sys/net80211/ieee80211_adhoc.c

   1 /*-
   2  * Copyright (c) 2007-2009 Sam Leffler, Errno Consulting
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #include <sys/cdefs.h>
  27 #ifdef __FreeBSD__
  28 __FBSDID("$FreeBSD$");
  29 #endif
  30
  31 /*
  32  * IEEE 802.11 IBSS mode support.
  33  */
  34 #include "opt_inet.h"
  35 #include "opt_wlan.h"
  36
  37 #include <sys/param.h>
  38 #include <sys/systm.h>
  39 #include <sys/mbuf.h>
  40 #include <sys/malloc.h>
  41 #include <sys/kernel.h>
  42
  43 #include <sys/socket.h>
  44 #include <sys/sockio.h>
  45 #include <sys/endian.h>
  46 #include <sys/errno.h>
  47 #include <sys/proc.h>
  48 #include <sys/sysctl.h>
  49
  50 #include <net/if.h>
  51 #include <net/if_var.h>
  52 #include <net/if_media.h>
  53 #include <net/if_llc.h>
  54 #include <net/ethernet.h>
  55
  56 #include <net/bpf.h>
  57
  58 #include <net80211/ieee80211_var.h>
  59 #include <net80211/ieee80211_adhoc.h>
  60 #include <net80211/ieee80211_input.h>
  61 #ifdef IEEE80211_SUPPORT_SUPERG
  62 #include <net80211/ieee80211_superg.h>
  63 #endif
  64 #ifdef IEEE80211_SUPPORT_TDMA
  65 #include <net80211/ieee80211_tdma.h>
  66 #endif
  67 #include <net80211/ieee80211_sta.h>
  68
  69 #define IEEE80211_RATE2MBS(r)   (((r) & IEEE80211_RATE_VAL) / 2)
  70
  71 static  void adhoc_vattach(struct ieee80211vap *);
  72 static  int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
  73 static int adhoc_input(struct ieee80211_node *, struct mbuf *,
  74             const struct ieee80211_rx_stats *, int, int);
  75 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
  76         int subtype, const struct ieee80211_rx_stats *, int, int);
  77 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
  78             int subtype, const struct ieee80211_rx_stats *rxs, int, int);
  79 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
  80
  81 void
  82 ieee80211_adhoc_attach(struct ieee80211com *ic)
  83 {
  84         ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
  85         ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
  86 }
  87
  88 void
  89 ieee80211_adhoc_detach(struct ieee80211com *ic)
  90 {
  91 }
  92
  93 static void
  94 adhoc_vdetach(struct ieee80211vap *vap)
  95 {
  96 }
  97
  98 static void
  99 adhoc_vattach(struct ieee80211vap *vap)
 100 {
 101         vap->iv_newstate = adhoc_newstate;
 102         vap->iv_input = adhoc_input;
 103         if (vap->iv_opmode == IEEE80211_M_IBSS)
 104                 vap->iv_recv_mgmt = adhoc_recv_mgmt;
 105         else
 106                 vap->iv_recv_mgmt = ahdemo_recv_mgmt;
 107         vap->iv_recv_ctl = adhoc_recv_ctl;
 108         vap->iv_opdetach = adhoc_vdetach;
 109 #ifdef IEEE80211_SUPPORT_TDMA
 110         /*
 111          * Throw control to tdma support.  Note we do this
 112          * after setting up our callbacks so it can piggyback
 113          * on top of us.
