ieee80211_node.c revision 1.32
1 /* $NetBSD: ieee80211_node.c,v 1.32 2004/07/29 23:17:29 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 1.32 2004/07/29 23:17:29 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 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; 113 114 if (ic->ic_max_aid == 0) 115 ic->ic_max_aid = IEEE80211_AID_DEF; 116 else if (ic->ic_max_aid > IEEE80211_AID_MAX) 117 ic->ic_max_aid = IEEE80211_AID_MAX; 118 MALLOC(ic->ic_aid_bitmap, u_int32_t *, 119 howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t), 120 M_DEVBUF, M_NOWAIT | M_ZERO); 121 if (ic->ic_aid_bitmap == NULL) { 122 /* XXX no way to recover */ 123 printf("%s: no memory for AID bitmap!\n", __func__); 124 ic->ic_max_aid = 0; 125 } 126 } 127 128 void 129 ieee80211_node_lateattach(struct ieee80211com *ic) 130 { 131 struct ieee80211_node *ni; 132 133 ni = (*ic->ic_node_alloc)(ic); 134 IASSERT(ni != NULL, ("unable to setup inital BSS node")); 135 ni->ni_chan = IEEE80211_CHAN_ANYC; 136 ic->ic_bss = ni; 137 ic->ic_txpower = IEEE80211_TXPOWER_MAX; 138 } 139 140 void 141 ieee80211_node_detach(struct ieee80211com *ic) 142 { 143 144 if (ic->ic_bss != NULL) { 145 (*ic->ic_node_free)(ic, ic->ic_bss); 146 ic->ic_bss = NULL; 147 } 148 ieee80211_free_allnodes(ic); 149 IEEE80211_NODE_LOCK_DESTROY(ic); 150 if (ic->ic_aid_bitmap != NULL) 151 FREE(ic->ic_aid_bitmap, M_DEVBUF); 152 } 153 154 /* 155 * AP scanning support. 156 */ 157 158 /* 159 * Initialize the active channel set based on the set 160 * of available channels and the current PHY mode. 161 */ 162 static void 163 ieee80211_reset_scan(struct ieee80211com *ic) 164 { 165 166 memcpy(ic->ic_chan_scan, ic->ic_chan_active, 167 sizeof(ic->ic_chan_active)); 168 /* NB: hack, setup so next_scan starts with the first channel */ 169 if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC) 170 ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX]; 171 } 172 173 /* 174 * Begin an active scan. 175 */ 176 void 177 ieee80211_begin_scan(struct ieee80211com *ic) 178 { 179 180 /* 181 * In all but hostap mode scanning starts off in 182 * an active mode before switching to passive. 183 */ 184 if (ic->ic_opmode != IEEE80211_M_HOSTAP) { 185 ic->ic_flags |= IEEE80211_F_ASCAN; 186 ic->ic_stats.is_scan_active++; 187 } else 188 ic->ic_stats.is_scan_passive++; 189 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("begin %s scan\n", 190 (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive")); 191 /* 192 * Clear scan state and flush any previously seen 193 * AP's. Note that the latter assumes we don't act 194 * as both an AP and a station, otherwise we'll 195 * potentially flush state of stations associated 196 * with us. 197 */ 198 ieee80211_reset_scan(ic); 199 ieee80211_free_allnodes(ic); 200 201 /* Scan the next channel. */ 202 ieee80211_next_scan(ic); 203 } 204 205 /* 206 * Switch to the next channel marked for scanning. 207 */ 208 void 209 ieee80211_next_scan(struct ieee80211com *ic) 210 { 211 struct ieee80211_channel *chan; 212 213 chan = ic->ic_bss->ni_chan; 214 for (;;) { 215 if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX]) 216 chan = &ic->ic_channels[0]; 217 if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) { 218 /* 219 * Honor channels marked passive-only 220 * during an active scan. 221 */ 222 if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 || 223 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) 224 break; 225 } 226 if (chan == ic->ic_bss->ni_chan) { 227 ieee80211_end_scan(ic); 228 return; 229 } 230 } 231 clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan)); 232 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 233 ("%s: chan %d->%d\n", __func__, 234 ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan), 235 ieee80211_chan2ieee(ic, chan))); 236 ic->ic_bss->ni_chan = chan; 237 ieee80211_new_state(ic, IEEE80211_S_SCAN, -1); 