/* $OpenBSD: ieee80211_node.c,v 1.5 2005/05/25 07:40:49 reyk Exp $ */ /* $NetBSD: ieee80211_node.c,v 1.14 2004/05/09 09:18:47 dyoung Exp $ */ /*- * Copyright (c) 2001 Atsushi Onoe * Copyright (c) 2002, 2003 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 #if defined(__FreeBSD__) __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_node.c,v 1.22 2004/04/05 04:15:55 sam Exp $"); #elif defined(__NetBSD__) __KERNEL_RCSID(0, "$NetBSD: ieee80211_node.c,v 1.14 2004/05/09 09:18:47 dyoung Exp $"); #endif #if defined(__NetBSD__) #include "opt_inet.h" #endif #include "bpfilter.h" #include #include #include #include #include #include #include #include #include #ifdef __FreeBSD__ #include #endif #include #include #ifdef __FreeBSD__ #include #endif #include #include #include #include #if defined(__FreeBSD__) #include #elif defined(__NetBSD__) #include #endif #include #if NBPFILTER > 0 #include #endif #ifdef INET #include #if defined(__FreeBSD__) || defined(__OpenBSD__) #include #else #include #endif #endif #include #include #ifdef __OpenBSD__ #include #endif static struct ieee80211_node *ieee80211_node_alloc(struct ieee80211com *); static void ieee80211_node_free(struct ieee80211com *, struct ieee80211_node *); static void ieee80211_node_copy(struct ieee80211com *, struct ieee80211_node *, const struct ieee80211_node *); static u_int8_t ieee80211_node_getrssi(struct ieee80211com *, struct ieee80211_node *); static void ieee80211_setup_node(struct ieee80211com *ic, struct ieee80211_node *ni, u_int8_t *macaddr); static void ieee80211_free_node(struct ieee80211com *, struct ieee80211_node *); static struct ieee80211_node *ieee80211_alloc_node_helper(struct ieee80211com *); static void ieee80211_node_cleanup(struct ieee80211com *, struct ieee80211_node *); #ifdef __NetBSD__ MALLOC_DEFINE(M_80211_NODE, "80211node", "802.11 node state"); #else #define M_80211_NODE M_DEVBUF #endif void ieee80211_node_attach(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; int size; IEEE80211_NODE_LOCK_INIT(ic, ifp->if_xname); TAILQ_INIT(&ic->ic_node); ic->ic_node_alloc = ieee80211_node_alloc; ic->ic_node_free = ieee80211_node_free; ic->ic_node_copy = ieee80211_node_copy; ic->ic_node_getrssi = ieee80211_node_getrssi; ic->ic_scangen = 1; ic->ic_max_nnodes = ieee80211_cache_size; if (ic->ic_max_aid == 0) ic->ic_max_aid = IEEE80211_AID_DEF; else if (ic->ic_max_aid > IEEE80211_AID_MAX) ic->ic_max_aid = IEEE80211_AID_MAX; size = howmany(ic->ic_max_aid, 32) * sizeof(u_int32_t); MALLOC(ic->ic_aid_bitmap, u_int32_t *, size, M_DEVBUF, M_NOWAIT); 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; } memset(ic->ic_aid_bitmap, 0, size); } static struct ieee80211_node * ieee80211_alloc_node_helper(struct ieee80211com *ic) { struct ieee80211_node *ni; if (ic->ic_nnodes >= ic->ic_max_nnodes) ieee80211_clean_nodes(ic); if (ic->ic_nnodes >= ic->ic_max_nnodes) return NULL; ni = (*ic->ic_node_alloc)(ic); if (ni != NULL) ic->ic_nnodes++; return ni; } void ieee80211_node_lateattach(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; struct ieee80211_node *ni; ni = ieee80211_alloc_node_helper(ic); IASSERT(ni != NULL, ("unable to setup inital BSS node")); ni->ni_chan = IEEE80211_CHAN_ANYC; ic->ic_bss = ieee80211_ref_node(ni); ic->ic_txpower = IEEE80211_TXPOWER_MAX; } void