 114          */
 115         if (vap->iv_caps & IEEE80211_C_TDMA)
 116                 ieee80211_tdma_vattach(vap);
 117 #endif
 118 }
 119
 120 static void
 121 sta_leave(void *arg, struct ieee80211_node *ni)
 122 {
 123         struct ieee80211vap *vap = arg;
 124
 125         if (ni->ni_vap == vap && ni != vap->iv_bss)
 126                 ieee80211_node_leave(ni);
 127 }
 128
 129 /*
 130  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
 131  */
 132 static int
 133 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
 134 {
 135         struct ieee80211com *ic = vap->iv_ic;
 136         struct ieee80211_node *ni;
 137         enum ieee80211_state ostate;
 138
 139         IEEE80211_LOCK_ASSERT(vap->iv_ic);
 140
 141         ostate = vap->iv_state;
 142         IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
 143             __func__, ieee80211_state_name[ostate],
 144             ieee80211_state_name[nstate], arg);
 145         vap->iv_state = nstate;                 /* state transition */
 146         if (ostate != IEEE80211_S_SCAN)
 147                 ieee80211_cancel_scan(vap);     /* background scan */
 148         ni = vap->iv_bss;                       /* NB: no reference held */
 149         switch (nstate) {
 150         case IEEE80211_S_INIT:
 151                 switch (ostate) {
 152                 case IEEE80211_S_SCAN:
 153                         ieee80211_cancel_scan(vap);
 154                         break;
 155                 default:
 156                         break;
 157                 }
 158                 if (ostate != IEEE80211_S_INIT) {
 159                         /* NB: optimize INIT -> INIT case */
 160                         ieee80211_reset_bss(vap);
 161                 }
 162                 break;
 163         case IEEE80211_S_SCAN:
 164                 switch (ostate) {
 165                 case IEEE80211_S_RUN:           /* beacon miss */
 166                         /* purge station table; entries are stale */
 167                         ieee80211_iterate_nodes(&ic->ic_sta, sta_leave, vap);
 168                         /* fall thru... */
 169                 case IEEE80211_S_INIT:
 170                         if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
 171                             !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
 172                                 /*
 173                                  * Already have a channel; bypass the
 174                                  * scan and startup immediately.
 175                                  */
 176                                 ieee80211_create_ibss(vap,
 177                                     ieee80211_ht_adjust_channel(ic,
 178                                     vap->iv_des_chan, vap->iv_flags_ht));
 179                                 break;
 180                         }
 181                         /*
 182                          * Initiate a scan.  We can come here as a result
 183                          * of an IEEE80211_IOC_SCAN_REQ too in which case
 184                          * the vap will be marked with IEEE80211_FEXT_SCANREQ
 185                          * and the scan request parameters will be present
 186                          * in iv_scanreq.  Otherwise we do the default.
 187                          */
 188                         if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
 189                                 ieee80211_check_scan(vap,
 190                                     vap->iv_scanreq_flags,
 191                                     vap->iv_scanreq_duration,
 192                                     vap->iv_scanreq_mindwell,
 193                                     vap->iv_scanreq_maxdwell,
 194                                     vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
 195                                 vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
 196                         } else
 197                                 ieee80211_check_scan_current(vap);
 198                         break;
 199                 case IEEE80211_S_SCAN:
 200                         /*
 201                          * This can happen because of a change in state
 202                          * that requires a reset.  Trigger a new scan
 203                          * unless we're in manual roaming mode in which
 204                          * case an application must issue an explicit request.
 205                          */
 206                         if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
 207                                 ieee80211_check_scan_current(vap);
 208                         break;
 209                 default:
 210                         goto invalid;
 211                 }
 212                 break;
 213         case IEEE80211_S_RUN:
 214                 if (vap->iv_flags & IEEE80211_F_WPA) {
 215                         /* XXX validate prerequisites */
 216                 }
 217                 switch (ostate) {
 218                 case IEEE80211_S_SCAN:
 219 #ifdef IEEE80211_DEBUG
 220                         if (ieee80211_msg_debug(vap)) {
 221                                 ieee80211_note(vap,
 222                                     "synchronized with %s ssid ",
 223                                     ether_sprintf(ni->ni_bssid));
 224                                 ieee80211_print_essid(vap->iv_bss->ni_essid,
 225                                     ni->ni_esslen);
 226                                 /* XXX MCS/HT */
 227                                 printf(" channel %d start %uMb\n",
 228                                     ieee80211_chan2ieee(ic, ic->ic_curchan),
 229                                     IEEE80211_RATE2MBS(ni->ni_txrate));
 230                         }
 231 #endif
 232                         break;
 233                 case IEEE80211_S_RUN:   /* IBSS merge */
 234                         break;
 235                 default:
 236                         goto invalid;
 237                 }
 238                 /*
 239                  * When 802.1x is not in use mark the port authorized
 240                  * at this point so traffic can flow.
 241                  */
 242                 if (ni->ni_authmode != IEEE80211_AUTH_8021X)
 243                         ieee80211_node_authorize(ni);
 244                 /*
 245                  * Fake association when joining an existing bss.
