %d->%d\n",
278 				ieee80211_chan2ieee(ic, ic->ic_curchan),
279 				ieee80211_chan2ieee(ic, chan));
280 			ic->ic_curchan = chan;
281 			/*
282 			 * drivers should do this as needed,
283 			 * for now maintain compatibility
284 			 */
285 			ic->ic_bss->in_rates =
286 				ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
287 			IEEE80211_UNLOCK(ic);
288 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
289 			return;
290 		}
291 	} while (chan != ic->ic_curchan);
292 	IEEE80211_UNLOCK(ic);
293 	ieee80211_end_scan(ic);
294 }
295 
296 /*
297  * Copy useful state from node obss into nbss.
298  */
299 static void
300 ieee80211_copy_bss(ieee80211_node_t *nbss, const ieee80211_node_t *obss)
301 {
302 	/* propagate useful state */
303 	nbss->in_authmode = obss->in_authmode;
304 	nbss->in_txpower = obss->in_txpower;
305 	nbss->in_vlan = obss->in_vlan;
306 }
307 
308 /*
309  * Setup the net80211 specific portion of an interface's softc, ic,
310  * for use in IBSS mode
311  */
312 void
313 ieee80211_create_ibss(ieee80211com_t *ic, struct ieee80211_channel *chan)
314 {
315 	ieee80211_impl_t *im = ic->ic_private;
316 	ieee80211_node_table_t *nt;
317 	ieee80211_node_t *in;
318 
319 	IEEE80211_LOCK_ASSERT(ic);
320 	ieee80211_dbg(IEEE80211_MSG_SCAN, "ieee80211_create_ibss: "
321 		"creating ibss\n");
322 
323 	/*
324 	 * Create the station/neighbor table.  Note that for adhoc
325 	 * mode we make the initial inactivity timer longer since
326 	 * we create nodes only through discovery and they typically
327 	 * are long-lived associations.
328 	 */
329 	nt = &ic->ic_sta;
330 	IEEE80211_NODE_LOCK(nt);
331 	nt->nt_name = "neighbor";
332 	nt->nt_inact_init = im->im_inact_run;
333 	IEEE80211_NODE_UNLOCK(nt);
334 
335 	in = ieee80211_alloc_node(ic, &ic->ic_sta, ic->ic_macaddr);
336 	if (in == NULL) {
337 		ieee80211_err("ieee80211_create_ibss(): alloc node failed\n");
338 		return;
339 	}
340 	IEEE80211_ADDR_COPY(in->in_bssid, ic->ic_macaddr);
341 	in->in_esslen = ic->ic_des_esslen;
342 	(void) memcpy(in->in_essid, ic->ic_des_essid, in->in_esslen);
343 	ieee80211_copy_bss(in, ic->ic_bss);
344 	in->in_intval = ic->ic_bintval;
345 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
346 		in->in_capinfo |= IEEE80211_CAPINFO_PRIVACY;
347 	if (ic->ic_phytype == IEEE80211_T_FH) {
348 		in->in_fhdwell = 200;
349 		in->in_fhindex = 1;
350 	}
351 	switch (ic->ic_opmode) {
352 	case IEEE80211_M_IBSS:
353 		ic->ic_flags |= IEEE80211_F_SIBSS;
354 		in->in_capinfo |= IEEE80211_CAPINFO_IBSS;
355 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
356 			IEEE80211_ADDR_COPY(in->in_bssid, ic->ic_des_bssid);
357 		else
358 			in->in_bssid[0] |= 0x02;	/* local bit for IBSS */
359 		break;
360 	case IEEE80211_M_AHDEMO:
361 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
362 			IEEE80211_ADDR_COPY(in->in_bssid, ic->ic_des_bssid);
363 		else
364 			(void) memset(in->in_bssid, 0, IEEE80211_ADDR_LEN);
365 		break;
366 	default:
367 		ieee80211_err("ieee80211_create_ibss(): "
368 			"wrong opmode %u to creat IBSS, abort\n",
369 			ic->ic_opmode);
370 		ieee80211_free_node(in);
371 		return;
372 	}
373 
374 	/*
375 	 * Fix the channel and related attributes.
376 	 */
377 	ieee80211_node_setchan(ic, in, chan);
378 	ic->ic_curchan = chan;
379 	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
380 	/*
381 	 * Do mode-specific rate setup.
382 	 */
383 	ieee80211_setbasicrates(&in->in_rates, ic->ic_curmode);
384 	IEEE80211_UNLOCK(ic);
385 	ieee80211_sta_join(ic, in);
386 	IEEE80211_LOCK(ic);
387 }
388 
389 void
390 ieee80211_reset_bss(ieee80211com_t *ic)
391 {
392 	ieee80211_node_t *in;
393 	ieee80211_node_t *obss;
394 
395 	in = ieee80211_alloc_node(ic, &ic->ic_scan, ic->ic_macaddr);
396 	ASSERT(in != NULL);
397 	obss = ic->ic_bss;
398 	ic->ic_bss = ieee80211_ref_node(in);
399 	if (obss != NULL) {
400 		ieee80211_copy_bss(in, obss);
401 		in->in_intval = ic->ic_bintval;
402 		ieee80211_free_node(obss);
403 	}
404 }
405 
406 static int
407 ieee80211_match_bss(ieee80211com_t *ic, ieee80211_node_t *in)
408 {
409 	uint8_t rate;
410 	int fail;
411 
412 	fail = 0;
413 	if (ieee80211_isclr(ic->ic_chan_active,
414 	    ieee80211_chan2ieee(ic, in->in_chan))) {
415 		fail |= IEEE80211_BADCHAN;
416 	}
417 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
418 	    in->in_chan != ic->ic_des_chan) {
419 		fail |= IEEE80211_BADCHAN;
420 	}
421 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
422 		if (!(in->in_capinfo & IEEE80211_CAPINFO_IBSS))
423 			fail |= IEEE80211_BADOPMODE;
424 	} else {
425 		if (!(in->in_capinfo & IEEE80211_CAPINFO_ESS))
426 			fail |= IEEE80211_BADOPMODE;
427 	}
428 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
429 		if (!(in->in_capinfo & IEEE80211_CAPINFO_PRIVACY))
430 			fail |= IEEE80211_BADPRIVACY;
431 	} else {
432 		if (in->in_capinfo & IEEE80211_CAPINFO_PRIVACY)
433 			fail |= IEEE80211_BADPRIVACY;
434 	}
435 	rate = ieee80211_fix_rate(in, IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
436 	if (rate & IEEE80211_RATE_BASIC)
437 		fail |= IEEE80211_BADRATE;
438 	if (ic->ic_des_esslen != 0 &&
439 	    (in->in_esslen != ic->ic_des_esslen ||
440 	    memcmp(in->in_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0)) {
441 		fail |= IEEE80211_BADESSID;
442 	}
443 	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
444 	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, in->in_bssid)) {
445 		fail |= IEEE80211_BADBSSID;
446 	}
447 	if (in->in_fails >= IEEE80211_STA_FAILS_MAX)
448 		fail |= IEEE80211_NODEFAIL;
449 
450 	return (fail);
451 }
452 
453 #define	IEEE80211_MAXRATE(_rs) \
454 	((_rs).ir_rates[(_rs).ir_nrates - 1] & IEEE80211_RATE_VAL)
455 
456 /*
457  * Compare the capabilities of node a with node b and decide which is
458  * more desirable (return b if b is considered better than a).  Note
459  * that we assume compatibility/usability has already been checked
460  * so we don't need to (e.g. validate whether privacy is supported).
