ieee80211_input.c revision 127762
1/*- 2 * Copyright (c) 2001 Atsushi Onoe 3 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * Alternatively, this software may be distributed under the terms of the 18 * GNU General Public License ("GPL") version 2 as published by the Free 19 * Software Foundation. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33#include <sys/cdefs.h> 34__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_input.c 127762 2004-04-02 22:47:11Z sam $"); 35 36#include "opt_inet.h" 37 38#include <sys/param.h> 39#include <sys/systm.h> 40#include <sys/mbuf.h> 41#include <sys/malloc.h> 42#include <sys/kernel.h> 43#include <sys/socket.h> 44#include <sys/sockio.h> 45#include <sys/endian.h> 46#include <sys/errno.h> 47#include <sys/bus.h> 48#include <sys/proc.h> 49#include <sys/sysctl.h> 50 51#include <machine/atomic.h> 52 53#include <net/if.h> 54#include <net/if_dl.h> 55#include <net/if_media.h> 56#include <net/if_arp.h> 57#include <net/ethernet.h> 58#include <net/if_llc.h> 59 60#include <net80211/ieee80211_var.h> 61 62#include <net/bpf.h> 63 64#ifdef INET 65#include <netinet/in.h> 66#include <netinet/if_ether.h> 67#endif 68 69/* 70 * Process a received frame. The node associated with the sender 71 * should be supplied. If nothing was found in the node table then 72 * the caller is assumed to supply a reference to ic_bss instead. 73 * The RSSI and a timestamp are also supplied. The RSSI data is used 74 * during AP scanning to select a AP to associate with; it can have 75 * any units so long as values have consistent units and higher values 76 * mean ``better signal''. The receive timestamp is currently not used 77 * by the 802.11 layer. 78 */ 79void 80ieee80211_input(struct ifnet *ifp, struct mbuf *m, struct ieee80211_node *ni, 81 int rssi, u_int32_t rstamp) 82{ 83 struct ieee80211com *ic = (void *)ifp; 84 struct ieee80211_frame *wh; 85 struct ether_header *eh; 86 struct mbuf *m1; 87 int len; 88 u_int8_t dir, type, subtype; 89 u_int8_t *bssid; 90 u_int16_t rxseq; 91 92 KASSERT(ni != NULL, ("null node")); 93 94 /* trim CRC here so WEP can find its own CRC at the end of packet. */ 95 if (m->m_flags & M_HASFCS) { 96 m_adj(m, -IEEE80211_CRC_LEN); 97 m->m_flags &= ~M_HASFCS; 98 } 99 KASSERT(m->m_pkthdr.len >= sizeof(struct ieee80211_frame_min), 100 ("frame length too short: %u", m->m_pkthdr.len)); 101 102 /* 103 * In monitor mode, send everything directly to bpf. 104 * XXX may want to include the CRC 105 */ 106 if (ic->ic_opmode == IEEE80211_M_MONITOR) 107 goto out; 108 109 wh = mtod(m, struct ieee80211_frame *); 110 if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) != 111 IEEE80211_FC0_VERSION_0) { 112 if (ifp->if_flags & IFF_DEBUG) 113 if_printf(ifp, "receive packet with wrong version: %x\n", 114 wh->i_fc[0]); 115 ic->ic_stats.is_rx_badversion++; 116 goto err; 117 } 118 119 dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK; 120 type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK; 121 /* 122 * NB: We are not yet prepared to handle control frames, 123 * but permitting drivers to send them to us allows 124 * them to go through bpf tapping at the 802.11 layer. 125 */ 126 if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) { 127 /* XXX statistic */ 128 IEEE80211_DPRINTF2(("%s: frame too short, len %u\n", 129 __func__, m->m_pkthdr.len)); 130 ic->ic_stats.is_rx_tooshort++; 131 goto out; /* XXX */ 132 } 133 if (ic->ic_state != IEEE80211_S_SCAN) { 134 switch (ic->ic_opmode) { 135 case IEEE80211_M_STA: 136 if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_bssid)) { 137 /* not interested in */ 138 IEEE80211_DPRINTF2(("%s: discard frame from " 139 "bss %s\n", __func__, 140 ether_sprintf(wh->i_addr2))); 141 ic->ic_stats.is_rx_wrongbss++; 142 goto out; 143 } 144 break; 145 case IEEE80211_M_IBSS: 146 case IEEE80211_M_AHDEMO: 147 case IEEE80211_M_HOSTAP: 148 if (dir == IEEE80211_FC1_DIR_NODS) 149 bssid = wh->i_addr3; 150 else 151 bssid = wh->i_addr1; 152 if (!IEEE80211_ADDR_EQ(bssid, ic->ic_bss->ni_bssid) && 153 !