FreeBSD/Linux Kernel Cross Reference
sys/net80211/ieee80211_node.c

     /*      $NetBSD: ieee80211_node.c,v 1.61 2008/06/24 10:33:08 gmcgarry Exp $     */
     /*-
      * Copyright (c) 2001 Atsushi Onoe
      * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions
      * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. The name of the author may not be used to endorse or promote products
     *    derived from this software without specific prior written permission.
     *
     * Alternatively, this software may be distributed under the terms of the
     * GNU General Public License ("GPL") version 2 as published by the Free
     * Software Foundation.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     */
    
    #include <sys/cdefs.h>
    #ifdef __FreeBSD__
    __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_node.c,v 1.65 2005/08/13 17:50:21 sam Exp $");
    #endif
    #ifdef __NetBSD__
    __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.61 2008/06/24 10:33:08 gmcgarry Exp $");
    #endif
    
    #include "opt_inet.h"
    
    #include <sys/param.h>
    #include <sys/systm.h> 
    #include <sys/mbuf.h>   
    #include <sys/malloc.h>
    #include <sys/kernel.h>
    
    #include <sys/socket.h>
    #include <sys/sockio.h>
    #include <sys/endian.h>
    #include <sys/errno.h>
    #include <sys/proc.h>
    #include <sys/sysctl.h>
    
    #include <net/if.h>
    #include <net/if_media.h>
    #include <net/if_arp.h>
    #include <net/if_ether.h>
    #include <net/if_llc.h>
    
    #include <net80211/ieee80211_netbsd.h>
    #include <net80211/ieee80211_var.h>
    
    #include <net/bpf.h>
    
    #ifdef INET
    #include <netinet/in.h> 
    #include <net/if_ether.h>
    #endif
    
    /*
     * Association id's are managed with a bit vector.
     */
    #define IEEE80211_AID_SET(b, w) \
            ((w)[IEEE80211_AID(b) / 32] |= (1 << (IEEE80211_AID(b) % 32)))
    #define IEEE80211_AID_CLR(b, w) \
            ((w)[IEEE80211_AID(b) / 32] &= ~(1 << (IEEE80211_AID(b) % 32)))
    #define IEEE80211_AID_ISSET(b, w) \
            ((w)[IEEE80211_AID(b) / 32] & (1 << (IEEE80211_AID(b) % 32)))
    
    static struct ieee80211_node *node_alloc(struct ieee80211_node_table *);
    static void node_cleanup(struct ieee80211_node *);
    static void node_free(struct ieee80211_node *);
    static u_int8_t node_getrssi(const struct ieee80211_node *);
    
    static void ieee80211_setup_node(struct ieee80211_node_table *,
                    struct ieee80211_node *, const u_int8_t *);
    static void _ieee80211_free_node(struct ieee80211_node *);
    static void ieee80211_free_allnodes(struct ieee80211_node_table *);
    
    static void ieee80211_timeout_scan_candidates(struct ieee80211_node_table *);
    static void ieee80211_timeout_stations(struct ieee80211_node_table *);
    
    static void ieee80211_set_tim(struct ieee80211_node *, int set);
    
    static void ieee80211_node_table_init(struct ieee80211com *ic,
            struct ieee80211_node_table *nt, const char *name,
           int inact, int keyixmax,
           void (*timeout)(struct ieee80211_node_table *));
   static void ieee80211_node_table_cleanup(struct ieee80211_node_table *nt);
   
   MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state");
   
   void
   ieee80211_node_attach(struct ieee80211com *ic)
   {
   
           ic->ic_node_alloc = node_alloc;
           ic->ic_node_free = node_free;
           ic->ic_node_cleanup = node_cleanup;
           ic->ic_node_getrssi = node_getrssi;
   
           /* default station inactivity timer setings */
           ic->ic_inact_init = IEEE80211_INACT_INIT;
           ic->ic_inact_auth = IEEE80211_INACT_AUTH;
           ic->ic_inact_run = IEEE80211_INACT_RUN;
           ic->ic_inact_probe = IEEE80211_INACT_PROBE;
   
           /* NB: driver should override */
           ic->ic_max_aid = IEEE80211_AID_DEF;
           ic->ic_set_tim = ieee80211_set_tim;
   }
   
   void
   ieee80211_node_lateattach(struct ieee80211com *ic)
   {
           struct ieee80211_rsnparms *rsn;
   
           if (ic->ic_max_aid > IEEE80211_AID_MAX)
                   ic->ic_max_aid = IEEE80211_AID_MAX;
           ic->ic_aid_bitmap = malloc(howmany(ic->ic_max_aid, 32) *
               sizeof(u_int32_t), M_DEVBUF, M_NOWAIT | M_ZERO);
           if (ic->ic_aid_bitmap == NULL) {
                   /* XXX no way to recover */
                   printf("%s: no memory for AID bitmap!\n", __func__);
                   ic->ic_max_aid = 0;
           }
   
           /* XXX defer until using hostap/ibss mode */
           ic->ic_tim_len = howmany(ic->ic_max_aid, 8) * sizeof(u_int8_t);
           ic->ic_tim_bitmap = malloc(ic->ic_tim_len, M_DEVBUF, M_NOWAIT | M_ZERO);
           if (ic->ic_tim_bitmap == NULL) {
                   /* XXX no way to recover */
                   printf("%s: no memory for TIM bitmap!\n", __func__);
           }
   
           ieee80211_node_table_init(ic, &ic->ic_sta, "station",
                   IEEE80211_INACT_INIT, ic->ic_crypto.cs_max_keyix,
                   ieee80211_timeout_stations);
           ieee80211_node_table_init(ic, &ic->ic_scan, "scan",
                   IEEE80211_INACT_SCAN, 0,
                   ieee80211_timeout_scan_candidates);
   
           ieee80211_reset_bss(ic);
           /*
            * Setup "global settings" in the bss node so that
            * each new station automatically inherits them.
            */
           rsn = &ic->ic_bss->ni_rsn;
           /* WEP, TKIP, and AES-CCM are always supported */
           rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_WEP;
           rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_TKIP;
           rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_CCM;
           if (ic->ic_caps & IEEE80211_C_AES)
                   rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_AES_OCB;
           if (ic->ic_caps & IEEE80211_C_CKIP)
                   rsn->rsn_ucastcipherset |= 1<<IEEE80211_CIPHER_CKIP;
           /*
            * Default unicast cipher to WEP for 802.1x use.  If
            * WPA is enabled the management code will set these
            * values to reflect.
            */
           rsn->rsn_ucastcipher = IEEE80211_CIPHER_WEP;
           rsn->rsn_ucastkeylen = 104 / NBBY;
           /*
            * WPA says the multicast cipher is the lowest unicast
            * cipher supported.  But we skip WEP which would
            * otherwise be used based on this criteria.
            */
           rsn->rsn_mcastcipher = IEEE80211_CIPHER_TKIP;
           rsn->rsn_mcastkeylen = 128 / NBBY;
   
           /*
            * We support both WPA-PSK and 802.1x; the one used
            * is determined by the authentication mode and the
            * setting of the PSK state.
            */
           rsn->rsn_keymgmtset = WPA_ASE_8021X_UNSPEC | WPA_ASE_8021X_PSK;
           rsn->rsn_keymgmt = WPA_ASE_8021X_PSK;
   
           ic->ic_auth = ieee80211_authenticator_get(ic->ic_bss->ni_authmode);
   }
   
   void
   ieee80211_node_detach(struct ieee80211com *ic)
   {
   
           if (ic->ic_bss != NULL) {
                   ieee80211_free_node(ic->ic_bss);
                   ic->ic_bss = NULL;
           }
           ieee80211_node_table_cleanup(&ic->ic_scan);
           ieee80211_node_table_cleanup(&ic->ic_sta);
           if (ic->ic_aid_bitmap != NULL) {
                   FREE(ic->ic_aid_bitmap, M_DEVBUF);
                   ic->ic_aid_bitmap = NULL;
           }
           if (ic->ic_tim_bitmap != NULL) {
                   FREE(ic->ic_tim_bitmap, M_DEVBUF);
                   ic->ic_tim_bitmap = NULL;
           }
   }
   
   /* 
    * Port authorize/unauthorize interfaces for use by an authenticator.
    */
   
   void
   ieee80211_node_authorize(struct ieee80211_node *ni)
   {
           struct ieee80211com *ic = ni->ni_ic;
   
           ni->ni_flags |= IEEE80211_NODE_AUTH;
           ni->ni_inact_reload = ic->ic_inact_run;
   }
   
   void
   ieee80211_node_unauthorize(struct ieee80211_node *ni)
   {
           ni->ni_flags &= ~IEEE80211_NODE_AUTH;
   }
   
   /*
    * Set/change the channel.  The rate set is also updated as
    * to insure a consistent view by drivers.
    */
   static void
   ieee80211_set_chan(struct ieee80211com *ic,
           struct ieee80211_node *ni, struct ieee80211_channel *chan)
   {
           if (chan == IEEE80211_CHAN_ANYC)        /* XXX while scanning */
                   chan = ic->ic_curchan;
           ni->ni_chan = chan;
           ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
   }
   
   /*
    * AP scanning support.
    */
   
   #ifdef IEEE80211_DEBUG
   static void
   dump_chanlist(const u_char chans[])
   {
           const char *sep;
           int i;
   
           sep = " ";
           for (i = 0; i < IEEE80211_CHAN_MAX; i++)
                   if (isset(chans, i)) {
                           printf("%s%u", sep, i);
                           sep = ", ";
                   }
   }
   #endif /* IEEE80211_DEBUG */
   
   /*
    * Initialize the channel set to scan based on the
    * of available channels and the current PHY mode.
    */
   static void
   ieee80211_reset_scan(struct ieee80211com *ic)
   {
   
           /* XXX ic_des_chan should be handled with ic_chan_active */
           if (ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
                   memset(ic->ic_chan_scan, 0, sizeof(ic->ic_chan_scan));
                   setbit(ic->ic_chan_scan,
                           ieee80211_chan2ieee(ic, ic->ic_des_chan));
           } else
                   memcpy(ic->ic_chan_scan, ic->ic_chan_active,
                           sizeof(ic->ic_chan_active));
   #ifdef IEEE80211_DEBUG
           if (ieee80211_msg_scan(ic)) {
                   printf("%s: scan set:", __func__);
                   dump_chanlist(ic->ic_chan_scan);
                   printf(" start chan %u\n",
                           ieee80211_chan2ieee(ic, ic->ic_curchan));
           }
   #endif /* IEEE80211_DEBUG */
   }
   
   /*
    * Begin an active scan.
    */
   void
   ieee80211_begin_scan(struct ieee80211com *ic, int reset)
   {
   
           ic->ic_scan.nt_scangen++;
           /*
            * In all but hostap mode scanning starts off in
            * an active mode before switching to passive.
            */
           if (ic->ic_opmode != IEEE80211_M_HOSTAP) {
                   ic->ic_flags |= IEEE80211_F_ASCAN;
                   ic->ic_stats.is_scan_active++;
           } else
                   ic->ic_stats.is_scan_passive++;
           IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
                   "begin %s scan in %s mode, scangen %u\n",
                   (ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive",
                   ieee80211_phymode_name[ic->ic_curmode], ic->ic_scan.nt_scangen);
           /*
            * Clear scan state and flush any previously seen AP's.
            */
           ieee80211_reset_scan(ic);
           if (reset)
                   ieee80211_free_allnodes(&ic->ic_scan);
   
           ic->ic_flags |= IEEE80211_F_SCAN;
   
