The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/net80211/ieee80211_input.c

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    1 /*-
    2  * Copyright (c) 2001 Atsushi Onoe
    3  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
    4  * All rights reserved.
    5  *
    6  * Redistribution and use in source and binary forms, with or without
    7  * modification, are permitted provided that the following conditions
    8  * are met:
    9  * 1. Redistributions of source code must retain the above copyright
   10  *    notice, this list of conditions and the following disclaimer.
   11  * 2. Redistributions in binary form must reproduce the above copyright
   12  *    notice, this list of conditions and the following disclaimer in the
   13  *    documentation and/or other materials provided with the distribution.
   14  *
   15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   25  */
   26 
   27 #include <sys/cdefs.h>
   28 __FBSDID("$FreeBSD: releng/11.0/sys/net80211/ieee80211_input.c 300910 2016-05-28 18:49:17Z avos $");
   29 
   30 #include "opt_wlan.h"
   31 
   32 #include <sys/param.h>
   33 #include <sys/systm.h>
   34 #include <sys/mbuf.h>   
   35 #include <sys/malloc.h>
   36 #include <sys/endian.h>
   37 #include <sys/kernel.h>
   38  
   39 #include <sys/socket.h>
   40  
   41 #include <net/ethernet.h>
   42 #include <net/if.h>
   43 #include <net/if_var.h>
   44 #include <net/if_llc.h>
   45 #include <net/if_media.h>
   46 #include <net/if_vlan_var.h>
   47 
   48 #include <net80211/ieee80211_var.h>
   49 #include <net80211/ieee80211_input.h>
   50 #ifdef IEEE80211_SUPPORT_MESH
   51 #include <net80211/ieee80211_mesh.h>
   52 #endif
   53 
   54 #include <net/bpf.h>
   55 
   56 #ifdef INET
   57 #include <netinet/in.h>
   58 #include <net/ethernet.h>
   59 #endif
   60 
   61 static void
   62 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
   63 {
   64         int i;
   65 
   66         /* Verify the required MIMO bits are set */
   67         if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
   68             (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
   69                 return;
   70 
   71         /* XXX This assumes the MIMO radios have both ctl and ext chains */
   72         for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
   73                 IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
   74                 IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
   75         }
   76 
   77         /* XXX This also assumes the MIMO radios have both ctl and ext chains */
   78         for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
   79                 ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
   80                 ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
   81         }
   82         ni->ni_mimo_chains = rx->c_chain;
   83 }
   84 
   85 int
   86 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
   87     struct ieee80211_rx_stats *rx)
   88 {
   89         struct ieee80211_rx_stats rxs;
   90 
   91         if (rx) {
   92                 memcpy(&rxs, rx, sizeof(*rx));
   93         } else {
   94                 /* try to read from mbuf */
   95                 bzero(&rxs, sizeof(rxs));
   96                 ieee80211_get_rx_params(m, &rxs);
   97         }
   98 
   99         /* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
  100         ieee80211_process_mimo(ni, &rxs);
  101 
  102         //return ieee80211_input(ni, m, rx->rssi, rx->nf);
  103         return ni->ni_vap->iv_input(ni, m, &rxs, rxs.rssi, rxs.nf);
  104 }
  105 
  106 int
  107 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
  108 {
  109         struct ieee80211_rx_stats rx;
  110 
  111         rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
  112         rx.nf = nf;
  113         rx.rssi = rssi;
  114         return ieee80211_input_mimo_all(ic, m, &rx);
  115 }
  116 
  117 int
  118 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
  119     struct ieee80211_rx_stats *rx)
  120 {
  121         struct ieee80211_rx_stats rxs;
  122         struct ieee80211vap *vap;
  123         int type = -1;
  124 
  125         m->m_flags |= M_BCAST;          /* NB: mark for bpf tap'ing */
  126 
  127         if (rx) {
  128                 memcpy(&rxs, rx, sizeof(*rx));
  129         } else {
  130                 /* try to read from mbuf */
  131                 bzero(&rxs, sizeof(rxs));
  132                 ieee80211_get_rx_params(m, &rxs);
  133         }
  134 
  135         /* XXX locking */
  136         TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
  137                 struct ieee80211_node *ni;
  138                 struct mbuf *mcopy;
  139 
  140                 /* NB: could check for IFF_UP but this is cheaper */
  141                 if (vap->iv_state == IEEE80211_S_INIT)
  142                         continue;
  143                 /*
  144                  * WDS vap's only receive directed traffic from the
  145                  * station at the ``far end''.  That traffic should
  146                  * be passed through the AP vap the station is associated
  147                  * to--so don't spam them with mcast frames.
