xref: /netbsd-src/sys/net80211/ieee80211_node.c (revision 9c1da17e908379b8a470f1117a6395bd6a0ca559)
1 /*	$NetBSD: ieee80211_node.c,v 1.43 2005/07/26 23:07:53 dyoung Exp $	*/
2 /*-
3  * Copyright (c) 2001 Atsushi Onoe
4  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * Alternatively, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2 as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifdef __FreeBSD__
36 __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_node.c,v 1.48 2005/07/06 01:51:44 sam Exp $");
37 #endif
38 #ifdef __NetBSD__
39 __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.43 2005/07/26 23:07:53 dyoung Exp $");
40 #endif
41 
42 #include "opt_inet.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/mbuf.h>
47 #include <sys/malloc.h>
48 #include <sys/kernel.h>
49 
50 #include <sys/socket.h>
51 #include <sys/sockio.h>
52 #include <sys/endian.h>
53 #include <sys/errno.h>
54 #include <sys/proc.h>
55 #include <sys/sysctl.h>
56 
57 #include <net/if.h>
58 #include <net/if_media.h>
59 #include <net/if_arp.h>
60 #include <net/if_ether.h>
61 #include <net/if_llc.h>
62 
63 #include <net80211/ieee80211_netbsd.h>
64 #include <net80211/ieee80211_var.h>
65 
66 #include <net/bpf.h>
67 
68 #ifdef INET
69 #include <netinet/in.h>
70 #include <net/if_ether.h>
71 #endif
72 
73 /*
74  * Association id's are managed with a bit vector.
75  */
76 #define	IEEE80211_AID_SET(b, w) \
77 	((w)[IEEE80211_AID(b) / 32] |= (1 << (IEEE80211_AID(b) % 32)))
78 #define	IEEE80211_AID_CLR(b, w) \
79 	((w)[IEEE80211_AID(b) / 32] &= ~(1 << (IEEE80211_AID(b) % 32)))
80 #define	IEEE80211_AID_ISSET(b, w) \
81 	((w)[IEEE80211_AID(b) / 32] & (1 << (IEEE80211_AID(b) % 32)))
82 
83 static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
84 static void node_cleanup(struct ieee80211_node *);
85 static void node_free(struct ieee80211_node *);
86 static u_int8_t node_getrssi(const struct ieee80211_node *);
87 
88 static void ieee80211_setup_node(struct ieee80211_node_table *,
89 		struct ieee80211_node *, const u_int8_t *);
90 static void _ieee80211_free_node(struct ieee80211_node *);
91 static void ieee80211_free_allnodes(struct ieee80211_node_table *);
92 
93 static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
94 static void ieee80211_timeout_stations(struct ieee80211_node_table *);
95 
96 static void ieee80211_set_tim(struct ieee80211com *,
97 		struct ieee80211_node *, int set);
98 
99 static void ieee80211_node_table_init(struct ieee80211com *ic,
100 	struct ieee80211_node_table *nt, const char *name, int inact,
101 	void (*timeout)(struct ieee80211_node_table *));
102 static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
103 
104 MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
105 
106 void
107 ieee80211_node_attach(struct ieee80211com *ic)
108 {
109 	u_long sz;
110 
111 	ieee80211_node_table_init(ic, &ic->ic_sta, "station",
112 		IEEE80211_INACT_INIT, ieee80211_timeout_stations);
113 	ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
114 		IEEE80211_INACT_SCAN, ieee80211_timeout_scan_candidates);
115 
116 	ic->ic_node_alloc = node_alloc;
117 	ic->ic_node_free = node_free;
118 	ic->ic_node_cleanup = node_cleanup;
119 	ic->ic_node_getrssi = node_getrssi;
120 
121 	/* default station inactivity timer setings */
122 	ic->ic_inact_init = IEEE80211_INACT_INIT;
123 	ic->ic_inact_auth = IEEE80211_INACT_AUTH;
124 	ic->ic_inact_run = IEEE80211_INACT_RUN;
125 	ic->ic_inact_probe = IEEE80211_INACT_PROBE;
126 
127 	/* XXX defer */
128 	if (ic->ic_max_aid == 0)
129 		ic->ic_max_aid = IEEE80211_AID_DEF;
130 	else if (ic->ic_max_aid > IEEE80211_AID_MAX)
131 		ic->ic_max_aid = IEEE80211_AID_MAX;
132 	MALLOC(ic->ic_aid_bitmap, u_int32_t *,
133 		howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
134 		M_DEVBUF, M_NOWAIT | M_ZERO);
135 	if (ic->ic_aid_bitmap == NULL) {
136 		/* XXX no way to recover */
137 		printf("%s: no memory for AID bitmap!\n", __func__);
138 		ic->ic_max_aid = 0;
139 	}
140 
141 	/* XXX defer until using hostap/ibss mode */
142 	ic->ic_tim_len = sz = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
143 	MALLOC(ic->ic_tim_bitmap, u_int8_t *, sz, M_DEVBUF, M_NOWAIT | M_ZERO);
144 	if (ic->ic_tim_bitmap == NULL) {
145 		/* XXX no way to recover */
146 		printf("%s: no memory for TIM bitmap!\n", __func__);
147 	}
148 	ic->ic_set_tim = ieee80211_set_tim;	/* NB: driver should override */
149 }
150 
151 void
152 ieee80211_node_lateattach(struct ieee80211com *ic)
153 {
154 	struct ieee80211_node *ni;
155 	struct ieee80211_rsnparms *rsn;
156 
157 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
158 	IASSERT(ni != NULL, ("unable to setup inital BSS node"));
159 	/*
160 	 * Setup "global settings" in the bss node so that
161 	 * each new station automatically inherits them.
162 	 */
163 	rsn = &ni->ni_rsn;
164 	/* WEP, TKIP, and AES-CCM are always supported */
165 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
166 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
167 	rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
168 	if (ic->ic_caps & IEEE80211_C_AES)
169 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
170 	if (ic->ic_caps & IEEE80211_C_CKIP)
171 		rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
172 	/*
173 	 * Default unicast cipher to WEP for 802.1x use.  If
174 	 * WPA is enabled the management code will set these
175 	 * values to reflect.
176 	 */
177 	rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
178 	rsn->rsn_ucastkeylen = 104 / NBBY;
179 	/*
180 	 * WPA says the multicast cipher is the lowest unicast
181 	 * cipher supported.  But we skip WEP which would
182 	 * otherwise be used based on this criteria.
183 	 */
184 	rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
185 	rsn->rsn_mcastkeylen = 128 / NBBY;
186 
187 	/*
188 	 * We support both WPA-PSK and 802.1x; the one used
189 	 * is determined by the authentication mode and the
190 	 * setting of the PSK state.
191 	 */
192 	rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
193 	rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
194 
195 	ic->ic_bss = ieee80211_ref_node(ni);		/* hold reference */
196 	ic->ic_auth = ieee80211_authenticator_get(ni->ni_authmode);
197 }
198 
199 void
200 ieee80211_node_detach(struct ieee80211com *ic)
201 {
202 
203 	if (ic->ic_bss != NULL) {
204 		ieee80211_free_node(ic->ic_bss);
205 		ic->ic_bss = NULL;
206 	}
207 	ieee80211_node_table_cleanup(&ic->ic_scan);
208 	ieee80211_node_table_cleanup(&ic->ic_sta);
209 	if (ic->ic_aid_bitmap != NULL) {
210 		FREE(ic->ic_aid_bitmap, M_DEVBUF);
211 		ic->ic_aid_bitmap = NULL;
212 	}
213 	if (ic->ic_tim_bitmap != NULL) {
214 		FREE(ic->ic_tim_bitmap, M_DEVBUF);
215 		ic->ic_tim_bitmap = NULL;
216 	}
217 }
218 
219 /*
220  * Port authorize/unauthorize interfaces for use by an authenticator.
221  */
222 
223 void
224 ieee80211_node_authorize(struct ieee80211com *ic, struct ieee80211_node *ni)
225 {
226 	ni->ni_flags |= IEEE80211_NODE_AUTH;
227 	ni->ni_inact_reload = ic->ic_inact_run;
228 }
229 
230 void
231 ieee80211_node_unauthorize(struct ieee80211com *ic, struct ieee80211_node *ni)
232 {
233 	ni->ni_flags &= ~IEEE80211_NODE_AUTH;
234 }
235 
236 /*
237  * Set/change the channel.  The rate set is also updated as
238  * to insure a consistent view by drivers.
239  */
240 static __inline void
241 ieee80211_set_chan(struct ieee80211com *ic,
242 	struct ieee80211_node *ni, struct ieee80211_channel *chan)
243 {
244 	ni->ni_chan = chan;
245 	ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
246 }
247 
248 /*
249  * AP scanning support.
250  */
251 
252 #ifdef IEEE80211_DEBUG
253 static void
254 dump_chanlist(const u_char chans[])
255 {
256 	const char *sep;
257 	int i;
258 
259 	sep = " ";
260 	for (i = 0; i < IEEE80211_CHAN_MAX; i++)
261 		if (isset(chans, i)) {
262 			printf("%s%u", sep, i);
263 			sep = ", ";
264 		}
265 }
266 #endif /* IEEE80211_DEBUG */
267 
268 /*
269  * Initialize the channel set to scan based on the
270  * of available channels and the current PHY mode.
