xref: /freebsd/sys/net80211/ieee80211_input.c (revision 617aa98c6c25406d90089351dbdf69d3a205f49d)
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_var.h>
44 #include <net/if_llc.h>
45 #include <net/if_media.h>
46 #include <net/if_vlan_var.h>
47 
48 #include <net80211/ieee80211_var.h>
49 #include <net80211/ieee80211_input.h>
50 #ifdef IEEE80211_SUPPORT_MESH
51 #include <net80211/ieee80211_mesh.h>
52 #endif
53 
54 #include <net/bpf.h>
55 
56 #ifdef INET
57 #include <netinet/in.h>
58 #include <net/ethernet.h>
59 #endif
60 
61 static void
62 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
63 {
64 	int i;
65 
66 	/* Verify the required MIMO bits are set */
67 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
68 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
69 		return;
70 
71 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
72 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
73 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
74 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
75 	}
76 
77 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
78 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
79 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
80 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
81 	}
82 	ni->ni_mimo_chains = rx->c_chain;
83 }
84 
85 int
86 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
87     struct ieee80211_rx_stats *rx)
88 {
89 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
90 	ieee80211_process_mimo(ni, rx);
91 	return ieee80211_input(ni, m, rx->rssi, rx->nf);
92 }
93 
94 int
95 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
96 {
97 	struct ieee80211_rx_stats rx;
98 
99 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
100 	rx.nf = nf;
101 	rx.rssi = rssi;
102 	return ieee80211_input_mimo_all(ic, m, &rx);
103 }
104 
105 int
106 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
107     struct ieee80211_rx_stats *rx)
108 {
109 	struct ieee80211vap *vap;
110 	int type = -1;
111 
112 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
113 
114 	/* XXX locking */
115 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
116 		struct ieee80211_node *ni;
117 		struct mbuf *mcopy;
118 
119 		/* NB: could check for IFF_UP but this is cheaper */
120 		if (vap->iv_state == IEEE80211_S_INIT)
121 			continue;
122 		/*
123 		 * WDS vap's only receive directed traffic from the
124 		 * station at the ``far end''.  That traffic should
125 		 * be passed through the AP vap the station is associated
126 		 * to--so don't spam them with mcast frames.
127 		 */
128 		if (vap->iv_opmode == IEEE80211_M_WDS)
129 			continue;
130 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
131 			/*
132 			 * Packet contents are changed by ieee80211_decap
133 			 * so do a deep copy of the packet.
134 			 */
135 			mcopy = m_dup(m, M_NOWAIT);
136 			if (mcopy == NULL) {
137 				/* XXX stat+msg */
138 				continue;
139 			}
140 		} else {
141 			mcopy = m;
142 			m = NULL;
143 		}
144 		ni = ieee80211_ref_node(vap->iv_bss);
145 		type = ieee80211_input_mimo(ni, mcopy, rx);
146 		ieee80211_free_node(ni);
147 	}
148 	if (m != NULL)			/* no vaps, reclaim mbuf */
149 		m_freem(m);
150 	return type;
151 }
152 
153 /*
154  * This function reassembles fragments.
155  *
156  * XXX should handle 3 concurrent reassemblies per-spec.
157  */
158 struct mbuf *
159 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
160 {
161 	struct ieee80211vap *vap = ni->ni_vap;
162 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
163 	struct ieee80211_frame *lwh;
164 	uint16_t rxseq;
165 	uint8_t fragno;
166 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
167 	struct mbuf *mfrag;
168 
169 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
170 
171 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
172 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
173 
174 	/* Quick way out, if there's nothing to defragment */
175 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
176 		return m;
177 
178 	/*
179 	 * Remove frag to insure it doesn't get reaped by timer.
180 	 */
181 	if (ni->ni_table == NULL) {
182 		/*
183 		 * Should never happen.  If the node is orphaned (not in
184 		 * the table) then input packets should not reach here.
185 		 * Otherwise, a concurrent request that yanks the table
186 		 * should be blocked by other interlocking and/or by first
187 		 * shutting the driver down.  Regardless, be defensive
188 		 * here and just bail
189 		 */
190 		/* XXX need msg+stat */
191 		m_freem(m);
192 		return NULL;
193 	}
194 	IEEE80211_NODE_LOCK(ni->ni_table);
195 	mfrag = ni->ni_rxfrag[0];
196 	ni->ni_rxfrag[0] = NULL;
197 	IEEE80211_NODE_UNLOCK(ni->ni_table);
198 
199 	/*
200 	 * Validate new fragment is in order and
201 	 * related to the previous ones.