  148                  */
  149                 if (vap->iv_opmode == IEEE80211_M_WDS)
  150                         continue;
  151                 if (TAILQ_NEXT(vap, iv_next) != NULL) {
  152                         /*
  153                          * Packet contents are changed by ieee80211_decap
  154                          * so do a deep copy of the packet.
  155                          */
  156                         mcopy = m_dup(m, M_NOWAIT);
  157                         if (mcopy == NULL) {
  158                                 /* XXX stat+msg */
  159                                 continue;
  160                         }
  161                 } else {
  162                         mcopy = m;
  163                         m = NULL;
  164                 }
  165                 ni = ieee80211_ref_node(vap->iv_bss);
  166                 type = ieee80211_input_mimo(ni, mcopy, &rxs);
  167                 ieee80211_free_node(ni);
  168         }
  169         if (m != NULL)                  /* no vaps, reclaim mbuf */
  170                 m_freem(m);
  171         return type;
  172 }
  173 
  174 /*
  175  * This function reassembles fragments.
  176  *
  177  * XXX should handle 3 concurrent reassemblies per-spec.
  178  */
  179 struct mbuf *
  180 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
  181 {
  182         struct ieee80211vap *vap = ni->ni_vap;
  183         struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
  184         struct ieee80211_frame *lwh;
  185         uint16_t rxseq;
  186         uint8_t fragno;
  187         uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
  188         struct mbuf *mfrag;
  189 
  190         KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
  191 
  192         rxseq = le16toh(*(uint16_t *)wh->i_seq);
  193         fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
  194 
  195         /* Quick way out, if there's nothing to defragment */
  196         if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
  197                 return m;
  198 
  199         /*
  200          * Remove frag to insure it doesn't get reaped by timer.
  201          */
  202         if (ni->ni_table == NULL) {
  203                 /*
  204                  * Should never happen.  If the node is orphaned (not in
  205                  * the table) then input packets should not reach here.
  206                  * Otherwise, a concurrent request that yanks the table
  207                  * should be blocked by other interlocking and/or by first
  208                  * shutting the driver down.  Regardless, be defensive
  209                  * here and just bail
  210                  */
  211                 /* XXX need msg+stat */
  212                 m_freem(m);
  213                 return NULL;
  214         }
  215         IEEE80211_NODE_LOCK(ni->ni_table);
  216         mfrag = ni->ni_rxfrag[0];
  217         ni->ni_rxfrag[0] = NULL;
  218         IEEE80211_NODE_UNLOCK(ni->ni_table);
  219 
  220         /*
  221          * Validate new fragment is in order and
  222          * related to the previous ones.
  223          */
  224         if (mfrag != NULL) {
  225                 uint16_t last_rxseq;
  226 
  227                 lwh = mtod(mfrag, struct ieee80211_frame *);
  228                 last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
  229                 /* NB: check seq # and frag together */
  230                 if (rxseq == last_rxseq+1 &&
  231                     IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) &&
  232                     IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
  233                         /* XXX clear MORE_FRAG bit? */
  234                         /* track last seqnum and fragno */
  235                         *(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
  236 
  237                         m_adj(m, hdrspace);             /* strip header */
  238                         m_catpkt(mfrag, m);             /* concatenate */
  239                 } else {
  240                         /*
  241                          * Unrelated fragment or no space for it,
  242                          * clear current fragments.
  243                          */
  244                         m_freem(mfrag);
  245                         mfrag = NULL;
  246                 }
  247         }
  248 
  249         if (mfrag == NULL) {
  250                 if (fragno != 0) {              /* !first fragment, discard */
  251                         vap->iv_stats.is_rx_defrag++;
  252                         IEEE80211_NODE_STAT(ni, rx_defrag);
  253                         m_freem(m);
  254                         return NULL;
  255                 }
  256                 mfrag = m;
  257         }
  258         if (more_frag) {                        /* more to come, save */
  259                 ni->ni_rxfragstamp = ticks;
  260                 ni->ni_rxfrag[0] = mfrag;
  261                 mfrag = NULL;
  262         }
  263         return mfrag;
  264 }
  265 
  266 void
  267 ieee80211_deliver_data(struct ieee80211vap *vap,
  268         struct ieee80211_node *ni, struct mbuf *m)
  269 {
  270         struct ether_header *eh = mtod(m, struct ether_header *);
  271         struct ifnet *ifp = vap->iv_ifp;
  272 
  273         /* clear driver/net80211 flags before passing up */
  274         m->m_flags &= ~(M_MCAST | M_BCAST);
  275         m_clrprotoflags(m);
  276 
  277         /* NB: see hostap_deliver_data, this path doesn't handle hostap */
  278         KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
  279         /*
  280          * Do accounting.