271  */
272 static void
273 ieee80211_reset_scan(struct ieee80211com *ic)
274 {
275 
276 	/* XXX ic_des_chan should be handled with ic_chan_active */
277 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
278 		memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
279 		setbit(ic->ic_chan_scan,
280 			ieee80211_chan2ieee(ic, ic->ic_des_chan));
281 	} else
282 		memcpy(ic->ic_chan_scan, ic->ic_chan_active,
283 			sizeof(ic->ic_chan_active));
284 	/* NB: hack, setup so next_scan starts with the first channel */
285 	if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC)
286 		ieee80211_set_chan(ic, ic->ic_bss,
287 			&ic->ic_channels[IEEE80211_CHAN_MAX]);
288 #ifdef IEEE80211_DEBUG
289 	if (ieee80211_msg_scan(ic)) {
290 		printf("%s: scan set:", __func__);
291 		dump_chanlist(ic->ic_chan_scan);
292 		printf(" start chan %u\n",
293 			ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan));
294 	}
295 #endif /* IEEE80211_DEBUG */
296 }
297 
298 /*
299  * Begin an active scan.
300  */
301 void
302 ieee80211_begin_scan(struct ieee80211com *ic, int reset)
303 {
304 
305 	ic->ic_scan.nt_scangen++;
306 	/*
307 	 * In all but hostap mode scanning starts off in
308 	 * an active mode before switching to passive.
309 	 */
310 	if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
311 		ic->ic_flags |= IEEE80211_F_ASCAN;
312 		ic->ic_stats.is_scan_active++;
313 	} else
314 		ic->ic_stats.is_scan_passive++;
315 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
316 		"begin %s scan in %s mode, scangen %u\n",
317 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
318 		ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
319 	/*
320 	 * Clear scan state and flush any previously seen AP's.
321 	 */
322 	ieee80211_reset_scan(ic);
323 	if (reset)
324 		ieee80211_free_allnodes(&ic->ic_scan);
325 
326 	ic->ic_flags |= IEEE80211_F_SCAN;
327 
328 	/* Scan the next channel. */
329 	ieee80211_next_scan(ic);
330 }
331 
332 /*
333  * Switch to the next channel marked for scanning.
334  */
335 int
336 ieee80211_next_scan(struct ieee80211com *ic)
337 {
338 	struct ieee80211_channel *chan;
339 
340 	/*
341 	 * Insure any previous mgt frame timeouts don't fire.
342 	 * This assumes the driver does the right thing in
343 	 * flushing anything queued in the driver and below.
344 	 */
345 	ic->ic_mgt_timer = 0;
346 
347 	chan = ic->ic_bss->ni_chan;
348 	do {
349 		if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
350 			chan = &ic->ic_channels[0];
351 		if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
352 			clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
353 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
354 			    "%s: chan %d->%d\n", __func__,
355 			    ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan),
356 			    ieee80211_chan2ieee(ic, chan));
357 			ieee80211_set_chan(ic, ic->ic_bss, chan);
358 #ifdef notyet
359 			/* XXX driver state change */
360 			/*
361 			 * Scan next channel. If doing an active scan
362 			 * and the channel is not marked passive-only
363 			 * then send a probe request.  Otherwise just
364 			 * listen for beacons on the channel.
365 			 */
366 			if ((ic->ic_flags & IEEE80211_F_ASCAN) &&
367 			    (ni->ni_chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) {
368 				IEEE80211_SEND_MGMT(ic, ni,
369 				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
370 			}
371 #else
372 			ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
373 #endif
374 			return 1;
375 		}
376 	} while (chan != ic->ic_bss->ni_chan);
377 	ieee80211_end_scan(ic);
378 	return 0;
379 }
380 
381 static __inline void
382 copy_bss(struct ieee80211_node *nbss, const struct ieee80211_node *obss)
383 {
384 	/* propagate useful state */
385 	nbss->ni_authmode = obss->ni_authmode;
386 	nbss->ni_txpower = obss->ni_txpower;
387 	nbss->ni_vlan = obss->ni_vlan;
388 	nbss->ni_rsn = obss->ni_rsn;
389 	/* XXX statistics? */
390 }
391 
392 void
393 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
394 {
395 	struct ieee80211_node_table *nt;
396 	struct ieee80211_node *ni;
397 
398 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
399 		"%s: creating ibss\n", __func__);
400 
401 	/*
402 	 * Create the station/neighbor table.  Note that for adhoc
403 	 * mode we make the initial inactivity timer longer since
404 	 * we create nodes only through discovery and they typically
405 	 * are long-lived associations.
406 	 */
407 	nt = &ic->ic_sta;
408 	IEEE80211_NODE_LOCK(nt);
409 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
410 		nt->nt_name = "station";
411 		nt->nt_inact_init = ic->ic_inact_init;
412 	} else {
413 		nt->nt_name = "neighbor";
414 		nt->nt_inact_init = ic->ic_inact_run;
415 	}
416 	IEEE80211_NODE_UNLOCK(nt);
417 
418 	ni = ieee80211_alloc_node(nt, ic->ic_myaddr);
419 	if (ni == NULL) {
420 		/* XXX recovery? */
421 		return;
422 	}
423 	if (ic->ic_opmode != IEEE80211_M_HOSTAP &&
424 	    (ic->ic_flags & IEEE80211_F_DESBSSID) != 0)
425 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
426 	else
427 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
428 	ni->ni_esslen = ic->ic_des_esslen;
429 	memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
430 	copy_bss(ni, ic->ic_bss);
431 	ni->ni_intval = ic->ic_lintval;
432 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
433 		ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
434 	if (ic->ic_phytype == IEEE80211_T_FH) {
435 		ni->ni_fhdwell = 200;	/* XXX */
436 		ni->ni_fhindex = 1;
437 	}
438 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
439 		ic->ic_flags |= IEEE80211_F_SIBSS;
440 		ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;	/* XXX */
441 		if (ic->ic_flags & IEEE80211_F_DESBSSID)
442 			IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
443 		else
444 		ni->ni_bssid[0] |= 0x02;	/* local bit for IBSS */
445 	}
446 	/*
447 	 * Fix the channel and related attributes.
448 	 */
449 	ieee80211_set_chan(ic, ni, chan);
450 	ic->ic_curmode = ieee80211_chan2mode(ic, chan);
451 	/*
452 	 * Do mode-specific rate setup.
453 	 */
454 	if (ic->ic_curmode == IEEE80211_MODE_11G) {
455 		/*
456 		 * Use a mixed 11b/11g rate set.
457 		 */
458 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
459 	} else if (ic->ic_curmode == IEEE80211_MODE_11B) {
460 		/*
461 		 * Force pure 11b rate set.
462 		 */
463 		ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
464 	}
465 
466 	(void) ieee80211_sta_join(ic, ieee80211_ref_node(ni));
467 }
468 
469 void
470 ieee80211_reset_bss(struct ieee80211com *ic)
471 {
472 	struct ieee80211_node *ni, *obss;
473 
474 	ieee80211_node_table_reset(&ic->ic_scan);
475 	ieee80211_node_table_reset(&ic->ic_sta);
476 
477 	ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
478 	IASSERT(ni != NULL, ("unable to setup inital BSS node"));
479 	obss = ic->ic_bss;
480 	ic->ic_bss = ieee80211_ref_node(ni);
481 	if (obss != NULL) {
482 		copy_bss(ni, obss);
483 		ni->ni_intval = ic->ic_lintval;
484 		ieee80211_free_node(obss);
485 	}
486 }
487 
488 static int
489 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
490 {
491         u_int8_t rate;
492         int fail;
493 
494 	fail = 0;
495 	if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
496 		fail |= 0x01;
497 	if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
498 	    ni->ni_chan != ic->ic_des_chan)
499 		fail |= 0x01;
500 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
501 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
502 			fail |= 0x02;
503 	} else {
504 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
505 			fail |= 0x02;
506 	}
507 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
508 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
509 			fail |= 0x04;
510 	} else {
511 		/* XXX does this mean privacy is supported or required? */
512 		if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
513 			fail |= 0x04;
514 	}
515 	rate = ieee80211_fix_rate(ic, ni,
516 			IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
517 	if (rate & IEEE80211_RATE_BASIC)
518 		fail |= 0x08;
519 	if (ic->ic_des_esslen != 0 &&
520 	    (ni->ni_esslen != ic->ic_des_esslen ||
521 	     memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
522 		fail |= 0x10;
523 	if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
524 	    !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
525 		fail |= 0x20;
526 #ifdef IEEE80211_DEBUG
527 	if (ieee80211_msg_scan(ic)) {
528 		printf(" %c %s", fail ? '-' : '+',
529 		    ether_sprintf(ni->ni_macaddr));
530 		printf(" %s%c", ether_sprintf(ni->ni_bssid),
531 		    fail & 0x20 ? '!' : ' ');
532 		printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
533 			fail & 0x01 ? '!' : ' ');
534 		printf(" %+4d", ni->ni_rssi);
535 		printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
536 		    fail & 0x08 ? '!' : ' ');
537 		printf(" %4s%c",
538 		    (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
539 		    (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
540 		    "????",
541 		    fail & 0x02 ? '!' : ' ');
542 		printf(" %3s%c ",
543 		    (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
544 		    "wep" : "no",
545 		    fail & 0x04 ? '!' : ' ');
546 		ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
547 		printf("%s\n", fail & 0x10 ? "!" : "");
548 	}
549 #endif
550 	return fail;
551 }
552 
553 static __inline u_int8_t
554 maxrate(const struct ieee80211_node *ni)
555 {
556 	const struct ieee80211_rateset *rs = &ni->ni_rates;
557 	/* NB: assumes rate set is sorted (happens on frame receive) */
558 	return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
559 }
560 
561 /*
562  * Compare the capabilities of two nodes and decide which is
563  * more desirable (return >0 if a is considered better).  Note
564  * that we assume compatibility/usability has already been checked
565  * so we don't need to (e.g. validate whether privacy is supported).
