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  * $FreeBSD: head/sys/net80211/ieee80211_adhoc.c 203422 2010-02-03 10:07:43Z rpaulo $
26  */
27 
28 /*
29  * IEEE 802.11 IBSS mode support.
30  */
31 #include "opt_inet.h"
32 #include "opt_wlan.h"
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/mbuf.h>
37 #include <sys/malloc.h>
38 #include <sys/kernel.h>
39 
40 #include <sys/socket.h>
41 #include <sys/sockio.h>
42 #include <sys/endian.h>
43 #include <sys/errno.h>
44 #include <sys/proc.h>
45 #include <sys/sysctl.h>
46 
47 #include <net/if.h>
48 #include <net/if_media.h>
49 #include <net/if_llc.h>
50 #include <net/ethernet.h>
51 #include <net/route.h>
52 
53 #include <net/bpf.h>
54 
55 #include <netproto/802_11/ieee80211_var.h>
56 #include <netproto/802_11/ieee80211_adhoc.h>
57 #include <netproto/802_11/ieee80211_input.h>
58 #ifdef IEEE80211_SUPPORT_SUPERG
59 #include <netproto/802_11/ieee80211_superg.h>
60 #endif
61 #ifdef IEEE80211_SUPPORT_TDMA
62 #include <netproto/802_11/ieee80211_tdma.h>
63 #endif
64 
65 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
66 
67 static	void adhoc_vattach(struct ieee80211vap *);
68 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
69 static int adhoc_input(struct ieee80211_node *, struct mbuf *, int, int);
70 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
71 	int subtype, int, int);
72 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
73 	int subtype, int, int);
74 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
75 
76 void
77 ieee80211_adhoc_attach(struct ieee80211com *ic)
78 {
79 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
80 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
81 }
82 
83 void
84 ieee80211_adhoc_detach(struct ieee80211com *ic)
85 {
86 }
87 
88 static void
89 adhoc_vdetach(struct ieee80211vap *vap)
90 {
91 }
92 
93 static void
94 adhoc_vattach(struct ieee80211vap *vap)
95 {
96 	vap->iv_newstate = adhoc_newstate;
97 	vap->iv_input = adhoc_input;
98 	if (vap->iv_opmode == IEEE80211_M_IBSS)
99 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
100 	else
101 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
102 	vap->iv_recv_ctl = adhoc_recv_ctl;
103 	vap->iv_opdetach = adhoc_vdetach;
104 #ifdef IEEE80211_SUPPORT_TDMA
105 	/*
106 	 * Throw control to tdma support.  Note we do this
107 	 * after setting up our callbacks so it can piggyback
108 	 * on top of us.
109 	 */
110 	if (vap->iv_caps & IEEE80211_C_TDMA)
111 		ieee80211_tdma_vattach(vap);
112 #endif
113 }
114 
115 static void
116 sta_leave(void *arg, struct ieee80211_node *ni)
117 {
118 	struct ieee80211vap *vap = arg;
119 
120 	if (ni->ni_vap == vap && ni != vap->iv_bss)
121 		ieee80211_node_leave(ni);
122 }
123 
124 /*
125  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
126  */
127 static int
128 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
129 {
130 	struct ieee80211com *ic = vap->iv_ic;
131 	struct ieee80211_node *ni;
132 	enum ieee80211_state ostate;
133 
134 	ostate = vap->iv_state;
135 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
136 	    __func__, ieee80211_state_name[ostate],
137 	    ieee80211_state_name[nstate], arg);
138 	vap->iv_state = nstate;			/* state transition */
139 	if (ostate != IEEE80211_S_SCAN)
140 		ieee80211_cancel_scan(vap);	/* background scan */
141 	ni = vap->iv_bss;			/* NB: no reference held */
142 	switch (nstate) {
143 	case IEEE80211_S_INIT:
144 		switch (ostate) {
145 		case IEEE80211_S_SCAN:
146 			ieee80211_cancel_scan(vap);
147 			break;
148 		default:
149 			break;
150 		}
151 		if (ostate != IEEE80211_S_INIT) {
152 			/* NB: optimize INIT -> INIT case */
153 			ieee80211_reset_bss(vap);
154 		}
155 		break;
156 	case IEEE80211_S_SCAN:
157 		switch (ostate) {
158 		case IEEE80211_S_RUN:		/* beacon miss */
159 			/* purge station table; entries are stale */
160 			ieee80211_iterate_nodes(&ic->ic_sta, sta_leave, vap);
161 			/* fall thru... */
162 		case IEEE80211_S_INIT:
163 			if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
164 			    !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
165 				/*
166 				 * Already have a channel; bypass the
167 				 * scan and startup immediately.
