ieee80211_node.c revision 140454
1/*-
2 * Copyright (c) 2001 Atsushi Onoe
3 * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * Alternatively, this software may be distributed under the terms of the
18 * GNU General Public License ("GPL") version 2 as published by the Free
19 * Software Foundation.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_node.c 140454 2005-01-18 20:34:22Z sam $");
35
36#include <sys/param.h>
37#include <sys/systm.h>
38#include <sys/mbuf.h>
39#include <sys/malloc.h>
40#include <sys/kernel.h>
41
42#include <sys/socket.h>
43
44#include <net/if.h>
45#include <net/if_media.h>
46#include <net/ethernet.h>
47
48#include <net80211/ieee80211_var.h>
49
50#include <net/bpf.h>
51
52static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
53static void node_cleanup(struct ieee80211_node *);
54static void node_free(struct ieee80211_node *);
55static u_int8_t node_getrssi(const struct ieee80211_node *);
56
57static void ieee80211_setup_node(struct ieee80211_node_table *,
58		struct ieee80211_node *, const u_int8_t *);
59static void _ieee80211_free_node(struct ieee80211_node *);
60static void ieee80211_free_allnodes(struct ieee80211_node_table *);
61
62static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
63static void ieee80211_timeout_stations(struct ieee80211_node_table *);
64
65static void ieee80211_set_tim(struct ieee80211com *,
66		struct ieee80211_node *, int set);
67
68static void ieee80211_node_table_init(struct ieee80211com *ic,
69	struct ieee80211_node_table *nt, const char *name, int inact,
70	void (*timeout)(struct ieee80211_node_table *));
71static struct ieee80211_node_table *ieee80211_node_table_alloc(
72	struct ieee80211com *ic, const char *name, int inact,
73	void (*timeout)(struct ieee80211_node_table *));
74static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
75
76MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
77
78void
79ieee80211_node_attach(struct ieee80211com *ic)
80{
81
82	ic->ic_sta = NULL;		/* defer to when we need it */
83	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
84		IEEE80211_INACT_SCAN, ieee80211_timeout_scan_candidates);
85
86	ic->ic_node_alloc = node_alloc;
87	ic->ic_node_free = node_free;
88	ic->ic_node_cleanup = node_cleanup;
89	ic->ic_node_getrssi = node_getrssi;
90
91	/* default station inactivity timer setings */
92	ic->ic_inact_init = IEEE80211_INACT_INIT;
93	ic->ic_inact_auth = IEEE80211_INACT_AUTH;
94	ic->ic_inact_run = IEEE80211_INACT_RUN;
95	ic->ic_inact_probe = IEEE80211_INACT_PROBE;
96
97	/* XXX defer */
98	if (ic->ic_max_aid == 0)
99		ic->ic_max_aid = IEEE80211_AID_DEF;
100	else if (ic->ic_max_aid > IEEE80211_AID_MAX)
101		ic->ic_max_aid = IEEE80211_AID_MAX;
102	MALLOC(ic->ic_aid_bitmap, u_int32_t *,
103		howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
104		M_DEVBUF, M_NOWAIT | M_ZERO);
105	if (ic->ic_aid_bitmap == NULL) {
106		/* XXX no way to recover */
107		printf("%s: no memory for AID bitmap!\n", __func__);
108		ic->ic_max_aid = 0;
109	}
110
111	/* XXX defer until using hostap/ibss mode */
112	ic->ic_tim_len = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
113	MALLOC(ic->ic_tim_bitmap, u_int8_t *, ic->ic_tim_len,
114		M_DEVBUF, M_NOWAIT | M_ZERO);
115	if (ic->ic_tim_bitmap == NULL) {
116		/* XXX no way to recover */
117		printf("%s: no memory for TIM bitmap!\n", __func__);
118	}
119	ic->ic_set_tim = ieee80211_set_tim;	/* NB: driver should override */
120}
121
122void
123ieee80211_node_lateattach(struct ieee80211com *ic)
124{
125	struct ieee80211_node *ni;
126	struct ieee80211_rsnparms *rsn;
127
128	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
129	KASSERT(ni != NULL, ("unable to setup inital BSS node"));
130	/*
131	 * Setup "global settings" in the bss node so that
132	 * each new station automatically inherits them.
133	 */
134	rsn = &ni->ni_rsn;
135	/* WEP, TKIP, and AES-CCM are always supported */
136	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
137	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
138	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
139	if (ic->ic_caps & IEEE80211_C_AES)
140		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
141	if (ic->ic_caps & IEEE80211_C_CKIP)
142		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
143	/*
144	 * Default unicast cipher to WEP for 802.1x use.  If
145	 * WPA is enabled the management code will set these
146	 * values to reflect.
147	 */
148	rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
149	rsn->rsn_ucastkeylen = 104 / NBBY;
150	/*
151	 * WPA says the multicast cipher is the lowest unicast
152	 * cipher supported.  But we skip WEP which would
153	 * otherwise be used based on this criteria.
154	 */
155	rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
156	rsn->rsn_mcastkeylen = 128 / NBBY;
157
158	/*
159	 * We support both WPA-PSK and 802.1x; the one used
160	 * is determined by the authentication mode and the
161	 * setting of the PSK state.
162	 */
163	rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
164	rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
165
166	ic->ic_bss = ieee80211_ref_node(ni);		/* hold reference */
167	ic->ic_auth = ieee80211_authenticator_get(ni->ni_authmode);
168}
169
170void
171ieee80211_node_detach(struct ieee80211com *ic)
172{
173
174	if (ic->ic_bss != NULL) {
175		ieee80211_free_node(ic->ic_bss);
176		ic->ic_bss = NULL;
177	}
178	ieee80211_node_table_cleanup(&ic->ic_scan);
179	if (ic->ic_sta != NULL) {
180		ieee80211_node_table_free(ic->ic_sta);
181		ic->ic_sta = NULL;
182	}
183	if (ic->ic_aid_bitmap != NULL) {
184		FREE(ic->ic_aid_bitmap, M_DEVBUF);
185		ic->ic_aid_bitmap = NULL;
186	}
187	if (ic->ic_tim_bitmap != NULL) {
188		FREE(ic->ic_tim_bitmap, M_DEVBUF);
189		ic->ic_tim_bitmap = NULL;
190	}
191}
192
193/*
194 * Port authorize/unauthorize interfaces for use by an authenticator.
195 */
196
197void
198ieee80211_node_authorize(struct ieee80211com *ic, struct ieee80211_node *ni)
199{
200	ni->ni_flags |= IEEE80211_NODE_AUTH;
201	ni->ni_inact_reload = ic->ic_inact_run;
202}
203
204void
205ieee80211_node_unauthorize(struct ieee80211com *ic, struct ieee80211_node *ni)
206{
207	ni->ni_flags &= ~IEEE80211_NODE_AUTH;
208}
209
210/*
211 * Set/change the channel.  The rate set is also updated as
212 * to insure a consistent view by drivers.
213 */
214static __inline void
215ieee80211_set_chan(struct ieee80211com *ic,
216	struct ieee80211_node *ni, struct ieee80211_channel *chan)
217{
218	ni->ni_chan = chan;
219	ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
220}
221
222/*
223 * AP scanning support.
224 */
225
226#ifdef IEEE80211_DEBUG
227static void
228dump_chanlist(const u_char chans[])
229{
230	const char *sep;
231	int i;
232
233	sep = " ";
234	for (i = 0; i < IEEE80211_CHAN_MAX; i++)
235		if (isset(chans, i)) {
236			printf("%s%u", sep, i);
237			sep = ", ";
238		}
239}
240#endif /* IEEE80211_DEBUG */
241
242/*
243 * Initialize the channel set to scan based on the
244 * of available channels and the current PHY mode.
