ieee80211_node.c revision 1.11
1 /* $NetBSD: ieee80211_node.c,v 1.11 2004/04/30 23:58:14 dyoung 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 1.22 2004/04/05 04:15:55 sam Exp $"); 37 #else 38 __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.11 2004/04/30 23:58:14 dyoung 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 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 struct ieee80211_node *ni; 123 124 ni = (*ic->ic_node_alloc)(ic); 125 IASSERT(ni != NULL, ("unable to setup inital BSS node")); 126 ni->ni_chan = IEEE80211_CHAN_ANYC; 127 ic->ic_bss = ni; 128 ic->ic_txpower = IEEE80211_TXPOWER_MAX; 129 } 130 131 void 132 ieee80211_node_detach(struct ifnet *ifp) 133 { 134 struct ieee80211com *ic = (void *)ifp; 135 136 if (ic->ic_bss != NULL) 137 (*ic->ic_node_free)(ic, ic->ic_bss); 138 ieee80211_free_allnodes(ic); 139 #ifdef __FreeBSD__ 140 IEEE80211_NODE_LOCK_DESTROY(ic); 141 #endif 142 } 143 144 /* 145 * AP scanning support. 146 */ 147 148 /* 149 * Initialize the active channel set based on the set 150 * of available channels and the current PHY mode. 151 */ 152 static void 153 ieee80211_reset_scan(struct ifnet *ifp) 154 { 155 struct ieee80211com *ic = (void *)ifp; 156 157 memcpy(ic->ic_chan_scan, ic->ic_chan_active, 158 sizeof(ic->ic_chan_active)); 159 /* NB: hack, setup so next_scan starts with the first channel */ 160 if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC) 161 ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX]; 162 } 163 164 /* 165 * Begin an active scan. 166 */ 167 void 168 ieee80211_begin_scan(struct ifnet *ifp) 169 { 170 struct ieee80211com *ic = (void *)ifp; 171 172 /* 173 * In all but hostap mode scanning starts off in 174 * an active mode before switching to passive. 175 */ 176 if (ic->ic_opmode != IEEE80211_M_HOSTAP) { 177 ic->ic_flags |= IEEE80211_F_ASCAN; 178 ic->ic_stats.is_scan_active++; 179 } else 180 ic->ic_stats.is_scan_passive++; 181 if (ifp->if_flags & IFF_DEBUG) 182 if_printf(ifp, "begin %s scan\n", 183 (ic->ic_flags & IEEE80211_F_ASCAN) ? 184 "active" : "passive"); 185 /* 186 * Clear scan state and flush any previously seen 187 * AP's. Note that the latter assumes we don't act 188 * as both an AP and a station, otherwise we'll 189 * potentially flush state of stations associated 190 * with us. 191 */ 192 ieee80211_reset_scan(ifp); 193 ieee80211_free_allnodes(ic); 194 195 /* Scan the next channel. */ 196 ieee80211_next_scan(ifp); 197 } 198 199 /* 200 * Switch to the next channel marked for scanning. 201 */ 202 void 203 ieee80211_next_scan(struct ifnet *ifp) 204 { 205 struct ieee80211com *ic = (void *)ifp; 206 struct ieee80211_channel *chan; 207 208 chan = ic->ic_bss->ni_chan; 209 for (;;) { 210 if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX]) 211 chan = &ic->ic_channels[0]; 212 if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) { 213 /* 214 * Honor channels marked passive-only 215 * during an active scan. 216 */ 217 if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 || 218 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) 219 break; 220 } 221 if (chan == ic->ic_bss->ni_chan) { 222 ieee80211_end_scan(ifp); 223 return; 224 } 225 } 226 clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan)); 227 IEEE80211_DPRINTF(("ieee80211_next_scan: chan %d->%d\n", 228 ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan), 229 ieee80211_chan2ieee(ic, chan))); 230 ic->ic_bss->ni_chan = chan; 231 ieee80211_new_state(ic, IEEE80211_S_SCAN, -1); 232 } 233 234 void 235 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan) 236 { 237 struct ieee80211_node *ni; 238 struct ifnet *ifp = &ic->ic_if; 239 240 ni = ic->ic_bss; 241 if (ifp->if_flags & IFF_DEBUG) 242 if_printf(ifp, "creating ibss\n"); 243 ic->ic_flags |= IEEE80211_F_SIBSS; 244 