238 } 239 240 void 241 ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan) 242 { 243 struct ieee80211_node *ni; 244 245 ni = ic->ic_bss; 246 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("creating ibss\n")); 247 ic->ic_flags |= IEEE80211_F_SIBSS; 248 ni->ni_chan = chan; 249 ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)]; 250 IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr); 251 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr); 252 if (ic->ic_opmode == IEEE80211_M_IBSS) { 253 if ((ic->ic_flags & IEEE80211_F_DESBSSID) != 0) 254 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid); 255 else 256 ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */ 257 } 258 ni->ni_esslen = ic->ic_des_esslen; 259 memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen); 260 ni->ni_rssi = 0; 261 ni->ni_rstamp = 0; 262 memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp)); 263 ni->ni_intval = ic->ic_lintval; 264 ni->ni_capinfo = IEEE80211_CAPINFO_IBSS; 265 if (ic->ic_flags & IEEE80211_F_PRIVACY) 266 ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY; 267 if (ic->ic_phytype == IEEE80211_T_FH) { 268 ni->ni_fhdwell = 200; /* XXX */ 269 ni->ni_fhindex = 1; 270 } 271 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 272 } 273 274 int 275 ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni) 276 { 277 u_int8_t rate; 278 int fail; 279 280 fail = 0; 281 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan))) 282 fail |= 0x01; 283 if (ic->ic_des_chan != IEEE80211_CHAN_ANYC && 284 ni->ni_chan != ic->ic_des_chan) 285 fail |= 0x01; 286 if (ic->ic_opmode == IEEE80211_M_IBSS) { 287 if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 288 fail |= 0x02; 289 } else { 290 if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0) 291 fail |= 0x02; 292 } 293 if (ic->ic_flags & IEEE80211_F_PRIVACY) { 294 if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 295 fail |= 0x04; 296 } else { 297 /* XXX does this mean privacy is supported or required? */ 298 if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) 299 fail |= 0x04; 300 } 301 rate = ieee80211_fix_rate(ic, ni, IEEE80211_F_DONEGO); 302 if (rate & IEEE80211_RATE_BASIC) 303 fail |= 0x08; 304 if (ic->ic_des_esslen != 0 && 305 (ni->ni_esslen != ic->ic_des_esslen || 306 memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0)) 307 fail |= 0x10; 308 if ((ic->ic_flags & IEEE80211_F_DESBSSID) && 309 !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid)) 310 fail |= 0x20; 311 #ifdef IEEE80211_DEBUG 312 if (ic->ic_if.if_flags & IFF_DEBUG) { 313 printf(" %c %s", fail ? '-' : '+', 314 ether_sprintf(ni->ni_macaddr)); 315 printf(" %s%c", ether_sprintf(ni->ni_bssid), 316 fail & 0x20 ? '!' : ' '); 317 printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan), 318 fail & 0x01 ? '!' : ' '); 319 printf(" %+4d", ni->ni_rssi); 320 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 321 fail & 0x08 ? '!' : ' '); 322 printf(" %4s%c", 323 (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 324 (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : 325 "????", 326 fail & 0x02 ? '!' : ' '); 327 printf(" %3s%c ", 328 (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 329 "wep" : "no", 330 fail & 0x04 ? '!' : ' '); 331 ieee80211_print_essid(ni->ni_essid, ni->ni_esslen); 332 printf("%s\n", fail & 0x10 ? "!" : ""); 333 } 334 #endif 335 return fail; 336 } 337 338 /* 339 * Complete a scan of potential channels. 