ieee80211_node.c revision 1.23
1 /* $NetBSD: ieee80211_node.c,v 1.23 2004/07/23 10:15:13 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 1.23 2004/07/23 10:15:13 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 TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); 526 LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); 527 /* 528 * Note we don't enable the inactive timer when acting 529 * as a station. Nodes created in this mode represent 530 * AP's identified while scanning. If we time them out 531 * then several things happen: we can't return the data 532 * to users to show the list of AP's we encountered, and 533 * more importantly, we'll incorrectly deauthenticate 534 * ourself because the inactivity timer will kick us off. 535 */ 536 if (ic->ic_opmode != IEEE80211_M_STA) 537 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 538 IEEE80211_NODE_UNLOCK_BH(ic); 539 } 540 541 struct ieee80211_node * 542 ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) 543 { 544 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 545 if (ni != NULL) 546 ieee80211_setup_node(ic, ni, macaddr); 547 else 548 ic->ic_stats.is_rx_nodealloc++; 549 return ni; 550 } 551 552 struct ieee80211_node * 553 ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) 554 { 555 struct ieee80211_node *ni = (*ic->ic_node_alloc)(ic); 556 if (ni != NULL) { 557 ieee80211_setup_node(ic, ni, macaddr); 558 /* 559 * Inherit from ic_bss. 560 */ 561 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 562 ni->ni_chan = ic->ic_bss->ni_chan; 563 } else 564 ic->ic_stats.is_rx_nodealloc++; 565 return ni; 566 } 567 568 static struct ieee80211_node * 569 _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 570 { 571 struct ieee80211_node *ni; 572 int hash; 573 574 IEEE80211_NODE_LOCK_ASSERT(ic); 575 576 hash = IEEE80211_NODE_HASH(macaddr); 577 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 578 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { 579 ieee80211_node_incref(ni); /* mark referenced */ 580 return ni; 581 } 582 } 583 return NULL; 584 } 585 586 struct ieee80211_node * 587 ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) 588 { 589 struct ieee80211_node *ni; 590 591 IEEE80211_NODE_LOCK(ic); 592 ni = _ieee80211_find_node(ic, macaddr); 593 IEEE80211_NODE_UNLOCK(ic); 594 return ni; 595 } 596 597 /* 598 * Return a reference to the appropriate node for sending 599 * a data frame. This handles node discovery in adhoc networks. 600 */ 601 struct ieee80211_node * 602 ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr) 603 { 604 struct ieee80211_node *ni; 605 606 /* 607 * The destination address should be in the node table 608 * unless we are operating in station mode or this is a 609 * multicast/broadcast frame. 610 */ 611 if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr)) 612 return ic->ic_bss; 613 614 /* XXX can't hold lock across dup_bss 'cuz of recursive locking */ 615 IEEE80211_NODE_LOCK(ic); 616 ni = _ieee80211_find_node(ic, macaddr); 617 IEEE80211_NODE_UNLOCK(ic); 618 if (ni == NULL && 619 (ic->ic_opmode == IEEE80211_M_IBSS || 620 ic->ic_opmode == IEEE80211_M_AHDEMO)) { 621 /* 622 * Fake up a node; this handles node discovery in 623 * adhoc mode. Note that for the driver's benefit 624 * we we treat this like an association so the driver 625 * has an opportunity to setup it's private state. 626 * 627 * XXX need better way to handle this; issue probe 628 * request so we can deduce rate set, etc. 629 */ 630 ni = ieee80211_dup_bss(ic, macaddr); 631 if (ni != NULL) { 632 /* XXX no rate negotiation; just dup */ 633 ni->ni_rates = ic->ic_bss->ni_rates; 634 if (ic->ic_newassoc) 635 (*ic->ic_newassoc)(ic, ni, 1); 636 } 637 } 638 return ni; 639 } 640 641 /* 642 * For some types of packet and for some operating modes, it is 643 * desirable to process a Rx packet using its sender's node-record 644 * instead of the BSS record, when that is possible. 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 ESSID. 649 * 650 * - IBSS mode: keep a node-record for every station *in the BSS*. 651 * 652 * - monitor mode: keep a node-record for every sender, regardless 653 * of BSS. 654 * 655 * - STA mode: the only available node-record is the BSS record, 656 * ic->ic_bss. 657 * 658 * Of all the 802.11 Control packets, only the node-records for 659 * RTS packets node-record can be looked up. 660 * 661 * Return non-zero if the packet's node-record is kept, zero 662 * otherwise. 