1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  *
26  * $FreeBSD: head/sys/net80211/ieee80211_input.c 205986 2010-03-31 16:07:36Z rpaulo $
27  */
28 
29 #include "opt_wlan.h"
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/mbuf.h>
34 #include <sys/malloc.h>
35 #include <sys/endian.h>
36 #include <sys/kernel.h>
37 
38 #include <sys/socket.h>
39 
40 #include <net/ethernet.h>
41 #include <net/if.h>
42 #include <net/if_llc.h>
43 #include <net/if_media.h>
44 #include <net/route.h>
45 
46 #include <netproto/802_11/ieee80211_var.h>
47 #include <netproto/802_11/ieee80211_input.h>
48 #ifdef IEEE80211_SUPPORT_MESH
49 #include <netproto/802_11/ieee80211_mesh.h>
50 #endif
51 
52 #include <net/bpf.h>
53 
54 #ifdef INET
55 #include <netinet/in.h>
56 #endif
57 
58 int
59 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
60 {
61 	struct ieee80211vap *vap;
62 	int type = -1;
63 
64 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
65 
66 	/* XXX locking */
67 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
68 		struct ieee80211_node *ni;
69 		struct mbuf *mcopy;
70 
71 		/* NB: could check for IFF_UP but this is cheaper */
72 		if (vap->iv_state == IEEE80211_S_INIT)
73 			continue;
74 		/*
75 		 * WDS vap's only receive directed traffic from the
76 		 * station at the ``far end''.  That traffic should
77 		 * be passed through the AP vap the station is associated
78 		 * to--so don't spam them with mcast frames.
79 		 */
80 		if (vap->iv_opmode == IEEE80211_M_WDS)
81 			continue;
82 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
83 			/*
84 			 * Packet contents are changed by ieee80211_decap
85 			 * so do a deep copy of the packet.
86 			 */
87 			mcopy = m_dup(m, MB_DONTWAIT);
88 			if (mcopy == NULL) {
89 				/* XXX stat+msg */
90 				continue;
91 			}
92 		} else {
93 			mcopy = m;
94 			m = NULL;
95 		}
96 		ni = ieee80211_ref_node(vap->iv_bss);
97 		type = ieee80211_input(ni, mcopy, rssi, nf);
98 		ieee80211_free_node(ni);
99 	}
100 	if (m != NULL)			/* no vaps, reclaim mbuf */
101 		m_freem(m);
102 	return type;
103 }
104 
105 /*
106  * This function reassembles fragments.
107  *
108  * XXX should handle 3 concurrent reassemblies per-spec.
109  */
110 struct mbuf *
111 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
112 {
113 	struct ieee80211vap *vap = ni->ni_vap;
114 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
115 	struct ieee80211_frame *lwh;
116 	uint16_t rxseq;
117 	uint8_t fragno;
118 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
119 	struct mbuf *mfrag;
120 
121 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
122 
123 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
124 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
125 
126 	/* Quick way out, if there's nothing to defragment */
127 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
128 		return m;
129 
130 	/*
131 	 * Remove frag to insure it doesn't get reaped by timer.
132 	 */
133 	if (ni->ni_table == NULL) {
134 		/*
135 		 * Should never happen.  If the node is orphaned (not in
136 		 * the table) then input packets should not reach here.
137 		 * Otherwise, a concurrent request that yanks the table
138 		 * should be blocked by other interlocking and/or by first
139 		 * shutting the driver down.  Regardless, be defensive
140 		 * here and just bail
141 		 */
142 		/* XXX need msg+stat */
143 		m_freem(m);
144 		return NULL;
145 	}
146 	mfrag = ni->ni_rxfrag[0];
147 	ni->ni_rxfrag[0] = NULL;
148 
149 	/*
150 	 * Validate new fragment is in order and
151 	 * related to the previous ones.
152 	 */
153 	if (mfrag != NULL) {
154 		uint16_t last_rxseq;
155 
156 		lwh = mtod(mfrag, struct ieee80211_frame *);
157 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
158 		/* NB: check seq # and frag together */
159 		if (rxseq != last_rxseq+1 ||
160 		    !IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) ||
161 		    !IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
162 			/*
163 			 * Unrelated fragment or no space for it,
164 			 * clear current fragments.