461  * Used to select the best scan candidate for association in a BSS.
462  *
463  * Return desired node
464  */
465 static ieee80211_node_t *
466 ieee80211_node_compare(ieee80211com_t *ic, ieee80211_node_t *a,
467     ieee80211_node_t *b)
468 {
469 	uint8_t maxa;
470 	uint8_t maxb;
471 	uint8_t rssia;
472 	uint8_t rssib;
473 
474 	/* privacy support preferred */
475 	if ((a->in_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
476 	    !(b->in_capinfo & IEEE80211_CAPINFO_PRIVACY)) {
477 		return (a);
478 	}
479 	if (!(a->in_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
480 	    (b->in_capinfo & IEEE80211_CAPINFO_PRIVACY)) {
481 		return (b);
482 	}
483 
484 	/* compare count of previous failures */
485 	if (b->in_fails != a->in_fails)
486 		return ((a->in_fails > b->in_fails) ? b : a);
487 
488 	rssia = ic->ic_node_getrssi(a);
489 	rssib = ic->ic_node_getrssi(b);
490 	if (ABS(rssib - rssia) < IEEE80211_RSSI_CMP_THRESHOLD) {
491 		/* best/max rate preferred if signal level close enough */
492 		maxa = IEEE80211_MAXRATE(a->in_rates);
493 		maxb = IEEE80211_MAXRATE(b->in_rates);
494 		if (maxa != maxb)
495 			return ((maxb > maxa) ? b : a);
496 		/* for now just prefer 5Ghz band to all other bands */
497 		if (IEEE80211_IS_CHAN_5GHZ(a->in_chan) &&
498 		    !IEEE80211_IS_CHAN_5GHZ(b->in_chan)) {
499 			return (a);
500 		}
501 		if (!IEEE80211_IS_CHAN_5GHZ(a->in_chan) &&
502 		    IEEE80211_IS_CHAN_5GHZ(b->in_chan)) {
503 			return (b);
504 		}
505 	}
506 	/* all things being equal, compare signal level */
507 	return ((rssib > rssia) ? b : a);
508 }
509 
510 /*
511  * Mark an ongoing scan stopped.
512  */
513 void
514 ieee80211_cancel_scan(ieee80211com_t *ic)
515 {
516 	IEEE80211_LOCK(ic);
517 	ieee80211_dbg(IEEE80211_MSG_SCAN, "ieee80211_cancel_scan()"
518 		"end %s scan\n",
519 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
520 	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
521 	cv_broadcast(&((ieee80211_impl_t *)ic->ic_private)->im_scan_cv);
522 	IEEE80211_UNLOCK(ic);
523 }
524 
525 /*
526  * Complete a scan of potential channels. It is called by
527  * ieee80211_next_scan() when the state machine has performed
528  * a full cycle of scaning on all available radio channels.
529  * ieee80211_end_scan() will inspect the node cache for suitable
530  * APs found during scaning, and associate with one, should
531  * the parameters of the node match those of the configuration
532  * requested from userland.
533  */
534 void
535 ieee80211_end_scan(ieee80211com_t *ic)
536 {
537 	ieee80211_node_table_t *nt = &ic->ic_scan;
538 	ieee80211_node_t *in;
539 	ieee80211_node_t *selbs;
540 
541 	ieee80211_cancel_scan(ic);
542 	IEEE80211_LOCK(ic);
543 
544 	/*
545 	 * Automatic sequencing; look for a candidate and
546 	 * if found join the network.
547 	 */
548 	/* NB: unlocked read should be ok */
549 	in = list_head(&nt->nt_node);
550 	if (in == NULL) {
551 		ieee80211_dbg(IEEE80211_MSG_SCAN, "ieee80211_end_scan: "
552 			"no scan candidate\n");
553 	notfound:
554 		if (ic->ic_opmode == IEEE80211_M_IBSS &&
555 		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
556 		    ic->ic_des_esslen != 0) {
557 			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
558 			IEEE80211_UNLOCK(ic);
559 			return;
560 		}
561 
562 		/*
563 		 * Reset the list of channels to scan and start again.
564 		 */
565 		ieee80211_reset_scan(ic);
566 		ic->ic_flags |= IEEE80211_F_SCAN | IEEE80211_F_ASCAN;
567 		IEEE80211_UNLOCK(ic);
568 
569 		ieee80211_next_scan(ic);
570 		return;
571 	}
572 
573 	if (ic->ic_flags & IEEE80211_F_SCANONLY) {	/* scan only */
574 		ic->ic_flags &= ~IEEE80211_F_SCANONLY;
575 		IEEE80211_UNLOCK(ic);
576 		ieee80211_new_state(ic, IEEE80211_S_INIT, -1);
577 		return;
578 	}
579 
580 	selbs = NULL;
581 	IEEE80211_NODE_LOCK(nt);
582 	while (in != NULL) {
583 		if (in->in_fails >= IEEE80211_STA_FAILS_MAX) {
584 			ieee80211_node_t *tmpin = in;
585 
586 			/*
587 			 * The configuration of the access points may change
588 			 * during my scan.  So delete the entry for the AP
589 			 * and retry to associate if there is another beacon.
