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 = ni->ni_vap;
 124
 125         if (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_vap(&ic->ic_sta, vap,
 168                             sta_leave, NULL);
 169                         /* fall thru... */
 170                 case IEEE80211_S_INIT:
 171                         if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
 172                             !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
 173                                 /*
 174                                  * Already have a channel; bypass the
 175                                  * scan and startup immediately.
 176                                  */
 177                                 ieee80211_create_ibss(vap,
 178                                     ieee80211_ht_adjust_channel(ic,
 179                                     vap->iv_des_chan, vap->iv_flags_ht));
 180                                 break;
 181                         }
 182                         /*
 183                          * Initiate a scan.  We can come here as a result
 184                          * of an IEEE80211_IOC_SCAN_REQ too in which case
 185                          * the vap will be marked with IEEE80211_FEXT_SCANREQ
 186                          * and the scan request parameters will be present
 187                          * in iv_scanreq.  Otherwise we do the default.
 188                          */
 189                         if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
 190                                 ieee80211_check_scan(vap,
 191                                     vap->iv_scanreq_flags,
 192                                     vap->iv_scanreq_duration,
 193                                     vap->iv_scanreq_mindwell,
 194                                     vap->iv_scanreq_maxdwell,
 195                                     vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
 196                                 vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
 197                         } else
 198                                 ieee80211_check_scan_current(vap);
 199                         break;
 200                 case IEEE80211_S_SCAN:
 201                         /*
 202                          * This can happen because of a change in state
 203                          * that requires a reset.  Trigger a new scan
 204                          * unless we're in manual roaming mode in which
 205                          * case an application must issue an explicit request.
 206                          */
 207                         if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
 208                                 ieee80211_check_scan_current(vap);
 209                         break;
 210                 default:
 211                         goto invalid;
 212                 }
 213                 break;
 214         case IEEE80211_S_RUN:
 215                 if (vap->iv_flags & IEEE80211_F_WPA) {
 216                         /* XXX validate prerequisites */
 217                 }
 218                 switch (ostate) {
 219                 case IEEE80211_S_INIT:
 220                         /*
 221                          * Already have a channel; bypass the
 222                          * scan and startup immediately.
 223                          * Note that ieee80211_create_ibss will call
 224                          * back to do a RUN->RUN state change.
 225                          */
 226                         ieee80211_create_ibss(vap,
 227                             ieee80211_ht_adjust_channel(ic,
 228                                 ic->ic_curchan, vap->iv_flags_ht));
 229                         /* NB: iv_bss is changed on return */
 230                         ni = vap->iv_bss;
 231                         break;
 232                 case IEEE80211_S_SCAN:
 233 #ifdef IEEE80211_DEBUG
 234                         if (ieee80211_msg_debug(vap)) {
 235                                 ieee80211_note(vap,
 236                                     "synchronized with %s ssid ",
 237                                     ether_sprintf(ni->ni_bssid));
 238                                 ieee80211_print_essid(vap->iv_bss->ni_essid,
 239                                     ni->ni_esslen);
 240                                 /* XXX MCS/HT */
 241                                 printf(" channel %d start %uMb\n",
 242                                     ieee80211_chan2ieee(ic, ic->ic_curchan),
 243                                     IEEE80211_RATE2MBS(ni->ni_txrate));
 244                         }
 245 #endif
 246                         break;
 247                 case IEEE80211_S_RUN:   /* IBSS merge */
 248                         break;
 249                 default:
 250                         goto invalid;
 251                 }
 252                 /*
 253                  * When 802.1x is not in use mark the port authorized
 254                  * at this point so traffic can flow.
 255                  */
 256                 if (ni->ni_authmode != IEEE80211_AUTH_8021X)
 257                         ieee80211_node_authorize(ni);
 258                 /*
 259                  * Fake association when joining an existing bss.