           /* Scan the next channel. */
           ieee80211_next_scan(ic);
   }
   
   /*
    * Switch to the next channel marked for scanning.
    */
   int
   ieee80211_next_scan(struct ieee80211com *ic)
   {
           struct ieee80211_channel *chan;
   
           /*
            * Insure any previous mgt frame timeouts don't fire.
            * This assumes the driver does the right thing in
            * flushing anything queued in the driver and below.
            */
           ic->ic_mgt_timer = 0;
           ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
   
           chan = ic->ic_curchan;
           do {
                   if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX])
                           chan = &ic->ic_channels[0];
                   if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) {
                           clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan));
                           IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
                               "%s: chan %d->%d\n", __func__,
                               ieee80211_chan2ieee(ic, ic->ic_curchan),
                               ieee80211_chan2ieee(ic, chan));
                           ic->ic_curchan = chan;
                           /*
                            * XXX drivers should do this as needed,
                            * XXX for now maintain compatibility
                            */
                           ic->ic_bss->ni_rates =
                                   ic->ic_sup_rates[ieee80211_chan2mode(ic, chan)];
                           ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
                           return 1;
                   }
           } while (chan != ic->ic_curchan);
           ieee80211_end_scan(ic);
           return 0;
   }
   
   /*
    * Probe the curent channel, if allowed, while scanning.
    * If the channel is not marked passive-only then send
    * a probe request immediately.  Otherwise mark state and
    * listen for beacons on the channel; if we receive something
    * then we'll transmit a probe request.
    */
   void
   ieee80211_probe_curchan(struct ieee80211com *ic, int force)
   {
           struct ifnet *ifp = ic->ic_ifp;
   
           if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 || force) {
                   /*
                    * XXX send both broadcast+directed probe request
                    */
                   ieee80211_send_probereq(ic->ic_bss,
                           ic->ic_myaddr, ifp->if_broadcastaddr,
                           ifp->if_broadcastaddr,
                           ic->ic_des_essid, ic->ic_des_esslen,
                           ic->ic_opt_ie, ic->ic_opt_ie_len);
           } else
                   ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
   }
   
   static __inline void
   copy_bss(struct ieee80211_node *nbss, const struct ieee80211_node *obss)
   {
           /* propagate useful state */
           nbss->ni_authmode = obss->ni_authmode;
           nbss->ni_txpower = obss->ni_txpower;
           nbss->ni_vlan = obss->ni_vlan;
           nbss->ni_rsn = obss->ni_rsn;
           /* XXX statistics? */
   }
   
   void
   ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan)
   {
           struct ieee80211_node_table *nt;
           struct ieee80211_node *ni;
   
           IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
                   "%s: creating ibss\n", __func__);
   
           /*
            * Create the station/neighbor table.  Note that for adhoc
            * mode we make the initial inactivity timer longer since
            * we create nodes only through discovery and they typically
            * are long-lived associations.
            */
           nt = &ic->ic_sta;
           IEEE80211_NODE_LOCK(nt);
           if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
                   nt->nt_name = "station";
                   nt->nt_inact_init = ic->ic_inact_init;
           } else {
                   nt->nt_name = "neighbor";
                   nt->nt_inact_init = ic->ic_inact_run;
           }
           IEEE80211_NODE_UNLOCK(nt);
   
           ni = ieee80211_alloc_node(&ic->ic_sta, ic->ic_myaddr);
           if (ni == NULL) {
                   /* XXX recovery? */
                   return;
           }
           IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr);
           ni->ni_esslen = ic->ic_des_esslen;
           memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen);
           copy_bss(ni, ic->ic_bss);
           ni->ni_intval = ic->ic_bintval;
           if (ic->ic_flags & IEEE80211_F_PRIVACY)
                   ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY;
           if (ic->ic_phytype == IEEE80211_T_FH) {
                   ni->ni_fhdwell = 200;   /* XXX */
                   ni->ni_fhindex = 1;
           }
           if (ic->ic_opmode == IEEE80211_M_IBSS) {
                   ic->ic_flags |= IEEE80211_F_SIBSS;
                   ni->ni_capinfo |= IEEE80211_CAPINFO_IBSS;       /* XXX */
                   if (ic->ic_flags & IEEE80211_F_DESBSSID)
                           IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid);
                   else
                           ni->ni_bssid[0] |= 0x02;        /* local bit for IBSS */
           }
           /* 
            * Fix the channel and related attributes.
            */
           ieee80211_set_chan(ic, ni, chan);
           ic->ic_curchan = chan;
           ic->ic_curmode = ieee80211_chan2mode(ic, chan);
           /*
            * Do mode-specific rate setup.
            */
           if (ic->ic_curmode == IEEE80211_MODE_11G) {
                   /*
                    * Use a mixed 11b/11g rate set.
                    */
                   ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11G);
           } else if (ic->ic_curmode == IEEE80211_MODE_11B) {
                   /*
                    * Force pure 11b rate set.
                    */
                   ieee80211_set11gbasicrates(&ni->ni_rates, IEEE80211_MODE_11B);
           }
   
           (void) ieee80211_sta_join(ic, ieee80211_ref_node(ni));
   }
   
   void
   ieee80211_reset_bss(struct ieee80211com *ic)
   {
           struct ieee80211_node *ni, *obss;
   
           ieee80211_node_table_reset(&ic->ic_scan);
           ieee80211_node_table_reset(&ic->ic_sta);
   
           ni = ieee80211_alloc_node(&ic->ic_scan, ic->ic_myaddr);
           IASSERT(ni != NULL, ("unable to setup inital BSS node"));
           obss = ic->ic_bss;
           ic->ic_bss = ieee80211_ref_node(ni);
           if (obss != NULL) {
                   copy_bss(ni, obss);
                   ni->ni_intval = ic->ic_bintval;
                   ieee80211_free_node(obss);
           }
   }
   
   /* XXX tunable */
   #define STA_FAILS_MAX   2               /* assoc failures before ignored */
   
   static int
   ieee80211_match_bss(struct ieee80211com *ic, struct ieee80211_node *ni)
   {
           u_int8_t rate;
           int fail;
   
           fail = 0;
           if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ni->ni_chan)))
                   fail |= 0x01;
           if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
               ni->ni_chan != ic->ic_des_chan)
                   fail |= 0x01;
           if (ic->ic_opmode == IEEE80211_M_IBSS) {
                   if ((ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
                           fail |= 0x02;
           } else {
                   if ((ni->ni_capinfo & IEEE80211_CAPINFO_ESS) == 0)
                           fail |= 0x02;
           }
           if (ic->ic_flags & IEEE80211_F_PRIVACY) {
                   if ((ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
                           fail |= 0x04;
           } else {
                   /* XXX does this mean privacy is supported or required? */
                   if (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY)
                           fail |= 0x04;
           }
           rate = ieee80211_fix_rate(ni, IEEE80211_F_DONEGO | IEEE80211_F_DOFRATE);
           if (rate & IEEE80211_RATE_BASIC)
                   fail |= 0x08;
           if (ic->ic_des_esslen != 0 &&
               (ni->ni_esslen != ic->ic_des_esslen ||
                memcmp(ni->ni_essid, ic->ic_des_essid, ic->ic_des_esslen) != 0))
                   fail |= 0x10;
           if ((ic->ic_flags & IEEE80211_F_DESBSSID) &&
               !IEEE80211_ADDR_EQ(ic->ic_des_bssid, ni->ni_bssid))
                   fail |= 0x20;
           if (ni->ni_fails >= STA_FAILS_MAX)
                   fail |= 0x40;
   #ifdef IEEE80211_DEBUG
           if (ieee80211_msg_scan(ic)) {
                   printf(" %c %s",
                       fail & 0x40 ? '=' : fail & 0x80 ? '^' : fail ? '-' : '+',
                       ether_sprintf(ni->ni_macaddr));
                   printf(" %s%c", ether_sprintf(ni->ni_bssid),
                       fail & 0x20 ? '!' : ' ');
                   printf(" %3d%c", ieee80211_chan2ieee(ic, ni->ni_chan),
                           fail & 0x01 ? '!' : ' ');
                   printf(" %+4d", ni->ni_rssi);
                   printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
                       fail & 0x08 ? '!' : ' ');
                   printf(" %4s%c",
                       (ni->ni_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
                       (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
                       "????",
                       fail & 0x02 ? '!' : ' ');
                   printf(" %3s%c ",
                       (ni->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
                       "wep" : "no",
                       fail & 0x04 ? '!' : ' ');
                   ieee80211_print_essid(ni->ni_essid, ni->ni_esslen);
                   printf("%s\n", fail & 0x10 ? "!" : "");
           }
   #endif
           return fail;
   }
   
   static __inline u_int8_t
   maxrate(const struct ieee80211_node *ni)
   {
           const struct ieee80211_rateset *rs = &ni->ni_rates;
           /* NB: assumes rate set is sorted (happens on frame receive) */
           return rs->rs_rates[rs->rs_nrates-1] & IEEE80211_RATE_VAL;
   }
   
   /*
    * Compare the capabilities of two nodes and decide which is
    * more desirable (return >0 if a is considered better).  Note
    * that we assume compatibility/usability has already been checked
    * so we don't need to (e.g. validate whether privacy is supported).
    * Used to select the best scan candidate for association in a BSS.
    */
   static int
   ieee80211_node_compare(struct ieee80211com *ic,
                          const struct ieee80211_node *a,
                          const struct ieee80211_node *b)
   {
           u_int8_t maxa, maxb;
           u_int8_t rssia, rssib;
           int weight;
   
           /* privacy support preferred */
           if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) &&
               (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
                   return 1;
           if ((a->ni_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0 &&
               (b->ni_capinfo & IEEE80211_CAPINFO_PRIVACY))
                   return -1;
   
           /* compare count of previous failures */
           weight = b->ni_fails - a->ni_fails;
           if (abs(weight) > 1)
                   return weight;
   
           rssia = ic->ic_node_getrssi(a);
           rssib = ic->ic_node_getrssi(b);
           if (abs(rssib - rssia) < 5) {
                   /* best/max rate preferred if signal level close enough XXX */
                   maxa = maxrate(a);
                   maxb = maxrate(b);
                   if (maxa != maxb)
                           return maxa - maxb;
                   /* XXX use freq for channel preference */
                   /* for now just prefer 5 GHz band to all other bands */
                   if (IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
                      !IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
                           return 1;
                   if (!IEEE80211_IS_CHAN_5GHZ(a->ni_chan) &&
                        IEEE80211_IS_CHAN_5GHZ(b->ni_chan))
                           return -1;
           }
           /* all things being equal, use signal level */
           return rssia - rssib;
   }
   
   /*
    * Mark an ongoing scan stopped.
    */
   void
   ieee80211_cancel_scan(struct ieee80211com *ic)
   {
   
           IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "%s: end %s scan\n",
                   __func__,
                   (ic->ic_flags & IEEE80211_F_ASCAN) ?  "active" : "passive");
   
           ic->ic_flags &= ~(IEEE80211_F_SCAN | IEEE80211_F_ASCAN);
           ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
   }
   