202 	 */
203 	if (mfrag != NULL) {
204 		uint16_t last_rxseq;
205 
206 		lwh = mtod(mfrag, struct ieee80211_frame *);
207 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
208 		/* NB: check seq # and frag together */
209 		if (rxseq != last_rxseq+1 ||
210 		    !IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) ||
211 		    !IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
212 			/*
213 			 * Unrelated fragment or no space for it,
214 			 * clear current fragments.
215 			 */
216 			m_freem(mfrag);
217 			mfrag = NULL;
218 		}
219 	}
220 
221  	if (mfrag == NULL) {
222 		if (fragno != 0) {		/* !first fragment, discard */
223 			vap->iv_stats.is_rx_defrag++;
224 			IEEE80211_NODE_STAT(ni, rx_defrag);
225 			m_freem(m);
226 			return NULL;
227 		}
228 		mfrag = m;
229 	} else {				/* concatenate */
230 		m_adj(m, hdrspace);		/* strip header */
231 		m_cat(mfrag, m);
232 		/* NB: m_cat doesn't update the packet header */
233 		mfrag->m_pkthdr.len += m->m_pkthdr.len;
234 		/* track last seqnum and fragno */
235 		lwh = mtod(mfrag, struct ieee80211_frame *);
236 		*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
237 	}
238 	if (more_frag) {			/* more to come, save */
239 		ni->ni_rxfragstamp = ticks;
240 		ni->ni_rxfrag[0] = mfrag;
241 		mfrag = NULL;
242 	}
243 	return mfrag;
244 }
245 
246 void
247 ieee80211_deliver_data(struct ieee80211vap *vap,
248 	struct ieee80211_node *ni, struct mbuf *m)
249 {
250 	struct ether_header *eh = mtod(m, struct ether_header *);
251 	struct ifnet *ifp = vap->iv_ifp;
252 
253 	/* clear driver/net80211 flags before passing up */
254 	m->m_flags &= ~(M_MCAST | M_BCAST);
255 #if __FreeBSD_version >= 1000046
256 	m_clrprotoflags(m);
257 #endif
258 
259 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
260 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
261 	/*
262 	 * Do accounting.
263 	 */
264 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
265 	IEEE80211_NODE_STAT(ni, rx_data);
266 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
267 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
268 		m->m_flags |= M_MCAST;		/* XXX M_BCAST? */
269 		IEEE80211_NODE_STAT(ni, rx_mcast);
270 	} else
271 		IEEE80211_NODE_STAT(ni, rx_ucast);
272 	m->m_pkthdr.rcvif = ifp;
273 
274 	if (ni->ni_vlan != 0) {
275 		/* attach vlan tag */
276 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
277 		m->m_flags |= M_VLANTAG;
278 	}
279 	ifp->if_input(ifp, m);
280 }
281 
282 struct mbuf *
283 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
284 {
285 	struct ieee80211_qosframe_addr4 wh;
286 	struct ether_header *eh;
287 	struct llc *llc;
288 
289 	KASSERT(hdrlen <= sizeof(wh),
290 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
291 
292 	if (m->m_len < hdrlen + sizeof(*llc) &&
293 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
294 		vap->iv_stats.is_rx_tooshort++;
295 		/* XXX msg */
296 		return NULL;
297 	}
298 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
299 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
300 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
301 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
302 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
303 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
304 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
305 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
306 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
307 		llc = NULL;
308 	} else {
309 		m_adj(m, hdrlen - sizeof(*eh));
310 	}
311 	eh = mtod(m, struct ether_header *);
312 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
313 	case IEEE80211_FC1_DIR_NODS:
314 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
315 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
316 		break;
317 	case IEEE80211_FC1_DIR_TODS:
318 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
319 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
320 		break;
321 	case IEEE80211_FC1_DIR_FROMDS:
322 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
323 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
324 		break;
325 	case IEEE80211_FC1_DIR_DSTODS:
326 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
327 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
328 		break;
329 	}
330 #ifndef __NO_STRICT_ALIGNMENT
331 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
332 		m = ieee80211_realign(vap, m, sizeof(*eh));
333 		if (m == NULL)
334 			return NULL;
335 	}
336 #endif /* !__NO_STRICT_ALIGNMENT */
337 	if (llc != NULL) {
338 		eh = mtod(m, struct ether_header *);
339 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
340 	}
341 	return m;
342 }
343 
344 /*
345  * Decap a frame encapsulated in a fast-frame/A-MSDU.
346  */
347 struct mbuf *
348 ieee80211_decap1(struct mbuf *m, int *framelen)
349 {
350 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
351 	struct ether_header *eh;
352 	struct llc *llc;
353 
354 	/*
355 	 * The frame has an 802.3 header followed by an 802.2
356 	 * LLC header.  The encapsulated frame length is in the
357 	 * first header type field; save that and overwrite it
358 	 * with the true type field found in the second.  Then
359 	 * copy the 802.3 header up to where it belongs and
360 	 * adjust the mbuf contents to remove the void.