590 			 */
591 			in = list_next(&nt->nt_node, tmpin);
592 			ieee80211_node_reclaim(nt, tmpin);
593 			continue;
594 		}
595 		if (ieee80211_match_bss(ic, in) == 0) {
596 			if (selbs == NULL)
597 				selbs = in;
598 			else
599 				selbs = ieee80211_node_compare(ic, selbs, in);
600 		}
601 		in = list_next(&nt->nt_node, in);
602 	}
603 	IEEE80211_NODE_UNLOCK(nt);
604 	if (selbs == NULL)
605 		goto notfound;
606 	IEEE80211_UNLOCK(ic);
607 	ieee80211_sta_join(ic, selbs);
608 }
609 
610 
611 /*
612  * Handle 802.11 ad hoc network merge.  The convention, set by the
613  * Wireless Ethernet Compatibility Alliance (WECA), is that an 802.11
614  * station will change its BSSID to match the "oldest" 802.11 ad hoc
615  * network, on the same channel, that has the station's desired SSID.
616  * The "oldest" 802.11 network sends beacons with the greatest TSF
617  * timestamp.
618  * The caller is assumed to validate TSF's before attempting a merge.
619  *
620  * Return B_TRUE if the BSSID changed, B_FALSE otherwise.
621  */
622 boolean_t
623 ieee80211_ibss_merge(ieee80211_node_t *in)
624 {
625 	ieee80211com_t *ic = in->in_ic;
626 
627 	if (in == ic->ic_bss ||
628 	    IEEE80211_ADDR_EQ(in->in_bssid, ic->ic_bss->in_bssid)) {
629 		/* unchanged, nothing to do */
630 		return (B_FALSE);
631 	}
632 	if (ieee80211_match_bss(ic, in) != 0) {	/* capabilities mismatch */
633 		ieee80211_dbg(IEEE80211_MSG_ASSOC, "ieee80211_ibss_merge: "
634 			" merge failed, capabilities mismatch\n");
635 		return (B_FALSE);
636 	}
637 	ieee80211_dbg(IEEE80211_MSG_ASSOC, "ieee80211_ibss_merge: "
638 		"new bssid %s: %s preamble, %s slot time%s\n",
639 		ieee80211_macaddr_sprintf(in->in_bssid),
640 		(ic->ic_flags & IEEE80211_F_SHPREAMBLE) ? "short" : "long",
641 		(ic->ic_flags & IEEE80211_F_SHSLOT) ? "short" : "long",
642 		(ic->ic_flags&IEEE80211_F_USEPROT) ? ", protection" : "");
643 	ieee80211_sta_join(ic, in);
644 	return (B_TRUE);
645 }
646 
647 /*
648  * Join the specified IBSS/BSS network.  The node is assumed to
649  * be passed in with a held reference.
650  */
651 void
652 ieee80211_sta_join(ieee80211com_t *ic, ieee80211_node_t *selbs)
653 {
654 	ieee80211_impl_t *im = ic->ic_private;
655 	ieee80211_node_t *obss;
656 
657 	IEEE80211_LOCK(ic);
658 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
659 		ieee80211_node_table_t *nt;
660 
661 		/*
662 		 * Delete unusable rates; we've already checked
663 		 * that the negotiated rate set is acceptable.
664 		 */
665 		(void) ieee80211_fix_rate(selbs, IEEE80211_F_DODEL);
666 		/*
667 		 * Fillin the neighbor table
668 		 */
669 		nt = &ic->ic_sta;
670 		IEEE80211_NODE_LOCK(nt);
671 		nt->nt_name = "neighbor";
672 		nt->nt_inact_init = im->im_inact_run;
673 		IEEE80211_NODE_UNLOCK(nt);
674 	}
675 
676 	/*
677 	 * Committed to selbs, setup state.
678 	 */
679 	obss = ic->ic_bss;
680 	ic->ic_bss = ieee80211_ref_node(selbs);	/* Grab reference */
681 	if (obss != NULL) {
682 		ieee80211_copy_bss(selbs, obss);
683 		ieee80211_free_node(obss);
684 	}
685 	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->in_chan);
686 	ic->ic_curchan = selbs->in_chan;
687 	/*
688 	 * Set the erp state (mostly the slot time) to deal with
689 	 * the auto-select case; this should be redundant if the
690 	 * mode is locked.
691 	 */
692 	ieee80211_reset_erp(ic);
693 
694 	IEEE80211_UNLOCK(ic);
695 	if (ic->ic_opmode == IEEE80211_M_STA)
696 		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
697 	else
698 		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
699 }
700 
701 /*
702  * Leave the specified IBSS/BSS network.  The node is assumed to
703  * be passed in with a held reference.
704  */
705 void
706 ieee80211_sta_leave(ieee80211com_t *ic, ieee80211_node_t *in)
707 {
708 	IEEE80211_LOCK(ic);
709 	ic->ic_node_cleanup(in);
710 	ieee80211_notify_node_leave(ic, in);
711 	IEEE80211_UNLOCK(ic);
712 }
713 
714 /*
715  * Allocate a node. This is the default callback function for
716  * ic_node_alloc. This function may be overridden by the driver
717  * to allocate device specific node structure.
718  */
719 /* ARGSUSED */
720 static ieee80211_node_t *
721 ieee80211_node_alloc(ieee80211com_t *ic)
722 {
723 	return (kmem_zalloc(sizeof (ieee80211_node_t), KM_SLEEP));
724 }
725 
726 /*
727  * Cleanup a node, free any memory associated with the node.
728  * This is the default callback function for ic_node_cleanup
729  * and may be overridden by the driver.
730  */
731 static void
732 ieee80211_node_cleanup(ieee80211_node_t *in)
733 {
734 	in->in_associd = 0;
735 	in->in_rssi = 0;
736 	in->in_rstamp = 0;
737 	if (in->in_challenge != NULL) {
738 		kmem_free(in->in_challenge, IEEE80211_CHALLENGE_LEN);
739 		in->in_challenge = NULL;
740 	}
741 	if (in->in_rxfrag != NULL) {
742 		freemsg(in->in_rxfrag);
743 		in->in_rxfrag = NULL;
744 	}
745 }
746 
747 /*
748  * Free a node. This is the default callback function for ic_node_free
749  * and may be overridden by the driver to free memory used by device
750  * specific node structure
751  */
752 static void
753 ieee80211_node_free(ieee80211_node_t *in)
754 {
755 	ieee80211com_t *ic = in->in_ic;
756 
757 	ic->ic_node_cleanup(in);
758 	kmem_free(in, sizeof (ieee80211_node_t));
759 }
760 
761 /*
762  * Get a node current RSSI value. This is the default callback function
763  * for ic_node_getrssi and may be overridden by the driver to provide
764  * device specific RSSI calculation algorithm.
