ieee80211_node.c revision 1.22
1 /* $NetBSD: ieee80211_node.c,v 1.22 2004/07/23 09:22:15 mycroft 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 1.22 2004/07/23 09:22:15 mycroft 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 if (ic->ic_max_aid == 0) 118 ic->ic_max_aid = IEEE80211_AID_DEF; 119 else if (ic->ic_max_aid > IEEE80211_AID_MAX) 120 ic->ic_max_aid = IEEE80211_AID_MAX; 121 MALLOC(ic->ic_aid_bitmap, u_int32_t *, 122 howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t), 123 M_DEVBUF, M_NOWAIT | M_ZERO); 124 if (ic->ic_aid_bitmap == NULL) { 125 /* XXX no way to recover */ 126 printf("%s: no memory for AID bitmap!\n", __func__); 127 ic->ic_max_aid = 0; 128 } 129 } 130 131 void 132 ieee80211_node_lateattach(struct ifnet *ifp) 133 { 134 struct ieee80211com *ic = (void *)ifp; 135 struct ieee80211_node *ni; 136 137 ni = (*ic->ic_node_alloc)(ic); 138 IASSERT(ni != NULL, ("unable to setup inital BSS node")); 139 ni->ni_chan = IEEE80211_CHAN_ANYC; 140 ic->ic_bss = ni; 141 ic->ic_txpower = IEEE80211_TXPOWER_MAX; 142 } 143 144 void 145 ieee80211_node_detach(struct ifnet *ifp) 146 { 147 struct ieee80211com *ic = (void *)ifp; 148 149 if (ic->ic_bss != NULL) 150 (*ic->ic_node_free)(ic, ic->ic_bss); 151 ieee80211_free_allnodes(ic); 152 #ifdef __FreeBSD__ 153 IEEE80211_NODE_LOCK_DESTROY(ic); 154 #endif 155 if (ic->ic_aid_bitmap != NULL) 156 FREE(ic->ic_aid_bitmap, M_DEVBUF); 157 } 158 159 /* 160 * AP scanning support. 161 */ 162 163 /* 164 * Initialize the active channel set based on the set 165 * of available channels and the current PHY mode. 166 */ 167 static void 168 ieee80211_reset_scan(struct ifnet *ifp) 169 { 170 struct ieee80211com *ic = (void *)ifp; 171 172 memcpy(ic->ic_chan_scan, ic->ic_chan_active, 173 sizeof(ic->ic_chan_active)); 174 /* NB: hack, setup so next_scan starts with the first channel */ 175 if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC) 176 ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX]; 177 } 178 179 /* 180 * Begin an active scan. 181 */ 182 void 183 ieee80211_begin_scan(struct ifnet *ifp) 184 { 185 struct ieee80211com *ic = (void *)ifp; 186 187 /* 188 * In all but hostap mode scanning starts off in 189 * an active mode before switching to passive. 190 */ 191 if (ic->ic_opmode != IEEE80211_M_HOSTAP) { 192 ic->ic_flags |= IEEE80211_F_ASCAN; 193 ic->ic_stats.is_scan_active++; 194 } else 195 ic->ic_stats.is_scan_passive++; 196 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("begin %s scan\n", 197 (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive")); 198 /* 199 * Clear scan state and flush any previously seen 200 * AP's. Note that the latter assumes we don't act 201 * as both an AP and a station, otherwise we'll 202 * potentially flush state of stations associated 203 * with us. 204 */ 205 ieee80211_reset_scan(ifp); 206 ieee80211_free_allnodes(ic); 207 208 /* Scan the next channel. */ 209 ieee80211_next_scan(ifp); 210 } 211 212 /* 213 * Switch to the next channel marked for scanning. 214 */ 215 void 216 ieee80211_next_scan(struct ifnet *ifp) 217 { 218 struct ieee80211com *ic = (void *)ifp; 219 struct ieee80211_channel *chan; 220 221 chan = ic->ic_bss->ni_chan; 222 for (;;) { 223 if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX]) 224 chan = &ic->ic_channels[0]; 225 if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) { 226 /* 227 * Honor channels marked passive-only 228 * during an active scan. 229 */ 230 if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 || 231 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) 232 break; 233 } 234 if (chan == ic->ic_bss->ni_chan) { 235 ieee80211_end_scan(ifp); 236 return; 237 } 238 } 239 clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan)); 240 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 241 ("%s: chan %d->%d\n", __func__, 242 ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan), 243 ieee80211_chan2ieee(ic, chan))); 244 ic->ic_bss->ni_chan = chan; 245 ieee80211_new_state(ic, IEEE80211_S_SCAN, -1); 246 } 247 248 void 249 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan) 250 { 251 struct ieee80211_node *ni; 252 253 ni = ic->ic_bss; 254 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("creating ibss\n")); 255 ic->ic_flags |= IEEE80211_F_SIBSS; 256 ni->ni_chan = chan; 257 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)]; 258 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr); 259 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr); 260 if (ic->ic_opmode == IEEE80211_M_IBSS) { 261 if ((ic->ic_flags & IEEE80211_F_DESBSSID) != 0) 262 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid); 263 else 264 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */ 265 } 266 ni->ni_esslen = ic->ic_des_esslen; 267 memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen); 268 ni->ni_rssi = 0; 269 ni->ni_rstamp = 0; 270 memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp)); 271 ni->ni_intval = ic->ic_lintval; 272 ni->ni_capinfo = IEEE80211_CAPINFO_IBSS; 273 if (ic->ic_flags & IEEE80211_F_PRIVACY) 274 ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY; 275 if (ic->ic_phytype == IEEE80211_T_FH) { 276 ni->ni_fhdwell = 200; /* XXX */ 277 ni->ni_fhindex = 1; 278 } 279 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 280 } 281 282 int 283 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni) 284 { 285 u_int8_t rate; 286 int fail; 287 288 fail = 0; 289 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan))) 290 fail |= 0x01; 291 if (ic->ic_des_chan != IEEE80211_CHAN_ANYC && 292 ni->ni_chan != ic->ic_des_chan) 293 fail |= 0x01; 294 if (ic->ic_opmode == IEEE80211_M_IBSS) { 295 if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 296 fail |= 0x02; 297 } else { 298 if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0) 299 fail |= 0x02; 300 } 301 if (ic->ic_flags & IEEE80211_F_PRIVACY) { 302 if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 303 fail |= 0x04; 304 } else { 305 /* XXX does this mean privacy is supported or required? */ 306 if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) 307 fail |= 0x04; 308 } 309 rate = ieee80211_fix_rate(ic, ni, IEEE80211_F_DONEGO); 310 if (rate & IEEE80211_RATE_BASIC) 311 fail |= 0x08; 312 if (ic->ic_des_esslen != 0 && 313 (ni->ni_esslen != ic->ic_des_esslen || 314 memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0)) 315 fail |= 0x10; 316 if ((ic->ic_flags & IEEE80211_F_DESBSSID) && 317 !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid)) 318 fail |= 0x20; 319 #ifdef IEEE80211_DEBUG 320 if (ic->ic_if.if_flags & IFF_DEBUG) { 321 printf(" %c %s", fail ? '-' : '+', 322 ether_sprintf(ni->ni_macaddr)); 323 printf(" %s%c", ether_sprintf(ni->ni_bssid), 324 fail & 0x20 ? '!' : ' '); 325 printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan), 326 fail & 0x01 ? '!' : ' '); 327 printf(" %+4d", ni->ni_rssi); 328 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 329 fail & 0x08 ? '!' : ' '); 330 printf(" %4s%c", 331 (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 332 (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : 333 "????", 334 fail & 0x02 ? '!' : ' '); 335 printf(" %3s%c ", 336 (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 337 "wep" : "no", 338 fail & 0x04 ? '!' : ' '); 339 ieee80211_print_essid(ni->ni_essid, ni->ni_esslen); 340 printf("%s\n", fail & 0x10 ? "!" : ""); 341 } 342 #endif 343 return fail; 344 } 345 346 /* 347 * Complete a scan of potential channels. 