xref: /freebsd/sys/net80211/ieee80211_input.c (revision 3fc9e2c36555140de248a0b4def91bbfa44d7c2c)
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 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_wlan.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/mbuf.h>
35 #include <sys/malloc.h>
36 #include <sys/endian.h>
37 #include <sys/kernel.h>
38 
39 #include <sys/socket.h>
40 
41 #include <net/ethernet.h>
42 #include <net/if.h>
43 #include <net/if_llc.h>
44 #include <net/if_media.h>
45 #include <net/if_vlan_var.h>
46 
47 #include <net80211/ieee80211_var.h>
48 #include <net80211/ieee80211_input.h>
49 #ifdef IEEE80211_SUPPORT_MESH
50 #include <net80211/ieee80211_mesh.h>
51 #endif
52 
53 #include <net/bpf.h>
54 
55 #ifdef INET
56 #include <netinet/in.h>
57 #include <net/ethernet.h>
58 #endif
59 
60 static void
61 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
62 {
63 	int i;
64 
65 	/* Verify the required MIMO bits are set */
66 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
67 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
68 		return;
69 
70 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
71 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
72 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
73 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
74 	}
75 
76 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
77 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
78 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
79 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
80 	}
81 	ni->ni_mimo_chains = rx->c_chain;
82 }
83 
84 int
85 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
86     struct ieee80211_rx_stats *rx)
87 {
88 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
89 	ieee80211_process_mimo(ni, rx);
90 	return ieee80211_input(ni, m, rx->rssi, rx->nf);
91 }
92 
93 int
94 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
95 {
96 	struct ieee80211_rx_stats rx;
97 
98 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
99 	rx.nf = nf;
100 	rx.rssi = rssi;
101 	return ieee80211_input_mimo_all(ic, m, &rx);
102 }
103 
104 int
105 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
106     struct ieee80211_rx_stats *rx)
107 {
108 	struct ieee80211vap *vap;
109 	int type = -1;
110 
111 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
112 
113 	/* XXX locking */
114 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
115 		struct ieee80211_node *ni;
116 		struct mbuf *mcopy;
117 
118 		/* NB: could check for IFF_UP but this is cheaper */
119 		if (vap->iv_state == IEEE80211_S_INIT)
120 			continue;
121 		/*
122 		 * WDS vap's only receive directed traffic from the
123 		 * station at the ``far end''.  That traffic should
124 		 * be passed through the AP vap the station is associated
125 		 * to--so don't spam them with mcast frames.
126 		 */
127 		if (vap->iv_opmode == IEEE80211_M_WDS)
128 			continue;
129 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
130 			/*
131 			 * Packet contents are changed by ieee80211_decap
132 			 * so do a deep copy of the packet.
133 			 */
134 			mcopy = m_dup(m, M_NOWAIT);
135 			if (mcopy == NULL) {
136 				/* XXX stat+msg */
137 				continue;
138 			}
139 		} else {
140 			mcopy = m;
141 			m = NULL;
142 		}
143 		ni = ieee80211_ref_node(vap->iv_bss);
144 		type = ieee80211_input_mimo(ni, mcopy, rx);
145 		ieee80211_free_node(ni);
146 	}
147 	if (m != NULL)			/* no vaps, reclaim mbuf */
148 		m_freem(m);
149 	return type;
150 }
151 
152 /*
153  * This function reassembles fragments.
154  *
155  * XXX should handle 3 concurrent reassemblies per-spec.
156  */
157 struct mbuf *
158 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
159 {
160 	struct ieee80211vap *vap = ni->ni_vap;
161 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
162 	struct ieee80211_frame *lwh;
163 	uint16_t rxseq;
164 	uint8_t fragno;
165 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
166 	struct mbuf *mfrag;
167 
168 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
169 
170 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
171 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
172 
173 	/* Quick way out, if there's nothing to defragment */
174 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
175 		return m;
176 
177 	/*
178 	 * Remove frag to insure it doesn't get reaped by timer.
179 	 */
180 	if (ni->ni_table == NULL) {
181 		/*
182 		 * Should never happen.  If the node is orphaned (not in
183 		 * the table) then input packets should not reach here.
