1 /* $NetBSD: ieee80211_node.c,v 1.38 2005/02/26 22:45:09 perry Exp $ */
2 /*-
3 * Copyright (c) 2001 Atsushi Onoe
4 * Copyright (c) 2002-2004 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 1.22 2004/04/05 04:15:55 sam Exp $");
37 #else
38 __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.38 2005/02/26 22:45:09 perry 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, "80211node", "802.11 node state");
100
101 void
102 ieee80211_node_attach(struct ieee80211com *ic)
103 {
104
105 /* XXX need unit */
106 IEEE80211_NODE_LOCK_INIT(ic, ic->ic_ifp->if_xname);
107 TAILQ_INIT(&ic->ic_node);
108 ic->ic_node_alloc = ieee80211_node_alloc;
109 ic->ic_node_free = ieee80211_node_free;
110 ic->ic_node_copy = ieee80211_node_copy;
111 ic->ic_node_getrssi = ieee80211_node_getrssi;
112 ic->ic_scangen = 1;
113 ic->ic_max_nnodes = ieee80211_cache_size;
114
115 if (ic->ic_max_aid == 0)
116 ic->ic_max_aid = IEEE80211_AID_DEF;
117 else if (ic->ic_max_aid > IEEE80211_AID_MAX)
118 ic->ic_max_aid = IEEE80211_AID_MAX;
119 MALLOC(ic->ic_aid_bitmap, u_int32_t *,
120 howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t),
121 M_DEVBUF, M_NOWAIT | M_ZERO);
122 if (ic->ic_aid_bitmap == NULL) {
123 /* XXX no way to recover */
124 printf("%s: no memory for AID bitmap!\n", __func__);
125 ic->ic_max_aid = 0;
126 }
127 }
128
129 static struct ieee80211_node *
130 ieee80211_alloc_node_helper(struct ieee80211com *ic)
131 {
132 struct ieee80211_node *ni;
133 if (ic->ic_nnodes >= ic->ic_max_nnodes)
134 ieee80211_clean_nodes(ic);
135 if (ic->ic_nnodes >= ic->ic_max_nnodes)
136 return NULL;
137 ni = (*ic->ic_node_alloc)(ic);
138 if (ni != NULL)
139 ic->ic_nnodes++;
140 return ni;
141 }
142
143 void
144 ieee80211_node_lateattach(struct ieee80211com *ic)
145 {
146 struct ieee80211_node *ni;
147
148 ni = ieee80211_alloc_node_helper(ic);
149 IASSERT(ni != NULL, ("unable to setup inital BSS node"));
150 ni->ni_chan = IEEE80211_CHAN_ANYC;
151 ic->ic_bss = ieee80211_ref_node(ni);
152 ic->ic_txpower = IEEE80211_TXPOWER_MAX;
153 }
154
155 void
156 ieee80211_node_detach(struct ieee80211com *ic)
157 {
158
159 if (ic->ic_bss != NULL) {
160 (*ic->ic_node_free)(ic, ic->ic_bss);
161 ic->ic_bss = NULL;
162 }
163 ieee80211_free_allnodes(ic);
164 IEEE80211_NODE_LOCK_DESTROY(ic);
165 if (ic->ic_aid_bitmap != NULL)
166 FREE(ic->ic_aid_bitmap, M_DEVBUF);
167 }
168
169 /*
170 * AP scanning support.
171 */
172
173 /*
174 * Initialize the active channel set based on the set
175 * of available channels and the current PHY mode.
176 */
177 static void
178 ieee80211_reset_scan(struct ieee80211com *ic)
179 {
180
181 memcpy(ic->ic_chan_scan, ic->ic_chan_active,
182 sizeof(ic->ic_chan_active));
183 /* NB: hack, setup so next_scan starts with the first channel */
184 if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC)
185 ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX];
186 }
187
188 /*
189 * Begin an active scan.
190 */
191 void
192 ieee80211_begin_scan(struct ieee80211com *ic)
193 {
194
195 /*
196 * In all but hostap mode scanning starts off in
197 * an active mode before switching to passive.