663 */ 664 static __inline int 665 ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh, 666 u_int8_t **bssid) 667 { 668 struct ieee80211_node *bss = ic->ic_bss; 669 int monitor, rc = 0; 670 671 monitor = (ic->ic_opmode == IEEE80211_M_MONITOR); 672 673 *bssid = NULL; 674 675 switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) { 676 case IEEE80211_FC0_TYPE_CTL: 677 if (!monitor) 678 break; 679 return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == 680 IEEE80211_FC0_SUBTYPE_RTS; 681 case IEEE80211_FC0_TYPE_MGT: 682 *bssid = wh->i_addr3; 683 switch (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) { 684 case IEEE80211_FC0_SUBTYPE_BEACON: 685 case IEEE80211_FC0_SUBTYPE_PROBE_RESP: 686 rc = 1; 687 break; 688 default: 689 break; 690 } 691 break; 692 case IEEE80211_FC0_TYPE_DATA: 693 switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { 694 case IEEE80211_FC1_DIR_NODS: 695 *bssid = wh->i_addr3; 696 if (ic->ic_opmode == IEEE80211_M_IBSS || 697 ic->ic_opmode == IEEE80211_M_AHDEMO) 698 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 699 break; 700 case IEEE80211_FC1_DIR_TODS: 701 *bssid = wh->i_addr1; 702 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 703 rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); 704 break; 705 case IEEE80211_FC1_DIR_FROMDS: 706 case IEEE80211_FC1_DIR_DSTODS: 707 *bssid = wh->i_addr2; 708 rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); 709 break; 710 } 711 break; 712 } 713 return monitor || rc; 714 } 715 716 struct ieee80211_node * 717 ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) 718 { 719 struct ieee80211_node *ni; 720 const static u_int8_t zero[IEEE80211_ADDR_LEN]; 721 u_int8_t *bssid; 722 723 if (!ieee80211_needs_rxnode(ic, wh, &bssid)) 724 return ieee80211_ref_node(ic->ic_bss); 725 726 IEEE80211_NODE_LOCK(ic); 727 ni = _ieee80211_find_node(ic, wh->i_addr2); 728 IEEE80211_NODE_UNLOCK(ic); 729 730 if (ni != NULL) 731 return ni; 732 733 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 734 return ieee80211_ref_node(ic->ic_bss); 735 736 /* XXX see remarks in ieee80211_find_txnode */ 737 /* XXX no rate negotiation; just dup */ 738 if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) == NULL) 739 return ieee80211_ref_node(ic->ic_bss); 740 741 IEEE80211_ADDR_COPY(ni->ni_bssid, (bssid != NULL) ? bssid : zero); 742 743 ni->ni_rates = ic->ic_bss->ni_rates; 744 if (ic->ic_newassoc) 745 (*ic->ic_newassoc)(ic, ni, 1); 746 747 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 748 ("%s: faked-up node %p for %s\n", __func__, ni, 749 ether_sprintf(wh->i_addr2))); 750 751 return ieee80211_ref_node(ni); 752 } 753 754 /* 755 * Like find but search based on the channel too. 756 */ 757 struct ieee80211_node * 758 ieee80211_find_node_with_channel(struct ieee80211com *ic, u_int8_t *macaddr, 759 struct ieee80211_channel *chan) 760 { 761 struct ieee80211_node *ni; 762 int hash; 763 764 hash = IEEE80211_NODE_HASH(macaddr); 765 IEEE80211_NODE_LOCK(ic); 766 LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { 767 if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) && 768 ni->ni_chan == chan) { 769 ieee80211_node_incref(ni);/* mark referenced */ 770 break; 771 } 772 } 773 IEEE80211_NODE_UNLOCK(ic); 774 return ni; 775 } 776 777 static void 778 _ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 779 { 780 IASSERT(ni != ic->ic_bss, ("freeing bss node")); 781 782 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 783 ("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr))); 784 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 785 TAILQ_REMOVE(&ic->ic_node, ni, ni_list); 786 LIST_REMOVE(ni, ni_hash); 787 if (!IF_IS_EMPTY(&ni->ni_savedq)) { 788 IF_PURGE(&ni->ni_savedq); 789 if (ic->ic_set_tim) 790 (*ic->ic_set_tim)(ic, ni->ni_associd, 0); 791 } 792 if (TAILQ_EMPTY(&ic->ic_node)) 793 ic->ic_inact_timer = 0; 794 (*ic->ic_node_free)(ic, ni); 795 } 796 797 void 798 ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) 799 { 800 IASSERT(ni != ic->ic_bss, ("freeing ic_bss")); 801 802 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 803 ("%s %s refcnt %d\n", __func__, 804 ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni))); 