ieee80211_node_detach(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; if (ic->ic_bss != NULL) { (*ic->ic_node_free)(ic, ic->ic_bss); ic->ic_bss = NULL; } ieee80211_free_allnodes(ic); IEEE80211_NODE_LOCK_DESTROY(ic); if (ic->ic_aid_bitmap != NULL) FREE(ic->ic_aid_bitmap, M_DEVBUF); } /* * AP scanning support. */ /* * Initialize the active channel set based on the set * of available channels and the current PHY mode. */ static void ieee80211_reset_scan(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; memcpy(ic->ic_chan_scan, ic->ic_chan_active, sizeof(ic->ic_chan_active)); /* NB: hack, setup so next_scan starts with the first channel */ if (ic->ic_bss->ni_chan == IEEE80211_CHAN_ANYC) ic->ic_bss->ni_chan = &ic->ic_channels[IEEE80211_CHAN_MAX]; } /* * Begin an active scan. */ void ieee80211_begin_scan(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; if (ic->ic_scan_lock & IEEE80211_SCAN_LOCKED) return; ic->ic_scan_lock |= IEEE80211_SCAN_LOCKED; /* * 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++; if (ifp->if_flags & IFF_DEBUG) if_printf(ifp, "begin %s scan\n", (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive"); /* * Clear scan state and flush any previously seen * AP's. Note that the latter assumes we don't act * as both an AP and a station, otherwise we'll * potentially flush state of stations associated * with us. */ ieee80211_reset_scan(ifp); ieee80211_free_allnodes(ic); /* Reset the current mode. */ if (IFM_MODE(ic->ic_media.ifm_cur->ifm_media) == IFM_AUTO) { ic->ic_curmode = IEEE80211_MODE_AUTO; ieee80211_setmode(ic, ic->ic_curmode); } ic->ic_scan_count = 0; /* Scan the next channel. */ ieee80211_next_scan(ifp); } /* * Switch to the next channel marked for scanning. */ void ieee80211_next_scan(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; struct ieee80211_channel *chan; chan = ic->ic_bss->ni_chan; for (;;) { if (++chan > &ic->ic_channels[IEEE80211_CHAN_MAX]) chan = &ic->ic_channels[0]; if (isset(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan))) { /* * Honor channels marked passive-only * during an active scan. */ if ((ic->ic_flags & IEEE80211_F_ASCAN) == 0 || (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0) break; } if (chan == ic->ic_bss->ni_chan) { ieee80211_end_scan(ifp); return; } } clrbit(ic->ic_chan_scan, ieee80211_chan2ieee(ic, chan)); IEEE80211_DPRINTF(("%s: chan %d->%d\n", __func__, ieee80211_chan2ieee(ic, ic->ic_bss->ni_chan), ieee80211_chan2ieee(ic, chan))); ic->ic_bss->ni_chan = chan; ieee80211_new_state(ic, IEEE80211_S_SCAN, -1); } void ieee80211_create_ibss(struct ieee80211com* ic, struct ieee80211_channel *chan) { struct ieee80211_node *ni; struct ifnet *ifp = &ic->ic_if; ni = ic->ic_bss; if (ifp->if_flags & IFF_DEBUG) if_printf(ifp, "creating ibss\n"); ic->ic_flags |= IEEE80211_F_SIBSS; ni->ni_chan = chan; ni->ni_rates = ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)]; IEEE80211_ADDR_COPY(ni->ni_macaddr, ic->ic_myaddr); IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_myaddr); if (ic->ic_opmode == IEEE80211_M_IBSS) { if ((ic->ic_flags & IEEE80211_F_DESBSSID) != 0) IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_des_bssid); else ni->ni_bssid[0] |= 0x02; /* local bit for IBSS */ } ni->ni_esslen = ic->ic_des_esslen; memcpy(ni->ni_essid, ic->ic_des_essid, ni->ni_esslen); ni->ni_rssi = 0; ni->ni_rstamp = 0; memset(ni->ni_tstamp, 0, sizeof(ni->ni_tstamp)); ni->ni_intval = ic->ic_lintval; ni->ni_capinfo = IEEE80211_CAPINFO_IBSS; if (ic->ic_flags & IEEE80211_F_WEPON) ni->ni_capinfo |= IEEE80211_CAPINFO_PRIVACY; if (ic->ic_phytype == IEEE80211_T_FH) { ni->ni_fhdwell = 200; /* XXX */ ni->ni_fhindex = 1; } ieee80211_new_state(ic, IEEE80211_S_RUN, -1); } 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_WEPON) { 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(ic, ni, IEEE80211_F_DONEGO); 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; #ifdef IEEE80211_DEBUG if (ic->ic_if.if_flags & IFF_DEBUG) { printf(" %c %s", 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; } /* * Complete a scan of potential channels. */ void ieee80211_end_scan(struct ifnet *ifp) { struct ieee80211com *ic = (void *)ifp; struct ieee80211_node *ni, *nextbs, *selbs; int i, fail; if (ifp->if_flags & IFF_DEBUG) if_printf(ifp, "end %s scan\n", (ic->ic_flags & IEEE80211_F_ASCAN) ? "active" : "passive"); if (ic->ic_scan_count) ic->ic_flags &= ~IEEE80211_F_ASCAN; ni = TAILQ_FIRST(&ic->ic_node); if (ic->ic_opmode == IEEE80211_M_HOSTAP) { /* XXX off stack? */ u_char occupied[roundup(IEEE80211_CHAN_MAX, NBBY)]; /* * 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 unnoccupied one. If that fails, pick a random * channel from the active set. */ for (; ni != NULL; ni = nextbs) { nextbs = TAILQ_NEXT(ni, ni_list); setbit(occupied, ieee80211_chan2ieee(ic, ni->ni_chan)); } for (i = 0; i < IEEE80211_CHAN_MAX; i++) if (isset(ic->ic_chan_active, i) && isclr(occupied, i)) break; if (i == IEEE80211_CHAN_MAX) { fail = arc4random() & 3; /* random 0-3 */ for (i = 0; i < IEEE80211_CHAN_MAX; i++) if (isset(ic->ic_chan_active, i) && fail-- == 0) break; } ieee80211_create_ibss(ic, &ic->ic_channels[i]); goto wakeup; } if (ni == NULL) { IEEE80211_DPRINTF(("%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); goto wakeup; } /* * Scan the next mode if nothing has been found. This * is necessary if the device supports different * incompatible modes in the same channel range, like * like 11b and "pure" 11G mode. This will loop * forever except for user-initiated scans. */ if (ieee80211_next_mode(ifp) == IEEE80211_MODE_AUTO) { if (ic->ic_scan_lock & IEEE80211_SCAN_REQUEST && ic->ic_scan_lock & IEEE80211_SCAN_RESUME) { ic->ic_scan_lock = IEEE80211_SCAN_LOCKED; /* Return from an user-initiated scan */ wakeup(&ic->ic_scan_lock); } else if (ic->ic_scan_lock & IEEE80211_SCAN_REQUEST) goto wakeup; ic->ic_scan_count++; } /* * Reset the list of channels to scan and start again. */ ieee80211_reset_scan(ifp); ieee80211_next_scan(ifp); return; } selbs = NULL; for (; ni != NULL; ni = nextbs) { nextbs = TAILQ_NEXT(ni, ni_list); if (ni->ni_fails) { /* * The configuration of the access points may change * during my scan. So delete the entry for the AP * and retry to associate if there is another beacon. */ if (ni->ni_fails++ > 2) ieee80211_free_node(ic, ni); continue; } if (ieee80211_match_bss(ic, ni) == 0) { if (selbs == NULL) selbs = ni; else if (ni->ni_rssi > selbs->ni_rssi) selbs = ni; } } if (selbs == NULL) goto notfound; (*ic->ic_node_copy)(ic, ic->ic_bss, selbs); ieee80211_node_newstate(selbs, IEEE80211_STA_BSS); if (ic->ic_opmode == IEEE80211_M_IBSS) { ieee80211_fix_rate(ic, ic->ic_bss, IEEE80211_F_DOFRATE | IEEE80211_F_DONEGO | IEEE80211_F_DODEL); if (ic->ic_bss->ni_rates.rs_nrates == 0) goto notfound; ieee80211_new_state(ic, IEEE80211_S_RUN, -1); } else { ieee80211_new_state(ic, IEEE80211_S_AUTH, -1); } wakeup: if (ic->ic_scan_lock & IEEE80211_SCAN_REQUEST) { /* Return from an user-initiated scan */ wakeup(&ic->ic_scan_lock); } ic->ic_scan_lock = IEEE80211_SCAN_UNLOCKED; } int ieee80211_get_rate(struct ieee80211com *ic) { u_int8_t (*rates)[IEEE80211_RATE_MAXSIZE]; int rate; rates = &ic->ic_bss->ni_rates.rs_rates; if (ic->ic_fixed_rate != -1) rate = (*rates)[ic->ic_fixed_rate]; else if (ic->ic_state == IEEE80211_S_RUN) rate = (*rates)[ic->ic_bss->ni_txrate]; else rate = 0; return rate & IEEE80211_RATE_VAL; } static struct ieee80211_node * ieee80211_node_alloc(struct ieee80211com *ic) { struct ieee80211_node *ni; MALLOC(ni, struct ieee80211_node *, sizeof(struct ieee80211_node), M_80211_NODE, M_NOWAIT); if (ni != NULL) memset(ni, 0, sizeof(struct ieee80211_node)); return ni; } static void ieee80211_node_cleanup(struct ieee80211com *ic, struct ieee80211_node *ni) { if (ni->ni_challenge != NULL) { FREE(ni->ni_challenge, M_DEVBUF); ni->ni_challenge = NULL; } } static void ieee80211_node_free(struct ieee80211com *ic, struct ieee80211_node *ni) { ieee80211_node_cleanup(ic, ni); FREE(ni, M_80211_NODE); } static void ieee80211_node_copy(struct ieee80211com *ic, struct ieee80211_node *dst, const struct ieee80211_node *src) { ieee80211_node_cleanup(ic, dst); *dst = *src; dst->ni_challenge = NULL; } static u_int8_t ieee80211_node_getrssi(struct ieee80211com *ic, struct ieee80211_node *ni) { return ni->ni_rssi; } static void ieee80211_setup_node(struct ieee80211com *ic, struct ieee80211_node *ni, u_int8_t *macaddr) { int hash; IEEE80211_DPRINTF(("%s %s\n", __func__, ether_sprintf(macaddr))); IEEE80211_ADDR_COPY(ni->ni_macaddr, macaddr); hash = IEEE80211_NODE_HASH(macaddr); ieee80211_node_newstate(ni, IEEE80211_STA_CACHE); IEEE80211_NODE_LOCK_BH(ic); /* * Note we don't enable the inactive timer when acting * as a station. Nodes created in this mode represent * AP's identified while scanning. If we time them out * then several things happen: we can't return the data * to users to show the list of AP's we encountered, and * more importantly, we'll incorrectly deauthenticate * ourself because the inactivity timer will kick us off. */ if (ic->ic_opmode != IEEE80211_M_STA && TAILQ_EMPTY(&ic->ic_node)) ic->ic_inact_timer = IEEE80211_INACT_WAIT; TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); LIST_INSERT_HEAD(&ic->ic_hash[hash], ni, ni_hash); IEEE80211_NODE_UNLOCK_BH(ic); } struct ieee80211_node * ieee80211_alloc_node(struct ieee80211com *ic, u_int8_t *macaddr) { struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic); if (ni != NULL) ieee80211_setup_node(ic, ni, macaddr); else ic->ic_stats.is_rx_nodealloc++; return ni; } struct ieee80211_node * ieee80211_dup_bss(struct ieee80211com *ic, u_int8_t *macaddr) { struct ieee80211_node *ni = ieee80211_alloc_node_helper(ic); if (ni != NULL) { ieee80211_setup_node(ic, ni, macaddr); /* * Inherit from ic_bss. */ IEEE80211_ADDR_COPY(ni->ni_bssid, ic->ic_bss->ni_bssid); ni->ni_chan = ic->ic_bss->ni_chan; } else ic->ic_stats.is_rx_nodealloc++; return ni; } static struct ieee80211_node * _ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) { struct