  281          */
  282         if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
  283         IEEE80211_NODE_STAT(ni, rx_data);
  284         IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
  285         if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
  286                 m->m_flags |= M_MCAST;          /* XXX M_BCAST? */
  287                 IEEE80211_NODE_STAT(ni, rx_mcast);
  288         } else
  289                 IEEE80211_NODE_STAT(ni, rx_ucast);
  290         m->m_pkthdr.rcvif = ifp;
  291 
  292         if (ni->ni_vlan != 0) {
  293                 /* attach vlan tag */
  294                 m->m_pkthdr.ether_vtag = ni->ni_vlan;
  295                 m->m_flags |= M_VLANTAG;
  296         }
  297         ifp->if_input(ifp, m);
  298 }
  299 
  300 struct mbuf *
  301 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
  302 {
  303         struct ieee80211_qosframe_addr4 wh;
  304         struct ether_header *eh;
  305         struct llc *llc;
  306 
  307         KASSERT(hdrlen <= sizeof(wh),
  308             ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
  309 
  310         if (m->m_len < hdrlen + sizeof(*llc) &&
  311             (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
  312                 vap->iv_stats.is_rx_tooshort++;
  313                 /* XXX msg */
  314                 return NULL;
  315         }
  316         memcpy(&wh, mtod(m, caddr_t), hdrlen);
  317         llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
  318         if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
  319             llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
  320             llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
  321             /* NB: preserve AppleTalk frames that have a native SNAP hdr */
  322             !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
  323               llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
  324                 m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
  325                 llc = NULL;
  326         } else {
  327                 m_adj(m, hdrlen - sizeof(*eh));
  328         }
  329         eh = mtod(m, struct ether_header *);
  330         switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
  331         case IEEE80211_FC1_DIR_NODS:
  332                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
  333                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
  334                 break;
  335         case IEEE80211_FC1_DIR_TODS:
  336                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
  337                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
  338                 break;
  339         case IEEE80211_FC1_DIR_FROMDS:
  340                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
  341                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
  342                 break;
  343         case IEEE80211_FC1_DIR_DSTODS:
  344                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
  345                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
  346                 break;
  347         }
  348 #ifndef __NO_STRICT_ALIGNMENT
  349         if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
  350                 m = ieee80211_realign(vap, m, sizeof(*eh));
  351                 if (m == NULL)
  352                         return NULL;
  353         }
  354 #endif /* !__NO_STRICT_ALIGNMENT */
  355         if (llc != NULL) {
  356                 eh = mtod(m, struct ether_header *);
  357                 eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
  358         }
  359         return m;
  360 }
  361 
  362 /*
  363  * Decap a frame encapsulated in a fast-frame/A-MSDU.
  364  */
  365 struct mbuf *
  366 ieee80211_decap1(struct mbuf *m, int *framelen)
  367 {
  368 #define FF_LLC_SIZE     (sizeof(struct ether_header) + sizeof(struct llc))
  369         struct ether_header *eh;
  370         struct llc *llc;
  371 
  372         /*
  373          * The frame has an 802.3 header followed by an 802.2
  374          * LLC header.  The encapsulated frame length is in the
  375          * first header type field; save that and overwrite it 
  376          * with the true type field found in the second.  Then
  377          * copy the 802.3 header up to where it belongs and
  378          * adjust the mbuf contents to remove the void.
  379          */
  380         if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
  381                 return NULL;
  382         eh = mtod(m, struct ether_header *);    /* 802.3 header is first */
  383         llc = (struct llc *)&eh[1];             /* 802.2 header follows */
  384         *framelen = ntohs(eh->ether_type)       /* encap'd frame size */
  385                   + sizeof(struct ether_header) - sizeof(struct llc);
  386         eh->ether_type = llc->llc_un.type_snap.ether_type;
  387         ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
  388                 sizeof(struct ether_header));
  389         m_adj(m, sizeof(struct llc));
  390         return m;
  391 #undef FF_LLC_SIZE
  392 }
  393 
  394 /*
  395  * Install received rate set information in the node's state block.