361 	 */
362 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
363 		return NULL;
364 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
365 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
366 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
367 		  + sizeof(struct ether_header) - sizeof(struct llc);
368 	eh->ether_type = llc->llc_un.type_snap.ether_type;
369 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
370 		sizeof(struct ether_header));
371 	m_adj(m, sizeof(struct llc));
372 	return m;
373 #undef FF_LLC_SIZE
374 }
375 
376 /*
377  * Install received rate set information in the node's state block.
378  */
379 int
380 ieee80211_setup_rates(struct ieee80211_node *ni,
381 	const uint8_t *rates, const uint8_t *xrates, int flags)
382 {
383 	struct ieee80211vap *vap = ni->ni_vap;
384 	struct ieee80211_rateset *rs = &ni->ni_rates;
385 
386 	memset(rs, 0, sizeof(*rs));
387 	rs->rs_nrates = rates[1];
388 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
389 	if (xrates != NULL) {
390 		uint8_t nxrates;
391 		/*
392 		 * Tack on 11g extended supported rate element.
393 		 */
394 		nxrates = xrates[1];
395 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
396 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
397 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
398 			    "extended rate set too large; only using "
399 			    "%u of %u rates", nxrates, xrates[1]);
400 			vap->iv_stats.is_rx_rstoobig++;
401 		}
402 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
403 		rs->rs_nrates += nxrates;
404 	}
405 	return ieee80211_fix_rate(ni, rs, flags);
406 }
407 
408 /*
409  * Send a management frame error response to the specified
410  * station.  If ni is associated with the station then use
411  * it; otherwise allocate a temporary node suitable for
412  * transmitting the frame and then free the reference so
413  * it will go away as soon as the frame has been transmitted.
414  */
415 void
416 ieee80211_send_error(struct ieee80211_node *ni,
417 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
418 {
419 	struct ieee80211vap *vap = ni->ni_vap;
420 	int istmp;
421 
422 	if (ni == vap->iv_bss) {
423 		if (vap->iv_state != IEEE80211_S_RUN) {
424 			/*
425 			 * XXX hack until we get rid of this routine.
426 			 * We can be called prior to the vap reaching
427 			 * run state under certain conditions in which
428 			 * case iv_bss->ni_chan will not be setup.
429 			 * Check for this explicitly and and just ignore
430 			 * the request.
431 			 */
432 			return;
433 		}
434 		ni = ieee80211_tmp_node(vap, mac);
435 		if (ni == NULL) {
436 			/* XXX msg */
437 			return;
438 		}
439 		istmp = 1;
440 	} else
441 		istmp = 0;
442 	IEEE80211_SEND_MGMT(ni, subtype, arg);
443 	if (istmp)
444 		ieee80211_free_node(ni);
445 }
446 
447 int
448 ieee80211_alloc_challenge(struct ieee80211_node *ni)
449 {
450 	if (ni->ni_challenge == NULL)
451 		ni->ni_challenge = (uint32_t *) malloc(IEEE80211_CHALLENGE_LEN,
452 		    M_80211_NODE, M_NOWAIT);
453 	if (ni->ni_challenge == NULL) {
454 		IEEE80211_NOTE(ni->ni_vap,
455 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
456 		    "%s", "shared key challenge alloc failed");
457 		/* XXX statistic */
458 	}
459 	return (ni->ni_challenge != NULL);
460 }
461 
462 /*
463  * Parse a Beacon or ProbeResponse frame and return the
464  * useful information in an ieee80211_scanparams structure.
465  * Status is set to 0 if no problems were found; otherwise
466  * a bitmask of IEEE80211_BPARSE_* items is returned that
467  * describes the problems detected.