 246                  */
 247                 if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
 248                     ic->ic_newassoc != NULL)
 249                         ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
 250                 break;
 251         case IEEE80211_S_SLEEP:
 252                 vap->iv_sta_ps(vap, 0);
 253                 break;
 254         default:
 255         invalid:
 256                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
 257                     "%s: unexpected state transition %s -> %s\n", __func__,
 258                     ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
 259                 break;
 260         }
 261         return 0;
 262 }
 263
 264 /*
 265  * Decide if a received management frame should be
 266  * printed when debugging is enabled.  This filters some
 267  * of the less interesting frames that come frequently
 268  * (e.g. beacons).
 269  */
 270 static __inline int
 271 doprint(struct ieee80211vap *vap, int subtype)
 272 {
 273         switch (subtype) {
 274         case IEEE80211_FC0_SUBTYPE_BEACON:
 275                 return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
 276         case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 277                 return 1;
 278         }
 279         return 1;
 280 }
 281
 282 /*
 283  * Process a received frame.  The node associated with the sender
 284  * should be supplied.  If nothing was found in the node table then
 285  * the caller is assumed to supply a reference to iv_bss instead.
 286  * The RSSI and a timestamp are also supplied.  The RSSI data is used
 287  * during AP scanning to select a AP to associate with; it can have
 288  * any units so long as values have consistent units and higher values
 289  * mean ``better signal''.  The receive timestamp is currently not used
 290  * by the 802.11 layer.
 291  */
 292 static int
 293 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
 294     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 295 {
 296         struct ieee80211vap *vap = ni->ni_vap;
 297         struct ieee80211com *ic = ni->ni_ic;
 298         struct ifnet *ifp = vap->iv_ifp;
 299         struct ieee80211_frame *wh;
 300         struct ieee80211_key *key;
 301         struct ether_header *eh;
 302         int hdrspace, need_tap = 1;     /* mbuf need to be tapped. */
 303         uint8_t dir, type, subtype, qos;
 304         uint8_t *bssid;
 305
 306         if (m->m_flags & M_AMPDU_MPDU) {
 307                 /*
 308                  * Fastpath for A-MPDU reorder q resubmission.  Frames
 309                  * w/ M_AMPDU_MPDU marked have already passed through
 310                  * here but were received out of order and been held on
 311                  * the reorder queue.  When resubmitted they are marked
 312                  * with the M_AMPDU_MPDU flag and we can bypass most of
 313                  * the normal processing.
 314                  */
 315                 wh = mtod(m, struct ieee80211_frame *);
 316                 type = IEEE80211_FC0_TYPE_DATA;
 317                 dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
 318                 subtype = IEEE80211_FC0_SUBTYPE_QOS;
 319                 hdrspace = ieee80211_hdrspace(ic, wh);  /* XXX optimize? */
 320                 goto resubmit_ampdu;
 321         }
 322
 323         KASSERT(ni != NULL, ("null node"));
 324         ni->ni_inact = ni->ni_inact_reload;
 325
 326         type = -1;                      /* undefined */
 327
 328         if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
 329                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 330                     ni->ni_macaddr, NULL,
 331                     "too short (1): len %u", m->m_pkthdr.len);
 332                 vap->iv_stats.is_rx_tooshort++;
 333                 goto out;
 334         }
 335         /*
 336          * Bit of a cheat here, we use a pointer for a 3-address
 337          * frame format but don't reference fields past outside
 338          * ieee80211_frame_min w/o first validating the data is
 339          * present.
 340          */
 341         wh = mtod(m, struct ieee80211_frame *);
 342
 343         if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
 344             IEEE80211_FC0_VERSION_0) {
 345                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 346                     ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
 347                     wh->i_fc[0], wh->i_fc[1]);
 348                 vap->iv_stats.is_rx_badversion++;
 349                 goto err;
 350         }
 351
 352         dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
 353         type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
 354         subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
 355         if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
 356                 if (dir != IEEE80211_FC1_DIR_NODS)
 357                         bssid = wh->i_addr1;
 358                 else if (type == IEEE80211_FC0_TYPE_CTL)
 359                         bssid = wh->i_addr1;
 360                 else {
 361                         if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
 362                                 IEEE80211_DISCARD_MAC(vap,
 363                                     IEEE80211_MSG_ANY, ni->ni_macaddr,
 364                                     NULL, "too short (2): len %u",
 365                                     m->m_pkthdr.len);
 366                                 vap->iv_stats.is_rx_tooshort++;
 367                                 goto out;
 368                         }
 369                         bssid = wh->i_addr3;
 370                 }
 371                 /*
 372                  * Validate the bssid.