 260                  */
 261                 if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
 262                     ic->ic_newassoc != NULL)
 263                         ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
 264                 break;
 265         case IEEE80211_S_SLEEP:
 266                 vap->iv_sta_ps(vap, 0);
 267                 break;
 268         default:
 269         invalid:
 270                 IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
 271                     "%s: unexpected state transition %s -> %s\n", __func__,
 272                     ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
 273                 break;
 274         }
 275         return 0;
 276 }
 277
 278 /*
 279  * Decide if a received management frame should be
 280  * printed when debugging is enabled.  This filters some
 281  * of the less interesting frames that come frequently
 282  * (e.g. beacons).
 283  */
 284 static __inline int
 285 doprint(struct ieee80211vap *vap, int subtype)
 286 {
 287         switch (subtype) {
 288         case IEEE80211_FC0_SUBTYPE_BEACON:
 289                 return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
 290         case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 291                 return 1;
 292         }
 293         return 1;
 294 }
 295
 296 /*
 297  * Process a received frame.  The node associated with the sender
 298  * should be supplied.  If nothing was found in the node table then
 299  * the caller is assumed to supply a reference to iv_bss instead.
 300  * The RSSI and a timestamp are also supplied.  The RSSI data is used
 301  * during AP scanning to select a AP to associate with; it can have
 302  * any units so long as values have consistent units and higher values
 303  * mean ``better signal''.  The receive timestamp is currently not used
 304  * by the 802.11 layer.
 305  */
 306 static int
 307 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
 308     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 309 {
 310         struct ieee80211vap *vap = ni->ni_vap;
 311         struct ieee80211com *ic = ni->ni_ic;
 312         struct ifnet *ifp = vap->iv_ifp;
 313         struct ieee80211_frame *wh;
 314         struct ieee80211_key *key;
 315         struct ether_header *eh;
 316         int hdrspace, need_tap = 1;     /* mbuf need to be tapped. */
 317         uint8_t dir, type, subtype, qos;
 318         uint8_t *bssid;
 319         int is_hw_decrypted = 0;
 320         int has_decrypted = 0;
 321
 322         /*
 323          * Some devices do hardware decryption all the way through
 324          * to pretending the frame wasn't encrypted in the first place.
 325          * So, tag it appropriately so it isn't discarded inappropriately.
 326          */
 327         if ((rxs != NULL) && (rxs->c_pktflags & IEEE80211_RX_F_DECRYPTED))
 328                 is_hw_decrypted = 1;
 329
 330         if (m->m_flags & M_AMPDU_MPDU) {
 331                 /*
 332                  * Fastpath for A-MPDU reorder q resubmission.  Frames
 333                  * w/ M_AMPDU_MPDU marked have already passed through
 334                  * here but were received out of order and been held on
 335                  * the reorder queue.  When resubmitted they are marked
 336                  * with the M_AMPDU_MPDU flag and we can bypass most of
 337                  * the normal processing.
 338                  */
 339                 wh = mtod(m, struct ieee80211_frame *);
 340                 type = IEEE80211_FC0_TYPE_DATA;
 341                 dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
 342                 subtype = IEEE80211_FC0_SUBTYPE_QOS;
 343                 hdrspace = ieee80211_hdrspace(ic, wh);  /* XXX optimize? */
 344                 goto resubmit_ampdu;
 345         }
 346
 347         KASSERT(ni != NULL, ("null node"));
 348         ni->ni_inact = ni->ni_inact_reload;
 349
 350         type = -1;                      /* undefined */
 351
 352         if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
 353                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 354                     ni->ni_macaddr, NULL,
 355                     "too short (1): len %u", m->m_pkthdr.len);
 356                 vap->iv_stats.is_rx_tooshort++;
 357                 goto out;
 358         }
 359         /*
 360          * Bit of a cheat here, we use a pointer for a 3-address
 361          * frame format but don't reference fields past outside
 362          * ieee80211_frame_min w/o first validating the data is
 363          * present.
