ieee80211_node.c revision 1.33
1 /* $NetBSD: ieee80211_node.c,v 1.33 2004/08/10 00:57:21 dyoung 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 1.33 2004/08/10 00:57:21 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 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 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("creating ibss\n")); 262 ic->ic_flags |= IEEE80211_F_SIBSS; 263 ni->ni_chan = chan; 264 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)]; 265 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr); 266 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr); 267 if (ic->ic_opmode == IEEE80211_M_IBSS) { 268 if ((ic->ic_flags & IEEE80211_F_DESBSSID) != 0) 269 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid); 270 else 271 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */ 272 } 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 ieee80211_node_newstate(selbs, IEEE80211_STA_BSS); 436 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs); 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 { 478 479 if (ni->ni_challenge != NULL) { 480 FREE(ni->ni_challenge, M_DEVBUF); 481 ni->ni_challenge = NULL; 482 } 483 } 484 485 static void 486 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni) 487 { 488 node_cleanup(ic, ni); 489 FREE(ni, M_80211_NODE); 490 } 491 492 static void 493 ieee80211_node_copy(struct ieee80211com *ic, 494 struct ieee80211_node *dst, const struct ieee80211_node *src) 495 { 496 node_cleanup(ic, dst); 497 *dst = *src; 498 dst->ni_challenge = NULL; 499 } 500 501 static u_int8_t 502 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni) 503 { 504 return ni->ni_rssi; 505 } 506 507 static void 508 ieee80211_setup_node(struct ieee80211com *ic, 509 struct ieee80211_node *ni, u_int8_t *macaddr) 510 { 511 int hash; 512 513 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 514 ("%s %s\n", __func__, ether_sprintf(macaddr))); 515 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr); 516 hash = IEEE80211_NODE_HASH(macaddr); 517 ieee80211_node_newstate(ni, IEEE80211_STA_CACHE); 518 519 IEEE80211_NODE_LOCK_BH(ic); 520 /* 521 * Note we don't enable the inactive timer when acting 522 * as a station. Nodes created in this mode represent 523 * AP's identified while scanning. If we time them out 524 * then several things happen: we can't return the data 525 * to users to show the list of AP's we encountered, and 526 * more importantly, we'll incorrectly deauthenticate 527 * ourself because the inactivity timer will kick us off. 528 */ 529 if (ic->ic_opmode != IEEE80211_M_STA && 530 TAILQ_EMPTY(&ic->ic_node)) 531 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 532 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 533 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); 534 IEEE80211_NODE_UNLOCK_BH(ic); 535 } 536 537 struct ieee80211_node * 538 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) 539 { 540 struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic); 541 if (ni != NULL) { 542 ieee80211_setup_node(ic, ni, macaddr); 543 } else 544 ic->ic_stats.is_rx_nodealloc++; 545 return ni; 546 } 547 548 struct ieee80211_node * 549 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) 550 { 551 struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic); 552 if (ni != NULL) { 553 ieee80211_setup_node(ic, ni, macaddr); 554 /* 555 * Inherit from ic_bss. 556 */ 557 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 558 ni->ni_chan = ic->ic_bss->ni_chan; 559 } else 560 ic->ic_stats.is_rx_nodealloc++; 561 return ni; 562 } 563 564 static struct ieee80211_node * 565 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 566 { 567 struct ieee80211_node *ni; 568 int hash; 569 570 IEEE80211_NODE_LOCK_ASSERT(ic); 571 572 hash = IEEE80211_NODE_HASH(macaddr); 573 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 574 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { 575 /* least-recently used is at tail */ 576 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 577 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 578 return ni; 579 } 580 } 581 return NULL; 582 } 583 584 struct ieee80211_node * 585 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 586 { 587 struct ieee80211_node *ni; 588 589 IEEE80211_NODE_LOCK(ic); 590 ni = _ieee80211_find_node(ic, macaddr); 591 IEEE80211_NODE_UNLOCK(ic); 592 return ni; 593 } 594 595 /* 596 * Return a reference to the appropriate node for sending 597 * a data frame. This handles node discovery in adhoc networks. 