   /*
    * Complete a scan of potential channels.
    */
   void
   ieee80211_end_scan(struct ieee80211com *ic)
   {
           struct ieee80211_node_table *nt = &ic->ic_scan;
           struct ieee80211_node *ni, *selbs;
   
           ieee80211_cancel_scan(ic);
           ieee80211_notify_scan_done(ic);
   
   #ifndef IEEE80211_NO_HOSTAP
           if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
                   u_int8_t maxrssi[IEEE80211_CHAN_MAX];   /* XXX off stack? */
                   int i, bestchan;
                   u_int8_t rssi;
   
                   /*
                    * The passive scan to look for existing AP's completed,
                    * select a channel to camp on.  Identify the channels
                    * that already have one or more AP's and try to locate
                    * an unoccupied one.  If that fails, pick a channel that
                    * looks to be quietest.
                    */
                   memset(maxrssi, 0, sizeof(maxrssi));
                   IEEE80211_NODE_LOCK(nt);
                   TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                           rssi = ic->ic_node_getrssi(ni);
                           i = ieee80211_chan2ieee(ic, ni->ni_chan);
                           if (rssi > maxrssi[i])
                                   maxrssi[i] = rssi;
                   }
                   IEEE80211_NODE_UNLOCK(nt);
                   /* XXX select channel more intelligently */
                   bestchan = -1;
                   for (i = 0; i < IEEE80211_CHAN_MAX; i++)
                           if (isset(ic->ic_chan_active, i)) {
                                   /*
                                    * If the channel is unoccupied the max rssi
                                    * should be zero; just take it.  Otherwise
                                    * track the channel with the lowest rssi and
                                    * use that when all channels appear occupied.
                                    */
                                   if (maxrssi[i] == 0) {
                                           bestchan = i;
                                           break;
                                   }
                                   if (bestchan == -1 ||
                                       maxrssi[i] < maxrssi[bestchan])
                                           bestchan = i;
                           }
                   if (bestchan != -1) {
                           ieee80211_create_ibss(ic, &ic->ic_channels[bestchan]);
                           return;
                   }
                   /* no suitable channel, should not happen */
           }
   #endif /* !IEEE80211_NO_HOSTAP */
   
           /*
            * When manually sequencing the state machine; scan just once
            * regardless of whether we have a candidate or not.  The
            * controlling application is expected to setup state and
            * initiate an association.
            */
           if (ic->ic_roaming == IEEE80211_ROAMING_MANUAL)
                   return;
           /*
            * Automatic sequencing; look for a candidate and
            * if found join the network.
            */
           /* NB: unlocked read should be ok */
           if (TAILQ_FIRST(&nt->nt_node) == NULL) {
                   IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN,
                           "%s: no scan candidate\n", __func__);
     notfound:
                   if (ic->ic_opmode == IEEE80211_M_IBSS &&
                       (ic->ic_flags & IEEE80211_F_IBSSON) &&
                       ic->ic_des_esslen != 0) {
                           ieee80211_create_ibss(ic, ic->ic_ibss_chan);
                           return;
                   }
                   /*
                    * Decrement the failure counts so entries will be
                    * reconsidered the next time around.  We really want
                    * to do this only for sta's where we've previously
                    * had some success.
                    */
                   IEEE80211_NODE_LOCK(nt);
                   TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
                           if (ni->ni_fails)
                                   ni->ni_fails--;
                   IEEE80211_NODE_UNLOCK(nt);
                   /*
                    * Reset the list of channels to scan and start again.
                    */
                   ieee80211_reset_scan(ic);
                   ic->ic_flags |= IEEE80211_F_SCAN;
                   ieee80211_next_scan(ic);
                   return;
           }
           selbs = NULL;
           IEEE80211_DPRINTF(ic, IEEE80211_MSG_SCAN, "\t%s\n",
               "macaddr          bssid         chan  rssi rate flag  wep  essid");
           IEEE80211_NODE_LOCK(nt);
           TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                   if (ieee80211_match_bss(ic, ni) == 0) {
                           if (selbs == NULL)
                                   selbs = ni;
                           else if (ieee80211_node_compare(ic, ni, selbs) > 0)
                                   selbs = ni;
                   }
           }
           if (selbs != NULL)              /* NB: grab ref while dropping lock */
                   (void) ieee80211_ref_node(selbs);
           IEEE80211_NODE_UNLOCK(nt);
           if (selbs == NULL)
                   goto notfound;
           if (!ieee80211_sta_join(ic, selbs)) {
                   ieee80211_free_node(selbs);
                   goto notfound;
           }
   }
    
   /*
    * Handle 802.11 ad hoc network merge.  The
    * convention, set by the Wireless Ethernet Compatibility Alliance
    * (WECA), is that an 802.11 station will change its BSSID to match
    * the "oldest" 802.11 ad hoc network, on the same channel, that
    * has the station's desired SSID.  The "oldest" 802.11 network
    * sends beacons with the greatest TSF timestamp.
    *
    * The caller is assumed to validate TSF's before attempting a merge.
    *
    * Return !0 if the BSSID changed, 0 otherwise.
    */
   int
   ieee80211_ibss_merge(struct ieee80211_node *ni)
   {
           struct ieee80211com *ic = ni->ni_ic;
   
           if (ni == ic->ic_bss ||
               IEEE80211_ADDR_EQ(ni->ni_bssid, ic->ic_bss->ni_bssid)) {
                   /* unchanged, nothing to do */
                   return 0;
           }
           if (ieee80211_match_bss(ic, ni) != 0) { /* capabilities mismatch */
                   IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                       "%s: merge failed, capabilities mismatch\n", __func__);
                   ic->ic_stats.is_ibss_capmismatch++;
                   return 0;
           }
           if (!ieee80211_sta_join(ic, ieee80211_ref_node(ni)))
                   return 0;
           IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                   "%s: new bssid %s: %s preamble, %s slot time%s\n", __func__,
                   ether_sprintf(ni->ni_bssid),
                   ic->ic_flags&IEEE80211_F_SHPREAMBLE ? "short" : "long",
                   ic->ic_flags&IEEE80211_F_SHSLOT ? "short" : "long",
                   ic->ic_flags&IEEE80211_F_USEPROT ? ", protection" : ""
           );
           ic->ic_flags &= ~IEEE80211_F_SIBSS;
           return 1;
   }
   
   /*
    * Join the specified IBSS/BSS network.  The node is assumed to
    * be passed in with a held reference.
    */
   int
   ieee80211_sta_join(struct ieee80211com *ic, struct ieee80211_node *selbs)
   {
           struct ieee80211_node *obss;
   
           if (ic->ic_opmode == IEEE80211_M_IBSS) {
                   struct ieee80211_node_table *nt;
                   /*
                    * Delete unusable rates; we've already checked
                    * that the negotiated rate set is acceptable.
                    */
                   ieee80211_fix_rate(selbs, IEEE80211_F_DODEL);
                   /*
                    * Fillin the neighbor table; it will already
                    * exist if we are simply switching mastership.
                    * XXX ic_sta always setup so this is unnecessary?
                    */
                   nt = &ic->ic_sta;
                   IEEE80211_NODE_LOCK(nt);
                   nt->nt_name = "neighbor";
                   nt->nt_inact_init = ic->ic_inact_run;
                   IEEE80211_NODE_UNLOCK(nt);
           }
   
           /*
            * Committed to selbs, setup state.
            */
           obss = ic->ic_bss;
           ic->ic_bss = selbs;             /* NB: caller assumed to bump refcnt */
           if (obss != NULL) {
                   copy_bss(selbs, obss);
                   ieee80211_free_node(obss);
           }
           /*
            * Set the erp state (mostly the slot time) to deal with
            * the auto-select case; this should be redundant if the
            * mode is locked.
            */ 
           ic->ic_curmode = ieee80211_chan2mode(ic, selbs->ni_chan);
           ic->ic_curchan = selbs->ni_chan;
           ieee80211_reset_erp(ic);
           ieee80211_wme_initparams(ic);
   
           if (ic->ic_opmode == IEEE80211_M_STA)
                   ieee80211_new_state(ic, IEEE80211_S_AUTH, -1);
           else
                   ieee80211_new_state(ic, IEEE80211_S_RUN, -1);
           return 1;
   }
   
   /*
    * Leave the specified IBSS/BSS network.  The node is assumed to
    * be passed in with a held reference.
    */
   void
   ieee80211_sta_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
   {
           ic->ic_node_cleanup(ni);
           ieee80211_notify_node_leave(ic, ni);
   }
   
   int
   ieee80211_get_rate(const struct ieee80211_node * const ni)
   {
   #define RATE(_ix)       (ni->ni_rates.rs_rates[(_ix)] & IEEE80211_RATE_VAL)
           int ix, rate;
           struct ieee80211com *ic = ni->ni_ic;
           const struct ieee80211_rateset *rs;
   
           IASSERT(ni != NULL, ("ni != NULL"));
           IASSERT(ieee80211_node_refcnt(ni) > 0,
               ("refcnt(ni) == %d", ieee80211_node_refcnt(ni)));
           IASSERT(ic != NULL, ("ic != NULL"));
           if (ic->ic_fixed_rate != IEEE80211_FIXED_RATE_NONE) {
                   rs = &ic->ic_sup_rates[ic->ic_curmode];
                   rate = rs->rs_rates[ic->ic_fixed_rate] & IEEE80211_RATE_VAL;
                   for (ix = ni->ni_rates.rs_nrates - 1;
                        ix >= 0 && RATE(ix) != rate; ix--)
                           ;
                   if (ix < 0) {
                           IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG,
                               "%s: fixed rate %d (%d.%d Mb/s) not in rate set",
                               __func__, ic->ic_fixed_rate, (rate * 5) / 10,
                               (rate * 5) % 10);
                           goto no_rate;
                   }
           } else if (ic->ic_state == IEEE80211_S_RUN)
                   rate = ni->ni_rates.rs_rates[ni->ni_txrate];
           else {
   no_rate:
                   rs = &ni->ni_rates;
                   /* Choose node's lowest basic rate, or else its lowest rate. */
                   for (ix = 0; ix < rs->rs_nrates; ix++) {
                           if (rs->rs_rates[ix] & IEEE80211_RATE_BASIC)
                                   return rs->rs_rates[ix] & IEEE80211_RATE_VAL;
                   }
                   return ni->ni_rates.rs_rates[0] & IEEE80211_RATE_VAL;
           }
           return rate & IEEE80211_RATE_VAL;
   }
   
   static struct ieee80211_node *
   node_alloc(struct ieee80211_node_table *nt)
   {
           struct ieee80211_node *ni;
   
           MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node),
                   M_80211_NODE, M_NOWAIT | M_ZERO);
           return ni;
   }
   
   /*
    * Reclaim any resources in a node and reset any critical
    * state.  Typically nodes are free'd immediately after,
    * but in some cases the storage may be reused so we need
    * to insure consistent state (should probably fix that).
    */
   static void
   node_cleanup(struct ieee80211_node *ni)
   {
   #define N(a)    (sizeof(a)/sizeof(a[0]))
           struct ieee80211com *ic = ni->ni_ic;
           int i, qlen;
   