 364          */
 365         wh = mtod(m, struct ieee80211_frame *);
 366
 367         if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
 368             IEEE80211_FC0_VERSION_0) {
 369                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 370                     ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
 371                     wh->i_fc[0], wh->i_fc[1]);
 372                 vap->iv_stats.is_rx_badversion++;
 373                 goto err;
 374         }
 375
 376         dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
 377         type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
 378         subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
 379         if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
 380                 if (dir != IEEE80211_FC1_DIR_NODS)
 381                         bssid = wh->i_addr1;
 382                 else if (type == IEEE80211_FC0_TYPE_CTL)
 383                         bssid = wh->i_addr1;
 384                 else {
 385                         if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
 386                                 IEEE80211_DISCARD_MAC(vap,
 387                                     IEEE80211_MSG_ANY, ni->ni_macaddr,
 388                                     NULL, "too short (2): len %u",
 389                                     m->m_pkthdr.len);
 390                                 vap->iv_stats.is_rx_tooshort++;
 391                                 goto out;
 392                         }
 393                         bssid = wh->i_addr3;
 394                 }
 395                 /*
 396                  * Validate the bssid.
 397                  */
 398                 if (!(type == IEEE80211_FC0_TYPE_MGT &&
 399                      (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
 400                       subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) &&
 401                     !IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
 402                     !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
 403                         /* not interested in */
 404                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 405                             bssid, NULL, "%s", "not to bss");
 406                         vap->iv_stats.is_rx_wrongbss++;
 407                         goto out;
 408                 }
 409                 /*
 410                  * Data frame, cons up a node when it doesn't
 411                  * exist. This should probably done after an ACL check.
 412                  */
 413                 if (type == IEEE80211_FC0_TYPE_DATA &&
 414                     ni == vap->iv_bss &&
 415                     !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 416                         /*
 417                          * Beware of frames that come in too early; we
 418                          * can receive broadcast frames and creating sta
 419                          * entries will blow up because there is no bss
 420                          * channel yet.
 421                          */
 422                         if (vap->iv_state != IEEE80211_S_RUN) {
 423                                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 424                                     wh, "data", "not in RUN state (%s)",
 425                                     ieee80211_state_name[vap->iv_state]);
 426                                 vap->iv_stats.is_rx_badstate++;
 427                                 goto err;
 428                         }
 429                         /*
 430                          * Fake up a node for this newly discovered member
 431                          * of the IBSS.
 432                          *
 433                          * Note: This doesn't "upgrade" the node to 11n;
 434                          * that will happen after a probe request/response
 435                          * exchange.
 436                          */
 437                         ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
 438                         if (ni == NULL) {
 439                                 /* NB: stat kept for alloc failure */
 440                                 goto err;
 441                         }
 442                 }
 443                 IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
 444                 ni->ni_noise = nf;
 445                 if (IEEE80211_HAS_SEQ(type, subtype) &&
 446                     IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 447                         uint8_t tid = ieee80211_gettid(wh);
 448                         if (IEEE80211_QOS_HAS_SEQ(wh) &&
 449                             TID_TO_WME_AC(tid) >= WME_AC_VI)
 450                                 ic->ic_wme.wme_hipri_traffic++;
 451                         if (! ieee80211_check_rxseq(ni, wh, bssid))
 452                                 goto out;
 453                 }
 454         }
 455
 456         switch (type) {
 457         case IEEE80211_FC0_TYPE_DATA:
 458                 hdrspace = ieee80211_hdrspace(ic, wh);
 459                 if (m->m_len < hdrspace &&
 460                     (m = m_pullup(m, hdrspace)) == NULL) {
 461                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 462                             ni->ni_macaddr, NULL,
 463                             "data too short: expecting %u", hdrspace);
 464                         vap->iv_stats.is_rx_tooshort++;
 465                         goto out;               /* XXX */
 466                 }
 467                 if (dir != IEEE80211_FC1_DIR_NODS) {
 468                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 469                             wh, "data", "incorrect dir 0x%x", dir);
 470                         vap->iv_stats.is_rx_wrongdir++;
 471                         goto out;
 472                 }
 473                 /* XXX no power-save support */
 474
 475                 /*
 476                  * Handle A-MPDU re-ordering.  If the frame is to be
 477                  * processed directly then ieee80211_ampdu_reorder
 478                  * will return 0; otherwise it has consumed the mbuf
 479                  * and we should do nothing more with it.