168 				 */
169 				ieee80211_create_ibss(vap, vap->iv_des_chan);
170 				break;
171 			}
172 			/*
173 			 * Initiate a scan.  We can come here as a result
174 			 * of an IEEE80211_IOC_SCAN_REQ too in which case
175 			 * the vap will be marked with IEEE80211_FEXT_SCANREQ
176 			 * and the scan request parameters will be present
177 			 * in iv_scanreq.  Otherwise we do the default.
178 			 */
179 			if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
180 				ieee80211_check_scan(vap,
181 				    vap->iv_scanreq_flags,
182 				    vap->iv_scanreq_duration,
183 				    vap->iv_scanreq_mindwell,
184 				    vap->iv_scanreq_maxdwell,
185 				    vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
186 				vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
187 			} else
188 				ieee80211_check_scan_current(vap);
189 			break;
190 		case IEEE80211_S_SCAN:
191 			/*
192 			 * This can happen because of a change in state
193 			 * that requires a reset.  Trigger a new scan
194 			 * unless we're in manual roaming mode in which
195 			 * case an application must issue an explicit request.
196 			 */
197 			if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
198 				ieee80211_check_scan_current(vap);
199 			break;
200 		default:
201 			goto invalid;
202 		}
203 		break;
204 	case IEEE80211_S_RUN:
205 		if (vap->iv_flags & IEEE80211_F_WPA) {
206 			/* XXX validate prerequisites */
207 		}
208 		switch (ostate) {
209 		case IEEE80211_S_SCAN:
210 #ifdef IEEE80211_DEBUG
211 			if (ieee80211_msg_debug(vap)) {
212 				ieee80211_note(vap,
213 				    "synchronized with %6D ssid ",
214 				    ni->ni_bssid, ":");
215 				ieee80211_print_essid(vap->iv_bss->ni_essid,
216 				    ni->ni_esslen);
217 				/* XXX MCS/HT */
218 				kprintf(" channel %d start %uMb\n",
219 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
220 				    IEEE80211_RATE2MBS(ni->ni_txrate));
221 			}
222 #endif
223 			break;
224 		default:
225 			goto invalid;
226 		}
227 		/*
228 		 * When 802.1x is not in use mark the port authorized
229 		 * at this point so traffic can flow.
230 		 */
231 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
232 			ieee80211_node_authorize(ni);
233 		/*
234 		 * Fake association when joining an existing bss.
235 		 */
236 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
237 		    ic->ic_newassoc != NULL)
238 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
239 		break;
240 	case IEEE80211_S_SLEEP:
241 		ieee80211_sta_pwrsave(vap, 0);
242 		break;
243 	default:
244 	invalid:
245 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
246 		    "%s: unexpected state transition %s -> %s\n", __func__,
247 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
248 		break;
249 	}
250 	return 0;
251 }
252 
253 /*
254  * Decide if a received management frame should be
255  * printed when debugging is enabled.  This filters some
256  * of the less interesting frames that come frequently
257  * (e.g. beacons).
258  */
259 static __inline int
260 doprint(struct ieee80211vap *vap, int subtype)
261 {
262 	switch (subtype) {
263 	case IEEE80211_FC0_SUBTYPE_BEACON:
264 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
265 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
266 		return 1;
267 	}
268 	return 1;
269 }
270 
271 /*
272  * Process a received frame.  The node associated with the sender
273  * should be supplied.  If nothing was found in the node table then
274  * the caller is assumed to supply a reference to iv_bss instead.
275  * The RSSI and a timestamp are also supplied.  The RSSI data is used
276  * during AP scanning to select a AP to associate with; it can have
277  * any units so long as values have consistent units and higher values
278  * mean ``better signal''.  The receive timestamp is currently not used
279  * by the 802.11 layer.