340 */ 341 void 342 ieee80211_end_scan(struct ieee80211com *ic) 343 { 344 struct ieee80211_node *ni, *nextbs, *selbs; 345 int i, fail; 346 347 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, ("end %s scan\n", 348 (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive")); 349 350 ic->ic_flags &= ~IEEE80211_F_ASCAN; 351 ni = TAILQ_FIRST(&ic->ic_node); 352 353 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 354 /* XXX off stack? */ 355 u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)]; 356 /* 357 * The passive scan to look for existing AP's completed, 358 * select a channel to camp on. Identify the channels 359 * that already have one or more AP's and try to locate 360 * an unnoccupied one. If that fails, pick a random 361 * channel from the active set. 362 */ 363 for (; ni != NULL; ni = nextbs) { 364 ieee80211_ref_node(ni); 365 nextbs = TAILQ_NEXT(ni, ni_list); 366 setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan)); 367 ieee80211_free_node(ic, ni); 368 } 369 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 370 if (isset(ic->ic_chan_active, i) && isclr(occupied, i)) 371 break; 372 if (i == IEEE80211_CHAN_MAX) { 373 fail = arc4random() & 3; /* random 0-3 */ 374 for (i = 0; i < IEEE80211_CHAN_MAX; i++) 375 if (isset(ic->ic_chan_active, i) && fail-- == 0) 376 break; 377 } 378 ieee80211_create_ibss(ic, &ic->ic_channels[i]); 379 return; 380 } 381 if (ni == NULL) { 382 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 383 ("%s: no scan candidate\n", __func__)); 384 notfound: 385 if (ic->ic_opmode == IEEE80211_M_IBSS && 386 (ic->ic_flags & IEEE80211_F_IBSSON) && 387 ic->ic_des_esslen != 0) { 388 ieee80211_create_ibss(ic, ic->ic_ibss_chan); 389 return; 390 } 391 /* 392 * Reset the list of channels to scan and start again. 393 */ 394 ieee80211_reset_scan(ic); 395 ieee80211_next_scan(ic); 396 return; 397 } 398 selbs = NULL; 399 IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, 400 ("\tmacaddr bssid chan rssi rate flag wep essid\n")); 401 for (; ni != NULL; ni = nextbs) { 402 ieee80211_ref_node(ni); 403 nextbs = TAILQ_NEXT(ni, ni_list); 404 if (ni->ni_fails) { 405 /* 406 * The configuration of the access points may change 407 * during my scan. So delete the entry for the AP 408 * and retry to associate if there is another beacon. 409 */ 410 if (ni->ni_fails++ > 2) 411 ieee80211_free_node(ic, ni); 412 continue; 413 } 414 if (ieee80211_match_bss(ic, ni) == 0) { 415 if (selbs == NULL) 416 selbs = ni; 417 else if (ni->ni_rssi > selbs->ni_rssi) { 418 ieee80211_unref_node(&selbs); 419 selbs = ni; 420 } else 421 ieee80211_unref_node(&ni); 422 } else { 423 ieee80211_unref_node(&ni); 424 } 425 } 426 if (selbs == NULL) 427 goto notfound; 428 (*ic->ic_node_copy)(ic, ic->ic_bss, selbs); 429 if (ic->ic_opmode == IEEE80211_M_IBSS) { 430 ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE | 431 IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 432 if (ic->ic_bss->ni_rates.rs_nrates == 0) { 433 selbs->ni_fails++; 434 ieee80211_unref_node(&selbs); 435 goto notfound; 436 } 437 ieee80211_unref_node(&selbs); 438 /* 439 * Discard scan set; the nodes have a refcnt of zero 440 * and have not asked the driver to setup private 441 * node state. Let them be repopulated on demand either 442 * through transmission (ieee80211_find_txnode) or receipt 443 * of a probe response (to be added). 444 */ 445 ieee80211_free_allnodes(ic); 446 ieee80211_new_state(ic, IEEE80211_S_RUN, -1); 447 } else { 448 ieee80211_unref_node(&selbs); 449 ieee80211_new_state(ic, IEEE80211_S_AUTH, -1); 450 } 451 } 452 453 int 454 ieee80211_get_rate(struct ieee80211com *ic) 455 { 456 u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE]; 457 int rate; 458 459 rates = &ic->ic_bss->ni_rates.rs_rates; 460 461 if (ic->ic_fixed_rate != -1) 462 rate = (*rates)[ic->ic_fixed_rate]; 463 else if (ic->ic_state == IEEE80211_S_RUN) 464 rate = (*rates)[ic->ic_bss->ni_txrate]; 465 else 466 rate = 0; 467 468 return rate & IEEE80211_RATE_VAL; 469 } 470 471 static struct ieee80211_node * 472 ieee80211_node_alloc(struct ieee80211com *ic) 473 { 474 struct ieee80211_node *ni; 475 MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node), 476 M_80211_NODE, M_NOWAIT | M_ZERO); 477 return ni; 478 } 479 480 static void 