ni->ni_chan = chan; 245 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)]; 246 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr); 247 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr); 248 if (ic->ic_opmode == IEEE80211_M_IBSS) 249 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */ 250 ni->ni_esslen = ic->ic_des_esslen; 251 memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen); 252 ni->ni_rssi = 0; 253 ni->ni_rstamp = 0; 254 memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp)); 255 ni->ni_intval = ic->ic_lintval; 256 ni->ni_capinfo = IEEE80211_CAPINFO_IBSS; 257 if (ic->ic_flags & IEEE80211_F_WEPON) 258 ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY; 259 if (ic->ic_phytype == IEEE80211_T_FH) { 260 ni->ni_fhdwell = 200; /* XXX */ 261 ni->ni_fhindex = 1; 262 } 263 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 264 } 265 266 int 267 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni) 268 { 269 struct ifnet *ifp = &ic->ic_if; 270 u_int8_t rate; 271 int fail; 272 273 fail = 0; 274 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan))) 275 fail |= 0x01; 276 if (ic->ic_des_chan != IEEE80211_CHAN_ANYC && 277 ni->ni_chan != ic->ic_des_chan) 278 fail |= 0x01; 279 if (ic->ic_opmode == IEEE80211_M_IBSS) { 280 if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 281 fail |= 0x02; 282 } else { 283 if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0) 284 fail |= 0x02; 285 } 286 if (ic->ic_flags & IEEE80211_F_WEPON) { 287 if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 288 fail |= 0x04; 289 } else { 290 /* XXX does this mean privacy is supported or required? */ 291 if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) 292 fail |= 0x04; 293 } 294 rate = ieee80211_fix_rate(ic, ni, IEEE80211_F_DONEGO); 295 if (rate & IEEE80211_RATE_BASIC) 296 fail |= 0x08; 297 if (ic->ic_des_esslen != 0 && 298 (ni->ni_esslen != ic->ic_des_esslen || 299 memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0)) 300 fail |= 0x10; 301 if ((ic->ic_flags & IEEE80211_F_DESBSSID) && 302 !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid)) 303 fail |= 0x20; 304 #ifdef IEEE80211_DEBUG 305 if (ifp->if_flags & IFF_DEBUG) { 306 printf(" %c %s", fail ? '-' : '+', 307 ether_sprintf(ni->ni_macaddr)); 308 printf(" %s%c", ether_sprintf(ni->ni_bssid), 309 fail & 0x20 ? '!' : ' '); 310 printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan), 311 fail & 0x01 ? '!' : ' '); 312 printf(" %+4d", ni->ni_rssi); 313 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 314 fail & 0x08 ? '!' : ' '); 315 printf(" %4s%c", 316 (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 317 (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : 318 "????", 319 fail & 0x02 ? '!' : ' '); 320 printf(" %3s%c ", 321 (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 322 "wep" : "no", 323 fail & 0x04 ? '!' : ' '); 324 ieee80211_print_essid(ni->ni_essid, ni->ni_esslen); 325 printf("%s\n", fail & 0x10 ? "!" : ""); 326 } 327 #endif 328 return fail; 329 } 330 331 /* 332 * Complete a scan of potential channels. 333 */ 334 void 335 ieee80211_end_scan(struct ifnet *ifp) 336 { 337 struct ieee80211com *ic = (void *)ifp; 338 struct ieee80211_node *ni, *nextbs, *selbs; 339 int i, fail; 340 341 ic->ic_flags &= ~IEEE80211_F_ASCAN; 342 ni = TAILQ_FIRST(&ic->ic_node); 343 344 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 345 /* XXX off stack? */ 346 u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)]; 347 /* 348 * The passive scan to look for existing AP's completed, 349 * select a channel to camp on. Identify the channels 350 * that already have one or more AP's and try to locate 351 * an unnoccupied one. If that fails, pick a random 352 * channel from the active set. 353 */ 354 for (; ni != NULL; ni = nextbs) { 355 ieee80211_ref_node(ni); 356 nextbs = TAILQ_NEXT(ni, ni_list); 357 setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan)); 358 ieee80211_free_node(ic, ni); 359 } 360 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 361 if (isset(ic->ic_chan_active, i) && isclr(occupied, i)) 362 break; 363 if (i == IEEE80211_CHAN_MAX) { 364 fail = arc4random() & 3; /* random 0-3 */ 365 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 366 if (isset(ic->ic_chan_active, i) && fail-- == 0) 367 break; 368 } 369 ieee80211_create_ibss(ic, &ic->ic_channels[i]); 370 return; 371 } 372 if (ni == NULL) { 373 IEEE80211_DPRINTF(("%s: no scan candidate\n", __func__)); 374 notfound: 375 if (ic->ic_opmode == IEEE80211_M_IBSS && 376 (ic->ic_flags & IEEE80211_F_IBSSON) && 377 ic->ic_des_esslen != 0) { 378 ieee80211_create_ibss(ic, ic->ic_ibss_chan); 379 return; 380 } 381 /* 382 * Reset the list of channels to scan and start again. 383 */ 384 ieee80211_reset_scan(ifp); 385 ieee80211_next_scan(ifp); 386 return; 387 } 388 selbs = NULL; 389 if (ifp->if_flags & IFF_DEBUG) 390 if_printf(ifp, "\tmacaddr bssid chan rssi rate flag wep essid\n"); 391 for (; ni != NULL; ni = nextbs) { 392 ieee80211_ref_node(ni); 393 nextbs = TAILQ_NEXT(ni, ni_list); 394 if (ni->ni_fails) { 395 /* 396 * The configuration of the access points may change 397 * during my scan. So delete the entry for the AP 398 * and retry to associate if there is another beacon. 399 */ 400 if (ni->ni_fails++ > 2) 401 ieee80211_free_node(ic, ni); 402 continue; 403 } 404 if (ieee80211_match_bss(ic, ni) == 0) { 405 if (selbs == NULL) 406 selbs = ni; 407 else if (ni->ni_rssi > selbs->ni_rssi) { 408 ieee80211_unref_node(&selbs); 409 selbs = ni; 410 } else 411 ieee80211_unref_node(&ni); 412 } else { 413 ieee80211_unref_node(&ni); 414 } 415 } 416 if (selbs == NULL) 417 goto notfound; 418 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs); 419 if (ic->ic_opmode == IEEE80211_M_IBSS) { 420 ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE | 421 IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 422 if (ic->ic_bss->ni_rates.rs_nrates == 0) { 423 selbs->ni_fails++; 424 ieee80211_unref_node(&selbs); 425 goto notfound; 426 } 427 ieee80211_unref_node(&selbs); 428 /* 429 * Discard scan set; the nodes have a refcnt of zero 430 * and have not asked the driver to setup private 431 * node state. Let them be repopulated on demand either 432 * through transmission (ieee80211_find_txnode) or receipt 433 * of a probe response (to be added). 434 */ 435 ieee80211_free_allnodes(ic); 436 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 437 } else { 438 ieee80211_unref_node(&selbs); 439 ieee80211_new_state(ic, IEEE80211_S_AUTH, -1); 440 } 441 } 442 443 int 444 ieee80211_get_rate(struct ieee80211com *ic) 445 { 446 u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE]; 447 int rate; 448 449 rates = &ic->ic_bss->ni_rates.rs_rates; 450 451 if (ic->ic_fixed_rate != -1) 452 rate = (*rates)[ic->ic_fixed_rate]; 453 else if (ic->ic_state == IEEE80211_S_RUN) 454 rate = (*rates)[ic->ic_bss->ni_txrate]; 455 else 456 rate = 0; 457 458 return rate & IEEE80211_RATE_VAL; 459 } 460 461 static struct ieee80211_node * 462 ieee80211_node_alloc(struct ieee80211com *ic) 463 { 464 struct ieee80211_node *ni; 465 MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node), 466 M_80211_NODE, M_NOWAIT | M_ZERO); 467 return ni; 468 } 469 470 static void 471 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni) 472 { 473 if (ni->ni_challenge != NULL) { 474 FREE(ni->ni_challenge, M_DEVBUF); 475 ni->ni_challenge = NULL; 476 } 477 FREE(ni, M_80211_NODE); 478 } 479 480 static void 481 ieee80211_node_copy(struct ieee80211com *ic, 482 struct ieee80211_node *dst, const struct ieee80211_node *src) 483 { 484 *dst = *src; 485 dst->ni_challenge = NULL; 486 } 487 488 static u_int8_t 489 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni) 490 { 491 return ni->ni_rssi; 492 } 493 494 static void 495 ieee80211_setup_node(struct ieee80211com *ic, 496 struct ieee80211_node *ni, u_int8_t *macaddr) 497 { 498 int hash; 499 ieee80211_node_critsec_decl(s); 500 501 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr); 502 hash = IEEE80211_NODE_HASH(macaddr); 503 ni->ni_refcnt = 1; /* mark referenced */ 504 ieee80211_node_critsec_begin(ic, s); 505 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 506 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); 507 /* 508 * Note we don't enable the inactive timer when acting 509 * as a station. Nodes created in this mode represent 510 * AP's identified while scanning. If we time them out 511 * then several things happen: we can't return the data 512 * to users to show the list of AP's we encountered, and 513 * more importantly, we'll incorrectly deauthenticate 514 * ourself because the inactivity timer will kick us off. 515 */ 516 if (ic->ic_opmode != IEEE80211_M_STA) 517 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 518 ieee80211_node_critsec_end(ic, s); 519 } 520 521 struct ieee80211_node * 522 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) 523 { 524 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 525 if (ni != NULL) 526 ieee80211_setup_node(ic, ni, macaddr); 527 else 528 ic->ic_stats.is_rx_nodealloc++; 529 return ni; 530 } 531 532 struct ieee80211_node * 533 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) 534 { 535 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 536 if (ni != NULL) { 537 ieee80211_setup_node(ic, ni, macaddr); 538 /* 539 * Inherit from ic_bss. 540 */ 541 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 542 ni->ni_chan = ic->ic_bss->ni_chan; 543 } else 544 ic->ic_stats.is_rx_nodealloc++; 545 return ni; 546 } 547 548 static struct ieee80211_node * 549 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 550 { 551 struct ieee80211_node *ni; 552 int hash; 553 554 #ifdef __FreeBSD__ 555 IEEE80211_NODE_LOCK_ASSERT(ic); 556 #endif /* __FreeBSD__ */ 557 558 hash = IEEE80211_NODE_HASH(macaddr); 559 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 560 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { 561 ieee80211_node_incref(ni); /* mark referenced */ 562 return ni; 563 } 564 } 565 return NULL; 566 } 567 568 struct ieee80211_node * 569 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 570 { 571 struct ieee80211_node *ni; 572 ieee80211_node_critsec_decl(s); 573 574 ieee80211_node_critsec_begin(ic, s); 575 ni = _ieee80211_find_node(ic, macaddr); 576 ieee80211_node_critsec_end(ic, s); 577 return ni; 578 } 579 580 /* 581 * Return a reference to the appropriate node for sending 582 * a data frame. This handles node discovery in adhoc networks. 583 */ 584 struct ieee80211_node * 585 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr) 586 { 587 struct ieee80211_node *ni; 588 ieee80211_node_critsec_decl(s); 589 590 /* 591 * The destination address should be in the node table 592 * unless we are operating in station mode or this is a 593 * multicast/broadcast frame. 594 */ 595 if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr)) 596 return ic->ic_bss; 597 598 /* XXX can't hold lock across dup_bss 'cuz of recursive locking */ 599 ieee80211_node_critsec_begin(ic, s); 600 ni = _ieee80211_find_node(ic, macaddr); 601 ieee80211_node_critsec_end(ic, s); 602 if (ni == NULL && 603 (ic->ic_opmode == IEEE80211_M_IBSS || 604 ic->ic_opmode == IEEE80211_M_AHDEMO)) { 605 /* 606 * Fake up a node; this handles node discovery in 607 * adhoc mode. Note that for the driver's benefit 608 * we we treat this like an association so the driver 609 * has an opportunity to setup it's private state. 