280  */
281 static int
282 adhoc_input(struct ieee80211_node *ni, struct mbuf *m, int rssi, int nf)
283 {
284 #define	SEQ_LEQ(a,b)	((int)((a)-(b)) <= 0)
285 #define	HAS_SEQ(type)	((type & 0x4) == 0)
286 	struct ieee80211vap *vap = ni->ni_vap;
287 	struct ieee80211com *ic = ni->ni_ic;
288 	struct ifnet *ifp = vap->iv_ifp;
289 	struct ieee80211_frame *wh;
290 	struct ieee80211_key *key;
291 	struct ether_header *eh;
292 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
293 	uint8_t dir, type, subtype, qos;
294 	uint8_t *bssid;
295 	uint16_t rxseq;
296 
297 	if (m->m_flags & M_AMPDU_MPDU) {
298 		/*
299 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
300 		 * w/ M_AMPDU_MPDU marked have already passed through
301 		 * here but were received out of order and been held on
302 		 * the reorder queue.  When resubmitted they are marked
303 		 * with the M_AMPDU_MPDU flag and we can bypass most of
304 		 * the normal processing.
305 		 */
306 		wh = mtod(m, struct ieee80211_frame *);
307 		type = IEEE80211_FC0_TYPE_DATA;
308 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
309 		subtype = IEEE80211_FC0_SUBTYPE_QOS;
310 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
311 		goto resubmit_ampdu;
312 	}
313 
314 	KASSERT(ni != NULL, ("null node"));
315 	ni->ni_inact = ni->ni_inact_reload;
316 
317 	type = -1;			/* undefined */
318 
319 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
320 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
321 		    ni->ni_macaddr, NULL,
322 		    "too short (1): len %u", m->m_pkthdr.len);
323 		vap->iv_stats.is_rx_tooshort++;
324 		goto out;
325 	}
326 	/*
327 	 * Bit of a cheat here, we use a pointer for a 3-address
328 	 * frame format but don't reference fields past outside
329 	 * ieee80211_frame_min w/o first validating the data is
330 	 * present.
331 	 */
332 	wh = mtod(m, struct ieee80211_frame *);
333 
334 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
335 	    IEEE80211_FC0_VERSION_0) {
336 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
337 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
338 		    wh->i_fc[0], wh->i_fc[1]);
339 		vap->iv_stats.is_rx_badversion++;
340 		goto err;
341 	}
342 
343 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
344 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
345 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
346 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
347 		if (dir != IEEE80211_FC1_DIR_NODS)
348 			bssid = wh->i_addr1;
349 		else if (type == IEEE80211_FC0_TYPE_CTL)
350 			bssid = wh->i_addr1;
351 		else {
352 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
353 				IEEE80211_DISCARD_MAC(vap,
354 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
355 				    NULL, "too short (2): len %u",
356 				    m->m_pkthdr.len);
357 				vap->iv_stats.is_rx_tooshort++;
358 				goto out;
359 			}
360 			bssid = wh->i_addr3;
361 		}
362 		/*
363 		 * Validate the bssid.
364 		 */
365 		if (!IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
366 		    !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
367 			/* not interested in */
368 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
369 			    bssid, NULL, "%s", "not to bss");
370 			vap->iv_stats.is_rx_wrongbss++;
371 			goto out;
372 		}
373 		/*
374 		 * Data frame, cons up a node when it doesn't
375 		 * exist. This should probably done after an ACL check.
376 		 */
377 		if (type == IEEE80211_FC0_TYPE_DATA &&
378 		    ni == vap->iv_bss &&
379 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
380 			/*
381 			 * Beware of frames that come in too early; we
382 			 * can receive broadcast frames and creating sta
383 			 * entries will blow up because there is no bss
384 			 * channel yet.
385 			 */
386 			if (vap->iv_state != IEEE80211_S_RUN) {
387 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
388 				    wh, "data", "not in RUN state (%s)",
389 				    ieee80211_state_name[vap->iv_state]);
390 				vap->iv_stats.is_rx_badstate++;
391 				goto err;
392 			}
393 			/*
394 			 * Fake up a node for this newly
395 			 * discovered member of the IBSS.