165 			 */
166 			m_freem(mfrag);
167 			mfrag = NULL;
168 		}
169 	}
170 
171  	if (mfrag == NULL) {
172 		if (fragno != 0) {		/* !first fragment, discard */
173 			vap->iv_stats.is_rx_defrag++;
174 			IEEE80211_NODE_STAT(ni, rx_defrag);
175 			m_freem(m);
176 			return NULL;
177 		}
178 		mfrag = m;
179 	} else {				/* concatenate */
180 		m_adj(m, hdrspace);		/* strip header */
181 		m_cat(mfrag, m);
182 		/* NB: m_cat doesn't update the packet header */
183 		mfrag->m_pkthdr.len += m->m_pkthdr.len;
184 		/* track last seqnum and fragno */
185 		lwh = mtod(mfrag, struct ieee80211_frame *);
186 		*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
187 	}
188 	if (more_frag) {			/* more to come, save */
189 		ni->ni_rxfragstamp = ticks;
190 		ni->ni_rxfrag[0] = mfrag;
191 		mfrag = NULL;
192 	}
193 	return mfrag;
194 }
195 
196 void
197 ieee80211_deliver_data(struct ieee80211vap *vap,
198 	struct ieee80211_node *ni, struct mbuf *m)
199 {
200 	struct ether_header *eh = mtod(m, struct ether_header *);
201 	struct ifnet *ifp = vap->iv_ifp;
202 
203 	/* clear driver/net80211 flags before passing up */
204 	m->m_flags &= ~(M_80211_RX | M_MCAST | M_BCAST);
205 
206 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
207 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
208 	/*
209 	 * Do accounting.
210 	 */
211 	IFNET_STAT_INC(ifp, ipackets, 1);
212 	IEEE80211_NODE_STAT(ni, rx_data);
213 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
214 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
215 		m->m_flags |= M_MCAST;		/* XXX M_BCAST? */
216 		IEEE80211_NODE_STAT(ni, rx_mcast);
217 	} else
218 		IEEE80211_NODE_STAT(ni, rx_ucast);
219 	m->m_pkthdr.rcvif = ifp;
220 
221 	if (ni->ni_vlan != 0) {
222 		/* attach vlan tag */
223 		m->m_pkthdr.ether_vlantag = ni->ni_vlan;
224 		m->m_flags |= M_VLANTAG;
225 	}
226 	ifp->if_input(ifp, m);
227 }
228 
229 struct mbuf *
230 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
231 {
232 	struct ieee80211_qosframe_addr4 wh;
233 	struct ether_header *eh;
234 	struct llc *llc;
235 
236 	KASSERT(hdrlen <= sizeof(wh),
237 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
238 
239 	if (m->m_len < hdrlen + sizeof(*llc) &&
240 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
241 		vap->iv_stats.is_rx_tooshort++;
242 		/* XXX msg */
243 		return NULL;
244 	}
245 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
246 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
247 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
248 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
249 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
250 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
251 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
252 		llc = NULL;
253 	} else {
254 		m_adj(m, hdrlen - sizeof(*eh));
255 	}
256 	eh = mtod(m, struct ether_header *);
257 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
258 	case IEEE80211_FC1_DIR_NODS:
259 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
260 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
261 		break;
262 	case IEEE80211_FC1_DIR_TODS:
263 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
264 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
265 		break;
266 	case IEEE80211_FC1_DIR_FROMDS:
267 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
268 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
269 		break;
270 	case IEEE80211_FC1_DIR_DSTODS:
271 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
272 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
273 		break;
274 	}
275 #ifdef ALIGNED_POINTER
276 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
277 		m = ieee80211_realign(vap, m, sizeof(*eh));
278 		if (m == NULL)
279 			return NULL;
280 	}
281 #endif /* ALIGNED_POINTER */
282 	if (llc != NULL) {
283 		eh = mtod(m, struct ether_header *);
284 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
285 	}
286 	return m;
287 }
288 
289 /*
290  * Decap a frame encapsulated in a fast-frame/A-MSDU.