           /* NB: preserve ni_table */
           if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) {
                   ic->ic_ps_sta--;
                   ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT;
                   IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
                       "[%s] power save mode off, %u sta's in ps mode\n",
                       ether_sprintf(ni->ni_macaddr), ic->ic_ps_sta);
           }
           /*
            * Clear AREF flag that marks the authorization refcnt bump
            * has happened.  This is probably not needed as the node
            * should always be removed from the table so not found but
            * do it just in case.
            */
           ni->ni_flags &= ~IEEE80211_NODE_AREF;
   
           /*
            * Drain power save queue and, if needed, clear TIM.
            */
           IEEE80211_NODE_SAVEQ_DRAIN(ni, qlen);
           if (qlen != 0 && ic->ic_set_tim != NULL)
                   ic->ic_set_tim(ni, 0);
   
           ni->ni_associd = 0;
           if (ni->ni_challenge != NULL) {
                   FREE(ni->ni_challenge, M_DEVBUF);
                   ni->ni_challenge = NULL;
           }
           /*
            * Preserve SSID, WPA, and WME ie's so the bss node is
            * reusable during a re-auth/re-assoc state transition.
            * If we remove these data they will not be recreated
            * because they come from a probe-response or beacon frame
            * which cannot be expected prior to the association-response.
            * This should not be an issue when operating in other modes
            * as stations leaving always go through a full state transition
            * which will rebuild this state.
            *
            * XXX does this leave us open to inheriting old state?
            */
           for (i = 0; i < N(ni->ni_rxfrag); i++)
                   if (ni->ni_rxfrag[i] != NULL) {
                           m_freem(ni->ni_rxfrag[i]);
                           ni->ni_rxfrag[i] = NULL;
                   }
           /*
            * Must be careful here to remove any key map entry w/o a LOR.
            */
           ieee80211_node_delucastkey(ni);
   #undef N
   }
   
   static void
   node_free(struct ieee80211_node *ni)
   {
           struct ieee80211com *ic = ni->ni_ic;
   
           ic->ic_node_cleanup(ni);
           if (ni->ni_wpa_ie != NULL)
                   FREE(ni->ni_wpa_ie, M_DEVBUF);
           if (ni->ni_wme_ie != NULL)
                   FREE(ni->ni_wme_ie, M_DEVBUF);
           IEEE80211_NODE_SAVEQ_DESTROY(ni);
           FREE(ni, M_80211_NODE);
  }
  
  static u_int8_t
  node_getrssi(const struct ieee80211_node *ni)
  {
          return ni->ni_rssi;
  }
  
  static void
  ieee80211_setup_node(struct ieee80211_node_table *nt,
          struct ieee80211_node *ni, const u_int8_t *macaddr)
  {
          struct ieee80211com *ic = nt->nt_ic;
          int hash;
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                  "%s %p<%s> in %s table\n", __func__, ni,
                  ether_sprintf(macaddr), nt->nt_name);
  
          IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
          hash = IEEE80211_NODE_HASH(macaddr);
          ieee80211_node_initref(ni);             /* mark referenced */
          ni->ni_chan = IEEE80211_CHAN_ANYC;
          ni->ni_authmode = IEEE80211_AUTH_OPEN;
          ni->ni_txpower = ic->ic_txpowlimit;     /* max power */
          ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey, IEEE80211_KEYIX_NONE);
          ni->ni_inact_reload = nt->nt_inact_init;
          ni->ni_inact = ni->ni_inact_reload;
          IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
  
          IEEE80211_NODE_LOCK(nt);
          TAILQ_INSERT_TAIL(&nt->nt_node, ni, ni_list);
          LIST_INSERT_HEAD(&nt->nt_hash[hash], ni, ni_hash);
          ni->ni_table = nt;
          ni->ni_ic = ic;
          IEEE80211_NODE_UNLOCK(nt);
  }
  
  struct ieee80211_node *
  ieee80211_alloc_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
  
          ni = ic->ic_node_alloc(nt);
          if (ni != NULL)
                  ieee80211_setup_node(nt, ni, macaddr);
          else
                  ic->ic_stats.is_rx_nodealloc++;
          return ni;
  }
  
  /*
   * Craft a temporary node suitable for sending a management frame
   * to the specified station.  We craft only as much state as we
   * need to do the work since the node will be immediately reclaimed
   * once the send completes.
   */
  struct ieee80211_node *
  ieee80211_tmp_node(struct ieee80211com *ic, const u_int8_t *macaddr)
  {
          struct ieee80211_node *ni;
  
          ni = ic->ic_node_alloc(&ic->ic_sta);
          if (ni != NULL) {
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                          "%s %p<%s>\n", __func__, ni, ether_sprintf(macaddr));
  
                  IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr);
                  IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
                  ieee80211_node_initref(ni);             /* mark referenced */
                  ni->ni_txpower = ic->ic_bss->ni_txpower;
                  /* NB: required by ieee80211_fix_rate */
                  ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
                  ieee80211_crypto_resetkey(ic, &ni->ni_ucastkey,
                          IEEE80211_KEYIX_NONE);
                  /* XXX optimize away */
                  IEEE80211_NODE_SAVEQ_INIT(ni, "unknown");
  
                  ni->ni_table = NULL;            /* NB: pedantic */
                  ni->ni_ic = ic;
          } else {
                  /* XXX msg */
                  ic->ic_stats.is_rx_nodealloc++;
          }
          return ni;
  }
  
  struct ieee80211_node *
  ieee80211_dup_bss(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
  
          ni = ic->ic_node_alloc(nt);
          if (ni != NULL) {
                  ieee80211_setup_node(nt, ni, macaddr);
                  /*
                   * Inherit from ic_bss.
                   */
                  ni->ni_authmode = ic->ic_bss->ni_authmode;
                  ni->ni_txpower = ic->ic_bss->ni_txpower;
                  ni->ni_vlan = ic->ic_bss->ni_vlan;      /* XXX?? */
                  IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid);
                  ieee80211_set_chan(ic, ni, ic->ic_bss->ni_chan);
                  ni->ni_rsn = ic->ic_bss->ni_rsn;
          } else
                  ic->ic_stats.is_rx_nodealloc++;
          return ni;
  }
  
  static struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  _ieee80211_find_node_debug(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, const char *func, int line)
  #else
  _ieee80211_find_node(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr)
  #endif
  {
          struct ieee80211_node *ni;
          int hash;
  
          IEEE80211_NODE_LOCK_ASSERT(nt);
  
          hash = IEEE80211_NODE_HASH(macaddr);
          LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
                  if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) {
                          ieee80211_ref_node(ni); /* mark referenced */
  #ifdef IEEE80211_DEBUG_REFCNT
                          IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
                              "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
                              func, line,
                              ni, ether_sprintf(ni->ni_macaddr),
                              ieee80211_node_refcnt(ni));
  #endif
                          return ni;
                  }
          }
          return NULL;
  }
  #ifdef IEEE80211_DEBUG_REFCNT
  #define _ieee80211_find_node(nt, mac) \
          _ieee80211_find_node_debug(nt, mac, func, line)
  #endif
  
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_node_debug(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, const char *func, int line)
  #else
  ieee80211_find_node(struct ieee80211_node_table *nt, const u_int8_t *macaddr)
  #endif
  {
          struct ieee80211_node *ni;
  
          IEEE80211_NODE_LOCK(nt);
          ni = _ieee80211_find_node(nt, macaddr);
          IEEE80211_NODE_UNLOCK(nt);
          return ni;
  }
  
  /*
   * Fake up a node; this handles node discovery in adhoc mode.
   * Note that for the driver's benefit we we treat this like
   * an association so the driver has an opportunity to setup
   * it's private state.
   */
  struct ieee80211_node *
  ieee80211_fakeup_adhoc_node(struct ieee80211_node_table *nt,
          const u_int8_t macaddr[IEEE80211_ADDR_LEN])
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
  
          ni = ieee80211_dup_bss(nt, macaddr);
          if (ni != NULL) {
                  /* XXX no rate negotiation; just dup */
                  ni->ni_rates = ic->ic_bss->ni_rates;
                  if (ic->ic_newassoc != NULL)
                          ic->ic_newassoc(ni, 1);
                  /* XXX not right for 802.1x/WPA */
                  ieee80211_node_authorize(ni);
          }
          return ni;
  }
  
  #ifdef IEEE80211_DEBUG
  static void
  dump_probe_beacon(u_int8_t subtype, int isnew,
          const u_int8_t mac[IEEE80211_ADDR_LEN],
          const struct ieee80211_scanparams *sp)
  {
  
          printf("[%s] %s%s on chan %u (bss chan %u) ",
              ether_sprintf(mac), isnew ? "new " : "",
              ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT],
              sp->chan, sp->bchan);
          ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
          printf("\n");
  
          if (isnew) {
                  printf("[%s] caps 0x%x bintval %u erp 0x%x", 
                          ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
                  if (sp->country != NULL) {
  #ifdef __FreeBSD__
                          printf(" country info %*D",
                                  sp->country[1], sp->country+2, " ");
  #else
                          int i;
                          printf(" country info");
                          for (i = 0; i < sp->country[1]; i++)
                                  printf(" %02x", sp->country[i+2]);
  #endif
                  }
                  printf("\n");
          }
  }
  #endif /* IEEE80211_DEBUG */
  
  static void
  saveie(u_int8_t **iep, const u_int8_t *ie)
  {
  
          if (ie == NULL)
                  *iep = NULL;
          else
                  ieee80211_saveie(iep, ie);
  }
  
  /*
   * Process a beacon or probe response frame.
   */
  void
  ieee80211_add_scan(struct ieee80211com *ic,
          const struct ieee80211_scanparams *sp,
          const struct ieee80211_frame *wh,
          int subtype, int rssi, int rstamp)
  {
  #define ISPROBE(_st)    ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
          struct ieee80211_node_table *nt = &ic->ic_scan;
          struct ieee80211_node *ni;
          int newnode = 0;
  
          ni = ieee80211_find_node(nt, wh->i_addr2);
          if (ni == NULL) {
                  /*
                   * Create a new entry.
                   */
                  ni = ic->ic_node_alloc(nt);
                  if (ni == NULL) {
                          ic->ic_stats.is_rx_nodealloc++;
                          return;
                  }
                  ieee80211_setup_node(nt, ni, wh->i_addr2);
                  /*
                   * XXX inherit from ic_bss.
                   */
                  ni->ni_authmode = ic->ic_bss->ni_authmode;
                  ni->ni_txpower = ic->ic_bss->ni_txpower;
                  ni->ni_vlan = ic->ic_bss->ni_vlan;      /* XXX?? */
                  ieee80211_set_chan(ic, ni, ic->ic_curchan);
                  ni->ni_rsn = ic->ic_bss->ni_rsn;
                  newnode = 1;
          }
  #ifdef IEEE80211_DEBUG
          if (ieee80211_msg_scan(ic) && (ic->ic_flags & IEEE80211_F_SCAN))
                  dump_probe_beacon(subtype, newnode, wh->i_addr2, sp);
  #endif
          /* XXX ap beaconing multiple ssid w/ same bssid */
          if (sp->ssid[1] != 0 &&
              (ISPROBE(subtype) || ni->ni_esslen == 0)) {
                  ni->ni_esslen = sp->ssid[1];
                  memset(ni->ni_essid, 0, sizeof(ni->ni_essid));
                  memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
          }
          ni->ni_scangen = ic->ic_scan.nt_scangen;
          IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
          ni->ni_rssi = rssi;
          ni->ni_rstamp = rstamp;
          memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
          ni->ni_intval = sp->bintval;
          ni->ni_capinfo = sp->capinfo;
          ni->ni_chan = &ic->ic_channels[sp->chan];
          ni->ni_fhdwell = sp->fhdwell;
          ni->ni_fhindex = sp->fhindex;
          ni->ni_erp = sp->erp;
          if (sp->tim != NULL) {
                  struct ieee80211_tim_ie *ie =
                      (struct ieee80211_tim_ie *) sp->tim;
  
                  ni->ni_dtim_count = ie->tim_count;
                  ni->ni_dtim_period = ie->tim_period;
          }
          /*
           * Record the byte offset from the mac header to
           * the start of the TIM information element for
           * use by hardware and/or to speedup software
           * processing of beacon frames.
           */
          ni->ni_timoff = sp->timoff;
          /*
           * Record optional information elements that might be
           * used by applications or drivers.
           */
          saveie(&ni->ni_wme_ie, sp->wme);
          saveie(&ni->ni_wpa_ie, sp->wpa);
  
