The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/net80211/ieee80211_input.c

Version: -  FREEBSD  -  FREEBSD11  -  FREEBSD10  -  FREEBSD9  -  FREEBSD92  -  FREEBSD91  -  FREEBSD90  -  FREEBSD8  -  FREEBSD82  -  FREEBSD81  -  FREEBSD80  -  FREEBSD7  -  FREEBSD74  -  FREEBSD73  -  FREEBSD72  -  FREEBSD71  -  FREEBSD70  -  FREEBSD6  -  FREEBSD64  -  FREEBSD63  -  FREEBSD62  -  FREEBSD61  -  FREEBSD60  -  FREEBSD5  -  FREEBSD55  -  FREEBSD54  -  FREEBSD53  -  FREEBSD52  -  FREEBSD51  -  FREEBSD50  -  FREEBSD4  -  FREEBSD3  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    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: stable/9/sys/net80211/ieee80211_input.c 220445 2011-04-08 09:20:45Z adrian $");
   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_llc.h>
   44 #include <net/if_media.h>
   45 #include <net/if_vlan_var.h>
   46 
   47 #include <net80211/ieee80211_var.h>
   48 #include <net80211/ieee80211_input.h>
   49 #ifdef IEEE80211_SUPPORT_MESH
   50 #include <net80211/ieee80211_mesh.h>
   51 #endif
   52 
   53 #include <net/bpf.h>
   54 
   55 #ifdef INET
   56 #include <netinet/in.h>
   57 #include <net/ethernet.h>
   58 #endif
   59 
   60 static void
   61 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
   62 {
   63         int i;
   64 
   65         /* Verify the required MIMO bits are set */
   66         if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
   67             (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
   68                 return;
   69 
   70         /* XXX This assumes the MIMO radios have both ctl and ext chains */
   71         for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
   72                 IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
   73                 IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
   74         }
   75 
   76         /* XXX This also assumes the MIMO radios have both ctl and ext chains */
   77         for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
   78                 ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
   79                 ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
   80         }
   81         ni->ni_mimo_chains = rx->c_chain;
   82 }
   83 
   84 int
   85 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
   86     struct ieee80211_rx_stats *rx)
   87 {
   88         /* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
   89         ieee80211_process_mimo(ni, rx);
   90         return ieee80211_input(ni, m, rx->rssi, rx->nf);
   91 }
   92 
   93 int
   94 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
   95 {
   96         struct ieee80211_rx_stats rx;
   97 
   98         rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
   99         rx.nf = nf;
  100         rx.rssi = rssi;
  101         return ieee80211_input_mimo_all(ic, m, &rx);
  102 }
  103 
  104 int
  105 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
  106     struct ieee80211_rx_stats *rx)
  107 {
  108         struct ieee80211vap *vap;
  109         int type = -1;
  110 
  111         m->m_flags |= M_BCAST;          /* NB: mark for bpf tap'ing */
  112 
  113         /* XXX locking */
  114         TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
  115                 struct ieee80211_node *ni;
  116                 struct mbuf *mcopy;
  117 
  118                 /* NB: could check for IFF_UP but this is cheaper */
  119                 if (vap->iv_state == IEEE80211_S_INIT)
  120                         continue;
  121                 /*
  122                  * WDS vap's only receive directed traffic from the
  123                  * station at the ``far end''.  That traffic should
  124                  * be passed through the AP vap the station is associated
  125                  * to--so don't spam them with mcast frames.
  126                  */
  127                 if (vap->iv_opmode == IEEE80211_M_WDS)
  128                         continue;
  129                 if (TAILQ_NEXT(vap, iv_next) != NULL) {
  130                         /*
  131                          * Packet contents are changed by ieee80211_decap
  132                          * so do a deep copy of the packet.