245 */
246static void
247ieee80211_reset_scan(struct ieee80211com *ic)
248{
249
250	/* XXX ic_des_chan should be handled with ic_chan_active */
251	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
252		memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
253		setbit(ic->ic_chan_scan,
254			ieee80211_chan2ieee(ic, ic->ic_des_chan));
255	} else
256		memcpy(ic->ic_chan_scan, ic->ic_chan_active,
257			sizeof(ic->ic_chan_active));
258	/* NB: hack, setup so next_scan starts with the first channel */
259	if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC)
260		ieee80211_set_chan(ic, ic->ic_bss,
261			&ic->ic_channels[IEEE80211_CHAN_MAX]);
262#ifdef IEEE80211_DEBUG
263	if (ieee80211_msg_scan(ic)) {
264		printf("%s: scan set:", __func__);
265		dump_chanlist(ic->ic_chan_scan);
266		printf(" start chan %u\n",
267			ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan));
268	}
269#endif /* IEEE80211_DEBUG */
270}
271
272/*
273 * Begin an active scan.
274 */
275void
276ieee80211_begin_scan(struct ieee80211com *ic, int reset)
277{
278
279	ic->ic_scan.nt_scangen++;
280	/*
281	 * In all but hostap mode scanning starts off in
282	 * an active mode before switching to passive.
283	 */
284	if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
285		ic->ic_flags |= IEEE80211_F_ASCAN;
286		ic->ic_stats.is_scan_active++;
287	} else
288		ic->ic_stats.is_scan_passive++;
289	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
290		"begin %s scan in %s mode, scangen %u\n",
291		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
292		ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
293	/*
294	 * Clear scan state and flush any previously seen AP's.
295	 */
296	ieee80211_reset_scan(ic);
297	if (reset)
298		ieee80211_free_allnodes(&ic->ic_scan);
299
300	ic->ic_flags |= IEEE80211_F_SCAN;
301
302	/* Scan the next channel. */
303	ieee80211_next_scan(ic);
304}
305
306/*
307 * Switch to the next channel marked for scanning.
308 */
309int
310ieee80211_next_scan(struct ieee80211com *ic)
311{
312	struct ieee80211_channel *chan;
313
314	/*
315	 * Insure any previous mgt frame timeouts don't fire.
316	 * This assumes the driver does the right thing in
317	 * flushing anything queued in the driver and below.
318	 */
319	ic->ic_mgt_timer = 0;
320
321	chan = ic->ic_bss->ni_chan;
322	do {
323		if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
324			chan = &ic->ic_channels[0];
325		if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
326			clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
327			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
328			    "%s: chan %d->%d\n", __func__,
329			    ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan),
330			    ieee80211_chan2ieee(ic, chan));
331			ieee80211_set_chan(ic, ic->ic_bss, chan);
332#ifdef notyet
333			/* XXX driver state change */
334			/*
335			 * Scan next channel. If doing an active scan
336			 * and the channel is not marked passive-only
337			 * then send a probe request.  Otherwise just
338			 * listen for beacons on the channel.
339			 */
340			if ((ic->ic_flags & IEEE80211_F_ASCAN) &&
341			    (ni->ni_chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) {
342				IEEE80211_SEND_MGMT(ic, ni,
343				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
344			}
345#else
346			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
347#endif
348			return 1;
349		}
350	} while (chan != ic->ic_bss->ni_chan);
351	ieee80211_end_scan(ic);
352	return 0;
353}
354
355void
356ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
357{
358	struct ieee80211_node *ni;
359
360	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
361		"%s: creating ibss\n", __func__);
362
363	/*
364	 * Create the station/neighbor table.  Note that for adhoc
365	 * mode we make the initial inactivity timer longer since
366	 * we create nodes only through discovery and they typically
367	 * are long-lived associations.
368	 */
369	if (ic->ic_opmode == IEEE80211_M_HOSTAP)
370		ic->ic_sta = ieee80211_node_table_alloc(ic,
371					"station", ic->ic_inact_init,
372					ieee80211_timeout_stations);
373	else
374		ic->ic_sta = ieee80211_node_table_alloc(ic,
375					"neighbor", ic->ic_inact_run,
376					ieee80211_timeout_stations);
377	if (ic->ic_sta == NULL) {
378		/*
379		 * Should remain in SCAN state and retry.
380		 */
381		/* XXX stat+msg */
382		return;
383	}
384
385	ni = ic->ic_bss;
386	IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr);
387	IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
388	ni->ni_esslen = ic->ic_des_esslen;
389	memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
390	ni->ni_rssi = 0;
391	ni->ni_rstamp = 0;
392	ni->ni_tstamp.tsf = 0;
393	ni->ni_intval = ic->ic_lintval;
394	ni->ni_capinfo = 0;
395	ni->ni_erp = 0;
396	if (ic->ic_flags & IEEE80211_F_PRIVACY)
397		ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
398	if (ic->ic_phytype == IEEE80211_T_FH) {
399		ni->ni_fhdwell = 200;	/* XXX */
400		ni->ni_fhindex = 1;
401	}
402	if (ic->ic_opmode == IEEE80211_M_IBSS) {
403		ic->ic_flags |= IEEE80211_F_SIBSS;
404		ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;	/* XXX */
405		ni->ni_bssid[0] |= 0x02;	/* local bit for IBSS */
406	}
407	/*
408	 * Fix the channel and related attributes.
409	 */
410	ieee80211_set_chan(ic, ni, chan);
411	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
412	/*
413	 * Do mode-specific rate setup.
414	 */
415	if (ic->ic_curmode == IEEE80211_MODE_11G) {
416		/*
417		 * Use a mixed 11b/11g rate set.
418		 */
419		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
420	} else if (ic->ic_curmode == IEEE80211_MODE_11B) {
421		/*
422		 * Force pure 11b rate set.
423		 */
424		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
425	}
426	/*
427	 * Set the erp state (mostly the slot time) to deal with
428	 * the auto-select case; this should be redundant if the
429	 * mode is locked.
430	 */
431	ieee80211_reset_erp(ic);
432	ieee80211_wme_initparams(ic);
433
434	ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
435}
436
437void
438ieee80211_reset_bss(struct ieee80211com *ic)
439{
440	struct ieee80211_node *ni, *obss;
441
442	ieee80211_node_table_reset(&ic->ic_scan);
443	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
444	KASSERT(ni != NULL, ("unable to setup inital BSS node"));
445	obss = ic->ic_bss;
446	ic->ic_bss = ieee80211_ref_node(ni);
447	if (obss != NULL)
448		ieee80211_free_node(obss);
449	if (ic->ic_sta != NULL) {
450		ieee80211_node_table_free(ic->ic_sta);
451		ic->ic_sta = NULL;
452	}
453}
454
455static int
456ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
457{
458        u_int8_t rate;
459        int fail;
460
461	fail = 0;
462	if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
463		fail |= 0x01;
464	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
465	    ni->ni_chan != ic->ic_des_chan)
466		fail |= 0x01;
467	if (ic->ic_opmode == IEEE80211_M_IBSS) {
468		if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
469			fail |= 0x02;
470	} else {
471		if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
472			fail |= 0x02;
473	}
474	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
475		if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
476			fail |= 0x04;
477	} else {
478		/* XXX does this mean privacy is supported or required? */
479		if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
480			fail |= 0x04;
481	}
482	rate = ieee80211_fix_rate(ic, ni,
483			IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
484	if (rate & IEEE80211_RATE_BASIC)
485		fail |= 0x08;
486	if (ic->ic_des_esslen != 0 &&
487	    (ni->ni_esslen != ic->ic_des_esslen ||
488	     memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
489		fail |= 0x10;
490	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
491	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
492		fail |= 0x20;
493#ifdef IEEE80211_DEBUG
494	if (ieee80211_msg_scan(ic)) {
495		printf(" %c %s", fail ? '-' : '+',
496		    ether_sprintf(ni->ni_macaddr));
497		printf(" %s%c", ether_sprintf(ni->ni_bssid),
498		    fail & 0x20 ? '!' : ' ');
499		printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
500			fail & 0x01 ? '!' : ' ');
501		printf(" %+4d", ni->ni_rssi);
502		printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
503		    fail & 0x08 ? '!' : ' ');
504		printf(" %4s%c",
505		    (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
506		    (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
507		    "????",
508		    fail & 0x02 ? '!' : ' ');
509		printf(" %3s%c ",
510		    (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
511		    "wep" : "no",
512		    fail & 0x04 ? '!' : ' ');
513		ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
514		printf("%s\n", fail & 0x10 ? "!" : "");
515	}
516#endif
517	return fail;
518}
519
520static __inline u_int8_t
521maxrate(const struct ieee80211_node *ni)
522{
523	const struct ieee80211_rateset *rs = &ni->ni_rates;
524	/* NB: assumes rate set is sorted (happens on frame receive) */
525	return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
526}
527
528/*
529 * Compare the capabilities of two nodes and decide which is
530 * more desirable (return >0 if a is considered better).  Note
531 * that we assume compatibility/usability has already been checked
532 * so we don't need to (e.g. validate whether privacy is supported).