598 * 599 * Drivers will call this, so increase the reference count before 600 * returning the node. 601 */ 602 struct ieee80211_node * 603 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr) 604 { 605 struct ieee80211_node *ni; 606 607 /* 608 * The destination address should be in the node table 609 * unless we are operating in station mode or this is a 610 * multicast/broadcast frame. 611 */ 612 if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr)) 613 return ieee80211_ref_node(ic->ic_bss); 614 615 /* XXX can't hold lock across dup_bss 'cuz of recursive locking */ 616 IEEE80211_NODE_LOCK(ic); 617 ni = _ieee80211_find_node(ic, macaddr); 618 IEEE80211_NODE_UNLOCK(ic); 619 if (ni == NULL && 620 (ic->ic_opmode == IEEE80211_M_IBSS || 621 ic->ic_opmode == IEEE80211_M_AHDEMO)) { 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 ni = ieee80211_dup_bss(ic, macaddr); 632 if (ni != 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 } 639 return ieee80211_ref_node(ni); 640 } 641 642 /* 643 * It is usually desirable to process a Rx packet using its sender's 644 * node-record instead of the BSS record. 645 * 646 * - AP mode: keep a node-record for every authenticated/associated 647 * station *in the BSS*. For future use, we also track neighboring 648 * APs, since they might belong to the same ESS. APs in the same 649 * ESS may bridge packets to each other, forming a Wireless 650 * Distribution System (WDS). 651 * 652 * - IBSS mode: keep a node-record for every station *in the BSS*. 653 * Also track neighboring stations by their beacons/probe responses. 654 * 655 * - monitor mode: keep a node-record for every sender, regardless 656 * of BSS. 657 * 658 * - STA mode: the only available node-record is the BSS record, 659 * ic->ic_bss. 660 * 661 * Of all the 802.11 Control packets, only the node-records for 662 * RTS packets node-record can be looked up. 663 * 664 * Return non-zero if the packet's node-record is kept, zero 665 * otherwise. 666 */ 667 static __inline int 668 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh, 669 u_int8_t **bssid) 670 { 671 struct ieee80211_node *bss = ic->ic_bss; 672 int monitor, rc = 0; 673 674 monitor = (ic->ic_opmode == IEEE80211_M_MONITOR); 675 676 *bssid = NULL; 677 678 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) { 679 case IEEE80211_FC0_TYPE_CTL: 680 if (!monitor) 681 break; 682 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == 683 IEEE80211_FC0_SUBTYPE_RTS; 684 case IEEE80211_FC0_TYPE_MGT: 685 *bssid = wh->i_addr3; 686 switch (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) { 687 case IEEE80211_FC0_SUBTYPE_BEACON: 688 case IEEE80211_FC0_SUBTYPE_PROBE_RESP: 689 rc = 1; 690 break; 691 default: 692 if (ic->ic_opmode == IEEE80211_M_STA) 693 break; 694 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid) || 695 IEEE80211_ADDR_EQ(*bssid, etherbroadcastaddr); 696 break; 697 } 698 break; 699 case IEEE80211_FC0_TYPE_DATA: 700 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { 701 case IEEE80211_FC1_DIR_NODS: 702 *bssid = wh->i_addr3; 703 if (ic->ic_opmode == IEEE80211_M_IBSS || 704 ic->ic_opmode == IEEE80211_M_AHDEMO) 705 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 706 break; 707 case IEEE80211_FC1_DIR_TODS: 708 *bssid = wh->i_addr1; 709 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 710 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 711 