348 */ 349 void 350 ieee80211_end_scan(struct ifnet *ifp) 351 { 352 struct ieee80211com *ic = (void *)ifp; 353 struct ieee80211_node *ni, *nextbs, *selbs; 354 int i, fail; 355 356 ic->ic_flags &= ~IEEE80211_F_ASCAN; 357 ni = TAILQ_FIRST(&ic->ic_node); 358 359 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 360 /* XXX off stack? */ 361 u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)]; 362 /* 363 * The passive scan to look for existing AP's completed, 364 * select a channel to camp on. Identify the channels 365 * that already have one or more AP's and try to locate 366 * an unnoccupied one. If that fails, pick a random 367 * channel from the active set. 368 */ 369 for (; ni != NULL; ni = nextbs) { 370 ieee80211_ref_node(ni); 371 nextbs = TAILQ_NEXT(ni, ni_list); 372 setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan)); 373 ieee80211_free_node(ic, ni); 374 } 375 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 376 if (isset(ic->ic_chan_active, i) && isclr(occupied, i)) 377 break; 378 if (i == IEEE80211_CHAN_MAX) { 379 fail = arc4random() & 3; /* random 0-3 */ 380 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 381 if (isset(ic->ic_chan_active, i) && fail-- == 0) 382 break; 383 } 384 ieee80211_create_ibss(ic, &ic->ic_channels[i]); 385 return; 386 } 387 if (ni == NULL) { 388 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 389 ("%s: no scan candidate\n", __func__)); 390 notfound: 391 if (ic->ic_opmode == IEEE80211_M_IBSS && 392 (ic->ic_flags & IEEE80211_F_IBSSON) && 393 ic->ic_des_esslen != 0) { 394 ieee80211_create_ibss(ic, ic->ic_ibss_chan); 395 return; 396 } 397 /* 398 * Reset the list of channels to scan and start again. 399 */ 400 ieee80211_reset_scan(ifp); 401 ieee80211_next_scan(ifp); 402 return; 403 } 404 selbs = NULL; 405 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 406 ("\tmacaddr bssid chan rssi rate flag wep essid\n")); 407 for (; ni != NULL; ni = nextbs) { 408 ieee80211_ref_node(ni); 409 nextbs = TAILQ_NEXT(ni, ni_list); 410 if (ni->ni_fails) { 411 /* 412 * The configuration of the access points may change 413 * during my scan. So delete the entry for the AP 414 * and retry to associate if there is another beacon. 415 */ 416 if (ni->ni_fails++ > 2) 417 ieee80211_free_node(ic, ni); 418 continue; 419 } 420 if (ieee80211_match_bss(ic, ni) == 0) { 421 if (selbs == NULL) 422 selbs = ni; 423 else if (ni->ni_rssi > selbs->ni_rssi) { 424 ieee80211_unref_node(&selbs); 425 selbs = ni; 426 } else 427 ieee80211_unref_node(&ni); 428 } else { 429 ieee80211_unref_node(&ni); 430 } 431 } 432 if (selbs == NULL) 433 goto notfound; 434 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs); 435 if (ic->ic_opmode == IEEE80211_M_IBSS) { 436 ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE | 437 IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 438 if (ic->ic_bss->ni_rates.rs_nrates == 0) { 439 selbs->ni_fails++; 440 ieee80211_unref_node(&selbs); 441 goto notfound; 442 } 443 ieee80211_unref_node(&selbs); 444 /* 445 * Discard scan set; the nodes have a refcnt of zero 446 * and have not asked the driver to setup private 447 * node state. Let them be repopulated on demand either 448 * through transmission (ieee80211_find_txnode) or receipt 449 * of a probe response (to be added). 