765  */
766 static uint8_t
767 ieee80211_node_getrssi(const ieee80211_node_t *in)
768 {
769 	return (in->in_rssi);
770 }
771 
772 /* Free fragment if not needed anymore */
773 static void
774 node_cleanfrag(ieee80211_node_t *in)
775 {
776 	clock_t ticks;
777 
778 	ticks = ddi_get_lbolt();
779 	if (in->in_rxfrag != NULL && ticks > (in->in_rxfragstamp + hz)) {
780 		freemsg(in->in_rxfrag);
781 		in->in_rxfrag = NULL;
782 	}
783 }
784 
785 /*
786  * Setup a node. Initialize the node with specified macaddr. Associate
787  * with the interface softc, ic, and add it to the specified node
788  * database.
789  */
790 static void
791 ieee80211_setup_node(ieee80211com_t *ic, ieee80211_node_table_t *nt,
792     ieee80211_node_t *in, const uint8_t *macaddr)
793 {
794 	int32_t hash;
795 
796 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_setup_node(): "
797 		"%p<%s> in %s table\n", in,
798 		ieee80211_macaddr_sprintf(macaddr),
799 		(nt != NULL) ? nt->nt_name : "NULL");
800 
801 	in->in_ic = ic;
802 	IEEE80211_ADDR_COPY(in->in_macaddr, macaddr);
803 	hash = ieee80211_node_hash(macaddr);
804 	ieee80211_node_initref(in);		/* mark referenced */
805 	in->in_authmode = IEEE80211_AUTH_OPEN;
806 	in->in_txpower = ic->ic_txpowlimit;	/* max power */
807 	in->in_chan = IEEE80211_CHAN_ANYC;
808 	in->in_inact_reload = IEEE80211_INACT_INIT;
809 	in->in_inact = in->in_inact_reload;
810 	ieee80211_crypto_resetkey(ic, &in->in_ucastkey, IEEE80211_KEYIX_NONE);
811 
812 	if (nt != NULL) {
813 		IEEE80211_NODE_LOCK(nt);
814 		list_insert_tail(&nt->nt_node, in);
815 		list_insert_tail(&nt->nt_hash[hash], in);
816 		in->in_table = nt;
817 		in->in_inact_reload = nt->nt_inact_init;
818 		IEEE80211_NODE_UNLOCK(nt);
819 	}
820 }
821 
822 /*
823  * Allocates and initialize a node with specified MAC address.
824  * Associate the node with the interface ic. If the allocation
825  * is successful, the node structure is initialized by
826  * ieee80211_setup_node(); otherwise, NULL is returned
827  */
828 ieee80211_node_t *
829 ieee80211_alloc_node(ieee80211com_t *ic, ieee80211_node_table_t *nt,
830     const uint8_t *macaddr)
831 {
832 	ieee80211_node_t *in;
833 
834 	in = ic->ic_node_alloc(ic);
835 	if (in != NULL)
836 		ieee80211_setup_node(ic, nt, in, macaddr);
837 	return (in);
838 }
839 
840 /*
841  * Craft a temporary node suitable for sending a management frame
842  * to the specified station.  We craft only as much state as we
843  * need to do the work since the node will be immediately reclaimed
844  * once the send completes.
845  */
846 ieee80211_node_t *
847 ieee80211_tmp_node(ieee80211com_t *ic, const uint8_t *macaddr)
848 {
849 	ieee80211_node_t *in;
850 
851 	in = ic->ic_node_alloc(ic);
852 	if (in != NULL) {
853 		ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_tmp_node: "
854 			"%p<%s>\n", in, ieee80211_macaddr_sprintf(macaddr));
855 
856 		IEEE80211_ADDR_COPY(in->in_macaddr, macaddr);
857 		IEEE80211_ADDR_COPY(in->in_bssid, ic->ic_bss->in_bssid);
858 		ieee80211_node_initref(in);		/* mark referenced */
859 		in->in_txpower = ic->ic_bss->in_txpower;
860 		/* NB: required by ieee80211_fix_rate */
861 		ieee80211_node_setchan(ic, in, ic->ic_bss->in_chan);
862 		ieee80211_crypto_resetkey(ic, &in->in_ucastkey,
863 			IEEE80211_KEYIX_NONE);
864 
865 		in->in_table = NULL;		/* NB: pedantic */
866 		in->in_ic = ic;
867 	}
868 
869 	return (in);
870 }
871 
872 /*
873  * ieee80211_dup_bss() is similar to ieee80211_alloc_node(),
874  * but is instead used to create a node database entry for
875  * the specified BSSID. If the allocation is successful, the
876  * node is initialized,  otherwise, NULL is returned.
877  */
878 ieee80211_node_t *
879 ieee80211_dup_bss(ieee80211_node_table_t *nt, const uint8_t *macaddr)
880 {
881 	ieee80211com_t *ic = nt->nt_ic;
882 	ieee80211_node_t *in;
883 
884 	in = ieee80211_alloc_node(ic, nt, macaddr);
885 	if (in != NULL) {
886 		/*
887 		 * Inherit from ic_bss.
888 		 */
889 		ieee80211_copy_bss(in, ic->ic_bss);
890 		IEEE80211_ADDR_COPY(in->in_bssid, ic->ic_bss->in_bssid);
891 		ieee80211_node_setchan(ic, in, ic->ic_bss->in_chan);
892 	}
893 
894 	return (in);
895 }
896 
897 /*
898  * Iterate through the node table, searching for a node entry which
899  * matches macaddr. If the entry is found, its reference count is
900  * incremented, and a pointer to the node is returned; otherwise,
901  * NULL will be returned.
902  * The node table lock is acquired by the caller.