          /* NB: must be after ni_chan is setup */
          ieee80211_setup_rates(ni, sp->rates, sp->xrates, IEEE80211_F_DOSORT);
  
          if (!newnode)
                  ieee80211_free_node(ni);
  #undef ISPROBE
  }
  
  void
  ieee80211_init_neighbor(struct ieee80211com *ic, struct ieee80211_node *ni,
      const struct ieee80211_frame *wh, const struct ieee80211_scanparams *sp,
      int isnew)
  {
          ni->ni_esslen = sp->ssid[1];
          memcpy(ni->ni_essid, sp->ssid + 2, sp->ssid[1]);
          IEEE80211_ADDR_COPY(ni->ni_bssid, wh->i_addr3);
          memcpy(ni->ni_tstamp.data, sp->tstamp, sizeof(ni->ni_tstamp));
          ni->ni_intval = sp->bintval;
          ni->ni_capinfo = sp->capinfo;
          ni->ni_chan = ic->ic_bss->ni_chan;
          ni->ni_fhdwell = sp->fhdwell;
          ni->ni_fhindex = sp->fhindex;
          ni->ni_erp = sp->erp;
          ni->ni_timoff = sp->timoff;
          if (sp->wme != NULL)
                  ieee80211_saveie(&ni->ni_wme_ie, sp->wme);
          if (sp->wpa != NULL)
                  ieee80211_saveie(&ni->ni_wpa_ie, sp->wpa);
  
          /* NB: must be after ni_chan is setup */
          ieee80211_setup_rates(ni, sp->rates, sp->xrates,
              IEEE80211_F_DODEL | IEEE80211_F_DONEGO | IEEE80211_F_DOSORT);
  
          if (ic->ic_newassoc != NULL)
                  ic->ic_newassoc(ni, isnew);
  }
  
  /*
   * Do node discovery in adhoc mode on receipt of a beacon
   * or probe response frame.  Note that for the driver's
   * benefit we we treat this like an association so the
   * driver has an opportunity to setup it's private state.
   */
  struct ieee80211_node *
  ieee80211_add_neighbor(struct ieee80211com *ic,
          const struct ieee80211_frame *wh,
          const struct ieee80211_scanparams *sp)
  {
          struct ieee80211_node *ni;
  
          ni = ieee80211_dup_bss(&ic->ic_sta, wh->i_addr2);/* XXX alloc_node? */
          if (ni != NULL) {
                  ieee80211_init_neighbor(ic, ni, wh, sp, 1);
                  /* XXX not right for 802.1x/WPA */
                  ieee80211_node_authorize(ni);
          }
          return ni;
  }
  
  #define IS_CTL(wh) \
          ((wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_CTL)
  #define IS_PSPOLL(wh) \
          ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
  /*
   * Locate the node for sender, track state, and then pass the
   * (referenced) node up to the 802.11 layer for its use.  We
   * are required to pass some node so we fall back to ic_bss
   * when this frame is from an unknown sender.  The 802.11 layer
   * knows this means the sender wasn't in the node table and
   * acts accordingly. 
   */
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_rxnode_debug(struct ieee80211com *ic,
          const struct ieee80211_frame_min *wh, const char *func, int line)
  #else
  ieee80211_find_rxnode(struct ieee80211com *ic,
          const struct ieee80211_frame_min *wh)
  #endif
  {
          struct ieee80211_node_table *nt;
          struct ieee80211_node *ni;
  
          /* XXX may want scanned nodes in the neighbor table for adhoc */
          if (ic->ic_opmode == IEEE80211_M_STA ||
              ic->ic_opmode == IEEE80211_M_MONITOR ||
              (ic->ic_flags & IEEE80211_F_SCAN))
                  nt = &ic->ic_scan;
          else
                  nt = &ic->ic_sta;
          /* XXX check ic_bss first in station mode */
          /* XXX 4-address frames? */
          IEEE80211_NODE_LOCK(nt);
          if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
                  ni = _ieee80211_find_node(nt, wh->i_addr1);
          else
                  ni = _ieee80211_find_node(nt, wh->i_addr2);
          if (ni == NULL)
                  ni = ieee80211_ref_node(ic->ic_bss);
          IEEE80211_NODE_UNLOCK(nt);
  
          return ni;
  }
  
  /*
   * Like ieee80211_find_rxnode but use the supplied h/w
   * key index as a hint to locate the node in the key
   * mapping table.  If an entry is present at the key
   * index we return it; otherwise do a normal lookup and
   * update the mapping table if the station has a unicast
   * key assigned to it.
   */
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_rxnode_withkey_debug(struct ieee80211com *ic,
          const struct ieee80211_frame_min *wh, ieee80211_keyix keyix,
          const char *func, int line)
  #else
  ieee80211_find_rxnode_withkey(struct ieee80211com *ic,
          const struct ieee80211_frame_min *wh, ieee80211_keyix keyix)
  #endif
  {
          struct ieee80211_node_table *nt;
          struct ieee80211_node *ni;
  
          if (ic->ic_opmode == IEEE80211_M_STA ||
              ic->ic_opmode == IEEE80211_M_MONITOR ||
              (ic->ic_flags & IEEE80211_F_SCAN))
                  nt = &ic->ic_scan;
          else
                  nt = &ic->ic_sta;
          IEEE80211_NODE_LOCK(nt);
          if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax)
                  ni = nt->nt_keyixmap[keyix];
          else
                  ni = NULL;
          if (ni == NULL) {
                  if (IS_CTL(wh) && !IS_PSPOLL(wh) /*&& !IS_RTS(ah)*/)
                          ni = _ieee80211_find_node(nt, wh->i_addr1);
                  else
                          ni = _ieee80211_find_node(nt, wh->i_addr2);
                  if (ni == NULL)
                          ni = ieee80211_ref_node(ic->ic_bss);
                  if (nt->nt_keyixmap != NULL) {
                          /*
                           * If the station has a unicast key cache slot
                           * assigned update the key->node mapping table.
                           */
                          keyix = ni->ni_ucastkey.wk_rxkeyix;
                          /* XXX can keyixmap[keyix] != NULL? */
                          if (keyix < nt->nt_keyixmax &&
                              nt->nt_keyixmap[keyix] == NULL) {
                                  IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                                      "%s: add key map entry %p<%s> refcnt %d\n",
                                      __func__, ni, ether_sprintf(ni->ni_macaddr),
                                      ieee80211_node_refcnt(ni)+1);
                                  nt->nt_keyixmap[keyix] = ieee80211_ref_node(ni);
                          }
                  }
          } else {
                  ieee80211_ref_node(ni);
          }
          IEEE80211_NODE_UNLOCK(nt);
  
          return ni;
  }
  #undef IS_PSPOLL
  #undef IS_CTL
  
  /*
   * Return a reference to the appropriate node for sending
   * a data frame.  This handles node discovery in adhoc networks.
   */
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_txnode_debug(struct ieee80211com *ic, const u_int8_t *macaddr,
          const char *func, int line)
  #else
  ieee80211_find_txnode(struct ieee80211com *ic, const u_int8_t *macaddr)
  #endif
  {
          struct ieee80211_node_table *nt = &ic->ic_sta;
          struct ieee80211_node *ni;
  
          /*
           * The destination address should be in the node table
           * unless this is a multicast/broadcast frame.  We can
           * also optimize station mode operation, all frames go
           * to the bss node.
           */
          /* XXX can't hold lock across dup_bss 'cuz of recursive locking */
          IEEE80211_NODE_LOCK(nt);
          if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr))
                  ni = ieee80211_ref_node(ic->ic_bss);
          else
                  ni = _ieee80211_find_node(nt, macaddr);
          IEEE80211_NODE_UNLOCK(nt);
  
          if (ni == NULL) {
                  if (ic->ic_opmode == IEEE80211_M_IBSS ||
                      ic->ic_opmode == IEEE80211_M_AHDEMO) {
                          /*
                           * In adhoc mode cons up a node for the destination.
                           * Note that we need an additional reference for the
                           * caller to be consistent with _ieee80211_find_node.
                           */
                          ni = ieee80211_fakeup_adhoc_node(nt, macaddr);
                          if (ni != NULL)
                                  (void) ieee80211_ref_node(ni);
                  } else {
                          IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
                                  "[%s] no node, discard frame (%s)\n",
                                  ether_sprintf(macaddr), __func__);
                          ic->ic_stats.is_tx_nonode++;
                  }
          }
          return ni;
  }
  
  /*
   * Like find but search based on the channel too.
   */
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_node_with_channel_debug(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, struct ieee80211_channel *chan,
          const char *func, int line)
  #else
  ieee80211_find_node_with_channel(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, struct ieee80211_channel *chan)
  #endif
  {
          struct ieee80211_node *ni;
          int hash;
  
          hash = IEEE80211_NODE_HASH(macaddr);
          IEEE80211_NODE_LOCK(nt);
          LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
                  if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
                      ni->ni_chan == chan) {
                          ieee80211_ref_node(ni);         /* mark referenced */
  #ifdef IEEE80211_DEBUG_REFCNT
                          IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
                              "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
                              func, line,
                              ni, ether_sprintf(ni->ni_macaddr),
                              ieee80211_node_refcnt(ni));
  #else
                          IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
                              "%s %p<%s> refcnt %d\n", __func__,
                              ni, ether_sprintf(ni->ni_macaddr),
                              ieee80211_node_refcnt(ni));
  #endif
                          break;
                  }
          }
          IEEE80211_NODE_UNLOCK(nt);
          return ni;
  }
  
  struct ieee80211_node *
  ieee80211_refine_node_for_beacon(struct ieee80211com *ic,
          struct ieee80211_node *ni0, struct ieee80211_channel *chan,
          const u_int8_t *ssid)
  {
          struct ieee80211_node_table *nt = ni0->ni_table;
          struct ieee80211_node *best, *ni;
          int best_score = 0, score;
  
          if (nt == NULL)
                  return ni0;
  
          best = ni0;
          if (ssid[1] == 0 || best->ni_esslen == 0)
                  best_score = 1;
          else if (ssid[1] == best->ni_esslen &&
                   memcmp(ssid + 2, best->ni_essid, ssid[1]) == 0)
                  best_score = 2;
          else
                  best_score = 0;
  