  133                          */
  134                         mcopy = m_dup(m, M_DONTWAIT);
  135                         if (mcopy == NULL) {
  136                                 /* XXX stat+msg */
  137                                 continue;
  138                         }
  139                 } else {
  140                         mcopy = m;
  141                         m = NULL;
  142                 }
  143                 ni = ieee80211_ref_node(vap->iv_bss);
  144                 type = ieee80211_input_mimo(ni, mcopy, rx);
  145                 ieee80211_free_node(ni);
  146         }
  147         if (m != NULL)                  /* no vaps, reclaim mbuf */
  148                 m_freem(m);
  149         return type;
  150 }
  151 
  152 /*
  153  * This function reassembles fragments.
  154  *
  155  * XXX should handle 3 concurrent reassemblies per-spec.
  156  */
  157 struct mbuf *
  158 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
  159 {
  160         struct ieee80211vap *vap = ni->ni_vap;
  161         struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
  162         struct ieee80211_frame *lwh;
  163         uint16_t rxseq;
  164         uint8_t fragno;
  165         uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
  166         struct mbuf *mfrag;
  167 
  168         KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
  169 
  170         rxseq = le16toh(*(uint16_t *)wh->i_seq);
  171         fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
  172 
  173         /* Quick way out, if there's nothing to defragment */
  174         if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
  175                 return m;
  176 
  177         /*
  178          * Remove frag to insure it doesn't get reaped by timer.
  179          */
  180         if (ni->ni_table == NULL) {
  181                 /*
  182                  * Should never happen.  If the node is orphaned (not in
  183                  * the table) then input packets should not reach here.
  184                  * Otherwise, a concurrent request that yanks the table
  185                  * should be blocked by other interlocking and/or by first
  186                  * shutting the driver down.  Regardless, be defensive
  187                  * here and just bail
  188                  */
  189                 /* XXX need msg+stat */
  190                 m_freem(m);
  191                 return NULL;
  192         }
  193         IEEE80211_NODE_LOCK(ni->ni_table);
  194         mfrag = ni->ni_rxfrag[0];
  195         ni->ni_rxfrag[0] = NULL;
  196         IEEE80211_NODE_UNLOCK(ni->ni_table);
  197 
  198         /*
  199          * Validate new fragment is in order and
  200          * related to the previous ones.
  201          */
  202         if (mfrag != NULL) {
  203                 uint16_t last_rxseq;
  204 
  205                 lwh = mtod(mfrag, struct ieee80211_frame *);
  206                 last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
  207                 /* NB: check seq # and frag together */
  208                 if (rxseq != last_rxseq+1 ||
  209                     !IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) ||
  210                     !IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
  211                         /*
  212                          * Unrelated fragment or no space for it,
  213                          * clear current fragments.
  214                          */
  215                         m_freem(mfrag);
  216                         mfrag = NULL;
  217                 }
  218         }
  219 
  220         if (mfrag == NULL) {
  221                 if (fragno != 0) {              /* !first fragment, discard */
  222                         vap->iv_stats.is_rx_defrag++;
  223                         IEEE80211_NODE_STAT(ni, rx_defrag);
  224                         m_freem(m);
  225                         return NULL;
  226                 }
  227                 mfrag = m;
  228         } else {                                /* concatenate */
  229                 m_adj(m, hdrspace);             /* strip header */
  230                 m_cat(mfrag, m);
  231                 /* NB: m_cat doesn't update the packet header */
  232                 mfrag->m_pkthdr.len += m->m_pkthdr.len;
  233                 /* track last seqnum and fragno */
  234                 lwh = mtod(mfrag, struct ieee80211_frame *);
  235                 *(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
  236         }
  237         if (more_frag) {                        /* more to come, save */
  238                 ni->ni_rxfragstamp = ticks;
  239                 ni->ni_rxfrag[0] = mfrag;
  240                 mfrag = NULL;
  241         }
  242         return mfrag;
  243 }
  244 
  245 void
  246 ieee80211_deliver_data(struct ieee80211vap *vap,
  247         struct ieee80211_node *ni, struct mbuf *m)
  248 {
  249         struct ether_header *eh = mtod(m, struct ether_header *);
  250         struct ifnet *ifp = vap->iv_ifp;
  251 
  252         /* clear driver/net80211 flags before passing up */
  253         m->m_flags &= ~(M_80211_RX | M_MCAST | M_BCAST);
  254 
  255         /* NB: see hostap_deliver_data, this path doesn't handle hostap */
  256         KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
  257         /*
  258          * Do accounting.