566  * Used to select the best scan candidate for association in a BSS.
567  */
568 static int
569 ieee80211_node_compare(struct ieee80211com *ic,
570 		       const struct ieee80211_node *a,
571 		       const struct ieee80211_node *b)
572 {
573 	u_int8_t maxa, maxb;
574 	u_int8_t rssia, rssib;
575 
576 	/* privacy support preferred */
577 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
578 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
579 		return 1;
580 	if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
581 	    (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
582 		return -1;
583 
584 	rssia = ic->ic_node_getrssi(a);
585 	rssib = ic->ic_node_getrssi(b);
586 	if (abs(rssib - rssia) < 5) {
587 		/* best/max rate preferred if signal level close enough XXX */
588 		maxa = maxrate(a);
589 		maxb = maxrate(b);
590 		if (maxa != maxb)
591 			return maxa - maxb;
592 		/* XXX use freq for channel preference */
593 		/* for now just prefer 5Ghz band to all other bands */
594 		if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
595 		   !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
596 			return 1;
597 		if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
598 		     IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
599 			return -1;
600 	}
601 	/* all things being equal, use signal level */
602 	return rssia - rssib;
603 }
604 
605 /*
606  * Mark an ongoing scan stopped.
607  */
608 void
609 ieee80211_cancel_scan(struct ieee80211com *ic)
610 {
611 
612 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
613 		__func__,
614 		(ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
615 
616 	ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
617 }
618 
619 /*
620  * Complete a scan of potential channels.
621  */
622 void
623 ieee80211_end_scan(struct ieee80211com *ic)
624 {
625 	struct ieee80211_node_table *nt = &ic->ic_scan;
626 	struct ieee80211_node *ni, *selbs;
627 
628 	ieee80211_cancel_scan(ic);
629 	ieee80211_notify_scan_done(ic);
630 
631 #ifndef IEEE80211_NO_HOSTAP
632 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
633 		u_int8_t maxrssi[IEEE80211_CHAN_MAX];	/* XXX off stack? */
634 		int i, bestchan;
635 		u_int8_t rssi;
636 
637 		/*
638 		 * The passive scan to look for existing AP's completed,
639 		 * select a channel to camp on.  Identify the channels
640 		 * that already have one or more AP's and try to locate
641 		 * an unoccupied one.  If that fails, pick a channel that
642 		 * looks to be quietest.
643 		 */
644 		memset(maxrssi, 0, sizeof(maxrssi));
645 		IEEE80211_NODE_LOCK(nt);
646 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
647 			rssi = ic->ic_node_getrssi(ni);
648 			i = ieee80211_chan2ieee(ic, ni->ni_chan);
649 			if (rssi > maxrssi[i])
650 				maxrssi[i] = rssi;
651 		}
652 		IEEE80211_NODE_UNLOCK(nt);
653 		/* XXX select channel more intelligently */
654 		bestchan = -1;
655 		for (i = 0; i < IEEE80211_CHAN_MAX; i++)
656 			if (isset(ic->ic_chan_active, i)) {
657 				/*
658 				 * If the channel is unoccupied the max rssi
659 				 * should be zero; just take it.  Otherwise
660 				 * track the channel with the lowest rssi and
661 				 * use that when all channels appear occupied.
662 				 */
663 				if (maxrssi[i] == 0) {
664 					bestchan = i;
665 					break;
666 				}
667 				if (bestchan == -1 ||
668 				    maxrssi[i] < maxrssi[bestchan])
669 					bestchan = i;
670 			}
671 		if (bestchan != -1) {
672 			ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
673 			return;
674 		}
675 		/* no suitable channel, should not happen */
676 	}
677 #endif /* !IEEE80211_NO_HOSTAP */
678 
679 	/*
680 	 * When manually sequencing the state machine; scan just once
681 	 * regardless of whether we have a candidate or not.  The
682 	 * controlling application is expected to setup state and
683 	 * initiate an association.
684 	 */
685 	if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
686 		return;
687 	/*
688 	 * Automatic sequencing; look for a candidate and
689 	 * if found join the network.
690 	 */
691 	/* NB: unlocked read should be ok */
692 	if (TAILQ_FIRST(&nt->nt_node) == NULL) {
693 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
694 			"%s: no scan candidate\n", __func__);
695   notfound:
696 		if (ic->ic_opmode == IEEE80211_M_IBSS &&
697 		    (ic->ic_flags & IEEE80211_F_IBSSON) &&
698 		    ic->ic_des_esslen != 0) {
699 			ieee80211_create_ibss(ic, ic->ic_ibss_chan);
700 			return;
701 		}
702 		/*
703 		 * Reset the list of channels to scan and start again.
704 		 */
705 		ieee80211_reset_scan(ic);
706 		ic->ic_flags |= IEEE80211_F_SCAN;
707 		ieee80211_next_scan(ic);
708 		return;
709 	}
710 	selbs = NULL;
711 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
712 	    "macaddr          bssid         chan  rssi rate flag  wep  essid");
713 	IEEE80211_NODE_LOCK(nt);
714 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
715 		if (ni->ni_fails) {
716 			/*
717 			 * The configuration of the access points may change
718 			 * during my scan.  So delete the entry for the AP
719 			 * and retry to associate if there is another beacon.
720 			 */
721 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
722 				"%s: skip scan candidate %s, fails %u\n",
723 				__func__, ether_sprintf(ni->ni_macaddr),
724 				ni->ni_fails);
725 			ni->ni_fails++;
726 #if 0
727 			if (ni->ni_fails++ > 2)
728 				ieee80211_free_node(ni);
729 #endif
730 			continue;
731 		}
732 		if (ieee80211_match_bss(ic, ni) == 0) {
733 			if (selbs == NULL)
734 				selbs = ni;
735 			else if (ieee80211_node_compare(ic, ni, selbs) > 0)
736 				selbs = ni;
737 		}
738 	}
739 	if (selbs != NULL)		/* NB: grab ref while dropping lock */
740 		(void) ieee80211_ref_node(selbs);
741 	IEEE80211_NODE_UNLOCK(nt);
742 	if (selbs == NULL)
743 		goto notfound;
744 	if (!ieee80211_sta_join(ic, selbs)) {
745 		ieee80211_free_node(selbs);
746 		goto notfound;
747 	}
748 }
749 
750 /*
751  * Handle 802.11 ad hoc network merge.  The
752  * convention, set by the Wireless Ethernet Compatibility Alliance
753  * (WECA), is that an 802.11 station will change its BSSID to match
754  * the "oldest" 802.11 ad hoc network, on the same channel, that
755  * has the station's desired SSID.  The "oldest" 802.11 network
756  * sends beacons with the greatest TSF timestamp.
757  *
758  * The caller is assumed to validate TSF's before attempting a merge.
759  *
760  * Return !0 if the BSSID changed, 0 otherwise.
761  */
762 int
763 ieee80211_ibss_merge(struct ieee80211com *ic, struct ieee80211_node *ni)
764 {
765 
766 	if (ni == ic->ic_bss ||
767 	    IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
768 		/* unchanged, nothing to do */
769 		return 0;
770 	}
771 	if (ieee80211_match_bss(ic, ni) != 0) {	/* capabilities mismatch */
772 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
773 		    "%s: merge failed, capabilities mismatch\n", __func__);
774 		ic->ic_stats.is_ibss_capmismatch++;
775 		return 0;
776 	}
777 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
778 		"%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
779 		ether_sprintf(ni->ni_bssid),
780 		ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
781 		ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
782 		ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
783 	);
784 	return ieee80211_sta_join(ic, ieee80211_ref_node(ni));
785 }
786 
787 /*
788  * Join the specified IBSS/BSS network.  The node is assumed to
789  * be passed in with a held reference.
790  */
791 int
792 ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
793 {
794 	struct ieee80211_node *obss;
795 
796 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
797 		struct ieee80211_node_table *nt;
798 		/*
799 		 * Delete unusable rates; we've already checked
800 		 * that the negotiated rate set is acceptable.
