1 /* $NetBSD: ieee80211_node.c,v 1.10.2.1 2004/08/03 16:54:45 jmc Exp $ */
2 /*-
3 * Copyright (c) 2001 Atsushi Onoe
4 * Copyright (c) 2002, 2003 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 1.13 2003/11/09 23:36:46 sam Exp $");
37 #else
38 __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.10.2.1 2004/08/03 16:54:45 jmc Exp $");
39 #endif
40
41 #include "opt_inet.h"
42
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/mbuf.h>
46 #include <sys/malloc.h>
47 #include <sys/kernel.h>
48 #include <sys/socket.h>
49 #include <sys/sockio.h>
50 #include <sys/endian.h>
51 #include <sys/errno.h>
52 #ifdef __FreeBSD__
53 #include <sys/bus.h>
54 #endif
55 #include <sys/proc.h>
56 #include <sys/sysctl.h>
57
58 #ifdef __FreeBSD__
59 #include <machine/atomic.h>
60 #endif
61
62 #include <net/if.h>
63 #include <net/if_dl.h>
64 #include <net/if_media.h>
65 #include <net/if_arp.h>
66 #ifdef __FreeBSD__
67 #include <net/ethernet.h>
68 #else
69 #include <net/if_ether.h>
70 #endif
71 #include <net/if_llc.h>
72
73 #include <net80211/ieee80211_var.h>
74 #include <net80211/ieee80211_compat.h>
75
76 #include <net/bpf.h>
77
78 #ifdef INET
79 #include <netinet/in.h>
80 #ifdef __FreeBSD__
81 #include <netinet/if_ether.h>
82 #else
83 #include <net/if_ether.h>
84 #endif
85 #endif
86
87 static struct ieee80211_node *ieee80211_node_alloc(struct ieee80211com *);
88 static void ieee80211_node_free(struct ieee80211com *, struct ieee80211_node *);
89 static void ieee80211_node_copy(struct ieee80211com *,
90 struct ieee80211_node *, const struct ieee80211_node *);
91 static u_int8_t ieee80211_node_getrssi(struct ieee80211com *,
92 struct ieee80211_node *);
93
94 static void ieee80211_setup_node(struct ieee80211com *ic,
95 struct ieee80211_node *ni, u_int8_t *macaddr);
96 static void _ieee80211_free_node(struct ieee80211com *,
97 struct ieee80211_node *);
98
99 MALLOC_DEFINE(M_80211_NODE, "node", "802.11 node state");
100
101 void
102 ieee80211_node_attach(struct ifnet *ifp)
103 {
104 struct ieee80211com *ic = (void *)ifp;
105
106 #ifdef __FreeBSD__
107 /* XXX need unit */
108 IEEE80211_NODE_LOCK_INIT(ic, ifp->if_xname);
109 #endif
110 TAILQ_INIT(&ic->ic_node);
111 ic->ic_node_alloc = ieee80211_node_alloc;
112 ic->ic_node_free = ieee80211_node_free;
113 ic->ic_node_copy = ieee80211_node_copy;
114 ic->ic_node_getrssi = ieee80211_node_getrssi;
115 ic->ic_scangen = 1;
116 }
117
118 void
119 ieee80211_node_lateattach(struct ifnet *ifp)
120 {
121 struct ieee80211com *ic = (void *)ifp;
122
123 ic->ic_bss = (*ic->ic_node_alloc)(ic);
124 IASSERT(ic->ic_bss != NULL, ("unable to setup inital BSS node"));
125 ic->ic_bss->ni_chan = IEEE80211_CHAN_ANYC;
126 }
127
128 void
129 ieee80211_node_detach(struct ifnet *ifp)
130 {
131 struct ieee80211com *ic = (void *)ifp;
132
133 if (ic->ic_bss != NULL)
134 (*ic->ic_node_free)(ic, ic->ic_bss);
135 ieee80211_free_allnodes(ic);
136 #ifdef __FreeBSD__
137 IEEE80211_NODE_LOCK_DESTROY(ic);
138 #endif
139 }
140
141 /*
142 * AP scanning support.