481 node_cleanup(struct ieee80211com *ic, struct ieee80211_node *ni) 482 { 483 484 if (ni->ni_challenge != NULL) { 485 FREE(ni->ni_challenge, M_DEVBUF); 486 ni->ni_challenge = NULL; 487 } 488 } 489 490 static void 491 ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni) 492 { 493 node_cleanup(ic, ni); 494 FREE(ni, M_80211_NODE); 495 } 496 497 static void 498 ieee80211_node_copy(struct ieee80211com *ic, 499 struct ieee80211_node *dst, const struct ieee80211_node *src) 500 { 501 node_cleanup(ic, dst); 502 *dst = *src; 503 dst->ni_challenge = NULL; 504 } 505 506 static u_int8_t 507 ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni) 508 { 509 return ni->ni_rssi; 510 } 511 512 static void 513 ieee80211_setup_node(struct ieee80211com *ic, 514 struct ieee80211_node *ni, u_int8_t *macaddr) 515 { 516 int hash; 517 518 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 519 ("%s %s\n", __func__, ether_sprintf(macaddr))); 520 IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr); 521 hash = IEEE80211_NODE_HASH(macaddr); 522 ni->ni_refcnt = 1; /* mark referenced */ 523 524 IEEE80211_NODE_LOCK_BH(ic); 525 /* 526 * Note we don't enable the inactive timer when acting 527 * as a station. Nodes created in this mode represent 528 * AP's identified while scanning. If we time them out 529 * then several things happen: we can't return the data 530 * to users to show the list of AP's we encountered, and 531 * more importantly, we'll incorrectly deauthenticate 532 * ourself because the inactivity timer will kick us off. 533 */ 534 if (ic->ic_opmode != IEEE80211_M_STA && 535 TAILQ_EMPTY(&ic->ic_node)) 536 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 537 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 538 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); 539 IEEE80211_NODE_UNLOCK_BH(ic); 540 } 541 542 struct ieee80211_node * 543 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) 544 { 545 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 546 if (ni != NULL) 547 ieee80211_setup_node(ic, ni, macaddr); 548 else 549 ic->ic_stats.is_rx_nodealloc++; 550 return ni; 551 } 552 553 struct ieee80211_node * 554 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) 555 { 556 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 557 if (ni != NULL) { 558 ieee80211_setup_node(ic, ni, macaddr); 559 /* 560 * Inherit from ic_bss. 561 */ 562 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 563 ni->ni_chan = ic->ic_bss->ni_chan; 564 } else 565 ic->ic_stats.is_rx_nodealloc++; 566 return ni; 567 } 568 569 static struct ieee80211_node * 570 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 571 { 572 struct ieee80211_node *ni; 573 int hash; 574 575 IEEE80211_NODE_LOCK_ASSERT(ic); 576 577 hash = IEEE80211_NODE_HASH(macaddr); 578 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 579 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { 580 ieee80211_node_incref(ni); /* mark referenced */ 581 return ni; 582 } 583 } 584 return NULL; 585 } 586 587 struct ieee80211_node * 588 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 589 { 590 struct ieee80211_node *ni; 591 592 IEEE80211_NODE_LOCK(ic); 593 ni = _ieee80211_find_node(ic, macaddr); 594 IEEE80211_NODE_UNLOCK(ic); 595 return ni; 596 } 597 598 /* 599 * Return a reference to the appropriate node for sending 600 * a data frame. This handles node discovery in adhoc networks. 