xref: /freebsd/sys/net80211/ieee80211_wds.c (revision 49b49cda41feabe3439f7318e8bf40e3896c7bf4)
1 /*-
2  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #ifdef __FreeBSD__
28 __FBSDID("$FreeBSD$");
29 #endif
30 
31 /*
32  * IEEE 802.11 WDS mode support.
33  */
34 #include "opt_inet.h"
35 #include "opt_wlan.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/mbuf.h>
40 #include <sys/malloc.h>
41 #include <sys/kernel.h>
42 
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/endian.h>
46 #include <sys/errno.h>
47 #include <sys/proc.h>
48 #include <sys/sysctl.h>
49 
50 #include <net/if.h>
51 #include <net/if_var.h>
52 #include <net/if_media.h>
53 #include <net/if_llc.h>
54 #include <net/ethernet.h>
55 
56 #include <net/bpf.h>
57 
58 #include <net80211/ieee80211_var.h>
59 #include <net80211/ieee80211_wds.h>
60 #include <net80211/ieee80211_input.h>
61 #ifdef IEEE80211_SUPPORT_SUPERG
62 #include <net80211/ieee80211_superg.h>
63 #endif
64 
65 static void wds_vattach(struct ieee80211vap *);
66 static int wds_newstate(struct ieee80211vap *, enum ieee80211_state, int);
67 static	int wds_input(struct ieee80211_node *ni, struct mbuf *m,
68 	    const struct ieee80211_rx_stats *rxs, int, int);
69 static void wds_recv_mgmt(struct ieee80211_node *, struct mbuf *, int subtype,
70 	const struct ieee80211_rx_stats *, int, int);
71 
72 void
73 ieee80211_wds_attach(struct ieee80211com *ic)
74 {
75 	ic->ic_vattach[IEEE80211_M_WDS] = wds_vattach;
76 }
77 
78 void
79 ieee80211_wds_detach(struct ieee80211com *ic)
80 {
81 }
82 
83 static void
84 wds_vdetach(struct ieee80211vap *vap)
85 {
86 	if (vap->iv_bss != NULL) {
87 		/* XXX locking? */
88 		if (vap->iv_bss->ni_wdsvap == vap)
89 			vap->iv_bss->ni_wdsvap = NULL;
90 	}
91 }
92 
93 static void
94 wds_vattach(struct ieee80211vap *vap)
95 {
96 	vap->iv_newstate = wds_newstate;
97 	vap->iv_input = wds_input;
98 	vap->iv_recv_mgmt = wds_recv_mgmt;
99 	vap->iv_opdetach = wds_vdetach;
100 }
101 
102 static void
103 wds_flush(struct ieee80211_node *ni)
104 {
105 	struct ieee80211com *ic = ni->ni_ic;
106 	struct mbuf *m, *next;
107 	int8_t rssi, nf;
108 
109 	m = ieee80211_ageq_remove(&ic->ic_stageq,
110 	    (void *)(uintptr_t) ieee80211_mac_hash(ic, ni->ni_macaddr));
111 	if (m == NULL)
112 		return;
113 
114 	IEEE80211_NOTE(ni->ni_vap, IEEE80211_MSG_WDS, ni,
115 	    "%s", "flush wds queue");
116 	ic->ic_node_getsignal(ni, &rssi, &nf);
117 	for (; m != NULL; m = next) {
118 		next = m->m_nextpkt;
119 		m->m_nextpkt = NULL;
120 		ieee80211_input(ni, m, rssi, nf);
121 	}
122 }
123 
124 static int
125 ieee80211_create_wds(struct ieee80211vap *vap, struct ieee80211_channel *chan)
126 {
127 	struct ieee80211com *ic = vap->iv_ic;
128 	struct ieee80211_node_table *nt = &ic->ic_sta;
129 	struct ieee80211_node *ni, *obss;
130 
131 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
132 	     "%s: creating link to %s on channel %u\n", __func__,
133 	     ether_sprintf(vap->iv_des_bssid), ieee80211_chan2ieee(ic, chan));
134 
135 	/* NB: vap create must specify the bssid for the link */
136 	KASSERT(vap->iv_flags & IEEE80211_F_DESBSSID, ("no bssid"));
137 	/* NB: we should only be called on RUN transition */
138 	KASSERT(vap->iv_state == IEEE80211_S_RUN, ("!RUN state"));
139 
140 	if ((vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0) {
141 		/*
142 		 * Dynamic/non-legacy WDS.  Reference the associated
143 		 * station specified by the desired bssid setup at vap
144 		 * create.  Point ni_wdsvap at the WDS vap so 4-address
145 		 * frames received through the associated AP vap will
146 		 * be dispatched upward (e.g. to a bridge) as though
147 		 * they arrived on the WDS vap.