  259          */
  260         ifp->if_ipackets++;
  261         IEEE80211_NODE_STAT(ni, rx_data);
  262         IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
  263         if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
  264                 m->m_flags |= M_MCAST;          /* XXX M_BCAST? */
  265                 IEEE80211_NODE_STAT(ni, rx_mcast);
  266         } else
  267                 IEEE80211_NODE_STAT(ni, rx_ucast);
  268         m->m_pkthdr.rcvif = ifp;
  269 
  270         if (ni->ni_vlan != 0) {
  271                 /* attach vlan tag */
  272                 m->m_pkthdr.ether_vtag = ni->ni_vlan;
  273                 m->m_flags |= M_VLANTAG;
  274         }
  275         ifp->if_input(ifp, m);
  276 }
  277 
  278 struct mbuf *
  279 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
  280 {
  281         struct ieee80211_qosframe_addr4 wh;
  282         struct ether_header *eh;
  283         struct llc *llc;
  284 
  285         KASSERT(hdrlen <= sizeof(wh),
  286             ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
  287 
  288         if (m->m_len < hdrlen + sizeof(*llc) &&
  289             (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
  290                 vap->iv_stats.is_rx_tooshort++;
  291                 /* XXX msg */
  292                 return NULL;
  293         }
  294         memcpy(&wh, mtod(m, caddr_t), hdrlen);
  295         llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
  296         if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
  297             llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
  298             llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
  299             /* NB: preserve AppleTalk frames that have a native SNAP hdr */
  300             !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
  301               llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
  302                 m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
  303                 llc = NULL;
  304         } else {
  305                 m_adj(m, hdrlen - sizeof(*eh));
  306         }
  307         eh = mtod(m, struct ether_header *);
  308         switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
  309         case IEEE80211_FC1_DIR_NODS:
  310                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
  311                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
  312                 break;
  313         case IEEE80211_FC1_DIR_TODS:
  314                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
  315                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
  316                 break;
  317         case IEEE80211_FC1_DIR_FROMDS:
  318                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
  319                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
  320                 break;
  321         case IEEE80211_FC1_DIR_DSTODS:
  322                 IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
  323                 IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
  324                 break;
  325         }
  326 #ifdef ALIGNED_POINTER
  327         if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
  328                 m = ieee80211_realign(vap, m, sizeof(*eh));
  329                 if (m == NULL)
  330                         return NULL;
  331         }
  332 #endif /* ALIGNED_POINTER */
  333         if (llc != NULL) {
  334                 eh = mtod(m, struct ether_header *);
  335                 eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
  336         }
  337         return m;
  338 }
  339 
  340 /*
  341  * Decap a frame encapsulated in a fast-frame/A-MSDU.
  342  */
  343 struct mbuf *
  344 ieee80211_decap1(struct mbuf *m, int *framelen)
  345 {
  346 #define FF_LLC_SIZE     (sizeof(struct ether_header) + sizeof(struct llc))
  347         struct ether_header *eh;
  348         struct llc *llc;
  349 
  350         /*
  351          * The frame has an 802.3 header followed by an 802.2
  352          * LLC header.  The encapsulated frame length is in the
  353          * first header type field; save that and overwrite it 
  354          * with the true type field found in the second.  Then
  355          * copy the 802.3 header up to where it belongs and
  356          * adjust the mbuf contents to remove the void.
  357          */
  358         if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
  359                 return NULL;
  360         eh = mtod(m, struct ether_header *);    /* 802.3 header is first */
  361         llc = (struct llc *)&eh[1];             /* 802.2 header follows */
  362         *framelen = ntohs(eh->ether_type)       /* encap'd frame size */
  363                   + sizeof(struct ether_header) - sizeof(struct llc);
  364         eh->ether_type = llc->llc_un.type_snap.ether_type;
  365         ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
  366                 sizeof(struct ether_header));
  367         m_adj(m, sizeof(struct llc));
  368         return m;
  369 #undef FF_LLC_SIZE
  370 }
  371 
  372 /*
  373  * Install received rate set information in the node's state block.