396 			 */
397 			ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
398 			if (ni == NULL) {
399 				/* NB: stat kept for alloc failure */
400 				goto err;
401 			}
402 		}
403 		IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
404 		ni->ni_noise = nf;
405 		if (HAS_SEQ(type)) {
406 			uint8_t tid = ieee80211_gettid(wh);
407 			if (IEEE80211_QOS_HAS_SEQ(wh) &&
408 			    TID_TO_WME_AC(tid) >= WME_AC_VI)
409 				ic->ic_wme.wme_hipri_traffic++;
410 			rxseq = le16toh(*(uint16_t *)wh->i_seq);
411 			if ((ni->ni_flags & IEEE80211_NODE_HT) == 0 &&
412 			    (wh->i_fc[1] & IEEE80211_FC1_RETRY) &&
413 			    SEQ_LEQ(rxseq, ni->ni_rxseqs[tid])) {
414 				/* duplicate, discard */
415 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
416 				    bssid, "duplicate",
417 				    "seqno <%u,%u> fragno <%u,%u> tid %u",
418 				    rxseq >> IEEE80211_SEQ_SEQ_SHIFT,
419 				    ni->ni_rxseqs[tid] >>
420 					IEEE80211_SEQ_SEQ_SHIFT,
421 				    rxseq & IEEE80211_SEQ_FRAG_MASK,
422 				    ni->ni_rxseqs[tid] &
423 					IEEE80211_SEQ_FRAG_MASK,
424 				    tid);
425 				vap->iv_stats.is_rx_dup++;
426 				IEEE80211_NODE_STAT(ni, rx_dup);
427 				goto out;
428 			}
429 			ni->ni_rxseqs[tid] = rxseq;
430 		}
431 	}
432 
433 	switch (type) {
434 	case IEEE80211_FC0_TYPE_DATA:
435 		hdrspace = ieee80211_hdrspace(ic, wh);
436 		if (m->m_len < hdrspace &&
437 		    (m = m_pullup(m, hdrspace)) == NULL) {
438 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
439 			    ni->ni_macaddr, NULL,
440 			    "data too short: expecting %u", hdrspace);
441 			vap->iv_stats.is_rx_tooshort++;
442 			goto out;		/* XXX */
443 		}
444 		if (dir != IEEE80211_FC1_DIR_NODS) {
445 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
446 			    wh, "data", "incorrect dir 0x%x", dir);
447 			vap->iv_stats.is_rx_wrongdir++;
448 			goto out;
449 		}
450 		/* XXX no power-save support */
451 
452 		/*
453 		 * Handle A-MPDU re-ordering.  If the frame is to be
454 		 * processed directly then ieee80211_ampdu_reorder
455 		 * will return 0; otherwise it has consumed the mbuf
456 		 * and we should do nothing more with it.
457 		 */
458 		if ((m->m_flags & M_AMPDU) &&
459 		    ieee80211_ampdu_reorder(ni, m) != 0) {
460 			m = NULL;
461 			goto out;
462 		}
463 	resubmit_ampdu:
464 
465 		/*
466 		 * Handle privacy requirements.  Note that we
467 		 * must not be preempted from here until after
468 		 * we (potentially) call ieee80211_crypto_demic;
469 		 * otherwise we may violate assumptions in the
470 		 * crypto cipher modules used to do delayed update
471 		 * of replay sequence numbers.
472 		 */
473 		if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
474 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
475 				/*
476 				 * Discard encrypted frames when privacy is off.
477 				 */
478 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
479 				    wh, "WEP", "%s", "PRIVACY off");
480 				vap->iv_stats.is_rx_noprivacy++;
481 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
482 				goto out;
483 			}
484 			key = ieee80211_crypto_decap(ni, m, hdrspace);
485 			if (key == NULL) {
486 				/* NB: stats+msgs handled in crypto_decap */
487 				IEEE80211_NODE_STAT(ni, rx_wepfail);
488 				goto out;
489 			}
490 			wh = mtod(m, struct ieee80211_frame *);
491 			wh->i_fc[1] &= ~IEEE80211_FC1_WEP;
492 		} else {
493 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
494 			key = NULL;
495 		}
496 
497 		/*
498 		 * Save QoS bits for use below--before we strip the header.
499 		 */
500 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
501 			qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
502 			    ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
503 			    ((struct ieee80211_qosframe *)wh)->i_qos[0];
504 		} else
505 			qos = 0;
506 
507 		/*
508 		 * Next up, any fragmentation.
509 		 */
510 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
511 			m = ieee80211_defrag(ni, m, hdrspace);
512 			if (m == NULL) {
513 				/* Fragment dropped or frame not complete yet */
514 				goto out;
515 			}
516 		}
517 		wh = NULL;		/* no longer valid, catch any uses */
518 
519 		/*
520 		 * Next strip any MSDU crypto bits.