801 		 */
802 		ieee80211_fix_rate(ic, selbs, IEEE80211_F_DODEL);
803 		/*
804 		 * Fillin the neighbor table; it will already
805 		 * exist if we are simply switching mastership.
806 		 * XXX ic_sta always setup so this is unnecessary?
807 		 */
808 		nt = &ic->ic_sta;
809 		IEEE80211_NODE_LOCK(nt);
810 		nt->nt_name = "neighbor";
811 		nt->nt_inact_init = ic->ic_inact_run;
812 		IEEE80211_NODE_UNLOCK(nt);
813 	}
814 
815 	/*
816 	 * Committed to selbs, setup state.
817 	 */
818 	obss = ic->ic_bss;
819 	ic->ic_bss = selbs;		/* NB: caller assumed to bump refcnt */
820 	if (obss != NULL)
821 		ieee80211_free_node(obss);
822 	/*
823 	 * Set the erp state (mostly the slot time) to deal with
824 	 * the auto-select case; this should be redundant if the
825 	 * mode is locked.
826 	 */
827 	ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
828 	ieee80211_reset_erp(ic);
829 	ieee80211_wme_initparams(ic);
830 
831 	if (ic->ic_opmode == IEEE80211_M_STA)
832 		ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
833 	else
834 		ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
835 	return 1;
836 }
837 
838 /*
839  * Leave the specified IBSS/BSS network.  The node is assumed to
840  * be passed in with a held reference.
841  */
842 void
843 ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
844 {
845 	ic->ic_node_cleanup(ni);
846 	ieee80211_notify_node_leave(ic, ni);
847 }
848 
849 int
850 ieee80211_get_rate(struct ieee80211com *ic)
851 {
852 	u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE];
853 	int rate;
854 
855 	rates = &ic->ic_bss->ni_rates.rs_rates;
856 
857 	if (ic->ic_fixed_rate != -1)
858 		rate = (*rates)[ic->ic_fixed_rate];
859 	else if (ic->ic_state == IEEE80211_S_RUN)
860 		rate = (*rates)[ic->ic_bss->ni_txrate];
861 	else
862 		rate = 0;
863 
864 	return rate & IEEE80211_RATE_VAL;
865 }
866 
867 static struct ieee80211_node *
868 node_alloc(struct ieee80211_node_table *nt)
869 {
870 	struct ieee80211_node *ni;
871 
872 	MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
873 		M_80211_NODE, M_NOWAIT | M_ZERO);
874 	return ni;
875 }
876 
877 /*
878  * Reclaim any resources in a node and reset any critical
879  * state.  Typically nodes are free'd immediately after,
880  * but in some cases the storage may be reused so we need
881  * to insure consistent state (should probably fix that).
882  */
883 static void
884 node_cleanup(struct ieee80211_node *ni)
885 {
886 #define	N(a)	(sizeof(a)/sizeof(a[0]))
887 	struct ieee80211com *ic = ni->ni_ic;
888 	int i, qlen;
889 
890 	/* NB: preserve ni_table */
891 	if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
892 		ic->ic_ps_sta--;
893 		ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
894 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
895 		    "[%s] power save mode off, %u sta's in ps mode\n",
896 		    ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
897 	}
898 	/*
899 	 * Clear AREF flag that marks the authorization refcnt bump
900 	 * has happened.  This is probably not needed as the node
901 	 * should always be removed from the table so not found but
902 	 * do it just in case.
903 	 */
904 	ni->ni_flags &= ~IEEE80211_NODE_AREF;
905 
906 	/*
907 	 * Drain power save queue and, if needed, clear TIM.
908 	 */
909 	IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
910 	if (qlen != 0 && ic->ic_set_tim != NULL)
911 		ic->ic_set_tim(ic, ni, 0);
912 
913 	ni->ni_associd = 0;
914 	if (ni->ni_challenge != NULL) {
915 		FREE(ni->ni_challenge, M_DEVBUF);
916 		ni->ni_challenge = NULL;
917 	}
918 	/*
919 	 * Preserve SSID, WPA, and WME ie's so the bss node is
920 	 * reusable during a re-auth/re-assoc state transition.
921 	 * If we remove these data they will not be recreated
922 	 * because they come from a probe-response or beacon frame
923 	 * which cannot be expected prior to the association-response.
924 	 * This should not be an issue when operating in other modes
925 	 * as stations leaving always go through a full state transition
926 	 * which will rebuild this state.
927 	 *
928 	 * XXX does this leave us open to inheriting old state?
929 	 */
930 	for (i = 0; i < N(ni->ni_rxfrag); i++)
931 		if (ni->ni_rxfrag[i] != NULL) {
932 			m_freem(ni->ni_rxfrag[i]);
933 			ni->ni_rxfrag[i] = NULL;
934 		}
935 	ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
936 #undef N
937 }
938 
939 static void
940 node_free(struct ieee80211_node *ni)
941 {
942 	struct ieee80211com *ic = ni->ni_ic;
943 
944 	ic->ic_node_cleanup(ni);
945 	if (ni->ni_wpa_ie != NULL)
946 		FREE(ni->ni_wpa_ie, M_DEVBUF);
947 	if (ni->ni_wme_ie != NULL)
948 		FREE(ni->ni_wme_ie, M_DEVBUF);
949 	IEEE80211_NODE_SAVEQ_DESTROY(ni);
950 	FREE(ni, M_80211_NODE);
951 }
952 
953 static u_int8_t
954 node_getrssi(const struct ieee80211_node *ni)
955 {
956 	return ni->ni_rssi;
957 }
958 
959 static void
960 ieee80211_setup_node(struct ieee80211_node_table *nt,
961 	struct ieee80211_node *ni, const u_int8_t *macaddr)
962 {
963 	struct ieee80211com *ic = nt->nt_ic;
964 	int hash;
965 
966 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
967 		"%s %p<%s> in %s table\n", __func__, ni,
968 		ether_sprintf(macaddr), nt->nt_name);
969 
970 	IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
971 	hash = IEEE80211_NODE_HASH(macaddr);
972 	ieee80211_node_initref(ni);		/* mark referenced */
973 	ni->ni_chan = IEEE80211_CHAN_ANYC;
974 	ni->ni_authmode = IEEE80211_AUTH_OPEN;
975 	ni->ni_txpower = ic->ic_txpowlimit;	/* max power */
976 	ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
977 	ni->ni_inact_reload = nt->nt_inact_init;
978 	ni->ni_inact = ni->ni_inact_reload;
979 	IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
980 
981 	IEEE80211_NODE_LOCK(nt);
982 	TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
983 	LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
984 	ni->ni_table = nt;
985 	ni->ni_ic = ic;
986 	IEEE80211_NODE_UNLOCK(nt);
987 }
988 
989 struct ieee80211_node *
990 ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
991 {
992 	struct ieee80211com *ic = nt->nt_ic;
993 	struct ieee80211_node *ni;
994 
995 	ni = ic->ic_node_alloc(nt);
996 	if (ni != NULL)
997 		ieee80211_setup_node(nt, ni, macaddr);
998 	else
999 		ic->ic_stats.is_rx_nodealloc++;
1000 	return ni;
1001 }
1002 
1003 struct ieee80211_node *
1004 ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1005 {
1006 	struct ieee80211com *ic = nt->nt_ic;
1007 	struct ieee80211_node *ni;
1008 
1009 	ni = ic->ic_node_alloc(nt);
1010 	if (ni != NULL) {
1011 		ieee80211_setup_node(nt, ni, macaddr);
1012 		/*
1013 		 * Inherit from ic_bss.
1014 		 */
1015 		ni->ni_authmode = ic->ic_bss->ni_authmode;
1016 		ni->ni_txpower = ic->ic_bss->ni_txpower;
1017 		ni->ni_vlan = ic->ic_bss->ni_vlan;	/* XXX?? */
1018 		IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
1019 		ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
1020 		ni->ni_rsn = ic->ic_bss->ni_rsn;
1021 	} else
1022 		ic->ic_stats.is_rx_nodealloc++;
1023 	return ni;
1024 }
1025 
1026 static struct ieee80211_node *
1027 #ifdef IEEE80211_DEBUG_REFCNT
1028 _ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1029 	const u_int8_t *macaddr, const char *func, int line)
1030 #else
1031 _ieee80211_find_node(struct ieee80211_node_table *nt,
1032 	const u_int8_t *macaddr)
1033 #endif
1034 {
1035 	struct ieee80211_node *ni;
1036 	int hash;
1037 
1038 	IEEE80211_NODE_LOCK_ASSERT(nt);
1039 
1040 	hash = IEEE80211_NODE_HASH(macaddr);
1041 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1042 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
1043 			ieee80211_ref_node(ni);	/* mark referenced */
1044 #ifdef IEEE80211_DEBUG_REFCNT
1045 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1046 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1047 			    func, line,
1048 			    ni, ether_sprintf(ni->ni_macaddr),
1049 			    ieee80211_node_refcnt(ni));
1050 #endif
1051 			return ni;
1052 		}
1053 	}
1054 	return NULL;
1055 }
1056 #ifdef IEEE80211_DEBUG_REFCNT
1057 #define	_ieee80211_find_node(nt, mac) \
1058 	_ieee80211_find_node_debug(nt, mac, func, line)
1059 #endif
1060 
1061 struct ieee80211_node *
1062 #ifdef IEEE80211_DEBUG_REFCNT
1063 ieee80211_find_node_debug(struct ieee80211_node_table *nt,
1064 	const u_int8_t *macaddr, const char *func, int line)
1065 #else
1066 ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
1067 #endif
1068 {
1069 	struct ieee80211_node *ni;
1070 
1071 	IEEE80211_NODE_LOCK(nt);
1072 	ni = _ieee80211_find_node(nt, macaddr);
1073 	IEEE80211_NODE_UNLOCK(nt);
1074 	return ni;
1075 }
1076 
1077 /*
1078  * Fake up a node; this handles node discovery in adhoc mode.