  396  */
  397 int
  398 ieee80211_setup_rates(struct ieee80211_node *ni,
  399         const uint8_t *rates, const uint8_t *xrates, int flags)
  400 {
  401         struct ieee80211vap *vap = ni->ni_vap;
  402         struct ieee80211_rateset *rs = &ni->ni_rates;
  403 
  404         memset(rs, 0, sizeof(*rs));
  405         rs->rs_nrates = rates[1];
  406         memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
  407         if (xrates != NULL) {
  408                 uint8_t nxrates;
  409                 /*
  410                  * Tack on 11g extended supported rate element.
  411                  */
  412                 nxrates = xrates[1];
  413                 if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
  414                         nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
  415                         IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
  416                             "extended rate set too large; only using "
  417                             "%u of %u rates", nxrates, xrates[1]);
  418                         vap->iv_stats.is_rx_rstoobig++;
  419                 }
  420                 memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
  421                 rs->rs_nrates += nxrates;
  422         }
  423         return ieee80211_fix_rate(ni, rs, flags);
  424 }
  425 
  426 /*
  427  * Send a management frame error response to the specified
  428  * station.  If ni is associated with the station then use
  429  * it; otherwise allocate a temporary node suitable for
  430  * transmitting the frame and then free the reference so
  431  * it will go away as soon as the frame has been transmitted.
  432  */
  433 void
  434 ieee80211_send_error(struct ieee80211_node *ni,
  435         const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
  436 {
  437         struct ieee80211vap *vap = ni->ni_vap;
  438         int istmp;
  439 
  440         if (ni == vap->iv_bss) {
  441                 if (vap->iv_state != IEEE80211_S_RUN) {
  442                         /*
  443                          * XXX hack until we get rid of this routine.
  444                          * We can be called prior to the vap reaching
  445                          * run state under certain conditions in which
  446                          * case iv_bss->ni_chan will not be setup.
  447                          * Check for this explicitly and and just ignore
  448                          * the request.
  449                          */
  450                         return;
  451                 }
  452                 ni = ieee80211_tmp_node(vap, mac);
  453                 if (ni == NULL) {
  454                         /* XXX msg */
  455                         return;
  456                 }
  457                 istmp = 1;
  458         } else
  459                 istmp = 0;
  460         IEEE80211_SEND_MGMT(ni, subtype, arg);
  461         if (istmp)
  462                 ieee80211_free_node(ni);
  463 }
  464 
  465 int
  466 ieee80211_alloc_challenge(struct ieee80211_node *ni)
  467 {
  468         if (ni->ni_challenge == NULL)
  469                 ni->ni_challenge = (uint32_t *)
  470                     IEEE80211_MALLOC(IEEE80211_CHALLENGE_LEN,
  471                       M_80211_NODE, IEEE80211_M_NOWAIT);
  472         if (ni->ni_challenge == NULL) {
  473                 IEEE80211_NOTE(ni->ni_vap,
  474                     IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
  475                     "%s", "shared key challenge alloc failed");
  476                 /* XXX statistic */
  477         }
  478         return (ni->ni_challenge != NULL);
  479 }
  480 
  481 /*
  482  * Parse a Beacon or ProbeResponse frame and return the
  483  * useful information in an ieee80211_scanparams structure.
  484  * Status is set to 0 if no problems were found; otherwise
  485  * a bitmask of IEEE80211_BPARSE_* items is returned that
  486  * describes the problems detected.