148 		 */
149 		IEEE80211_NODE_LOCK(nt);
150 		obss = NULL;
151 		ni = ieee80211_find_node_locked(&ic->ic_sta, vap->iv_des_bssid);
152 		if (ni == NULL) {
153 			/*
154 			 * Node went away before we could hookup.  This
155 			 * should be ok; no traffic will flow and a leave
156 			 * event will be dispatched that should cause
157 			 * the vap to be destroyed.
158 			 */
159 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
160 			    "%s: station %s went away\n",
161 			    __func__, ether_sprintf(vap->iv_des_bssid));
162 			/* XXX stat? */
163 		} else if (ni->ni_wdsvap != NULL) {
164 			/*
165 			 * Node already setup with a WDS vap; we cannot
166 			 * allow multiple references so disallow.  If
167 			 * ni_wdsvap points at us that's ok; we should
168 			 * do nothing anyway.
169 			 */
170 			/* XXX printf instead? */
171 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_WDS,
172 			    "%s: station %s in use with %s\n",
173 			    __func__, ether_sprintf(vap->iv_des_bssid),
174 			    ni->ni_wdsvap->iv_ifp->if_xname);
175 			/* XXX stat? */
176 		} else {
177 			/*
178 			 * Committed to new node, setup state.
179 			 */
180 			obss = vap->iv_bss;
181 			vap->iv_bss = ni;
182 			ni->ni_wdsvap = vap;
183 		}
184 		IEEE80211_NODE_UNLOCK(nt);
185 		if (obss != NULL) {
186 			/* NB: deferred to avoid recursive lock */
187 			ieee80211_free_node(obss);
188 		}
189 	} else {
190 		/*
191 		 * Legacy WDS vap setup.
192 		 */
193 		/*
194 		 * The far end does not associate so we just create
195 		 * create a new node and install it as the vap's
196 		 * bss node.  We must simulate an association and
197 		 * authorize the port for traffic to flow.
198 		 * XXX check if node already in sta table?
199 		 */
200 		ni = ieee80211_node_create_wds(vap, vap->iv_des_bssid, chan);
201 		if (ni != NULL) {
202 			obss = vap->iv_bss;
203 			vap->iv_bss = ieee80211_ref_node(ni);
204 			ni->ni_flags |= IEEE80211_NODE_AREF;
205 			if (obss != NULL)
206 				ieee80211_free_node(obss);
207 			/* give driver a chance to setup state like ni_txrate */
208 			if (ic->ic_newassoc != NULL)
209 				ic->ic_newassoc(ni, 1);
210 			/* tell the authenticator about new station */
211 			if (vap->iv_auth->ia_node_join != NULL)
212 				vap->iv_auth->ia_node_join(ni);
213 			if (ni->ni_authmode != IEEE80211_AUTH_8021X)
214 				ieee80211_node_authorize(ni);
215 
216 			ieee80211_notify_node_join(ni, 1 /*newassoc*/);
217 			/* XXX inject l2uf frame */
218 		}
219 	}
220 
221 	/*
222 	 * Flush any pending frames now that were setup.
223 	 */
224 	if (ni != NULL)
225 		wds_flush(ni);
226 	return (ni == NULL ? ENOENT : 0);
227 }
228 
229 /*
230  * Propagate multicast frames of an ap vap to all DWDS links.
231  * The caller is assumed to have verified this frame is multicast.