143 */
144
145 /*
146 * Initialize the active channel set based on the set
147 * of available channels and the current PHY mode.
148 */
149 static void
150 ieee80211_reset_scan(struct ifnet *ifp)
151 {
152 struct ieee80211com *ic = (void *)ifp;
153
154 memcpy(ic->ic_chan_scan, ic->ic_chan_active,
155 sizeof(ic->ic_chan_active));
156 /* NB: hack, setup so next_scan starts with the first channel */
157 if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC)
158 ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX];
159 }
160
161 /*
162 * Begin an active scan.
163 */
164 void
165 ieee80211_begin_scan(struct ifnet *ifp)
166 {
167 struct ieee80211com *ic = (void *)ifp;
168
169 /*
170 * In all but hostap mode scanning starts off in
171 * an active mode before switching to passive.
172 */
173 if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
174 ic->ic_flags |= IEEE80211_F_ASCAN;
175 ic->ic_stats.is_scan_active++;
176 } else
177 ic->ic_stats.is_scan_passive++;
178 if (ifp->if_flags & IFF_DEBUG)
179 if_printf(ifp, "begin %s scan\n",
180 (ic->ic_flags & IEEE80211_F_ASCAN) ?
181 "active" : "passive");
182 /*
183 * Clear scan state and flush any previously seen
184 * AP's. Note that the latter assumes we don't act
185 * as both an AP and a station, otherwise we'll
186 * potentially flush state of stations associated
187 * with us.
188 */
189 ieee80211_reset_scan(ifp);
190 ieee80211_free_allnodes(ic);
191
192 /* Scan the next channel. */
193 ieee80211_next_scan(ifp);
194 }
195
196 /*
197 * Switch to the next channel marked for scanning.
198 */
199 void
200 ieee80211_next_scan(struct ifnet *ifp)
201 {
202 struct ieee80211com *ic = (void *)ifp;
203 struct ieee80211_channel *chan;
204
205 chan = ic->ic_bss->ni_chan;
206 for (;;) {
207 if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
208 chan = &ic->ic_channels[0];
209 if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
210 /*
211 * Honor channels marked passive-only
212 * during an active scan.
213 */
214 if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 ||
215 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0)
216 break;
217 }
218 if (chan == ic->ic_bss->ni_chan) {
219 ieee80211_end_scan(ifp);
220 return;
221 }
222 }
223 clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
224 IEEE80211_DPRINTF(("ieee80211_next_scan: chan %d->%d\n",
225 ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan),
226 ieee80211_chan2ieee(ic, chan)));
227 ic->ic_bss->ni_chan = chan;
228 ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
229 }
230
231 void
232 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
233 {
234 struct ieee80211_node *ni;
235 struct ifnet *ifp = &ic->ic_if;
236
237 ni = ic->ic_bss;
238 if (ifp->if_flags & IFF_DEBUG)
239 if_printf(ifp, "creating ibss\n");
240 ic->ic_flags |= IEEE80211_F_SIBSS;
241 ni->ni_chan = chan;
242 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
243 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr);
244 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
245 if (ic->ic_opmode == IEEE80211_M_IBSS)
246 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */
247 ni->ni_esslen = ic->ic_des_esslen;
248 memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
249 ni->ni_rssi = 0;
250 ni->ni_rstamp = 0;
251 memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp));
252 ni->ni_intval = ic->ic_lintval;
253 ni->ni_capinfo = IEEE80211_CAPINFO_IBSS;
254 if (ic->ic_flags & IEEE80211_F_WEPON)
255 ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
256 if (ic->ic_phytype == IEEE80211_T_FH) {
257 ni->ni_fhdwell = 200; /* XXX */
258 ni->ni_fhindex = 1;
259 }
260 ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
261 }
262
263 int