break; 712 case IEEE80211_FC1_DIR_FROMDS: 713 case IEEE80211_FC1_DIR_DSTODS: 714 *bssid = wh->i_addr2; 715 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); 716 break; 717 } 718 break; 719 } 720 return monitor || rc; 721 } 722 723 /* Drivers call this, so increase the reference count before returning 724 * the node. 725 */ 726 struct ieee80211_node * 727 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) 728 { 729 struct ieee80211_node *ni; 730 const static u_int8_t zero[IEEE80211_ADDR_LEN]; 731 u_int8_t *bssid; 732 733 if (!ieee80211_needs_rxnode(ic, wh, &bssid)) 734 return ieee80211_ref_node(ic->ic_bss); 735 736 IEEE80211_NODE_LOCK(ic); 737 ni = _ieee80211_find_node(ic, wh->i_addr2); 738 IEEE80211_NODE_UNLOCK(ic); 739 740 if (ni != NULL) 741 return ieee80211_ref_node(ni); 742 743 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 744 return ieee80211_ref_node(ic->ic_bss); 745 746 /* XXX see remarks in ieee80211_find_txnode */ 747 /* XXX no rate negotiation; just dup */ 748 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) == NULL) 749 return ieee80211_ref_node(ic->ic_bss); 750 751 IEEE80211_ADDR_COPY(ni->ni_bssid, (bssid != NULL) ? bssid : zero); 752 753 ni->ni_rates = ic->ic_bss->ni_rates; 754 if (ic->ic_newassoc) 755 (*ic->ic_newassoc)(ic, ni, 1); 756 757 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 758 ("%s: faked-up node %p for %s\n", __func__, ni, 759 ether_sprintf(wh->i_addr2))); 760 761 return ieee80211_ref_node(ni); 762 } 763 764 /* 765 * Like find but search based on the channel too. 766 */ 767 struct ieee80211_node * 768 ieee80211_find_node_for_beacon(struct ieee80211com *ic, u_int8_t *macaddr, 769 struct ieee80211_channel *chan, char *ssid) 770 { 771 struct ieee80211_node *ni, *best; 772 int hash; 773 int best_score, score; 774 775 best = NULL; 776 best_score = -1; 777 778 hash = IEEE80211_NODE_HASH(macaddr); 779 IEEE80211_NODE_LOCK(ic); 780 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 781 if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) 782 continue; 783 784 score = (ni->ni_chan == chan) ? 1 : 0; 785 786 if (ssid[1] == 0 || ni->ni_esslen == 0) 787 score++; 788 else if (ssid[1] != ni->ni_esslen || 789 memcmp(ssid + 2, ni->ni_essid, ssid[1]) != 0) 790 continue; 791 792 if (score > best_score) { 793 if (best != NULL) 794 (void)ieee80211_node_decref(best); 795 best = ieee80211_ref_node(ni); 796 best_score = score; 797 } 798 } 799 IEEE80211_NODE_UNLOCK(ic); 800 return best; 801 } 802 803 static void 804 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 805 { 806 IASSERT(ni != ic->ic_bss, ("freeing bss node")); 807 808 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 809 ("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr))); 810 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 811 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 812 LIST_REMOVE(ni, ni_hash); 813 ic->ic_nnodes--; 814 if (!IF_IS_EMPTY(&ni->ni_savedq)) { 815 IF_PURGE(&ni->ni_savedq); 816 if (ic->ic_set_tim) 817 (*ic->ic_set_tim)(ic, ni->ni_associd, 0); 818 } 819 if (TAILQ_EMPTY(&ic->ic_node)) 820 ic->ic_inact_timer = 0; 821 (*ic->ic_node_free)(ic, ni); 822 /* TBD indicate to drivers that a new node can be allocated */ 823 } 824 825 void 826 ieee80211_release_node(struct ieee80211com *ic, struct ieee80211_node *ni) 827 { 828 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 829 ("%s %s refcnt %d\n", __func__, 830 ether_sprintf(ni->ni_macaddr), ni->ni_refcnt)); 831 if (ieee80211_node_decref(ni) == 0 && 832 ni->ni_state == IEEE80211_STA_COLLECT) { 833 IEEE80211_NODE_LOCK_BH(ic); 834 ieee80211_free_node(ic, ni); 835 IEEE80211_NODE_UNLOCK_BH(ic); 836 } 837 } 838 839 void 840 ieee80211_free_allnodes(struct ieee80211com *ic) 841 { 842 struct ieee80211_node *ni; 843 844 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, ("free all nodes\n")); 845 IEEE80211_NODE_LOCK_BH(ic); 846 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) 847 