          IEEE80211_NODE_LOCK(nt);
          for (ni = LIST_NEXT(ni0, ni_hash); ni != NULL;
               ni = LIST_NEXT(ni, ni_hash)) {
                  if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, best->ni_macaddr) ||
                      ni->ni_ic != best->ni_ic || ni->ni_chan != chan)
                          continue;
  
                  if (ssid[1] == 0 || ni->ni_esslen == 0)
                          score = 1;
                  else if (ssid[1] == ni->ni_esslen &&
                           memcmp(ssid + 2, ni->ni_essid, ssid[1]) == 0)
                          score = 2;
                  else
                          continue;
  
                  if (score > best_score) {
                          best = ni;
                          best_score = score;
                  }
          }
          IEEE80211_NODE_UNLOCK(nt);
          return best;
  }
  
  /*
   * Like find but search based on the ssid too.
   */
  struct ieee80211_node *
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_find_node_with_ssid_debug(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid,
          const char *func, int line)
  #else
  ieee80211_find_node_with_ssid(struct ieee80211_node_table *nt,
          const u_int8_t *macaddr, u_int ssidlen, const u_int8_t *ssid)
  #endif
  {
  #define MATCH_SSID(ni, ssid, ssidlen) \
          (ni->ni_esslen == ssidlen && memcmp(ni->ni_essid, ssid, ssidlen) == 0)
          static const u_int8_t zeromac[IEEE80211_ADDR_LEN];
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
          int hash;
  
          IEEE80211_NODE_LOCK(nt);
          /*
           * A mac address that is all zero means match only the ssid;
           * otherwise we must match both.
           */
          if (IEEE80211_ADDR_EQ(macaddr, zeromac)) {
                  TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                          if (MATCH_SSID(ni, ssid, ssidlen))
                                  break;
                  }
          } else {
                  hash = IEEE80211_NODE_HASH(macaddr);
                  LIST_FOREACH(ni, &nt->nt_hash[hash], ni_hash) {
                          if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr) &&
                              MATCH_SSID(ni, ssid, ssidlen))
                                  break;
                  }
          }
          if (ni != NULL) {
                  ieee80211_ref_node(ni); /* mark referenced */
  #ifdef IEEE80211_DEBUG_REFCNT
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                      "%s (%s:%u) %p<%s> refcnt %d\n", __func__,
                      func, line,
                       ni, ether_sprintf(ni->ni_macaddr),
                       ieee80211_node_refcnt(ni));
  #else
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                      "%s %p<%s> refcnt %d\n", __func__,
                       ni, ether_sprintf(ni->ni_macaddr),
                       ieee80211_node_refcnt(ni));
  #endif
          }
          IEEE80211_NODE_UNLOCK(nt);
          return ni;
  #undef MATCH_SSID
  }
  
  static void
  _ieee80211_free_node(struct ieee80211_node *ni)
  {
          struct ieee80211com *ic = ni->ni_ic;
          struct ieee80211_node_table *nt = ni->ni_table;
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                  "%s %p<%s> in %s table\n", __func__, ni,
                  ether_sprintf(ni->ni_macaddr),
                  nt != NULL ? nt->nt_name : "<gone>");
  
          IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
          if (nt != NULL) {
                  TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
                  LIST_REMOVE(ni, ni_hash);
          }
          ic->ic_node_free(ni);
  }
  
  void
  #ifdef IEEE80211_DEBUG_REFCNT
  ieee80211_free_node_debug(struct ieee80211_node *ni, const char *func, int line)
  #else
  ieee80211_free_node(struct ieee80211_node *ni)
  #endif
  {
          struct ieee80211_node_table *nt = ni->ni_table;
  
  #ifdef IEEE80211_DEBUG_REFCNT
          IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                  "%s (%s:%u) %p<%s> refcnt %d\n", __func__, func, line, ni,
                   ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni)-1);
  #endif
          if (nt != NULL) {
                  IEEE80211_NODE_LOCK(nt);
                  if (ieee80211_node_dectestref(ni)) {
                          /*
                           * Last reference, reclaim state.
                           */
                          _ieee80211_free_node(ni);
                  } else if (ieee80211_node_refcnt(ni) == 1 &&
                      nt->nt_keyixmap != NULL) {
                          ieee80211_keyix keyix;
                          /*
                           * Check for a last reference in the key mapping table.
                           */
                          keyix = ni->ni_ucastkey.wk_rxkeyix;
                          if (keyix < nt->nt_keyixmax &&
                              nt->nt_keyixmap[keyix] == ni) {
                                  IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                                      "%s: %p<%s> clear key map entry", __func__,
                                      ni, ether_sprintf(ni->ni_macaddr));
                                  nt->nt_keyixmap[keyix] = NULL;
                                  ieee80211_node_decref(ni); /* XXX needed? */
                                  _ieee80211_free_node(ni);
                          }
                  }
                  IEEE80211_NODE_UNLOCK(nt);
          } else {
                  if (ieee80211_node_dectestref(ni))
                          _ieee80211_free_node(ni);
          }
  }
  
  /*
   * Reclaim a unicast key and clear any key cache state.
   */
  int
  ieee80211_node_delucastkey(struct ieee80211_node *ni)
  {
          struct ieee80211com *ic = ni->ni_ic;
          struct ieee80211_node_table *nt = &ic->ic_sta;
          struct ieee80211_node *nikey;
          ieee80211_keyix keyix;
          int isowned, status;
  
          /*
           * NB: We must beware of LOR here; deleting the key
           * can cause the crypto layer to block traffic updates
           * which can generate a LOR against the node table lock;
           * grab it here and stash the key index for our use below.
           *
           * Must also beware of recursion on the node table lock.
           * When called from node_cleanup we may already have
           * the node table lock held.  Unfortunately there's no
           * way to separate out this path so we must do this
           * conditionally.
           */
          isowned = IEEE80211_NODE_IS_LOCKED(nt);
          if (!isowned)
                  IEEE80211_NODE_LOCK(nt);
          keyix = ni->ni_ucastkey.wk_rxkeyix;
          status = ieee80211_crypto_delkey(ic, &ni->ni_ucastkey);
          if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax) {
                  nikey = nt->nt_keyixmap[keyix];
                  nt->nt_keyixmap[keyix] = NULL;;
          } else
                  nikey = NULL;
          if (!isowned)
                  IEEE80211_NODE_UNLOCK(&ic->ic_sta);
  
          if (nikey != NULL) {
                  IASSERT(nikey == ni,
                          ("key map out of sync, ni %p nikey %p", ni, nikey));
                  IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                          "%s: delete key map entry %p<%s> refcnt %d\n",
                          __func__, ni, ether_sprintf(ni->ni_macaddr),
                          ieee80211_node_refcnt(ni)-1);
                  ieee80211_free_node(ni);
          }
          return status;
  }
  
  /*
   * Reclaim a node.  If this is the last reference count then
   * do the normal free work.  Otherwise remove it from the node
   * table and mark it gone by clearing the back-reference.
   */
  static void
  node_reclaim(struct ieee80211_node_table *nt, struct ieee80211_node *ni)
  {
          ieee80211_keyix keyix;
  
          IEEE80211_NODE_LOCK_ASSERT(nt);
  
          IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                  "%s: remove %p<%s> from %s table, refcnt %d\n",
                  __func__, ni, ether_sprintf(ni->ni_macaddr),
                  nt->nt_name, ieee80211_node_refcnt(ni)-1);
          /*
           * Clear any entry in the unicast key mapping table.
           * We need to do it here so rx lookups don't find it
           * in the mapping table even if it's not in the hash
           * table.  We cannot depend on the mapping table entry
           * being cleared because the node may not be free'd.
           */
          keyix = ni->ni_ucastkey.wk_rxkeyix;
          if (nt->nt_keyixmap != NULL && keyix < nt->nt_keyixmax &&
              nt->nt_keyixmap[keyix] == ni) {
                  IEEE80211_DPRINTF(ni->ni_ic, IEEE80211_MSG_NODE,
                          "%s: %p<%s> clear key map entry\n",
                          __func__, ni, ether_sprintf(ni->ni_macaddr));
                  nt->nt_keyixmap[keyix] = NULL;
                  ieee80211_node_decref(ni);      /* NB: don't need free */
          }
          if (!ieee80211_node_dectestref(ni)) {
                  /*
                   * Other references are present, just remove the
                   * node from the table so it cannot be found.  When
                   * the references are dropped storage will be
                   * reclaimed.
                   */
                  TAILQ_REMOVE(&nt->nt_node, ni, ni_list);
                  LIST_REMOVE(ni, ni_hash);
                  ni->ni_table = NULL;            /* clear reference */
          } else
                  _ieee80211_free_node(ni);
  }
  
  static void
  ieee80211_free_allnodes_locked(struct ieee80211_node_table *nt)
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                  "%s: free all nodes in %s table\n", __func__, nt->nt_name);
  
          while ((ni = TAILQ_FIRST(&nt->nt_node)) != NULL) {
                  if (ni->ni_associd != 0) {
                          if (ic->ic_auth->ia_node_leave != NULL)
                                  ic->ic_auth->ia_node_leave(ic, ni);
                          IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
                  }
                  node_reclaim(nt, ni);
          }
          ieee80211_reset_erp(ic);
  }
  
  static void
  ieee80211_free_allnodes(struct ieee80211_node_table *nt)
  {
  
          IEEE80211_NODE_LOCK(nt);
          ieee80211_free_allnodes_locked(nt);
          IEEE80211_NODE_UNLOCK(nt);
  }
  
  /*
   * Timeout entries in the scan cache.
   */
  static void
  ieee80211_timeout_scan_candidates(struct ieee80211_node_table *nt)
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni, *tni;
  