264 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
265 {
266 struct ifnet *ifp = &ic->ic_if;
267 u_int8_t rate;
268 int fail;
269
270 fail = 0;
271 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
272 fail |= 0x01;
273 if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
274 ni->ni_chan != ic->ic_des_chan)
275 fail |= 0x01;
276 if (ic->ic_opmode == IEEE80211_M_IBSS) {
277 if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
278 fail |= 0x02;
279 } else {
280 if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
281 fail |= 0x02;
282 }
283 if (ic->ic_flags & IEEE80211_F_WEPON) {
284 if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
285 fail |= 0x04;
286 } else {
287 if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
288 fail |= 0x04;
289 }
290 rate = ieee80211_fix_rate(ic, ni, IEEE80211_F_DONEGO);
291 if (rate & IEEE80211_RATE_BASIC)
292 fail |= 0x08;
293 if (ic->ic_des_esslen != 0 &&
294 (ni->ni_esslen != ic->ic_des_esslen ||
295 memcmp(ni->ni_essid, ic->ic_des_essid,
296 ic->ic_des_esslen != 0)))
297 fail |= 0x10;
298 if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
299 !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
300 fail |= 0x20;
301 if (ifp->if_flags & IFF_DEBUG) {
302 printf(" %c %s", fail ? '-' : '+',
303 ether_sprintf(ni->ni_macaddr));
304 printf(" %s%c", ether_sprintf(ni->ni_bssid),
305 fail & 0x20 ? '!' : ' ');
306 printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
307 fail & 0x01 ? '!' : ' ');
308 printf(" %+4d", ni->ni_rssi);
309 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
310 fail & 0x08 ? '!' : ' ');
311 printf(" %4s%c",
312 (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
313 (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
314 "????",
315 fail & 0x02 ? '!' : ' ');
316 printf(" %3s%c ",
317 (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
318 "wep" : "no",
319 fail & 0x04 ? '!' : ' ');
320 ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
321 printf("%s\n", fail & 0x10 ? "!" : "");
322 }
323 return fail;
324 }
325
326 /*
327 * Complete a scan of potential channels.
328 */
329 void
330 ieee80211_end_scan(struct ifnet *ifp)
331 {
332 struct ieee80211com *ic = (void *)ifp;
333 struct ieee80211_node *ni, *nextbs, *selbs;
334 int i, fail;
335
336 ic->ic_flags &= ~IEEE80211_F_ASCAN;
337 ni = TAILQ_FIRST(&ic->ic_node);
338
339 if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
340 /* XXX off stack? */
341 u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)];
342 /*
343 * The passive scan to look for existing AP's completed,
344 * select a channel to camp on. Identify the channels
345 * that already have one or more AP's and try to locate
346 * an unnoccupied one. If that fails, pick a random
347 * channel from the active set.
348 */
349 for (; ni != NULL; ni = nextbs) {
350 ieee80211_ref_node(ni);
351 nextbs = TAILQ_NEXT(ni, ni_list);
352 setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan));
353 ieee80211_free_node(ic, ni);
354 }
355 for (i = 0; i < IEEE80211_CHAN_MAX; i++)
356 if (isset(ic->ic_chan_active, i) && isclr(occupied, i))
357 break;
358 if (i == IEEE80211_CHAN_MAX) {
359 fail = arc4random() & 3; /* random 0-3 */
360 for (i = 0; i < IEEE80211_CHAN_MAX; i++)
361 if (isset(ic->ic_chan_active, i) && fail-- == 0)
362 break;
363 }
364 ieee80211_create_ibss(ic, &ic->ic_channels[i]);
365 return;
366 }
367 if (ni == NULL) {
368 IEEE80211_DPRINTF(("%s: no scan candidate\n", __func__));
369 notfound:
370 if (ic->ic_opmode == IEEE80211_M_IBSS &&
371 (ic->ic_flags & IEEE80211_F_IBSSON) &&
372 ic->ic_des_esslen != 0) {
373 ieee80211_create_ibss(ic, ic->ic_ibss_chan);
374 return;
375 }
376 /*
377 * Reset the list of channels to scan and start again.