521 		 */
522 		if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
523 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
524 			    ni->ni_macaddr, "data", "%s", "demic error");
525 			vap->iv_stats.is_rx_demicfail++;
526 			IEEE80211_NODE_STAT(ni, rx_demicfail);
527 			goto out;
528 		}
529 
530 		/* copy to listener after decrypt */
531 		if (ieee80211_radiotap_active_vap(vap))
532 			ieee80211_radiotap_rx(vap, m);
533 		need_tap = 0;
534 
535 		/*
536 		 * Finally, strip the 802.11 header.
537 		 */
538 		m = ieee80211_decap(vap, m, hdrspace);
539 		if (m == NULL) {
540 			/* XXX mask bit to check for both */
541 			/* don't count Null data frames as errors */
542 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
543 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
544 				goto out;
545 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
546 			    ni->ni_macaddr, "data", "%s", "decap error");
547 			vap->iv_stats.is_rx_decap++;
548 			IEEE80211_NODE_STAT(ni, rx_decap);
549 			goto err;
550 		}
551 		eh = mtod(m, struct ether_header *);
552 		if (!ieee80211_node_is_authorized(ni)) {
553 			/*
554 			 * Deny any non-PAE frames received prior to
555 			 * authorization.  For open/shared-key
556 			 * authentication the port is mark authorized
557 			 * after authentication completes.  For 802.1x
558 			 * the port is not marked authorized by the
559 			 * authenticator until the handshake has completed.
560 			 */
561 			if (eh->ether_type != htons(ETHERTYPE_PAE)) {
562 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
563 				    eh->ether_shost, "data",
564 				    "unauthorized port: ether type 0x%x len %u",
565 				    eh->ether_type, m->m_pkthdr.len);
566 				vap->iv_stats.is_rx_unauth++;
567 				IEEE80211_NODE_STAT(ni, rx_unauth);
568 				goto err;
569 			}
570 		} else {
571 			/*
572 			 * When denying unencrypted frames, discard
573 			 * any non-PAE frames received without encryption.
574 			 */
575 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
576 			    (key == NULL && (m->m_flags & M_WEP) == 0) &&
577 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
578 				/*
579 				 * Drop unencrypted frames.
580 				 */
581 				vap->iv_stats.is_rx_unencrypted++;
582 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
583 				goto out;
584 			}
585 		}
586 		/* XXX require HT? */
587 		if (qos & IEEE80211_QOS_AMSDU) {
588 			m = ieee80211_decap_amsdu(ni, m);
589 			if (m == NULL)
590 				return IEEE80211_FC0_TYPE_DATA;
591 		} else {
592 #ifdef IEEE80211_SUPPORT_SUPERG
593 			m = ieee80211_decap_fastframe(vap, ni, m);
594 			if (m == NULL)
595 				return IEEE80211_FC0_TYPE_DATA;
596 #endif
597 		}
598 		if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
599 			ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
600 		else
601 			ieee80211_deliver_data(vap, ni, m);
602 		return IEEE80211_FC0_TYPE_DATA;
603 
604 	case IEEE80211_FC0_TYPE_MGT:
605 		vap->iv_stats.is_rx_mgmt++;
606 		IEEE80211_NODE_STAT(ni, rx_mgmt);
607 		if (dir != IEEE80211_FC1_DIR_NODS) {
608 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
609 			    wh, "data", "incorrect dir 0x%x", dir);
610 			vap->iv_stats.is_rx_wrongdir++;
611 			goto err;
612 		}
613 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
614 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
615 			    ni->ni_macaddr, "mgt", "too short: len %u",
616 			    m->m_pkthdr.len);
617 			vap->iv_stats.is_rx_tooshort++;
618 			goto out;
619 		}
620 #ifdef IEEE80211_DEBUG
621 		if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
622 		    ieee80211_msg_dumppkts(vap)) {
623 			if_printf(ifp, "received %s from %6D rssi %d\n",
624 			    ieee80211_mgt_subtype_name[subtype >>
625 				IEEE80211_FC0_SUBTYPE_SHIFT],
626 			    wh->i_addr2, ":", rssi);
627 		}
628 #endif
629 		if (wh->i_fc[1] & IEEE80211_FC1_WEP) {
630 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
631 			    wh, NULL, "%s", "WEP set but not permitted");
632 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
633 			goto out;
634 		}
635 		vap->iv_recv_mgmt(ni, m, subtype, rssi, nf);
636 		goto out;
637 
638 	case IEEE80211_FC0_TYPE_CTL:
639 		vap->iv_stats.is_rx_ctl++;
640 		IEEE80211_NODE_STAT(ni, rx_ctrl);
641 		vap->iv_recv_ctl(ni, m, subtype);
642 		goto out;
643 
644 	default:
645 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
646 		    wh, "bad", "frame type 0x%x", type);
647 		/* should not come here */