903  */
904 static ieee80211_node_t *
905 ieee80211_find_node_locked(ieee80211_node_table_t *nt, const uint8_t *macaddr)
906 {
907 	ieee80211_node_t *in;
908 	int hash;
909 
910 	ASSERT(IEEE80211_NODE_IS_LOCKED(nt));
911 
912 	hash = ieee80211_node_hash(macaddr);
913 	in = list_head(&nt->nt_hash[hash]);
914 	while (in != NULL) {
915 		if (IEEE80211_ADDR_EQ(in->in_macaddr, macaddr))
916 			return (ieee80211_ref_node(in)); /* mark referenced */
917 		in = list_next(&nt->nt_hash[hash], in);
918 	}
919 	return (NULL);
920 }
921 
922 /*
923  * Iterate through the node table, searching for a node entry
924  * which match specified mac address.
925  * Return NULL if no matching node found.
926  */
927 ieee80211_node_t *
928 ieee80211_find_node(ieee80211_node_table_t *nt, const uint8_t *macaddr)
929 {
930 	ieee80211_node_t *in;
931 
932 	IEEE80211_NODE_LOCK(nt);
933 	in = ieee80211_find_node_locked(nt, macaddr);
934 	IEEE80211_NODE_UNLOCK(nt);
935 	return (in);
936 }
937 
938 /*
939  * Fake up a node; this handles node discovery in adhoc mode.
940  * Note that for the driver's benefit we treat this like an
941  * association so the driver has an opportunity to setup it's
942  * private state.
943  */
944 ieee80211_node_t *
945 ieee80211_fakeup_adhoc_node(ieee80211_node_table_t *nt, const uint8_t *macaddr)
946 {
947 	ieee80211com_t *ic = nt->nt_ic;
948 	ieee80211_node_t *in;
949 
950 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_fakeup_adhoc_node: "
951 		"mac<%s>\n", ieee80211_macaddr_sprintf(macaddr));
952 	in = ieee80211_dup_bss(nt, macaddr);
953 	if (in != NULL) {
954 		/* no rate negotiation; just dup */
955 		in->in_rates = ic->ic_bss->in_rates;
956 		if (ic->ic_node_newassoc != NULL)
957 			ic->ic_node_newassoc(in, 1);
958 		ieee80211_node_authorize(in);
959 	}
960 	return (in);
961 }
962 
963 /*
964  * Process a beacon or probe response frame.
965  */
966 void
967 ieee80211_add_scan(ieee80211com_t *ic, const struct ieee80211_scanparams *sp,
968     const struct ieee80211_frame *wh, int subtype, int rssi, int rstamp)
969 {
970 	ieee80211_node_table_t *nt = &ic->ic_scan;
971 	ieee80211_node_t *in;
972 	boolean_t newnode = B_FALSE;
973 
974 	in = ieee80211_find_node(nt, wh->i_addr2);
975 	if (in == NULL) {
976 		/*
977 		 * Create a new entry.
978 		 */
979 		in = ieee80211_alloc_node(ic, nt, wh->i_addr2);
980 		if (in == NULL) {
981 			ieee80211_dbg(IEEE80211_MSG_ANY, "ieee80211_add_scan: "
982 				"alloc node failed\n");
983 			return;
984 		}
985 		/*
986 		 * inherit from ic_bss.
987 		 */
988 		ieee80211_copy_bss(in, ic->ic_bss);
989 		ieee80211_node_setchan(ic, in, ic->ic_curchan);
990 		newnode = B_TRUE;
991 	}
992 
993 	/* ap beaconing multiple ssid w/ same bssid */
994 
995 	/*
996 	 * sp->ssid[0] - element ID
997 	 * sp->ssid[1] - length
998 	 * sp->ssid[2]... - ssid
999 	 */
1000 	if (sp->ssid[1] != 0 &&
1001 	    subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP ||
1002 	    in->in_esslen == 0) {
1003 		in->in_esslen = sp->ssid[1];
1004 		bzero(in->in_essid, sizeof (in->in_essid));
1005 		bcopy(sp->ssid + 2, in->in_essid, sp->ssid[1]);
1006 	}
1007 	IEEE80211_ADDR_COPY(in->in_bssid, wh->i_addr3);
1008 	in->in_rssi = (uint8_t)rssi;
1009 	in->in_rstamp = rstamp;
1010 	bcopy(sp->tstamp, in->in_tstamp.data, sizeof (in->in_tstamp));
1011 	in->in_intval = sp->bintval;
1012 	in->in_capinfo = sp->capinfo;
1013 	in->in_chan = &ic->ic_sup_channels[sp->chan];
1014 	in->in_phytype = sp->phytype;
1015 	in->in_fhdwell = sp->fhdwell;
1016 	in->in_fhindex = sp->fhindex;
1017 	in->in_erp = sp->erp;
1018 	if (sp->tim != NULL) {
1019 		struct ieee80211_tim_ie *ie;
1020 
1021 		ie = (struct ieee80211_tim_ie *)sp->tim;
1022 		in->in_dtim_count = ie->tim_count;
1023 		in->in_dtim_period = ie->tim_period;
1024 	}
1025 	/*
1026 	 * Record the byte offset from the mac header to
1027 	 * the start of the TIM information element for
1028 	 * use by hardware and/or to speedup software
1029 	 * processing of beacon frames.
1030 	 */
1031 	in->in_tim_off = sp->timoff;
1032 
1033 	/* NB: must be after in_chan is setup */
1034 	(void) ieee80211_setup_rates(in, sp->rates, sp->xrates,
1035 		IEEE80211_F_DOSORT);
1036 
1037 	if (!newnode)
1038 		ieee80211_free_node(in);
1039 }
1040 
1041 /*
1042  * Initialize/update an ad-hoc node with contents from a received
1043  * beacon frame.