450 */ 451 ieee80211_free_allnodes(ic); 452 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 453 } else { 454 ieee80211_unref_node(&selbs); 455 ieee80211_new_state(ic, IEEE80211_S_AUTH, -1); 456 } 457 } 458 459 int 460 ieee80211_get_rate(struct ieee80211com *ic) 461 { 462 u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE]; 463 int rate; 464 465 rates = &ic->ic_bss->ni_rates.rs_rates; 466 467 if (ic->ic_fixed_rate != -1) 468 rate = (*rates)[ic->ic_fixed_rate]; 469 else if (ic->ic_state == IEEE80211_S_RUN) 470 rate = (*rates)[ic->ic_bss->ni_txrate]; 471 else 472 rate = 0; 473 474 return rate & IEEE80211_RATE_VAL; 475 } 476 477 static struct ieee80211_node * 478 ieee80211_node_alloc(struct ieee80211com *ic) 479 { 480 struct ieee80211_node *ni; 481 MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node), 482 M_80211_NODE, M_NOWAIT | M_ZERO); 483 return ni; 484 } 485 486 static void 487 node_cleanup(struct ieee80211com *ic, struct ieee80211_node *ni) 488 { 489 490 if (ni->ni_challenge != NULL) { 491 FREE(ni->ni_challenge, M_DEVBUF); 492 ni->ni_challenge = NULL; 493 } 494 } 495 496 static void 497 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni) 498 { 499 node_cleanup(ic, ni); 500 FREE(ni, M_80211_NODE); 501 } 502 503 static void 504 ieee80211_node_copy(struct ieee80211com *ic, 505 struct ieee80211_node *dst, const struct ieee80211_node *src) 506 { 507 node_cleanup(ic, dst); 508 *dst = *src; 509 dst->ni_challenge = NULL; 510 } 511 512 static u_int8_t 513 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni) 514 { 515 return ni->ni_rssi; 516 } 517 518 static void 519 ieee80211_setup_node(struct ieee80211com *ic, 520 struct ieee80211_node *ni, u_int8_t *macaddr) 521 { 522 int hash; 523 ieee80211_node_critsec_decl(s); 524 525 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr); 526 hash = IEEE80211_NODE_HASH(macaddr); 527 ni->ni_refcnt = 1; /* mark referenced */ 528 ieee80211_node_critsec_begin(ic, s); 529 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 530 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); 531 /* 532 * Note we don't enable the inactive timer when acting 533 * as a station. Nodes created in this mode represent 534 * AP's identified while scanning. If we time them out 535 * then several things happen: we can't return the data 536 * to users to show the list of AP's we encountered, and 537 * more importantly, we'll incorrectly deauthenticate 538 * ourself because the inactivity timer will kick us off. 539 */ 540 if (ic->ic_opmode != IEEE80211_M_STA) 541 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 542 ieee80211_node_critsec_end(ic, s); 543 } 544 545 struct ieee80211_node * 546 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) 547 { 548 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 549 if (ni != NULL) 550 ieee80211_setup_node(ic, ni, macaddr); 551 else 552 ic->ic_stats.is_rx_nodealloc++; 553 return ni; 554 } 555 556 struct ieee80211_node * 557 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) 558 { 559 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 560 if (ni != NULL) { 561 ieee80211_setup_node(ic, ni, macaddr); 562 /* 563 * Inherit from ic_bss. 564 */ 565 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 566 ni->ni_chan = ic->ic_bss->ni_chan; 567 } else 568 ic->ic_stats.is_rx_nodealloc++; 569 return ni; 570 } 571 572 static struct ieee80211_node * 573 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 574 { 575 struct ieee80211_node *ni; 576 int hash; 577 578 #ifdef __FreeBSD__ 579 IEEE80211_NODE_LOCK_ASSERT(ic); 580 #endif /* __FreeBSD__ */ 581 582 hash = IEEE80211_NODE_HASH(macaddr); 583 