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) { 154 /* not interested in */ 155 IEEE80211_DPRINTF2(("%s: discard frame from " 156 "bss %s\n", __func__, 157 ether_sprintf(bssid))); 158 ic->ic_stats.is_rx_wrongbss++; 159 goto out; 160 } 161 break; 162 case IEEE80211_M_MONITOR: 163 goto out; 164 default: 165 /* XXX catch bad values */ 166 break; 167 } 168 ni->ni_rssi = rssi; 169 ni->ni_rstamp = rstamp; 170 rxseq = ni->ni_rxseq; 171 ni->ni_rxseq = 172 le16toh(*(u_int16_t *)wh->i_seq) >> IEEE80211_SEQ_SEQ_SHIFT; 173 /* TODO: fragment */ 174 if ((wh->i_fc[1] & IEEE80211_FC1_RETRY) && 175 rxseq == ni->ni_rxseq) { 176 /* duplicate, silently discarded */ 177 ic->ic_stats.is_rx_dup++; /* XXX per-station stat */ 178 goto out; 179 } 180 ni->ni_inact = 0; 181 } 182 183 switch (type) { 184 case IEEE80211_FC0_TYPE_DATA: 185 switch (ic->ic_opmode) { 186 case IEEE80211_M_STA: 187 if (dir != IEEE80211_FC1_DIR_FROMDS) { 188 ic->ic_stats.is_rx_wrongdir++; 189 goto out; 190 } 191 if ((ifp->if_flags & IFF_SIMPLEX) && 192 IEEE80211_IS_MULTICAST(wh->i_addr1) && 193 IEEE80211_ADDR_EQ(wh->i_addr3, ic->ic_myaddr)) { 194 /* 195 * In IEEE802.11 network, multicast packet 196 * sent from me is broadcasted from AP. 197 * It should be silently discarded for 198 * SIMPLEX interface. 199 */ 200 ic->ic_stats.is_rx_mcastecho++; 201 goto out; 202 } 203 break; 204 case IEEE80211_M_IBSS: 205 case IEEE80211_M_AHDEMO: 206 if (dir != IEEE80211_FC1_DIR_NODS) { 207 ic->ic_stats.is_rx_wrongdir++; 208 goto out; 209 } 210 break; 211 case IEEE80211_M_HOSTAP: 212 if (dir != IEEE80211_FC1_DIR_TODS) { 213 ic->ic_stats.is_rx_wrongdir++; 214 goto out; 215 } 216 /* check if source STA is associated */ 217 if (ni == ic->ic_bss) { 218 IEEE80211_DPRINTF(("%s: data from unknown src " 219 "%s\n", __func__, 220 ether_sprintf(wh->i_addr2))); 221 /* NB: caller deals with reference */ 222 ni = ieee80211_dup_bss(ic, wh->i_addr2); 223 if (ni != NULL) { 224 IEEE80211_SEND_MGMT(ic, ni, 225 IEEE80211_FC0_SUBTYPE_DEAUTH, 226 IEEE80211_REASON_NOT_AUTHED); 227 ieee80211_free_node(ic, ni); 228 } 229 ic->ic_stats.is_rx_notassoc++; 230 goto err; 231 } 232 if (ni->ni_associd == 0) { 233 IEEE80211_DPRINTF(("ieee80211_input: " 234 "data from unassoc src %s\n", 235 ether_sprintf(wh->i_addr2))); 236 IEEE80211_SEND_MGMT(ic, ni, 237 IEEE80211_FC0_SUBTYPE_DISASSOC, 238 IEEE80211_REASON_NOT_ASSOCED); 239 ieee80211_unref_node(&ni); 240 ic->ic_stats.is_rx_notassoc++; 241 goto err; 242 } 243 break; 244 case IEEE80211_M_MONITOR: 245 break; 246 } 247 if (wh->i_fc[1] & IEEE80211_FC1_WEP) { 248 if (ic->ic_flags & IEEE80211_F_WEPON) { 249 m = ieee80211_wep_crypt(ifp, m, 0); 250 if (m == NULL) { 251 ic->ic_stats.is_rx_wepfail++; 252 goto err; 253 } 254 wh = mtod(m, struct ieee80211_frame *); 255 } else { 256 ic->ic_stats.is_rx_nowep++; 257 goto out; 258 } 259 } 260 /* copy to listener after decrypt */ 261 if (ic->ic_rawbpf) 262 bpf_mtap(ic->ic_rawbpf, m); 263 m = ieee80211_decap(ifp, m); 264 if (m == NULL) { 265 ic->ic_stats.is_rx_decap++; 266 goto err; 267 } 268 ifp->if_ipackets++; 269 270 /* perform as a bridge within the AP */ 271 m1 = NULL; 272 if (ic->ic_opmode == IEEE80211_M_HOSTAP) { 273 eh = mtod(m, struct ether_header *); 274 if (ETHER_IS_MULTICAST(eh->ether_dhost)) { 275 m1 = m_copypacket(m, M_DONTWAIT); 276 if (m1 == NULL) 277 ifp->if_oerrors++; 278 else 279 m1->m_flags |= M_MCAST; 280 } else { 281 ni = ieee80211_find_node(ic, eh->ether_dhost); 282 if (ni != NULL) { 283 if (ni->ni_associd != 0) { 284 m1 = m; 285 m = NULL; 286 } 287 ieee80211_unref_node(&ni); 288 } 289 } 290 if (m1 != NULL) { 291#ifdef ALTQ 292 if (ALTQ_IS_ENABLED(&ifp->if_snd)) 293 altq_etherclassify(&ifp->if_snd, m1, 294 &pktattr); 295#endif 296 len = m1->m_pkthdr.len; 297 IF_ENQUEUE(&ifp->if_snd, m1); 298 if (m != NULL) 299 ifp->if_omcasts++; 300 ifp->if_obytes += len; 301 } 302 } 303 if (m != NULL) 304 (*ifp->if_input)(ifp, m); 305 return; 306 307 case IEEE80211_FC0_TYPE_MGT: 308 if (dir != IEEE80211_FC1_DIR_NODS) { 309 ic->ic_stats.is_rx_wrongdir++; 310 goto err; 311 } 312 if (ic->ic_opmode == IEEE80211_M_AHDEMO) { 313 ic->ic_stats.is_rx_ahdemo_mgt++; 314 goto out; 315 } 316 subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK; 317 318 /* drop frames without interest */ 319 if (ic->ic_state == IEEE80211_S_SCAN) { 320 if (subtype != IEEE80211_FC0_SUBTYPE_BEACON && 321 subtype != IEEE80211_FC0_SUBTYPE_PROBE_RESP) { 322 ic->ic_stats.is_rx_mgtdiscard++; 323 goto out; 324 } 325 } else { 326 if (ic->ic_opmode != IEEE80211_M_IBSS && 327 subtype == IEEE80211_FC0_SUBTYPE_BEACON) { 328 ic->ic_stats.is_rx_mgtdiscard++; 329 goto out; 330 } 331 } 332 333 if (ifp->if_flags & IFF_DEBUG) { 334 /* avoid to print too many frames */ 335 int doprint = 0; 336 337 switch (subtype) { 338 case IEEE80211_FC0_SUBTYPE_BEACON: 339 if (ic->ic_state == IEEE80211_S_SCAN) 340 doprint = 1; 341 break; 342 case IEEE80211_FC0_SUBTYPE_PROBE_REQ: 343 if (ic->ic_opmode == IEEE80211_M_IBSS) 344 doprint = 1; 345 break; 346 default: 347 doprint = 1; 348 break; 349 } 350#ifdef IEEE80211_DEBUG 351 doprint += ieee80211_debug; 352#endif 353 if (doprint) 354 if_printf(ifp, "received %s from %s rssi %d\n", 355 ieee80211_mgt_subtype_name[subtype 356 >> IEEE80211_FC0_SUBTYPE_SHIFT], 357 ether_sprintf(wh->i_addr2), rssi); 358 } 359 if (ic->ic_rawbpf) 360 bpf_mtap(ic->ic_rawbpf, m); 361 (*ic->ic_recv_mgmt)(ic, m, ni, subtype, rssi, rstamp); 362 m_freem(m); 363 return; 364 365 case IEEE80211_FC0_TYPE_CTL: 366 ic->ic_stats.is_rx_ctl++; 367 goto out; 368 default: 369 IEEE80211_DPRINTF(("%s: bad type %x\n", __func__, type)); 370 /* should not come here */ 371 break; 372 } 373 err: 374 ifp->if_ierrors++; 375 out: 376 if (m != NULL) { 377 if (ic->ic_rawbpf) 378 bpf_mtap(ic->ic_rawbpf, m); 379 m_freem(m); 380 } 381} 382 383struct mbuf * 384ieee80211_decap(struct ifnet *ifp, struct mbuf *m) 385{ 386 struct ether_header *eh; 387 struct ieee80211_frame wh; 388 struct llc *llc; 389 390 if (m->m_len < sizeof(wh) + sizeof(*llc)) { 391 m = m_pullup(m, sizeof(wh) + sizeof(*llc)); 392 if (m == NULL) 393 return NULL; 394 } 395 memcpy(&wh, mtod(m, caddr_t), sizeof(wh)); 396 llc = (struct llc *)(mtod(m, caddr_t) + sizeof(wh)); 397 if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP && 398 llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 && 399 llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0) { 400 m_adj(m, sizeof(wh) + sizeof(struct llc) - sizeof(*eh)); 401 llc = NULL; 402 } else { 403 m_adj(m, sizeof(wh) - sizeof(*eh)); 404 } 405 eh = mtod(m, struct ether_header *); 406 switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) { 407 case IEEE80211_FC1_DIR_NODS: 408 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1); 409 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2); 410 break; 411 case IEEE80211_FC1_DIR_TODS: 412 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3); 413 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2); 414 break; 415 case IEEE80211_FC1_DIR_FROMDS: 416 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1); 417 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3); 418 break; 419 case IEEE80211_FC1_DIR_DSTODS: 420 /* not yet supported */ 421 IEEE80211_DPRINTF(("%s: DS to DS\n", __func__)); 422 m_freem(m); 423 return NULL; 424 } 425#ifdef ALIGNED_POINTER 426 if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), u_int32_t)) { 427 struct mbuf *n, *n0, **np; 428 caddr_t newdata; 429 int off, pktlen; 430 431 n0 = NULL; 432 np = &n0; 433 off = 0; 434 pktlen = m->m_pkthdr.len; 435 while (pktlen > off) { 436 if (n0 == NULL) { 437 MGETHDR(n, M_DONTWAIT, MT_DATA); 438 if (n == NULL) { 439 m_freem(m); 440 return NULL; 441 } 442 M_MOVE_PKTHDR(n, m); 443 n->m_len = MHLEN; 444 } else { 445 MGET(n, M_DONTWAIT, MT_DATA); 446 if (n == NULL) { 447 m_freem(m); 448 m_freem(n0); 449 return NULL; 450 } 451 n->m_len = MLEN; 452 } 453 if (pktlen - off >= MINCLSIZE) { 454 MCLGET(n, M_DONTWAIT); 455 if (n->m_flags & M_EXT) 456 n->m_len = n->m_ext.ext_size; 457 } 458 if (n0 == NULL) { 459 newdata = 460 (caddr_t)ALIGN(n->m_data + sizeof(*eh)) - 461 sizeof(*eh); 462 n->m_len -= newdata - n->m_data; 463 n->m_data = newdata; 464 } 465 if (n->m_len > pktlen - off) 466 n->m_len = pktlen - off; 467 m_copydata(m, off, n->m_len, mtod(n, caddr_t)); 468 off += n->m_len; 469 *np = n; 470 np = &n->m_next; 471 } 472 m_freem(m); 473 m = n0; 474 } 475#endif /* ALIGNED_POINTER */ 476 if (llc != NULL) { 477 eh = mtod(m, struct ether_header *); 478 eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh)); 479 } 480 return m; 481} 482 483/* 484 * Install received rate set information in the node's state block. 