1079  * Note that for the driver's benefit we we treat this like
1080  * an association so the driver has an opportunity to setup
1081  * it's private state.
1082  */
1083 struct ieee80211_node *
1084 ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
1085 	const u_int8_t macaddr[IEEE80211_ADDR_LEN])
1086 {
1087 	struct ieee80211com *ic = nt->nt_ic;
1088 	struct ieee80211_node *ni;
1089 
1090 	ni = ieee80211_dup_bss(nt, macaddr);
1091 	if (ni != NULL) {
1092 		/* XXX no rate negotiation; just dup */
1093 		ni->ni_rates = ic->ic_bss->ni_rates;
1094 		if (ic->ic_newassoc != NULL)
1095 			ic->ic_newassoc(ic, ni, 1);
1096 		/* XXX not right for 802.1x/WPA */
1097 		ieee80211_node_authorize(ic, ni);
1098 	}
1099 	return ni;
1100 }
1101 
1102 /*
1103  * Locate the node for sender, track state, and then pass the
1104  * (referenced) node up to the 802.11 layer for its use.  We
1105  * are required to pass some node so we fall back to ic_bss
1106  * when this frame is from an unknown sender.  The 802.11 layer
1107  * knows this means the sender wasn't in the node table and
1108  * acts accordingly.
1109  */
1110 struct ieee80211_node *
1111 #ifdef IEEE80211_DEBUG_REFCNT
1112 ieee80211_find_rxnode_debug(struct ieee80211com *ic,
1113 	const struct ieee80211_frame_min *wh, const char *func, int line)
1114 #else
1115 ieee80211_find_rxnode(struct ieee80211com *ic,
1116 	const struct ieee80211_frame_min *wh)
1117 #endif
1118 {
1119 #define	IS_CTL(wh) \
1120 	((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
1121 #define	IS_PSPOLL(wh) \
1122 	((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
1123 	struct ieee80211_node_table *nt;
1124 	struct ieee80211_node *ni;
1125 
1126 	/* XXX may want scanned nodes in the neighbor table for adhoc */
1127 	if (ic->ic_opmode == IEEE80211_M_STA ||
1128 	    ic->ic_opmode == IEEE80211_M_MONITOR ||
1129 	    (ic->ic_flags & IEEE80211_F_SCAN))
1130 		nt = &ic->ic_scan;
1131 	else
1132 		nt = &ic->ic_sta;
1133 	/* XXX check ic_bss first in station mode */
1134 	/* XXX 4-address frames? */
1135 	IEEE80211_NODE_LOCK(nt);
1136 	if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
1137 		ni = _ieee80211_find_node(nt, wh->i_addr1);
1138 	else
1139 		ni = _ieee80211_find_node(nt, wh->i_addr2);
1140 	IEEE80211_NODE_UNLOCK(nt);
1141 
1142 	return (ni != NULL ? ni : ieee80211_ref_node(ic->ic_bss));
1143 #undef IS_PSPOLL
1144 #undef IS_CTL
1145 }
1146 
1147 /*
1148  * Return a reference to the appropriate node for sending
1149  * a data frame.  This handles node discovery in adhoc networks.
1150  */
1151 struct ieee80211_node *
1152 #ifdef IEEE80211_DEBUG_REFCNT
1153 ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
1154 	const char *func, int line)
1155 #else
1156 ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
1157 #endif
1158 {
1159 	struct ieee80211_node_table *nt = &ic->ic_sta;
1160 	struct ieee80211_node *ni;
1161 
1162 	/*
1163 	 * The destination address should be in the node table
1164 	 * unless we are operating in station mode or this is a
1165 	 * multicast/broadcast frame.
1166 	 */
1167 	if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
1168 		return ieee80211_ref_node(ic->ic_bss);
1169 
1170 	/* XXX can't hold lock across dup_bss 'cuz of recursive locking */
1171 	IEEE80211_NODE_LOCK(nt);
1172 	ni = _ieee80211_find_node(nt, macaddr);
1173 	IEEE80211_NODE_UNLOCK(nt);
1174 
1175 	if (ni == NULL) {
1176 		if (ic->ic_opmode == IEEE80211_M_IBSS ||
1177 		    ic->ic_opmode == IEEE80211_M_AHDEMO) {
1178 			/*
1179 			 * In adhoc mode cons up a node for the destination.
1180 			 * Note that we need an additional reference for the
1181 			 * caller to be consistent with _ieee80211_find_node.
1182 			 */
1183 			ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
1184 			if (ni != NULL)
1185 				(void) ieee80211_ref_node(ni);
1186 		} else {
1187 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
1188 				"[%s] no node, discard frame (%s)\n",
1189 				ether_sprintf(macaddr), __func__);
1190 			ic->ic_stats.is_tx_nonode++;
1191 		}
1192 	}
1193 	return ni;
1194 }
1195 
1196 /*
1197  * Like find but search based on the channel too.
1198  */
1199 struct ieee80211_node *
1200 #ifdef IEEE80211_DEBUG_REFCNT
1201 ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
1202 	const u_int8_t *macaddr, struct ieee80211_channel *chan,
1203 	const char *func, int line)
1204 #else
1205 ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
1206 	const u_int8_t *macaddr, struct ieee80211_channel *chan)
1207 #endif
1208 {
1209 	struct ieee80211_node *ni;
1210 	int hash;
1211 
1212 	hash = IEEE80211_NODE_HASH(macaddr);
1213 	IEEE80211_NODE_LOCK(nt);
1214 	LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1215 		if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1216 		    ni->ni_chan == chan) {
1217 			ieee80211_ref_node(ni);		/* mark referenced */
1218 			IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
1219 #ifdef IEEE80211_DEBUG_REFCNT
1220 			    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1221 			    func, line,
1222 #else
1223 			    "%s %p<%s> refcnt %d\n", __func__,
1224 #endif
1225 			    ni, ether_sprintf(ni->ni_macaddr),
1226 			    ieee80211_node_refcnt(ni));
1227 			break;
1228 		}
1229 	}
1230 	IEEE80211_NODE_UNLOCK(nt);
1231 	return ni;
1232 }
1233 
1234 struct ieee80211_node *
1235 ieee80211_refine_node_for_beacon(struct ieee80211com *ic,
1236 	struct ieee80211_node *ni0, struct ieee80211_channel *chan,
1237 	const u_int8_t *ssid)
1238 {
1239 	struct ieee80211_node_table *nt = ni0->ni_table;
1240 	struct ieee80211_node *best, *ni;
1241 	int best_score = 0, score;
1242 
1243 	if (nt == NULL)
1244 		return ni0;
1245 
1246 	best = ni0;
1247 	if (ssid[1] == 0 || best->ni_esslen == 0)
1248 		best_score = 1;
1249 	else if (ssid[1] == best->ni_esslen &&
1250 		 memcmp(ssid + 2, best->ni_essid, ssid[1]) == 0)
1251 		best_score = 2;
1252 	else
1253 		best_score = 0;
1254 
1255 	IEEE80211_NODE_LOCK(nt);
1256 	for (ni = LIST_NEXT(ni0, ni_hash); ni != NULL;
1257 	     ni = LIST_NEXT(ni, ni_hash)) {
1258 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, best->ni_macaddr) ||
1259 		    ni->ni_ic != best->ni_ic || ni->ni_chan != chan)
1260 			continue;
1261 
1262 		if (ssid[1] == 0 || ni->ni_esslen == 0)
1263 			score = 1;
1264 		else if (ssid[1] == ni->ni_esslen &&
1265 			 memcmp(ssid + 2, ni->ni_essid, ssid[1]) == 0)
1266 			score = 2;
1267 		else
1268 			continue;
1269 
1270 		if (score > best_score) {
1271 			best = ni;
1272 			best_score = score;
1273 		}
1274 	}
1275 	IEEE80211_NODE_UNLOCK(nt);
1276 	return best;
1277 }
1278 
1279 /*
1280  * Like find but search based on the ssid too.
