xref: /freebsd/sys/net80211/ieee80211_adhoc.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
1 /*-
2  * Copyright (c) 2007-2009 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 IBSS 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_adhoc.h>
60 #include <net80211/ieee80211_input.h>
61 #ifdef IEEE80211_SUPPORT_SUPERG
62 #include <net80211/ieee80211_superg.h>
63 #endif
64 #ifdef IEEE80211_SUPPORT_TDMA
65 #include <net80211/ieee80211_tdma.h>
66 #endif
67 #include <net80211/ieee80211_sta.h>
68 
69 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
70 
71 static	void adhoc_vattach(struct ieee80211vap *);
72 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
73 static int adhoc_input(struct ieee80211_node *, struct mbuf *,
74 	    const struct ieee80211_rx_stats *, int, int);
75 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
76 	int subtype, const struct ieee80211_rx_stats *, int, int);
77 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
78 	    int subtype, const struct ieee80211_rx_stats *rxs, int, int);
79 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
80 
81 void
82 ieee80211_adhoc_attach(struct ieee80211com *ic)
83 {
84 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
85 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
86 }
87 
88 void
89 ieee80211_adhoc_detach(struct ieee80211com *ic)
90 {
91 }
92 
93 static void
94 adhoc_vdetach(struct ieee80211vap *vap)
95 {
96 }
97 
98 static void
99 adhoc_vattach(struct ieee80211vap *vap)
100 {
101 	vap->iv_newstate = adhoc_newstate;
102 	vap->iv_input = adhoc_input;
103 	if (vap->iv_opmode == IEEE80211_M_IBSS)
104 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
105 	else
106 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
107 	vap->iv_recv_ctl = adhoc_recv_ctl;
108 	vap->iv_opdetach = adhoc_vdetach;
109 #ifdef IEEE80211_SUPPORT_TDMA
110 	/*
111 	 * Throw control to tdma support.  Note we do this
112 	 * after setting up our callbacks so it can piggyback
113 	 * on top of us.
114 	 */
115 	if (vap->iv_caps & IEEE80211_C_TDMA)
116 		ieee80211_tdma_vattach(vap);
117 #endif
118 }
119 
120 static void
121 sta_leave(void *arg, struct ieee80211_node *ni)
122 {
123 	struct ieee80211vap *vap = arg;
124 
125 	if (ni->ni_vap == vap && ni != vap->iv_bss)
126 		ieee80211_node_leave(ni);
127 }
128 
129 /*
130  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
131  */
132 static int
133 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
134 {
135 	struct ieee80211com *ic = vap->iv_ic;
136 	struct ieee80211_node *ni;
137 	enum ieee80211_state ostate;
138 
139 	IEEE80211_LOCK_ASSERT(vap->iv_ic);
140 
141 	ostate = vap->iv_state;
142 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
143 	    __func__, ieee80211_state_name[ostate],
144 	    ieee80211_state_name[nstate], arg);
145 	vap->iv_state = nstate;			/* state transition */
146 	if (ostate != IEEE80211_S_SCAN)
147 		ieee80211_cancel_scan(vap);	/* background scan */
148 	ni = vap->iv_bss;			/* NB: no reference held */
149 	switch (nstate) {
150 	case IEEE80211_S_INIT:
151 		switch (ostate) {
152 		case IEEE80211_S_SCAN:
153 			ieee80211_cancel_scan(vap);
154 			break;
155 		default:
156 			break;
157 		}
158 		if (ostate != IEEE80211_S_INIT) {
159 			/* NB: optimize INIT -> INIT case */
160 			ieee80211_reset_bss(vap);
161 		}
162 		break;
163 	case IEEE80211_S_SCAN:
164 		switch (ostate) {
165 		case IEEE80211_S_RUN:		/* beacon miss */
166 			/* purge station table; entries are stale */
167 			ieee80211_iterate_nodes(&ic->ic_sta, sta_leave, vap);
168 			/* fall thru... */
169 		case IEEE80211_S_INIT:
170 			if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
171 			    !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
172 				/*
173 				 * Already have a channel; bypass the
174 				 * scan and startup immediately.