  487  */
  488 int
  489 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
  490         struct ieee80211_channel *rxchan, struct ieee80211_scanparams *scan)
  491 {
  492         struct ieee80211vap *vap = ni->ni_vap;
  493         struct ieee80211com *ic = ni->ni_ic;
  494         struct ieee80211_frame *wh;
  495         uint8_t *frm, *efrm;
  496 
  497         wh = mtod(m, struct ieee80211_frame *);
  498         frm = (uint8_t *)&wh[1];
  499         efrm = mtod(m, uint8_t *) + m->m_len;
  500         scan->status = 0;
  501         /*
  502          * beacon/probe response frame format
  503          *      [8] time stamp
  504          *      [2] beacon interval
  505          *      [2] capability information
  506          *      [tlv] ssid
  507          *      [tlv] supported rates
  508          *      [tlv] country information
  509          *      [tlv] channel switch announcement (CSA)
  510          *      [tlv] parameter set (FH/DS)
  511          *      [tlv] erp information
  512          *      [tlv] extended supported rates
  513          *      [tlv] WME
  514          *      [tlv] WPA or RSN
  515          *      [tlv] HT capabilities
  516          *      [tlv] HT information
  517          *      [tlv] Atheros capabilities
  518          *      [tlv] Mesh ID
  519          *      [tlv] Mesh Configuration
  520          */
  521         IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
  522             return (scan->status = IEEE80211_BPARSE_BADIELEN));
  523         memset(scan, 0, sizeof(*scan));
  524         scan->tstamp  = frm;                            frm += 8;
  525         scan->bintval = le16toh(*(uint16_t *)frm);      frm += 2;
  526         scan->capinfo = le16toh(*(uint16_t *)frm);      frm += 2;
  527         scan->bchan = ieee80211_chan2ieee(ic, rxchan);
  528         scan->chan = scan->bchan;
  529         scan->ies = frm;
  530         scan->ies_len = efrm - frm;
  531 
  532         while (efrm - frm > 1) {
  533                 IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
  534                     return (scan->status = IEEE80211_BPARSE_BADIELEN));
  535                 switch (*frm) {
  536                 case IEEE80211_ELEMID_SSID:
  537                         scan->ssid = frm;
  538                         break;
  539                 case IEEE80211_ELEMID_RATES:
  540                         scan->rates = frm;
  541                         break;
  542                 case IEEE80211_ELEMID_COUNTRY:
  543                         scan->country = frm;
  544                         break;
  545                 case IEEE80211_ELEMID_CSA:
  546                         scan->csa = frm;
  547                         break;
  548                 case IEEE80211_ELEMID_QUIET:
  549                         scan->quiet = frm;
  550                         break;
  551                 case IEEE80211_ELEMID_FHPARMS:
  552                         if (ic->ic_phytype == IEEE80211_T_FH) {
  553                                 scan->fhdwell = le16dec(&frm[2]);
  554                                 scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
  555                                 scan->fhindex = frm[6];
  556                         }
  557                         break;
  558                 case IEEE80211_ELEMID_DSPARMS:
  559                         /*
  560                          * XXX hack this since depending on phytype
  561                          * is problematic for multi-mode devices.
  562                          */
  563                         if (ic->ic_phytype != IEEE80211_T_FH)
  564                                 scan->chan = frm[2];
  565                         break;
  566                 case IEEE80211_ELEMID_TIM:
  567                         /* XXX ATIM? */
  568                         scan->tim = frm;
  569                         scan->timoff = frm - mtod(m, uint8_t *);
  570                         break;
  571                 case IEEE80211_ELEMID_IBSSPARMS:
  572                 case IEEE80211_ELEMID_CFPARMS:
  573                 case IEEE80211_ELEMID_PWRCNSTR:
  574                 case IEEE80211_ELEMID_BSSLOAD:
  575                 case IEEE80211_ELEMID_APCHANREP:
  576                         /* NB: avoid debugging complaints */
  577                         break;
  578                 case IEEE80211_ELEMID_XRATES:
  579                         scan->xrates = frm;
  580                         break;
  581                 case IEEE80211_ELEMID_ERP:
  582                         if (frm[1] != 1) {
  583                                 IEEE80211_DISCARD_IE(vap,
  584                                     IEEE80211_MSG_ELEMID, wh, "ERP",
  585                                     "bad len %u", frm[1]);
  586                                 vap->iv_stats.is_rx_elem_toobig++;
  587                                 break;
  588                         }
  589                         scan->erp = frm[2] | 0x100;
  590                         break;
  591                 case IEEE80211_ELEMID_HTCAP:
  592                         scan->htcap = frm;
  593                         break;
  594                 case IEEE80211_ELEMID_RSN:
  595                         scan->rsn = frm;
  596                         break;
  597                 case IEEE80211_ELEMID_HTINFO:
  598                         scan->htinfo = frm;
  599                         break;
  600 #ifdef IEEE80211_SUPPORT_MESH
  601                 case IEEE80211_ELEMID_MESHID:
  602                         scan->meshid = frm;
  603                         break;
  604                 case IEEE80211_ELEMID_MESHCONF:
  605                         scan->meshconf = frm;
  606                         break;
  607 #endif
  608                 /* Extended capabilities; nothing handles it for now */
  609                 case IEEE80211_ELEMID_EXTCAP:
  610                         break;
  611                 case IEEE80211_ELEMID_VENDOR:
  612                         if (iswpaoui(frm))
  613                                 scan->wpa = frm;
  614                         else if (iswmeparam(frm) || iswmeinfo(frm))
  615                                 scan->wme = frm;
  616 #ifdef IEEE80211_SUPPORT_SUPERG
  617                         else if (isatherosoui(frm))
  618                                 scan->ath = frm;
  619 #endif
  620 #ifdef IEEE80211_SUPPORT_TDMA
  621                         else if (istdmaoui(frm))
  622                                 scan->tdma = frm;
  623 #endif
  624                         else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
  625                                 /*
  626                                  * Accept pre-draft HT ie's if the
  627                                  * standard ones have not been seen.