533 * Used to select the best scan candidate for association in a BSS.
534 */
535static int
536ieee80211_node_compare(struct ieee80211com *ic,
537		       const struct ieee80211_node *a,
538		       const struct ieee80211_node *b)
539{
540	u_int8_t maxa, maxb;
541	u_int8_t rssia, rssib;
542
543	/* privacy support preferred */
544	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
545	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
546		return 1;
547	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
548	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
549		return -1;
550
551	rssia = ic->ic_node_getrssi(a);
552	rssib = ic->ic_node_getrssi(b);
553	if (abs(rssib - rssia) < 5) {
554		/* best/max rate preferred if signal level close enough XXX */
555		maxa = maxrate(a);
556		maxb = maxrate(b);
557		if (maxa != maxb)
558			return maxa - maxb;
559		/* XXX use freq for channel preference */
560		/* for now just prefer 5Ghz band to all other bands */
561		if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
562		   !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
563			return 1;
564		if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
565		     IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
566			return -1;
567	}
568	/* all things being equal, use signal level */
569	return rssia - rssib;
570}
571
572/*
573 * Mark an ongoing scan stopped.
574 */
575void
576ieee80211_cancel_scan(struct ieee80211com *ic)
577{
578
579	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
580		__func__,
581		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
582
583	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
584}
585
586/*
587 * Complete a scan of potential channels.
588 */
589void
590ieee80211_end_scan(struct ieee80211com *ic)
591{
592	struct ieee80211_node_table *nt = &ic->ic_scan;
593	struct ieee80211_node *ni, *selbs;
594
595	ieee80211_cancel_scan(ic);
596	ieee80211_notify_scan_done(ic);
597
598	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
599		u_int8_t maxrssi[IEEE80211_CHAN_MAX];	/* XXX off stack? */
600		int i, bestchan;
601		u_int8_t rssi;
602
603		/*
604		 * The passive scan to look for existing AP's completed,
605		 * select a channel to camp on.  Identify the channels
606		 * that already have one or more AP's and try to locate
607		 * an unnoccupied one.  If that fails, pick a channel that
608		 * looks to be quietest.
609		 */
610		memset(maxrssi, 0, sizeof(maxrssi));
611		IEEE80211_NODE_LOCK(nt);
612		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
613			rssi = ic->ic_node_getrssi(ni);
614			i = ieee80211_chan2ieee(ic, ni->ni_chan);
615			if (rssi > maxrssi[i])
616				maxrssi[i] = rssi;
617		}
618		IEEE80211_NODE_UNLOCK(nt);
619		/* XXX select channel more intelligently */
620		bestchan = -1;
621		for (i = 0; i < IEEE80211_CHAN_MAX; i++)
622			if (isset(ic->ic_chan_active, i)) {
623				/*
624				 * If the channel is unoccupied the max rssi
625				 * should be zero; just take it.  Otherwise
626				 * track the channel with the lowest rssi and
627				 * use that when all channels appear occupied.
628				 */
629				if (maxrssi[i] == 0) {
630					bestchan = i;
631					break;
632				}
633				if (maxrssi[i] < maxrssi[bestchan])
634					bestchan = i;
635			}
636		if (bestchan != -1) {
637			ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
638			return;
639		}
640		/* no suitable channel, should not happen */
641	}
642
643	/*
644	 * When manually sequencing the state machine; scan just once
645	 * regardless of whether we have a candidate or not.  The
646	 * controlling application is expected to setup state and
647	 * initiate an association.
648	 */
649	if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
650		return;
651	/*
652	 * Automatic sequencing; look for a candidate and
653	 * if found join the network.
654	 */
655	/* NB: unlocked read should be ok */
656	if (TAILQ_FIRST(&nt->nt_node) == NULL) {
657		IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
658			"%s: no scan candidate\n", __func__);
659  notfound:
660		if (ic->ic_opmode == IEEE80211_M_IBSS &&
661		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
662		    ic->ic_des_esslen != 0) {
663			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
664			return;
665		}
666		/*
667		 * Reset the list of channels to scan and start again.
668		 */
669		ieee80211_reset_scan(ic);
670		ic->ic_flags |= IEEE80211_F_SCAN;
671		ieee80211_next_scan(ic);
672		return;
673	}
674	selbs = NULL;
675	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
676	    "macaddr          bssid         chan  rssi rate flag  wep  essid");
677	IEEE80211_NODE_LOCK(nt);
678	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
679		if (ni->ni_fails) {
680			/*
681			 * The configuration of the access points may change
682			 * during my scan.  So delete the entry for the AP
683			 * and retry to associate if there is another beacon.
684			 */
685			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
686				"%s: skip scan candidate %s, fails %u\n",
687				__func__, ether_sprintf(ni->ni_macaddr),
688				ni->ni_fails);
689			ni->ni_fails++;
690#if 0
691			if (ni->ni_fails++ > 2)
692				ieee80211_free_node(ni);
693#endif
694			continue;
695		}
696		if (ieee80211_match_bss(ic, ni) == 0) {
697			if (selbs == NULL)
698				selbs = ni;
699			else if (ieee80211_node_compare(ic, ni, selbs) > 0)
700				selbs = ni;
701		}
702	}
703	if (selbs != NULL)		/* NB: grab ref while dropping lock */
704		(void) ieee80211_ref_node(selbs);
705	IEEE80211_NODE_UNLOCK(nt);
706	if (selbs == NULL)
707		goto notfound;
708	if (!ieee80211_sta_join(ic, selbs)) {
709		ieee80211_free_node(selbs);
710		goto notfound;
711	}
712}
713
714/*
715 * Handle 802.11 ad hoc network merge.  The
716 * convention, set by the Wireless Ethernet Compatibility Alliance
717 * (WECA), is that an 802.11 station will change its BSSID to match
718 * the "oldest" 802.11 ad hoc network, on the same channel, that
719 * has the station's desired SSID.  The "oldest" 802.11 network
720 * sends beacons with the greatest TSF timestamp.
721 *
722 * The caller is assumed to validate TSF's before attempting a merge.
723 *
724 * Return !0 if the BSSID changed, 0 otherwise.
725 */
726int
727ieee80211_ibss_merge(struct ieee80211com *ic, struct ieee80211_node *ni)
728{
729
730	if (ni == ic->ic_bss ||
731	    IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
732		/* unchanged, nothing to do */
733		return 0;
734	}
735	if (ieee80211_match_bss(ic, ni) != 0) {	/* capabilities mismatch */
736		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
737		    "%s: merge failed, capabilities mismatch\n", __func__);
738		ic->ic_stats.is_ibss_capmismatch++;
739		return 0;
740	}
741	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
742		"%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
743		ether_sprintf(ni->ni_bssid),
744		ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
745		ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
746		ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
747	);
748	return ieee80211_sta_join(ic, ni);
749}
750
751/*
752 * Join the specified IBSS/BSS network.  The node is assumed to
753 * be passed in with a held reference.