175 				 */
176 				ieee80211_create_ibss(vap,
177 				    ieee80211_ht_adjust_channel(ic,
178 				    vap->iv_des_chan, vap->iv_flags_ht));
179 				break;
180 			}
181 			/*
182 			 * Initiate a scan.  We can come here as a result
183 			 * of an IEEE80211_IOC_SCAN_REQ too in which case
184 			 * the vap will be marked with IEEE80211_FEXT_SCANREQ
185 			 * and the scan request parameters will be present
186 			 * in iv_scanreq.  Otherwise we do the default.
187 			 */
188 			if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
189 				ieee80211_check_scan(vap,
190 				    vap->iv_scanreq_flags,
191 				    vap->iv_scanreq_duration,
192 				    vap->iv_scanreq_mindwell,
193 				    vap->iv_scanreq_maxdwell,
194 				    vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
195 				vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
196 			} else
197 				ieee80211_check_scan_current(vap);
198 			break;
199 		case IEEE80211_S_SCAN:
200 			/*
201 			 * This can happen because of a change in state
202 			 * that requires a reset.  Trigger a new scan
203 			 * unless we're in manual roaming mode in which
204 			 * case an application must issue an explicit request.
205 			 */
206 			if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
207 				ieee80211_check_scan_current(vap);
208 			break;
209 		default:
210 			goto invalid;
211 		}
212 		break;
213 	case IEEE80211_S_RUN:
214 		if (vap->iv_flags & IEEE80211_F_WPA) {
215 			/* XXX validate prerequisites */
216 		}
217 		switch (ostate) {
218 		case IEEE80211_S_SCAN:
219 #ifdef IEEE80211_DEBUG
220 			if (ieee80211_msg_debug(vap)) {
221 				ieee80211_note(vap,
222 				    "synchronized with %s ssid ",
223 				    ether_sprintf(ni->ni_bssid));
224 				ieee80211_print_essid(vap->iv_bss->ni_essid,
225 				    ni->ni_esslen);
226 				/* XXX MCS/HT */
227 				printf(" channel %d start %uMb\n",
228 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
229 				    IEEE80211_RATE2MBS(ni->ni_txrate));
230 			}
231 #endif
232 			break;
233 		case IEEE80211_S_RUN:	/* IBSS merge */
234 			break;
235 		default:
236 			goto invalid;
237 		}
238 		/*
239 		 * When 802.1x is not in use mark the port authorized
240 		 * at this point so traffic can flow.
241 		 */
242 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
243 			ieee80211_node_authorize(ni);
244 		/*
245 		 * Fake association when joining an existing bss.
246 		 */
247 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
248 		    ic->ic_newassoc != NULL)
249 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
250 		break;
251 	case IEEE80211_S_SLEEP:
252 		vap->iv_sta_ps(vap, 0);
253 		break;
254 	default:
255 	invalid:
256 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
257 		    "%s: unexpected state transition %s -> %s\n", __func__,
258 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
259 		break;
260 	}
261 	return 0;
262 }
263 
264 /*
265  * Decide if a received management frame should be
266  * printed when debugging is enabled.  This filters some
267  * of the less interesting frames that come frequently
268  * (e.g. beacons).
269  */
270 static __inline int
271 doprint(struct ieee80211vap *vap, int subtype)
272 {
273 	switch (subtype) {
274 	case IEEE80211_FC0_SUBTYPE_BEACON:
275 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
276 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
277 		return 1;
278 	}
279 	return 1;
280 }
281 
282 /*
283  * Process a received frame.  The node associated with the sender
284  * should be supplied.  If nothing was found in the node table then
285  * the caller is assumed to supply a reference to iv_bss instead.
286  * The RSSI and a timestamp are also supplied.  The RSSI data is used
287  * during AP scanning to select a AP to associate with; it can have
288  * any units so long as values have consistent units and higher values
289  * mean ``better signal''.  The receive timestamp is currently not used
290  * by the 802.11 layer.
291  */
292 static int
293 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
294     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
295 {
296 	struct ieee80211vap *vap = ni->ni_vap;
297 	struct ieee80211com *ic = ni->ni_ic;
298 	struct ifnet *ifp = vap->iv_ifp;
299 	struct ieee80211_frame *wh;
300 	struct ieee80211_key *key;
301 	struct ether_header *eh;
302 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
303 	uint8_t dir, type, subtype, qos;
304 	uint8_t *bssid;
305 
306 	if (m->m_flags & M_AMPDU_MPDU) {
307 		/*
308 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
309 		 * w/ M_AMPDU_MPDU marked have already passed through
310 		 * here but were received out of order and been held on
311 		 * the reorder queue.  When resubmitted they are marked
312 		 * with the M_AMPDU_MPDU flag and we can bypass most of
313 		 * the normal processing.