184 		 * Otherwise, a concurrent request that yanks the table
185 		 * should be blocked by other interlocking and/or by first
186 		 * shutting the driver down.  Regardless, be defensive
187 		 * here and just bail
188 		 */
189 		/* XXX need msg+stat */
190 		m_freem(m);
191 		return NULL;
192 	}
193 	IEEE80211_NODE_LOCK(ni->ni_table);
194 	mfrag = ni->ni_rxfrag[0];
195 	ni->ni_rxfrag[0] = NULL;
196 	IEEE80211_NODE_UNLOCK(ni->ni_table);
197 
198 	/*
199 	 * Validate new fragment is in order and
200 	 * related to the previous ones.
201 	 */
202 	if (mfrag != NULL) {
203 		uint16_t last_rxseq;
204 
205 		lwh = mtod(mfrag, struct ieee80211_frame *);
206 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
207 		/* NB: check seq # and frag together */
208 		if (rxseq != last_rxseq+1 ||
209 		    !IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) ||
210 		    !IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
211 			/*
212 			 * Unrelated fragment or no space for it,
213 			 * clear current fragments.
214 			 */
215 			m_freem(mfrag);
216 			mfrag = NULL;
217 		}
218 	}
219 
220  	if (mfrag == NULL) {
221 		if (fragno != 0) {		/* !first fragment, discard */
222 			vap->iv_stats.is_rx_defrag++;
223 			IEEE80211_NODE_STAT(ni, rx_defrag);
224 			m_freem(m);
225 			return NULL;
226 		}
227 		mfrag = m;
228 	} else {				/* concatenate */
229 		m_adj(m, hdrspace);		/* strip header */
230 		m_cat(mfrag, m);
231 		/* NB: m_cat doesn't update the packet header */
232 		mfrag->m_pkthdr.len += m->m_pkthdr.len;
233 		/* track last seqnum and fragno */
234 		lwh = mtod(mfrag, struct ieee80211_frame *);
235 		*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
236 	}
237 	if (more_frag) {			/* more to come, save */
238 		ni->ni_rxfragstamp = ticks;
239 		ni->ni_rxfrag[0] = mfrag;
240 		mfrag = NULL;
241 	}
242 	return mfrag;
243 }
244 
245 void
246 ieee80211_deliver_data(struct ieee80211vap *vap,
247 	struct ieee80211_node *ni, struct mbuf *m)
248 {
249 	struct ether_header *eh = mtod(m, struct ether_header *);
250 	struct ifnet *ifp = vap->iv_ifp;
251 
252 	/* clear driver/net80211 flags before passing up */
253 	m->m_flags &= ~(M_MCAST | M_BCAST);
254 #if __FreeBSD_version >= 1000046
255 	m_clrprotoflags(m);
256 #endif
257 
258 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
259 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
260 	/*
261 	 * Do accounting.
262 	 */
263 	ifp->if_ipackets++;
264 	IEEE80211_NODE_STAT(ni, rx_data);
265 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
266 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
267 		m->m_flags |= M_MCAST;		/* XXX M_BCAST? */
268 		IEEE80211_NODE_STAT(ni, rx_mcast);
269 	} else
270 		IEEE80211_NODE_STAT(ni, rx_ucast);
271 	m->m_pkthdr.rcvif = ifp;
272 
273 	if (ni->ni_vlan != 0) {
274 		/* attach vlan tag */
275 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
276 		m->m_flags |= M_VLANTAG;
277 	}
278 	ifp->if_input(ifp, m);
279 }
280 
281 struct mbuf *
282 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
283 {
284 	struct ieee80211_qosframe_addr4 wh;
285 	struct ether_header *eh;
286 	struct llc *llc;
287 
288 	KASSERT(hdrlen <= sizeof(wh),
289 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
290 
291 	if (m->m_len < hdrlen + sizeof(*llc) &&
292 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
293 		vap->iv_stats.is_rx_tooshort++;
294 		/* XXX msg */
295 		return NULL;
296 	}
297 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
298 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
299 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
300 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
301 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
302 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
303 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
304 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
305 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
306 		llc = NULL;
307 	} else {
308 		m_adj(m, hdrlen - sizeof(*eh));
309 	}
310 	eh = mtod(m, struct ether_header *);
311 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
312 	case IEEE80211_FC1_DIR_NODS:
313 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
314 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
315 		break;
316 	case IEEE80211_FC1_DIR_TODS:
317 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
318 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
319 		break;
320 	case IEEE80211_FC1_DIR_FROMDS:
321 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
322 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
323 		break;
324 	case IEEE80211_FC1_DIR_DSTODS:
325 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
326 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
327 		break;
328 	}
329 #ifndef __NO_STRICT_ALIGNMENT
330 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
331 		m = ieee80211_realign(vap, m, sizeof(*eh));
332 		if (m == NULL)
333 			return NULL;
334 	}
335 #endif /* !__NO_STRICT_ALIGNMENT */
336 	if (llc != NULL) {
337 		eh = mtod(m, struct ether_header *);
338 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
339 	}
340 	return m;
341 }
342 
343 /*
344  * Decap a frame encapsulated in a fast-frame/A-MSDU.