291  */
292 struct mbuf *
293 ieee80211_decap1(struct mbuf *m, int *framelen)
294 {
295 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
296 	struct ether_header *eh;
297 	struct llc *llc;
298 
299 	/*
300 	 * The frame has an 802.3 header followed by an 802.2
301 	 * LLC header.  The encapsulated frame length is in the
302 	 * first header type field; save that and overwrite it
303 	 * with the true type field found in the second.  Then
304 	 * copy the 802.3 header up to where it belongs and
305 	 * adjust the mbuf contents to remove the void.
306 	 */
307 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
308 		return NULL;
309 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
310 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
311 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
312 		  + sizeof(struct ether_header) - sizeof(struct llc);
313 	eh->ether_type = llc->llc_un.type_snap.ether_type;
314 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
315 		sizeof(struct ether_header));
316 	m_adj(m, sizeof(struct llc));
317 	return m;
318 #undef FF_LLC_SIZE
319 }
320 
321 /*
322  * Install received rate set information in the node's state block.
323  */
324 int
325 ieee80211_setup_rates(struct ieee80211_node *ni,
326 	const uint8_t *rates, const uint8_t *xrates, int flags)
327 {
328 	struct ieee80211vap *vap = ni->ni_vap;
329 	struct ieee80211_rateset *rs = &ni->ni_rates;
330 
331 	memset(rs, 0, sizeof(*rs));
332 	rs->rs_nrates = rates[1];
333 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
334 	if (xrates != NULL) {
335 		uint8_t nxrates;
336 		/*
337 		 * Tack on 11g extended supported rate element.
338 		 */
339 		nxrates = xrates[1];
340 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
341 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
342 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
343 			    "extended rate set too large; only using "
344 			    "%u of %u rates", nxrates, xrates[1]);
345 			vap->iv_stats.is_rx_rstoobig++;
346 		}
347 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
348 		rs->rs_nrates += nxrates;
349 	}
350 	return ieee80211_fix_rate(ni, rs, flags);
351 }
352 
353 /*
354  * Send a management frame error response to the specified
355  * station.  If ni is associated with the station then use
356  * it; otherwise allocate a temporary node suitable for
357  * transmitting the frame and then free the reference so
358  * it will go away as soon as the frame has been transmitted.
359  */
360 void
361 ieee80211_send_error(struct ieee80211_node *ni,
362 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
363 {
364 	struct ieee80211vap *vap = ni->ni_vap;
365 	int istmp;
366 
367 	if (ni == vap->iv_bss) {
368 		if (vap->iv_state != IEEE80211_S_RUN) {
369 			/*
370 			 * XXX hack until we get rid of this routine.
371 			 * We can be called prior to the vap reaching
372 			 * run state under certain conditions in which
373 			 * case iv_bss->ni_chan will not be setup.
374 			 * Check for this explicitly and and just ignore
375 			 * the request.
376 			 */
377 			return;
378 		}
379 		ni = ieee80211_tmp_node(vap, mac);
380 		if (ni == NULL) {
381 			/* XXX msg */
382 			return;
383 		}
384 		istmp = 1;
385 	} else
386 		istmp = 0;
387 	IEEE80211_SEND_MGMT(ni, subtype, arg);
388 	if (istmp)
389 		ieee80211_free_node(ni);
390 }
391 
392 int
393 ieee80211_alloc_challenge(struct ieee80211_node *ni)
394 {
395 	if (ni->ni_challenge == NULL)
396 		ni->ni_challenge = (uint32_t *) kmalloc(IEEE80211_CHALLENGE_LEN,
397 		    M_80211_NODE, M_INTWAIT);
398 	if (ni->ni_challenge == NULL) {
399 		IEEE80211_NOTE(ni->ni_vap,
400 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
401 		    "%s", "shared key challenge alloc failed");
402 		/* XXX statistic */
403 	}
404 	return (ni->ni_challenge != NULL);
405 }
406 
407 /*
408  * Parse a Beacon or ProbeResponse frame and return the
409  * useful information in an ieee80211_scanparams structure.