314 		 */
315 		wh = mtod(m, struct ieee80211_frame *);
316 		type = IEEE80211_FC0_TYPE_DATA;
317 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
318 		subtype = IEEE80211_FC0_SUBTYPE_QOS;
319 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
320 		goto resubmit_ampdu;
321 	}
322 
323 	KASSERT(ni != NULL, ("null node"));
324 	ni->ni_inact = ni->ni_inact_reload;
325 
326 	type = -1;			/* undefined */
327 
328 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
329 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
330 		    ni->ni_macaddr, NULL,
331 		    "too short (1): len %u", m->m_pkthdr.len);
332 		vap->iv_stats.is_rx_tooshort++;
333 		goto out;
334 	}
335 	/*
336 	 * Bit of a cheat here, we use a pointer for a 3-address
337 	 * frame format but don't reference fields past outside
338 	 * ieee80211_frame_min w/o first validating the data is
339 	 * present.
340 	 */
341 	wh = mtod(m, struct ieee80211_frame *);
342 
343 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
344 	    IEEE80211_FC0_VERSION_0) {
345 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
346 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
347 		    wh->i_fc[0], wh->i_fc[1]);
348 		vap->iv_stats.is_rx_badversion++;
349 		goto err;
350 	}
351 
352 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
353 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
354 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
355 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
356 		if (dir != IEEE80211_FC1_DIR_NODS)
357 			bssid = wh->i_addr1;
358 		else if (type == IEEE80211_FC0_TYPE_CTL)
359 			bssid = wh->i_addr1;
360 		else {
361 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
362 				IEEE80211_DISCARD_MAC(vap,
363 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
364 				    NULL, "too short (2): len %u",
365 				    m->m_pkthdr.len);
366 				vap->iv_stats.is_rx_tooshort++;
367 				goto out;
368 			}
369 			bssid = wh->i_addr3;
370 		}
371 		/*
372 		 * Validate the bssid.
373 		 */
374 		if (!IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
375 		    !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
376 			/* not interested in */
377 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
378 			    bssid, NULL, "%s", "not to bss");
379 			vap->iv_stats.is_rx_wrongbss++;
380 			goto out;
381 		}
382 		/*
383 		 * Data frame, cons up a node when it doesn't
384 		 * exist. This should probably done after an ACL check.
385 		 */
386 		if (type == IEEE80211_FC0_TYPE_DATA &&
387 		    ni == vap->iv_bss &&
388 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
389 			/*
390 			 * Beware of frames that come in too early; we
391 			 * can receive broadcast frames and creating sta
392 			 * entries will blow up because there is no bss
393 			 * channel yet.
394 			 */
395 			if (vap->iv_state != IEEE80211_S_RUN) {
396 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
397 				    wh, "data", "not in RUN state (%s)",
398 				    ieee80211_state_name[vap->iv_state]);
399 				vap->iv_stats.is_rx_badstate++;
400 				goto err;
401 			}
402 			/*
403 			 * Fake up a node for this newly
404 			 * discovered member of the IBSS.
405 			 */
406 			ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
407 			if (ni == NULL) {
408 				/* NB: stat kept for alloc failure */
409 				goto err;
410 			}
411 		}
412 		IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
413 		ni->ni_noise = nf;
414 		if (IEEE80211_HAS_SEQ(type, subtype) &&
415 		    IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
416 			uint8_t tid = ieee80211_gettid(wh);
417 			if (IEEE80211_QOS_HAS_SEQ(wh) &&
418 			    TID_TO_WME_AC(tid) >= WME_AC_VI)
419 				ic->ic_wme.wme_hipri_traffic++;
420 			if (! ieee80211_check_rxseq(ni, wh, bssid))
421 				goto out;
422 		}
423 	}
424 
425 	switch (type) {
426 	case IEEE80211_FC0_TYPE_DATA:
427 		hdrspace = ieee80211_hdrspace(ic, wh);
428 		if (m->m_len < hdrspace &&
429 		    (m = m_pullup(m, hdrspace)) == NULL) {
430 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
431 			    ni->ni_macaddr, NULL,
432 			    "data too short: expecting %u", hdrspace);
433 			vap->iv_stats.is_rx_tooshort++;
434 			goto out;		/* XXX */
435 		}
436 		if (dir != IEEE80211_FC1_DIR_NODS) {
437 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
438 			    wh, "data", "incorrect dir 0x%x", dir);
439 			vap->iv_stats.is_rx_wrongdir++;
440 			goto out;
441 		}
442 		/* XXX no power-save support */
443 
444 		/*
445 		 * Handle A-MPDU re-ordering.  If the frame is to be
446 		 * processed directly then ieee80211_ampdu_reorder
447 		 * will return 0; otherwise it has consumed the mbuf
448 		 * and we should do nothing more with it.