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 584 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { 585 ieee80211_node_incref(ni); /* mark referenced */ 586 return ni; 587 } 588 } 589 return NULL; 590 } 591 592 struct ieee80211_node * 593 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 594 { 595 struct ieee80211_node *ni; 596 ieee80211_node_critsec_decl(s); 597 598 ieee80211_node_critsec_begin(ic, s); 599 ni = _ieee80211_find_node(ic, macaddr); 600 ieee80211_node_critsec_end(ic, s); 601 return ni; 602 } 603 604 /* 605 * Return a reference to the appropriate node for sending 606 * a data frame. This handles node discovery in adhoc networks. 607 */ 608 struct ieee80211_node * 609 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr) 610 { 611 struct ieee80211_node *ni; 612 ieee80211_node_critsec_decl(s); 613 614 /* 615 * The destination address should be in the node table 616 * unless we are operating in station mode or this is a 617 * multicast/broadcast frame. 618 */ 619 if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr)) 620 return ic->ic_bss; 621 622 /* XXX can't hold lock across dup_bss 'cuz of recursive locking */ 623 ieee80211_node_critsec_begin(ic, s); 624 ni = _ieee80211_find_node(ic, macaddr); 625 ieee80211_node_critsec_end(ic, s); 626 if (ni == NULL && 627 (ic->ic_opmode == IEEE80211_M_IBSS || 628 ic->ic_opmode == IEEE80211_M_AHDEMO)) { 629 /* 630 * Fake up a node; this handles node discovery in 631 * adhoc mode. Note that for the driver's benefit 632 * we we treat this like an association so the driver 633 * has an opportunity to setup it's private state. 634 * 635 * XXX need better way to handle this; issue probe 636 * request so we can deduce rate set, etc. 637 */ 638 ni = ieee80211_dup_bss(ic, macaddr); 639 if (ni != NULL) { 640 /* XXX no rate negotiation; just dup */ 641 ni->ni_rates = ic->ic_bss->ni_rates; 642 if (ic->ic_newassoc) 643 (*ic->ic_newassoc)(ic, ni, 1); 644 } 645 } 646 return ni; 647 } 648 649 /* 650 * For some types of packet and for some operating modes, it is 651 * desirable to process a Rx packet using its sender's node-record 652 * instead of the BSS record, when that is possible. 653 * 654 * - AP mode: keep a node-record for every authenticated/associated 655 * station *in the BSS*. For future use, we also track neighboring 656 * APs, since they might belong to the same ESSID. 657 * 658 * - IBSS mode: keep a node-record for every station *in the BSS*. 659 * 660 * - monitor mode: keep a node-record for every sender, regardless 661 * of BSS. 662 * 663 * - STA mode: the only available node-record is the BSS record, 664 * ic->ic_bss. 665 * 666 * Of all the 802.11 Control packets, only the node-records for 667 * RTS packets node-record can be looked up. 668 * 669 * Return non-zero if the packet's node-record is kept, zero 670 * otherwise. 671 */ 672 static __inline int 673 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh, 674 u_int8_t **bssid) 675 { 676 struct ieee80211_node *bss = ic->ic_bss; 677 int monitor, rc = 0; 678 679 monitor = (ic->ic_opmode == IEEE80211_M_MONITOR); 680 681 *bssid = NULL; 682 683 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) { 684 case IEEE80211_FC0_TYPE_CTL: 685 if (!monitor) 686 break; 687 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == 688 IEEE80211_FC0_SUBTYPE_RTS; 689 case IEEE80211_FC0_TYPE_MGT: 690 *bssid = wh->i_addr3; 691 switch (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) { 692 case IEEE80211_FC0_SUBTYPE_BEACON: 693 case IEEE80211_FC0_SUBTYPE_PROBE_RESP: 694 rc = 1; 695 break; 696 default: 697 break; 698 } 699 