  374  */
  375 int
  376 ieee80211_setup_rates(struct ieee80211_node *ni,
  377         const uint8_t *rates, const uint8_t *xrates, int flags)
  378 {
  379         struct ieee80211vap *vap = ni->ni_vap;
  380         struct ieee80211_rateset *rs = &ni->ni_rates;
  381 
  382         memset(rs, 0, sizeof(*rs));
  383         rs->rs_nrates = rates[1];
  384         memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
  385         if (xrates != NULL) {
  386                 uint8_t nxrates;
  387                 /*
  388                  * Tack on 11g extended supported rate element.
  389                  */
  390                 nxrates = xrates[1];
  391                 if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
  392                         nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
  393                         IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
  394                             "extended rate set too large; only using "
  395                             "%u of %u rates", nxrates, xrates[1]);
  396                         vap->iv_stats.is_rx_rstoobig++;
  397                 }
  398                 memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
  399                 rs->rs_nrates += nxrates;
  400         }
  401         return ieee80211_fix_rate(ni, rs, flags);
  402 }
  403 
  404 /*
  405  * Send a management frame error response to the specified
  406  * station.  If ni is associated with the station then use
  407  * it; otherwise allocate a temporary node suitable for
  408  * transmitting the frame and then free the reference so
  409  * it will go away as soon as the frame has been transmitted.
  410  */
  411 void
  412 ieee80211_send_error(struct ieee80211_node *ni,
  413         const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
  414 {
  415         struct ieee80211vap *vap = ni->ni_vap;
  416         int istmp;
  417 
  418         if (ni == vap->iv_bss) {
  419                 if (vap->iv_state != IEEE80211_S_RUN) {
  420                         /*
  421                          * XXX hack until we get rid of this routine.
  422                          * We can be called prior to the vap reaching
  423                          * run state under certain conditions in which
  424                          * case iv_bss->ni_chan will not be setup.
  425                          * Check for this explicitly and and just ignore
  426                          * the request.
  427                          */
  428                         return;
  429                 }
  430                 ni = ieee80211_tmp_node(vap, mac);
  431                 if (ni == NULL) {
  432                         /* XXX msg */
  433                         return;
  434                 }
  435                 istmp = 1;
  436         } else
  437                 istmp = 0;
  438         IEEE80211_SEND_MGMT(ni, subtype, arg);
  439         if (istmp)
  440                 ieee80211_free_node(ni);
  441 }
  442 
  443 int
  444 ieee80211_alloc_challenge(struct ieee80211_node *ni)
  445 {
  446         if (ni->ni_challenge == NULL)
  447                 ni->ni_challenge = (uint32_t *) malloc(IEEE80211_CHALLENGE_LEN,
  448                     M_80211_NODE, M_NOWAIT);
  449         if (ni->ni_challenge == NULL) {
  450                 IEEE80211_NOTE(ni->ni_vap,
  451                     IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
  452                     "%s", "shared key challenge alloc failed");
  453                 /* XXX statistic */
  454         }
  455         return (ni->ni_challenge != NULL);
  456 }
  457 
  458 /*
  459  * Parse a Beacon or ProbeResponse frame and return the
  460  * useful information in an ieee80211_scanparams structure.
  461  * Status is set to 0 if no problems were found; otherwise
  462  * a bitmask of IEEE80211_BPARSE_* items is returned that
  463  * describes the problems detected.