485 */ 486static int 487ieee80211_setup_rates(struct ieee80211com *ic, struct ieee80211_node *ni, 488 u_int8_t *rates, u_int8_t *xrates, int flags) 489{ 490 struct ieee80211_rateset *rs = &ni->ni_rates; 491 492 memset(rs, 0, sizeof(*rs)); 493 rs->rs_nrates = rates[1]; 494 memcpy(rs->rs_rates, rates + 2, rs->rs_nrates); 495 if (xrates != NULL) { 496 u_int8_t nxrates; 497 /* 498 * Tack on 11g extended supported rate element. 499 */ 500 nxrates = xrates[1]; 501 if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) { 502 nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates; 503 IEEE80211_DPRINTF(("%s: extended rate set too large;" 504 " only using %u of %u rates\n", 505 __func__, nxrates, xrates[1])); 506 ic->ic_stats.is_rx_rstoobig++; 507 } 508 memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates); 509 rs->rs_nrates += nxrates; 510 } 511 return ieee80211_fix_rate(ic, ni, flags); 512} 513 514/* Verify the existence and length of __elem or get out. */ 515#define IEEE80211_VERIFY_ELEMENT(__elem, __maxlen) do { \ 516 if ((__elem) == NULL) { \ 517 IEEE80211_DPRINTF(("%s: no " #__elem "in %s frame\n", \ 518 __func__, ieee80211_mgt_subtype_name[subtype >> \ 519 IEEE80211_FC0_SUBTYPE_SHIFT])); \ 520 ic->ic_stats.is_rx_elem_missing++; \ 521 return; \ 522 } \ 523 if ((__elem)[1] > (__maxlen)) { \ 524 IEEE80211_DPRINTF(("%s: bad " #__elem " len %d in %s " \ 525 "frame from %s\n", __func__, (__elem)[1], \ 526 ieee80211_mgt_subtype_name[subtype >> \ 527 IEEE80211_FC0_SUBTYPE_SHIFT], \ 528 ether_sprintf(wh->i_addr2))); \ 529 ic->ic_stats.is_rx_elem_toobig++; \ 530 return; \ 531 } \ 532} while (0) 533 534#define IEEE80211_VERIFY_LENGTH(_len, _minlen) do { \ 535 if ((_len) < (_minlen)) { \ 536 IEEE80211_DPRINTF(("%s: %s frame too short from %s\n", \ 537 __func__, \ 538 ieee80211_mgt_subtype_name[subtype >> \ 539 IEEE80211_FC0_SUBTYPE_SHIFT], \ 540 ether_sprintf(wh->i_addr2))); \ 541 ic->ic_stats.is_rx_elem_toosmall++; \ 542 return; \ 543 } \ 544} while (0) 545 546void 547ieee80211_recv_mgmt(struct ieee80211com *ic, struct mbuf *m0, 548 struct ieee80211_node *ni, 549 int subtype, int rssi, u_int32_t rstamp) 550{ 551#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 552 struct ifnet *ifp = &ic->ic_if; 553 struct ieee80211_frame *wh; 554 u_int8_t *frm, *efrm; 555 u_int8_t *ssid, *rates, *xrates; 556 int reassoc, resp, newassoc, allocbs; 557 558 wh = mtod(m0, struct ieee80211_frame *); 559 frm = (u_int8_t *)&wh[1]; 560 efrm = mtod(m0, u_int8_t *) + m0->m_len; 561 switch (subtype) { 562 case IEEE80211_FC0_SUBTYPE_PROBE_RESP: 563 case IEEE80211_FC0_SUBTYPE_BEACON: { 564 u_int8_t *tstamp, *bintval, *capinfo, *country; 565 u_int8_t chan, bchan, fhindex, erp; 566 u_int16_t fhdwell; 567 568 if (ic->ic_opmode != IEEE80211_M_IBSS && 569 ic->ic_state != IEEE80211_S_SCAN) { 570 /* XXX: may be useful for background scan */ 571 return; 572 } 573 574 /* 575 * beacon/probe response frame format 576 * [8] time stamp 577 * [2] beacon interval 578 * [2] capability information 579 * [tlv] ssid 580 * [tlv] supported rates 581 * [tlv] country information 582 * [tlv] parameter set (FH/DS) 583 * [tlv] erp information 584 * [tlv] extended supported rates 585 */ 586 IEEE80211_VERIFY_LENGTH(efrm - frm, 12); 587 tstamp = frm; frm += 8; 588 bintval = frm; frm += 2; 589 capinfo = frm; frm += 2; 590 ssid = rates = xrates = country = NULL; 591 bchan = ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan); 592 chan = bchan; 593 fhdwell = 0; 594 fhindex = 0; 595 erp = 0; 596 while (frm < efrm) { 597 switch (*frm) { 598 case IEEE80211_ELEMID_SSID: 599 ssid = frm; 600 break; 601 case IEEE80211_ELEMID_RATES: 602 rates = frm; 603 break; 604 case IEEE80211_ELEMID_COUNTRY: 605 country = frm; 606 break; 607 case IEEE80211_ELEMID_FHPARMS: 608 if (ic->ic_phytype == IEEE80211_T_FH) { 609 fhdwell = (frm[3] << 8) | frm[2]; 610 chan = IEEE80211_FH_CHAN(frm[4], frm[5]); 611 fhindex = frm[6]; 612 } 613 break; 614 case IEEE80211_ELEMID_DSPARMS: 615 /* 616 * XXX hack this since depending on phytype 617 * is problematic for multi-mode devices. 