 480                  */
 481                 if ((m->m_flags & M_AMPDU) &&
 482                     ieee80211_ampdu_reorder(ni, m) != 0) {
 483                         m = NULL;
 484                         goto out;
 485                 }
 486         resubmit_ampdu:
 487
 488                 /*
 489                  * Handle privacy requirements.  Note that we
 490                  * must not be preempted from here until after
 491                  * we (potentially) call ieee80211_crypto_demic;
 492                  * otherwise we may violate assumptions in the
 493                  * crypto cipher modules used to do delayed update
 494                  * of replay sequence numbers.
 495                  */
 496                 if (is_hw_decrypted || wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 497                         if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
 498                                 /*
 499                                  * Discard encrypted frames when privacy is off.
 500                                  */
 501                                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 502                                     wh, "WEP", "%s", "PRIVACY off");
 503                                 vap->iv_stats.is_rx_noprivacy++;
 504                                 IEEE80211_NODE_STAT(ni, rx_noprivacy);
 505                                 goto out;
 506                         }
 507                         if (ieee80211_crypto_decap(ni, m, hdrspace, &key) == 0) {
 508                                 /* NB: stats+msgs handled in crypto_decap */
 509                                 IEEE80211_NODE_STAT(ni, rx_wepfail);
 510                                 goto out;
 511                         }
 512                         wh = mtod(m, struct ieee80211_frame *);
 513                         wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
 514                         has_decrypted = 1;
 515                 } else {
 516                         /* XXX M_WEP and IEEE80211_F_PRIVACY */
 517                         key = NULL;
 518                 }
 519
 520                 /*
 521                  * Save QoS bits for use below--before we strip the header.
 522                  */
 523                 if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
 524                         qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
 525                             ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
 526                             ((struct ieee80211_qosframe *)wh)->i_qos[0];
 527                 } else
 528                         qos = 0;
 529
 530                 /*
 531                  * Next up, any fragmentation.
 532                  */
 533                 if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
 534                         m = ieee80211_defrag(ni, m, hdrspace);
 535                         if (m == NULL) {
 536                                 /* Fragment dropped or frame not complete yet */
 537                                 goto out;
 538                         }
 539                 }
 540                 wh = NULL;              /* no longer valid, catch any uses */
 541
 542                 /*
 543                  * Next strip any MSDU crypto bits.
 544                  */
 545                 if (!ieee80211_crypto_demic(vap, key, m, 0)) {
 546                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 547                             ni->ni_macaddr, "data", "%s", "demic error");
 548                         vap->iv_stats.is_rx_demicfail++;
 549                         IEEE80211_NODE_STAT(ni, rx_demicfail);
 550                         goto out;
 551                 }
 552
 553                 /* copy to listener after decrypt */
 554                 if (ieee80211_radiotap_active_vap(vap))
 555                         ieee80211_radiotap_rx(vap, m);
 556                 need_tap = 0;
 557
 558                 /*
 559                  * Finally, strip the 802.11 header.
 560                  */
 561                 m = ieee80211_decap(vap, m, hdrspace);
 562                 if (m == NULL) {
 563                         /* XXX mask bit to check for both */
 564                         /* don't count Null data frames as errors */
 565                         if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
 566                             subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
 567                                 goto out;
 568                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 569                             ni->ni_macaddr, "data", "%s", "decap error");
 570                         vap->iv_stats.is_rx_decap++;
 571                         IEEE80211_NODE_STAT(ni, rx_decap);
 572                         goto err;
 573                 }
 574                 eh = mtod(m, struct ether_header *);
 575                 if (!ieee80211_node_is_authorized(ni)) {
 576                         /*
 577                          * Deny any non-PAE frames received prior to
 578                          * authorization.  For open/shared-key
 579                          * authentication the port is mark authorized
 580                          * after authentication completes.  For 802.1x
 581                          * the port is not marked authorized by the
 582                          * authenticator until the handshake has completed.