610 * 611 * XXX need better way to handle this; issue probe 612 * request so we can deduce rate set, etc. 613 */ 614 ni = ieee80211_dup_bss(ic, macaddr); 615 if (ni != NULL) { 616 /* XXX no rate negotiation; just dup */ 617 ni->ni_rates = ic->ic_bss->ni_rates; 618 if (ic->ic_newassoc) 619 (*ic->ic_newassoc)(ic, ni, 1); 620 } 621 } 622 return ni; 623 } 624 625 /* 626 * For some types of packet and for some operating modes, it is 627 * desirable to process a Rx packet using its sender's node-record 628 * instead of the BSS record, when that is possible. 629 * 630 * - AP mode: it is desirable to keep a node-record for every 631 * authenticated/associated station *in the BSS*. For future use, 632 * we also track neighboring APs, since they might belong to the 633 * same ESSID. 634 * 635 * - IBSS mode: it is desirable to keep a node-record for every 636 * station *in the BSS*. 637 * 638 * - monitor mode: it is desirable to keep a node-record for every 639 * sender, regardless of BSS. 640 * 641 * - STA mode: the only available node-record is the BSS record, 642 * ic->ic_bss. 643 * 644 * Of all the 802.11 Control packets, only the node-records for 645 * RTS packets node-record can be looked up. 646 * 647 * Return non-zero if the packet's node-record is kept, zero 648 * otherwise. 649 */ 650 static __inline int 651 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh, 652 u_int8_t **bssid) 653 { 654 struct ieee80211_node *bss = ic->ic_bss; 655 int needsnode, rc = 0; 656 657 if (ic->ic_opmode == IEEE80211_M_STA) 658 return 0; 659 660 needsnode = (ic->ic_opmode == IEEE80211_M_MONITOR); 661 662 *bssid = NULL; 663 664 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) { 665 case IEEE80211_FC0_TYPE_CTL: 666 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == 667 IEEE80211_FC0_SUBTYPE_RTS; 668 669 case IEEE80211_FC0_TYPE_MGT: 670 *bssid = wh->i_addr3; 671 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 672 break; 673 case IEEE80211_FC0_TYPE_DATA: 674 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { 675 case IEEE80211_FC1_DIR_NODS: 676 *bssid = wh->i_addr3; 677 if (ic->ic_opmode == IEEE80211_M_IBSS || 678 ic->ic_opmode == IEEE80211_M_AHDEMO) 679 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 680 break; 681 case IEEE80211_FC1_DIR_TODS: 682 *bssid = wh->i_addr1; 683 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 684 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 685 break; 686 case IEEE80211_FC1_DIR_FROMDS: 687 case IEEE80211_FC1_DIR_DSTODS: 688 *bssid = wh->i_addr2; 689 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); 690 break; 691 } 692 break; 693 } 694 return needsnode || rc; 695 } 696 697 struct ieee80211_node * 698 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) 699 { 700 struct ieee80211_node *ni; 701 const static u_int8_t zero[IEEE80211_ADDR_LEN]; 702 u_int8_t *bssid; 703 ieee80211_node_critsec_decl(s); 704 705 if (!ieee80211_needs_rxnode(ic, wh, &bssid)) 706 return ieee80211_ref_node(ic->ic_bss); 707 708 ieee80211_node_critsec_begin(ic, s); 709 ni = _ieee80211_find_node(ic, wh->i_addr2); 710 ieee80211_node_critsec_end(ic, s); 711 712 if (ni == NULL) { 713 if (ic->ic_opmode != IEEE80211_M_HOSTAP) { 714 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) != NULL) 715 IEEE80211_ADDR_COPY(ni->ni_bssid, 716 (bssid != NULL) ? bssid : zero); 717 718 IEEE80211_DPRINTF(("%s: faked-up node %p for %s\n", 719 __func__, ni, ether_sprintf(wh->i_addr2))); 720 } 721 ni = ieee80211_ref_node((ni == NULL) ? ic->ic_bss : ni); 722 } 723 IASSERT(ni != NULL, ("%s: null node", __func__)); 724 return ni; 725 } 726 727 /* 728 * Like find but search based on the channel too. 729 */ 730 struct ieee80211_node * 731 ieee80211_lookup_node(struct ieee80211com *ic, 732 u_int8_t *macaddr, struct ieee80211_channel *chan) 733 { 734 struct ieee80211_node *ni; 735 int hash; 736 ieee80211_node_critsec_decl(s); 737 738 hash = IEEE80211_NODE_HASH(macaddr); 739 ieee80211_node_critsec_begin(ic, s); 740 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 741 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) && 742 ni->ni_chan == chan) { 743 ieee80211_node_incref(ni);/* mark referenced */ 744 break; 745 } 746 } 747 ieee80211_node_critsec_end(ic, s); 748 return ni; 749 } 750 751 static void 752 _ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 753 { 754 IASSERT(ni != ic->ic_bss, ("freeing bss node")); 755 756 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 757 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 758 LIST_REMOVE(ni, ni_hash); 759 if (!IF_IS_EMPTY(&ni->ni_savedq)) { 760 IF_PURGE(&ni->ni_savedq); 761 if (ic->ic_set_tim) 762 ic->ic_set_tim(ic, ni->ni_associd, 0); 763 } 764 if (TAILQ_EMPTY(&ic->ic_node)) 765 ic->ic_inact_timer = 0; 766 (*ic->ic_node_free)(ic, ni); 767 } 768 769 void 770 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 771 { 772 ieee80211_node_critsec_decl(s); 773 774 IASSERT(ni != ic->ic_bss, ("freeing ic_bss")); 775 776 if (ieee80211_node_decref(ni) == 0) { 777 ieee80211_node_critsec_begin(ic, s); 778 _ieee80211_free_node(ic, ni); 779 ieee80211_node_critsec_end(ic, s); 780 } 781 } 782 783 void 784 ieee80211_free_allnodes(struct ieee80211com *ic) 785 { 786 struct ieee80211_node *ni; 787 ieee80211_node_critsec_decl(s); 788 789 ieee80211_node_critsec_begin(ic, s); 790 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) 791 _ieee80211_free_node(ic, ni); 792 ieee80211_node_critsec_end(ic, s); 793 } 794 795 /* 796 * Timeout inactive nodes. Note that we cannot hold the node 797 * lock while sending a frame as this would lead to a LOR. 798 * Instead we use a generation number to mark nodes that we've 799 * scanned and drop the lock and restart a scan if we have to 800 * time out a node. Since we are single-threaded by virtue of 801 * controlling the inactivity timer we can be sure this will 802 * process each node only once. 803 */ 804 void 805 ieee80211_timeout_nodes(struct ieee80211com *ic) 806 { 807 struct ieee80211_node *ni; 808 ieee80211_node_critsec_decl(s); 809 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ 810 811 restart: 812 ieee80211_node_critsec_begin(ic, s); 813 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) { 814 if (ni->ni_scangen == gen) /* previously handled */ 815 continue; 816 ni->ni_scangen = gen; 817 if (++ni->ni_inact > IEEE80211_INACT_MAX) { 818 IEEE80211_DPRINTF(("station %s timed out " 819 "due to inactivity (%u secs)\n", 820 ether_sprintf(ni->ni_macaddr), 821 ni->ni_inact)); 822 /* 823 * Send a deauthenticate frame. 824 * 825 * Drop the node lock before sending the 826 * deauthentication frame in case the driver takes 827 * a lock, as this will result in a LOR between the 828 * node lock and the driver lock. 829 */ 830 ieee80211_node_critsec_end(ic, s); 831 IEEE80211_SEND_MGMT(ic, ni, 832 IEEE80211_FC0_SUBTYPE_DEAUTH, 833 IEEE80211_REASON_AUTH_EXPIRE); 834 ieee80211_free_node(ic, ni); 835 ic->ic_stats.is_node_timeout++; 836 goto restart; 837 } 838 } 839 if (!TAILQ_EMPTY(&ic->ic_node)) 840 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 841 ieee80211_node_critsec_end(ic, s); 842 } 843 844 void 845 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) 846 { 847 struct ieee80211_node *ni; 848 ieee80211_node_critsec_decl(s); 849 850 ieee80211_node_critsec_begin(ic, s); 851 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) 852 (*f)(arg, ni); 853 ieee80211_node_critsec_end(ic, s); 854 } 855
Indexes created Tue Sep 23 14:10:03 GMT 2025