  464  */
  465 int
  466 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
  467         struct ieee80211_scanparams *scan)
  468 {
  469         struct ieee80211vap *vap = ni->ni_vap;
  470         struct ieee80211com *ic = ni->ni_ic;
  471         struct ieee80211_frame *wh;
  472         uint8_t *frm, *efrm;
  473 
  474         wh = mtod(m, struct ieee80211_frame *);
  475         frm = (uint8_t *)&wh[1];
  476         efrm = mtod(m, uint8_t *) + m->m_len;
  477         scan->status = 0;
  478         /*
  479          * beacon/probe response frame format
  480          *      [8] time stamp
  481          *      [2] beacon interval
  482          *      [2] capability information
  483          *      [tlv] ssid
  484          *      [tlv] supported rates
  485          *      [tlv] country information
  486          *      [tlv] channel switch announcement (CSA)
  487          *      [tlv] parameter set (FH/DS)
  488          *      [tlv] erp information
  489          *      [tlv] extended supported rates
  490          *      [tlv] WME
  491          *      [tlv] WPA or RSN
  492          *      [tlv] HT capabilities
  493          *      [tlv] HT information
  494          *      [tlv] Atheros capabilities
  495          *      [tlv] Mesh ID
  496          *      [tlv] Mesh Configuration
  497          */
  498         IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
  499             return (scan->status = IEEE80211_BPARSE_BADIELEN));
  500         memset(scan, 0, sizeof(*scan));
  501         scan->tstamp  = frm;                            frm += 8;
  502         scan->bintval = le16toh(*(uint16_t *)frm);      frm += 2;
  503         scan->capinfo = le16toh(*(uint16_t *)frm);      frm += 2;
  504         scan->bchan = ieee80211_chan2ieee(ic, ic->ic_curchan);
  505         scan->chan = scan->bchan;
  506         scan->ies = frm;
  507         scan->ies_len = efrm - frm;
  508 
  509         while (efrm - frm > 1) {
  510                 IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
  511                     return (scan->status = IEEE80211_BPARSE_BADIELEN));
  512                 switch (*frm) {
  513                 case IEEE80211_ELEMID_SSID:
  514                         scan->ssid = frm;
  515                         break;
  516                 case IEEE80211_ELEMID_RATES:
  517                         scan->rates = frm;
  518                         break;
  519                 case IEEE80211_ELEMID_COUNTRY:
  520                         scan->country = frm;
  521                         break;
  522                 case IEEE80211_ELEMID_CSA:
  523                         scan->csa = frm;
  524                         break;
  525                 case IEEE80211_ELEMID_FHPARMS:
  526                         if (ic->ic_phytype == IEEE80211_T_FH) {
  527                                 scan->fhdwell = LE_READ_2(&frm[2]);
  528                                 scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
  529                                 scan->fhindex = frm[6];
  530                         }
  531                         break;
  532                 case IEEE80211_ELEMID_DSPARMS:
  533                         /*
  534                          * XXX hack this since depending on phytype
  535                          * is problematic for multi-mode devices.
  536                          */
  537                         if (ic->ic_phytype != IEEE80211_T_FH)
  538                                 scan->chan = frm[2];
  539                         break;
  540                 case IEEE80211_ELEMID_TIM:
  541                         /* XXX ATIM? */
  542                         scan->tim = frm;
  543                         scan->timoff = frm - mtod(m, uint8_t *);
  544                         break;
  545                 case IEEE80211_ELEMID_IBSSPARMS:
  546                 case IEEE80211_ELEMID_CFPARMS:
  547                 case IEEE80211_ELEMID_PWRCNSTR:
  548                         /* NB: avoid debugging complaints */
  549                         break;
  550                 case IEEE80211_ELEMID_XRATES:
  551                         scan->xrates = frm;
  552                         break;
  553                 case IEEE80211_ELEMID_ERP:
  554                         if (frm[1] != 1) {
  555                                 IEEE80211_DISCARD_IE(vap,
  556                                     IEEE80211_MSG_ELEMID, wh, "ERP",
  557                                     "bad len %u", frm[1]);
  558                                 vap->iv_stats.is_rx_elem_toobig++;
  559                                 break;
  560                         }
  561                         scan->erp = frm[2] | 0x100;
  562                         break;
  563                 case IEEE80211_ELEMID_HTCAP:
  564                         scan->htcap = frm;
  565                         break;
  566                 case IEEE80211_ELEMID_RSN:
  567                         scan->rsn = frm;
  568                         break;
  569                 case IEEE80211_ELEMID_HTINFO:
  570                         scan->htinfo = frm;
  571                         break;
  572 #ifdef IEEE80211_SUPPORT_MESH
  573                 case IEEE80211_ELEMID_MESHID:
  574                         scan->meshid = frm;
  575                         break;
  576                 case IEEE80211_ELEMID_MESHCONF:
  577                         scan->meshconf = frm;
  578                         break;
  579 #endif
  580                 case IEEE80211_ELEMID_VENDOR:
  581                         if (iswpaoui(frm))
  582                                 scan->wpa = frm;
  583                         else if (iswmeparam(frm) || iswmeinfo(frm))
  584                                 scan->wme = frm;
  585 #ifdef IEEE80211_SUPPORT_SUPERG
  586                         else if (isatherosoui(frm))
  587                                 scan->ath = frm;
  588 #endif
  589 #ifdef IEEE80211_SUPPORT_TDMA
  590                         else if (istdmaoui(frm))
  591                                 scan->tdma = frm;
  592 #endif
  593                         else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
  594                                 /*
  595                                  * Accept pre-draft HT ie's if the
  596                                  * standard ones have not been seen.