198 */
199 if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
200 ic->ic_flags |= IEEE80211_F_ASCAN;
201 ic->ic_stats.is_scan_active++;
202 } else
203 ic->ic_stats.is_scan_passive++;
204 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("begin %s scan\n",
205 (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive"));
206 /*
207 * Clear scan state and flush any previously seen
208 * AP's. Note that the latter assumes we don't act
209 * as both an AP and a station, otherwise we'll
210 * potentially flush state of stations associated
211 * with us.
212 */
213 ieee80211_reset_scan(ic);
214 ieee80211_free_allnodes(ic);
215
216 /* Scan the next channel. */
217 ieee80211_next_scan(ic);
218 }
219
220 /*
221 * Switch to the next channel marked for scanning.
222 */
223 void
224 ieee80211_next_scan(struct ieee80211com *ic)
225 {
226 struct ieee80211_channel *chan;
227
228 chan = ic->ic_bss->ni_chan;
229 for (;;) {
230 if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
231 chan = &ic->ic_channels[0];
232 if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
233 /*
234 * Honor channels marked passive-only
235 * during an active scan.
236 */
237 if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 ||
238 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0)
239 break;
240 }
241 if (chan == ic->ic_bss->ni_chan) {
242 ieee80211_end_scan(ic);
243 return;
244 }
245 }
246 clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
247 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
248 ("%s: chan %d->%d\n", __func__,
249 ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan),
250 ieee80211_chan2ieee(ic, chan)));
251 ic->ic_bss->ni_chan = chan;
252 ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
253 }
254
255 void
256 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
257 {
258 struct ieee80211_node *ni;
259
260 ni = ic->ic_bss;
261 ic->ic_flags |= IEEE80211_F_SIBSS;
262 ni->ni_chan = chan;
263 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
264 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr);
265 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
266 if (ic->ic_opmode == IEEE80211_M_IBSS) {
267 if ((ic->ic_flags & IEEE80211_F_DESBSSID) != 0)
268 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
269 else
270 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */
271 }
272 if_printf(&ic->ic_if, "creating bss %s\n", ether_sprintf(ni->ni_bssid));
273 ni->ni_esslen = ic->ic_des_esslen;
274 memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
275 ni->ni_rssi = 0;
276 ni->ni_rstamp = 0;
277 memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp));
278 ni->ni_intval = ic->ic_lintval;
279 ni->ni_capinfo = IEEE80211_CAPINFO_IBSS;
280 if (ic->ic_flags & IEEE80211_F_PRIVACY)
281 ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
282 if (ic->ic_phytype == IEEE80211_T_FH) {
283 ni->ni_fhdwell = 200; /* XXX */
284 ni->ni_fhindex = 1;
285 }
286 ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
287 }
288
289 int
290 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
291 {
292 u_int8_t rate;
293 int fail;
294
295 fail = 0;
296 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
297 fail |= 0x01;
298 if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
299 ni->ni_chan != ic->ic_des_chan)
300 fail |= 0x01;
301 if (ic->ic_opmode == IEEE80211_M_IBSS) {
302 if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
303 fail |= 0x02;
304 } else {
305 if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
306 fail |= 0x02;
307 }
308 if (ic->ic_flags & IEEE80211_F_PRIVACY) {
309 if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
310 fail |= 0x04;
311 } else {
312 /* XXX does this mean privacy is supported or required? */
313 if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
314 fail |= 0x04;
315 }
316 rate = ieee80211_fix_rate(ic, ni, IEEE80211_F_DONEGO);
317 if (rate & IEEE80211_RATE_BASIC)
318 fail |= 0x08;
319 if (ic->ic_des_esslen != 0 &&
320 (ni->ni_esslen != ic->ic_des_esslen ||
321 memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
322 fail |= 0x10;
323 if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
324 !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
325 fail |= 0x20;
326 #ifdef IEEE80211_DEBUG
327 if (ic->ic_if.if_flags & IFF_DEBUG) {
328 printf(" %c %s", fail ? '-' : '+',
329 ether_sprintf(ni->ni_macaddr));
330 printf(" %s%c", ether_sprintf(ni->ni_bssid),
331 fail & 0x20 ? '!' : ' ');
332 printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
333 fail & 0x01 ? '!' : ' ');
334 printf(" %+4d", ni->ni_rssi);
335 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
336 fail & 0x08 ? '!' : ' ');
337 printf(" %4s%c",
338 (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
339 (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
340 "????",
341 fail & 0x02 ? '!' : ' ');
342 printf(" %3s%c ",
343 (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
344 "wep" : "no",
345 fail & 0x04 ? '!' : ' ');
346 ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
347 printf("%s\n", fail & 0x10 ? "!" : "");
348 }
349 #endif
350 return fail;
351 }
352
353 /*
354 * Complete a scan of potential channels.