410  * Status is set to 0 if no problems were found; otherwise
411  * a bitmask of IEEE80211_BPARSE_* items is returned that
412  * describes the problems detected.
413  */
414 int
415 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
416 	struct ieee80211_scanparams *scan)
417 {
418 	struct ieee80211vap *vap = ni->ni_vap;
419 	struct ieee80211com *ic = ni->ni_ic;
420 	struct ieee80211_frame *wh;
421 	uint8_t *frm, *efrm;
422 
423 	wh = mtod(m, struct ieee80211_frame *);
424 	frm = (uint8_t *)&wh[1];
425 	efrm = mtod(m, uint8_t *) + m->m_len;
426 	scan->status = 0;
427 	/*
428 	 * beacon/probe response frame format
429 	 *	[8] time stamp
430 	 *	[2] beacon interval
431 	 *	[2] capability information
432 	 *	[tlv] ssid
433 	 *	[tlv] supported rates
434 	 *	[tlv] country information
435 	 *	[tlv] channel switch announcement (CSA)
436 	 *	[tlv] parameter set (FH/DS)
437 	 *	[tlv] erp information
438 	 *	[tlv] extended supported rates
439 	 *	[tlv] WME
440 	 *	[tlv] WPA or RSN
441 	 *	[tlv] HT capabilities
442 	 *	[tlv] HT information
443 	 *	[tlv] Atheros capabilities
444 	 *	[tlv] Mesh ID
445 	 *	[tlv] Mesh Configuration
446 	 */
447 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
448 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
449 	memset(scan, 0, sizeof(*scan));
450 	scan->tstamp  = frm;				frm += 8;
451 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
452 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
453 	scan->bchan = ieee80211_chan2ieee(ic, ic->ic_curchan);
454 	scan->chan = scan->bchan;
455 	scan->ies = frm;
456 	scan->ies_len = efrm - frm;
457 
458 	while (efrm - frm > 1) {
459 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
460 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
461 		switch (*frm) {
462 		case IEEE80211_ELEMID_SSID:
463 			scan->ssid = frm;
464 			break;
465 		case IEEE80211_ELEMID_RATES:
466 			scan->rates = frm;
467 			break;
468 		case IEEE80211_ELEMID_COUNTRY:
469 			scan->country = frm;
470 			break;
471 		case IEEE80211_ELEMID_CSA:
472 			scan->csa = frm;
473 			break;
474 		case IEEE80211_ELEMID_FHPARMS:
475 			if (ic->ic_phytype == IEEE80211_T_FH) {
476 				scan->fhdwell = LE_READ_2(&frm[2]);
477 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
478 				scan->fhindex = frm[6];
479 			}
480 			break;
481 		case IEEE80211_ELEMID_DSPARMS:
482 			/*
483 			 * XXX hack this since depending on phytype
484 			 * is problematic for multi-mode devices.