break; 700 case IEEE80211_FC0_TYPE_DATA: 701 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { 702 case IEEE80211_FC1_DIR_NODS: 703 *bssid = wh->i_addr3; 704 if (ic->ic_opmode == IEEE80211_M_IBSS || 705 ic->ic_opmode == IEEE80211_M_AHDEMO) 706 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 707 break; 708 case IEEE80211_FC1_DIR_TODS: 709 *bssid = wh->i_addr1; 710 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 711 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 712 break; 713 case IEEE80211_FC1_DIR_FROMDS: 714 case IEEE80211_FC1_DIR_DSTODS: 715 *bssid = wh->i_addr2; 716 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); 717 break; 718 } 719 break; 720 } 721 return monitor || rc; 722 } 723 724 struct ieee80211_node * 725 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) 726 { 727 struct ieee80211_node *ni; 728 const static u_int8_t zero[IEEE80211_ADDR_LEN]; 729 u_int8_t *bssid; 730 ieee80211_node_critsec_decl(s); 731 732 if (!ieee80211_needs_rxnode(ic, wh, &bssid)) 733 return ieee80211_ref_node(ic->ic_bss); 734 735 ieee80211_node_critsec_begin(ic, s); 736 ni = _ieee80211_find_node(ic, wh->i_addr2); 737 ieee80211_node_critsec_end(ic, s); 738 739 if (ni != NULL) 740 return 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 struct ieee80211_node * 767 ieee80211_lookup_node(struct ieee80211com *ic, 768 u_int8_t *macaddr, struct ieee80211_channel *chan) 769 { 770 struct ieee80211_node *ni; 771 int hash; 772 ieee80211_node_critsec_decl(s); 773 774 hash = IEEE80211_NODE_HASH(macaddr); 775 ieee80211_node_critsec_begin(ic, s); 776 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 777 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) && 778 ni->ni_chan == chan) { 779 ieee80211_node_incref(ni);/* mark referenced */ 780 break; 781 } 782 } 783 ieee80211_node_critsec_end(ic, s); 784 return ni; 785 } 786 787 static void 788 _ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 789 { 790 IASSERT(ni != ic->ic_bss, ("freeing bss node")); 791 792 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 793 ("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr))); 794 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 795 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 796 LIST_REMOVE(ni, ni_hash); 797 if (!IF_IS_EMPTY(&ni->ni_savedq)) { 798 IF_PURGE(&ni->ni_savedq); 799 if (ic->ic_set_tim) 800 (*ic->ic_set_tim)(ic, ni->ni_associd, 0); 801 } 802 if (TAILQ_EMPTY(&ic->ic_node)) 803 ic->ic_inact_timer = 0; 804 (*ic->ic_node_free)(ic, ni); 805 } 806 807 void 808 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 809 { 810 ieee80211_node_critsec_decl(s); 811 812 IASSERT(ni != ic->ic_bss, ("freeing ic_bss")); 813 814 if (ieee80211_node_decref(ni) == 0) { 815 ieee80211_node_critsec_begin(ic, s); 816 _ieee80211_free_node(ic, ni); 817 ieee80211_node_critsec_end(ic, s); 818 } 819 } 820 821 void 822 ieee80211_free_allnodes(struct ieee80211com *ic) 823 { 824 struct ieee80211_node *ni; 825 ieee80211_node_critsec_decl(s); 826 827 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, ("free all nodes\n")); 828 ieee80211_node_critsec_begin(ic, s); 829 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) 830 _ieee80211_free_node(ic, ni); 831 ieee80211_node_critsec_end(ic, s); 832 833 if (ic->ic_bss != NULL) 834 node_cleanup(ic, ic->ic_bss); /* for station mode */ 835 } 836 837 /* 838 * Timeout inactive nodes. Note that we cannot hold the node 839 * lock while sending a frame as this would lead to a LOR. 840 * Instead we use a generation number to mark nodes that we've 841 * scanned and drop the lock and restart