345  */
346 struct mbuf *
347 ieee80211_decap1(struct mbuf *m, int *framelen)
348 {
349 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
350 	struct ether_header *eh;
351 	struct llc *llc;
352 
353 	/*
354 	 * The frame has an 802.3 header followed by an 802.2
355 	 * LLC header.  The encapsulated frame length is in the
356 	 * first header type field; save that and overwrite it
357 	 * with the true type field found in the second.  Then
358 	 * copy the 802.3 header up to where it belongs and
359 	 * adjust the mbuf contents to remove the void.
360 	 */
361 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
362 		return NULL;
363 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
364 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
365 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
366 		  + sizeof(struct ether_header) - sizeof(struct llc);
367 	eh->ether_type = llc->llc_un.type_snap.ether_type;
368 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
369 		sizeof(struct ether_header));
370 	m_adj(m, sizeof(struct llc));
371 	return m;
372 #undef FF_LLC_SIZE
373 }
374 
375 /*
376  * Install received rate set information in the node's state block.
377  */
378 int
379 ieee80211_setup_rates(struct ieee80211_node *ni,
380 	const uint8_t *rates, const uint8_t *xrates, int flags)
381 {
382 	struct ieee80211vap *vap = ni->ni_vap;
383 	struct ieee80211_rateset *rs = &ni->ni_rates;
384 
385 	memset(rs, 0, sizeof(*rs));
386 	rs->rs_nrates = rates[1];
387 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
388 	if (xrates != NULL) {
389 		uint8_t nxrates;
390 		/*
391 		 * Tack on 11g extended supported rate element.
392 		 */
393 		nxrates = xrates[1];
394 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
395 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
396 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
397 			    "extended rate set too large; only using "
398 			    "%u of %u rates", nxrates, xrates[1]);
399 			vap->iv_stats.is_rx_rstoobig++;
400 		}
401 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
402 		rs->rs_nrates += nxrates;
403 	}
404 	return ieee80211_fix_rate(ni, rs, flags);
405 }
406 
407 /*
408  * Send a management frame error response to the specified
409  * station.  If ni is associated with the station then use
410  * it; otherwise allocate a temporary node suitable for
411  * transmitting the frame and then free the reference so
412  * it will go away as soon as the frame has been transmitted.
413  */
414 void
415 ieee80211_send_error(struct ieee80211_node *ni,
416 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
417 {
418 	struct ieee80211vap *vap = ni->ni_vap;
419 	int istmp;
420 
421 	if (ni == vap->iv_bss) {
422 		if (vap->iv_state != IEEE80211_S_RUN) {
423 			/*
424 			 * XXX hack until we get rid of this routine.
425 			 * We can be called prior to the vap reaching
426 			 * run state under certain conditions in which
427 			 * case iv_bss->ni_chan will not be setup.
428 			 * Check for this explicitly and and just ignore
429 			 * the request.
430 			 */
431 			return;
432 		}
433 		ni = ieee80211_tmp_node(vap, mac);
434 		if (ni == NULL) {
435 			/* XXX msg */
436 			return;
437 		}
438 		istmp = 1;
439 	} else
440 		istmp = 0;
441 	IEEE80211_SEND_MGMT(ni, subtype, arg);
442 	if (istmp)
443 		ieee80211_free_node(ni);
444 }
445 
446 int
447 ieee80211_alloc_challenge(struct ieee80211_node *ni)
448 {
449 	if (ni->ni_challenge == NULL)
450 		ni->ni_challenge = (uint32_t *) malloc(IEEE80211_CHALLENGE_LEN,
451 		    M_80211_NODE, M_NOWAIT);
452 	if (ni->ni_challenge == NULL) {
453 		IEEE80211_NOTE(ni->ni_vap,
454 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
455 		    "%s", "shared key challenge alloc failed");
456 		/* XXX statistic */
457 	}
458 	return (ni->ni_challenge != NULL);
459 }
460 
461 /*
462  * Parse a Beacon or ProbeResponse frame and return the
463  * useful information in an ieee80211_scanparams structure.