 373                  */
 374                 if (!(type == IEEE80211_FC0_TYPE_MGT &&
 375                      (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
 376                       subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) &&
 377                     !IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
 378                     !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
 379                         /* not interested in */
 380                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 381                             bssid, NULL, "%s", "not to bss");
 382                         vap->iv_stats.is_rx_wrongbss++;
 383                         goto out;
 384                 }
 385                 /*
 386                  * Data frame, cons up a node when it doesn't
 387                  * exist. This should probably done after an ACL check.
 388                  */
 389                 if (type == IEEE80211_FC0_TYPE_DATA &&
 390                     ni == vap->iv_bss &&
 391                     !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 392                         /*
 393                          * Beware of frames that come in too early; we
 394                          * can receive broadcast frames and creating sta
 395                          * entries will blow up because there is no bss
 396                          * channel yet.
 397                          */
 398                         if (vap->iv_state != IEEE80211_S_RUN) {
 399                                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 400                                     wh, "data", "not in RUN state (%s)",
 401                                     ieee80211_state_name[vap->iv_state]);
 402                                 vap->iv_stats.is_rx_badstate++;
 403                                 goto err;
 404                         }
 405                         /*
 406                          * Fake up a node for this newly
 407                          * discovered member of the IBSS.
 408                          */
 409                         ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
 410                         if (ni == NULL) {
 411                                 /* NB: stat kept for alloc failure */
 412                                 goto err;
 413                         }
 414                 }
 415                 IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
 416                 ni->ni_noise = nf;
 417                 if (IEEE80211_HAS_SEQ(type, subtype) &&
 418                     IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 419                         uint8_t tid = ieee80211_gettid(wh);
 420                         if (IEEE80211_QOS_HAS_SEQ(wh) &&
 421                             TID_TO_WME_AC(tid) >= WME_AC_VI)
 422                                 ic->ic_wme.wme_hipri_traffic++;
 423                         if (! ieee80211_check_rxseq(ni, wh, bssid))
 424                                 goto out;
 425                 }
 426         }
 427
 428         switch (type) {
 429         case IEEE80211_FC0_TYPE_DATA:
 430                 hdrspace = ieee80211_hdrspace(ic, wh);
 431                 if (m->m_len < hdrspace &&
 432                     (m = m_pullup(m, hdrspace)) == NULL) {
 433                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 434                             ni->ni_macaddr, NULL,
 435                             "data too short: expecting %u", hdrspace);
 436                         vap->iv_stats.is_rx_tooshort++;
 437                         goto out;               /* XXX */
 438                 }
 439                 if (dir != IEEE80211_FC1_DIR_NODS) {
 440                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 441                             wh, "data", "incorrect dir 0x%x", dir);
 442                         vap->iv_stats.is_rx_wrongdir++;
 443                         goto out;
 444                 }
 445                 /* XXX no power-save support */
 446
 447                 /*
 448                  * Handle A-MPDU re-ordering.  If the frame is to be
 449                  * processed directly then ieee80211_ampdu_reorder
 450                  * will return 0; otherwise it has consumed the mbuf
 451                  * and we should do nothing more with it.
 452                  */
 453                 if ((m->m_flags & M_AMPDU) &&
 454                     ieee80211_ampdu_reorder(ni, m) != 0) {
 455                         m = NULL;
 456                         goto out;
 457                 }
 458         resubmit_ampdu:
 459
 460                 /*
 461                  * Handle privacy requirements.  Note that we
 462                  * must not be preempted from here until after
 463                  * we (potentially) call ieee80211_crypto_demic;
 464                  * otherwise we may violate assumptions in the
 465                  * crypto cipher modules used to do delayed update
 466                  * of replay sequence numbers.
 467                  */
 468                 if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 469                         if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
 470                                 /*
 471                                  * Discard encrypted frames when privacy is off.