 583                          */
 584                         if (eh->ether_type != htons(ETHERTYPE_PAE)) {
 585                                 IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
 586                                     eh->ether_shost, "data",
 587                                     "unauthorized port: ether type 0x%x len %u",
 588                                     eh->ether_type, m->m_pkthdr.len);
 589                                 vap->iv_stats.is_rx_unauth++;
 590                                 IEEE80211_NODE_STAT(ni, rx_unauth);
 591                                 goto err;
 592                         }
 593                 } else {
 594                         /*
 595                          * When denying unencrypted frames, discard
 596                          * any non-PAE frames received without encryption.
 597                          */
 598                         if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
 599                             ((has_decrypted == 0) && (m->m_flags & M_WEP) == 0) &&
 600                             (is_hw_decrypted == 0) &&
 601                             eh->ether_type != htons(ETHERTYPE_PAE)) {
 602                                 /*
 603                                  * Drop unencrypted frames.
 604                                  */
 605                                 vap->iv_stats.is_rx_unencrypted++;
 606                                 IEEE80211_NODE_STAT(ni, rx_unencrypted);
 607                                 goto out;
 608                         }
 609                 }
 610                 /* XXX require HT? */
 611                 if (qos & IEEE80211_QOS_AMSDU) {
 612                         m = ieee80211_decap_amsdu(ni, m);
 613                         if (m == NULL)
 614                                 return IEEE80211_FC0_TYPE_DATA;
 615                 } else {
 616 #ifdef IEEE80211_SUPPORT_SUPERG
 617                         m = ieee80211_decap_fastframe(vap, ni, m);
 618                         if (m == NULL)
 619                                 return IEEE80211_FC0_TYPE_DATA;
 620 #endif
 621                 }
 622                 if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
 623                         ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
 624                 else
 625                         ieee80211_deliver_data(vap, ni, m);
 626                 return IEEE80211_FC0_TYPE_DATA;
 627
 628         case IEEE80211_FC0_TYPE_MGT:
 629                 vap->iv_stats.is_rx_mgmt++;
 630                 IEEE80211_NODE_STAT(ni, rx_mgmt);
 631                 if (dir != IEEE80211_FC1_DIR_NODS) {
 632                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 633                             wh, "data", "incorrect dir 0x%x", dir);
 634                         vap->iv_stats.is_rx_wrongdir++;
 635                         goto err;
 636                 }
 637                 if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
 638                         IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
 639                             ni->ni_macaddr, "mgt", "too short: len %u",
 640                             m->m_pkthdr.len);
 641                         vap->iv_stats.is_rx_tooshort++;
 642                         goto out;
 643                 }
 644 #ifdef IEEE80211_DEBUG
 645                 if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
 646                     ieee80211_msg_dumppkts(vap)) {
 647                         if_printf(ifp, "received %s from %s rssi %d\n",
 648                             ieee80211_mgt_subtype_name(subtype),
 649                             ether_sprintf(wh->i_addr2), rssi);
 650                 }
 651 #endif
 652                 if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
 653                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 654                             wh, NULL, "%s", "WEP set but not permitted");
 655                         vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
 656                         goto out;
 657                 }
 658                 vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
 659                 goto out;
 660
 661         case IEEE80211_FC0_TYPE_CTL:
 662                 vap->iv_stats.is_rx_ctl++;
 663                 IEEE80211_NODE_STAT(ni, rx_ctrl);
 664                 vap->iv_recv_ctl(ni, m, subtype);
 665                 goto out;
 666
 667         default:
 668                 IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
 669                     wh, "bad", "frame type 0x%x", type);
 670                 /* should not come here */
 671                 break;
 672         }
 673 err:
 674         if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
 675 out:
 676         if (m != NULL) {
 677                 if (need_tap && ieee80211_radiotap_active_vap(vap))
 678                         ieee80211_radiotap_rx(vap, m);
 679                 m_freem(m);
 680         }
 681         return type;
 682 }
 683
 684 static int
 685 is11bclient(const uint8_t *rates, const uint8_t *xrates)
 686 {
 687         static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
 688         int i;
 689
 690         /* NB: the 11b clients we care about will not have xrates */
 691         if (xrates != NULL || rates == NULL)
 692                 return 0;