464  * Status is set to 0 if no problems were found; otherwise
465  * a bitmask of IEEE80211_BPARSE_* items is returned that
466  * describes the problems detected.
467  */
468 int
469 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
470 	struct ieee80211_scanparams *scan)
471 {
472 	struct ieee80211vap *vap = ni->ni_vap;
473 	struct ieee80211com *ic = ni->ni_ic;
474 	struct ieee80211_frame *wh;
475 	uint8_t *frm, *efrm;
476 
477 	wh = mtod(m, struct ieee80211_frame *);
478 	frm = (uint8_t *)&wh[1];
479 	efrm = mtod(m, uint8_t *) + m->m_len;
480 	scan->status = 0;
481 	/*
482 	 * beacon/probe response frame format
483 	 *	[8] time stamp
484 	 *	[2] beacon interval
485 	 *	[2] capability information
486 	 *	[tlv] ssid
487 	 *	[tlv] supported rates
488 	 *	[tlv] country information
489 	 *	[tlv] channel switch announcement (CSA)
490 	 *	[tlv] parameter set (FH/DS)
491 	 *	[tlv] erp information
492 	 *	[tlv] extended supported rates
493 	 *	[tlv] WME
494 	 *	[tlv] WPA or RSN
495 	 *	[tlv] HT capabilities
496 	 *	[tlv] HT information
497 	 *	[tlv] Atheros capabilities
498 	 *	[tlv] Mesh ID
499 	 *	[tlv] Mesh Configuration
500 	 */
501 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
502 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
503 	memset(scan, 0, sizeof(*scan));
504 	scan->tstamp  = frm;				frm += 8;
505 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
506 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
507 	scan->bchan = ieee80211_chan2ieee(ic, ic->ic_curchan);
508 	scan->chan = scan->bchan;
509 	scan->ies = frm;
510 	scan->ies_len = efrm - frm;
511 
512 	while (efrm - frm > 1) {
513 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
514 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
515 		switch (*frm) {
516 		case IEEE80211_ELEMID_SSID:
517 			scan->ssid = frm;
518 			break;
519 		case IEEE80211_ELEMID_RATES:
520 			scan->rates = frm;
521 			break;
522 		case IEEE80211_ELEMID_COUNTRY:
523 			scan->country = frm;
524 			break;
525 		case IEEE80211_ELEMID_CSA:
526 			scan->csa = frm;
527 			break;
528 		case IEEE80211_ELEMID_QUIET:
529 			scan->quiet = frm;
530 			break;
531 		case IEEE80211_ELEMID_FHPARMS:
532 			if (ic->ic_phytype == IEEE80211_T_FH) {
533 				scan->fhdwell = LE_READ_2(&frm[2]);
534 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
535 				scan->fhindex = frm[6];
536 			}
537 			break;
538 		case IEEE80211_ELEMID_DSPARMS:
539 			/*
540 			 * XXX hack this since depending on phytype
541 			 * is problematic for multi-mode devices.