  628                                  */
  629                                 if (ishtcapoui(frm)) {
  630                                         if (scan->htcap == NULL)
  631                                                 scan->htcap = frm;
  632                                 } else if (ishtinfooui(frm)) {
  633                                         if (scan->htinfo == NULL)
  634                                                 scan->htcap = frm;
  635                                 }
  636                         }
  637                         break;
  638                 default:
  639                         IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
  640                             wh, "unhandled",
  641                             "id %u, len %u", *frm, frm[1]);
  642                         vap->iv_stats.is_rx_elem_unknown++;
  643                         break;
  644                 }
  645                 frm += frm[1] + 2;
  646         }
  647         IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
  648             scan->status |= IEEE80211_BPARSE_RATES_INVALID);
  649         if (scan->rates != NULL && scan->xrates != NULL) {
  650                 /*
  651                  * NB: don't process XRATES if RATES is missing.  This
  652                  * avoids a potential null ptr deref and should be ok
  653                  * as the return code will already note RATES is missing
  654                  * (so callers shouldn't otherwise process the frame).
  655                  */
  656                 IEEE80211_VERIFY_ELEMENT(scan->xrates,
  657                     IEEE80211_RATE_MAXSIZE - scan->rates[1],
  658                     scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
  659         }
  660         IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
  661             scan->status |= IEEE80211_BPARSE_SSID_INVALID);
  662         if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
  663                 /*
  664                  * Frame was received on a channel different from the
  665                  * one indicated in the DS params element id;
  666                  * silently discard it.
  667                  *
  668                  * NB: this can happen due to signal leakage.
  669                  *     But we should take it for FH phy because
  670                  *     the rssi value should be correct even for
  671                  *     different hop pattern in FH.
  672                  */
  673                 IEEE80211_DISCARD(vap,
  674                     IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
  675                     wh, NULL, "for off-channel %u (bchan=%u)",
  676                     scan->chan, scan->bchan);
  677                 vap->iv_stats.is_rx_chanmismatch++;
  678                 scan->status |= IEEE80211_BPARSE_OFFCHAN;
  679         }
  680         if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
  681               scan->bintval <= IEEE80211_BINTVAL_MAX)) {
  682                 IEEE80211_DISCARD(vap,
  683                     IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
  684                     wh, NULL, "bogus beacon interval (%d TU)",
  685                     (int) scan->bintval);
  686                 vap->iv_stats.is_rx_badbintval++;
  687                 scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
  688         }
  689         if (scan->country != NULL) {
  690                 /*
  691                  * Validate we have at least enough data to extract
  692                  * the country code.  Not sure if we should return an
  693                  * error instead of discarding the IE; consider this
  694                  * being lenient as we don't depend on the data for
  695                  * correct operation.
  696                  */
  697                 IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
  698                     scan->country = NULL);
  699         }
  700         if (scan->csa != NULL) {
  701                 /*
  702                  * Validate Channel Switch Announcement; this must
  703                  * be the correct length or we toss the frame.
  704                  */
  705                 IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
  706                     scan->status |= IEEE80211_BPARSE_CSA_INVALID);
  707         }
  708         /*
  709          * Process HT ie's.  This is complicated by our
  710          * accepting both the standard ie's and the pre-draft
  711          * vendor OUI ie's that some vendors still use/require.
  712          */
  713         if (scan->htcap != NULL) {
  714                 IEEE80211_VERIFY_LENGTH(scan->htcap[1],
  715                      scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
  716                          4 + sizeof(struct ieee80211_ie_htcap)-2 :
  717                          sizeof(struct ieee80211_ie_htcap)-2,
  718                      scan->htcap = NULL);
  719         }
  720         if (scan->htinfo != NULL) {
  721                 IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
  722                      scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
  723                          4 + sizeof(struct ieee80211_ie_htinfo)-2 :
  724                          sizeof(struct ieee80211_ie_htinfo)-2,
  725                      scan->htinfo = NULL);
  726         }
  727         return scan->status;
  728 }
  729 
  730 /*
  731  * Parse an Action frame.  Return 0 on success, non-zero on failure.