378 */
379 ieee80211_reset_scan(ifp);
380 ieee80211_next_scan(ifp);
381 return;
382 }
383 selbs = NULL;
384 if (ifp->if_flags & IFF_DEBUG)
385 if_printf(ifp, "\tmacaddr bssid chan rssi rate flag wep essid\n");
386 for (; ni != NULL; ni = nextbs) {
387 ieee80211_ref_node(ni);
388 nextbs = TAILQ_NEXT(ni, ni_list);
389 if (ni->ni_fails) {
390 /*
391 * The configuration of the access points may change
392 * during my scan. So delete the entry for the AP
393 * and retry to associate if there is another beacon.
394 */
395 if (ni->ni_fails++ > 2)
396 ieee80211_free_node(ic, ni);
397 continue;
398 }
399 if (ieee80211_match_bss(ic, ni) == 0) {
400 if (selbs == NULL)
401 selbs = ni;
402 else if (ni->ni_rssi > selbs->ni_rssi) {
403 ieee80211_unref_node(&selbs);
404 selbs = ni;
405 } else
406 ieee80211_unref_node(&ni);
407 } else {
408 ieee80211_unref_node(&ni);
409 }
410 }
411 if (selbs == NULL)
412 goto notfound;
413 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs);
414 if (ic->ic_opmode == IEEE80211_M_IBSS) {
415 ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE |
416 IEEE80211_F_DONEGO | IEEE80211_F_DODEL);
417 if (ic->ic_bss->ni_rates.rs_nrates == 0) {
418 selbs->ni_fails++;
419 ieee80211_unref_node(&selbs);
420 goto notfound;
421 }
422 ieee80211_unref_node(&selbs);
423 ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
424 } else {
425 ieee80211_unref_node(&selbs);
426 ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
427 }
428 }
429
430 int
431 ieee80211_get_rate(struct ieee80211com *ic)
432 {
433 u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE];
434 int rate;
435
436 rates = &ic->ic_bss->ni_rates.rs_rates;
437
438 if (ic->ic_fixed_rate != -1)
439 rate = (*rates)[ic->ic_fixed_rate];
440 else if (ic->ic_state == IEEE80211_S_RUN)
441 rate = (*rates)[ic->ic_bss->ni_txrate];
442 else
443 rate = 0;
444
445 return rate & IEEE80211_RATE_VAL;
446 }
447
448 static struct ieee80211_node *
449 ieee80211_node_alloc(struct ieee80211com *ic)
450 {
451 return malloc(sizeof(struct ieee80211_node), M_80211_NODE,
452 M_NOWAIT | M_ZERO);
453 }
454
455 static void
456 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni)
457 {
458 if (ni->ni_challenge != NULL) {
459 free(ni->ni_challenge, M_DEVBUF);
460 ni->ni_challenge = NULL;
461 }
462 free(ni, M_80211_NODE);
463 }
464
465 static void
466 ieee80211_node_copy(struct ieee80211com *ic,
467 struct ieee80211_node *dst, const struct ieee80211_node *src)
468 {
469 *dst = *src;
470 dst->ni_challenge = NULL;
471 }
472
473 static u_int8_t
474 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni)
475 {
476 return ni->ni_rssi;
477 }
478
479 static void
480 ieee80211_setup_node(struct ieee80211com *ic,
481 struct ieee80211_node *ni, u_int8_t *macaddr)
482 {
483 int hash;
484 ieee80211_node_critsec_decl(s);
485
486 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
487 hash = IEEE80211_NODE_HASH(macaddr);
488 ni->ni_refcnt = 1; /* mark referenced */
489 ieee80211_node_critsec_begin(ic, s);
490 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list);
491 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash);
492 /*
493 * Note we don't enable the inactive timer when acting
494 * as a station. Nodes created in this mode represent
495 * AP's identified while scanning. If we time them out
496 * then several things happen: we can't return the data
497 * to users to show the list of AP's we encountered, and
498 * more importantly, we'll incorrectly deauthenticate
499 * ourself because the inactivity timer will kick us off.