232  */
233 void
234 ieee80211_dwds_mcast(struct ieee80211vap *vap0, struct mbuf *m)
235 {
236 	struct ieee80211com *ic = vap0->iv_ic;
237 	const struct ether_header *eh = mtod(m, const struct ether_header *);
238 	struct ieee80211_node *ni;
239 	struct ieee80211vap *vap;
240 	struct ifnet *ifp;
241 	struct mbuf *mcopy;
242 	int err;
243 
244 	KASSERT(ETHER_IS_MULTICAST(eh->ether_dhost),
245 	    ("%s not mcast", ether_sprintf(eh->ether_dhost)));
246 
247 	/* XXX locking */
248 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
249 		/* only DWDS vaps are interesting */
250 		if (vap->iv_opmode != IEEE80211_M_WDS ||
251 		    (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY))
252 			continue;
253 		/* if it came in this interface, don't send it back out */
254 		ifp = vap->iv_ifp;
255 		if (ifp == m->m_pkthdr.rcvif)
256 			continue;
257 		/*
258 		 * Duplicate the frame and send it.
259 		 */
260 		mcopy = m_copypacket(m, M_NOWAIT);
261 		if (mcopy == NULL) {
262 			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
263 			/* XXX stat + msg */
264 			continue;
265 		}
266 		ni = ieee80211_find_txnode(vap, eh->ether_dhost);
267 		if (ni == NULL) {
268 			/* NB: ieee80211_find_txnode does stat+msg */
269 			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
270 			m_freem(mcopy);
271 			continue;
272 		}
273 		/* calculate priority so drivers can find the tx queue */
274 		if (ieee80211_classify(ni, mcopy)) {
275 			IEEE80211_DISCARD_MAC(vap,
276 			    IEEE80211_MSG_OUTPUT | IEEE80211_MSG_WDS,
277 			    eh->ether_dhost, NULL,
278 			    "%s", "classification failure");
279 			vap->iv_stats.is_tx_classify++;
280 			if_inc_counter(ifp, IFCOUNTER_OERRORS, 1);
281 			m_freem(mcopy);
282 			ieee80211_free_node(ni);
283 			continue;
284 		}
285 
286 		BPF_MTAP(ifp, m);		/* 802.3 tx */
287 
288 		/*
289 		 * Encapsulate the packet in prep for transmission.
290 		 */
291 		mcopy = ieee80211_encap(vap, ni, mcopy);
292 		if (mcopy == NULL) {
293 			/* NB: stat+msg handled in ieee80211_encap */
294 			ieee80211_free_node(ni);
295 			continue;
296 		}
297 		mcopy->m_flags |= M_MCAST;
298 		mcopy->m_pkthdr.rcvif = (void *) ni;
299 
300 		err = ieee80211_parent_xmitpkt(ic, mcopy);
301 		if (!err) {
302 			if_inc_counter(ifp, IFCOUNTER_OPACKETS, 1);
303 			if_inc_counter(ifp, IFCOUNTER_OMCASTS, 1);
304 			if_inc_counter(ifp, IFCOUNTER_OBYTES,
305 			    m->m_pkthdr.len);
306 		}
307 	}
308 }
309 
310 /*
311  * Handle DWDS discovery on receipt of a 4-address frame in
312  * ap mode.  Queue the frame and post an event for someone
313  * to plumb the necessary WDS vap for this station.  Frames
314  * received prior to the vap set running will then be reprocessed
315  * as if they were just received.
316  */
317 void
318 ieee80211_dwds_discover(struct ieee80211_node *ni, struct mbuf *m)
319 {
320 	struct ieee80211com *ic = ni->ni_ic;
321 
322 	/*
323 	 * Save the frame with an aging interval 4 times
324 	 * the listen interval specified by the station.
325 	 * Frames that sit around too long are reclaimed
326 	 * using this information.
327 	 * XXX handle overflow?
328 	 * XXX per/vap beacon interval?
329 	 */
330 	m->m_pkthdr.rcvif = (void *)(uintptr_t)
331 	    ieee80211_mac_hash(ic, ni->ni_macaddr);
332 	(void) ieee80211_ageq_append(&ic->ic_stageq, m,
333 	    ((ni->ni_intval * ic->ic_lintval) << 2) / 1024);
334 	ieee80211_notify_wds_discover(ni);
335 }
336 
337 /*
338  * IEEE80211_M_WDS vap state machine handler.