a scan if we have to 842 * time out a node. Since we are single-threaded by virtue of 843 * controlling the inactivity timer we can be sure this will 844 * process each node only once. 845 */ 846 void 847 ieee80211_timeout_nodes(struct ieee80211com *ic) 848 { 849 struct ieee80211_node *ni; 850 ieee80211_node_critsec_decl(s); 851 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ 852 853 restart: 854 ieee80211_node_critsec_begin(ic, s); 855 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) { 856 if (ni->ni_scangen == gen) /* previously handled */ 857 continue; 858 ni->ni_scangen = gen; 859 if (++ni->ni_inact > ieee80211_inact_max) { 860 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 861 ("station %s timed out due to inactivity (%u secs)\n", 862 ether_sprintf(ni->ni_macaddr), 863 ni->ni_inact)); 864 /* 865 * Send a deauthenticate frame. 866 * 867 * Drop the node lock before sending the 868 * deauthentication frame in case the driver takes 869 * a lock, as this will result in a LOR between the 870 * node lock and the driver lock. 871 */ 872 ieee80211_node_critsec_end(ic, s); 873 IEEE80211_SEND_MGMT(ic, ni, 874 IEEE80211_FC0_SUBTYPE_DEAUTH, 875 IEEE80211_REASON_AUTH_EXPIRE); 876 ieee80211_node_leave(ic, ni); 877 ic->ic_stats.is_node_timeout++; 878 goto restart; 879 } 880 } 881 if (!TAILQ_EMPTY(&ic->ic_node)) 882 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 883 ieee80211_node_critsec_end(ic, s); 884 } 885 886 void 887 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) 888 { 889 struct ieee80211_node *ni; 890 ieee80211_node_critsec_decl(s); 891 892 ieee80211_node_critsec_begin(ic, s); 893 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) 894 (*f)(arg, ni); 895 ieee80211_node_critsec_end(ic, s); 896 } 897 898 void 899 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp) 900 { 901 int newassoc; 902 903 if (ni->ni_associd == 0) { 904 u_int16_t aid; 905 906 /* 907 * It would be clever to search the bitmap 908 * more efficiently, but this will do for now. 909 */ 910 for (aid = 1; aid < ic->ic_max_aid; aid++) { 911 if (!IEEE80211_AID_ISSET(aid, 912 ic->ic_aid_bitmap)) 913 break; 914 } 915 if (aid >= ic->ic_max_aid) { 916 IEEE80211_SEND_MGMT(ic, ni, resp, 917 IEEE80211_REASON_ASSOC_TOOMANY); 918 ieee80211_node_leave(ic, ni); 919 return; 920 } 921 ni->ni_associd = aid | 0xc000; 922 IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap); 923 newassoc = 1; 924 /* XXX for 11g must turn off short slot time if long 925 slot time sta associates */ 926 } else 927 newassoc = 0; 928 929 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG, 930 ("station %s %s associated at aid %d\n", 931 ether_sprintf(ni->ni_macaddr), 932 (newassoc ? "newly" : "already"), 933 ni->ni_associd & ~0xc000)); 934 935 /* give driver a chance to setup state like ni_txrate */ 936 if (ic->ic_newassoc) 937 (*ic->ic_newassoc)(ic, ni, newassoc); 938 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); 939 } 940 941 /* 942 * Handle bookkeeping for station deauthentication/disassociation 943 * when operating as an ap. 944 */ 945 void 946 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni) 947 { 948 949 IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP, 950 ("not in ap mode, mode %u", ic->ic_opmode)); 951 /* 952 * If node wasn't previously associated all 953 * we need to do is reclaim the reference. 954 */ 955 if (ni->ni_associd == 0) 956 goto done; 957 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 958 ni->ni_associd = 0; 959 960 done: 961 ieee80211_free_node(ic, ni); 962 } 963
Indexes created Wed Sep 24 02:09:48 GMT 2025