 472                                  */
 473                                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 474                                     wh, "WEP", "%s", "PRIVACY off");
 475                                 vap->iv_stats.is_rx_noprivacy++;
 476                                 IEEE80211_NODE_STAT(ni, rx_noprivacy);
 477                                 goto out;
 478                         }
 479                         key = ieee80211_crypto_decap(ni, m, hdrspace);
 480                         if (key == NULL) {
 481                                 /* NB: stats+msgs handled in crypto_decap */
 482                                 IEEE80211_NODE_STAT(ni, rx_wepfail);
 483                                 goto out;
 484                         }
 485                         wh = mtod(m, struct ieee80211_frame *);
 486                         wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
 487                 } else {
 488                         /* XXX M_WEP and IEEE80211_F_PRIVACY */
 489                         key = NULL;
 490                 }
 491
 492                 /*
 493                  * Save QoS bits for use below--before we strip the header.
 494                  */
 495                 if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
 496                         qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
 497                             ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
 498                             ((struct ieee80211_qosframe *)wh)->i_qos[0];
 499                 } else
 500                         qos = 0;
 501
 502                 /*
 503                  * Next up, any fragmentation.
 504                  */
 505                 if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
 506                         m = ieee80211_defrag(ni, m, hdrspace);
 507                         if (m == NULL) {
 508                                 /* Fragment dropped or frame not complete yet */
 509                                 goto out;
 510                         }
 511                 }
 512                 wh = NULL;              /* no longer valid, catch any uses */
 513
 514                 /*
 515                  * Next strip any MSDU crypto bits.
 516                  */
 517                 if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
 518                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 519                             ni->ni_macaddr, "data", "%s", "demic error");
 520                         vap->iv_stats.is_rx_demicfail++;
 521                         IEEE80211_NODE_STAT(ni, rx_demicfail);
 522                         goto out;
 523                 }
 524
 525                 /* copy to listener after decrypt */
 526                 if (ieee80211_radiotap_active_vap(vap))
 527                         ieee80211_radiotap_rx(vap, m);
 528                 need_tap = 0;
 529
 530                 /*
 531                  * Finally, strip the 802.11 header.
 532                  */
 533                 m = ieee80211_decap(vap, m, hdrspace);
 534                 if (m == NULL) {
 535                         /* XXX mask bit to check for both */
 536                         /* don't count Null data frames as errors */
 537                         if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
 538                             subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
 539                                 goto out;
 540                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 541                             ni->ni_macaddr, "data", "%s", "decap error");
 542                         vap->iv_stats.is_rx_decap++;
 543                         IEEE80211_NODE_STAT(ni, rx_decap);
 544                         goto err;
 545                 }
 546                 eh = mtod(m, struct ether_header *);
 547                 if (!ieee80211_node_is_authorized(ni)) {
 548                         /*
 549                          * Deny any non-PAE frames received prior to
 550                          * authorization.  For open/shared-key
 551                          * authentication the port is mark authorized
 552                          * after authentication completes.  For 802.1x
 553                          * the port is not marked authorized by the
 554                          * authenticator until the handshake has completed.
 555                          */
 556                         if (eh->ether_type != htons(ETHERTYPE_PAE)) {
 557                                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 558                                     eh->ether_shost, "data",
 559                                     "unauthorized port: ether type 0x%x len %u",
 560                                     eh->ether_type, m->m_pkthdr.len);
 561                                 vap->iv_stats.is_rx_unauth++;
 562                                 IEEE80211_NODE_STAT(ni, rx_unauth);
 563                                 goto err;
 564                         }
 565                 } else {
 566                         /*
 567                          * When denying unencrypted frames, discard
 568                          * any non-PAE frames received without encryption.
 569                          */
 570                         if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
 571                             (key == NULL && (m->m_flags & M_WEP) == 0) &&
 572                             eh->ether_type != htons(ETHERTYPE_PAE)) {
 573                                 /*
 574                                  * Drop unencrypted frames.