ieee80211_node *ni; int hash; IEEE80211_NODE_LOCK_ASSERT(ic); hash = IEEE80211_NODE_HASH(macaddr); LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { if (IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) { /* least-recently used is at tail */ TAILQ_REMOVE(&ic->ic_node, ni, ni_list); TAILQ_INSERT_TAIL(&ic->ic_node, ni, ni_list); return ni; } } return NULL; } struct ieee80211_node * ieee80211_find_node(struct ieee80211com *ic, u_int8_t *macaddr) { struct ieee80211_node *ni; IEEE80211_NODE_LOCK(ic); ni = _ieee80211_find_node(ic, macaddr); IEEE80211_NODE_UNLOCK(ic); return ni; } /* * Return a reference to the appropriate node for sending * a data frame. This handles node discovery in adhoc networks. * * Drivers will call this, so increase the reference count before * returning the node. */ struct ieee80211_node * ieee80211_find_txnode(struct ieee80211com *ic, u_int8_t *macaddr) { struct ieee80211_node *ni; /* * The destination address should be in the node table * unless we are operating in station mode or this is a * multicast/broadcast frame. */ if (ic->ic_opmode == IEEE80211_M_STA || IEEE80211_IS_MULTICAST(macaddr)) return ieee80211_ref_node(ic->ic_bss); /* XXX can't hold lock across dup_bss 'cuz of recursive locking */ IEEE80211_NODE_LOCK(ic); ni = _ieee80211_find_node(ic, macaddr); IEEE80211_NODE_UNLOCK(ic); if (ni == NULL) { if (ic->ic_opmode != IEEE80211_M_IBSS && ic->ic_opmode != IEEE80211_M_AHDEMO) return NULL; /* * 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. * * XXX need better way to handle this; issue probe * request so we can deduce rate set, etc. */ if ((ni = ieee80211_dup_bss(ic, macaddr)) == NULL) return NULL; /* XXX no rate negotiation; just dup */ ni->ni_rates = ic->ic_bss->ni_rates; if (ic->ic_newassoc) (*ic->ic_newassoc)(ic, ni, 1); } return ieee80211_ref_node(ni); } /* * It is usually desirable to process a Rx packet using its sender's * node-record instead of the BSS record. * * - AP mode: keep a node-record for every authenticated/associated * station *in the BSS*. For future use, we also track neighboring * APs, since they might belong to the same ESS. APs in the same * ESS may bridge packets to each other, forming a Wireless * Distribution System (WDS). * * - IBSS mode: keep a node-record for every station *in the BSS*. * Also track neighboring stations by their beacons/probe responses. * * - monitor mode: keep a node-record for every sender, regardless * of BSS. * * - STA mode: the only available node-record is the BSS record, * ic->ic_bss. * * Of all the 802.11 Control packets, only the node-records for * RTS packets node-record can be looked up. * * Return non-zero if the packet's node-record is kept, zero * otherwise. */ static __inline int ieee80211_needs_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh, u_int8_t **bssid) { struct ieee80211_node *bss = ic->ic_bss; int monitor, rc = 0; monitor = (ic->ic_opmode == IEEE80211_M_MONITOR); *bssid = NULL; switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) { case IEEE80211_FC0_TYPE_CTL: if (!monitor) break; return (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_RTS; case IEEE80211_FC0_TYPE_MGT: *bssid = wh->i_addr3; switch (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) { case IEEE80211_FC0_SUBTYPE_BEACON: case IEEE80211_FC0_SUBTYPE_PROBE_RESP: rc = 1; break; default: if (ic->ic_opmode == IEEE80211_M_STA) break; rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid) || IEEE80211_ADDR_EQ(*bssid, etherbroadcastaddr); break; } break; case IEEE80211_FC0_TYPE_DATA: switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) { case IEEE80211_FC1_DIR_NODS: *bssid = wh->i_addr3; if (ic->ic_opmode == IEEE80211_M_IBSS || ic->ic_opmode == IEEE80211_M_AHDEMO) rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); break; case IEEE80211_FC1_DIR_TODS: *bssid = wh->i_addr1; if (ic->ic_opmode == IEEE80211_M_HOSTAP) rc = IEEE80211_ADDR_EQ(*bssid, bss->ni_bssid); break; case IEEE80211_FC1_DIR_FROMDS: case IEEE80211_FC1_DIR_DSTODS: *bssid = wh->i_addr2; rc = (ic->ic_opmode == IEEE80211_M_HOSTAP); break; } break; } return monitor || rc; } /* * Drivers call this, so increase the reference count before returning * the node. */ struct ieee80211_node * ieee80211_find_rxnode(struct ieee80211com *ic, struct ieee80211_frame *wh) { struct ieee80211_node *ni; const static u_int8_t zero[IEEE80211_ADDR_LEN]; u_int8_t *bssid; if (!ieee80211_needs_rxnode(ic, wh, &bssid)) return ieee80211_ref_node(ic->ic_bss); IEEE80211_NODE_LOCK(ic); ni = _ieee80211_find_node(ic, wh->i_addr2); IEEE80211_NODE_UNLOCK(ic); if (ni != NULL) return ieee80211_ref_node(ni); if (ic->ic_opmode == IEEE80211_M_HOSTAP) return ieee80211_ref_node(ic->ic_bss); /* XXX see remarks in ieee80211_find_txnode */ /* XXX no rate negotiation; just dup */ if ((ni = ieee80211_dup_bss(ic, wh->i_addr2)) == NULL) return ieee80211_ref_node(ic->ic_bss); IEEE80211_ADDR_COPY(ni->ni_bssid, (bssid != NULL) ? bssid : zero); ni->ni_rates = ic->ic_bss->ni_rates; if (ic->ic_newassoc) (*ic->ic_newassoc)(ic, ni, 1); IEEE80211_DPRINTF(("%s: faked-up node %p for %s\n", __func__, ni, ether_sprintf(wh->i_addr2))); return ieee80211_ref_node(ni); } /* * Like find but search based on the channel too. * * Note that ieee80211_find_node_for_beacon does not increase the * reference count before returning the node, because drivers are not * expected to call it. */ struct ieee80211_node * ieee80211_find_node_for_beacon(struct ieee80211com *ic, u_int8_t *macaddr, struct ieee80211_channel *chan, char *ssid) { struct ieee80211_node *ni, *best; int hash, best_score, score; best = NULL; best_score = -1; hash = IEEE80211_NODE_HASH(macaddr); IEEE80211_NODE_LOCK(ic); LIST_FOREACH(ni, &ic->ic_hash[hash], ni_hash) { if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, macaddr)) continue; score = (ni->ni_chan == chan) ? 1 : 0; if (ssid[1] == 0 || ni->ni_esslen == 0) score++; else if (ssid[1] != ni->ni_esslen || memcmp(ssid + 2, ni->ni_essid, ssid[1]) != 0) continue; if (score > best_score) { best = ni; best_score = score; } } IEEE80211_NODE_UNLOCK(ic); return best; } struct ieee80211_node * ieee80211_lookup_node(struct ieee80211com *ic, u_int8_t *macaddr, struct ieee80211_channel *chan) { char ssid[2] = { 0, 0 }; return ieee80211_find_node_for_beacon(ic, macaddr, chan, ssid); } static void ieee80211_free_node(struct ieee80211com *ic, struct ieee80211_node *ni) { IASSERT(ni != ic->ic_bss, ("freeing bss node")); IEEE80211_DPRINTF(("%s %s\n", __func__, ether_sprintf(ni->ni_macaddr))); IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); TAILQ_REMOVE(&ic->ic_node, ni, ni_list); LIST_REMOVE(ni, ni_hash); ic->ic_nnodes--; if (!IF_IS_EMPTY(&ni->ni_savedq)) { IF_PURGE(&ni->ni_savedq); if (ic->ic_set_tim) (*ic->ic_set_tim)(ic, ni->ni_associd, 0); } if (TAILQ_EMPTY(&ic->ic_node)) ic->ic_inact_timer = 0; (*ic->ic_node_free)(ic, ni); /* TBD indicate to drivers that a new node can be allocated */ } void ieee80211_release_node(struct ieee80211com *ic, struct ieee80211_node *ni) { IEEE80211_DPRINTF(("%s %s refcnt %d\n", __func__, ether_sprintf(ni->ni_macaddr), ni->ni_refcnt)); if (ieee80211_node_decref(ni) == 0 && ni->ni_state == IEEE80211_STA_COLLECT) { IEEE80211_NODE_LOCK_BH(ic); ieee80211_free_node(ic, ni); IEEE80211_NODE_UNLOCK_BH(ic); } } void ieee80211_free_allnodes(struct ieee80211com *ic) { struct ieee80211_node *ni; IEEE80211_DPRINTF(("%s\n", __func__)); IEEE80211_NODE_LOCK_BH(ic); while ((ni = TAILQ_FIRST(&ic->ic_node)) != NULL) ieee80211_free_node(ic, ni); IEEE80211_NODE_UNLOCK_BH(ic); if (ic->ic_bss != NULL) ieee80211_node_cleanup(ic, ic->ic_bss); /* for station mode */ } /* * Timeout inactive nodes. 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. */ void ieee80211_clean_nodes(struct ieee80211com *ic) { struct ieee80211_node *ni, *next_ni; u_int gen = ic->ic_scangen++; /* NB: ok 'cuz single-threaded*/ IEEE80211_NODE_LOCK(ic); for (ni = TAILQ_FIRST(&ic->ic_node); ni != NULL; ni = next_ni) { next_ni = TAILQ_NEXT(ni, ni_list); if (ic->ic_nnodes <= ic->ic_max_nnodes) break; if (ni->ni_scangen == gen) /* previously handled */ continue; ni->ni_scangen = gen; if (ni->ni_refcnt > 0) continue; IEEE80211_DPRINTF(("station %s purged from LRU cache\n", ether_sprintf(ni->ni_macaddr))); /* * Send a deauthenticate frame. */ if (ic->ic_opmode == IEEE80211_M_HOSTAP) { IEEE80211_NODE_UNLOCK(ic); IEEE80211_SEND_MGMT(ic, ni, IEEE80211_FC0_SUBTYPE_DEAUTH, IEEE80211_REASON_AUTH_EXPIRE); IEEE80211_NODE_LOCK(ic); ieee80211_node_leave(ic, ni); } else ieee80211_free_node(ic, ni); ic->ic_stats.is_node_timeout++; } IEEE80211_NODE_UNLOCK(ic); } void ieee80211_iterate_nodes(struct ieee80211com *ic, ieee80211_iter_func *f, void *arg) { struct ieee80211_node *ni; IEEE80211_NODE_LOCK(ic); TAILQ_FOREACH(ni, &ic->ic_node, ni_list) (*f)(arg, ni); IEEE80211_NODE_UNLOCK(ic); } 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 clever 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); newassoc = 1; /* XXX for 11g must turn off short slot time if long slot time sta associates */ } else newassoc = 0; IEEE80211_DPRINTF(("station %s %s associated at aid %d\n", ether_sprintf(ni->ni_macaddr), (newassoc ? "newly" : "already"), ni->ni_associd & ~0xc000)); /* give driver a chance to setup state like ni_txrate */ if (ic->ic_newassoc) (*ic->ic_newassoc)(ic, ni, newassoc); IEEE80211_SEND_MGMT(ic, ni, resp, IEEE80211_STATUS_SUCCESS); ieee80211_node_newstate(ni, IEEE80211_STA_ASSOC); } /* * Handle bookkeeping for station deauthentication/disassociation * when operating as an ap. */ void ieee80211_node_leave(struct ieee80211com *ic, struct ieee80211_node *ni) { IASSERT(ic->ic_opmode == IEEE80211_M_HOSTAP, ("not in ap mode, mode %u", ic->ic_opmode)); /* * If node wasn't previously associated all * we need to do is reclaim the reference. */ if (ni->ni_associd == 0) return; IEEE80211_AID_CLR(ni->ni_associd, ic->ic_aid_bitmap); ni->ni_associd = 0; ieee80211_node_newstate(ni, IEEE80211_STA_COLLECT); }