339  */
340 static int
341 wds_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
342 {
343 	struct ieee80211com *ic = vap->iv_ic;
344 	struct ieee80211_node *ni;
345 	enum ieee80211_state ostate;
346 	int error;
347 
348 	IEEE80211_LOCK_ASSERT(ic);
349 
350 	ostate = vap->iv_state;
351 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s\n", __func__,
352 		ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
353 	vap->iv_state = nstate;			/* state transition */
354 	callout_stop(&vap->iv_mgtsend);		/* XXX callout_drain */
355 	if (ostate != IEEE80211_S_SCAN)
356 		ieee80211_cancel_scan(vap);	/* background scan */
357 	ni = vap->iv_bss;			/* NB: no reference held */
358 	error = 0;
359 	switch (nstate) {
360 	case IEEE80211_S_INIT:
361 		switch (ostate) {
362 		case IEEE80211_S_SCAN:
363 			ieee80211_cancel_scan(vap);
364 			break;
365 		default:
366 			break;
367 		}
368 		if (ostate != IEEE80211_S_INIT) {
369 			/* NB: optimize INIT -> INIT case */
370 			ieee80211_reset_bss(vap);
371 		}
372 		break;
373 	case IEEE80211_S_SCAN:
374 		switch (ostate) {
375 		case IEEE80211_S_INIT:
376 			ieee80211_check_scan_current(vap);
377 			break;
378 		default:
379 			break;
380 		}
381 		break;
382 	case IEEE80211_S_RUN:
383 		if (ostate == IEEE80211_S_INIT) {
384 			/*
385 			 * Already have a channel; bypass the scan
386 			 * and startup immediately.
387 			 */
388 			error = ieee80211_create_wds(vap, ic->ic_curchan);
389 		}
390 		break;
391 	default:
392 		break;
393 	}
394 	return error;
395 }
396 
397 /*
398  * Process a received frame.  The node associated with the sender
399  * should be supplied.  If nothing was found in the node table then
400  * the caller is assumed to supply a reference to iv_bss instead.
401  * The RSSI and a timestamp are also supplied.  The RSSI data is used
402  * during AP scanning to select a AP to associate with; it can have
403  * any units so long as values have consistent units and higher values
404  * mean ``better signal''.  The receive timestamp is currently not used
405  * by the 802.11 layer.
406  */
407 static int
408 wds_input(struct ieee80211_node *ni, struct mbuf *m,
409     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
410 {
411 	struct ieee80211vap *vap = ni->ni_vap;
412 	struct ieee80211com *ic = ni->ni_ic;
413 	struct ifnet *ifp = vap->iv_ifp;
414 	struct ieee80211_frame *wh;
415 	struct ieee80211_key *key;
416 	struct ether_header *eh;
417 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
418 	uint8_t dir, type, subtype, qos;
419 	uint16_t rxseq;
420 
421 	if (m->m_flags & M_AMPDU_MPDU) {
422 		/*
423 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
424 		 * w/ M_AMPDU_MPDU marked have already passed through
425 		 * here but were received out of order and been held on
426 		 * the reorder queue.  When resubmitted they are marked
427 		 * with the M_AMPDU_MPDU flag and we can bypass most of
428 		 * the normal processing.
429 		 */
430 		wh = mtod(m, struct ieee80211_frame *);
431 		type = IEEE80211_FC0_TYPE_DATA;
432 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
433 		subtype = IEEE80211_FC0_SUBTYPE_QOS;
434 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
435 		goto resubmit_ampdu;
436 	}
437 
438 	KASSERT(ni != NULL, ("null node"));
439 
440 	type = -1;			/* undefined */
441 
442 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
443 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
444 		    ni->ni_macaddr, NULL,
445 		    "too short (1): len %u", m->m_pkthdr.len);
446 		vap->iv_stats.is_rx_tooshort++;
447 		goto out;
448 	}
449 	/*
450 	 * Bit of a cheat here, we use a pointer for a 3-address
451 	 * frame format but don't reference fields past outside
452 	 * ieee80211_frame_min w/o first validating the data is
453 	 * present.