449 		 */
450 		if ((m->m_flags & M_AMPDU) &&
451 		    ieee80211_ampdu_reorder(ni, m) != 0) {
452 			m = NULL;
453 			goto out;
454 		}
455 	resubmit_ampdu:
456 
457 		/*
458 		 * Handle privacy requirements.  Note that we
459 		 * must not be preempted from here until after
460 		 * we (potentially) call ieee80211_crypto_demic;
461 		 * otherwise we may violate assumptions in the
462 		 * crypto cipher modules used to do delayed update
463 		 * of replay sequence numbers.
464 		 */
465 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
466 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
467 				/*
468 				 * Discard encrypted frames when privacy is off.
469 				 */
470 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
471 				    wh, "WEP", "%s", "PRIVACY off");
472 				vap->iv_stats.is_rx_noprivacy++;
473 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
474 				goto out;
475 			}
476 			key = ieee80211_crypto_decap(ni, m, hdrspace);
477 			if (key == NULL) {
478 				/* NB: stats+msgs handled in crypto_decap */
479 				IEEE80211_NODE_STAT(ni, rx_wepfail);
480 				goto out;
481 			}
482 			wh = mtod(m, struct ieee80211_frame *);
483 			wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
484 		} else {
485 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
486 			key = NULL;
487 		}
488 
489 		/*
490 		 * Save QoS bits for use below--before we strip the header.
491 		 */
492 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
493 			qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
494 			    ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
495 			    ((struct ieee80211_qosframe *)wh)->i_qos[0];
496 		} else
497 			qos = 0;
498 
499 		/*
500 		 * Next up, any fragmentation.
501 		 */
502 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
503 			m = ieee80211_defrag(ni, m, hdrspace);
504 			if (m == NULL) {
505 				/* Fragment dropped or frame not complete yet */
506 				goto out;
507 			}
508 		}
509 		wh = NULL;		/* no longer valid, catch any uses */
510 
511 		/*
512 		 * Next strip any MSDU crypto bits.
513 		 */
514 		if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
515 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
516 			    ni->ni_macaddr, "data", "%s", "demic error");
517 			vap->iv_stats.is_rx_demicfail++;
518 			IEEE80211_NODE_STAT(ni, rx_demicfail);
519 			goto out;
520 		}
521 
522 		/* copy to listener after decrypt */
523 		if (ieee80211_radiotap_active_vap(vap))
524 			ieee80211_radiotap_rx(vap, m);
525 		need_tap = 0;
526 
527 		/*
528 		 * Finally, strip the 802.11 header.
529 		 */
530 		m = ieee80211_decap(vap, m, hdrspace);
531 		if (m == NULL) {
532 			/* XXX mask bit to check for both */
533 			/* don't count Null data frames as errors */
534 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
535 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
536 				goto out;
537 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
538 			    ni->ni_macaddr, "data", "%s", "decap error");
539 			vap->iv_stats.is_rx_decap++;
540 			IEEE80211_NODE_STAT(ni, rx_decap);
541 			goto err;
542 		}
543 		eh = mtod(m, struct ether_header *);
544 		if (!ieee80211_node_is_authorized(ni)) {
545 			/*
546 			 * Deny any non-PAE frames received prior to
547 			 * authorization.  For open/shared-key
548 			 * authentication the port is mark authorized
549 			 * after authentication completes.  For 802.1x
550 			 * the port is not marked authorized by the
551 			 * authenticator until the handshake has completed.