648 		break;
649 	}
650 err:
651 	ifp->if_ierrors++;
652 out:
653 	if (m != NULL) {
654 		if (need_tap && ieee80211_radiotap_active_vap(vap))
655 			ieee80211_radiotap_rx(vap, m);
656 		m_freem(m);
657 	}
658 	return type;
659 #undef SEQ_LEQ
660 }
661 
662 static int
663 is11bclient(const uint8_t *rates, const uint8_t *xrates)
664 {
665 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
666 	int i;
667 
668 	/* NB: the 11b clients we care about will not have xrates */
669 	if (xrates != NULL || rates == NULL)
670 		return 0;
671 	for (i = 0; i < rates[1]; i++) {
672 		int r = rates[2+i] & IEEE80211_RATE_VAL;
673 		if (r > 2*11 || ((1<<r) & brates) == 0)
674 			return 0;
675 	}
676 	return 1;
677 }
678 
679 static void
680 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
681 	int subtype, int rssi, int nf)
682 {
683 	struct ieee80211vap *vap = ni->ni_vap;
684 	struct ieee80211com *ic = ni->ni_ic;
685 	struct ieee80211_frame *wh;
686 	uint8_t *frm, *efrm, *sfrm;
687 	uint8_t *ssid, *rates, *xrates;
688 
689 	wh = mtod(m0, struct ieee80211_frame *);
690 	frm = (uint8_t *)&wh[1];
691 	efrm = mtod(m0, uint8_t *) + m0->m_len;
692 	switch (subtype) {
693 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
694 	case IEEE80211_FC0_SUBTYPE_BEACON: {
695 		struct ieee80211_scanparams scan;
696 		/*
697 		 * We process beacon/probe response
698 		 * frames to discover neighbors.
699 		 */
700 		if (ieee80211_parse_beacon(ni, m0, &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, &scan, wh, subtype, rssi, nf);
727 			return;
728 		}
729 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
730 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
731 				/*
732 				 * Create a new entry in the neighbor table.
733 				 */
734 				ni = ieee80211_add_neighbor(vap, wh, &scan);
735 			} else if (ni->ni_capinfo == 0) {
736 				/*
737 				 * Update faked node created on transmit.
738 				 * Note this also updates the tsf.
739 				 */
740 				ieee80211_init_neighbor(ni, wh, &scan);
741 			} else {
742 				/*
743 				 * Record tsf for potential resync.
744 				 */
745 				memcpy(ni->ni_tstamp.data, scan.tstamp,
746 					sizeof(ni->ni_tstamp));
747 			}
748 			if (ni != NULL) {
749 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
750 				ni->ni_noise = nf;
751 			}
752 		}
753 		break;
754 	}
755 
756 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
757 		if (vap->iv_state != IEEE80211_S_RUN) {
758 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
759 			    wh, NULL, "wrong state %s",
760 			    ieee80211_state_name[vap->iv_state]);
761 			vap->iv_stats.is_rx_mgtdiscard++;
762 			return;
763 		}
764 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
765 			/* frame must be directed */
766 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
767 			    wh, NULL, "%s", "not unicast");
768 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
769 			return;
770 		}
771 
772 		/*
773 		 * prreq frame format
774 		 *	[tlv] ssid
775 		 *	[tlv] supported rates
776 		 *	[tlv] extended supported rates
777 		 */
778 		ssid = rates = xrates = NULL;
779 		sfrm = frm;
780 		while (efrm - frm > 1) {
781 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
782 			switch (*frm) {
783 			case IEEE80211_ELEMID_SSID:
784 				ssid = frm;
785 				break;
786 			case IEEE80211_ELEMID_RATES:
787 				rates = frm;
788 				break;
789 			case IEEE80211_ELEMID_XRATES:
790 				xrates = frm;
791 				break;
792 			}
793 			frm += frm[1] + 2;
794 		}
795 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
796 		if (xrates != NULL)
797 			IEEE80211_VERIFY_ELEMENT(xrates,
798 				IEEE80211_RATE_MAXSIZE - rates[1], return);
799 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
800 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
801 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
802 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
803 			    wh, NULL,
804 			    "%s", "no ssid with ssid suppression enabled");
805 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
806 			return;
807 		}
808 
809 		/* XXX find a better class or define it's own */
810 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
811 		    "%s", "recv probe req");
812 		/*
813 		 * Some legacy 11b clients cannot hack a complete
814 		 * probe response frame.  When the request includes
815 		 * only a bare-bones rate set, communicate this to
816 		 * the transmit side.