 575                                  */
 576                                 vap->iv_stats.is_rx_unencrypted++;
 577                                 IEEE80211_NODE_STAT(ni, rx_unencrypted);
 578                                 goto out;
 579                         }
 580                 }
 581                 /* XXX require HT? */
 582                 if (qos & IEEE80211_QOS_AMSDU) {
 583                         m = ieee80211_decap_amsdu(ni, m);
 584                         if (m == NULL)
 585                                 return IEEE80211_FC0_TYPE_DATA;
 586                 } else {
 587 #ifdef IEEE80211_SUPPORT_SUPERG
 588                         m = ieee80211_decap_fastframe(vap, ni, m);
 589                         if (m == NULL)
 590                                 return IEEE80211_FC0_TYPE_DATA;
 591 #endif
 592                 }
 593                 if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
 594                         ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
 595                 else
 596                         ieee80211_deliver_data(vap, ni, m);
 597                 return IEEE80211_FC0_TYPE_DATA;
 598
 599         case IEEE80211_FC0_TYPE_MGT:
 600                 vap->iv_stats.is_rx_mgmt++;
 601                 IEEE80211_NODE_STAT(ni, rx_mgmt);
 602                 if (dir != IEEE80211_FC1_DIR_NODS) {
 603                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 604                             wh, "data", "incorrect dir 0x%x", dir);
 605                         vap->iv_stats.is_rx_wrongdir++;
 606                         goto err;
 607                 }
 608                 if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
 609                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 610                             ni->ni_macaddr, "mgt", "too short: len %u",
 611                             m->m_pkthdr.len);
 612                         vap->iv_stats.is_rx_tooshort++;
 613                         goto out;
 614                 }
 615 #ifdef IEEE80211_DEBUG
 616                 if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
 617                     ieee80211_msg_dumppkts(vap)) {
 618                         if_printf(ifp, "received %s from %s rssi %d\n",
 619                             ieee80211_mgt_subtype_name(subtype),
 620                             ether_sprintf(wh->i_addr2), rssi);
 621                 }
 622 #endif
 623                 if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 624                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 625                             wh, NULL, "%s", "WEP set but not permitted");
 626                         vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
 627                         goto out;
 628                 }
 629                 vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
 630                 goto out;
 631
 632         case IEEE80211_FC0_TYPE_CTL:
 633                 vap->iv_stats.is_rx_ctl++;
 634                 IEEE80211_NODE_STAT(ni, rx_ctrl);
 635                 vap->iv_recv_ctl(ni, m, subtype);
 636                 goto out;
 637
 638         default:
 639                 IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
 640                     wh, "bad", "frame type 0x%x", type);
 641                 /* should not come here */
 642                 break;
 643         }
 644 err:
 645         if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
 646 out:
 647         if (m != NULL) {
 648                 if (need_tap && ieee80211_radiotap_active_vap(vap))
 649                         ieee80211_radiotap_rx(vap, m);
 650                 m_freem(m);
 651         }
 652         return type;
 653 }
 654
 655 static int
 656 is11bclient(const uint8_t *rates, const uint8_t *xrates)
 657 {
 658         static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
 659         int i;
 660
 661         /* NB: the 11b clients we care about will not have xrates */
 662         if (xrates != NULL || rates == NULL)
 663                 return 0;
 664         for (i = 0; i < rates[1]; i++) {
 665                 int r = rates[2+i] & IEEE80211_RATE_VAL;
 666                 if (r > 2*11 || ((1<<r) & brates) == 0)
 667                         return 0;
 668         }
 669         return 1;
 670 }
 671
 672 static void
 673 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 674         int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 675 {
 676         struct ieee80211vap *vap = ni->ni_vap;
 677         struct ieee80211com *ic = ni->ni_ic;
 678         struct ieee80211_channel *rxchan = ic->ic_curchan;
 679         struct ieee80211_frame *wh;
 680         uint8_t *frm, *efrm;
 681         uint8_t *ssid, *rates, *xrates;
 682 #if 0
 683         int ht_state_change = 0;
 684 #endif
 685
 686         wh = mtod(m0, struct ieee80211_frame *);
 687         frm = (uint8_t *)&wh[1];
 688         efrm = mtod(m0, uint8_t *) + m0->m_len;
 689         switch (subtype) {
 690         case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
 691         case IEEE80211_FC0_SUBTYPE_BEACON: {
 692                 struct ieee80211_scanparams scan;
 693                 struct ieee80211_channel *c;
 694                 /*
 695                  * We process beacon/probe response
 696                  * frames to discover neighbors.
 697                  */
 698                 if (rxs != NULL) {
 699                         c = ieee80211_lookup_channel_rxstatus(vap, rxs);
 700                         if (c != NULL)
 701                                 rxchan = c;
 702                 }
 703                 if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
 704                         return;
 705                 /*
 706                  * Count frame now that we know it's to be processed.
 707                  */
 708                 if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
 709                         vap->iv_stats.is_rx_beacon++;           /* XXX remove */
 710                         IEEE80211_NODE_STAT(ni, rx_beacons);
 711                 } else
 712                         IEEE80211_NODE_STAT(ni, rx_proberesp);
 713                 /*
 714                  * If scanning, just pass information to the scan module.