355 */
356 void
357 ieee80211_end_scan(struct ieee80211com *ic)
358 {
359 struct ieee80211_node *ni, *nextbs, *selbs;
360 int i, fail;
361
362 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("end %s scan\n",
363 (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive"));
364
365 ic->ic_flags &= ~IEEE80211_F_ASCAN;
366 ni = TAILQ_FIRST(&ic->ic_node);
367
368 if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
369 /* XXX off stack? */
370 u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)];
371 /*
372 * The passive scan to look for existing AP's completed,
373 * select a channel to camp on. Identify the channels
374 * that already have one or more AP's and try to locate
375 * an unnoccupied one. If that fails, pick a random
376 * channel from the active set.
377 */
378 for (; ni != NULL; ni = nextbs) {
379 nextbs = TAILQ_NEXT(ni, ni_list);
380 setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan));
381 }
382 for (i = 0; i < IEEE80211_CHAN_MAX; i++)
383 if (isset(ic->ic_chan_active, i) && isclr(occupied, i))
384 break;
385 if (i == IEEE80211_CHAN_MAX) {
386 fail = arc4random() & 3; /* random 0-3 */
387 for (i = 0; i < IEEE80211_CHAN_MAX; i++)
388 if (isset(ic->ic_chan_active, i) && fail-- == 0)
389 break;
390 }
391 ieee80211_create_ibss(ic, &ic->ic_channels[i]);
392 return;
393 }
394 if (ni == NULL) {
395 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
396 ("%s: no scan candidate\n", __func__));
397 notfound:
398 if (ic->ic_opmode == IEEE80211_M_IBSS &&
399 (ic->ic_flags & IEEE80211_F_IBSSON) &&
400 ic->ic_des_esslen != 0) {
401 ieee80211_create_ibss(ic, ic->ic_ibss_chan);
402 return;
403 }
404 /*
405 * Reset the list of channels to scan and start again.
406 */
407 ieee80211_reset_scan(ic);
408 ieee80211_next_scan(ic);
409 return;
410 }
411 selbs = NULL;
412 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
413 ("\tmacaddr bssid chan rssi rate flag wep essid\n"));
414 for (; ni != NULL; ni = nextbs) {
415 nextbs = TAILQ_NEXT(ni, ni_list);
416 if (ni->ni_fails) {
417 /*
418 * The configuration of the access points may change
419 * during my scan. So delete the entry for the AP
420 * and retry to associate if there is another beacon.
421 */
422 if (ni->ni_fails++ > 2)
423 ieee80211_free_node(ic, ni);
424 continue;
425 }
426 if (ieee80211_match_bss(ic, ni) == 0) {
427 if (selbs == NULL)
428 selbs = ni;
429 else if (ni->ni_rssi > selbs->ni_rssi)
430 selbs = ni;
431 }
432 }
433 if (selbs == NULL)
434 goto notfound;
435 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs);
436 ieee80211_node_newstate(ic->ic_bss, IEEE80211_STA_BSS);
437 if (ic->ic_opmode == IEEE80211_M_IBSS) {
438 ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE |
439 IEEE80211_F_DONEGO | IEEE80211_F_DODEL);
440 if (ic->ic_bss->ni_rates.rs_nrates == 0)
441 goto notfound;
442 ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
443 } else {
444 ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
445 }
446 }
447
448 int
449 ieee80211_get_rate(struct ieee80211com *ic)
450 {
451 u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE];
452 int rate;
453
454 rates = &ic->ic_bss->ni_rates.rs_rates;
455
456 if (ic->ic_fixed_rate != -1)
457 rate = (*rates)[ic->ic_fixed_rate];
458 else if (ic->ic_state == IEEE80211_S_RUN)
459 rate = (*rates)[ic->ic_bss->ni_txrate];
460 else
461 rate = 0;
462
463 return rate & IEEE80211_RATE_VAL;
464 }
465
466 static struct ieee80211_node *
467 ieee80211_node_alloc(struct ieee80211com *ic)
468 {
469 struct ieee80211_node *ni;
470 MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
471 M_80211_NODE, M_NOWAIT | M_ZERO);
472 return ni;
473 }
474
475 static void
476 node_cleanup(struct ieee80211com *ic, struct ieee80211_node *ni)
477 {
478 if (ni->ni_challenge != NULL) {