  597                                  */
  598                                 if (ishtcapoui(frm)) {
  599                                         if (scan->htcap == NULL)
  600                                                 scan->htcap = frm;
  601                                 } else if (ishtinfooui(frm)) {
  602                                         if (scan->htinfo == NULL)
  603                                                 scan->htcap = frm;
  604                                 }
  605                         }
  606                         break;
  607                 default:
  608                         IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
  609                             wh, "unhandled",
  610                             "id %u, len %u", *frm, frm[1]);
  611                         vap->iv_stats.is_rx_elem_unknown++;
  612                         break;
  613                 }
  614                 frm += frm[1] + 2;
  615         }
  616         IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
  617             scan->status |= IEEE80211_BPARSE_RATES_INVALID);
  618         if (scan->rates != NULL && scan->xrates != NULL) {
  619                 /*
  620                  * NB: don't process XRATES if RATES is missing.  This
  621                  * avoids a potential null ptr deref and should be ok
  622                  * as the return code will already note RATES is missing
  623                  * (so callers shouldn't otherwise process the frame).
  624                  */
  625                 IEEE80211_VERIFY_ELEMENT(scan->xrates,
  626                     IEEE80211_RATE_MAXSIZE - scan->rates[1],
  627                     scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
  628         }
  629         IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
  630             scan->status |= IEEE80211_BPARSE_SSID_INVALID);
  631         if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
  632                 /*
  633                  * Frame was received on a channel different from the
  634                  * one indicated in the DS params element id;
  635                  * silently discard it.
  636                  *
  637                  * NB: this can happen due to signal leakage.
  638                  *     But we should take it for FH phy because
  639                  *     the rssi value should be correct even for
  640                  *     different hop pattern in FH.
  641                  */
  642                 IEEE80211_DISCARD(vap,
  643                     IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
  644                     wh, NULL, "for off-channel %u", scan->chan);
  645                 vap->iv_stats.is_rx_chanmismatch++;
  646                 scan->status |= IEEE80211_BPARSE_OFFCHAN;
  647         }
  648         if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
  649               scan->bintval <= IEEE80211_BINTVAL_MAX)) {
  650                 IEEE80211_DISCARD(vap,
  651                     IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
  652                     wh, NULL, "bogus beacon interval", scan->bintval);
  653                 vap->iv_stats.is_rx_badbintval++;
  654                 scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
  655         }
  656         if (scan->country != NULL) {
  657                 /*
  658                  * Validate we have at least enough data to extract
  659                  * the country code.  Not sure if we should return an
  660                  * error instead of discarding the IE; consider this
  661                  * being lenient as we don't depend on the data for
  662                  * correct operation.
  663                  */
  664                 IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
  665                     scan->country = NULL);
  666         }
  667         if (scan->csa != NULL) {
  668                 /*
  669                  * Validate Channel Switch Announcement; this must
  670                  * be the correct length or we toss the frame.