618 */ 619 if (ic->ic_phytype != IEEE80211_T_FH) 620 chan = frm[2]; 621 break; 622 case IEEE80211_ELEMID_TIM: 623 break; 624 case IEEE80211_ELEMID_XRATES: 625 xrates = frm; 626 break; 627 case IEEE80211_ELEMID_ERP: 628 if (frm[1] != 1) { 629 IEEE80211_DPRINTF(("%s: invalid ERP " 630 "element; length %u, expecting " 631 "1\n", __func__, frm[1])); 632 ic->ic_stats.is_rx_elem_toobig++; 633 break; 634 } 635 erp = frm[2]; 636 break; 637 default: 638 IEEE80211_DPRINTF2(("%s: element id %u/len %u " 639 "ignored\n", __func__, *frm, frm[1])); 640 ic->ic_stats.is_rx_elem_unknown++; 641 break; 642 } 643 frm += frm[1] + 2; 644 } 645 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); 646 IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN); 647 if ( 648#if IEEE80211_CHAN_MAX < 255 649 chan > IEEE80211_CHAN_MAX || 650#endif 651 isclr(ic->ic_chan_active, chan)) { 652 IEEE80211_DPRINTF(("%s: ignore %s with invalid channel " 653 "%u\n", __func__, 654 ISPROBE(subtype) ? "probe response" : "beacon", 655 chan)); 656 ic->ic_stats.is_rx_badchan++; 657 return; 658 } 659 if (chan != bchan && ic->ic_phytype != IEEE80211_T_FH) { 660 /* 661 * Frame was received on a channel different from the 662 * one indicated in the DS params element id; 663 * silently discard it. 664 * 665 * NB: this can happen due to signal leakage. 666 * But we should take it for FH phy because 667 * the rssi value should be correct even for 668 * different hop pattern in FH. 669 */ 670 IEEE80211_DPRINTF(("%s: ignore %s on channel %u marked " 671 "for channel %u\n", __func__, 672 ISPROBE(subtype) ? "probe response" : "beacon", 673 bchan, chan)); 674 ic->ic_stats.is_rx_chanmismatch++; 675 return; 676 } 677 678 /* 679 * Use mac and channel for lookup so we collect all 680 * potential AP's when scanning. Otherwise we may 681 * see the same AP on multiple channels and will only 682 * record the last one. We could filter APs here based 683 * on rssi, etc. but leave that to the end of the scan 684 * so we can keep the selection criteria in one spot. 685 * This may result in a bloat of the scanned AP list but 686 * it shouldn't be too much. 687 */ 688 ni = ieee80211_lookup_node(ic, wh->i_addr2, 689 &ic->ic_channels[chan]); 690#ifdef IEEE80211_DEBUG 691 if (ieee80211_debug && 692 (ni == NULL || ic->ic_state == IEEE80211_S_SCAN)) { 693 printf("%s: %s%s on chan %u (bss chan %u) ", 694 __func__, (ni == NULL ? "new " : ""), 695 ISPROBE(subtype) ? "probe response" : "beacon", 696 chan, bchan); 697 ieee80211_print_essid(ssid + 2, ssid[1]); 698 printf(" from %s\n", ether_sprintf(wh->i_addr2)); 699 printf("%s: caps 0x%x bintval %u erp 0x%x\n", 700 __func__, le16toh(*(u_int16_t *)capinfo), 701 le16toh(*(u_int16_t *)bintval), erp); 702 if (country) 703 printf("%s: country info %*D\n", 704 __func__, country[1], country+2, " "); 705 } 706#endif 707 if (ni == NULL) { 708 ni = ieee80211_alloc_node(ic, wh->i_addr2); 709 if (ni == NULL) { 710 ic->ic_stats.is_rx_nodealloc++; 711 return; 712 } 713 ni->ni_esslen = ssid[1]; 714 memset(ni->ni_essid, 0, sizeof(ni->ni_essid)); 715 memcpy(ni->ni_essid, ssid + 2, ssid[1]); 716 } else if (ssid[1] != 0 && ISPROBE(subtype)) { 717 /* 718 * Update ESSID at probe response to adopt hidden AP by 719 * Lucent/Cisco, which announces null ESSID in beacon. 720 */ 721 ni->ni_esslen = ssid[1]; 722 memset(ni->ni_essid, 0, sizeof(ni->ni_essid)); 723 memcpy(ni->ni_essid, ssid + 2, ssid[1]); 724 } 725 IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3); 726 ni->ni_rssi = rssi; 727 ni->ni_rstamp = rstamp; 728 memcpy(ni->ni_tstamp, tstamp, sizeof(ni->ni_tstamp)); 729 ni->ni_intval = le16toh(*(u_int16_t *)bintval); 730 ni->ni_capinfo = le16toh(*(u_int16_t *)capinfo); 731 /* XXX validate channel # */ 732 ni->ni_chan = &ic->ic_channels[chan]; 733 ni->ni_fhdwell = fhdwell; 734 ni->ni_fhindex = fhindex; 735 ni->ni_erp = erp; 736 /* NB: must be after ni_chan is setup */ 737 ieee80211_setup_rates(ic, ni, rates, xrates, IEEE80211_F_DOSORT); 738 ieee80211_unref_node(&ni); 739 break; 740 } 741 742 case