500 */
501 if (ic->ic_opmode != IEEE80211_M_STA)
502 ic->ic_inact_timer = IEEE80211_INACT_WAIT;
503 ieee80211_node_critsec_end(ic, s);
504 }
505
506 struct ieee80211_node *
507 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr)
508 {
509 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic);
510 if (ni != NULL)
511 ieee80211_setup_node(ic, ni, macaddr);
512 return ni;
513 }
514
515 struct ieee80211_node *
516 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr)
517 {
518 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic);
519 if (ni != NULL) {
520 memcpy(ni, ic->ic_bss, sizeof(struct ieee80211_node));
521 ieee80211_setup_node(ic, ni, macaddr);
522 }
523 return ni;
524 }
525
526 struct ieee80211_node *
527 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr)
528 {
529 struct ieee80211_node *ni;
530 int hash;
531 ieee80211_node_critsec_decl(s);
532
533 hash = IEEE80211_NODE_HASH(macaddr);
534 ieee80211_node_critsec_begin(ic, s);
535 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) {
536 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
537 ieee80211_node_incref(ni); /* mark referenced */
538 break;
539 }
540 }
541 ieee80211_node_critsec_end(ic, s);
542 return ni;
543 }
544
545 struct ieee80211_node *
546 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr)
547 {
548 struct ieee80211_node *ni;
549 ieee80211_node_critsec_decl(s);
550
551 /*
552 * The destination address should be in the node table
553 * unless this is a multicast/broadcast frames or we are
554 * in station mode.
555 */
556 if (IEEE80211_IS_MULTICAST(macaddr) || ic->ic_opmode == IEEE80211_M_STA)
557 return ic->ic_bss;
558
559 ieee80211_node_critsec_begin(ic, s);
560 ni = ieee80211_find_node(ic, macaddr);
561 if (ni == NULL) {
562 if (ic->ic_opmode != IEEE80211_M_MONITOR)
563 ni = ieee80211_dup_bss(ic, macaddr);
564 IEEE80211_DPRINTF(("%s: faked-up node %p for %s\n",
565 __func__, ni, ether_sprintf(macaddr)));
566 if (ni == NULL) {
567 ieee80211_node_critsec_end(ic, s);
568 /* ic->ic_stats.st_tx_nonode++; XXX statistic */
569 return NULL;
570 }
571 (void)ieee80211_ref_node(ni);
572 }
573 ieee80211_node_critsec_end(ic, s);
574 return ni;
575 }
576
577 /*
578 * For some types of packet and for some operating modes, it is
579 * desirable to process a Rx packet using its sender's node-record
580 * instead of the BSS record, when that is possible.
581 *
582 * - AP mode: it is desirable to keep a node-record for every
583 * authenticated/associated station *in the BSS*. For future use,
584 * we also track neighboring APs, since they might belong to the
585 * same ESSID.
586 *
587 * - IBSS mode: it is desirable to keep a node-record for every
588 * station *in the BSS*.
589 *
590 * - monitor mode: it is desirable to keep a node-record for every
591 * sender, regardless of BSS.
592 *
593 * - STA mode: the only available node-record is the BSS record,
594 * ic->ic_bss.
595 *
596 * Of all the 802.11 Control packets, only the node-records for
597 * RTS packets node-record can be looked up.
598 *
599 * Return non-zero if the packet's node-record is kept, zero
600 * otherwise.