542 			 */
543 			if (ic->ic_phytype != IEEE80211_T_FH)
544 				scan->chan = frm[2];
545 			break;
546 		case IEEE80211_ELEMID_TIM:
547 			/* XXX ATIM? */
548 			scan->tim = frm;
549 			scan->timoff = frm - mtod(m, uint8_t *);
550 			break;
551 		case IEEE80211_ELEMID_IBSSPARMS:
552 		case IEEE80211_ELEMID_CFPARMS:
553 		case IEEE80211_ELEMID_PWRCNSTR:
554 			/* NB: avoid debugging complaints */
555 			break;
556 		case IEEE80211_ELEMID_XRATES:
557 			scan->xrates = frm;
558 			break;
559 		case IEEE80211_ELEMID_ERP:
560 			if (frm[1] != 1) {
561 				IEEE80211_DISCARD_IE(vap,
562 				    IEEE80211_MSG_ELEMID, wh, "ERP",
563 				    "bad len %u", frm[1]);
564 				vap->iv_stats.is_rx_elem_toobig++;
565 				break;
566 			}
567 			scan->erp = frm[2] | 0x100;
568 			break;
569 		case IEEE80211_ELEMID_HTCAP:
570 			scan->htcap = frm;
571 			break;
572 		case IEEE80211_ELEMID_RSN:
573 			scan->rsn = frm;
574 			break;
575 		case IEEE80211_ELEMID_HTINFO:
576 			scan->htinfo = frm;
577 			break;
578 #ifdef IEEE80211_SUPPORT_MESH
579 		case IEEE80211_ELEMID_MESHID:
580 			scan->meshid = frm;
581 			break;
582 		case IEEE80211_ELEMID_MESHCONF:
583 			scan->meshconf = frm;
584 			break;
585 #endif
586 		case IEEE80211_ELEMID_VENDOR:
587 			if (iswpaoui(frm))
588 				scan->wpa = frm;
589 			else if (iswmeparam(frm) || iswmeinfo(frm))
590 				scan->wme = frm;
591 #ifdef IEEE80211_SUPPORT_SUPERG
592 			else if (isatherosoui(frm))
593 				scan->ath = frm;
594 #endif
595 #ifdef IEEE80211_SUPPORT_TDMA
596 			else if (istdmaoui(frm))
597 				scan->tdma = frm;
598 #endif
599 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
600 				/*
601 				 * Accept pre-draft HT ie's if the
602 				 * standard ones have not been seen.
603 				 */
604 				if (ishtcapoui(frm)) {
605 					if (scan->htcap == NULL)
606 						scan->htcap = frm;
607 				} else if (ishtinfooui(frm)) {
608 					if (scan->htinfo == NULL)
609 						scan->htcap = frm;
610 				}
611 			}
612 			break;
613 		default:
614 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
615 			    wh, "unhandled",
616 			    "id %u, len %u", *frm, frm[1]);
617 			vap->iv_stats.is_rx_elem_unknown++;
618 			break;
619 		}
620 		frm += frm[1] + 2;
621 	}
622 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
623 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
624 	if (scan->rates != NULL && scan->xrates != NULL) {
625 		/*
626 		 * NB: don't process XRATES if RATES is missing.  This
627 		 * avoids a potential null ptr deref and should be ok
628 		 * as the return code will already note RATES is missing
629 		 * (so callers shouldn't otherwise process the frame).
630 		 */
631 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
632 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
633 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
634 	}
635 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
636 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
637 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
638 		/*
639 		 * Frame was received on a channel different from the
640 		 * one indicated in the DS params element id;
641 		 * silently discard it.
642 		 *
643 		 * NB: this can happen due to signal leakage.
644 		 *     But we should take it for FH phy because
645 		 *     the rssi value should be correct even for
646 		 *     different hop pattern in FH.
647 		 */
648 		IEEE80211_DISCARD(vap,
649 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
650 		    wh, NULL, "for off-channel %u", scan->chan);
651 		vap->iv_stats.is_rx_chanmismatch++;
652 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
653 	}
654 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
655 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
656 		IEEE80211_DISCARD(vap,
657 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
658 		    wh, NULL, "bogus beacon interval (%d TU)",
659 		    (int) scan->bintval);
660 		vap->iv_stats.is_rx_badbintval++;
661 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
662 	}
663 	if (scan->country != NULL) {
664 		/*
665 		 * Validate we have at least enough data to extract
666 		 * the country code.  Not sure if we should return an
667 		 * error instead of discarding the IE; consider this
668 		 * being lenient as we don't depend on the data for
669 		 * correct operation.
670 		 */
671 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
672 		    scan->country = NULL);
673 	}
674 	if (scan->csa != NULL) {
675 		/*
676 		 * Validate Channel Switch Announcement; this must
677 		 * be the correct length or we toss the frame.
678 		 */
679 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
680 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
681 	}
682 	/*
683 	 * Process HT ie's.  This is complicated by our
684 	 * accepting both the standard ie's and the pre-draft
685 	 * vendor OUI ie's that some vendors still use/require.
686 	 */
687 	if (scan->htcap != NULL) {
688 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
689 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
690 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
691 			 sizeof(struct ieee80211_ie_htcap)-2,
692 		     scan->htcap = NULL);
693 	}
694 	if (scan->htinfo != NULL) {
695 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
696 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
697 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
698 			 sizeof(struct ieee80211_ie_htinfo)-2,
699 		     scan->htinfo = NULL);
700 	}
701 	return scan->status;
702 }
703 
704 /*
705  * Parse an Action frame.  Return 0 on success, non-zero on failure.