IEEE80211_FC0_SUBTYPE_PROBE_REQ: { 743 u_int8_t rate; 744 745 if (ic->ic_opmode == IEEE80211_M_STA) 746 return; 747 if (ic->ic_state != IEEE80211_S_RUN) 748 return; 749 750 /* 751 * prreq frame format 752 * [tlv] ssid 753 * [tlv] supported rates 754 * [tlv] extended supported rates 755 */ 756 ssid = rates = xrates = NULL; 757 while (frm < efrm) { 758 switch (*frm) { 759 case IEEE80211_ELEMID_SSID: 760 ssid = frm; 761 break; 762 case IEEE80211_ELEMID_RATES: 763 rates = frm; 764 break; 765 case IEEE80211_ELEMID_XRATES: 766 xrates = frm; 767 break; 768 } 769 frm += frm[1] + 2; 770 } 771 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); 772 IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN); 773 if (ssid[1] != 0 && 774 (ssid[1] != ic->ic_bss->ni_esslen || 775 memcmp(ssid + 2, ic->ic_bss->ni_essid, ic->ic_bss->ni_esslen) != 0)) { 776#ifdef IEEE80211_DEBUG 777 if (ieee80211_debug) { 778 printf("%s: ssid unmatch ", __func__); 779 ieee80211_print_essid(ssid + 2, ssid[1]); 780 printf(" from %s\n", ether_sprintf(wh->i_addr2)); 781 } 782#endif 783 ic->ic_stats.is_rx_ssidmismatch++; 784 return; 785 } 786 787 if (ni == ic->ic_bss) { 788 ni = ieee80211_dup_bss(ic, wh->i_addr2); 789 if (ni == NULL) { 790 ic->ic_stats.is_rx_nodealloc++; 791 return; 792 } 793 IEEE80211_DPRINTF(("%s: new req from %s\n", 794 __func__, ether_sprintf(wh->i_addr2))); 795 allocbs = 1; 796 } else 797 allocbs = 0; 798 ni->ni_rssi = rssi; 799 ni->ni_rstamp = rstamp; 800 rate = ieee80211_setup_rates(ic, ni, rates, xrates, 801 IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE 802 | IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 803 if (rate & IEEE80211_RATE_BASIC) { 804 IEEE80211_DPRINTF(("%s: rate negotiation failed: %s\n", 805 __func__,ether_sprintf(wh->i_addr2))); 806 } else { 807 IEEE80211_SEND_MGMT(ic, ni, 808 IEEE80211_FC0_SUBTYPE_PROBE_RESP, 0); 809 } 810 if (allocbs) { 811 /* XXX just use free? */ 812 if (ic->ic_opmode == IEEE80211_M_HOSTAP) 813 ieee80211_free_node(ic, ni); 814 else 815 ieee80211_unref_node(&ni); 816 } 817 break; 818 } 819 820 case IEEE80211_FC0_SUBTYPE_AUTH: { 821 u_int16_t algo, seq, status; 822 /* 823 * auth frame format 824 * [2] algorithm 825 * [2] sequence 826 * [2] status 827 * [tlv*] challenge 828 */ 829 IEEE80211_VERIFY_LENGTH(efrm - frm, 6); 830 algo = le16toh(*(u_int16_t *)frm); 831 seq = le16toh(*(u_int16_t *)(frm + 2)); 832 status = le16toh(*(u_int16_t *)(frm + 4)); 833 if (algo != IEEE80211_AUTH_ALG_OPEN) { 834 /* TODO: shared key auth */ 835 IEEE80211_DPRINTF(("%s: unsupported auth %d from %s\n", 836 __func__, algo, ether_sprintf(wh->i_addr2))); 837 ic->ic_stats.is_rx_auth_unsupported++; 838 return; 839 } 840 switch (ic->ic_opmode) { 841 case IEEE80211_M_IBSS: 842 if (ic->ic_state != IEEE80211_S_RUN || seq != 1) { 843 IEEE80211_DPRINTF(("%s: discard auth from %s; " 844 "state %u, seq %u\n", __func__, 845 ether_sprintf(wh->i_addr2), 846 ic->ic_state, seq)); 847 ic->ic_stats.is_rx_bad_auth++; 848 break; 849 } 850 ieee80211_new_state(ic, IEEE80211_S_AUTH, 851 wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); 852 break; 853 854 case IEEE80211_M_AHDEMO: 855 /* should not come here */ 856 break; 857 858 case IEEE80211_M_HOSTAP: 859 if (ic->ic_state != IEEE80211_S_RUN || seq != 1) { 860 IEEE80211_DPRINTF(("%s: discard auth from %s; " 861 "state %u, seq %u\n", __func__, 862 ether_sprintf(wh->i_addr2), 863 ic->ic_state, seq)); 864 ic->ic_stats.is_rx_bad_auth++; 865 break; 866 } 867 if (ni == ic->ic_bss) { 868 ni = ieee80211_alloc_node(ic, wh->i_addr2); 869 if (ni == NULL) { 870 ic->ic_stats.is_rx_nodealloc++; 871 return; 872 } 873 IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); 874 ni->ni_rssi = rssi; 875 ni->ni_rstamp = rstamp; 876 ni->ni_chan = ic->ic_bss->ni_chan; 877 allocbs = 1; 878 } else 879 allocbs = 0; 880 IEEE80211_SEND_MGMT(ic, ni, 881 IEEE80211_FC0_SUBTYPE_AUTH, 2); 882 if (ifp->if_flags & IFF_DEBUG) 883 if_printf(ifp, "station %s %s authenticated\n", 884 (allocbs ? "newly" : "already"), 885 ether_sprintf(ni->ni_macaddr)); 886 break; 887 888 case IEEE80211_M_STA: 889 if (ic->ic_state != IEEE80211_S_AUTH || seq != 2) { 890 IEEE80211_DPRINTF(("%s: discard auth from %s; " 891 "state %u, seq %u\n", __func__, 892 ether_sprintf(wh->i_addr2), 893 ic->ic_state, seq)); 894 ic->ic_stats.is_rx_bad_auth++; 895 break; 896 } 897 if (status != 0) { 898 if_printf(&ic->ic_if, 899 "authentication failed (reason %d) for %s\n", 900 status, 901 ether_sprintf(wh->i_addr3)); 902 if (ni != ic->ic_bss) 903 ni->ni_fails++; 904 ic->ic_stats.is_rx_auth_fail++; 905 return; 906 } 907 ieee80211_new_state(ic, IEEE80211_S_ASSOC, 908 wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); 909 break; 910 case IEEE80211_M_MONITOR: 911 break; 912 } 913 break; 914 } 915 916 case IEEE80211_FC0_SUBTYPE_ASSOC_REQ: 917 case IEEE80211_FC0_SUBTYPE_REASSOC_REQ: { 918 u_int16_t capinfo, bintval; 919 920 if (ic->ic_opmode != IEEE80211_M_HOSTAP || 921 (ic->ic_state != IEEE80211_S_RUN)) 922 return; 923 924 if (subtype == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) { 925 reassoc = 1; 926 resp = IEEE80211_FC0_SUBTYPE_REASSOC_RESP; 927 } else { 928 reassoc = 0; 929 resp = IEEE80211_FC0_SUBTYPE_ASSOC_RESP; 930 } 931 /* 932 * asreq frame format 933 * [2] capability information 934 * [2] listen interval 935 * [6*] current AP address (reassoc only) 936 * [tlv] ssid 937 * [tlv] supported rates 938 * [tlv] extended supported rates 939 */ 940 IEEE80211_VERIFY_LENGTH(efrm - frm, (reassoc ? 10 : 4)); 941 if (!IEEE80211_ADDR_EQ(wh->i_addr3, ic->ic_bss->ni_bssid)) { 942 IEEE80211_DPRINTF(("%s: ignore other bss from %s\n", 943 __func__, ether_sprintf(wh->i_addr2))); 944 ic->ic_stats.is_rx_assoc_bss++; 945 return; 946 } 947 capinfo = le16toh(*(u_int16_t *)frm); frm += 2; 948 bintval = le16toh(*(u_int16_t *)frm); frm += 2; 949 if (reassoc) 950 frm += 6; /* ignore current AP info */ 951 ssid = rates = xrates = NULL; 952 while (frm < efrm) { 953 switch (*frm) { 954 case IEEE80211_ELEMID_SSID: 955 ssid = frm; 956 break; 957 case IEEE80211_ELEMID_RATES: 958 rates = frm; 959 break; 960 case IEEE80211_ELEMID_XRATES: 961 xrates = frm; 962 break; 963 } 964 frm += frm[1] + 2; 965 } 966 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); 967 IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN); 968 if (ssid[1] != ic->ic_bss->ni_esslen || 969 memcmp(ssid + 2, ic->ic_bss->ni_essid, ssid[1]) != 0) { 970#ifdef IEEE80211_DEBUG 971 if (ieee80211_debug) { 972 printf("%s: ssid unmatch ", __func__); 973 ieee80211_print_essid(ssid + 2, ssid[1]); 974 printf(" from %s\n", ether_sprintf(wh->i_addr2)); 975 } 976#endif 977 ic->ic_stats.is_rx_ssidmismatch++; 978 return; 979 } 980 if (ni == ic->ic_bss) { 981 IEEE80211_DPRINTF(("%s: not authenticated for %s\n", 982 __func__, ether_sprintf(wh->i_addr2))); 983 ni = ieee80211_dup_bss(ic, wh->i_addr2); 984 if (ni != NULL) { 985 IEEE80211_SEND_MGMT(ic, ni, 986 IEEE80211_FC0_SUBTYPE_DEAUTH, 987 IEEE80211_REASON_ASSOC_NOT_AUTHED); 988 ieee80211_free_node(ic, ni); 989 } 990 ic->ic_stats.is_rx_assoc_notauth++; 991 return; 992 } 993 /* XXX per-node cipher suite */ 994 /* XXX some stations use the privacy bit for handling APs 995 that suport both encrypted and unencrypted traffic */ 996 if ((capinfo & IEEE80211_CAPINFO_ESS) == 0 || 997 (capinfo & IEEE80211_CAPINFO_PRIVACY) != 998 ((ic->ic_flags & IEEE80211_F_WEPON) ? 999 IEEE80211_CAPINFO_PRIVACY : 0)) { 1000 IEEE80211_DPRINTF(("%s: capability mismatch %x for %s\n", 1001 __func__, capinfo, ether_sprintf(wh->i_addr2))); 1002 ni->ni_associd = 0; 1003 IEEE80211_SEND_MGMT(ic, ni, resp, 1004 IEEE80211_STATUS_CAPINFO); 1005 ic->ic_stats.is_rx_assoc_capmismatch++; 1006 return; 1007 } 1008 ieee80211_setup_rates(ic, ni, rates, xrates, 1009 IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE | 1010 IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 1011 if (ni->ni_rates.rs_nrates == 0) { 1012 IEEE80211_DPRINTF(("%s: rate unmatch for %s\n", 1013 __func__, ether_sprintf(wh->i_addr2))); 1014 ni->ni_associd = 0; 1015 IEEE80211_SEND_MGMT(ic, ni, resp, 1016 IEEE80211_STATUS_BASIC_RATE); 1017 ic->ic_stats.is_rx_assoc_norate++; 1018 return; 1019 } 1020 ni->ni_rssi = rssi; 1021 ni->ni_rstamp = rstamp; 1022 ni->ni_intval = bintval; 1023 ni->ni_capinfo = capinfo; 1024 ni->ni_chan = ic->ic_bss->ni_chan; 1025 