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 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 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 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 693 break; 694 } 695 break; 696 case IEEE80211_FC0_TYPE_DATA: 697 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { 698 case IEEE80211_FC1_DIR_NODS: 699 *bssid = wh->i_addr3; 700 if (ic->ic_opmode == IEEE80211_M_IBSS || 701 ic->ic_opmode == IEEE80211_M_AHDEMO) 702 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 703 break; 704 case IEEE80211_FC1_DIR_TODS: 705 *bssid = wh->i_addr1; 706 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 707 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 708 break; 709 case IEEE80211_FC1_DIR_FROMDS: 710 case IEEE80211_FC1_DIR_DSTODS: 711 *bssid = wh->i_addr2; 712 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); 713 break; 714 } 715 break; 716 } 717 return monitor || rc; 718 } 719 720 struct ieee80211_node * 721 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) 722 { 723 struct ieee80211_node *ni; 724 const static u_int8_t zero[IEEE80211_ADDR_LEN]; 725 u_int8_t *bssid; 726 727 if (!ieee80211_needs_rxnode(ic, wh, &bssid)) 728 return ieee80211_ref_node(ic->ic_bss); 729 730 IEEE80211_NODE_LOCK(ic); 731 ni = _ieee80211_find_node(ic, wh->i_addr2); 732 IEEE80211_NODE_UNLOCK(ic); 733 734 if (ni != NULL) 735 return ni; 736 737 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 738 return ieee80211_ref_node(ic->ic_bss); 739 740 /* XXX see remarks in ieee80211_find_txnode */ 741 /* XXX no rate negotiation; just dup */ 742 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) == NULL) 743 return ieee80211_ref_node(ic->ic_bss); 744 745 IEEE80211_ADDR_COPY(ni->ni_bssid, (bssid != NULL) ? bssid : zero); 746 747 ni->ni_rates = ic->ic_bss->ni_rates; 748 if (ic->ic_newassoc) 749 (*ic->ic_newassoc)(ic, ni, 1); 750 751 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 752 ("%s: faked-up node %p for %s\n", __func__, ni, 753 ether_sprintf(wh->i_addr2))); 754 755 return ieee80211_ref_node(ni); 756 } 757 758 /* 759 * Like find but search based on the channel too. 760 */ 761 struct ieee80211_node * 762 ieee80211_find_node_for_beacon(struct ieee80211com *ic, u_int8_t *macaddr, 763 struct ieee80211_channel *chan, char *ssid) 764 { 765 struct ieee80211_node *ni; 766 int hash; 767 768 hash = IEEE80211_NODE_HASH(macaddr); 769 IEEE80211_NODE_LOCK(ic); 770 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 771 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) && 772 ni->ni_chan == chan && 773 (ssid[1] == 0 || (ssid[1] == ni->ni_esslen && 774 !memcmp(ssid + 2, ni->ni_essid, ssid[1])))) { 775 ieee80211_node_incref(ni);/* mark referenced */ 776 break; 777 } 778 } 779 IEEE80211_NODE_UNLOCK(ic); 780 return ni; 781 } 782 783 static void 784 _ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 785 { 786 IASSERT(ni != ic->ic_bss, ("freeing bss node")); 787 788 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 789 ("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr))); 790 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 791 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 792 LIST_REMOVE(ni, ni_hash); 793 if (!IF_IS_EMPTY(&ni->ni_savedq)) { 794 IF_PURGE(&ni->ni_savedq); 795 if (ic->ic_set_tim) 796 (*ic->ic_set_tim)(ic, ni->ni_associd, 0); 797 } 798 if (TAILQ_EMPTY(&ic->ic_node)) 799 ic->ic_inact_timer = 0; 800 (*ic->ic_node_free)(ic, ni); 801 } 802 803 void 804 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 805 { 806 IASSERT(ni != ic->ic_bss, ("freeing ic_bss")); 807 808 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 809 ("%s %s refcnt %d\n", __func__, 810 ether_sprintf(ni->ni_macaddr), ni->ni_refcnt)); 811 if (ieee80211_node_decref(ni) == 0) { 812 IEEE80211_NODE_LOCK_BH(ic); 813 _ieee80211_free_node(ic, ni); 814 IEEE80211_NODE_UNLOCK_BH(ic); 815 } 816 } 817 818 void 819 ieee80211_free_allnodes(struct ieee80211com *ic) 820 { 821 struct ieee80211_node *ni; 822 823 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, ("free all nodes\n")); 824 IEEE80211_NODE_LOCK_BH(ic); 825 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) 826 _ieee80211_free_node(ic, ni); 827 IEEE80211_NODE_UNLOCK_BH(ic); 828 829 if (ic->ic_bss != NULL) 830 node_cleanup(ic, ic->ic_bss); /* for