 715                  */
 716                 if (ic->ic_flags & IEEE80211_F_SCAN) {
 717                         if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
 718                                 /*
 719                                  * Actively scanning a channel marked passive;
 720                                  * send a probe request now that we know there
 721                                  * is 802.11 traffic present.
 722                                  *
 723                                  * XXX check if the beacon we recv'd gives
 724                                  * us what we need and suppress the probe req
 725                                  */
 726                                 ieee80211_probe_curchan(vap, 1);
 727                                 ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
 728                         }
 729                         ieee80211_add_scan(vap, rxchan, &scan, wh,
 730                             subtype, rssi, nf);
 731                         return;
 732                 }
 733                 if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
 734                         if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 735                                 /*
 736                                  * Create a new entry in the neighbor table.
 737                                  */
 738                                 ni = ieee80211_add_neighbor(vap, wh, &scan);
 739                         } else if (ni->ni_capinfo == 0) {
 740                                 /*
 741                                  * Update faked node created on transmit.
 742                                  * Note this also updates the tsf.
 743                                  */
 744                                 ieee80211_init_neighbor(ni, wh, &scan);
 745                         } else {
 746                                 /*
 747                                  * Record tsf for potential resync.
 748                                  */
 749                                 memcpy(ni->ni_tstamp.data, scan.tstamp,
 750                                         sizeof(ni->ni_tstamp));
 751                         }
 752                         /*
 753                          * This isn't enabled yet - otherwise it would
 754                          * update the HT parameters and channel width
 755                          * from any node, which could lead to lots of
 756                          * strange behaviour if the 11n nodes aren't
 757                          * exactly configured to match.
 758                          */
 759 #if 0
 760                         if (scan.htcap != NULL && scan.htinfo != NULL &&
 761                             (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
 762                                 if (ieee80211_ht_updateparams(ni,
 763                                     scan.htcap, scan.htinfo))
 764                                         ht_state_change = 1;
 765                         }
 766 #endif
 767                         if (ni != NULL) {
 768                                 IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
 769                                 ni->ni_noise = nf;
 770                         }
 771                         /*
 772                          * Same here - the channel width change should
 773                          * be applied to the specific peer node, not
 774                          * to the ic.  Ie, the interface configuration
 775                          * should stay in its current channel width;
 776                          * but it should change the rate control and
 777                          * any queued frames for the given node only.
 778                          *
 779                          * Since there's no (current) way to inform
 780                          * the driver that a channel width change has
 781                          * occurred for a single node, just stub this
 782                          * out.
 783                          */
 784 #if 0
 785                         if (ht_state_change)
 786                                 ieee80211_update_chw(ic);
 787 #endif
 788                 }
 789                 break;
 790         }
 791
 792         case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 793                 if (vap->iv_state != IEEE80211_S_RUN) {
 794                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 795                             wh, NULL, "wrong state %s",
 796                             ieee80211_state_name[vap->iv_state]);
 797                         vap->iv_stats.is_rx_mgtdiscard++;
 798                         return;
 799                 }
 800                 if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
 801                         /* frame must be directed */
 802                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 803                             wh, NULL, "%s", "not unicast");
 804                         vap->iv_stats.is_rx_mgtdiscard++;       /* XXX stat */
 805                         return;
 806                 }
 807
 808                 /*
 809                  * prreq frame format
 810                  *      [tlv] ssid
 811                  *      [tlv] supported rates
 812                  *      [tlv] extended supported rates
 813                  */
 814                 ssid = rates = xrates = NULL;
 815                 while (efrm - frm > 1) {
 816                         IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
 817                         switch (*frm) {
 818                         case IEEE80211_ELEMID_SSID:
 819                                 ssid = frm;
 820                                 break;
 821                         case IEEE80211_ELEMID_RATES:
 822                                 rates = frm;
 823                                 break;
 824                         case IEEE80211_ELEMID_XRATES:
 825                                 xrates = frm;
 826                                 break;
 827                         }
 828                         frm += frm[1] + 2;
 829                 }
 830                 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
 831                 if (xrates != NULL)
 832                         IEEE80211_VERIFY_ELEMENT(xrates,
 833                                 IEEE80211_RATE_MAXSIZE - rates[1], return);
 834                 IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
 835                 IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
 836                 if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
 837                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 838                             wh, NULL,
 839                             "%s", "no ssid with ssid suppression enabled");
 840                         vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
 841                         return;
 842                 }
 843
 844                 /* XXX find a better class or define it's own */
 845                 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
 846                     "%s", "recv probe req");
 847                 /*
 848                  * Some legacy 11b clients cannot hack a complete
 849                  * probe response frame.  When the request includes
 850                  * only a bare-bones rate set, communicate this to
 851                  * the transmit side.