454 	 */
455 	wh = mtod(m, struct ieee80211_frame *);
456 
457 	if (!IEEE80211_IS_MULTICAST(wh->i_addr1))
458 		ni->ni_inact = ni->ni_inact_reload;
459 
460 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
461 	    IEEE80211_FC0_VERSION_0) {
462 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
463 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
464 		    wh->i_fc[0], wh->i_fc[1]);
465 		vap->iv_stats.is_rx_badversion++;
466 		goto err;
467 	}
468 
469 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
470 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
471 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
472 
473 	/* NB: WDS vap's do not scan */
474 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_addr4)) {
475 		IEEE80211_DISCARD_MAC(vap,
476 		    IEEE80211_MSG_ANY, ni->ni_macaddr, NULL,
477 		    "too short (3): len %u", m->m_pkthdr.len);
478 		vap->iv_stats.is_rx_tooshort++;
479 		goto out;
480 	}
481 	/* NB: the TA is implicitly verified by finding the wds peer node */
482 	if (!IEEE80211_ADDR_EQ(wh->i_addr1, vap->iv_myaddr) &&
483 	    !IEEE80211_ADDR_EQ(wh->i_addr1, ifp->if_broadcastaddr)) {
484 		/* not interested in */
485 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
486 		    wh->i_addr1, NULL, "%s", "not to bss");
487 		vap->iv_stats.is_rx_wrongbss++;
488 		goto out;
489 	}
490 	IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
491 	ni->ni_noise = nf;
492 	if (IEEE80211_HAS_SEQ(type, subtype)) {
493 		uint8_t tid = ieee80211_gettid(wh);
494 		if (IEEE80211_QOS_HAS_SEQ(wh) &&
495 		    TID_TO_WME_AC(tid) >= WME_AC_VI)
496 			ic->ic_wme.wme_hipri_traffic++;
497 		rxseq = le16toh(*(uint16_t *)wh->i_seq);
498 		if (! ieee80211_check_rxseq(ni, wh)) {
499 			/* duplicate, discard */
500 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
501 			    wh->i_addr1, "duplicate",
502 			    "seqno <%u,%u> fragno <%u,%u> tid %u",
503 			    rxseq >> IEEE80211_SEQ_SEQ_SHIFT,
504 			    ni->ni_rxseqs[tid] >> IEEE80211_SEQ_SEQ_SHIFT,
505 			    rxseq & IEEE80211_SEQ_FRAG_MASK,
506 			    ni->ni_rxseqs[tid] & IEEE80211_SEQ_FRAG_MASK,
507 			    tid);
508 			vap->iv_stats.is_rx_dup++;
509 			IEEE80211_NODE_STAT(ni, rx_dup);
510 			goto out;
511 		}
512 		ni->ni_rxseqs[tid] = rxseq;
513 	}
514 	switch (type) {
515 	case IEEE80211_FC0_TYPE_DATA:
516 		hdrspace = ieee80211_hdrspace(ic, wh);
517 		if (m->m_len < hdrspace &&
518 		    (m = m_pullup(m, hdrspace)) == NULL) {
519 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
520 			    ni->ni_macaddr, NULL,
521 			    "data too short: expecting %u", hdrspace);
522 			vap->iv_stats.is_rx_tooshort++;
523 			goto out;		/* XXX */
524 		}
525 		if (dir != IEEE80211_FC1_DIR_DSTODS) {
526 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
527 			    wh, "data", "incorrect dir 0x%x", dir);
528 			vap->iv_stats.is_rx_wrongdir++;
529 			goto out;
530 		}
531 		/*
532 		 * Only legacy WDS traffic should take this path.
533 		 */
534 		if ((vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0) {
535 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
536 			    wh, "data", "%s", "not legacy wds");
537 			vap->iv_stats.is_rx_wrongdir++;/*XXX*/
538 			goto out;
539 		}
540 		/*
541 		 * Handle A-MPDU re-ordering.  If the frame is to be
542 		 * processed directly then ieee80211_ampdu_reorder
543 		 * will return 0; otherwise it has consumed the mbuf
544 		 * and we should do nothing more with it.
545 		 */
546 		if ((m->m_flags & M_AMPDU) &&
547 		    ieee80211_ampdu_reorder(ni, m) != 0) {
548 			m = NULL;
549 			goto out;
550 		}
551 	resubmit_ampdu:
552 
553 		/*
554 		 * Handle privacy requirements.  Note that we
555 		 * must not be preempted from here until after
556 		 * we (potentially) call ieee80211_crypto_demic;
557 		 * otherwise we may violate assumptions in the
558 		 * crypto cipher modules used to do delayed update
559 		 * of replay sequence numbers.