1044  */
1045 void
1046 ieee80211_init_neighbor(ieee80211_node_t *in, const struct ieee80211_frame *wh,
1047     const struct ieee80211_scanparams *sp)
1048 {
1049 	in->in_esslen = sp->ssid[1];
1050 	(void) memcpy(in->in_essid, sp->ssid + 2, sp->ssid[1]);
1051 	IEEE80211_ADDR_COPY(in->in_bssid, wh->i_addr3);
1052 	(void) memcpy(in->in_tstamp.data, sp->tstamp, sizeof (in->in_tstamp));
1053 	in->in_intval = sp->bintval;
1054 	in->in_capinfo = sp->capinfo;
1055 	in->in_chan = in->in_ic->ic_curchan;
1056 	in->in_fhdwell = sp->fhdwell;
1057 	in->in_fhindex = sp->fhindex;
1058 	in->in_erp = sp->erp;
1059 	in->in_tim_off = sp->timoff;
1060 
1061 	/* NB: must be after in_chan is setup */
1062 	(void) ieee80211_setup_rates(in, sp->rates, sp->xrates,
1063 		IEEE80211_F_DOSORT);
1064 }
1065 
1066 /*
1067  * Do node discovery in adhoc mode on receipt of a beacon
1068  * or probe response frame.  Note that for the driver's
1069  * benefit we we treat this like an association so the
1070  * driver has an opportuinty to setup it's private state.
1071  */
1072 ieee80211_node_t *
1073 ieee80211_add_neighbor(ieee80211com_t *ic, const struct ieee80211_frame *wh,
1074     const struct ieee80211_scanparams *sp)
1075 {
1076 	ieee80211_node_t *in;
1077 
1078 	in = ieee80211_dup_bss(&ic->ic_sta, wh->i_addr2);
1079 	if (in != NULL) {
1080 		ieee80211_init_neighbor(in, wh, sp);
1081 		if (ic->ic_node_newassoc != NULL)
1082 			ic->ic_node_newassoc(in, 1);
1083 	}
1084 	return (in);
1085 }
1086 
1087 #define	IEEE80211_IS_CTL(wh) \
1088 	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1089 
1090 /*
1091  * Locate the node for sender, track state, and then pass the
1092  * (referenced) node up to the 802.11 layer for its use.  We
1093  * are required to pass some node so we fall back to ic_bss
1094  * when this frame is from an unknown sender.  The 802.11 layer
1095  * knows this means the sender wasn't in the node table and
1096  * acts accordingly.
1097  */
1098 ieee80211_node_t *
1099 ieee80211_find_rxnode(ieee80211com_t *ic, const struct ieee80211_frame *wh)
1100 {
1101 	ieee80211_node_table_t *nt;
1102 	ieee80211_node_t *in;
1103 
1104 	/* may want scanned nodes in the neighbor table for adhoc */
1105 	if (ic->ic_opmode == IEEE80211_M_STA ||
1106 	    (ic->ic_flags & IEEE80211_F_SCAN)) {
1107 		nt = &ic->ic_scan;
1108 	} else {
1109 		nt = &ic->ic_sta;
1110 	}
1111 
1112 	IEEE80211_NODE_LOCK(nt);
1113 	if (IEEE80211_IS_CTL(wh))
1114 		in = ieee80211_find_node_locked(nt, wh->i_addr1);
1115 	else
1116 		in = ieee80211_find_node_locked(nt, wh->i_addr2);
1117 	IEEE80211_NODE_UNLOCK(nt);
1118 
1119 	if (in == NULL)
1120 		in = ieee80211_ref_node(ic->ic_bss);
1121 
1122 	return (in);
1123 }
1124 
1125 /*
1126  * Return a reference to the appropriate node for sending
1127  * a data frame.  This handles node discovery in adhoc networks.
1128  */
1129 ieee80211_node_t *
1130 ieee80211_find_txnode(ieee80211com_t *ic, const uint8_t *daddr)
1131 {
1132 	ieee80211_node_table_t *nt = &ic->ic_sta;
1133 	ieee80211_node_t *in;
1134 
1135 	/*
1136 	 * The destination address should be in the node table
1137 	 * unless this is a multicast/broadcast frame.  We can
1138 	 * also optimize station mode operation, all frames go
1139 	 * to the bss node.
1140 	 */
1141 	IEEE80211_NODE_LOCK(nt);
1142 	if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(daddr))
1143 		in = ieee80211_ref_node(ic->ic_bss);
1144 	else
1145 		in = ieee80211_find_node_locked(nt, daddr);
1146 	IEEE80211_NODE_UNLOCK(nt);
1147 
1148 	if (in == NULL) {
1149 		if (ic->ic_opmode == IEEE80211_M_IBSS) {
1150 			/*
1151 			 * In adhoc mode cons up a node for the destination.
1152 			 * Note that we need an additional reference for the
1153 			 * caller to be consistent with
1154 			 * ieee80211_find_node_locked
1155 			 * can't hold lock across ieee80211_dup_bss 'cuz of
1156 			 * recursive locking
1157 			 */
1158 			in = ieee80211_fakeup_adhoc_node(nt, daddr);
1159 			if (in != NULL)
1160 				(void) ieee80211_ref_node(in);
1161 		} else {
1162 			ieee80211_dbg(IEEE80211_MSG_OUTPUT,
1163 				"ieee80211_find_txnode: "
1164 				"[%s] no node, discard frame\n",
1165 				ieee80211_macaddr_sprintf(daddr));
1166 		}
1167 	}
1168 	return (in);
1169 }
1170 
1171 /*
1172  * Remove a node from the node database entries and free memory
1173  * associated with the node. The node table lock is acquired by
1174  * the caller.
1175  */
1176 static void
1177 ieee80211_free_node_locked(ieee80211_node_t *in)
1178 {
1179 	ieee80211com_t *ic = in->in_ic;
1180 	ieee80211_node_table_t *nt = in->in_table;
1181 	int32_t hash;
1182 
1183 	if (nt != NULL) {
1184 		hash = ieee80211_node_hash(in->in_macaddr);
1185 		list_remove(&nt->nt_hash[hash], in);
1186 		list_remove(&nt->nt_node, in);
1187 	}
1188 	ic->ic_node_free(in);
1189 }
1190 
1191 /*
1192  * Remove a node from the node database entries and free any
1193  * memory associated with the node.
1194  * This method can be overridden in ieee80211_attach()
1195  */
1196 void
1197 ieee80211_free_node(ieee80211_node_t *in)
1198 {
1199 	ieee80211_node_table_t *nt = in->in_table;
1200 
1201 	if (nt != NULL)
1202 		IEEE80211_NODE_LOCK(nt);
1203 	if (ieee80211_node_decref_nv(in) == 0)
1204 		ieee80211_free_node_locked(in);
1205 	if (nt != NULL)
1206 		IEEE80211_NODE_UNLOCK(nt);
1207 }
1208 
1209 /*
1210  * Reclaim a node.  If this is the last reference count then
1211  * do the normal free work.  Otherwise remove it from the node
1212  * table and mark it gone by clearing the back-reference.