  732  */
  733 int
  734 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
  735 {
  736         struct ieee80211vap *vap = ni->ni_vap;
  737         const struct ieee80211_action *ia;
  738         struct ieee80211_frame *wh;
  739         uint8_t *frm, *efrm;
  740 
  741         /*
  742          * action frame format:
  743          *      [1] category
  744          *      [1] action
  745          *      [tlv] parameters
  746          */
  747         wh = mtod(m, struct ieee80211_frame *);
  748         frm = (u_int8_t *)&wh[1];
  749         efrm = mtod(m, u_int8_t *) + m->m_len;
  750         IEEE80211_VERIFY_LENGTH(efrm - frm,
  751                 sizeof(struct ieee80211_action), return EINVAL);
  752         ia = (const struct ieee80211_action *) frm;
  753 
  754         vap->iv_stats.is_rx_action++;
  755         IEEE80211_NODE_STAT(ni, rx_action);
  756 
  757         /* verify frame payloads but defer processing */
  758         switch (ia->ia_category) {
  759         case IEEE80211_ACTION_CAT_BA:
  760                 switch (ia->ia_action) {
  761                 case IEEE80211_ACTION_BA_ADDBA_REQUEST:
  762                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  763                             sizeof(struct ieee80211_action_ba_addbarequest),
  764                             return EINVAL);
  765                         break;
  766                 case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
  767                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  768                             sizeof(struct ieee80211_action_ba_addbaresponse),
  769                             return EINVAL);
  770                         break;
  771                 case IEEE80211_ACTION_BA_DELBA:
  772                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  773                             sizeof(struct ieee80211_action_ba_delba),
  774                             return EINVAL);
  775                         break;
  776                 }
  777                 break;
  778         case IEEE80211_ACTION_CAT_HT:
  779                 switch (ia->ia_action) {
  780                 case IEEE80211_ACTION_HT_TXCHWIDTH:
  781                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  782                             sizeof(struct ieee80211_action_ht_txchwidth),
  783                             return EINVAL);
  784                         break;
  785                 case IEEE80211_ACTION_HT_MIMOPWRSAVE:
  786                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  787                             sizeof(struct ieee80211_action_ht_mimopowersave),
  788                             return EINVAL);
  789                         break;
  790                 }
  791                 break;
  792 #ifdef IEEE80211_SUPPORT_MESH
  793         case IEEE80211_ACTION_CAT_MESH:
  794                 switch (ia->ia_action) {
  795                 case IEEE80211_ACTION_MESH_LMETRIC:
  796                         /*
  797                          * XXX: verification is true only if we are using
  798                          * Airtime link metric (default)
  799                          */
  800                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  801                             sizeof(struct ieee80211_meshlmetric_ie),
  802                             return EINVAL);
  803                         break;
  804                 case IEEE80211_ACTION_MESH_HWMP:
  805                         /* verify something */
  806                         break;
  807                 case IEEE80211_ACTION_MESH_GANN:
  808                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  809                             sizeof(struct ieee80211_meshgann_ie),
  810                             return EINVAL);
  811                         break;
  812                 case IEEE80211_ACTION_MESH_CC:
  813                 case IEEE80211_ACTION_MESH_MCCA_SREQ:
  814                 case IEEE80211_ACTION_MESH_MCCA_SREP:
  815                 case IEEE80211_ACTION_MESH_MCCA_AREQ:
  816                 case IEEE80211_ACTION_MESH_MCCA_ADVER:
  817                 case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
  818                 case IEEE80211_ACTION_MESH_TBTT_REQ:
  819                 case IEEE80211_ACTION_MESH_TBTT_RES:
  820                         /* reject these early on, not implemented */
  821                         IEEE80211_DISCARD(vap,
  822                             IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
  823                             wh, NULL, "not implemented yet, act=0x%02X",
  824                             ia->ia_action);
  825                         return EINVAL;
  826                 }
  827                 break;
  828         case IEEE80211_ACTION_CAT_SELF_PROT:
  829                 /* If TA or RA group address discard silently */
  830                 if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
  831                         IEEE80211_IS_MULTICAST(wh->i_addr2))
  832                         return EINVAL;
  833                 /*
  834                  * XXX: Should we verify complete length now or it is
  835                  * to varying in sizes?