ni->ni_fhdwell = ic->ic_bss->ni_fhdwell; 1026 ni->ni_fhindex = ic->ic_bss->ni_fhindex; 1027 if (ni->ni_associd == 0) { 1028 /* XXX handle rollover at 2007 */ 1029 /* XXX guarantee uniqueness */ 1030 ni->ni_associd = 0xc000 | ic->ic_bss->ni_associd++; 1031 newassoc = 1; 1032 } else 1033 newassoc = 0; 1034 /* XXX for 11g must turn off short slot time if long 1035 slot time sta associates */ 1036 IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); 1037 if (ifp->if_flags & IFF_DEBUG) 1038 if_printf(ifp, "station %s %s associated\n", 1039 (newassoc ? "newly" : "already"), 1040 ether_sprintf(ni->ni_macaddr)); 1041 /* give driver a chance to setup state like ni_txrate */ 1042 if (ic->ic_newassoc) 1043 (*ic->ic_newassoc)(ic, ni, newassoc); 1044 break; 1045 } 1046 1047 case IEEE80211_FC0_SUBTYPE_ASSOC_RESP: 1048 case IEEE80211_FC0_SUBTYPE_REASSOC_RESP: { 1049 u_int16_t status; 1050 1051 if (ic->ic_opmode != IEEE80211_M_STA || 1052 ic->ic_state != IEEE80211_S_ASSOC) 1053 return; 1054 1055 /* 1056 * asresp frame format 1057 * [2] capability information 1058 * [2] status 1059 * [2] association ID 1060 * [tlv] supported rates 1061 * [tlv] extended supported rates 1062 */ 1063 IEEE80211_VERIFY_LENGTH(efrm - frm, 6); 1064 ni = ic->ic_bss; 1065 ni->ni_capinfo = le16toh(*(u_int16_t *)frm); 1066 frm += 2; 1067 1068 status = le16toh(*(u_int16_t *)frm); 1069 frm += 2; 1070 if (status != 0) { 1071 if_printf(ifp, "association failed (reason %d) for %s\n", 1072 status, ether_sprintf(wh->i_addr3)); 1073 if (ni != ic->ic_bss) 1074 ni->ni_fails++; 1075 ic->ic_stats.is_rx_auth_fail++; 1076 return; 1077 } 1078 ni->ni_associd = le16toh(*(u_int16_t *)frm); 1079 frm += 2; 1080 1081 rates = xrates = NULL; 1082 while (frm < efrm) { 1083 switch (*frm) { 1084 case IEEE80211_ELEMID_RATES: 1085 rates = frm; 1086 break; 1087 case IEEE80211_ELEMID_XRATES: 1088 xrates = frm; 1089 break; 1090 } 1091 frm += frm[1] + 2; 1092 } 1093 1094 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE); 1095 ieee80211_setup_rates(ic, ni, rates, xrates, 1096 IEEE80211_F_DOSORT | IEEE80211_F_DOFRATE | 1097 IEEE80211_F_DONEGO | IEEE80211_F_DODEL); 1098 if (ni->ni_rates.rs_nrates != 0) 1099 ieee80211_new_state(ic, IEEE80211_S_RUN, 1100 wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); 1101 break; 1102 } 1103 1104 case IEEE80211_FC0_SUBTYPE_DEAUTH: { 1105 u_int16_t reason; 1106 /* 1107 * deauth frame format 1108 * [2] reason 1109 */ 1110 IEEE80211_VERIFY_LENGTH(efrm - frm, 2); 1111 reason = le16toh(*(u_int16_t *)frm); 1112 ic->ic_stats.is_rx_deauth++; 1113 switch (ic->ic_opmode) { 1114 case IEEE80211_M_STA: 1115 ieee80211_new_state(ic, IEEE80211_S_AUTH, 1116 wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); 1117 break; 1118 case IEEE80211_M_HOSTAP: 1119 if (ni != ic->ic_bss) { 1120 if (ifp->if_flags & IFF_DEBUG) 1121 if_printf(ifp, "station %s deauthenticated" 1122 " by peer (reason %d)\n", 1123 ether_sprintf(ni->ni_macaddr), reason); 1124 /* node will be free'd on return */ 1125 ieee80211_unref_node(&ni); 1126 } 1127 break; 1128 default: 1129 break; 1130 } 1131 break; 1132 } 1133 1134 case IEEE80211_FC0_SUBTYPE_DISASSOC: { 1135 u_int16_t reason; 1136 /* 1137 * disassoc frame format 1138 * [2] reason 1139 */ 1140 IEEE80211_VERIFY_LENGTH(efrm - frm, 2); 1141 reason = le16toh(*(u_int16_t *)frm); 1142 ic->ic_stats.is_rx_disassoc++; 1143 switch (ic->ic_opmode) { 1144 case IEEE80211_M_STA: 1145 ieee80211_new_state(ic, IEEE80211_S_ASSOC, 1146 wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK); 1147 break; 1148 case IEEE80211_M_HOSTAP: 1149 if (ni != ic->ic_bss) { 1150 if (ifp->if_flags & IFF_DEBUG) 1151 if_printf(ifp, "station %s disassociated" 1152 " by peer (reason %d)\n", 1153 ether_sprintf(ni->ni_macaddr), reason); 1154 ni->ni_associd = 0; 1155 /* XXX node reclaimed how? */ 1156 } 1157 break; 1158 default: 1159 break; 1160 } 1161 break; 1162 } 1163 default: 1164 IEEE80211_DPRINTF(("%s: mgmt frame with subtype 0x%x not " 1165 "handled\n", __func__, subtype)); 1166 ic->ic_stats.is_rx_badsubtype++; 1167 break; 1168 } 1169#undef ISPROBE 1170} 1171#undef IEEE80211_VERIFY_LENGTH 1172#undef IEEE80211_VERIFY_ELEMENT 1173