1281  */
1282 struct ieee80211_node *
1283 #ifdef IEEE80211_DEBUG_REFCNT
1284 ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
1285 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
1286 	const char *func, int line)
1287 #else
1288 ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
1289 	const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
1290 #endif
1291 {
1292 #define	MATCH_SSID(ni, ssid, ssidlen) \
1293 	(ni->ni_esslen == ssidlen && memcmp(ni->ni_essid, ssid, ssidlen) == 0)
1294 	static const u_int8_t zeromac[IEEE80211_ADDR_LEN];
1295 	struct ieee80211com *ic = nt->nt_ic;
1296 	struct ieee80211_node *ni;
1297 	int hash;
1298 
1299 	IEEE80211_NODE_LOCK(nt);
1300 	/*
1301 	 * A mac address that is all zero means match only the ssid;
1302 	 * otherwise we must match both.
1303 	 */
1304 	if (IEEE80211_ADDR_EQ(macaddr, zeromac)) {
1305 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1306 			if (MATCH_SSID(ni, ssid, ssidlen))
1307 				break;
1308 		}
1309 	} else {
1310 		hash = IEEE80211_NODE_HASH(macaddr);
1311 		LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
1312 			if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
1313 			    MATCH_SSID(ni, ssid, ssidlen))
1314 				break;
1315 		}
1316 	}
1317 	if (ni != NULL) {
1318 		ieee80211_ref_node(ni);	/* mark referenced */
1319 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1320 #ifdef IEEE80211_DEBUG_REFCNT
1321 		    "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
1322 		    func, line,
1323 #else
1324 		    "%s %p<%s> refcnt %d\n", __func__,
1325 #endif
1326 		     ni, ether_sprintf(ni->ni_macaddr),
1327 		     ieee80211_node_refcnt(ni));
1328 	}
1329 	IEEE80211_NODE_UNLOCK(nt);
1330 	return ni;
1331 #undef MATCH_SSID
1332 }
1333 
1334 static void
1335 _ieee80211_free_node(struct ieee80211_node *ni)
1336 {
1337 	struct ieee80211com *ic = ni->ni_ic;
1338 	struct ieee80211_node_table *nt = ni->ni_table;
1339 
1340 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1341 		"%s %p<%s> in %s table\n", __func__, ni,
1342 		ether_sprintf(ni->ni_macaddr),
1343 		nt != NULL ? nt->nt_name : "<gone>");
1344 
1345 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1346 	if (nt != NULL) {
1347 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1348 		LIST_REMOVE(ni, ni_hash);
1349 	}
1350 	ic->ic_node_free(ni);
1351 }
1352 
1353 void
1354 #ifdef IEEE80211_DEBUG_REFCNT
1355 ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
1356 #else
1357 ieee80211_free_node(struct ieee80211_node *ni)
1358 #endif
1359 {
1360 	struct ieee80211_node_table *nt = ni->ni_table;
1361 
1362 #ifdef IEEE80211_DEBUG_REFCNT
1363 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1364 		"%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line, ni,
1365 		 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
1366 #endif
1367 	if (ieee80211_node_dectestref(ni)) {
1368 		/*
1369 		 * Beware; if the node is marked gone then it's already
1370 		 * been removed from the table and we cannot assume the
1371 		 * table still exists.  Regardless, there's no need to lock
1372 		 * the table.
1373 		 */
1374 		if (ni->ni_table != NULL) {
1375 			IEEE80211_NODE_LOCK(nt);
1376 			_ieee80211_free_node(ni);
1377 			IEEE80211_NODE_UNLOCK(nt);
1378 		} else
1379 			_ieee80211_free_node(ni);
1380 	}
1381 }
1382 
1383 /*
1384  * Reclaim a node.  If this is the last reference count then
1385  * do the normal free work.  Otherwise remove it from the node
1386  * table and mark it gone by clearing the back-reference.
1387  */
1388 static void
1389 node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1390 {
1391 
1392 	IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
1393 		"%s: remove %p<%s> from %s table, refcnt %d\n",
1394 		__func__, ni, ether_sprintf(ni->ni_macaddr),
1395 		nt->nt_name, ieee80211_node_refcnt(ni)-1);
1396 	if (!ieee80211_node_dectestref(ni)) {
1397 		/*
1398 		 * Other references are present, just remove the
1399 		 * node from the table so it cannot be found.  When
1400 		 * the references are dropped storage will be
1401 		 * reclaimed.
1402 		 */
1403 		TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
1404 		LIST_REMOVE(ni, ni_hash);
1405 		ni->ni_table = NULL;		/* clear reference */
1406 	} else
1407 		_ieee80211_free_node(ni);
1408 }
1409 
1410 static void
1411 ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
1412 {
1413 	struct ieee80211com *ic = nt->nt_ic;
1414 	struct ieee80211_node *ni;
1415 
1416 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1417 		"%s: free all nodes in %s table\n", __func__, nt->nt_name);
1418 
1419 	while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
1420 		if (ni->ni_associd != 0) {
1421 			if (ic->ic_auth->ia_node_leave != NULL)
1422 				ic->ic_auth->ia_node_leave(ic, ni);
1423 			IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1424 		}
1425 		node_reclaim(nt, ni);
1426 	}
1427 	ieee80211_reset_erp(ic);
1428 }
1429 
1430 static void
1431 ieee80211_free_allnodes(struct ieee80211_node_table *nt)
1432 {
1433 
1434 	IEEE80211_NODE_LOCK(nt);
1435 	ieee80211_free_allnodes_locked(nt);
1436 	IEEE80211_NODE_UNLOCK(nt);
1437 }
1438 
1439 /*
1440  * Timeout entries in the scan cache.
1441  */
1442 static void
1443 ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
1444 {
1445 	struct ieee80211com *ic = nt->nt_ic;
1446 	struct ieee80211_node *ni, *tni;
1447 
1448 	IEEE80211_NODE_LOCK(nt);
1449 	ni = ic->ic_bss;
1450 	/* XXX belongs elsewhere */
1451 	if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
1452 		m_freem(ni->ni_rxfrag[0]);
1453 		ni->ni_rxfrag[0] = NULL;
1454 	}
1455 	TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
1456 		if (ni->ni_inact && --ni->ni_inact == 0) {
1457 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1458 			    "[%s] scan candidate purged from cache "
1459 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1460 			    ieee80211_node_refcnt(ni));
1461 			node_reclaim(nt, ni);
1462 		}
1463 	}
1464 	IEEE80211_NODE_UNLOCK(nt);
1465 
1466 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1467 }
1468 
1469 /*
1470  * Timeout inactive stations and do related housekeeping.
1471  * Note that we cannot hold the node lock while sending a
1472  * frame as this would lead to a LOR.  Instead we use a
1473  * generation number to mark nodes that we've scanned and
1474  * drop the lock and restart a scan if we have to time out
1475  * a node.  Since we are single-threaded by virtue of
1476  * controlling the inactivity timer we can be sure this will
1477  * process each node only once.
1478  */
1479 static void
1480 ieee80211_timeout_stations(struct ieee80211_node_table *nt)
1481 {
1482 	struct ieee80211com *ic = nt->nt_ic;
1483 	struct ieee80211_node *ni;
1484 	u_int gen;
1485 
1486 	IEEE80211_SCAN_LOCK(nt);
1487 	gen = nt->nt_scangen++;
1488 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1489 		"%s: %s scangen %u\n", __func__, nt->nt_name, gen);
1490 restart:
1491 	IEEE80211_NODE_LOCK(nt);
1492 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1493 		if (ni->ni_scangen == gen)	/* previously handled */
1494 			continue;
1495 		ni->ni_scangen = gen;
1496 		/*
1497 		 * Ignore entries for which have yet to receive an
1498 		 * authentication frame.  These are transient and
1499 		 * will be reclaimed when the last reference to them
1500 		 * goes away (when frame xmits complete).
1501 		 */
1502 		if ((ni->ni_flags & IEEE80211_NODE_AREF) == 0)
1503 			continue;
1504 		/*
1505 		 * Free fragment if not needed anymore
1506 		 * (last fragment older than 1s).
1507 		 * XXX doesn't belong here
1508 		 */
1509 		if (ni->ni_rxfrag[0] != NULL &&
1510 		    ticks > ni->ni_rxfragstamp + hz) {
1511 			m_freem(ni->ni_rxfrag[0]);
1512 			ni->ni_rxfrag[0] = NULL;
1513 		}
1514 		/*
1515 		 * Special case ourself; we may be idle for extended periods
1516 		 * of time and regardless reclaiming our state is wrong.
1517 		 */
1518 		if (ni == ic->ic_bss)
1519 			continue;
1520 		ni->ni_inact--;
1521 		if (ni->ni_associd != 0) {
1522 			/*
1523 			 * Age frames on the power save queue. The
1524 			 * aging interval is 4 times the listen
1525 			 * interval specified by the station.  This
1526 			 * number is factored into the age calculations
1527 			 * when the frame is placed on the queue.  We
1528 			 * store ages as time differences we can check
1529 			 * and/or adjust only the head of the list.