 693         for (i = 0; i < rates[1]; i++) {
 694                 int r = rates[2+i] & IEEE80211_RATE_VAL;
 695                 if (r > 2*11 || ((1<<r) & brates) == 0)
 696                         return 0;
 697         }
 698         return 1;
 699 }
 700
 701 static void
 702 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 703         int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 704 {
 705         struct ieee80211vap *vap = ni->ni_vap;
 706         struct ieee80211com *ic = ni->ni_ic;
 707         struct ieee80211_channel *rxchan = ic->ic_curchan;
 708         struct ieee80211_frame *wh;
 709         uint8_t *frm, *efrm;
 710         uint8_t *ssid, *rates, *xrates;
 711 #if 0
 712         int ht_state_change = 0;
 713 #endif
 714
 715         wh = mtod(m0, struct ieee80211_frame *);
 716         frm = (uint8_t *)&wh[1];
 717         efrm = mtod(m0, uint8_t *) + m0->m_len;
 718         switch (subtype) {
 719         case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
 720         case IEEE80211_FC0_SUBTYPE_BEACON: {
 721                 struct ieee80211_scanparams scan;
 722                 struct ieee80211_channel *c;
 723                 /*
 724                  * We process beacon/probe response
 725                  * frames to discover neighbors.
 726                  */
 727                 if (rxs != NULL) {
 728                         c = ieee80211_lookup_channel_rxstatus(vap, rxs);
 729                         if (c != NULL)
 730                                 rxchan = c;
 731                 }
 732                 if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
 733                         return;
 734                 /*
 735                  * Count frame now that we know it's to be processed.
 736                  */
 737                 if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
 738                         vap->iv_stats.is_rx_beacon++;           /* XXX remove */
 739                         IEEE80211_NODE_STAT(ni, rx_beacons);
 740                 } else
 741                         IEEE80211_NODE_STAT(ni, rx_proberesp);
 742                 /*
 743                  * If scanning, just pass information to the scan module.
 744                  */
 745                 if (ic->ic_flags & IEEE80211_F_SCAN) {
 746                         if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
 747                                 /*
 748                                  * Actively scanning a channel marked passive;
 749                                  * send a probe request now that we know there
 750                                  * is 802.11 traffic present.
 751                                  *
 752                                  * XXX check if the beacon we recv'd gives
 753                                  * us what we need and suppress the probe req
 754                                  */
 755                                 ieee80211_probe_curchan(vap, 1);
 756                                 ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
 757                         }
 758                         ieee80211_add_scan(vap, rxchan, &scan, wh,
 759                             subtype, rssi, nf);
 760                         return;
 761                 }
 762                 if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
 763                         if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 764                                 /*
 765                                  * Create a new entry in the neighbor table.
 766                                  *
 767                                  * XXX TODO:
 768                                  *
 769                                  * Here we're not scanning; so if we have an
 770                                  * SSID then make sure it matches our SSID.
 771                                  * Otherwise this code will match on all IBSS
 772                                  * beacons/probe requests for all SSIDs,
 773                                  * filling the node table with nodes that
 774                                  * aren't ours.
 775                                  */
 776                                 if (ieee80211_ibss_node_check_new(ni, &scan)) {
 777                                         ni = ieee80211_add_neighbor(vap, wh, &scan);
 778                                         /*
 779                                          * Send a probe request so we announce 11n
 780                                          * capabilities.
 781                                          */
 782                                         ieee80211_send_probereq(ni, /* node */
 783                                             vap->iv_myaddr, /* SA */
 784                                             ni->ni_macaddr, /* DA */
 785                                             vap->iv_bss->ni_bssid, /* BSSID */
 786                                             vap->iv_bss->ni_essid,
 787                                             vap->iv_bss->ni_esslen); /* SSID */
 788                                 } else
 789                                         ni = NULL;
 790
 791                         } else if (ni->ni_capinfo == 0) {
 792                                 /*
 793                                  * Update faked node created on transmit.
 794                                  * Note this also updates the tsf.