485 			 */
486 			if (ic->ic_phytype != IEEE80211_T_FH)
487 				scan->chan = frm[2];
488 			break;
489 		case IEEE80211_ELEMID_TIM:
490 			/* XXX ATIM? */
491 			scan->tim = frm;
492 			scan->timoff = frm - mtod(m, uint8_t *);
493 			break;
494 		case IEEE80211_ELEMID_IBSSPARMS:
495 		case IEEE80211_ELEMID_CFPARMS:
496 		case IEEE80211_ELEMID_PWRCNSTR:
497 			/* NB: avoid debugging complaints */
498 			break;
499 		case IEEE80211_ELEMID_XRATES:
500 			scan->xrates = frm;
501 			break;
502 		case IEEE80211_ELEMID_ERP:
503 			if (frm[1] != 1) {
504 				IEEE80211_DISCARD_IE(vap,
505 				    IEEE80211_MSG_ELEMID, wh, "ERP",
506 				    "bad len %u", frm[1]);
507 				vap->iv_stats.is_rx_elem_toobig++;
508 				break;
509 			}
510 			scan->erp = frm[2] | 0x100;
511 			break;
512 		case IEEE80211_ELEMID_HTCAP:
513 			scan->htcap = frm;
514 			break;
515 		case IEEE80211_ELEMID_RSN:
516 			scan->rsn = frm;
517 			break;
518 		case IEEE80211_ELEMID_HTINFO:
519 			scan->htinfo = frm;
520 			break;
521 #ifdef IEEE80211_SUPPORT_MESH
522 		case IEEE80211_ELEMID_MESHID:
523 			scan->meshid = frm;
524 			break;
525 		case IEEE80211_ELEMID_MESHCONF:
526 			scan->meshconf = frm;
527 			break;
528 #endif
529 		case IEEE80211_ELEMID_VENDOR:
530 			if (iswpaoui(frm))
531 				scan->wpa = frm;
532 			else if (iswmeparam(frm) || iswmeinfo(frm))
533 				scan->wme = frm;
534 #ifdef IEEE80211_SUPPORT_SUPERG
535 			else if (isatherosoui(frm))
536 				scan->ath = frm;
537 #endif
538 #ifdef IEEE80211_SUPPORT_TDMA
539 			else if (istdmaoui(frm))
540 				scan->tdma = frm;
541 #endif
542 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
543 				/*
544 				 * Accept pre-draft HT ie's if the
545 				 * standard ones have not been seen.
546 				 */
547 				if (ishtcapoui(frm)) {
548 					if (scan->htcap == NULL)
549 						scan->htcap = frm;
550 				} else if (ishtinfooui(frm)) {
551 					if (scan->htinfo == NULL)
552 						scan->htcap = frm;
553 				}
554 			}
555 			break;
556 		default:
557 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
558 			    wh, "unhandled",
559 			    "id %u, len %u", *frm, frm[1]);
560 			vap->iv_stats.is_rx_elem_unknown++;
561 			break;
562 		}
563 		frm += frm[1] + 2;
564 	}
565 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
566 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
567 	if (scan->rates != NULL && scan->xrates != NULL) {
568 		/*
569 		 * NB: don't process XRATES if RATES is missing.  This
570 		 * avoids a potential null ptr deref and should be ok
571 		 * as the return code will already note RATES is missing
572 		 * (so callers shouldn't otherwise process the frame).
573 		 */
574 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
575 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
576 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
577 	}
578 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
579 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
580 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
581 		/*
582 		 * Frame was received on a channel different from the
583 		 * one indicated in the DS params element id;
584 		 * silently discard it.
585 		 *
586 		 * NB: this can happen due to signal leakage.
587 		 *     But we should take it for FH phy because
588 		 *     the rssi value should be correct even for
589 		 *     different hop pattern in FH.
590 		 */
591 		IEEE80211_DISCARD(vap,
592 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
593 		    wh, NULL, "for off-channel %u", scan->chan);
594 		vap->iv_stats.is_rx_chanmismatch++;
595 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
596 	}
597 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
598 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
599 		IEEE80211_DISCARD(vap,
600 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
601 		    wh, NULL, "bogus beacon interval %u", scan->bintval);
602 		vap->iv_stats.is_rx_badbintval++;
603 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
604 	}
605 	if (scan->country != NULL) {
606 		/*
607 		 * Validate we have at least enough data to extract
608 		 * the country code.  Not sure if we should return an
609 		 * error instead of discarding the IE; consider this
610 		 * being lenient as we don't depend on the data for
611 		 * correct operation.
612 		 */
613 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
614 		    scan->country = NULL);
615 	}
616 	if (scan->csa != NULL) {
617 		/*
618 		 * Validate Channel Switch Announcement; this must
619 		 * be the correct length or we toss the frame.
620 		 */
621 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
622 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
623 	}
624 	/*
625 	 * Process HT ie's.  This is complicated by our
626 	 * accepting both the standard ie's and the pre-draft
627 	 * vendor OUI ie's that some vendors still use/require.