  836                  */
  837                 switch (ia->ia_action) {
  838                 case IEEE80211_ACTION_MESHPEERING_CONFIRM:
  839                 case IEEE80211_ACTION_MESHPEERING_CLOSE:
  840                         /* is not a peering candidate (yet) */
  841                         if (ni == vap->iv_bss)
  842                                 return EINVAL;
  843                         break;
  844                 }
  845                 break;
  846 #endif
  847         }
  848         return 0;
  849 }
  850 
  851 #ifdef IEEE80211_DEBUG
  852 /*
  853  * Debugging support.
  854  */
  855 void
  856 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
  857         uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
  858 {
  859         printf("[%s] discard %s frame, ssid mismatch: ",
  860                 ether_sprintf(mac), tag);
  861         ieee80211_print_essid(ssid + 2, ssid[1]);
  862         printf("\n");
  863 }
  864 
  865 /*
  866  * Return the bssid of a frame.
  867  */
  868 static const uint8_t *
  869 ieee80211_getbssid(const struct ieee80211vap *vap,
  870         const struct ieee80211_frame *wh)
  871 {
  872         if (vap->iv_opmode == IEEE80211_M_STA)
  873                 return wh->i_addr2;
  874         if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
  875                 return wh->i_addr1;
  876         if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
  877                 return wh->i_addr1;
  878         return wh->i_addr3;
  879 }
  880 
  881 #include <machine/stdarg.h>
  882 
  883 void
  884 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
  885 {
  886         char buf[128];          /* XXX */
  887         va_list ap;
  888 
  889         va_start(ap, fmt);
  890         vsnprintf(buf, sizeof(buf), fmt, ap);
  891         va_end(ap);
  892 
  893         if_printf(vap->iv_ifp, "%s", buf);      /* NB: no \n */
  894 }
  895 
  896 void
  897 ieee80211_note_frame(const struct ieee80211vap *vap,
  898         const struct ieee80211_frame *wh,
  899         const char *fmt, ...)
  900 {
  901         char buf[128];          /* XXX */
  902         va_list ap;
  903 
  904         va_start(ap, fmt);
  905         vsnprintf(buf, sizeof(buf), fmt, ap);
  906         va_end(ap);
  907         if_printf(vap->iv_ifp, "[%s] %s\n",
  908                 ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
  909 }
  910 
  911 void
  912 ieee80211_note_mac(const struct ieee80211vap *vap,
  913         const uint8_t mac[IEEE80211_ADDR_LEN],
  914         const char *fmt, ...)
  915 {
  916         char buf[128];          /* XXX */
  917         va_list ap;
  918 
  919         va_start(ap, fmt);
  920         vsnprintf(buf, sizeof(buf), fmt, ap);
  921         va_end(ap);
  922         if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
  923 }
  924 
  925 void
  926 ieee80211_discard_frame(const struct ieee80211vap *vap,
  927         const struct ieee80211_frame *wh,
  928         const char *type, const char *fmt, ...)
  929 {
  930         va_list ap;
  931 
  932         if_printf(vap->iv_ifp, "[%s] discard ",
  933                 ether_sprintf(ieee80211_getbssid(vap, wh)));
  934         printf("%s frame, ", type != NULL ? type :
  935             ieee80211_mgt_subtype_name(wh->i_fc[0]));
  936         va_start(ap, fmt);
  937         vprintf(fmt, ap);
  938         va_end(ap);
  939         printf("\n");
  940 }
  941 
  942 void
  943 ieee80211_discard_ie(const struct ieee80211vap *vap,
  944         const struct ieee80211_frame *wh,
  945         const char *type, const char *fmt, ...)
  946 {
  947         va_list ap;
  948 
  949         if_printf(vap->iv_ifp, "[%s] discard ",
  950                 ether_sprintf(ieee80211_getbssid(vap, wh)));
  951         if (type != NULL)
  952                 printf("%s information element, ", type);
  953         else
  954                 printf("information element, ");
  955         va_start(ap, fmt);
  956         vprintf(fmt, ap);
  957         va_end(ap);
  958         printf("\n");
  959 }
  960 
  961 void
  962 ieee80211_discard_mac(const struct ieee80211vap *vap,
  963         const uint8_t mac[IEEE80211_ADDR_LEN],
  964         const char *type, const char *fmt, ...)
  965 {
  966         va_list ap;
  967 
  968         if_printf(vap->iv_ifp, "[%s] discard ", ether_sprintf(mac));
  969         if (type != NULL)
  970                 printf("%s frame, ", type);
  971         else
  972                 printf("frame, ");
  973         va_start(ap, fmt);
  974         vprintf(fmt, ap);
  975         va_end(ap);
  976         printf("\n");
  977 }
  978 #endif /* IEEE80211_DEBUG */

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