479 FREE(ni->ni_challenge, M_DEVBUF);
480 ni->ni_challenge = NULL;
481 }
482 }
483
484 static void
485 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni)
486 {
487 node_cleanup(ic, ni);
488 FREE(ni, M_80211_NODE);
489 }
490
491 static void
492 ieee80211_node_copy(struct ieee80211com *ic,
493 struct ieee80211_node *dst, const struct ieee80211_node *src)
494 {
495 node_cleanup(ic, dst);
496 *dst = *src;
497 dst->ni_challenge = NULL;
498 }
499
500 static u_int8_t
501 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni)
502 {
503 return ni->ni_rssi;
504 }
505
506 static void
507 ieee80211_setup_node(struct ieee80211com *ic,
508 struct ieee80211_node *ni, u_int8_t *macaddr)
509 {
510 int hash;
511
512 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
513 ("%s %s\n", __func__, ether_sprintf(macaddr)));
514 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
515 hash = IEEE80211_NODE_HASH(macaddr);
516 ieee80211_node_newstate(ni, IEEE80211_STA_CACHE);
517
518 IEEE80211_NODE_LOCK_BH(ic);
519 /*
520 * Note we don't enable the inactive timer when acting
521 * as a station. Nodes created in this mode represent
522 * AP's identified while scanning. If we time them out
523 * then several things happen: we can't return the data
524 * to users to show the list of AP's we encountered, and
525 * more importantly, we'll incorrectly deauthenticate
526 * ourself because the inactivity timer will kick us off.
527 */
528 if (ic->ic_opmode != IEEE80211_M_STA &&
529 TAILQ_EMPTY(&ic->ic_node))
530 ic->ic_inact_timer = IEEE80211_INACT_WAIT;
531 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list);
532 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash);
533 IEEE80211_NODE_UNLOCK_BH(ic);
534 }
535
536 struct ieee80211_node *
537 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr)
538 {
539 struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic);
540 if (ni != NULL) {
541 ieee80211_setup_node(ic, ni, macaddr);
542 } else
543 ic->ic_stats.is_rx_nodealloc++;
544 return ni;
545 }
546
547 struct ieee80211_node *
548 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr)
549 {
550 struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic);
551 if (ni != NULL) {
552 ieee80211_setup_node(ic, ni, macaddr);
553 /*
554 * Inherit from ic_bss.
555 */
556 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
557 ni->ni_chan = ic->ic_bss->ni_chan;
558 } else
559 ic->ic_stats.is_rx_nodealloc++;
560 return ni;
561 }
562
563 static struct ieee80211_node *
564 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr)
565 {
566 struct ieee80211_node *ni;
567 int hash;
568
569 IEEE80211_NODE_LOCK_ASSERT(ic);
570
571 hash = IEEE80211_NODE_HASH(macaddr);
572 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) {
573 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
574 /* least-recently used is at tail */
575 TAILQ_REMOVE(&ic->ic_node, ni, ni_list);
576 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list);
577 return ni;
578 }
579 }
580 return NULL;
581 }
582
583 struct ieee80211_node *
584 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr)
585 {
586 struct ieee80211_node *ni;
587
588 IEEE80211_NODE_LOCK(ic);
589 ni = _ieee80211_find_node(ic, macaddr);
590 IEEE80211_NODE_UNLOCK(ic);
591 return ni;
592 }
593
594 /*
595 * Return a reference to the appropriate node for sending
596 * a data frame. This handles node discovery in adhoc networks.
597 *
598 * Drivers will call this, so increase the reference count before
599 * returning the node.
600 */
601 struct ieee80211_node *
602 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr)
603 {
604 struct ieee80211_node *ni;
605
606 /*
607 * The destination address should be in the node table
608 * unless we are operating in station mode or this is a
609 * multicast/broadcast frame.