805 if (ieee80211_node_decref(ni) == 0) { 806 IEEE80211_NODE_LOCK_BH(ic); 807 _ieee80211_free_node(ic, ni); 808 IEEE80211_NODE_UNLOCK_BH(ic); 809 } 810 } 811 812 void 813 ieee80211_free_allnodes(struct ieee80211com *ic) 814 { 815 struct ieee80211_node *ni; 816 817 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, ("free all nodes\n")); 818 IEEE80211_NODE_LOCK_BH(ic); 819 while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) 820 _ieee80211_free_node(ic, ni); 821 IEEE80211_NODE_UNLOCK_BH(ic); 822 823 if (ic->ic_bss != NULL) 824 node_cleanup(ic, ic->ic_bss); /* for station mode */ 825 } 826 827 /* 828 * Timeout inactive nodes. Note that we cannot hold the node 829 * lock while sending a frame as this would lead to a LOR. 830 * Instead we use a generation number to mark nodes that we've 831 * scanned and drop the lock and restart a scan if we have to 832 * time out a node. Since we are single-threaded by virtue of 833 * controlling the inactivity timer we can be sure this will 834 * process each node only once. 835 */ 836 void 837 ieee80211_timeout_nodes(struct ieee80211com *ic) 838 { 839 struct ieee80211_node *ni; 840 u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ 841 842 restart: 843 IEEE80211_NODE_LOCK(ic); 844 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) { 845 if (ni->ni_scangen == gen) /* previously handled */ 846 continue; 847 ni->ni_scangen = gen; 848 if (++ni->ni_inact > ieee80211_inact_max) { 849 IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE, 850 ("station %s timed out due to inactivity (%u secs)\n", 851 ether_sprintf(ni->ni_macaddr), 852 ni->ni_inact)); 853 /* 854 * Send a deauthenticate frame. 855 * 856 * Drop the node lock before sending the 857 * deauthentication frame in case the driver takes 858 * a lock, as this will result in a LOR between the 859 * node lock and the driver lock. 860 */ 861 IEEE80211_NODE_UNLOCK(ic); 862 IEEE80211_SEND_MGMT(ic, ni, 863 IEEE80211_FC0_SUBTYPE_DEAUTH, 864 IEEE80211_REASON_AUTH_EXPIRE); 865 ieee80211_node_leave(ic, ni); 866 ic->ic_stats.is_node_timeout++; 867 goto restart; 868 } 869 } 870 if (!TAILQ_EMPTY(&ic->ic_node)) 871 ic->ic_inact_timer = IEEE80211_INACT_WAIT; 872 IEEE80211_NODE_UNLOCK(ic); 873 } 874 875 void 876 ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) 877 { 878 struct ieee80211_node *ni; 879 880 IEEE80211_NODE_LOCK(ic); 881 TAILQ_FOREACH(ni, &ic->ic_node, ni_list) 882 (*f)(arg, ni); 883 IEEE80211_NODE_UNLOCK(ic); 884 } 885 886 void 887 ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp) 888 { 889 int newassoc; 890 891 if (ni->ni_associd == 0) { 892 u_int16_t aid; 893 894 /* 895 * It would be clever to search the bitmap 896 * more efficiently, but this will do for now. 897 */ 898 for (aid = 1; aid < ic->ic_max_aid; aid++) { 899 if (!IEEE80211_AID_ISSET(aid, 900 ic->ic_aid_bitmap)) 901 break; 902 } 903 if (aid >= ic->ic_max_aid) { 904 IEEE80211_SEND_MGMT(ic, ni, resp, 905 IEEE80211_REASON_ASSOC_TOOMANY); 906 ieee80211_node_leave(ic, ni); 907 return; 908 } 909 ni->ni_associd = aid | 0xc000; 910 IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap); 911 newassoc = 1; 912 /* XXX for 11g must turn off short slot time if long 913 slot time sta associates */ 914 } else 915 newassoc = 0; 916 917 IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG, 918 ("station %s %s associated at aid %d\n", 919 ether_sprintf(ni->ni_macaddr), 920 (newassoc ? "newly" : "already"), 921 ni->ni_associd & ~0xc000)); 922 923 /* give driver a chance to setup state like ni_txrate */ 924 if (ic->ic_newassoc) 925 (*ic->ic_newassoc)(ic, ni, newassoc); 926 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); 927 } 928 929 /* 930 * Handle bookkeeping for station deauthentication/disassociation 931 * when operating as an ap. 932 */ 933 void 934 ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni) 935 { 936 937 IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP, 938 ("not in ap mode, mode %u", ic->ic_opmode)); 939 /* 940 * If node wasn't previously associated all 941 * we need to do is reclaim the reference. 942 */ 943 if (ni->ni_associd == 0) 944 goto done; 945 IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); 946 ni->ni_associd = 0; 947 948 done: 949 ieee80211_free_node(ic, ni); 950 } 951
Indexes created Mon Sep 22 21:09:42 GMT 2025