  671                  */
  672                 IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
  673                     scan->status |= IEEE80211_BPARSE_CSA_INVALID);
  674         }
  675         /*
  676          * Process HT ie's.  This is complicated by our
  677          * accepting both the standard ie's and the pre-draft
  678          * vendor OUI ie's that some vendors still use/require.
  679          */
  680         if (scan->htcap != NULL) {
  681                 IEEE80211_VERIFY_LENGTH(scan->htcap[1],
  682                      scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
  683                          4 + sizeof(struct ieee80211_ie_htcap)-2 :
  684                          sizeof(struct ieee80211_ie_htcap)-2,
  685                      scan->htcap = NULL);
  686         }
  687         if (scan->htinfo != NULL) {
  688                 IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
  689                      scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
  690                          4 + sizeof(struct ieee80211_ie_htinfo)-2 :
  691                          sizeof(struct ieee80211_ie_htinfo)-2,
  692                      scan->htinfo = NULL);
  693         }
  694         return scan->status;
  695 }
  696 
  697 /*
  698  * Parse an Action frame.  Return 0 on success, non-zero on failure.
  699  */
  700 int
  701 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
  702 {
  703         struct ieee80211vap *vap = ni->ni_vap;
  704         const struct ieee80211_action *ia;
  705         struct ieee80211_frame *wh;
  706         uint8_t *frm, *efrm;
  707 
  708         /*
  709          * action frame format:
  710          *      [1] category
  711          *      [1] action
  712          *      [tlv] parameters
  713          */
  714         wh = mtod(m, struct ieee80211_frame *);
  715         frm = (u_int8_t *)&wh[1];
  716         efrm = mtod(m, u_int8_t *) + m->m_len;
  717         IEEE80211_VERIFY_LENGTH(efrm - frm,
  718                 sizeof(struct ieee80211_action), return EINVAL);
  719         ia = (const struct ieee80211_action *) frm;
  720 
  721         vap->iv_stats.is_rx_action++;
  722         IEEE80211_NODE_STAT(ni, rx_action);
  723 
  724         /* verify frame payloads but defer processing */
  725         switch (ia->ia_category) {
  726         case IEEE80211_ACTION_CAT_BA:
  727                 switch (ia->ia_action) {
  728                 case IEEE80211_ACTION_BA_ADDBA_REQUEST:
  729                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  730                             sizeof(struct ieee80211_action_ba_addbarequest),
  731                             return EINVAL);
  732                         break;
  733                 case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
  734                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  735                             sizeof(struct ieee80211_action_ba_addbaresponse),
  736                             return EINVAL);
  737                         break;
  738                 case IEEE80211_ACTION_BA_DELBA:
  739                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  740                             sizeof(struct ieee80211_action_ba_delba),
  741                             return EINVAL);
  742                         break;
  743                 }
  744                 break;
  745         case IEEE80211_ACTION_CAT_HT:
  746                 switch (ia->ia_action) {
  747                 case IEEE80211_ACTION_HT_TXCHWIDTH:
  748                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  749                             sizeof(struct ieee80211_action_ht_txchwidth),
  750                             return EINVAL);
  751                         break;
  752                 case IEEE80211_ACTION_HT_MIMOPWRSAVE:
  753                         IEEE80211_VERIFY_LENGTH(efrm - frm,
  754                             sizeof(struct ieee80211_action_ht_mimopowersave),
  755                             return EINVAL);
  756                         break;
  757                 }
  758                 break;
  759         }
  760         return 0;
  761 }
  762 
  763 #ifdef IEEE80211_DEBUG
  764 /*
  765  * Debugging support.
  766  */
  767 void
  768 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
  769         uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
  770 {
  771         printf("[%s] discard %s frame, ssid mismatch: ",
  772                 ether_sprintf(mac), tag);
  773         ieee80211_print_essid(ssid + 2, ssid[1]);
  774         printf("\n");
  775 }
  776 
  777 /*
  778  * Return the bssid of a frame.