754 */
755int
756ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
757{
758	struct ieee80211_node *obss;
759
760	if (ic->ic_opmode == IEEE80211_M_IBSS) {
761		/*
762		 * Delete unusable rates; we've already checked
763		 * that the negotiated rate set is acceptable.
764		 */
765		ieee80211_fix_rate(ic, selbs, IEEE80211_F_DODEL);
766		/*
767		 * Create the neighbor table; it will already
768		 * exist if we are simply switching mastership.
769		 */
770		if (ic->ic_sta == NULL) {
771			ic->ic_sta = ieee80211_node_table_alloc(ic,
772					"neighbor", ic->ic_inact_run,
773					ieee80211_timeout_stations);
774			if (ic->ic_sta == NULL) {
775				/*
776				 * Should remain in SCAN state and retry.
777				 */
778				/* XXX stat+msg */
779				return 0;
780			}
781		}
782	}
783
784	/*
785	 * Committed to selbs, setup state.
786	 */
787	obss = ic->ic_bss;
788	ic->ic_bss = selbs;
789	if (obss != NULL)
790		ieee80211_free_node(obss);
791	/*
792	 * Set the erp state (mostly the slot time) to deal with
793	 * the auto-select case; this should be redundant if the
794	 * mode is locked.
795	 */
796	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
797	ieee80211_reset_erp(ic);
798	ieee80211_wme_initparams(ic);
799	if (ic->ic_opmode == IEEE80211_M_IBSS)
800		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
801	else
802		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
803	return 1;
804}
805
806/*
807 * Leave the specified IBSS/BSS network.  The node is assumed to
808 * be passed in with a held reference.
809 */
810void
811ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
812{
813	ic->ic_node_cleanup(ni);
814	ieee80211_notify_node_leave(ic, ni);
815}
816
817static struct ieee80211_node *
818node_alloc(struct ieee80211_node_table *nt)
819{
820	struct ieee80211_node *ni;
821
822	MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
823		M_80211_NODE, M_NOWAIT | M_ZERO);
824	return ni;
825}
826
827/*
828 * Reclaim any resources in a node and reset any critical
829 * state.  Typically nodes are free'd immediately after,
830 * but in some cases the storage may be reused so we need
831 * to insure consistent state (should probably fix that).
832 */
833static void
834node_cleanup(struct ieee80211_node *ni)
835{
836#define	N(a)	(sizeof(a)/sizeof(a[0]))
837	struct ieee80211com *ic = ni->ni_ic;
838	int i, qlen;
839
840	/* NB: preserve ni_table */
841	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
842		ic->ic_ps_sta--;
843		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
844		IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
845		    "[%s] power save mode off, %u sta's in ps mode\n",
846		    ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
847	}
848
849	/*
850	 * Drain power save queue and, if needed, clear TIM.
851	 */
852	IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
853	if (qlen != 0 && ic->ic_set_tim != NULL)
854		ic->ic_set_tim(ic, ni, 0);
855
856	ni->ni_associd = 0;
857	if (ni->ni_challenge != NULL) {
858		FREE(ni->ni_challenge, M_DEVBUF);
859		ni->ni_challenge = NULL;
860	}
861	/*
862	 * Preserve SSID, WPA, and WME ie's so the bss node is
863	 * reusable during a re-auth/re-assoc state transition.
864	 * If we remove these data they will not be recreated
865	 * because they come from a probe-response or beacon frame
866	 * which cannot be expected prior to the association-response.
867	 * This should not be an issue when operating in other modes
868	 * as stations leaving always go through a full state transition
869	 * which will rebuild this state.
870	 *
871	 * XXX does this leave us open to inheriting old state?
872	 */
873	for (i = 0; i < N(ni->ni_rxfrag); i++)
874		if (ni->ni_rxfrag[i] != NULL) {
875			m_freem(ni->ni_rxfrag[i]);
876			ni->ni_rxfrag[i] = NULL;
877		}
878	ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
879#undef N
880}
881
882static void
883node_free(struct ieee80211_node *ni)
884{
885	struct ieee80211com *ic = ni->ni_ic;
886
887	ic->ic_node_cleanup(ni);
888	if (ni->ni_wpa_ie != NULL)
889		FREE(ni->ni_wpa_ie, M_DEVBUF);
890	if (ni->ni_wme_ie != NULL)
891		FREE(ni->ni_wme_ie, M_DEVBUF);
892	IEEE80211_NODE_SAVEQ_DESTROY(ni);
893	FREE(ni, M_80211_NODE);
894}
895
896static u_int8_t
897node_getrssi(const struct ieee80211_node *ni)
898{
899	return ni->ni_rssi;
900}
901
902static void
903ieee80211_setup_node(struct ieee80211_node_table *nt,
904	struct ieee80211_node *ni, const u_int8_t *macaddr)
905{
906	struct ieee80211com *ic = nt->nt_ic;
907	int hash;
908
909	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
910		"%s %s in %s table\n", __func__,
911		ether_sprintf(macaddr), nt->nt_name);
912
913	IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
914	hash = IEEE80211_NODE_HASH(macaddr);
915	ieee80211_node_initref(ni);		/* mark referenced */
916	ni->ni_chan = IEEE80211_CHAN_ANYC;
917	ni->ni_authmode = IEEE80211_AUTH_OPEN;
918	ni->ni_txpower = ic->ic_txpowlimit;	/* max power */
919	ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
920	ni->ni_inact_reload = nt->nt_inact_init;
921	ni->ni_inact = ni->ni_inact_reload;
922	IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
923
924	IEEE80211_NODE_LOCK(nt);
925	TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
926	LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
927	ni->ni_table = nt;
928	ni->ni_ic = ic;
929	IEEE80211_NODE_UNLOCK(nt);
930}
931
932struct ieee80211_node *
933ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
934{
935	struct ieee80211com *ic = nt->nt_ic;
936	struct ieee80211_node *ni;
937
938	ni = ic->ic_node_alloc(nt);
939	if (ni != NULL)
940		ieee80211_setup_node(nt, ni, macaddr);
941	else
942		ic->ic_stats.is_rx_nodealloc++;
943	return ni;
944}
945
946struct ieee80211_node *
947ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
948{
949	struct ieee80211com *ic = nt->nt_ic;
950	struct ieee80211_node *ni;
951
952	ni = ic->ic_node_alloc(nt);
953	if (ni != NULL) {
954		ieee80211_setup_node(nt, ni, macaddr);
955		/*
956		 * Inherit from ic_bss.
957		 */
958		ni->ni_authmode = ic->ic_bss->ni_authmode;
959		ni->ni_txpower = ic->ic_bss->ni_txpower;
960		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
961		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
962		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
963		ni->ni_rsn = ic->ic_bss->ni_rsn;
964	} else
965		ic->ic_stats.is_rx_nodealloc++;
966	return ni;
967}
968
969static struct ieee80211_node *
970#ifdef IEEE80211_DEBUG_REFCNT
971_ieee80211_find_node_debug(struct ieee80211_node_table *nt,
972	const u_int8_t *macaddr, const char *func, int line)
973#else
974_ieee80211_find_node(struct ieee80211_node_table *nt,
975	const u_int8_t *macaddr)
976#endif
977{
978	struct ieee80211_node *ni;
979	int hash;
980
981	IEEE80211_NODE_LOCK_ASSERT(nt);
982
983	hash = IEEE80211_NODE_HASH(macaddr);
984	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
985		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
986			ieee80211_ref_node(ni);	/* mark referenced */
987#ifdef IEEE80211_DEBUG_REFCNT
988			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
989			    "%s (%s:%u) %s refcnt %d\n", __func__, func, line,
990			     ether_sprintf(ni->ni_macaddr),
991			     ieee80211_node_refcnt(ni));
992#endif
993			return ni;
994		}
995	}
996	return NULL;
997}
998#ifdef IEEE80211_DEBUG_REFCNT
999#define	_ieee80211_find_node(nt, mac) \
1000	_ieee80211_find_node_debug(nt, mac, func, line)
1001#endif
1002
1003struct ieee80211_node *
1004#ifdef IEEE80211_DEBUG_REFCNT
1005ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1006	const u_int8_t *macaddr, const char *func, int line)
1007#else
1008ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1009#endif
1010{
1011	struct ieee80211_node *ni;
1012
1013	IEEE80211_NODE_LOCK(nt);
1014	ni = _ieee80211_find_node(nt, macaddr);
1015	IEEE80211_NODE_UNLOCK(nt);
1016	return ni;
1017}
1018
1019/*
1020 * Fake up a node; this handles node discovery in adhoc mode.