1530 			 */
1531 			if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
1532 				struct mbuf *m;
1533 				int discard = 0;
1534 
1535 				IEEE80211_NODE_SAVEQ_LOCK(ni);
1536 				while (IF_POLL(&ni->ni_savedq, m) != NULL &&
1537 				     M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
1538 IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
1539 					_IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
1540 					m_freem(m);
1541 					discard++;
1542 				}
1543 				if (m != NULL)
1544 					M_AGE_SUB(m, IEEE80211_INACT_WAIT);
1545 				IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1546 
1547 				if (discard != 0) {
1548 					IEEE80211_DPRINTF(ic,
1549 					    IEEE80211_MSG_POWER,
1550 					    "[%s] discard %u frames for age\n",
1551 					    ether_sprintf(ni->ni_macaddr),
1552 					    discard);
1553 					IEEE80211_NODE_STAT_ADD(ni,
1554 						ps_discard, discard);
1555 					if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
1556 						ic->ic_set_tim(ic, ni, 0);
1557 				}
1558 			}
1559 			/*
1560 			 * Probe the station before time it out.  We
1561 			 * send a null data frame which may not be
1562 			 * universally supported by drivers (need it
1563 			 * for ps-poll support so it should be...).
1564 			 */
1565 			if (0 < ni->ni_inact &&
1566 			    ni->ni_inact <= ic->ic_inact_probe) {
1567 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1568 				    "[%s] probe station due to inactivity\n",
1569 				    ether_sprintf(ni->ni_macaddr));
1570 				IEEE80211_NODE_UNLOCK(nt);
1571 				ieee80211_send_nulldata(ic, ni);
1572 				/* XXX stat? */
1573 				goto restart;
1574 			}
1575 		}
1576 		if (ni->ni_inact <= 0) {
1577 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1578 			    "[%s] station timed out due to inactivity "
1579 			    "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
1580 			    ieee80211_node_refcnt(ni));
1581 			/*
1582 			 * Send a deauthenticate frame and drop the station.
1583 			 * This is somewhat complicated due to reference counts
1584 			 * and locking.  At this point a station will typically
1585 			 * have a reference count of 1.  ieee80211_node_leave
1586 			 * will do a "free" of the node which will drop the
1587 			 * reference count.  But in the meantime a reference
1588 			 * wil be held by the deauth frame.  The actual reclaim
1589 			 * of the node will happen either after the tx is
1590 			 * completed or by ieee80211_node_leave.
1591 			 *
1592 			 * Separately we must drop the node lock before sending
1593 			 * in case the driver takes a lock, as this will result
1594 			 * in  LOR between the node lock and the driver lock.
1595 			 */
1596 			IEEE80211_NODE_UNLOCK(nt);
1597 			if (ni->ni_associd != 0) {
1598 				IEEE80211_SEND_MGMT(ic, ni,
1599 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
1600 				    IEEE80211_REASON_AUTH_EXPIRE);
1601 			}
1602 			ieee80211_node_leave(ic, ni);
1603 			ic->ic_stats.is_node_timeout++;
1604 			goto restart;
1605 		}
1606 	}
1607 	IEEE80211_NODE_UNLOCK(nt);
1608 
1609 	IEEE80211_SCAN_UNLOCK(nt);
1610 
1611 	nt->nt_inact_timer = IEEE80211_INACT_WAIT;
1612 }
1613 
1614 void
1615 ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
1616 {
1617 	struct ieee80211_node *ni;
1618 	u_int gen;
1619 
1620 	IEEE80211_SCAN_LOCK(nt);
1621 	gen = nt->nt_scangen++;
1622 restart:
1623 	IEEE80211_NODE_LOCK(nt);
1624 	TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1625 		if (ni->ni_scangen != gen) {
1626 			ni->ni_scangen = gen;
1627 			(void) ieee80211_ref_node(ni);
1628 			IEEE80211_NODE_UNLOCK(nt);
1629 			(*f)(arg, ni);
1630 			ieee80211_free_node(ni);
1631 			goto restart;
1632 		}
1633 	}
1634 	IEEE80211_NODE_UNLOCK(nt);
1635 
1636 	IEEE80211_SCAN_UNLOCK(nt);
1637 }
1638 
1639 void
1640 ieee80211_dump_node(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
1641 {
1642 	printf("0x%p: mac %s refcnt %d\n", ni,
1643 		ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
1644 	printf("\tscangen %u authmode %u flags 0x%x\n",
1645 		ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
1646 	printf("\tassocid 0x%x txpower %u vlan %u\n",
1647 		ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
1648 	printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
1649 		ni->ni_txseqs[0],
1650 		ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
1651 		ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
1652 		ni->ni_rxfragstamp);
1653 	printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
1654 		ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
1655 	printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
1656 		ether_sprintf(ni->ni_bssid),
1657 		ni->ni_esslen, ni->ni_essid,
1658 		ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
1659 	printf("\tfails %u inact %u txrate %u\n",
1660 		ni->ni_fails, ni->ni_inact, ni->ni_txrate);
1661 }
1662 
1663 void
1664 ieee80211_dump_nodes(struct ieee80211_node_table *nt)
1665 {
1666 	ieee80211_iterate_nodes(nt,
1667 		(ieee80211_iter_func *) ieee80211_dump_node, nt);
1668 }
1669 
1670 /*
1671  * Handle a station joining an 11g network.
1672  */
1673 static void
1674 ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1675 {
1676 
1677 	/*
1678 	 * Station isn't capable of short slot time.  Bump
1679 	 * the count of long slot time stations and disable
1680 	 * use of short slot time.  Note that the actual switch
1681 	 * over to long slot time use may not occur until the
1682 	 * next beacon transmission (per sec. 7.3.1.4 of 11g).
1683 	 */
1684 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1685 		ic->ic_longslotsta++;
1686 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1687 		    "[%s] station needs long slot time, count %d\n",
1688 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1689 		/* XXX vap's w/ conflicting needs won't work */
1690 		ieee80211_set_shortslottime(ic, 0);
1691 	}
1692 	/*
1693 	 * If the new station is not an ERP station
1694 	 * then bump the counter and enable protection
1695 	 * if configured.
1696 	 */
1697 	if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
1698 		ic->ic_nonerpsta++;
1699 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1700 		    "[%s] station is !ERP, %d non-ERP stations associated\n",
1701 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1702 		/*
1703 		 * If protection is configured, enable it.
1704 		 */
1705 		if (ic->ic_protmode != IEEE80211_PROT_NONE) {
1706 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1707 			    "%s: enable use of protection\n", __func__);
1708 			ic->ic_flags |= IEEE80211_F_USEPROT;
1709 		}
1710 		/*
1711 		 * If station does not support short preamble
1712 		 * then we must enable use of Barker preamble.
1713 		 */
1714 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
1715 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1716 			    "[%s] station needs long preamble\n",
1717 			    ether_sprintf(ni->ni_macaddr));
1718 			ic->ic_flags |= IEEE80211_F_USEBARKER;
1719 			ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
1720 		}
1721 	} else
1722 		ni->ni_flags |= IEEE80211_NODE_ERP;
1723 }
1724 
1725 void
1726 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
1727 {
1728 	int newassoc;
1729 
1730 	if (ni->ni_associd == 0) {
1731 		u_int16_t aid;
1732 
1733 		/*
1734 		 * It would be good to search the bitmap
1735 		 * more efficiently, but this will do for now.
1736 		 */
1737 		for (aid = 1; aid < ic->ic_max_aid; aid++) {
1738 			if (!IEEE80211_AID_ISSET(aid,
1739 			    ic->ic_aid_bitmap))
1740 				break;
1741 		}
1742 		if (aid >= ic->ic_max_aid) {
1743 			IEEE80211_SEND_MGMT(ic, ni, resp,
1744 			    IEEE80211_REASON_ASSOC_TOOMANY);
1745 			ieee80211_node_leave(ic, ni);
1746 			return;
1747 		}
1748 		ni->ni_associd = aid | 0xc000;
1749 		IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
1750 		ic->ic_sta_assoc++;
1751 		newassoc = 1;
1752 		if (ic->ic_curmode == IEEE80211_MODE_11G ||
1753 		    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1754 			ieee80211_node_join_11g(ic, ni);
1755 	} else
1756 		newassoc = 0;
1757 
1758 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1759 	    "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
1760 	    ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
1761 	    IEEE80211_NODE_AID(ni),
1762 	    ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
1763 	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
1764 	    ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
1765 	    ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
1766 	);
1767 
1768 	/* give driver a chance to setup state like ni_txrate */
1769 	if (ic->ic_newassoc != NULL)
1770 		ic->ic_newassoc(ic, ni, newassoc);
1771 	ni->ni_inact_reload = ic->ic_inact_auth;
1772 	ni->ni_inact = ni->ni_inact_reload;
1773 	IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
1774 	/* tell the authenticator about new station */
1775 	if (ic->ic_auth->ia_node_join != NULL)
1776 		ic->ic_auth->ia_node_join(ic, ni);
1777 	ieee80211_notify_node_join(ic, ni, newassoc);
1778 }
1779 
1780 /*
1781  * Handle a station leaving an 11g network.