610 */
611 if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
612 return ieee80211_ref_node(ic->ic_bss);
613
614 /* XXX can't hold lock across dup_bss 'cuz of recursive locking */
615 IEEE80211_NODE_LOCK(ic);
616 ni = _ieee80211_find_node(ic, macaddr);
617 IEEE80211_NODE_UNLOCK(ic);
618 if (ni == NULL) {
619 if (ic->ic_opmode != IEEE80211_M_IBSS &&
620 ic->ic_opmode != IEEE80211_M_AHDEMO)
621 return NULL;
622 /*
623 * Fake up a node; this handles node discovery in
624 * adhoc mode. Note that for the driver's benefit
625 * we we treat this like an association so the driver
626 * has an opportunity to setup it's private state.
627 *
628 * XXX need better way to handle this; issue probe
629 * request so we can deduce rate set, etc.
630 */
631 if ((ni = ieee80211_dup_bss(ic, macaddr)) == NULL)
632 return NULL;
633 /* XXX no rate negotiation; just dup */
634 ni->ni_rates = ic->ic_bss->ni_rates;
635 if (ic->ic_newassoc)
636 (*ic->ic_newassoc)(ic, ni, 1);
637 }
638 return ieee80211_ref_node(ni);
639 }
640
641 /*
642 * It is usually desirable to process a Rx packet using its sender's
643 * node-record instead of the BSS record.
644 *
645 * - AP mode: keep a node-record for every authenticated/associated
646 * station *in the BSS*. For future use, we also track neighboring
647 * APs, since they might belong to the same ESS. APs in the same
648 * ESS may bridge packets to each other, forming a Wireless
649 * Distribution System (WDS).
650 *
651 * - IBSS mode: keep a node-record for every station *in the BSS*.
652 * Also track neighboring stations by their beacons/probe responses.
653 *
654 * - monitor mode: keep a node-record for every sender, regardless
655 * of BSS.
656 *
657 * - STA mode: the only available node-record is the BSS record,
658 * ic->ic_bss.
659 *
660 * Of all the 802.11 Control packets, only the node-records for
661 * RTS packets node-record can be looked up.
662 *
663 * Return non-zero if the packet's node-record is kept, zero
664 * otherwise.
665 */
666 static __inline int
667 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh,
668 u_int8_t **bssid)
669 {
670 struct ieee80211_node *bss = ic->ic_bss;
671 int monitor, rc = 0;
672
673 monitor = (ic->ic_opmode == IEEE80211_M_MONITOR);
674
675 *bssid = NULL;
676
677 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
678 case IEEE80211_FC0_TYPE_CTL:
679 if (!monitor)
680 break;
681 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) ==
682 IEEE80211_FC0_SUBTYPE_RTS;
683 case IEEE80211_FC0_TYPE_MGT:
684 *bssid = wh->i_addr3;
685 switch (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) {
686 case IEEE80211_FC0_SUBTYPE_BEACON:
687 case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
688 rc = 1;
689 break;
690 default:
691 if (ic->ic_opmode == IEEE80211_M_STA)
692 break;
693 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid) ||
694 IEEE80211_ADDR_EQ(*bssid, etherbroadcastaddr);
695 break;
696 }
697 break;
698 case IEEE80211_FC0_TYPE_DATA:
699 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
700 case IEEE80211_FC1_DIR_NODS:
701 *bssid = wh->i_addr3;
702 if (ic->ic_opmode == IEEE80211_M_IBSS ||
703 ic->ic_opmode == IEEE80211_M_AHDEMO)
704 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid);
705 break;
706 case IEEE80211_FC1_DIR_TODS:
707 *bssid = wh->i_addr1;
708 if (ic->ic_opmode == IEEE80211_M_HOSTAP)
709 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid);
710 break;
711 case IEEE80211_FC1_DIR_FROMDS:
712 case IEEE80211_FC1_DIR_DSTODS:
713 *bssid = wh->i_addr2;
714 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP);
715 break;
716 }
717 break;
718 }
719 return monitor || rc;
720 }
721
722 /* Drivers call this, so increase the reference count before returning
723 * the node.