560 		 */
561 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
562 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
563 				/*
564 				 * Discard encrypted frames when privacy is off.
565 				 */
566 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
567 				    wh, "WEP", "%s", "PRIVACY off");
568 				vap->iv_stats.is_rx_noprivacy++;
569 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
570 				goto out;
571 			}
572 			key = ieee80211_crypto_decap(ni, m, hdrspace);
573 			if (key == NULL) {
574 				/* NB: stats+msgs handled in crypto_decap */
575 				IEEE80211_NODE_STAT(ni, rx_wepfail);
576 				goto out;
577 			}
578 			wh = mtod(m, struct ieee80211_frame *);
579 			wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
580 		} else {
581 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
582 			key = NULL;
583 		}
584 
585 		/*
586 		 * Save QoS bits for use below--before we strip the header.
587 		 */
588 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
589 			qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
590 			    ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
591 			    ((struct ieee80211_qosframe *)wh)->i_qos[0];
592 		} else
593 			qos = 0;
594 
595 		/*
596 		 * Next up, any fragmentation.
597 		 */
598 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
599 			m = ieee80211_defrag(ni, m, hdrspace);
600 			if (m == NULL) {
601 				/* Fragment dropped or frame not complete yet */
602 				goto out;
603 			}
604 		}
605 		wh = NULL;		/* no longer valid, catch any uses */
606 
607 		/*
608 		 * Next strip any MSDU crypto bits.
609 		 */
610 		if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
611 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
612 			    ni->ni_macaddr, "data", "%s", "demic error");
613 			vap->iv_stats.is_rx_demicfail++;
614 			IEEE80211_NODE_STAT(ni, rx_demicfail);
615 			goto out;
616 		}
617 
618 		/* copy to listener after decrypt */
619 		if (ieee80211_radiotap_active_vap(vap))
620 			ieee80211_radiotap_rx(vap, m);
621 		need_tap = 0;
622 
623 		/*
624 		 * Finally, strip the 802.11 header.
625 		 */
626 		m = ieee80211_decap(vap, m, hdrspace);
627 		if (m == NULL) {
628 			/* XXX mask bit to check for both */
629 			/* don't count Null data frames as errors */
630 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
631 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
632 				goto out;
633 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
634 			    ni->ni_macaddr, "data", "%s", "decap error");
635 			vap->iv_stats.is_rx_decap++;
636 			IEEE80211_NODE_STAT(ni, rx_decap);
637 			goto err;
638 		}
639 		eh = mtod(m, struct ether_header *);
640 		if (!ieee80211_node_is_authorized(ni)) {
641 			/*
642 			 * Deny any non-PAE frames received prior to
643 			 * authorization.  For open/shared-key
644 			 * authentication the port is mark authorized
645 			 * after authentication completes.  For 802.1x
646 			 * the port is not marked authorized by the
647 			 * authenticator until the handshake has completed.
648 			 */
649 			if (eh->ether_type != htons(ETHERTYPE_PAE)) {
650 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
651 				    eh->ether_shost, "data",
652 				    "unauthorized port: ether type 0x%x len %u",
653 				    eh->ether_type, m->m_pkthdr.len);
654 				vap->iv_stats.is_rx_unauth++;
655 				IEEE80211_NODE_STAT(ni, rx_unauth);
656 				goto err;
657 			}
658 		} else {
659 			/*
660 			 * When denying unencrypted frames, discard
661 			 * any non-PAE frames received without encryption.
662 			 */
663 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
664 			    (key == NULL && (m->m_flags & M_WEP) == 0) &&
665 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
666 				/*
667 				 * Drop unencrypted frames.