601 */
602 static __inline int
603 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh,
604 u_int8_t **bssid)
605 {
606 struct ieee80211_node *bss = ic->ic_bss;
607 int needsnode, rc = 0;
608
609 if (ic->ic_opmode == IEEE80211_M_STA)
610 return 0;
611
612 needsnode = (ic->ic_opmode == IEEE80211_M_MONITOR);
613
614 *bssid = NULL;
615
616 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
617 case IEEE80211_FC0_TYPE_CTL:
618 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) ==
619 IEEE80211_FC0_SUBTYPE_RTS;
620
621 case IEEE80211_FC0_TYPE_MGT:
622 *bssid = wh->i_addr3;
623 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid);
624 break;
625 case IEEE80211_FC0_TYPE_DATA:
626 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
627 case IEEE80211_FC1_DIR_NODS:
628 *bssid = wh->i_addr3;
629 if (ic->ic_opmode == IEEE80211_M_IBSS ||
630 ic->ic_opmode == IEEE80211_M_AHDEMO)
631 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid);
632 break;
633 case IEEE80211_FC1_DIR_TODS:
634 *bssid = wh->i_addr1;
635 if (ic->ic_opmode == IEEE80211_M_HOSTAP)
636 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid);
637 break;
638 case IEEE80211_FC1_DIR_FROMDS:
639 case IEEE80211_FC1_DIR_DSTODS:
640 *bssid = wh->i_addr2;
641 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP);
642 break;
643 }
644 break;
645 }
646 return needsnode || rc;
647 }
648
649 struct ieee80211_node *
650 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh)
651 {
652 struct ieee80211_node *ni;
653 const static u_int8_t zero[IEEE80211_ADDR_LEN];
654 u_int8_t *bssid;
655 ieee80211_node_critsec_decl(s);
656
657 ieee80211_node_critsec_begin(ic, s);
658
659 if (!ieee80211_needs_rxnode(ic, wh, &bssid))
660 return ieee80211_ref_node(ic->ic_bss);
661
662 ni = ieee80211_find_node(ic, wh->i_addr2);
663
664 if (ni == NULL) {
665 if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
666 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) != NULL)
667 IEEE80211_ADDR_COPY(ni->ni_bssid,
668 (bssid != NULL) ? bssid : zero);
669
670 IEEE80211_DPRINTF(("%s: faked-up node %p for %s\n",
671 __func__, ni, ether_sprintf(wh->i_addr2)));
672 }
673 ni = ieee80211_ref_node((ni == NULL) ? ic->ic_bss : ni);
674 }
675 ieee80211_node_critsec_end(ic, s);
676 IASSERT(ni != NULL, ("%s: null node", __func__));
677 return ni;
678 }
679
680 /*
681 * Like find but search based on the channel too.
682 */
683 struct ieee80211_node *
684 ieee80211_lookup_node(struct ieee80211com *ic,
685 u_int8_t *macaddr, struct ieee80211_channel *chan)
686 {
687 struct ieee80211_node *ni;
688 int hash;
689 ieee80211_node_critsec_decl(s);
690
691 hash = IEEE80211_NODE_HASH(macaddr);
692 ieee80211_node_critsec_begin(ic, s);
693 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) {
694 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
695 ni->ni_chan == chan) {
696 ieee80211_node_incref(ni);/* mark referenced */
697 break;
698 }
699 }
700 ieee80211_node_critsec_end(ic, s);
701 return ni;
702 }
703
704 /*
705 * Like find but search based on the channel and ssid too.