706  */
707 int
708 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
709 {
710 	struct ieee80211vap *vap = ni->ni_vap;
711 	const struct ieee80211_action *ia;
712 	struct ieee80211_frame *wh;
713 	uint8_t *frm, *efrm;
714 
715 	/*
716 	 * action frame format:
717 	 *	[1] category
718 	 *	[1] action
719 	 *	[tlv] parameters
720 	 */
721 	wh = mtod(m, struct ieee80211_frame *);
722 	frm = (u_int8_t *)&wh[1];
723 	efrm = mtod(m, u_int8_t *) + m->m_len;
724 	IEEE80211_VERIFY_LENGTH(efrm - frm,
725 		sizeof(struct ieee80211_action), return EINVAL);
726 	ia = (const struct ieee80211_action *) frm;
727 
728 	vap->iv_stats.is_rx_action++;
729 	IEEE80211_NODE_STAT(ni, rx_action);
730 
731 	/* verify frame payloads but defer processing */
732 	switch (ia->ia_category) {
733 	case IEEE80211_ACTION_CAT_BA:
734 		switch (ia->ia_action) {
735 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
736 			IEEE80211_VERIFY_LENGTH(efrm - frm,
737 			    sizeof(struct ieee80211_action_ba_addbarequest),
738 			    return EINVAL);
739 			break;
740 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
741 			IEEE80211_VERIFY_LENGTH(efrm - frm,
742 			    sizeof(struct ieee80211_action_ba_addbaresponse),
743 			    return EINVAL);
744 			break;
745 		case IEEE80211_ACTION_BA_DELBA:
746 			IEEE80211_VERIFY_LENGTH(efrm - frm,
747 			    sizeof(struct ieee80211_action_ba_delba),
748 			    return EINVAL);
749 			break;
750 		}
751 		break;
752 	case IEEE80211_ACTION_CAT_HT:
753 		switch (ia->ia_action) {
754 		case IEEE80211_ACTION_HT_TXCHWIDTH:
755 			IEEE80211_VERIFY_LENGTH(efrm - frm,
756 			    sizeof(struct ieee80211_action_ht_txchwidth),
757 			    return EINVAL);
758 			break;
759 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
760 			IEEE80211_VERIFY_LENGTH(efrm - frm,
761 			    sizeof(struct ieee80211_action_ht_mimopowersave),
762 			    return EINVAL);
763 			break;
764 		}
765 		break;
766 #ifdef IEEE80211_SUPPORT_MESH
767 	case IEEE80211_ACTION_CAT_MESH:
768 		switch (ia->ia_action) {
769 		case IEEE80211_ACTION_MESH_LMETRIC:
770 			/*
771 			 * XXX: verification is true only if we are using
772 			 * Airtime link metric (default)
773 			 */
774 			IEEE80211_VERIFY_LENGTH(efrm - frm,
775 			    sizeof(struct ieee80211_meshlmetric_ie),
776 			    return EINVAL);
777 			break;
778 		case IEEE80211_ACTION_MESH_HWMP:
779 			/* verify something */
780 			break;
781 		case IEEE80211_ACTION_MESH_GANN:
782 			IEEE80211_VERIFY_LENGTH(efrm - frm,
783 			    sizeof(struct ieee80211_meshgann_ie),
784 			    return EINVAL);
785 			break;
786 		case IEEE80211_ACTION_MESH_CC:
787 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
788 		case IEEE80211_ACTION_MESH_MCCA_SREP:
789 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
790 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
791 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
792 		case IEEE80211_ACTION_MESH_TBTT_REQ:
793 		case IEEE80211_ACTION_MESH_TBTT_RES:
794 			/* reject these early on, not implemented */
795 			IEEE80211_DISCARD(vap,
796 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
797 			    wh, NULL, "not implemented yet, act=0x%02X",
798 			    ia->ia_action);
799 			return EINVAL;
800 		}
801 		break;
802 	case IEEE80211_ACTION_CAT_SELF_PROT:
803 		/* If TA or RA group address discard silently */
804 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
805 			IEEE80211_IS_MULTICAST(wh->i_addr2))
806 			return EINVAL;
807 		/*
808 		 * XXX: Should we verify complete length now or it is
809 		 * to varying in sizes?