 852                  */
 853                 ieee80211_send_proberesp(vap, wh->i_addr2,
 854                     is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
 855                 break;
 856
 857         case IEEE80211_FC0_SUBTYPE_ACTION:
 858         case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
 859                 if ((ni == vap->iv_bss) &&
 860                     !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 861                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 862                             wh, NULL, "%s", "unknown node");
 863                         vap->iv_stats.is_rx_mgtdiscard++;
 864                 } else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
 865                     !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
 866                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 867                             wh, NULL, "%s", "not for us");
 868                         vap->iv_stats.is_rx_mgtdiscard++;
 869                 } else if (vap->iv_state != IEEE80211_S_RUN) {
 870                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 871                             wh, NULL, "wrong state %s",
 872                             ieee80211_state_name[vap->iv_state]);
 873                         vap->iv_stats.is_rx_mgtdiscard++;
 874                 } else {
 875                         if (ieee80211_parse_action(ni, m0) == 0)
 876                                 (void)ic->ic_recv_action(ni, wh, frm, efrm);
 877                 }
 878                 break;
 879
 880         case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
 881         case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
 882         case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
 883         case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
 884         case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
 885         case IEEE80211_FC0_SUBTYPE_ATIM:
 886         case IEEE80211_FC0_SUBTYPE_DISASSOC:
 887         case IEEE80211_FC0_SUBTYPE_AUTH:
 888         case IEEE80211_FC0_SUBTYPE_DEAUTH:
 889                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 890                     wh, NULL, "%s", "not handled");
 891                 vap->iv_stats.is_rx_mgtdiscard++;
 892                 break;
 893
 894         default:
 895                 IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
 896                     wh, "mgt", "subtype 0x%x not handled", subtype);
 897                 vap->iv_stats.is_rx_badsubtype++;
 898                 break;
 899         }
 900 }
 901 #undef IEEE80211_VERIFY_LENGTH
 902 #undef IEEE80211_VERIFY_ELEMENT
 903
 904 static void
 905 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 906         int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 907 {
 908         struct ieee80211vap *vap = ni->ni_vap;
 909         struct ieee80211com *ic = ni->ni_ic;
 910         struct ieee80211_frame *wh;
 911
 912         /*
 913          * Process management frames when scanning; useful for doing
 914          * a site-survey.
 915          */
 916         if (ic->ic_flags & IEEE80211_F_SCAN)
 917                 adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
 918         else {
 919                 wh = mtod(m0, struct ieee80211_frame *);
 920                 switch (subtype) {
 921                 case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
 922                 case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
 923                 case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
 924                 case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
 925                 case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 926                 case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
 927                 case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
 928                 case IEEE80211_FC0_SUBTYPE_BEACON:
 929                 case IEEE80211_FC0_SUBTYPE_ATIM:
 930                 case IEEE80211_FC0_SUBTYPE_DISASSOC:
 931                 case IEEE80211_FC0_SUBTYPE_AUTH:
 932                 case IEEE80211_FC0_SUBTYPE_DEAUTH:
 933                 case IEEE80211_FC0_SUBTYPE_ACTION:
 934                 case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
 935                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 936                              wh, NULL, "%s", "not handled");
 937                         vap->iv_stats.is_rx_mgtdiscard++;
 938                         break;
 939                 default:
 940                         IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
 941                              wh, "mgt", "subtype 0x%x not handled", subtype);
 942                         vap->iv_stats.is_rx_badsubtype++;
 943                         break;
 944                 }
 945         }
 946 }
 947
 948 static void
 949 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
 950 {
 951
 952         switch (subtype) {
 953         case IEEE80211_FC0_SUBTYPE_BAR:
 954                 ieee80211_recv_bar(ni, m);
 955                 break;
 956         }
 957 }