1021 * Note that for the driver's benefit we we treat this like
1022 * an association so the driver has an opportunity to setup
1023 * it's private state.
1024 */
1025struct ieee80211_node *
1026ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
1027	const u_int8_t macaddr[IEEE80211_ADDR_LEN])
1028{
1029	struct ieee80211com *ic = nt->nt_ic;
1030	struct ieee80211_node *ni;
1031
1032	ni = ieee80211_dup_bss(nt, macaddr);
1033	if (ni != NULL) {
1034		/* XXX no rate negotiation; just dup */
1035		ni->ni_rates = ic->ic_bss->ni_rates;
1036		if (ic->ic_newassoc != NULL)
1037			ic->ic_newassoc(ic, ni, 1);
1038		/* XXX not right for 802.1x/WPA */
1039		ieee80211_node_authorize(ic, ni);
1040		ieee80211_ref_node(ni);		/* hold reference */
1041	}
1042	return ni;
1043}
1044
1045/*
1046 * Locate the node for sender, track state, and then pass the
1047 * (referenced) node up to the 802.11 layer for its use.  We
1048 * are required to pass some node so we fall back to ic_bss
1049 * when this frame is from an unknown sender.  The 802.11 layer
1050 * knows this means the sender wasn't in the node table and
1051 * acts accordingly.
1052 */
1053struct ieee80211_node *
1054#ifdef IEEE80211_DEBUG_REFCNT
1055ieee80211_find_rxnode_debug(struct ieee80211com *ic,
1056	const struct ieee80211_frame_min *wh, const char *func, int line)
1057#else
1058ieee80211_find_rxnode(struct ieee80211com *ic,
1059	const struct ieee80211_frame_min *wh)
1060#endif
1061{
1062#define	IS_CTL(wh) \
1063	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1064#define	IS_PSPOLL(wh) \
1065	((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
1066	struct ieee80211_node_table *nt;
1067	struct ieee80211_node *ni;
1068
1069	/* XXX may want scanned nodes in the neighbor table for adhoc */
1070	if (ic->ic_opmode == IEEE80211_M_STA ||
1071	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1072	    (ic->ic_flags & IEEE80211_F_SCAN))
1073		nt = &ic->ic_scan;
1074	else
1075		nt = ic->ic_sta;
1076	/* XXX check ic_bss first in station mode */
1077	/* XXX 4-address frames? */
1078	IEEE80211_NODE_LOCK(nt);
1079	if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1080		ni = _ieee80211_find_node(nt, wh->i_addr1);
1081	else
1082		ni = _ieee80211_find_node(nt, wh->i_addr2);
1083	IEEE80211_NODE_UNLOCK(nt);
1084
1085	return (ni != NULL ? ni : ieee80211_ref_node(ic->ic_bss));
1086#undef IS_PSPOLL
1087#undef IS_CTL
1088}
1089
1090/*
1091 * Return a reference to the appropriate node for sending
1092 * a data frame.  This handles node discovery in adhoc networks.
1093 */
1094struct ieee80211_node *
1095#ifdef IEEE80211_DEBUG_REFCNT
1096ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
1097	const char *func, int line)
1098#else
1099ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
1100#endif
1101{
1102	struct ieee80211_node_table *nt = ic->ic_sta;
1103	struct ieee80211_node *ni;
1104
1105	/*
1106	 * The destination address should be in the node table
1107	 * unless we are operating in station mode or this is a
1108	 * multicast/broadcast frame.
1109	 */
1110	if (nt == NULL || IEEE80211_IS_MULTICAST(macaddr))
1111		return ieee80211_ref_node(ic->ic_bss);
1112
1113	/* XXX can't hold lock across dup_bss 'cuz of recursive locking */
1114	IEEE80211_NODE_LOCK(nt);
1115	ni = _ieee80211_find_node(nt, macaddr);
1116	IEEE80211_NODE_UNLOCK(nt);
1117
1118	if (ni == NULL) {
1119		if (ic->ic_opmode == IEEE80211_M_IBSS ||
1120		    ic->ic_opmode == IEEE80211_M_AHDEMO)
1121			ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
1122		else {
1123			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
1124				"[%s] no node, discard frame (%s)\n",
1125				ether_sprintf(macaddr), __func__);
1126			ic->ic_stats.is_tx_nonode++;
1127		}
1128	}
1129	return ni;
1130}
1131
1132/*
1133 * Like find but search based on the channel too.
1134 */
1135struct ieee80211_node *
1136#ifdef IEEE80211_DEBUG_REFCNT
1137ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
1138	const u_int8_t *macaddr, struct ieee80211_channel *chan,
1139	const char *func, int line)
1140#else
1141ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
1142	const u_int8_t *macaddr, struct ieee80211_channel *chan)
1143#endif
1144{
1145	struct ieee80211_node *ni;
1146	int hash;
1147
1148	hash = IEEE80211_NODE_HASH(macaddr);
1149	IEEE80211_NODE_LOCK(nt);
1150	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1151		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1152		    ni->ni_chan == chan) {
1153			ieee80211_ref_node(ni);		/* mark referenced */
1154			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1155#ifdef IEEE80211_DEBUG_REFCNT
1156			    "%s (%s:%u) %s refcnt %d\n", __func__, func, line,
1157#else
1158			    "%s %s refcnt %d\n", __func__,
1159#endif
1160			     ether_sprintf(ni->ni_macaddr),
1161			     ieee80211_node_refcnt(ni));
1162			break;
1163		}
1164	}
1165	IEEE80211_NODE_UNLOCK(nt);
1166	return ni;
1167}
1168
1169/*
1170 * Like find but search based on the ssid too.
1171 */
1172struct ieee80211_node *
1173#ifdef IEEE80211_DEBUG_REFCNT
1174ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
1175	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
1176	const char *func, int line)
1177#else
1178ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
1179	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
1180#endif
1181{
1182	struct ieee80211com *ic = nt->nt_ic;
1183	struct ieee80211_node *ni;
1184	int hash;
1185
1186	hash = IEEE80211_NODE_HASH(macaddr);
1187	IEEE80211_NODE_LOCK(nt);
1188	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1189		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1190		    ni->ni_esslen == ic->ic_des_esslen &&
1191		    memcmp(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen) == 0) {
1192			ieee80211_ref_node(ni);		/* mark referenced */
1193			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1194#ifdef IEEE80211_DEBUG_REFCNT
1195			    "%s (%s:%u) %s refcnt %d\n", __func__, func, line,
1196#else
1197			    "%s %s refcnt %d\n", __func__,
1198#endif
1199			     ether_sprintf(ni->ni_macaddr),
1200			     ieee80211_node_refcnt(ni));
1201			break;
1202		}
1203	}
1204	IEEE80211_NODE_UNLOCK(nt);
1205	return ni;
1206}
1207
1208
1209static void
1210_ieee80211_free_node(struct ieee80211_node *ni)
1211{
1212	struct ieee80211com *ic = ni->ni_ic;
1213	struct ieee80211_node_table *nt = ni->ni_table;
1214
1215	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1216		"%s %s in %s table\n", __func__, ether_sprintf(ni->ni_macaddr),
1217		nt != NULL ? nt->nt_name : "<gone>");
1218
1219	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1220	if (nt != NULL) {
1221		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1222		LIST_REMOVE(ni, ni_hash);
1223	}
1224	ic->ic_node_free(ni);
1225}
1226
1227void
1228#ifdef IEEE80211_DEBUG_REFCNT
1229ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
1230#else
1231ieee80211_free_node(struct ieee80211_node *ni)
1232#endif
1233{
1234	struct ieee80211_node_table *nt = ni->ni_table;
1235
1236#ifdef IEEE80211_DEBUG_REFCNT
1237	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1238		"%s (%s:%u) %s refcnt %d\n", __func__, func, line,
1239		 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
1240#endif
1241	if (ieee80211_node_dectestref(ni)) {
1242		/*
1243		 * Beware; if the node is marked gone then it's already
1244		 * been removed from the table and we cannot assume the
1245		 * table still exists.  Regardless, there's no need to lock
1246		 * the table.