810 		 */
811 		switch (ia->ia_action) {
812 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
813 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
814 			/* is not a peering candidate (yet) */
815 			if (ni == vap->iv_bss)
816 				return EINVAL;
817 			break;
818 		}
819 		break;
820 #endif
821 	}
822 	return 0;
823 }
824 
825 #ifdef IEEE80211_DEBUG
826 /*
827  * Debugging support.
828  */
829 void
830 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
831 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
832 {
833 	printf("[%s] discard %s frame, ssid mismatch: ",
834 		ether_sprintf(mac), tag);
835 	ieee80211_print_essid(ssid + 2, ssid[1]);
836 	printf("\n");
837 }
838 
839 /*
840  * Return the bssid of a frame.
841  */
842 static const uint8_t *
843 ieee80211_getbssid(const struct ieee80211vap *vap,
844 	const struct ieee80211_frame *wh)
845 {
846 	if (vap->iv_opmode == IEEE80211_M_STA)
847 		return wh->i_addr2;
848 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
849 		return wh->i_addr1;
850 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
851 		return wh->i_addr1;
852 	return wh->i_addr3;
853 }
854 
855 #include <machine/stdarg.h>
856 
857 void
858 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
859 {
860 	char buf[128];		/* XXX */
861 	va_list ap;
862 
863 	va_start(ap, fmt);
864 	vsnprintf(buf, sizeof(buf), fmt, ap);
865 	va_end(ap);
866 
867 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
868 }
869 
870 void
871 ieee80211_note_frame(const struct ieee80211vap *vap,
872 	const struct ieee80211_frame *wh,
873 	const char *fmt, ...)
874 {
875 	char buf[128];		/* XXX */
876 	va_list ap;
877 
878 	va_start(ap, fmt);
879 	vsnprintf(buf, sizeof(buf), fmt, ap);
880 	va_end(ap);
881 	if_printf(vap->iv_ifp, "[%s] %s\n",
882 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
883 }
884 
885 void
886 ieee80211_note_mac(const struct ieee80211vap *vap,
887 	const uint8_t mac[IEEE80211_ADDR_LEN],
888 	const char *fmt, ...)
889 {
890 	char buf[128];		/* XXX */
891 	va_list ap;
892 
893 	va_start(ap, fmt);
894 	vsnprintf(buf, sizeof(buf), fmt, ap);
895 	va_end(ap);
896 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
897 }
898 
899 void
900 ieee80211_discard_frame(const struct ieee80211vap *vap,
901 	const struct ieee80211_frame *wh,
902 	const char *type, const char *fmt, ...)
903 {
904 	va_list ap;
905 
906 	if_printf(vap->iv_ifp, "[%s] discard ",
907 		ether_sprintf(ieee80211_getbssid(vap, wh)));
908 	if (type == NULL) {
909 		printf("%s frame, ", ieee80211_mgt_subtype_name[
910 			(wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) >>
911 			IEEE80211_FC0_SUBTYPE_SHIFT]);
912 	} else
913 		printf("%s frame, ", type);
914 	va_start(ap, fmt);
915 	vprintf(fmt, ap);
916 	va_end(ap);
917 	printf("\n");
918 }
919 
920 void
921 ieee80211_discard_ie(const struct ieee80211vap *vap,
922 	const struct ieee80211_frame *wh,
923 	const char *type, const char *fmt, ...)
924 {
925 	va_list ap;
926 
927 	if_printf(vap->iv_ifp, "[%s] discard ",
928 		ether_sprintf(ieee80211_getbssid(vap, wh)));
929 	if (type != NULL)
930 		printf("%s information element, ", type);
931 	else
932 		printf("information element, ");
933 	va_start(ap, fmt);
934 	vprintf(fmt, ap);
935 	va_end(ap);
936 	printf("\n");
937 }
938 
939 void
940 ieee80211_discard_mac(const struct ieee80211vap *vap,
941 	const uint8_t mac[IEEE80211_ADDR_LEN],
942 	const char *type, const char *fmt, ...)
943 {
944 	va_list ap;
945 
946 	if_printf(vap->iv_ifp, "[%s] discard ", ether_sprintf(mac));
947 	if (type != NULL)
948 		printf("%s frame, ", type);
949 	else
950 		printf("frame, ");
951 	va_start(ap, fmt);
952 	vprintf(fmt, ap);
953 	va_end(ap);
954 	printf("\n");
955 }
956 #endif /* IEEE80211_DEBUG */
957