552 			 */
553 			if (eh->ether_type != htons(ETHERTYPE_PAE)) {
554 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
555 				    eh->ether_shost, "data",
556 				    "unauthorized port: ether type 0x%x len %u",
557 				    eh->ether_type, m->m_pkthdr.len);
558 				vap->iv_stats.is_rx_unauth++;
559 				IEEE80211_NODE_STAT(ni, rx_unauth);
560 				goto err;
561 			}
562 		} else {
563 			/*
564 			 * When denying unencrypted frames, discard
565 			 * any non-PAE frames received without encryption.
566 			 */
567 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
568 			    (key == NULL && (m->m_flags & M_WEP) == 0) &&
569 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
570 				/*
571 				 * Drop unencrypted frames.
572 				 */
573 				vap->iv_stats.is_rx_unencrypted++;
574 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
575 				goto out;
576 			}
577 		}
578 		/* XXX require HT? */
579 		if (qos & IEEE80211_QOS_AMSDU) {
580 			m = ieee80211_decap_amsdu(ni, m);
581 			if (m == NULL)
582 				return IEEE80211_FC0_TYPE_DATA;
583 		} else {
584 #ifdef IEEE80211_SUPPORT_SUPERG
585 			m = ieee80211_decap_fastframe(vap, ni, m);
586 			if (m == NULL)
587 				return IEEE80211_FC0_TYPE_DATA;
588 #endif
589 		}
590 		if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
591 			ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
592 		else
593 			ieee80211_deliver_data(vap, ni, m);
594 		return IEEE80211_FC0_TYPE_DATA;
595 
596 	case IEEE80211_FC0_TYPE_MGT:
597 		vap->iv_stats.is_rx_mgmt++;
598 		IEEE80211_NODE_STAT(ni, rx_mgmt);
599 		if (dir != IEEE80211_FC1_DIR_NODS) {
600 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
601 			    wh, "data", "incorrect dir 0x%x", dir);
602 			vap->iv_stats.is_rx_wrongdir++;
603 			goto err;
604 		}
605 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
606 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
607 			    ni->ni_macaddr, "mgt", "too short: len %u",
608 			    m->m_pkthdr.len);
609 			vap->iv_stats.is_rx_tooshort++;
610 			goto out;
611 		}
612 #ifdef IEEE80211_DEBUG
613 		if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
614 		    ieee80211_msg_dumppkts(vap)) {
615 			if_printf(ifp, "received %s from %s rssi %d\n",
616 			    ieee80211_mgt_subtype_name(subtype),
617 			    ether_sprintf(wh->i_addr2), rssi);
618 		}
619 #endif
620 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
621 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
622 			    wh, NULL, "%s", "WEP set but not permitted");
623 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
624 			goto out;
625 		}
626 		vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
627 		goto out;
628 
629 	case IEEE80211_FC0_TYPE_CTL:
630 		vap->iv_stats.is_rx_ctl++;
631 		IEEE80211_NODE_STAT(ni, rx_ctrl);
632 		vap->iv_recv_ctl(ni, m, subtype);
633 		goto out;
634 
635 	default:
636 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
637 		    wh, "bad", "frame type 0x%x", type);
638 		/* should not come here */
639 		break;
640 	}
641 err:
642 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
643 out:
644 	if (m != NULL) {
645 		if (need_tap && ieee80211_radiotap_active_vap(vap))
646 			ieee80211_radiotap_rx(vap, m);
647 		m_freem(m);
648 	}
649 	return type;
650 }
651 
652 static int
653 is11bclient(const uint8_t *rates, const uint8_t *xrates)
654 {
655 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
656 	int i;
657 
658 	/* NB: the 11b clients we care about will not have xrates */
659 	if (xrates != NULL || rates == NULL)
660 		return 0;
661 	for (i = 0; i < rates[1]; i++) {
662 		int r = rates[2+i] & IEEE80211_RATE_VAL;
663 		if (r > 2*11 || ((1<<r) & brates) == 0)
664 			return 0;
665 	}
666 	return 1;
667 }
668 
669 static void
670 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
671 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
672 {
673 	struct ieee80211vap *vap = ni->ni_vap;
674 	struct ieee80211com *ic = ni->ni_ic;
675 	struct ieee80211_channel *rxchan = ic->ic_curchan;
676 	struct ieee80211_frame *wh;
677 	uint8_t *frm, *efrm;
678 	uint8_t *ssid, *rates, *xrates;
679 #if 0
680 	int ht_state_change = 0;
681 #endif
682 
683 	wh = mtod(m0, struct ieee80211_frame *);
684 	frm = (uint8_t *)&wh[1];
685 	efrm = mtod(m0, uint8_t *) + m0->m_len;
686 	switch (subtype) {
687 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
688 	case IEEE80211_FC0_SUBTYPE_BEACON: {
689 		struct ieee80211_scanparams scan;
690 		struct ieee80211_channel *c;
691 		/*
692 		 * We process beacon/probe response
693 		 * frames to discover neighbors.