 795                                  */
 796                                 ieee80211_init_neighbor(ni, wh, &scan);
 797
 798                                 /*
 799                                  * Send a probe request so we announce 11n
 800                                  * capabilities.
 801                                  */
 802                                 ieee80211_send_probereq(ni, /* node */
 803                                         vap->iv_myaddr, /* SA */
 804                                         ni->ni_macaddr, /* DA */
 805                                         vap->iv_bss->ni_bssid, /* BSSID */
 806                                         vap->iv_bss->ni_essid,
 807                                         vap->iv_bss->ni_esslen); /* SSID */
 808                         } else {
 809                                 /*
 810                                  * Record tsf for potential resync.
 811                                  */
 812                                 memcpy(ni->ni_tstamp.data, scan.tstamp,
 813                                         sizeof(ni->ni_tstamp));
 814                         }
 815                         /*
 816                          * This isn't enabled yet - otherwise it would
 817                          * update the HT parameters and channel width
 818                          * from any node, which could lead to lots of
 819                          * strange behaviour if the 11n nodes aren't
 820                          * exactly configured to match.
 821                          */
 822 #if 0
 823                         if (scan.htcap != NULL && scan.htinfo != NULL &&
 824                             (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
 825                                 if (ieee80211_ht_updateparams(ni,
 826                                     scan.htcap, scan.htinfo))
 827                                         ht_state_change = 1;
 828                         }
 829 #endif
 830                         if (ni != NULL) {
 831                                 IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
 832                                 ni->ni_noise = nf;
 833                         }
 834                         /*
 835                          * Same here - the channel width change should
 836                          * be applied to the specific peer node, not
 837                          * to the ic.  Ie, the interface configuration
 838                          * should stay in its current channel width;
 839                          * but it should change the rate control and
 840                          * any queued frames for the given node only.
 841                          *
 842                          * Since there's no (current) way to inform
 843                          * the driver that a channel width change has
 844                          * occurred for a single node, just stub this
 845                          * out.
 846                          */
 847 #if 0
 848                         if (ht_state_change)
 849                                 ieee80211_update_chw(ic);
 850 #endif
 851                 }
 852                 break;
 853         }
 854
 855         case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 856                 if (vap->iv_state != IEEE80211_S_RUN) {
 857                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 858                             wh, NULL, "wrong state %s",
 859                             ieee80211_state_name[vap->iv_state]);
 860                         vap->iv_stats.is_rx_mgtdiscard++;
 861                         return;
 862                 }
 863                 if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
 864                         /* frame must be directed */
 865                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 866                             wh, NULL, "%s", "not unicast");
 867                         vap->iv_stats.is_rx_mgtdiscard++;       /* XXX stat */
 868                         return;
 869                 }
 870
 871                 /*
 872                  * prreq frame format
 873                  *      [tlv] ssid
 874                  *      [tlv] supported rates
 875                  *      [tlv] extended supported rates
 876                  */
 877                 ssid = rates = xrates = NULL;
 878                 while (efrm - frm > 1) {
 879                         IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
 880                         switch (*frm) {
 881                         case IEEE80211_ELEMID_SSID:
 882                                 ssid = frm;
 883                                 break;
 884                         case IEEE80211_ELEMID_RATES:
 885                                 rates = frm;
 886                                 break;
 887                         case IEEE80211_ELEMID_XRATES:
 888                                 xrates = frm;
 889                                 break;
 890                         }
 891                         frm += frm[1] + 2;
 892                 }
 893                 IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
 894                 if (xrates != NULL)
 895                         IEEE80211_VERIFY_ELEMENT(xrates,
 896                                 IEEE80211_RATE_MAXSIZE - rates[1], return);
 897                 IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
 898                 IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
 899                 if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
 900                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 901                             wh, NULL,
 902                             "%s", "no ssid with ssid suppression enabled");
 903                         vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
 904                         return;
 905                 }
 906
 907                 /* XXX find a better class or define it's own */
 908                 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
 909                     "%s", "recv probe req");
 910                 /*
 911                  * Some legacy 11b clients cannot hack a complete
 912                  * probe response frame.  When the request includes
 913                  * only a bare-bones rate set, communicate this to
 914                  * the transmit side.