1213  */
1214 static void
1215 ieee80211_node_reclaim(ieee80211_node_table_t *nt, ieee80211_node_t *in)
1216 {
1217 	int32_t hash;
1218 
1219 	IEEE80211_NODE_LOCK_ASSERT(nt);
1220 	ieee80211_dbg(IEEE80211_MSG_NODE, "node_reclaim: "
1221 		" remove %p<%s> from %s table, refcnt %d\n",
1222 		in, ieee80211_macaddr_sprintf(in->in_macaddr), nt->nt_name,
1223 		ieee80211_node_refcnt(in));
1224 
1225 	if (ieee80211_node_decref_nv(in) != 0) {
1226 		/*
1227 		 * Clear any entry in the unicast key mapping table.
1228 		 * We need to do it here so rx lookups don't find it
1229 		 * in the mapping table even if it's not in the hash
1230 		 * table.  We cannot depend on the mapping table entry
1231 		 * being cleared because the node may not be free'd.
1232 		 */
1233 		hash = ieee80211_node_hash(in->in_macaddr);
1234 		list_remove(&nt->nt_hash[hash], in);
1235 		list_remove(&nt->nt_node, in);
1236 		in->in_table = NULL;
1237 	} else {
1238 		ieee80211_free_node_locked(in);
1239 	}
1240 }
1241 
1242 /*
1243  * Iterate through the node list and reclaim all node in the node table.
1244  * The node table lock is acquired by the caller
1245  */
1246 static void
1247 ieee80211_free_allnodes_locked(ieee80211_node_table_t *nt)
1248 {
1249 	ieee80211_node_t *in;
1250 
1251 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_free_allnodes_locked(): "
1252 		"free all nodes in %s table\n", nt->nt_name);
1253 
1254 	in = list_head(&nt->nt_node);
1255 	while (in != NULL) {
1256 		ieee80211_node_reclaim(nt, in);
1257 		in = list_head(&nt->nt_node);
1258 	}
1259 	ieee80211_reset_erp(nt->nt_ic);
1260 }
1261 
1262 /*
1263  * Iterate through the node list, calling ieee80211_node_reclaim() for
1264  * all nodes associated with the interface.
1265  */
1266 static void
1267 ieee80211_free_allnodes(ieee80211_node_table_t *nt)
1268 {
1269 	IEEE80211_NODE_LOCK(nt);
1270 	ieee80211_free_allnodes_locked(nt);
1271 	IEEE80211_NODE_UNLOCK(nt);
1272 }
1273 
1274 /*
1275  * Timeout entries in the scan cache. This is the timeout callback
1276  * function of node table ic_scan which is called when the inactivity
1277  * timer expires.
1278  */
1279 static void
1280 ieee80211_timeout_scan_candidates(ieee80211_node_table_t *nt)
1281 {
1282 	ieee80211com_t *ic = nt->nt_ic;
1283 	ieee80211_node_t *in;
1284 
1285 	IEEE80211_NODE_LOCK(nt);
1286 	in = ic->ic_bss;
1287 	node_cleanfrag(in);	/* Free fragment if not needed */
1288 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1289 	IEEE80211_NODE_UNLOCK(nt);
1290 }
1291 
1292 /*
1293  * Timeout inactive stations and do related housekeeping.
1294  * Note that we cannot hold the node lock while sending a
1295  * frame as this would lead to a LOR.  Instead we use a
1296  * generation number to mark nodes that we've scanned and
1297  * drop the lock and restart a scan if we have to time out
1298  * a node.  Since we are single-threaded by virtue of
1299  * controlling the inactivity timer we can be sure this will
1300  * process each node only once.
1301  */
1302 static void
1303 ieee80211_timeout_stations(ieee80211_node_table_t *nt)
1304 {
1305 	ieee80211com_t *ic = nt->nt_ic;
1306 	ieee80211_impl_t *im = ic->ic_private;
1307 	ieee80211_node_t *in = NULL;
1308 	uint32_t gen;
1309 	boolean_t isadhoc;
1310 
1311 	IEEE80211_LOCK_ASSERT(ic);
1312 	isadhoc = (ic->ic_opmode == IEEE80211_M_IBSS ||
1313 		ic->ic_opmode == IEEE80211_M_AHDEMO);
1314 	IEEE80211_SCAN_LOCK(nt);
1315 	gen = ++nt->nt_scangen;
1316 restart:
1317 	IEEE80211_NODE_LOCK(nt);
1318 	for (in = list_head(&nt->nt_node); in != NULL;
1319 		in = list_next(&nt->nt_node, in)) {
1320 		if (in->in_scangen == gen)	/* previously handled */
1321 			continue;
1322 		in->in_scangen = gen;
1323 		node_cleanfrag(in);	/* free fragment if not needed */
1324 
1325 		/*
1326 		 * Special case ourself; we may be idle for extended periods
1327 		 * of time and regardless reclaiming our state is wrong.
1328 		 */
1329 		if (in == ic->ic_bss)
1330 			continue;
1331 		in->in_inact--;
1332 		if (in->in_associd != 0 || isadhoc) {
1333 			/*
1334 			 * Probe the station before time it out.  We
1335 			 * send a null data frame which may not be
1336 			 * uinversally supported by drivers (need it
1337 			 * for ps-poll support so it should be...).
1338 			 */
1339 			if (0 < in->in_inact &&
1340 			    in->in_inact <= im->im_inact_probe) {
1341 				ieee80211_dbg(IEEE80211_MSG_NODE, "net80211: "
1342 					"probe station due to inactivity\n");
1343 				IEEE80211_NODE_UNLOCK(nt);
1344 				IEEE80211_UNLOCK(ic);
1345 				(void) ieee80211_send_nulldata(in);
1346 				IEEE80211_LOCK(ic);
1347 				goto restart;
1348 			}
1349 		}
1350 		if (in->in_inact <= 0) {
1351 			ieee80211_dbg(IEEE80211_MSG_NODE, "net80211: "
1352 				"station timed out due to inact (refcnt %u)\n",
1353 				ieee80211_node_refcnt(in));
1354 			/*
1355 			 * Send a deauthenticate frame and drop the station.