station mode */ 831 } 832 833 /* 834 * Timeout inactive nodes. Note that we cannot hold the node 835 * lock while sending a frame as this would lead to a LOR. 836 * Instead we use a generation number to mark nodes that we've 837 * scanned and drop the lock and restart a scan if we have to 838 * time out a node. Since we are single-threaded by virtue of 839 * controlling the inactivity timer we can be sure this will 840 * process each node only once. 841 */ 842 void 843 ieee80211_timeout_nodes(struct ieee80211com *ic) 844 { 845 struct ieee80211_node *ni; 846 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ 847 848 restart: 849 IEEE80211_NODE_LOCK(ic); 850 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) { 851 if (ni->ni_scangen == gen) /* previously handled */ 852 continue; 853 ni->ni_scangen = gen; 854 if (++ni->ni_inact > ieee80211_inact_max) { 855 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 856 ("station %s timed out due to inactivity (%u secs)\n", 857 ether_sprintf(ni->ni_macaddr), 858 ni->ni_inact)); 859 /* 860 * Send a deauthenticate frame. 861 * 862 * Drop the node lock before sending the 863 * deauthentication frame in case the driver takes 864 * a lock, as this will result in a LOR between the 865 * node lock and the driver lock. 866 */ 867 IEEE80211_NODE_UNLOCK(ic); 868 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 869 IEEE80211_SEND_MGMT(ic, ni, 870 IEEE80211_FC0_SUBTYPE_DEAUTH, 871 IEEE80211_REASON_AUTH_EXPIRE); 872 ieee80211_node_leave(ic, ni); 873 } else 874 ieee80211_free_node(ic, ni); 875 ic->ic_stats.is_node_timeout++; 876 goto restart; 877 } 878 } 879 if (!TAILQ_EMPTY(&ic->ic_node)) 880 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 881 IEEE80211_NODE_UNLOCK(ic); 882 } 883 884 void 885 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) 886 { 887 struct ieee80211_node *ni; 888 889 IEEE80211_NODE_LOCK(ic); 890 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) 891 (*f)(arg, ni); 892 IEEE80211_NODE_UNLOCK(ic); 893 } 894 895 void 896 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp) 897 { 898 int newassoc; 899 900 if (ni->ni_associd == 0) { 901 u_int16_t aid; 902 903 /* 904 * It would be clever to search the bitmap 905 * more efficiently, but this will do for now. 906 */ 907 for (aid = 1; aid < ic->ic_max_aid; aid++) { 908 if (!IEEE80211_AID_ISSET(aid, 909 ic->ic_aid_bitmap)) 910 break; 911 } 912 if (aid >= ic->ic_max_aid) { 913 IEEE80211_SEND_MGMT(ic, ni, resp, 914 IEEE80211_REASON_ASSOC_TOOMANY); 915 ieee80211_node_leave(ic, ni); 916 return; 917 } 918 ni->ni_associd = aid | 0xc000; 919 IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap); 920 newassoc = 1; 921 /* XXX for 11g must turn off short slot time if long 922 slot time sta associates */ 923 } else 924 newassoc = 0; 925 926 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG, 927 ("station %s %s associated at aid %d\n", 928 ether_sprintf(ni->ni_macaddr), 929 (newassoc ? "newly" : "already"), 930 ni->ni_associd & ~0xc000)); 931 932 /* give driver a chance to setup state like ni_txrate */ 933 if (ic->ic_newassoc) 934 (*ic->ic_newassoc)(ic, ni, newassoc); 935 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); 936 } 937 938 /* 939 * Handle bookkeeping for station deauthentication/disassociation 940 * when operating as an ap. 941 */ 942 void 943 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni) 944 { 945 946 IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP, 947 ("not in ap mode, mode %u", ic->ic_opmode)); 948 /* 949 * If node wasn't previously associated all 950 * we need to do is reclaim the reference. 951 */ 952 if (ni->ni_associd == 0) 953 goto done; 954 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 955 ni->ni_associd = 0; 956 957 done: 958 ieee80211_free_node(ic, ni); 959 } 960
Indexes created Tue Sep 23 14:10:03 GMT 2025