          IEEE80211_NODE_LOCK(nt);
          ni = ic->ic_bss;
          /* XXX belongs elsewhere */
          if (ni->ni_rxfrag[0] != NULL && ticks > ni->ni_rxfragstamp + hz) {
                  m_freem(ni->ni_rxfrag[0]);
                  ni->ni_rxfrag[0] = NULL;
          }
          TAILQ_FOREACH_SAFE(ni, &nt->nt_node, ni_list, tni) {
                  if (ni->ni_inact && --ni->ni_inact == 0) {
                          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                              "[%s] scan candidate purged from cache "
                              "(refcnt %u)\n", ether_sprintf(ni->ni_macaddr),
                              ieee80211_node_refcnt(ni));
                          node_reclaim(nt, ni);
                  }
          }
          IEEE80211_NODE_UNLOCK(nt);
  
          nt->nt_inact_timer = IEEE80211_INACT_WAIT;
  }
  
  /*
   * Timeout inactive stations and do related housekeeping.
   * Note that we cannot hold the node lock while sending a
   * frame as this would lead to a LOR.  Instead we use a
   * generation number to mark nodes that we've scanned and
   * drop the lock and restart a scan if we have to time out
   * a node.  Since we are single-threaded by virtue of
   * controlling the inactivity timer we can be sure this will
   * process each node only once.
   */
  static void
  ieee80211_timeout_stations(struct ieee80211_node_table *nt)
  {
          struct ieee80211com *ic = nt->nt_ic;
          struct ieee80211_node *ni;
          u_int gen;
          int isadhoc;
  
          isadhoc = (ic->ic_opmode == IEEE80211_M_IBSS ||
                     ic->ic_opmode == IEEE80211_M_AHDEMO);
          IEEE80211_SCAN_LOCK(nt);
          gen = ++nt->nt_scangen;
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                  "%s: %s scangen %u\n", __func__, nt->nt_name, gen);
  restart:
          IEEE80211_NODE_LOCK(nt);
          TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                  if (ni->ni_scangen == gen)      /* previously handled */
                          continue;
                  ni->ni_scangen = gen;
                  /*
                   * Ignore entries for which have yet to receive an
                   * authentication frame.  These are transient and
                   * will be reclaimed when the last reference to them
                   * goes away (when frame xmits complete).
                   */
                  if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
                      (ni->ni_flags & IEEE80211_NODE_AREF) == 0)
                          continue;
                  /*
                   * Free fragment if not needed anymore
                   * (last fragment older than 1s).
                   * XXX doesn't belong here
                   */
                  if (ni->ni_rxfrag[0] != NULL &&
                      ticks > ni->ni_rxfragstamp + hz) {
                          m_freem(ni->ni_rxfrag[0]);
                          ni->ni_rxfrag[0] = NULL;
                  }
                  /*
                   * Special case ourself; we may be idle for extended periods
                   * of time and regardless reclaiming our state is wrong.
                   */
                  if (ni == ic->ic_bss)
                          continue;
                  ni->ni_inact--;
                  if (ni->ni_associd != 0 || isadhoc) {
                          /*
                           * Age frames on the power save queue. The
                           * aging interval is 4 times the listen
                           * interval specified by the station.  This
                           * number is factored into the age calculations
                           * when the frame is placed on the queue.  We
                           * store ages as time differences we can check
                           * and/or adjust only the head of the list.
                           */
                          if (IEEE80211_NODE_SAVEQ_QLEN(ni) != 0) {
                                  struct mbuf *m;
                                  int discard = 0;
  
                                  IEEE80211_NODE_SAVEQ_LOCK(ni);
                                  while (IF_POLL(&ni->ni_savedq, m) != NULL &&
                                       M_AGE_GET(m) < IEEE80211_INACT_WAIT) {
  IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER, "[%s] discard frame, age %u\n", ether_sprintf(ni->ni_macaddr), M_AGE_GET(m));/*XXX*/
                                          _IEEE80211_NODE_SAVEQ_DEQUEUE_HEAD(ni, m);
                                          m_freem(m);
                                          discard++;
                                  }
                                  if (m != NULL)
                                          M_AGE_SUB(m, IEEE80211_INACT_WAIT);
                                  IEEE80211_NODE_SAVEQ_UNLOCK(ni);
  
                                  if (discard != 0) {
                                          IEEE80211_DPRINTF(ic,
                                              IEEE80211_MSG_POWER,
                                              "[%s] discard %u frames for age\n",
                                              ether_sprintf(ni->ni_macaddr),
                                              discard);
                                          IEEE80211_NODE_STAT_ADD(ni,
                                                  ps_discard, discard);
                                          if (IEEE80211_NODE_SAVEQ_QLEN(ni) == 0)
                                                  ic->ic_set_tim(ni, 0);
                                  }
                          }
                          /*
                           * Probe the station before time it out.  We
                           * send a null data frame which may not be
                           * universally supported by drivers (need it
                           * for ps-poll support so it should be...).
                           */
                          if (0 < ni->ni_inact &&
                              ni->ni_inact <= ic->ic_inact_probe) {
                                  IEEE80211_NOTE(ic,
                                      IEEE80211_MSG_INACT | IEEE80211_MSG_NODE,
                                      ni, "%s",
                                      "probe station due to inactivity");
                                  /*
                                   * Grab a reference before unlocking the table
                                   * so the node cannot be reclaimed before we
                                   * send the frame. ieee80211_send_nulldata
                                   * understands we've done this and reclaims the
                                   * ref for us as needed.
                                   */
                                  ieee80211_ref_node(ni);
                                  IEEE80211_NODE_UNLOCK(nt);
                                  ieee80211_send_nulldata(ni);
                                  /* XXX stat? */
                                  goto restart;
                          }
                  }
                  if (ni->ni_inact <= 0) {
                          IEEE80211_NOTE(ic,
                              IEEE80211_MSG_INACT | IEEE80211_MSG_NODE, ni,
                              "station timed out due to inactivity "
                              "(refcnt %u)", ieee80211_node_refcnt(ni));
                          /*
                           * Send a deauthenticate frame and drop the station.
                           * This is somewhat complicated due to reference counts
                           * and locking.  At this point a station will typically
                           * have a reference count of 1.  ieee80211_node_leave
                           * will do a "free" of the node which will drop the
                           * reference count.  But in the meantime a reference
                           * will be held by the deauth frame.  The actual reclaim
                           * of the node will happen either after the tx is
                           * completed or by ieee80211_node_leave.
                           *
                           * Separately we must drop the node lock before sending
                           * in case the driver takes a lock, as this will result
                           * in  LOR between the node lock and the driver lock.
                           */
                          IEEE80211_NODE_UNLOCK(nt);
                          if (ni->ni_associd != 0) {
                                  IEEE80211_SEND_MGMT(ic, ni,
                                      IEEE80211_FC0_SUBTYPE_DEAUTH,
                                      IEEE80211_REASON_AUTH_EXPIRE);
                          }
                          ieee80211_node_leave(ic, ni);
                          ic->ic_stats.is_node_timeout++;
                          goto restart;
                  }
          }
          IEEE80211_NODE_UNLOCK(nt);
  
          IEEE80211_SCAN_UNLOCK(nt);
  
          nt->nt_inact_timer = IEEE80211_INACT_WAIT;
  }
  
  void
  ieee80211_iterate_nodes(struct ieee80211_node_table *nt, ieee80211_iter_func *f, void *arg)
  {
          struct ieee80211_node *ni;
          u_int gen;
  
          IEEE80211_SCAN_LOCK(nt);
          gen = ++nt->nt_scangen;
  restart:
          IEEE80211_NODE_LOCK(nt);
          TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                  if (ni->ni_scangen != gen) {
                          ni->ni_scangen = gen;
                          (void) ieee80211_ref_node(ni);
                          IEEE80211_NODE_UNLOCK(nt);
                          (*f)(arg, ni);
                          ieee80211_free_node(ni);
                          goto restart;
                  }
          }
          IEEE80211_NODE_UNLOCK(nt);
  
          IEEE80211_SCAN_UNLOCK(nt);
  }
  
  void
  ieee80211_dump_node(struct ieee80211_node_table *nt,
      struct ieee80211_node *ni)
  {
          printf("0x%p: mac %s refcnt %d\n", ni,
                  ether_sprintf(ni->ni_macaddr), ieee80211_node_refcnt(ni));
          printf("\tscangen %u authmode %u flags 0x%x\n",
                  ni->ni_scangen, ni->ni_authmode, ni->ni_flags);
          printf("\tassocid 0x%x txpower %u vlan %u\n",
                  ni->ni_associd, ni->ni_txpower, ni->ni_vlan);
          printf("\ttxseq %u rxseq %u fragno %u rxfragstamp %u\n",
                  ni->ni_txseqs[0],
                  ni->ni_rxseqs[0] >> IEEE80211_SEQ_SEQ_SHIFT,
                  ni->ni_rxseqs[0] & IEEE80211_SEQ_FRAG_MASK,
                  ni->ni_rxfragstamp);
          printf("\trstamp %u rssi %u intval %u capinfo 0x%x\n",
                  ni->ni_rstamp, ni->ni_rssi, ni->ni_intval, ni->ni_capinfo);
          printf("\tbssid %s essid \"%.*s\" channel %u:0x%x\n",
                  ether_sprintf(ni->ni_bssid),
                  ni->ni_esslen, ni->ni_essid,
                  ni->ni_chan->ic_freq, ni->ni_chan->ic_flags);
          printf("\tfails %u inact %u txrate %u\n",
                  ni->ni_fails, ni->ni_inact, ni->ni_txrate);
  }
  
  void
  ieee80211_dump_nodes(struct ieee80211_node_table *nt)
  {
          ieee80211_iterate_nodes(nt,
                  (ieee80211_iter_func *) ieee80211_dump_node, nt);
  }
  
  /*
   * Handle a station joining an 11g network.
   */
  static void
  ieee80211_node_join_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
  {
  
          /*
           * Station isn't capable of short slot time.  Bump
           * the count of long slot time stations and disable
           * use of short slot time.  Note that the actual switch
           * over to long slot time use may not occur until the
           * next beacon transmission (per sec. 7.3.1.4 of 11g).
           */
          if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
                  ic->ic_longslotsta++;
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                      "[%s] station needs long slot time, count %d\n",
                      ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
                  /* XXX vap's w/ conflicting needs won't work */
                  ieee80211_set_shortslottime(ic, 0);
          }
          /*
           * If the new station is not an ERP station
           * then bump the counter and enable protection
           * if configured.
           */
          if (!ieee80211_iserp_rateset(ic, &ni->ni_rates)) {
                  ic->ic_nonerpsta++;
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                      "[%s] station is !ERP, %d non-ERP stations associated\n",
                      ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
                  /*
                   * If protection is configured, enable it.
                   */
                  if (ic->ic_protmode != IEEE80211_PROT_NONE) {
                          IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                              "%s: enable use of protection\n", __func__);
                          ic->ic_flags |= IEEE80211_F_USEPROT;
                  }
                  /*
                   * If station does not support short preamble
                   * then we must enable use of Barker preamble.
                   */
                  if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE) == 0) {
                          IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                              "[%s] station needs long preamble\n",
                              ether_sprintf(ni->ni_macaddr));
                          ic->ic_flags |= IEEE80211_F_USEBARKER;
                          ic->ic_flags &= ~IEEE80211_F_SHPREAMBLE;
                  }
          } else
                  ni->ni_flags |= IEEE80211_NODE_ERP;
  }
  
  void
  ieee80211_node_join(struct ieee80211com *ic, struct ieee80211_node *ni, int resp)
  {
          int newassoc;
  
          if (ni->ni_associd == 0) {
                  u_int16_t aid;
  
                  /*
                   * It would be good to search the bitmap
                   * more efficiently, but this will do for now.
                   */
                  for (aid = 1; aid < ic->ic_max_aid; aid++) {
                          if (!IEEE80211_AID_ISSET(aid,
                              ic->ic_aid_bitmap))
                                  break;
                  }
                  if (aid >= ic->ic_max_aid) {
                          IEEE80211_SEND_MGMT(ic, ni, resp,
                              IEEE80211_REASON_ASSOC_TOOMANY);
                          ieee80211_node_leave(ic, ni);
                          return;
                  }
                  ni->ni_associd = aid | 0xc000;
                  IEEE80211_AID_SET(ni->ni_associd, ic->ic_aid_bitmap);
                  ic->ic_sta_assoc++;
                  newassoc = 1;
                  if (ic->ic_curmode == IEEE80211_MODE_11G)
                          ieee80211_node_join_11g(ic, ni);
          } else
                  newassoc = 0;
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
              "[%s] station %sassociated at aid %d: %s preamble, %s slot time%s%s\n",
              ether_sprintf(ni->ni_macaddr), newassoc ? "" : "re",
              IEEE80211_NODE_AID(ni),
              ic->ic_flags & IEEE80211_F_SHPREAMBLE ? "short" : "long",
              ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long",
              ic->ic_flags & IEEE80211_F_USEPROT ? ", protection" : "",
              ni->ni_flags & IEEE80211_NODE_QOS ? ", QoS" : ""
          );
  