1356 			 * This is somewhat complicated due to reference counts
1357 			 * and locking.  At this point a station will typically
1358 			 * have a reference count of 1.  ieee80211_node_leave
1359 			 * will do a "free" of the node which will drop the
1360 			 * reference count.  But in the meantime a reference
1361 			 * wil be held by the deauth frame.  The actual reclaim
1362 			 * of the node will happen either after the tx is
1363 			 * completed or by ieee80211_node_leave.
1364 			 *
1365 			 * Separately we must drop the node lock before sending
1366 			 * in case the driver takes a lock, as this will result
1367 			 * in  LOR between the node lock and the driver lock.
1368 			 */
1369 			IEEE80211_NODE_UNLOCK(nt);
1370 			if (in->in_associd != 0) {
1371 				IEEE80211_UNLOCK(ic);
1372 				IEEE80211_SEND_MGMT(ic, in,
1373 					IEEE80211_FC0_SUBTYPE_DEAUTH,
1374 					IEEE80211_REASON_AUTH_EXPIRE);
1375 				IEEE80211_LOCK(ic);
1376 			}
1377 			ieee80211_node_leave(ic, in);
1378 			goto restart;
1379 		}
1380 	}
1381 	IEEE80211_NODE_UNLOCK(nt);
1382 
1383 	IEEE80211_SCAN_UNLOCK(nt);
1384 
1385 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1386 }
1387 
1388 /*
1389  * Call the user-defined call back function for all nodes in
1390  * the node cache. The callback is invoked with the user-supplied
1391  * value and a pointer to the current node.
1392  */
1393 void
1394 ieee80211_iterate_nodes(ieee80211_node_table_t *nt, ieee80211_iter_func *f,
1395     void *arg)
1396 {
1397 	ieee80211_node_t *in;
1398 
1399 	IEEE80211_NODE_LOCK(nt);
1400 	in = list_head(&nt->nt_node);
1401 	while (in != NULL) {
1402 		(void) ieee80211_ref_node(in);
1403 		IEEE80211_NODE_UNLOCK(nt);
1404 		(*f)(arg, in);
1405 		ieee80211_free_node(in);
1406 		IEEE80211_NODE_LOCK(nt);
1407 		in = list_next(&nt->nt_node, in);
1408 	}
1409 	IEEE80211_NODE_UNLOCK(nt);
1410 }
1411 
1412 /*
1413  * Handle bookkeeping for station deauthentication/disassociation
1414  * when operating as an ap.
1415  */
1416 static void
1417 ieee80211_node_leave(ieee80211com_t *ic, ieee80211_node_t *in)
1418 {
1419 	ieee80211_node_table_t *nt = in->in_table;
1420 
1421 	ASSERT(ic->ic_opmode == IEEE80211_M_IBSS);
1422 
1423 	/*
1424 	 * Remove the node from any table it's recorded in and
1425 	 * drop the caller's reference.  Removal from the table
1426 	 * is important to insure the node is not reprocessed
1427 	 * for inactivity.
1428 	 */
1429 	if (nt != NULL) {
1430 		IEEE80211_NODE_LOCK(nt);
1431 		ieee80211_node_reclaim(nt, in);
1432 		IEEE80211_NODE_UNLOCK(nt);
1433 	} else {
1434 		ieee80211_free_node(in);
1435 	}
1436 }
1437 
1438 /*
1439  * Initialize a node table with specified name, inactivity timer value
1440  * and callback inactivity timeout function. Associate the node table
1441  * with interface softc, ic.
1442  */
1443 static void
1444 ieee80211_node_table_init(ieee80211com_t *ic, ieee80211_node_table_t *nt,
1445     const char *name, int inact, int keyixmax,
1446     void (*timeout)(ieee80211_node_table_t *))
1447 {
1448 	int i;
1449 
1450 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_node_table_init():"
1451 		"%s table, inact %d\n", name, inact);
1452 
1453 	nt->nt_ic = ic;
1454 	nt->nt_name = name;
1455 	nt->nt_inact_timer = 0;
1456 	nt->nt_inact_init = inact;
1457 	nt->nt_timeout = timeout;
1458 	nt->nt_keyixmax = keyixmax;
1459 	nt->nt_scangen = 1;
1460 	mutex_init(&nt->nt_scanlock, NULL, MUTEX_DRIVER, NULL);
1461 	mutex_init(&nt->nt_nodelock, NULL, MUTEX_DRIVER, NULL);
1462 
1463 	list_create(&nt->nt_node, sizeof (ieee80211_node_t),
1464 		offsetof(ieee80211_node_t, in_node));
1465 	for (i = 0; i < IEEE80211_NODE_HASHSIZE; i++) {
1466 		list_create(&nt->nt_hash[i], sizeof (ieee80211_node_t),
1467 			offsetof(ieee80211_node_t, in_hash));
1468 	}
1469 }
1470 
1471 /*
1472  * Reset a node table. Clean its inactivity timer and call
1473  * ieee80211_free_allnodes_locked() to free all nodes in the
1474  * node table.
1475  */
1476 void
1477 ieee80211_node_table_reset(ieee80211_node_table_t *nt)
1478 {
1479 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_node_table_reset(): "
1480 		"%s table\n", nt->nt_name);
1481 
1482 	IEEE80211_NODE_LOCK(nt);
1483 	nt->nt_inact_timer = 0;
1484 	ieee80211_free_allnodes_locked(nt);
1485 	IEEE80211_NODE_UNLOCK(nt);
1486 }
1487 
1488 /*
1489  * Destroy a node table. Free all nodes in the node table.
1490  * This function is usually called by node detach function.
1491  */
1492 static void
1493 ieee80211_node_table_cleanup(ieee80211_node_table_t *nt)
1494 {
1495 	ieee80211_dbg(IEEE80211_MSG_NODE, "ieee80211_node_table_cleanup(): "
1496 	    "%s table\n", nt->nt_name);
1497 
1498 	IEEE80211_NODE_LOCK(nt);
1499 	ieee80211_free_allnodes_locked(nt);
1500 	IEEE80211_NODE_UNLOCK(nt);
1501 	mutex_destroy(&nt->nt_nodelock);
1502 	mutex_destroy(&nt->nt_scanlock);
1503 }
1504