628 	 */
629 	if (scan->htcap != NULL) {
630 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
631 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
632 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
633 			 sizeof(struct ieee80211_ie_htcap)-2,
634 		     scan->htcap = NULL);
635 	}
636 	if (scan->htinfo != NULL) {
637 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
638 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
639 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
640 			 sizeof(struct ieee80211_ie_htinfo)-2,
641 		     scan->htinfo = NULL);
642 	}
643 	return scan->status;
644 }
645 
646 /*
647  * Parse an Action frame.  Return 0 on success, non-zero on failure.
648  */
649 int
650 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
651 {
652 	struct ieee80211vap *vap = ni->ni_vap;
653 	const struct ieee80211_action *ia;
654 	struct ieee80211_frame *wh;
655 	uint8_t *frm, *efrm;
656 
657 	/*
658 	 * action frame format:
659 	 *	[1] category
660 	 *	[1] action
661 	 *	[tlv] parameters
662 	 */
663 	wh = mtod(m, struct ieee80211_frame *);
664 	frm = (u_int8_t *)&wh[1];
665 	efrm = mtod(m, u_int8_t *) + m->m_len;
666 	IEEE80211_VERIFY_LENGTH(efrm - frm,
667 		sizeof(struct ieee80211_action), return EINVAL);
668 	ia = (const struct ieee80211_action *) frm;
669 
670 	vap->iv_stats.is_rx_action++;
671 	IEEE80211_NODE_STAT(ni, rx_action);
672 
673 	/* verify frame payloads but defer processing */
674 	/* XXX maybe push this to method */
675 	switch (ia->ia_category) {
676 	case IEEE80211_ACTION_CAT_BA:
677 		switch (ia->ia_action) {
678 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
679 			IEEE80211_VERIFY_LENGTH(efrm - frm,
680 			    sizeof(struct ieee80211_action_ba_addbarequest),
681 			    return EINVAL);
682 			break;
683 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
684 			IEEE80211_VERIFY_LENGTH(efrm - frm,
685 			    sizeof(struct ieee80211_action_ba_addbaresponse),
686 			    return EINVAL);
687 			break;
688 		case IEEE80211_ACTION_BA_DELBA:
689 			IEEE80211_VERIFY_LENGTH(efrm - frm,
690 			    sizeof(struct ieee80211_action_ba_delba),
691 			    return EINVAL);
692 			break;
693 		}
694 		break;
695 	case IEEE80211_ACTION_CAT_HT:
696 		switch (ia->ia_action) {
697 		case IEEE80211_ACTION_HT_TXCHWIDTH:
698 			IEEE80211_VERIFY_LENGTH(efrm - frm,
699 			    sizeof(struct ieee80211_action_ht_txchwidth),
700 			    return EINVAL);
701 			break;
702 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
703 			IEEE80211_VERIFY_LENGTH(efrm - frm,
704 			    sizeof(struct ieee80211_action_ht_mimopowersave),
705 			    return EINVAL);
706 			break;
707 		}
708 		break;
709 	}
710 	return 0;
711 }
712 
713 /*
714  * Modules may be compiled with debugging even if wlan isn't
715  */
716 /*#ifdef IEEE80211_DEBUG*/
717 #if 1
718 /*
719  * Debugging support.
720  */
721 void
722 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
723 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
724 {
725 	char ethstr[ETHER_ADDRSTRLEN + 1];
726 
727 	kprintf("[%s] discard %s frame, ssid mismatch: ",
728 	    kether_ntoa(mac, ethstr), tag);
729 	ieee80211_print_essid(ssid + 2, ssid[1]);
730 	kprintf("\n");
731 }
732 
733 /*
734  * Return the bssid of a frame.