1247		 */
1248		if (ni->ni_table != NULL) {
1249			IEEE80211_NODE_LOCK(nt);
1250			_ieee80211_free_node(ni);
1251			IEEE80211_NODE_UNLOCK(nt);
1252		} else
1253			_ieee80211_free_node(ni);
1254	}
1255}
1256
1257/*
1258 * Reclaim a node.  If this is the last reference count then
1259 * do the normal free work.  Otherwise remove it from the node
1260 * table and mark it gone by clearing the back-reference.
1261 */
1262static void
1263node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1264{
1265
1266	if (!ieee80211_node_dectestref(ni)) {
1267		/*
1268		 * Other references are present, just remove the
1269		 * node from the table so it cannot be found.  When
1270		 * the references are dropped storage will be
1271		 * reclaimed.  This normally only happens for ic_bss.
1272		 */
1273		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1274		LIST_REMOVE(ni, ni_hash);
1275		ni->ni_table = NULL;		/* clear reference */
1276	} else
1277		_ieee80211_free_node(ni);
1278}
1279
1280static void
1281ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
1282{
1283	struct ieee80211com *ic = nt->nt_ic;
1284	struct ieee80211_node *ni;
1285
1286	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1287		"%s: free all nodes in %s table\n", __func__, nt->nt_name);
1288
1289	while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
1290		if (ni->ni_associd != 0) {
1291			if (ic->ic_auth->ia_node_leave != NULL)
1292				ic->ic_auth->ia_node_leave(ic, ni);
1293			IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1294		}
1295		node_reclaim(nt, ni);
1296	}
1297	ieee80211_reset_erp(ic);
1298}
1299
1300static void
1301ieee80211_free_allnodes(struct ieee80211_node_table *nt)
1302{
1303
1304	IEEE80211_NODE_LOCK(nt);
1305	ieee80211_free_allnodes_locked(nt);
1306	IEEE80211_NODE_UNLOCK(nt);
1307}
1308
1309/*
1310 * Timeout entries in the scan cache.
1311 */
1312static void
1313ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
1314{
1315	struct ieee80211com *ic = nt->nt_ic;
1316	struct ieee80211_node *ni, *tni;
1317
1318	IEEE80211_NODE_LOCK(nt);
1319	ni = ic->ic_bss;
1320	/* XXX belongs elsewhere */
1321	if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
1322		m_freem(ni->ni_rxfrag[0]);
1323		ni->ni_rxfrag[0] = NULL;
1324	}
1325	TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
1326		if (ni->ni_inact && --ni->ni_inact == 0) {
1327			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1328			    "[%s] scan candidate purged from cache "
1329			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1330			    ieee80211_node_refcnt(ni)-1);
1331			node_reclaim(nt, ni);
1332		}
1333	}
1334	IEEE80211_NODE_UNLOCK(nt);
1335
1336	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1337}
1338
1339/*
1340 * Timeout inactive stations and do related housekeeping.
1341 * Note that we cannot hold the node lock while sending a
1342 * frame as this would lead to a LOR.  Instead we use a
1343 * generation number to mark nodes that we've scanned and
1344 * drop the lock and restart a scan if we have to time out
1345 * a node.  Since we are single-threaded by virtue of
1346 * controlling the inactivity timer we can be sure this will
1347 * process each node only once.
1348 */
1349static void
1350ieee80211_timeout_stations(struct ieee80211_node_table *nt)
1351{
1352	struct ieee80211com *ic = nt->nt_ic;
1353	struct ieee80211_node *ni;
1354	u_int gen;
1355
1356	IEEE80211_SCAN_LOCK(nt);
1357	gen = nt->nt_scangen++;
1358	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1359		"%s: sta scangen %u\n", __func__, gen);
1360restart:
1361	IEEE80211_NODE_LOCK(nt);
1362	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1363		if (ni->ni_scangen == gen)	/* previously handled */
1364			continue;
1365		ni->ni_scangen = gen;
1366		/*
1367		 * Free fragment if not needed anymore
1368		 * (last fragment older than 1s).
1369		 * XXX doesn't belong here
1370		 */
1371		if (ni->ni_rxfrag[0] != NULL &&
1372		    ticks > ni->ni_rxfragstamp + hz) {
1373			m_freem(ni->ni_rxfrag[0]);
1374			ni->ni_rxfrag[0] = NULL;
1375		}
1376		ni->ni_inact--;
1377		if (ni->ni_associd != 0) {
1378			/*
1379			 * Age frames on the power save queue. The
1380			 * aging interval is 4 times the listen
1381			 * interval specified by the station.  This
1382			 * number is factored into the age calculations
1383			 * when the frame is placed on the queue.  We
1384			 * store ages as time differences we can check
1385			 * and/or adjust only the head of the list.
1386			 */
1387			if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
1388				struct mbuf *m;
1389				int discard = 0;
1390
1391				IEEE80211_NODE_SAVEQ_LOCK(ni);
1392				while (IF_POLL(&ni->ni_savedq, m) != NULL &&
1393				     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
1394IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
1395					_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
1396					m_freem(m);
1397					discard++;
1398				}
1399				if (m != NULL)
1400					M_AGE_SUB(m, IEEE80211_INACT_WAIT);
1401				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1402
1403				if (discard != 0) {
1404					IEEE80211_DPRINTF(ic,
1405					    IEEE80211_MSG_POWER,
1406					    "[%s] discard %u frames for age\n",
1407					    ether_sprintf(ni->ni_macaddr),
1408					    discard);
1409					IEEE80211_NODE_STAT_ADD(ni,
1410						ps_discard, discard);
1411					if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
1412						ic->ic_set_tim(ic, ni, 0);
1413				}
1414			}
1415			/*
1416			 * Probe the station before time it out.  We
1417			 * send a null data frame which may not be
1418			 * universally supported by drivers (need it
1419			 * for ps-poll support so it should be...).
1420			 */
1421			if (0 < ni->ni_inact &&
1422			    ni->ni_inact <= ic->ic_inact_probe) {
1423				IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1424				    "[%s] probe station due to inactivity\n",
1425				    ether_sprintf(ni->ni_macaddr));
1426				IEEE80211_NODE_UNLOCK(nt);
1427				ieee80211_send_nulldata(ic, ni);
1428				/* XXX stat? */
1429				goto restart;
1430			}
1431		}
1432		if (ni->ni_inact <= 0) {
1433			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1434			    "[%s] station timed out due to inactivity "
1435			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1436			    ieee80211_node_refcnt(ni));
1437			/*
1438			 * Send a deauthenticate frame and drop the station.
1439			 * This is somewhat complicated due to reference counts
1440			 * and locking.  At this point a station will typically
1441			 * have a reference count of 1.  ieee80211_node_leave
1442			 * will do a "free" of the node which will drop the
1443			 * reference count.  But in the meantime a reference
1444			 * wil be held by the deauth frame.  The actual reclaim
1445			 * of the node will happen either after the tx is
1446			 * completed or by ieee80211_node_leave.
1447			 *
1448			 * Separately we must drop the node lock before sending
1449			 * in case the driver takes a lock, as this will result
1450			 * in  LOR between the node lock and the driver lock.