694 		 */
695 		if (rxs != NULL) {
696 			c = ieee80211_lookup_channel_rxstatus(vap, rxs);
697 			if (c != NULL)
698 				rxchan = c;
699 		}
700 		if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
701 			return;
702 		/*
703 		 * Count frame now that we know it's to be processed.
704 		 */
705 		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
706 			vap->iv_stats.is_rx_beacon++;		/* XXX remove */
707 			IEEE80211_NODE_STAT(ni, rx_beacons);
708 		} else
709 			IEEE80211_NODE_STAT(ni, rx_proberesp);
710 		/*
711 		 * If scanning, just pass information to the scan module.
712 		 */
713 		if (ic->ic_flags & IEEE80211_F_SCAN) {
714 			if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
715 				/*
716 				 * Actively scanning a channel marked passive;
717 				 * send a probe request now that we know there
718 				 * is 802.11 traffic present.
719 				 *
720 				 * XXX check if the beacon we recv'd gives
721 				 * us what we need and suppress the probe req
722 				 */
723 				ieee80211_probe_curchan(vap, 1);
724 				ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
725 			}
726 			ieee80211_add_scan(vap, rxchan, &scan, wh,
727 			    subtype, rssi, nf);
728 			return;
729 		}
730 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
731 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
732 				/*
733 				 * Create a new entry in the neighbor table.
734 				 */
735 				ni = ieee80211_add_neighbor(vap, wh, &scan);
736 			} else if (ni->ni_capinfo == 0) {
737 				/*
738 				 * Update faked node created on transmit.
739 				 * Note this also updates the tsf.
740 				 */
741 				ieee80211_init_neighbor(ni, wh, &scan);
742 			} else {
743 				/*
744 				 * Record tsf for potential resync.
745 				 */
746 				memcpy(ni->ni_tstamp.data, scan.tstamp,
747 					sizeof(ni->ni_tstamp));
748 			}
749 			/*
750 			 * This isn't enabled yet - otherwise it would
751 			 * update the HT parameters and channel width
752 			 * from any node, which could lead to lots of
753 			 * strange behaviour if the 11n nodes aren't
754 			 * exactly configured to match.
755 			 */
756 #if 0
757 			if (scan.htcap != NULL && scan.htinfo != NULL &&
758 			    (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
759 				if (ieee80211_ht_updateparams(ni,
760 				    scan.htcap, scan.htinfo))
761 					ht_state_change = 1;
762 			}
763 #endif
764 			if (ni != NULL) {
765 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
766 				ni->ni_noise = nf;
767 			}
768 			/*
769 			 * Same here - the channel width change should
770 			 * be applied to the specific peer node, not
771 			 * to the ic.  Ie, the interface configuration
772 			 * should stay in its current channel width;
773 			 * but it should change the rate control and
774 			 * any queued frames for the given node only.
775 			 *
776 			 * Since there's no (current) way to inform
777 			 * the driver that a channel width change has
778 			 * occurred for a single node, just stub this
779 			 * out.
780 			 */
781 #if 0
782 			if (ht_state_change)
783 				ieee80211_update_chw(ic);
784 #endif
785 		}
786 		break;
787 	}
788 
789 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
790 		if (vap->iv_state != IEEE80211_S_RUN) {
791 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
792 			    wh, NULL, "wrong state %s",
793 			    ieee80211_state_name[vap->iv_state]);
794 			vap->iv_stats.is_rx_mgtdiscard++;
795 			return;
796 		}
797 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
798 			/* frame must be directed */
799 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
800 			    wh, NULL, "%s", "not unicast");
801 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
802 			return;
803 		}
804 
805 		/*
806 		 * prreq frame format
807 		 *	[tlv] ssid
808 		 *	[tlv] supported rates
809 		 *	[tlv] extended supported rates
810 		 */
811 		ssid = rates = xrates = NULL;
812 		while (efrm - frm > 1) {
813 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
814 			switch (*frm) {
815 			case IEEE80211_ELEMID_SSID:
816 				ssid = frm;
817 				break;
818 			case IEEE80211_ELEMID_RATES:
819 				rates = frm;
820 				break;
821 			case IEEE80211_ELEMID_XRATES:
822 				xrates = frm;
823 				break;
824 			}
825 			frm += frm[1] + 2;
826 		}
827 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
828 		if (xrates != NULL)
829 			IEEE80211_VERIFY_ELEMENT(xrates,
830 				IEEE80211_RATE_MAXSIZE - rates[1], return);
831 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
832 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
833 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
834 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
835 			    wh, NULL,
836 			    "%s", "no ssid with ssid suppression enabled");
837 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
838 			return;
839 		}
840 
841 		/* XXX find a better class or define it's own */
842 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
843 		    "%s", "recv probe req");
844 		/*
845 		 * Some legacy 11b clients cannot hack a complete
846 		 * probe response frame.  When the request includes
847 		 * only a bare-bones rate set, communicate this to
848 		 * the transmit side.