  779  */
  780 static const uint8_t *
  781 ieee80211_getbssid(const struct ieee80211vap *vap,
  782         const struct ieee80211_frame *wh)
  783 {
  784         if (vap->iv_opmode == IEEE80211_M_STA)
  785                 return wh->i_addr2;
  786         if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
  787                 return wh->i_addr1;
  788         if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
  789                 return wh->i_addr1;
  790         return wh->i_addr3;
  791 }
  792 
  793 #include <machine/stdarg.h>
  794 
  795 void
  796 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
  797 {
  798         char buf[128];          /* XXX */
  799         va_list ap;
  800 
  801         va_start(ap, fmt);
  802         vsnprintf(buf, sizeof(buf), fmt, ap);
  803         va_end(ap);
  804 
  805         if_printf(vap->iv_ifp, "%s", buf);      /* NB: no \n */
  806 }
  807 
  808 void
  809 ieee80211_note_frame(const struct ieee80211vap *vap,
  810         const struct ieee80211_frame *wh,
  811         const char *fmt, ...)
  812 {
  813         char buf[128];          /* XXX */
  814         va_list ap;
  815 
  816         va_start(ap, fmt);
  817         vsnprintf(buf, sizeof(buf), fmt, ap);
  818         va_end(ap);
  819         if_printf(vap->iv_ifp, "[%s] %s\n",
  820                 ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
  821 }
  822 
  823 void
  824 ieee80211_note_mac(const struct ieee80211vap *vap,
  825         const uint8_t mac[IEEE80211_ADDR_LEN],
  826         const char *fmt, ...)
  827 {
  828         char buf[128];          /* XXX */
  829         va_list ap;
  830 
  831         va_start(ap, fmt);
  832         vsnprintf(buf, sizeof(buf), fmt, ap);
  833         va_end(ap);
  834         if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
  835 }
  836 
  837 void
  838 ieee80211_discard_frame(const struct ieee80211vap *vap,
  839         const struct ieee80211_frame *wh,
  840         const char *type, const char *fmt, ...)
  841 {
  842         va_list ap;
  843 
  844         if_printf(vap->iv_ifp, "[%s] discard ",
  845                 ether_sprintf(ieee80211_getbssid(vap, wh)));
  846         if (type == NULL) {
  847                 printf("%s frame, ", ieee80211_mgt_subtype_name[
  848                         (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) >>
  849                         IEEE80211_FC0_SUBTYPE_SHIFT]);
  850         } else
  851                 printf("%s frame, ", type);
  852         va_start(ap, fmt);
  853         vprintf(fmt, ap);
  854         va_end(ap);
  855         printf("\n");
  856 }
  857 
  858 void
  859 ieee80211_discard_ie(const struct ieee80211vap *vap,
  860         const struct ieee80211_frame *wh,
  861         const char *type, const char *fmt, ...)
  862 {
  863         va_list ap;
  864 
  865         if_printf(vap->iv_ifp, "[%s] discard ",
  866                 ether_sprintf(ieee80211_getbssid(vap, wh)));
  867         if (type != NULL)
  868                 printf("%s information element, ", type);
  869         else
  870                 printf("information element, ");
  871         va_start(ap, fmt);
  872         vprintf(fmt, ap);
  873         va_end(ap);
  874         printf("\n");
  875 }
  876 
  877 void
  878 ieee80211_discard_mac(const struct ieee80211vap *vap,
  879         const uint8_t mac[IEEE80211_ADDR_LEN],
  880         const char *type, const char *fmt, ...)
  881 {
  882         va_list ap;
  883 
  884         if_printf(vap->iv_ifp, "[%s] discard ", ether_sprintf(mac));
  885         if (type != NULL)
  886                 printf("%s frame, ", type);
  887         else
  888                 printf("frame, ");
  889         va_start(ap, fmt);
  890         vprintf(fmt, ap);
  891         va_end(ap);
  892         printf("\n");
  893 }
  894 #endif /* IEEE80211_DEBUG */

Cache object: 2b75133138f731b8ead4cc0c3769be87


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.