735  */
736 static const uint8_t *
737 ieee80211_getbssid(const struct ieee80211vap *vap, const struct ieee80211_frame *wh)
738 {
739 	if (vap->iv_opmode == IEEE80211_M_STA)
740 		return wh->i_addr2;
741 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
742 		return wh->i_addr1;
743 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
744 		return wh->i_addr1;
745 	return wh->i_addr3;
746 }
747 
748 #include <machine/stdarg.h>
749 
750 void
751 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
752 {
753 	char buf[128];		/* XXX */
754 	__va_list ap;
755 
756 	__va_start(ap, fmt);
757 	kvsnprintf(buf, sizeof(buf), fmt, ap);
758 	__va_end(ap);
759 
760 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
761 }
762 
763 void
764 ieee80211_note_frame(const struct ieee80211vap *vap,
765 	const struct ieee80211_frame *wh,
766 	const char *fmt, ...)
767 {
768 	char buf[128];		/* XXX */
769 	__va_list ap;
770 	char ethstr[ETHER_ADDRSTRLEN + 1];
771 
772 	__va_start(ap, fmt);
773 	kvsnprintf(buf, sizeof(buf), fmt, ap);
774 	__va_end(ap);
775 	if_printf(vap->iv_ifp, "[%s] %s\n",
776 	    kether_ntoa(ieee80211_getbssid(vap, wh), ethstr), buf);
777 }
778 
779 void
780 ieee80211_note_mac(const struct ieee80211vap *vap,
781 	const uint8_t mac[IEEE80211_ADDR_LEN],
782 	const char *fmt, ...)
783 {
784 	char buf[128];		/* XXX */
785 	__va_list ap;
786 	char ethstr[ETHER_ADDRSTRLEN + 1];
787 
788 	__va_start(ap, fmt);
789 	kvsnprintf(buf, sizeof(buf), fmt, ap);
790 	__va_end(ap);
791 	if_printf(vap->iv_ifp, "[%s] %s\n", kether_ntoa(mac, ethstr), buf);
792 }
793 
794 void
795 ieee80211_discard_frame(const struct ieee80211vap *vap,
796 	const struct ieee80211_frame *wh,
797 	const char *type, const char *fmt, ...)
798 {
799 	__va_list ap;
800 	char ethstr[ETHER_ADDRSTRLEN + 1];
801 
802 	if_printf(vap->iv_ifp, "[%s] discard ",
803 	    kether_ntoa(ieee80211_getbssid(vap, wh), ethstr));
804 	if (type == NULL) {
805 		kprintf("%s frame, ", ieee80211_mgt_subtype_name[
806 			(wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) >>
807 			IEEE80211_FC0_SUBTYPE_SHIFT]);
808 	} else
809 		kprintf("%s frame, ", type);
810 	__va_start(ap, fmt);
811 	kvprintf(fmt, ap);
812 	__va_end(ap);
813 	kprintf("\n");
814 }
815 
816 void
817 ieee80211_discard_ie(const struct ieee80211vap *vap,
818 	const struct ieee80211_frame *wh,
819 	const char *type, const char *fmt, ...)
820 {
821 	__va_list ap;
822 	char ethstr[ETHER_ADDRSTRLEN + 1];
823 
824 	if_printf(vap->iv_ifp, "[%s] discard ",
825 	    kether_ntoa(ieee80211_getbssid(vap, wh), ethstr));
826 	if (type != NULL)
827 		kprintf("%s information element, ", type);
828 	else
829 		kprintf("information element, ");
830 	__va_start(ap, fmt);
831 	kvprintf(fmt, ap);
832 	__va_end(ap);
833 	kprintf("\n");
834 }
835 
836 void
837 ieee80211_discard_mac(const struct ieee80211vap *vap,
838 	const uint8_t mac[IEEE80211_ADDR_LEN],
839 	const char *type, const char *fmt, ...)
840 {
841 	__va_list ap;
842 	char ethstr[ETHER_ADDRSTRLEN + 1];
843 
844 	if_printf(vap->iv_ifp, "[%s] discard ", kether_ntoa(mac, ethstr));
845 	if (type != NULL)
846 		kprintf("%s frame, ", type);
847 	else
848 		kprintf("frame, ");
849 	__va_start(ap, fmt);
850 	kvprintf(fmt, ap);
851 	__va_end(ap);
852 	kprintf("\n");
853 }
854 #endif /* IEEE80211_DEBUG */
855