724 */
725 struct ieee80211_node *
726 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh)
727 {
728 struct ieee80211_node *ni;
729 const static u_int8_t zero[IEEE80211_ADDR_LEN];
730 u_int8_t *bssid;
731
732 if (!ieee80211_needs_rxnode(ic, wh, &bssid))
733 return ieee80211_ref_node(ic->ic_bss);
734
735 IEEE80211_NODE_LOCK(ic);
736 ni = _ieee80211_find_node(ic, wh->i_addr2);
737 IEEE80211_NODE_UNLOCK(ic);
738
739 if (ni != NULL)
740 return ieee80211_ref_node(ni);
741
742 if (ic->ic_opmode == IEEE80211_M_HOSTAP)
743 return ieee80211_ref_node(ic->ic_bss);
744
745 /* XXX see remarks in ieee80211_find_txnode */
746 /* XXX no rate negotiation; just dup */
747 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) == NULL)
748 return ieee80211_ref_node(ic->ic_bss);
749
750 IEEE80211_ADDR_COPY(ni->ni_bssid, (bssid != NULL) ? bssid : zero);
751
752 ni->ni_rates = ic->ic_bss->ni_rates;
753 if (ic->ic_newassoc)
754 (*ic->ic_newassoc)(ic, ni, 1);
755
756 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
757 ("%s: faked-up node %p for %s\n", __func__, ni,
758 ether_sprintf(wh->i_addr2)));
759
760 return ieee80211_ref_node(ni);
761 }
762
763 /*
764 * Like find but search based on the channel too.
765 *
766 * Note that ieee80211_find_node_for_beacon does not increase the
767 * reference count before returning the node, because drivers are not
768 * expected to call it.
769 */
770 struct ieee80211_node *
771 ieee80211_find_node_for_beacon(struct ieee80211com *ic, u_int8_t *macaddr,
772 struct ieee80211_channel *chan, char *ssid)
773 {
774 struct ieee80211_node *ni, *best;
775 int hash;
776 int best_score, score;
777
778 best = NULL;
779 best_score = -1;
780
781 hash = IEEE80211_NODE_HASH(macaddr);
782 IEEE80211_NODE_LOCK(ic);
783 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) {
784 if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr))
785 continue;
786
787 score = (ni->ni_chan == chan) ? 1 : 0;
788
789 if (ssid[1] == 0 || ni->ni_esslen == 0)
790 score++;
791 else if (ssid[1] != ni->ni_esslen ||
792 memcmp(ssid + 2, ni->ni_essid, ssid[1]) != 0)
793 continue;
794
795 if (score > best_score) {
796 best = ni;
797 best_score = score;
798 }
799 }
800 IEEE80211_NODE_UNLOCK(ic);
801 return best;
802 }
803
804 static void
805 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni)
806 {
807 IASSERT(ni != ic->ic_bss, ("freeing bss node"));
808
809 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
810 ("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr)));
811 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
812 TAILQ_REMOVE(&ic->ic_node, ni, ni_list);
813 LIST_REMOVE(ni, ni_hash);
814 ic->ic_nnodes--;
815 if (!IF_IS_EMPTY(&ni->ni_savedq)) {
816 IF_PURGE(&ni->ni_savedq);
817 if (ic->ic_set_tim)
818 (*ic->ic_set_tim)(ic, ni->ni_associd, 0);
819 }
820 if (TAILQ_EMPTY(&ic->ic_node))
821 ic->ic_inact_timer = 0;
822 (*ic->ic_node_free)(ic, ni);
823 /* TBD indicate to drivers that a new node can be allocated */
824 }
825
826 void
827 ieee80211_release_node(struct ieee80211com *ic, struct ieee80211_node *ni)
828 {
829 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
830 ("%s %s refcnt %d\n", __func__,
831 ether_sprintf(ni->ni_macaddr), ni->ni_refcnt));
832 if (ieee80211_node_decref(ni) == 0 &&
833 ni->ni_state == IEEE80211_STA_COLLECT) {
834 IEEE80211_NODE_LOCK_BH(ic);
835 ieee80211_free_node(ic, ni);
836 IEEE80211_NODE_UNLOCK_BH(ic);
837 }
838 }
839
840 void
841 ieee80211_free_allnodes(struct ieee80211com *ic)
842 {
843 struct ieee80211_node *ni;
844
845 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, ("free all nodes\n"));
846 IEEE80211_NODE_LOCK_BH(ic);
847 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL)
848 ieee80211_free_node(ic, ni);
849 IEEE80211_NODE_UNLOCK_BH(ic);
850
851 if (ic->ic_bss != NULL)
852 node_cleanup(ic, ic->ic_bss); /* for station mode */
853 }
854
855 /*
856 * Timeout inactive nodes. Note that we cannot hold the node
857 * lock while sending a frame as this would lead to a LOR.