ieee80211_free_node(ic, ni); 848 IEEE80211_NODE_UNLOCK_BH(ic); 849 850 if (ic->ic_bss != NULL) 851 node_cleanup(ic, ic->ic_bss); /* for station mode */ 852 } 853 854 /* 855 * Timeout inactive nodes. Note that we cannot hold the node 856 * lock while sending a frame as this would lead to a LOR. 857 * Instead we use a generation number to mark nodes that we've 858 * scanned and drop the lock and restart a scan if we have to 859 * time out a node. Since we are single-threaded by virtue of 860 * controlling the inactivity timer we can be sure this will 861 * process each node only once. 862 */ 863 void 864 ieee80211_clean_nodes(struct ieee80211com *ic) 865 { 866 struct ieee80211_node *ni; 867 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ 868 869 restart: 870 IEEE80211_NODE_LOCK(ic); 871 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) { 872 if (ic->ic_nnodes <= ic->ic_max_nnodes) 873 break; 874 if (ni->ni_scangen == gen) /* previously handled */ 875 continue; 876 ni->ni_scangen = gen; 877 if (ni->ni_refcnt > 0) 878 continue; 879 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 880 ("station %s purged from LRU cache\n", 881 ether_sprintf(ni->ni_macaddr))); 882 /* 883 * Send a deauthenticate frame. 884 * 885 * Drop the node lock before sending the 886 * deauthentication frame in case the driver takes 887 * a lock, as this will result in a LOR between the 888 * node lock and the driver lock. 889 */ 890 IEEE80211_NODE_UNLOCK(ic); 891 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 892 IEEE80211_SEND_MGMT(ic, ni, 893 IEEE80211_FC0_SUBTYPE_DEAUTH, 894 IEEE80211_REASON_AUTH_EXPIRE); 895 ieee80211_node_leave(ic, ni); 896 } else 897 ieee80211_free_node(ic, ni); 898 ic->ic_stats.is_node_timeout++; 899 goto restart; 900 } 901 IEEE80211_NODE_UNLOCK(ic); 902 } 903 904 void 905 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) 906 { 907 struct ieee80211_node *ni; 908 909 IEEE80211_NODE_LOCK(ic); 910 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) 911 (*f)(arg, ni); 912 IEEE80211_NODE_UNLOCK(ic); 913 } 914 915 void 916 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp) 917 { 918 int newassoc; 919 920 if (ni->ni_associd == 0) { 921 u_int16_t aid; 922 923 /* 924 * It would be clever to search the bitmap 925 * more efficiently, but this will do for now. 926 */ 927 for (aid = 1; aid < ic->ic_max_aid; aid++) { 928 if (!IEEE80211_AID_ISSET(aid, 929 ic->ic_aid_bitmap)) 930 break; 931 } 932 if (aid >= ic->ic_max_aid) { 933 IEEE80211_SEND_MGMT(ic, ni, resp, 934 IEEE80211_REASON_ASSOC_TOOMANY); 935 ieee80211_node_leave(ic, ni); 936 return; 937 } 938 ni->ni_associd = aid | 0xc000; 939 IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap); 940 newassoc = 1; 941 /* XXX for 11g must turn off short slot time if long 942 slot time sta associates */ 943 } else 944 newassoc = 0; 945 946 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG, 947 ("station %s %s associated at aid %d\n", 948 ether_sprintf(ni->ni_macaddr), 949 (newassoc ? "newly" : "already"), 950 ni->ni_associd & ~0xc000)); 951 952 /* give driver a chance to setup state like ni_txrate */ 953 if (ic->ic_newassoc) 954 (*ic->ic_newassoc)(ic, ni, newassoc); 955 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); 956 ieee80211_node_newstate(ni, IEEE80211_STA_ASSOC); 957 } 958 959 /* 960 * Handle bookkeeping for station deauthentication/disassociation 961 * when operating as an ap. 962 */ 963 void 964 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni) 965 { 966 967 IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP, 968 ("not in ap mode, mode %u", ic->ic_opmode)); 969 /* 970 * If node wasn't previously associated all 971 * we need to do is reclaim the reference. 972 */ 973 if (ni->ni_associd == 0) 974 return; 975 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 976 ni->ni_associd = 0; 977 ieee80211_node_newstate(ni, IEEE80211_STA_COLLECT); 978 } 979
Indexes created Wed Sep 24 02:09:48 GMT 2025