1451			 */
1452			IEEE80211_NODE_UNLOCK(nt);
1453			if (ni->ni_associd != 0) {
1454				IEEE80211_SEND_MGMT(ic, ni,
1455				    IEEE80211_FC0_SUBTYPE_DEAUTH,
1456				    IEEE80211_REASON_AUTH_EXPIRE);
1457			}
1458			ieee80211_node_leave(ic, ni);
1459			ic->ic_stats.is_node_timeout++;
1460			goto restart;
1461		}
1462	}
1463	IEEE80211_NODE_UNLOCK(nt);
1464
1465	IEEE80211_SCAN_UNLOCK(nt);
1466
1467	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1468}
1469
1470void
1471ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
1472{
1473	struct ieee80211_node *ni;
1474	u_int gen;
1475
1476	IEEE80211_SCAN_LOCK(nt);
1477	gen = nt->nt_scangen++;
1478
1479	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1480		"%s: sta scangen %u\n", __func__, gen);
1481restart:
1482	IEEE80211_NODE_LOCK(nt);
1483	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1484		if (ni->ni_scangen != gen) {
1485			ni->ni_scangen = gen;
1486			(void) ieee80211_ref_node(ni);
1487			IEEE80211_NODE_UNLOCK(nt);
1488			(*f)(arg, ni);
1489			ieee80211_free_node(ni);
1490			goto restart;
1491		}
1492	}
1493	IEEE80211_NODE_UNLOCK(nt);
1494
1495	IEEE80211_SCAN_UNLOCK(nt);
1496}
1497
1498void
1499ieee80211_dump_node(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1500{
1501	printf("0x%p: mac %s refcnt %d\n", ni,
1502		ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
1503	printf("\tscangen %u authmode %u flags 0x%x\n",
1504		ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
1505	printf("\tassocid 0x%x txpower %u vlan %u\n",
1506		ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
1507	printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
1508		ni->ni_txseqs[0],
1509		ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
1510		ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
1511		ni->ni_rxfragstamp);
1512	printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
1513		ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
1514	printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
1515		ether_sprintf(ni->ni_bssid),
1516		ni->ni_esslen, ni->ni_essid,
1517		ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
1518	printf("\tfails %u inact %u txrate %u\n",
1519		ni->ni_fails, ni->ni_inact, ni->ni_txrate);
1520}
1521
1522void
1523ieee80211_dump_nodes(struct ieee80211_node_table *nt)
1524{
1525	ieee80211_iterate_nodes(nt,
1526		(ieee80211_iter_func *) ieee80211_dump_node, nt);
1527}
1528
1529/*
1530 * Handle a station joining an 11g network.
1531 */
1532static void
1533ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1534{
1535
1536	/*
1537	 * Station isn't capable of short slot time.  Bump
1538	 * the count of long slot time stations and disable
1539	 * use of short slot time.  Note that the actual switch
1540	 * over to long slot time use may not occur until the
1541	 * next beacon transmission (per sec. 7.3.1.4 of 11g).
1542	 */
1543	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1544		ic->ic_longslotsta++;
1545		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1546		    "[%s] station needs long slot time, count %d\n",
1547		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1548		/* XXX vap's w/ conflicting needs won't work */
1549		ieee80211_set_shortslottime(ic, 0);
1550	}
1551	/*
1552	 * If the new station is not an ERP station
1553	 * then bump the counter and enable protection
1554	 * if configured.
1555	 */
1556	if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
1557		ic->ic_nonerpsta++;
1558		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1559		    "[%s] station is !ERP, %d non-ERP stations associated\n",
1560		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1561		/*
1562		 * If protection is configured, enable it.
1563		 */
1564		if (ic->ic_protmode != IEEE80211_PROT_NONE) {
1565			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1566			    "%s: enable use of protection\n", __func__);
1567			ic->ic_flags |= IEEE80211_F_USEPROT;
1568		}
1569		/*
1570		 * If station does not support short preamble
1571		 * then we must enable use of Barker preamble.
1572		 */
1573		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
1574			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1575			    "[%s] station needs long preamble\n",
1576			    ether_sprintf(ni->ni_macaddr));
1577			ic->ic_flags |= IEEE80211_F_USEBARKER;
1578			ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
1579		}
1580	} else
1581		ni->ni_flags |= IEEE80211_NODE_ERP;
1582}
1583
1584void
1585ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
1586{
1587	int newassoc;
1588
1589	if (ni->ni_associd == 0) {
1590		u_int16_t aid;
1591
1592		/*
1593		 * It would be good to search the bitmap
1594		 * more efficiently, but this will do for now.
1595		 */
1596		for (aid = 1; aid < ic->ic_max_aid; aid++) {
1597			if (!IEEE80211_AID_ISSET(aid,
1598			    ic->ic_aid_bitmap))
1599				break;
1600		}
1601		if (aid >= ic->ic_max_aid) {
1602			IEEE80211_SEND_MGMT(ic, ni, resp,
1603			    IEEE80211_REASON_ASSOC_TOOMANY);
1604			ieee80211_node_leave(ic, ni);
1605			return;
1606		}
1607		ni->ni_associd = aid | 0xc000;
1608		IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
1609		ic->ic_sta_assoc++;
1610		newassoc = 1;
1611		if (ic->ic_curmode == IEEE80211_MODE_11G ||
1612		    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1613			ieee80211_node_join_11g(ic, ni);
1614	} else
1615		newassoc = 0;
1616
1617	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1618	    "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
1619	    ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
1620	    IEEE80211_NODE_AID(ni),
1621	    ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
1622	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
1623	    ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
1624	    ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
1625	);
1626
1627	/* give driver a chance to setup state like ni_txrate */
1628	if (ic->ic_newassoc != NULL)
1629		ic->ic_newassoc(ic, ni, newassoc);
1630	ni->ni_inact_reload = ic->ic_inact_auth;
1631	ni->ni_inact = ni->ni_inact_reload;
1632	IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
1633	/* tell the authenticator about new station */
1634	if (ic->ic_auth->ia_node_join != NULL)
1635		ic->ic_auth->ia_node_join(ic, ni);
1636	ieee80211_notify_node_join(ic, ni, newassoc);
1637}
1638
1639/*
1640 * Handle a station leaving an 11g network.
1641 */
1642static void
1643ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1644{
1645
1646	KASSERT(ic->ic_curmode == IEEE80211_MODE_11G ||
1647		ic->ic_curmode == IEEE80211_MODE_TURBO_G,
1648		("not in 11g, curmode %x", ic->ic_curmode));
1649
1650	/*
1651	 * If a long slot station do the slot time bookkeeping.
1652	 */
1653	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1654		KASSERT(ic->ic_longslotsta > 0,
1655		    ("bogus long slot station count %d", ic->ic_longslotsta));
1656		ic->ic_longslotsta--;
1657		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1658		    "[%s] long slot time station leaves, count now %d\n",
1659		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1660		if (ic->ic_longslotsta == 0) {
1661			/*
1662			 * Re-enable use of short slot time if supported
1663			 * and not operating in IBSS mode (per spec).
1664			 */
1665			if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
1666			    ic->ic_opmode != IEEE80211_M_IBSS) {
1667				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1668				    "%s: re-enable use of short slot time\n",
1669				    __func__);
1670				ieee80211_set_shortslottime(ic, 1);
1671			}
1672		}
1673	}
1674	/*
1675	 * If a non-ERP station do the protection-related bookkeeping.
1676	 */
1677	if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
1678		KASSERT(ic->ic_nonerpsta > 0,
1679		    ("bogus non-ERP station count %d", ic->ic_nonerpsta));
1680		ic->ic_nonerpsta--;
1681		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1682		    "[%s] non-ERP station leaves, count now %d\n",
1683		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1684		if (ic->ic_nonerpsta == 0) {
1685			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1686				"%s: disable use of protection\n", __func__);
1687			ic->ic_flags &= ~IEEE80211_F_USEPROT;
1688			/* XXX verify mode? */
1689			if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
1690				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1691				    "%s: re-enable use of short preamble\n",
1692				    __func__);
1693				ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
1694				ic->ic_flags &= ~IEEE80211_F_USEBARKER;
1695			}
1696		}
1697	}
1698}
1699
1700/*
1701 * Handle bookkeeping for station deauthentication/disassociation
1702 * when operating as an ap.