858 * Instead we use a generation number to mark nodes that we've
859 * scanned and drop the lock and restart a scan if we have to
860 * time out a node. Since we are single-threaded by virtue of
861 * controlling the inactivity timer we can be sure this will
862 * process each node only once.
863 */
864 void
865 ieee80211_clean_nodes(struct ieee80211com *ic)
866 {
867 struct ieee80211_node *ni;
868 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/
869
870 restart:
871 IEEE80211_NODE_LOCK(ic);
872 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
873 if (ic->ic_nnodes <= ic->ic_max_nnodes)
874 break;
875 if (ni->ni_scangen == gen) /* previously handled */
876 continue;
877 ni->ni_scangen = gen;
878 if (ni->ni_refcnt > 0)
879 continue;
880 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
881 ("station %s purged from LRU cache\n",
882 ether_sprintf(ni->ni_macaddr)));
883 /*
884 * Send a deauthenticate frame.
885 *
886 * Drop the node lock before sending the
887 * deauthentication frame in case the driver takes
888 * a lock, as this will result in a LOR between the
889 * node lock and the driver lock.
890 */
891 IEEE80211_NODE_UNLOCK(ic);
892 if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
893 IEEE80211_SEND_MGMT(ic, ni,
894 IEEE80211_FC0_SUBTYPE_DEAUTH,
895 IEEE80211_REASON_AUTH_EXPIRE);
896 ieee80211_node_leave(ic, ni);
897 } else
898 ieee80211_free_node(ic, ni);
899 ic->ic_stats.is_node_timeout++;
900 goto restart;
901 }
902 IEEE80211_NODE_UNLOCK(ic);
903 }
904
905 void
906 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg)
907 {
908 struct ieee80211_node *ni;
909
910 IEEE80211_NODE_LOCK(ic);
911 TAILQ_FOREACH(ni, &ic->ic_node, ni_list)
912 (*f)(arg, ni);
913 IEEE80211_NODE_UNLOCK(ic);
914 }
915
916 void
917 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
918 {
919 int newassoc;
920
921 if (ni->ni_associd == 0) {
922 u_int16_t aid;
923
924 /*
925 * It would be clever to search the bitmap
926 * more efficiently, but this will do for now.
927 */
928 for (aid = 1; aid < ic->ic_max_aid; aid++) {
929 if (!IEEE80211_AID_ISSET(aid,
930 ic->ic_aid_bitmap))
931 break;
932 }
933 if (aid >= ic->ic_max_aid) {
934 IEEE80211_SEND_MGMT(ic, ni, resp,
935 IEEE80211_REASON_ASSOC_TOOMANY);
936 ieee80211_node_leave(ic, ni);
937 return;
938 }
939 ni->ni_associd = aid | 0xc000;
940 IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
941 newassoc = 1;
942 /* XXX for 11g must turn off short slot time if long
943 slot time sta associates */
944 } else
945 newassoc = 0;
946
947 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
948 ("station %s %s associated at aid %d\n",
949 ether_sprintf(ni->ni_macaddr),
950 (newassoc ? "newly" : "already"),
951 ni->ni_associd & ~0xc000));
952
953 /* give driver a chance to setup state like ni_txrate */
954 if (ic->ic_newassoc)
955 (*ic->ic_newassoc)(ic, ni, newassoc);
956 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
957 ieee80211_node_newstate(ni, IEEE80211_STA_ASSOC);
958 }
959
960 /*
961 * Handle bookkeeping for station deauthentication/disassociation
962 * when operating as an ap.
963 */
964 void
965 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
966 {
967
968 IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP,
969 ("not in ap mode, mode %u", ic->ic_opmode));
970 /*
971 * If node wasn't previously associated all
972 * we need to do is reclaim the reference.
973 */
974 if (ni->ni_associd == 0)
975 return;
976 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
977 ni->ni_associd = 0;
978 ieee80211_node_newstate(ni, IEEE80211_STA_COLLECT);
979 }
Cache object: 29b3857958366eb618616a07d0c34c5b
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