          /* give driver a chance to setup state like ni_txrate */
          if (ic->ic_newassoc != NULL)
                  ic->ic_newassoc(ni, newassoc);
          ni->ni_inact_reload = ic->ic_inact_auth;
          ni->ni_inact = ni->ni_inact_reload;
          IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS);
          /* tell the authenticator about new station */
          if (ic->ic_auth->ia_node_join != NULL)
                  ic->ic_auth->ia_node_join(ic, ni);
          ieee80211_notify_node_join(ic, ni, newassoc);
  }
  
  /*
   * Handle a station leaving an 11g network.
   */
  static void
  ieee80211_node_leave_11g(struct ieee80211com *ic, struct ieee80211_node *ni)
  {
  
          IASSERT(ic->ic_curmode == IEEE80211_MODE_11G,
               ("not in 11g, bss %u:0x%x, curmode %u", ni->ni_chan->ic_freq,
                ni->ni_chan->ic_flags, ic->ic_curmode));
  
          /*
           * If a long slot station do the slot time bookkeeping.
           */
          if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) == 0) {
                  IASSERT(ic->ic_longslotsta > 0,
                      ("bogus long slot station count %d", ic->ic_longslotsta));
                  ic->ic_longslotsta--;
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                      "[%s] long slot time station leaves, count now %d\n",
                      ether_sprintf(ni->ni_macaddr), ic->ic_longslotsta);
                  if (ic->ic_longslotsta == 0) {
                          /*
                           * Re-enable use of short slot time if supported
                           * and not operating in IBSS mode (per spec).
                           */
                          if ((ic->ic_caps & IEEE80211_C_SHSLOT) &&
                              ic->ic_opmode != IEEE80211_M_IBSS) {
                                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                                      "%s: re-enable use of short slot time\n",
                                      __func__);
                                  ieee80211_set_shortslottime(ic, 1);
                          }
                  }
          }
          /*
           * If a non-ERP station do the protection-related bookkeeping.
           */
          if ((ni->ni_flags & IEEE80211_NODE_ERP) == 0) {
                  IASSERT(ic->ic_nonerpsta > 0,
                      ("bogus non-ERP station count %d", ic->ic_nonerpsta));
                  ic->ic_nonerpsta--;
                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                      "[%s] non-ERP station leaves, count now %d\n",
                      ether_sprintf(ni->ni_macaddr), ic->ic_nonerpsta);
                  if (ic->ic_nonerpsta == 0) {
                          IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                                  "%s: disable use of protection\n", __func__);
                          ic->ic_flags &= ~IEEE80211_F_USEPROT;
                          /* XXX verify mode? */
                          if (ic->ic_caps & IEEE80211_C_SHPREAMBLE) {
                                  IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
                                      "%s: re-enable use of short preamble\n",
                                      __func__);
                                  ic->ic_flags |= IEEE80211_F_SHPREAMBLE;
                                  ic->ic_flags &= ~IEEE80211_F_USEBARKER;
                          }
                  }
          }
  }
  
  /*
   * Handle bookkeeping for station deauthentication/disassociation
   * when operating as an ap.
   */
  void
  ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni)
  {
          struct ieee80211_node_table *nt = ni->ni_table;
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC | IEEE80211_MSG_DEBUG,
              "[%s] station with aid %d leaves\n",
              ether_sprintf(ni->ni_macaddr), IEEE80211_NODE_AID(ni));
  
          IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
                  ic->ic_opmode == IEEE80211_M_IBSS ||
                  ic->ic_opmode == IEEE80211_M_AHDEMO,
                  ("unexpected operating mode %u", ic->ic_opmode));
          /*
           * If node wasn't previously associated all
           * we need to do is reclaim the reference.
           */
          /* XXX ibss mode bypasses 11g and notification */
          if (ni->ni_associd == 0)
                  goto done;
          /*
           * Tell the authenticator the station is leaving.
           * Note that we must do this before yanking the
           * association id as the authenticator uses the
           * associd to locate it's state block.
           */
          if (ic->ic_auth->ia_node_leave != NULL)
                  ic->ic_auth->ia_node_leave(ic, ni);
          IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap);
          ni->ni_associd = 0;
          ic->ic_sta_assoc--;
  
          if (ic->ic_curmode == IEEE80211_MODE_11G)
                  ieee80211_node_leave_11g(ic, ni);
          /*
           * Cleanup station state.  In particular clear various
           * state that might otherwise be reused if the node
           * is reused before the reference count goes to zero
           * (and memory is reclaimed).
           */
          ieee80211_sta_leave(ic, ni);
  done:
          /*
           * Remove the node from any table it's recorded in and
           * drop the caller's reference.  Removal from the table
           * is important to insure the node is not reprocessed
           * for inactivity.
           */
          if (nt != NULL) {
                  IEEE80211_NODE_LOCK(nt);
                  node_reclaim(nt, ni);
                  IEEE80211_NODE_UNLOCK(nt);
          } else
                  ieee80211_free_node(ni);
  }
  
  u_int8_t
  ieee80211_getrssi(struct ieee80211com *ic)
  {
  #define NZ(x)   ((x) == 0 ? 1 : (x))
          struct ieee80211_node_table *nt = &ic->ic_sta;
          u_int32_t rssi_samples, rssi_total;
          struct ieee80211_node *ni;
  
          rssi_total = 0;
          rssi_samples = 0;
          switch (ic->ic_opmode) {
          case IEEE80211_M_IBSS:          /* average of all ibss neighbors */
                  /* XXX locking */
                  TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
                          if (ni->ni_capinfo & IEEE80211_CAPINFO_IBSS) {
                                  rssi_samples++;
                                  rssi_total += ic->ic_node_getrssi(ni);
                          }
                  break;
          case IEEE80211_M_AHDEMO:        /* average of all neighbors */
                  /* XXX locking */
                  TAILQ_FOREACH(ni, &nt->nt_node, ni_list) {
                          rssi_samples++;
                          rssi_total += ic->ic_node_getrssi(ni);
                  }
                  break;
          case IEEE80211_M_HOSTAP:        /* average of all associated stations */
  #ifndef IEEE80211_NO_HOSTAP
                  /* XXX locking */
                  TAILQ_FOREACH(ni, &nt->nt_node, ni_list)
                          if (IEEE80211_AID(ni->ni_associd) != 0) {
                                  rssi_samples++;
                                  rssi_total += ic->ic_node_getrssi(ni);
                          }
  #endif /* !IEEE80211_NO_HOSTAP */
                  break;
          case IEEE80211_M_MONITOR:       /* XXX */
          case IEEE80211_M_STA:           /* use stats from associated ap */
          default:
                  if (ic->ic_bss != NULL)
                          rssi_total = ic->ic_node_getrssi(ic->ic_bss);
                  rssi_samples = 1;
                  break;
          }
          return rssi_total / NZ(rssi_samples);
  #undef NZ
  }
  
  /*
   * Indicate whether there are frames queued for a station in power-save mode.
   */
  static void
  ieee80211_set_tim(struct ieee80211_node *ni, int set)
  {
          struct ieee80211com *ic = ni->ni_ic;
          u_int16_t aid;
  
          IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP ||
                  ic->ic_opmode == IEEE80211_M_IBSS,
                  ("operating mode %u", ic->ic_opmode));
  
          aid = IEEE80211_AID(ni->ni_associd);
          IASSERT(aid < ic->ic_max_aid,
                  ("bogus aid %u, max %u", aid, ic->ic_max_aid));
  
          IEEE80211_BEACON_LOCK(ic);
          if (set != (isset(ic->ic_tim_bitmap, aid) != 0)) {
                  if (set) {
                          setbit(ic->ic_tim_bitmap, aid);
                          ic->ic_ps_pending++;
                  } else {
                          clrbit(ic->ic_tim_bitmap, aid);
                          ic->ic_ps_pending--;
                  }
                  ic->ic_flags |= IEEE80211_F_TIMUPDATE;
          }
          IEEE80211_BEACON_UNLOCK(ic);
  }
  
  /*
   * Node table support.
   */
  
  static void
  ieee80211_node_table_init(struct ieee80211com *ic,
          struct ieee80211_node_table *nt,
          const char *name, int inact, int keyixmax,
          void (*timeout)(struct ieee80211_node_table *))
  {
  
          IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
                  "%s %s table, inact %u\n", __func__, name, inact);
  
          nt->nt_ic = ic;
          /* XXX need unit */
          IEEE80211_NODE_LOCK_INIT(nt, ic->ic_ifp->if_xname);
          IEEE80211_SCAN_LOCK_INIT(nt, ic->ic_ifp->if_xname);
          TAILQ_INIT(&nt->nt_node);
          nt->nt_name = name;
          nt->nt_scangen = 1;
          nt->nt_inact_init = inact;
          nt->nt_timeout = timeout;
          nt->nt_keyixmax = keyixmax;
          if (nt->nt_keyixmax > 0) {
                  nt->nt_keyixmap = malloc(keyixmax *
                      sizeof(struct ieee80211_node *), M_80211_NODE,
                      M_NOWAIT | M_ZERO);
                  if (nt->nt_keyixmap == NULL)
                          if_printf(ic->ic_ifp,
                              "Cannot allocate key index map with %u entries\n",
                              keyixmax);
          } else
                  nt->nt_keyixmap = NULL;
  }
  
  void
  ieee80211_node_table_reset(struct ieee80211_node_table *nt)
  {
  
          IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
                  "%s %s table\n", __func__, nt->nt_name);
  
          IEEE80211_NODE_LOCK(nt);
          nt->nt_inact_timer = 0;
          ieee80211_free_allnodes_locked(nt);
          IEEE80211_NODE_UNLOCK(nt);
  }
  
  static void
  ieee80211_node_table_cleanup(struct ieee80211_node_table *nt)
  {
  
          IEEE80211_DPRINTF(nt->nt_ic, IEEE80211_MSG_NODE,
                  "%s %s table\n", __func__, nt->nt_name);
  
          IEEE80211_NODE_LOCK(nt);
          ieee80211_free_allnodes_locked(nt);
          IEEE80211_NODE_UNLOCK(nt);
          if (nt->nt_keyixmap != NULL) {
                  /* XXX verify all entries are NULL */
                  int i;
                  for (i = 0; i < nt->nt_keyixmax; i++)
                          if (nt->nt_keyixmap[i] != NULL)
                                  printf("%s: %s[%u] still active\n", __func__,
                                          nt->nt_name, i);
                  FREE(nt->nt_keyixmap, M_80211_NODE);
                  nt->nt_keyixmap = NULL;
          }
          IEEE80211_SCAN_LOCK_DESTROY(nt);
          IEEE80211_NODE_LOCK_DESTROY(nt);
  }

Cache object: 0b6264de774bb9f21ed8e577d2ccf423