1703 */
1704void
1705ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
1706{
1707
1708	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1709	    "[%s] station with aid %d leaves\n",
1710	    ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
1711
1712	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1713		ic->ic_opmode == IEEE80211_M_IBSS ||
1714		ic->ic_opmode == IEEE80211_M_AHDEMO,
1715		("unexpected operating mode %u", ic->ic_opmode));
1716	/*
1717	 * If node wasn't previously associated all
1718	 * we need to do is reclaim the reference.
1719	 */
1720	/* XXX ibss mode bypasses 11g and notification */
1721	if (ni->ni_associd == 0)
1722		goto done;
1723	/*
1724	 * Tell the authenticator the station is leaving.
1725	 * Note that we must do this before yanking the
1726	 * association id as the authenticator uses the
1727	 * associd to locate it's state block.
1728	 */
1729	if (ic->ic_auth->ia_node_leave != NULL)
1730		ic->ic_auth->ia_node_leave(ic, ni);
1731	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1732	ni->ni_associd = 0;
1733	ic->ic_sta_assoc--;
1734
1735	if (ic->ic_curmode == IEEE80211_MODE_11G ||
1736	    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1737		ieee80211_node_leave_11g(ic, ni);
1738	/*
1739	 * Cleanup station state.  In particular clear various
1740	 * state that might otherwise be reused if the node
1741	 * is reused before the reference count goes to zero
1742	 * (and memory is reclaimed).
1743	 */
1744	ieee80211_sta_leave(ic, ni);
1745done:
1746	ni->ni_inact_reload = ic->ic_inact_init;	/* just in case */
1747	ieee80211_free_node(ni);
1748}
1749
1750u_int8_t
1751ieee80211_getrssi(struct ieee80211com *ic)
1752{
1753#define	NZ(x)	((x) == 0 ? 1 : (x))
1754	struct ieee80211_node_table *nt = ic->ic_sta;
1755	u_int32_t rssi_samples, rssi_total;
1756	struct ieee80211_node *ni;
1757
1758	rssi_total = 0;
1759	rssi_samples = 0;
1760	switch (ic->ic_opmode) {
1761	case IEEE80211_M_IBSS:		/* average of all ibss neighbors */
1762		nt = ic->ic_sta;
1763		if (nt == NULL)
1764			break;
1765		/* XXX locking */
1766		TAILQ_FOREACH(ni, &ic->ic_sta->nt_node, ni_list)
1767			if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
1768				rssi_samples++;
1769				rssi_total += ic->ic_node_getrssi(ni);
1770			}
1771		break;
1772	case IEEE80211_M_AHDEMO:	/* average of all neighbors */
1773		nt = ic->ic_sta;
1774		if (nt == NULL)
1775			break;
1776		/* XXX locking */
1777		TAILQ_FOREACH(ni, &ic->ic_sta->nt_node, ni_list) {
1778			rssi_samples++;
1779			rssi_total += ic->ic_node_getrssi(ni);
1780		}
1781		break;
1782	case IEEE80211_M_HOSTAP:	/* average of all associated stations */
1783		nt = ic->ic_sta;
1784		if (nt == NULL)
1785			break;
1786		/* XXX locking */
1787		TAILQ_FOREACH(ni, &ic->ic_sta->nt_node, ni_list)
1788			if (IEEE80211_AID(ni->ni_associd) != 0) {
1789				rssi_samples++;
1790				rssi_total += ic->ic_node_getrssi(ni);
1791			}
1792		break;
1793	case IEEE80211_M_MONITOR:	/* XXX */
1794	case IEEE80211_M_STA:		/* use stats from associated ap */
1795	default:
1796		if (ic->ic_bss != NULL)
1797			rssi_total = ic->ic_node_getrssi(ic->ic_bss);
1798		rssi_samples = 1;
1799		break;
1800	}
1801	return rssi_total / NZ(rssi_samples);
1802#undef NZ
1803}
1804
1805/*
1806 * Indicate whether there are frames queued for a station in power-save mode.
1807 */
1808static void
1809ieee80211_set_tim(struct ieee80211com *ic, struct ieee80211_node *ni, int set)
1810{
1811	u_int16_t aid;
1812
1813	KASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1814		ic->ic_opmode == IEEE80211_M_IBSS,
1815		("operating mode %u", ic->ic_opmode));
1816
1817	aid = IEEE80211_AID(ni->ni_associd);
1818	KASSERT(aid < ic->ic_max_aid,
1819		("bogus aid %u, max %u", aid, ic->ic_max_aid));
1820
1821	IEEE80211_BEACON_LOCK(ic);
1822	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
1823		if (set) {
1824			setbit(ic->ic_tim_bitmap, aid);
1825			ic->ic_ps_pending++;
1826		} else {
1827			clrbit(ic->ic_tim_bitmap, aid);
1828			ic->ic_ps_pending--;
1829		}
1830		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
1831	}
1832	IEEE80211_BEACON_UNLOCK(ic);
1833}
1834
1835/*
1836 * Node table support.
1837 */
1838
1839static void
1840ieee80211_node_table_init(struct ieee80211com *ic,
1841	struct ieee80211_node_table *nt,
1842	const char *name, int inact,
1843	void (*timeout)(struct ieee80211_node_table *))
1844{
1845
1846	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1847		"%s %s table, inact %u\n", __func__, name, inact);
1848
1849	nt->nt_ic = ic;
1850	/* XXX need unit */
1851	IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1852	IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1853	TAILQ_INIT(&nt->nt_node);
1854	nt->nt_name = name;
1855	nt->nt_scangen = 1;
1856	nt->nt_inact_init = inact;
1857	nt->nt_timeout = timeout;
1858}
1859
1860static struct ieee80211_node_table *
1861ieee80211_node_table_alloc(struct ieee80211com *ic,
1862	const char *name, int inact,
1863	void (*timeout)(struct ieee80211_node_table *))
1864{
1865	struct ieee80211_node_table *nt;
1866
1867	MALLOC(nt, struct ieee80211_node_table *,
1868		sizeof(struct ieee80211_node_table),
1869		M_DEVBUF, M_NOWAIT | M_ZERO);
1870	if (nt == NULL) {
1871		printf("%s: no memory node table!\n", __func__);
1872		return NULL;
1873	}
1874	ieee80211_node_table_init(ic, nt, name, inact, timeout);
1875	return nt;
1876}
1877
1878void
1879ieee80211_node_table_reset(struct ieee80211_node_table *nt)
1880{
1881
1882	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1883		"%s %s table\n", __func__, nt->nt_name);
1884
1885	IEEE80211_NODE_LOCK(nt);
1886	nt->nt_inact_timer = 0;
1887	ieee80211_free_allnodes_locked(nt);
1888	IEEE80211_NODE_UNLOCK(nt);
1889}
1890
1891static void
1892ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
1893{
1894
1895	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1896		"%s %s table\n", __func__, nt->nt_name);
1897
1898	ieee80211_free_allnodes_locked(nt);
1899	IEEE80211_SCAN_LOCK_DESTROY(nt);
1900	IEEE80211_NODE_LOCK_DESTROY(nt);
1901}
1902
1903/*
1904 * NB: public for use in ieee80211_proto.c
1905 */
1906void
1907ieee80211_node_table_free(struct ieee80211_node_table *nt)
1908{
1909
1910	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1911		"%s %s table\n", __func__, nt->nt_name);
1912
1913	IEEE80211_NODE_LOCK(nt);
1914	nt->nt_inact_timer = 0;
1915	ieee80211_node_table_cleanup(nt);
1916	FREE(nt, M_DEVBUF);
1917}
1918