 915                  */
 916                 ieee80211_send_proberesp(vap, wh->i_addr2,
 917                     is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
 918
 919                 /*
 920                  * Note: we don't benefit from stashing the probe request
 921                  * IEs away to use for IBSS negotiation, because we
 922                  * typically don't get all of the IEs.
 923                  */
 924                 break;
 925
 926         case IEEE80211_FC0_SUBTYPE_ACTION:
 927         case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
 928                 if ((ni == vap->iv_bss) &&
 929                     !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
 930                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 931                             wh, NULL, "%s", "unknown node");
 932                         vap->iv_stats.is_rx_mgtdiscard++;
 933                 } else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
 934                     !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
 935                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 936                             wh, NULL, "%s", "not for us");
 937                         vap->iv_stats.is_rx_mgtdiscard++;
 938                 } else if (vap->iv_state != IEEE80211_S_RUN) {
 939                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 940                             wh, NULL, "wrong state %s",
 941                             ieee80211_state_name[vap->iv_state]);
 942                         vap->iv_stats.is_rx_mgtdiscard++;
 943                 } else {
 944                         if (ieee80211_parse_action(ni, m0) == 0)
 945                                 (void)ic->ic_recv_action(ni, wh, frm, efrm);
 946                 }
 947                 break;
 948
 949         case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
 950         case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
 951         case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
 952         case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
 953         case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
 954         case IEEE80211_FC0_SUBTYPE_ATIM:
 955         case IEEE80211_FC0_SUBTYPE_DISASSOC:
 956         case IEEE80211_FC0_SUBTYPE_AUTH:
 957         case IEEE80211_FC0_SUBTYPE_DEAUTH:
 958                 IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
 959                     wh, NULL, "%s", "not handled");
 960                 vap->iv_stats.is_rx_mgtdiscard++;
 961                 break;
 962
 963         default:
 964                 IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
 965                     wh, "mgt", "subtype 0x%x not handled", subtype);
 966                 vap->iv_stats.is_rx_badsubtype++;
 967                 break;
 968         }
 969 }
 970 #undef IEEE80211_VERIFY_LENGTH
 971 #undef IEEE80211_VERIFY_ELEMENT
 972
 973 static void
 974 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
 975         int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
 976 {
 977         struct ieee80211vap *vap = ni->ni_vap;
 978         struct ieee80211com *ic = ni->ni_ic;
 979         struct ieee80211_frame *wh;
 980
 981         /*
 982          * Process management frames when scanning; useful for doing
 983          * a site-survey.
 984          */
 985         if (ic->ic_flags & IEEE80211_F_SCAN)
 986                 adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
 987         else {
 988                 wh = mtod(m0, struct ieee80211_frame *);
 989                 switch (subtype) {
 990                 case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
 991                 case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
 992                 case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
 993                 case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
 994                 case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
 995                 case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
 996                 case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
 997                 case IEEE80211_FC0_SUBTYPE_BEACON:
 998                 case IEEE80211_FC0_SUBTYPE_ATIM:
 999                 case IEEE80211_FC0_SUBTYPE_DISASSOC:
1000                 case IEEE80211_FC0_SUBTYPE_AUTH:
1001                 case IEEE80211_FC0_SUBTYPE_DEAUTH:
1002                 case IEEE80211_FC0_SUBTYPE_ACTION:
1003                 case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
1004                         IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
1005                              wh, NULL, "%s", "not handled");
1006                         vap->iv_stats.is_rx_mgtdiscard++;
1007                         break;
1008                 default:
1009                         IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
1010                              wh, "mgt", "subtype 0x%x not handled", subtype);
1011                         vap->iv_stats.is_rx_badsubtype++;
1012                         break;
1013                 }
1014         }
1015 }
1016
1017 static void
1018 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
1019 {
1020
1021         switch (subtype) {
1022         case IEEE80211_FC0_SUBTYPE_BAR:
1023                 ieee80211_recv_bar(ni, m);
1024                 break;
1025         }
1026 }