706 */
707 struct ieee80211_node *
708 ieee80211_lookup_node_for_beacon(struct ieee80211com *ic,
709 u_int8_t *macaddr, struct ieee80211_channel *chan, char *ssid)
710 {
711 struct ieee80211_node *ni;
712 int hash;
713 ieee80211_node_critsec_decl(s);
714
715 hash = IEEE80211_NODE_HASH(macaddr);
716 ieee80211_node_critsec_begin(ic, s);
717 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) {
718 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
719 ni->ni_chan == chan &&
720 (ssid[1] == 0 || (ssid[1] == ni->ni_esslen &&
721 !memcmp(ssid + 2, ni->ni_essid, ssid[1])))) {
722 ieee80211_node_incref(ni);/* mark referenced */
723 break;
724 }
725 }
726 ieee80211_node_critsec_end(ic, s);
727 return ni;
728 }
729
730 static void
731 _ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni)
732 {
733 IASSERT(ni != ic->ic_bss, ("freeing bss node"));
734
735 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
736 TAILQ_REMOVE(&ic->ic_node, ni, ni_list);
737 LIST_REMOVE(ni, ni_hash);
738 if (!IF_IS_EMPTY(&ni->ni_savedq)) {
739 IF_PURGE(&ni->ni_savedq);
740 if (ic->ic_set_tim)
741 ic->ic_set_tim(ic, ni->ni_associd, 0);
742 }
743 if (TAILQ_EMPTY(&ic->ic_node))
744 ic->ic_inact_timer = 0;
745 (*ic->ic_node_free)(ic, ni);
746 }
747
748 void
749 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni)
750 {
751 ieee80211_node_critsec_decl(s);
752
753 IASSERT(ni != ic->ic_bss, ("freeing ic_bss"));
754
755 if (ieee80211_node_decref(ni) == 0) {
756 ieee80211_node_critsec_begin(ic, s);
757 _ieee80211_free_node(ic, ni);
758 ieee80211_node_critsec_end(ic, s);
759 }
760 }
761
762 void
763 ieee80211_free_allnodes(struct ieee80211com *ic)
764 {
765 struct ieee80211_node *ni;
766 ieee80211_node_critsec_decl(s);
767
768 ieee80211_node_critsec_begin(ic, s);
769 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL)
770 _ieee80211_free_node(ic, ni);
771 ieee80211_node_critsec_end(ic, s);
772 }
773
774 /*
775 * Timeout inactive nodes. Note that we cannot hold the node
776 * lock while sending a frame as this would lead to a LOR.
777 * Instead we use a generation number to mark nodes that we've
778 * scanned and drop the lock and restart a scan if we have to
779 * time out a node. Since we are single-threaded by virtue of
780 * controlling the inactivity timer we can be sure this will
781 * process each node only once.
782 */
783 void
784 ieee80211_timeout_nodes(struct ieee80211com *ic)
785 {
786 struct ieee80211_node *ni;
787 ieee80211_node_critsec_decl(s);
788 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/
789
790 restart:
791 ieee80211_node_critsec_begin(ic, s);
792 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
793 if (ni->ni_scangen == gen) /* previously handled */
794 continue;
795 ni->ni_scangen = gen;
796 if (++ni->ni_inact > IEEE80211_INACT_MAX) {
797 IEEE80211_DPRINTF(("station %s timed out "
798 "due to inactivity (%u secs)\n",
799 ether_sprintf(ni->ni_macaddr),
800 ni->ni_inact));
801 /*
802 * Send a deauthenticate frame.
803 *
804 * Drop the node lock before sending the
805 * deauthentication frame in case the driver takes
806 * a lock, as this will result in a LOR between the
807 * node lock and the driver lock.
808 */
809 ieee80211_node_critsec_end(ic, s);
810 IEEE80211_SEND_MGMT(ic, ni,
811 IEEE80211_FC0_SUBTYPE_DEAUTH,
812 IEEE80211_REASON_AUTH_EXPIRE);
813 ieee80211_free_node(ic, ni);
814 ic->ic_stats.is_node_timeout++;
815 goto restart;
816 }
817 }
818 if (!TAILQ_EMPTY(&ic->ic_node))
819 ic->ic_inact_timer = IEEE80211_INACT_WAIT;
820 ieee80211_node_critsec_end(ic, s);
821 }
822
823 void
824 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg)
825 {
826 struct ieee80211_node *ni;
827 ieee80211_node_critsec_decl(s);
828
829 ieee80211_node_critsec_begin(ic, s);
830 TAILQ_FOREACH(ni, &ic->ic_node, ni_list)
831 (*f)(arg, ni);
832 ieee80211_node_critsec_end(ic, s);
833 }
Cache object: 234ce92a18691507e4b51a4f250b5aa8
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