1782  */
1783 static void
1784 ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
1785 {
1786 
1787 	IASSERT(ic->ic_curmode == IEEE80211_MODE_11G ||
1788 		ic->ic_curmode == IEEE80211_MODE_TURBO_G,
1789 		("not in 11g, curmode %x", ic->ic_curmode));
1790 
1791 	/*
1792 	 * If a long slot station do the slot time bookkeeping.
1793 	 */
1794 	if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
1795 		IASSERT(ic->ic_longslotsta > 0,
1796 		    ("bogus long slot station count %d", ic->ic_longslotsta));
1797 		ic->ic_longslotsta--;
1798 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1799 		    "[%s] long slot time station leaves, count now %d\n",
1800 		    ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
1801 		if (ic->ic_longslotsta == 0) {
1802 			/*
1803 			 * Re-enable use of short slot time if supported
1804 			 * and not operating in IBSS mode (per spec).
1805 			 */
1806 			if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
1807 			    ic->ic_opmode != IEEE80211_M_IBSS) {
1808 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1809 				    "%s: re-enable use of short slot time\n",
1810 				    __func__);
1811 				ieee80211_set_shortslottime(ic, 1);
1812 			}
1813 		}
1814 	}
1815 	/*
1816 	 * If a non-ERP station do the protection-related bookkeeping.
1817 	 */
1818 	if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
1819 		IASSERT(ic->ic_nonerpsta > 0,
1820 		    ("bogus non-ERP station count %d", ic->ic_nonerpsta));
1821 		ic->ic_nonerpsta--;
1822 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1823 		    "[%s] non-ERP station leaves, count now %d\n",
1824 		    ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
1825 		if (ic->ic_nonerpsta == 0) {
1826 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1827 				"%s: disable use of protection\n", __func__);
1828 			ic->ic_flags &= ~IEEE80211_F_USEPROT;
1829 			/* XXX verify mode? */
1830 			if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
1831 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1832 				    "%s: re-enable use of short preamble\n",
1833 				    __func__);
1834 				ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
1835 				ic->ic_flags &= ~IEEE80211_F_USEBARKER;
1836 			}
1837 		}
1838 	}
1839 }
1840 
1841 /*
1842  * Handle bookkeeping for station deauthentication/disassociation
1843  * when operating as an ap.
1844  */
1845 void
1846 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
1847 {
1848 	struct ieee80211_node_table *nt = ni->ni_table;
1849 
1850 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
1851 	    "[%s] station with aid %d leaves\n",
1852 	    ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
1853 
1854 	IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1855 		ic->ic_opmode == IEEE80211_M_IBSS ||
1856 		ic->ic_opmode == IEEE80211_M_AHDEMO,
1857 		("unexpected operating mode %u", ic->ic_opmode));
1858 	/*
1859 	 * If node wasn't previously associated all
1860 	 * we need to do is reclaim the reference.
1861 	 */
1862 	/* XXX ibss mode bypasses 11g and notification */
1863 	if (ni->ni_associd == 0)
1864 		goto done;
1865 	/*
1866 	 * Tell the authenticator the station is leaving.
1867 	 * Note that we must do this before yanking the
1868 	 * association id as the authenticator uses the
1869 	 * associd to locate it's state block.
1870 	 */
1871 	if (ic->ic_auth->ia_node_leave != NULL)
1872 		ic->ic_auth->ia_node_leave(ic, ni);
1873 	IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
1874 	ni->ni_associd = 0;
1875 	ic->ic_sta_assoc--;
1876 
1877 	if (ic->ic_curmode == IEEE80211_MODE_11G ||
1878 	    ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1879 		ieee80211_node_leave_11g(ic, ni);
1880 	/*
1881 	 * Cleanup station state.  In particular clear various
1882 	 * state that might otherwise be reused if the node
1883 	 * is reused before the reference count goes to zero
1884 	 * (and memory is reclaimed).
1885 	 */
1886 	ieee80211_sta_leave(ic, ni);
1887 done:
1888 	/*
1889 	 * Remove the node from any table it's recorded in and
1890 	 * drop the caller's reference.  Removal from the table
1891 	 * is important to insure the node is not reprocessed
1892 	 * for inactivity.
1893 	 */
1894 	if (nt != NULL) {
1895 		IEEE80211_NODE_LOCK(nt);
1896 		node_reclaim(nt, ni);
1897 		IEEE80211_NODE_UNLOCK(nt);
1898 	} else
1899 		ieee80211_free_node(ni);
1900 }
1901 
1902 u_int8_t
1903 ieee80211_getrssi(struct ieee80211com *ic)
1904 {
1905 #define	NZ(x)	((x) == 0 ? 1 : (x))
1906 	struct ieee80211_node_table *nt = &ic->ic_sta;
1907 	u_int32_t rssi_samples, rssi_total;
1908 	struct ieee80211_node *ni;
1909 
1910 	rssi_total = 0;
1911 	rssi_samples = 0;
1912 	switch (ic->ic_opmode) {
1913 	case IEEE80211_M_IBSS:		/* average of all ibss neighbors */
1914 		/* XXX locking */
1915 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
1916 			if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
1917 				rssi_samples++;
1918 				rssi_total += ic->ic_node_getrssi(ni);
1919 			}
1920 		break;
1921 	case IEEE80211_M_AHDEMO:	/* average of all neighbors */
1922 		/* XXX locking */
1923 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
1924 			rssi_samples++;
1925 			rssi_total += ic->ic_node_getrssi(ni);
1926 		}
1927 		break;
1928 	case IEEE80211_M_HOSTAP:	/* average of all associated stations */
1929 #ifndef IEEE80211_NO_HOSTAP
1930 		/* XXX locking */
1931 		TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
1932 			if (IEEE80211_AID(ni->ni_associd) != 0) {
1933 				rssi_samples++;
1934 				rssi_total += ic->ic_node_getrssi(ni);
1935 			}
1936 #endif /* !IEEE80211_NO_HOSTAP */
1937 		break;
1938 	case IEEE80211_M_MONITOR:	/* XXX */
1939 	case IEEE80211_M_STA:		/* use stats from associated ap */
1940 	default:
1941 		if (ic->ic_bss != NULL)
1942 			rssi_total = ic->ic_node_getrssi(ic->ic_bss);
1943 		rssi_samples = 1;
1944 		break;
1945 	}
1946 	return rssi_total / NZ(rssi_samples);
1947 #undef NZ
1948 }
1949 
1950 /*
1951  * Indicate whether there are frames queued for a station in power-save mode.
1952  */
1953 static void
1954 ieee80211_set_tim(struct ieee80211com *ic, struct ieee80211_node *ni, int set)
1955 {
1956 	u_int16_t aid;
1957 
1958 	IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
1959 		ic->ic_opmode == IEEE80211_M_IBSS,
1960 		("operating mode %u", ic->ic_opmode));
1961 
1962 	aid = IEEE80211_AID(ni->ni_associd);
1963 	IASSERT(aid < ic->ic_max_aid,
1964 		("bogus aid %u, max %u", aid, ic->ic_max_aid));
1965 
1966 	IEEE80211_BEACON_LOCK(ic);
1967 	if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
1968 		if (set) {
1969 			setbit(ic->ic_tim_bitmap, aid);
1970 			ic->ic_ps_pending++;
1971 		} else {
1972 			clrbit(ic->ic_tim_bitmap, aid);
1973 			ic->ic_ps_pending--;
1974 		}
1975 		ic->ic_flags |= IEEE80211_F_TIMUPDATE;
1976 	}
1977 	IEEE80211_BEACON_UNLOCK(ic);
1978 }
1979 
1980 /*
1981  * Node table support.
1982  */
1983 
1984 static void
1985 ieee80211_node_table_init(struct ieee80211com *ic,
1986 	struct ieee80211_node_table *nt,
1987 	const char *name, int inact,
1988 	void (*timeout)(struct ieee80211_node_table *))
1989 {
1990 
1991 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1992 		"%s %s table, inact %u\n", __func__, name, inact);
1993 
1994 	nt->nt_ic = ic;
1995 	/* XXX need unit */
1996 	IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1997 	IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
1998 	TAILQ_INIT(&nt->nt_node);
1999 	nt->nt_name = name;
2000 	nt->nt_scangen = 1;
2001 	nt->nt_inact_init = inact;
2002 	nt->nt_timeout = timeout;
2003 }
2004 
2005 void
2006 ieee80211_node_table_reset(struct ieee80211_node_table *nt)
2007 {
2008 
2009 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2010 		"%s %s table\n", __func__, nt->nt_name);
2011 
2012 	IEEE80211_NODE_LOCK(nt);
2013 	nt->nt_inact_timer = 0;
2014 	ieee80211_free_allnodes_locked(nt);
2015 	IEEE80211_NODE_UNLOCK(nt);
2016 }
2017 
2018 static void
2019 ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
2020 {
2021 
2022 	IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
2023 		"%s %s table\n", __func__, nt->nt_name);
2024 
2025 	ieee80211_free_allnodes_locked(nt);
2026 	IEEE80211_SCAN_LOCK_DESTROY(nt);
2027 	IEEE80211_NODE_LOCK_DESTROY(nt);
2028 }
2029