849 		 */
850 		ieee80211_send_proberesp(vap, wh->i_addr2,
851 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
852 		break;
853 
854 	case IEEE80211_FC0_SUBTYPE_ACTION:
855 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
856 		if ((ni == vap->iv_bss) &&
857 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
858 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
859 			    wh, NULL, "%s", "unknown node");
860 			vap->iv_stats.is_rx_mgtdiscard++;
861 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
862 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
863 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
864 			    wh, NULL, "%s", "not for us");
865 			vap->iv_stats.is_rx_mgtdiscard++;
866 		} else if (vap->iv_state != IEEE80211_S_RUN) {
867 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
868 			    wh, NULL, "wrong state %s",
869 			    ieee80211_state_name[vap->iv_state]);
870 			vap->iv_stats.is_rx_mgtdiscard++;
871 		} else {
872 			if (ieee80211_parse_action(ni, m0) == 0)
873 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
874 		}
875 		break;
876 
877 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
878 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
879 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
880 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
881 	case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
882 	case IEEE80211_FC0_SUBTYPE_ATIM:
883 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
884 	case IEEE80211_FC0_SUBTYPE_AUTH:
885 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
886 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
887 		    wh, NULL, "%s", "not handled");
888 		vap->iv_stats.is_rx_mgtdiscard++;
889 		break;
890 
891 	default:
892 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
893 		    wh, "mgt", "subtype 0x%x not handled", subtype);
894 		vap->iv_stats.is_rx_badsubtype++;
895 		break;
896 	}
897 }
898 #undef IEEE80211_VERIFY_LENGTH
899 #undef IEEE80211_VERIFY_ELEMENT
900 
901 static void
902 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
903 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
904 {
905 	struct ieee80211vap *vap = ni->ni_vap;
906 	struct ieee80211com *ic = ni->ni_ic;
907 	struct ieee80211_frame *wh;
908 
909 	/*
910 	 * Process management frames when scanning; useful for doing
911 	 * a site-survey.
912 	 */
913 	if (ic->ic_flags & IEEE80211_F_SCAN)
914 		adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
915 	else {
916 		wh = mtod(m0, struct ieee80211_frame *);
917 		switch (subtype) {
918 		case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
919 		case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
920 		case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
921 		case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
922 		case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
923 		case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
924 		case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
925 		case IEEE80211_FC0_SUBTYPE_BEACON:
926 		case IEEE80211_FC0_SUBTYPE_ATIM:
927 		case IEEE80211_FC0_SUBTYPE_DISASSOC:
928 		case IEEE80211_FC0_SUBTYPE_AUTH:
929 		case IEEE80211_FC0_SUBTYPE_DEAUTH:
930 		case IEEE80211_FC0_SUBTYPE_ACTION:
931 		case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
932 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
933 			     wh, NULL, "%s", "not handled");
934 			vap->iv_stats.is_rx_mgtdiscard++;
935 			break;
936 		default:
937 			IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
938 			     wh, "mgt", "subtype 0x%x not handled", subtype);
939 			vap->iv_stats.is_rx_badsubtype++;
940 			break;
941 		}
942 	}
943 }
944 
945 static void
946 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
947 {
948 
949 	switch (subtype) {
950 	case IEEE80211_FC0_SUBTYPE_BAR:
951 		ieee80211_recv_bar(ni, m);
952 		break;
953 	}
954 }
955