817 		 */
818 		ieee80211_send_proberesp(vap, wh->i_addr2,
819 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
820 		break;
821 
822 	case IEEE80211_FC0_SUBTYPE_ACTION: {
823 		const struct ieee80211_action *ia;
824 
825 		if (vap->iv_state != IEEE80211_S_RUN) {
826 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
827 			    wh, NULL, "wrong state %s",
828 			    ieee80211_state_name[vap->iv_state]);
829 			vap->iv_stats.is_rx_mgtdiscard++;
830 			return;
831 		}
832 		/*
833 		 * action frame format:
834 		 *	[1] category
835 		 *	[1] action
836 		 *	[tlv] parameters
837 		 */
838 		IEEE80211_VERIFY_LENGTH(efrm - frm,
839 			sizeof(struct ieee80211_action), return);
840 		ia = (const struct ieee80211_action *) frm;
841 
842 		vap->iv_stats.is_rx_action++;
843 		IEEE80211_NODE_STAT(ni, rx_action);
844 
845 		/* verify frame payloads but defer processing */
846 		/* XXX maybe push this to method */
847 		switch (ia->ia_category) {
848 		case IEEE80211_ACTION_CAT_BA:
849 			switch (ia->ia_action) {
850 			case IEEE80211_ACTION_BA_ADDBA_REQUEST:
851 				IEEE80211_VERIFY_LENGTH(efrm - frm,
852 				    sizeof(struct ieee80211_action_ba_addbarequest),
853 				    return);
854 				break;
855 			case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
856 				IEEE80211_VERIFY_LENGTH(efrm - frm,
857 				    sizeof(struct ieee80211_action_ba_addbaresponse),
858 				    return);
859 				break;
860 			case IEEE80211_ACTION_BA_DELBA:
861 				IEEE80211_VERIFY_LENGTH(efrm - frm,
862 				    sizeof(struct ieee80211_action_ba_delba),
863 				    return);
864 				break;
865 			}
866 			break;
867 		case IEEE80211_ACTION_CAT_HT:
868 			switch (ia->ia_action) {
869 			case IEEE80211_ACTION_HT_TXCHWIDTH:
870 				IEEE80211_VERIFY_LENGTH(efrm - frm,
871 				    sizeof(struct ieee80211_action_ht_txchwidth),
872 				    return);
873 				break;
874 			}
875 			break;
876 		}
877 		ic->ic_recv_action(ni, wh, frm, efrm);
878 		break;
879 	}
880 
881 	case IEEE80211_FC0_SUBTYPE_AUTH:
882 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
883 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
884 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
885 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
886 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
887 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
888 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
889 		     wh, NULL, "%s", "not handled");
890 		vap->iv_stats.is_rx_mgtdiscard++;
891 		return;
892 
893 	default:
894 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
895 		     wh, "mgt", "subtype 0x%x not handled", subtype);
896 		vap->iv_stats.is_rx_badsubtype++;
897 		break;
898 	}
899 }
900 #undef IEEE80211_VERIFY_LENGTH
901 #undef IEEE80211_VERIFY_ELEMENT
902 
903 static void
904 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
905 	int subtype, int rssi, int nf)
906 {
907 	struct ieee80211vap *vap = ni->ni_vap;
908 	struct ieee80211com *ic = ni->ni_ic;
909 
910 	/*
911 	 * Process management frames when scanning; useful for doing
912 	 * a site-survey.
913 	 */
914 	if (ic->ic_flags & IEEE80211_F_SCAN)
915 		adhoc_recv_mgmt(ni, m0, subtype, rssi, nf);
916 	else
917 		vap->iv_stats.is_rx_mgtdiscard++;
918 }
919 
920 static void
921 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m0, int subtype)
922 {
923 }
924