668 				 */
669 				vap->iv_stats.is_rx_unencrypted++;
670 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
671 				goto out;
672 			}
673 		}
674 		/* XXX require HT? */
675 		if (qos & IEEE80211_QOS_AMSDU) {
676 			m = ieee80211_decap_amsdu(ni, m);
677 			if (m == NULL)
678 				return IEEE80211_FC0_TYPE_DATA;
679 		} else {
680 #ifdef IEEE80211_SUPPORT_SUPERG
681 			m = ieee80211_decap_fastframe(vap, ni, m);
682 			if (m == NULL)
683 				return IEEE80211_FC0_TYPE_DATA;
684 #endif
685 		}
686 		ieee80211_deliver_data(vap, ni, m);
687 		return IEEE80211_FC0_TYPE_DATA;
688 
689 	case IEEE80211_FC0_TYPE_MGT:
690 		vap->iv_stats.is_rx_mgmt++;
691 		IEEE80211_NODE_STAT(ni, rx_mgmt);
692 		if (dir != IEEE80211_FC1_DIR_NODS) {
693 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
694 			    wh, "data", "incorrect dir 0x%x", dir);
695 			vap->iv_stats.is_rx_wrongdir++;
696 			goto err;
697 		}
698 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
699 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
700 			    ni->ni_macaddr, "mgt", "too short: len %u",
701 			    m->m_pkthdr.len);
702 			vap->iv_stats.is_rx_tooshort++;
703 			goto out;
704 		}
705 #ifdef IEEE80211_DEBUG
706 		if (ieee80211_msg_debug(vap) || ieee80211_msg_dumppkts(vap)) {
707 			if_printf(ifp, "received %s from %s rssi %d\n",
708 			    ieee80211_mgt_subtype_name[subtype >>
709 				IEEE80211_FC0_SUBTYPE_SHIFT],
710 			    ether_sprintf(wh->i_addr2), rssi);
711 		}
712 #endif
713 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
714 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
715 			    wh, NULL, "%s", "WEP set but not permitted");
716 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
717 			goto out;
718 		}
719 		vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
720 		goto out;
721 
722 	case IEEE80211_FC0_TYPE_CTL:
723 		vap->iv_stats.is_rx_ctl++;
724 		IEEE80211_NODE_STAT(ni, rx_ctrl);
725 		goto out;
726 
727 	default:
728 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
729 		    wh, "bad", "frame type 0x%x", type);
730 		/* should not come here */
731 		break;
732 	}
733 err:
734 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
735 out:
736 	if (m != NULL) {
737 		if (need_tap && ieee80211_radiotap_active_vap(vap))
738 			ieee80211_radiotap_rx(vap, m);
739 		m_freem(m);
740 	}
741 	return type;
742 }
743 
744 static void
745 wds_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0, int subtype,
746     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
747 {
748 	struct ieee80211vap *vap = ni->ni_vap;
749 	struct ieee80211com *ic = ni->ni_ic;
750 	struct ieee80211_frame *wh;
751 	u_int8_t *frm, *efrm;
752 
753 	wh = mtod(m0, struct ieee80211_frame *);
754 	frm = (u_int8_t *)&wh[1];
755 	efrm = mtod(m0, u_int8_t *) + m0->m_len;
756 	switch (subtype) {
757 	case IEEE80211_FC0_SUBTYPE_ACTION:
758 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
759 		if (ni == vap->iv_bss) {
760 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
761 			    wh, NULL, "%s", "unknown node");
762 			vap->iv_stats.is_rx_mgtdiscard++;
763 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1)) {
764 			/* NB: not interested in multicast frames. */
765 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
766 			    wh, NULL, "%s", "not for us");
767 			vap->iv_stats.is_rx_mgtdiscard++;
768 		} else if (vap->iv_state != IEEE80211_S_RUN) {
769 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
770 			    wh, NULL, "wrong state %s",
771 			    ieee80211_state_name[vap->iv_state]);
772 			vap->iv_stats.is_rx_mgtdiscard++;
773 		} else {
774 			if (ieee80211_parse_action(ni, m0) == 0)
775 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
776 		}
777 		break;
778 
779 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
780 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
781 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
782 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
783 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
784 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
785 	case IEEE80211_FC0_SUBTYPE_BEACON:
786 	case IEEE80211_FC0_SUBTYPE_ATIM:
787 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
788 	case IEEE80211_FC0_SUBTYPE_AUTH:
789 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
790 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
791 		    wh, NULL, "%s", "not handled");
792 		vap->iv_stats.is_rx_mgtdiscard++;
793 		break;
794 
795 	default:
796 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
797 		    wh, "mgt", "subtype 0x%x not handled", subtype);
798 		vap->iv_stats.is_rx_badsubtype++;
799 		break;
800 	}
801 }
802