468  */
469 int
470 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
471 	struct ieee80211_scanparams *scan)
472 {
473 	struct ieee80211vap *vap = ni->ni_vap;
474 	struct ieee80211com *ic = ni->ni_ic;
475 	struct ieee80211_frame *wh;
476 	uint8_t *frm, *efrm;
477 
478 	wh = mtod(m, struct ieee80211_frame *);
479 	frm = (uint8_t *)&wh[1];
480 	efrm = mtod(m, uint8_t *) + m->m_len;
481 	scan->status = 0;
482 	/*
483 	 * beacon/probe response frame format
484 	 *	[8] time stamp
485 	 *	[2] beacon interval
486 	 *	[2] capability information
487 	 *	[tlv] ssid
488 	 *	[tlv] supported rates
489 	 *	[tlv] country information
490 	 *	[tlv] channel switch announcement (CSA)
491 	 *	[tlv] parameter set (FH/DS)
492 	 *	[tlv] erp information
493 	 *	[tlv] extended supported rates
494 	 *	[tlv] WME
495 	 *	[tlv] WPA or RSN
496 	 *	[tlv] HT capabilities
497 	 *	[tlv] HT information
498 	 *	[tlv] Atheros capabilities
499 	 *	[tlv] Mesh ID
500 	 *	[tlv] Mesh Configuration
501 	 */
502 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
503 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
504 	memset(scan, 0, sizeof(*scan));
505 	scan->tstamp  = frm;				frm += 8;
506 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
507 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
508 	scan->bchan = ieee80211_chan2ieee(ic, ic->ic_curchan);
509 	scan->chan = scan->bchan;
510 	scan->ies = frm;
511 	scan->ies_len = efrm - frm;
512 
513 	while (efrm - frm > 1) {
514 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
515 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
516 		switch (*frm) {
517 		case IEEE80211_ELEMID_SSID:
518 			scan->ssid = frm;
519 			break;
520 		case IEEE80211_ELEMID_RATES:
521 			scan->rates = frm;
522 			break;
523 		case IEEE80211_ELEMID_COUNTRY:
524 			scan->country = frm;
525 			break;
526 		case IEEE80211_ELEMID_CSA:
527 			scan->csa = frm;
528 			break;
529 		case IEEE80211_ELEMID_QUIET:
530 			scan->quiet = frm;
531 			break;
532 		case IEEE80211_ELEMID_FHPARMS:
533 			if (ic->ic_phytype == IEEE80211_T_FH) {
534 				scan->fhdwell = LE_READ_2(&frm[2]);
535 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
536 				scan->fhindex = frm[6];
537 			}
538 			break;
539 		case IEEE80211_ELEMID_DSPARMS:
540 			/*
541 			 * XXX hack this since depending on phytype
542 			 * is problematic for multi-mode devices.
543 			 */
544 			if (ic->ic_phytype != IEEE80211_T_FH)
545 				scan->chan = frm[2];
546 			break;
547 		case IEEE80211_ELEMID_TIM:
548 			/* XXX ATIM? */
549 			scan->tim = frm;
550 			scan->timoff = frm - mtod(m, uint8_t *);
551 			break;
552 		case IEEE80211_ELEMID_IBSSPARMS:
553 		case IEEE80211_ELEMID_CFPARMS:
554 		case IEEE80211_ELEMID_PWRCNSTR:
555 			/* NB: avoid debugging complaints */
556 			break;
557 		case IEEE80211_ELEMID_XRATES:
558 			scan->xrates = frm;
559 			break;
560 		case IEEE80211_ELEMID_ERP:
561 			if (frm[1] != 1) {
562 				IEEE80211_DISCARD_IE(vap,
563 				    IEEE80211_MSG_ELEMID, wh, "ERP",
564 				    "bad len %u", frm[1]);
565 				vap->iv_stats.is_rx_elem_toobig++;
566 				break;
567 			}
568 			scan->erp = frm[2] | 0x100;
569 			break;
570 		case IEEE80211_ELEMID_HTCAP:
571 			scan->htcap = frm;
572 			break;
573 		case IEEE80211_ELEMID_RSN:
574 			scan->rsn = frm;
575 			break;
576 		case IEEE80211_ELEMID_HTINFO:
577 			scan->htinfo = frm;
578 			break;
579 #ifdef IEEE80211_SUPPORT_MESH
580 		case IEEE80211_ELEMID_MESHID:
581 			scan->meshid = frm;
582 			break;
583 		case IEEE80211_ELEMID_MESHCONF:
584 			scan->meshconf = frm;
585 			break;
586 #endif
587 		case IEEE80211_ELEMID_VENDOR:
588 			if (iswpaoui(frm))
589 				scan->wpa = frm;
590 			else if (iswmeparam(frm) || iswmeinfo(frm))
591 				scan->wme = frm;
592 #ifdef IEEE80211_SUPPORT_SUPERG
593 			else if (isatherosoui(frm))
594 				scan->ath = frm;
595 #endif
596 #ifdef IEEE80211_SUPPORT_TDMA
597 			else if (istdmaoui(frm))
598 				scan->tdma = frm;
599 #endif
600 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
601 				/*
602 				 * Accept pre-draft HT ie's if the
603 				 * standard ones have not been seen.
604 				 */
605 				if (ishtcapoui(frm)) {
606 					if (scan->htcap == NULL)
607 						scan->htcap = frm;
608 				} else if (ishtinfooui(frm)) {
609 					if (scan->htinfo == NULL)
610 						scan->htcap = frm;
611 				}
612 			}
613 			break;
614 		default:
615 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
616 			    wh, "unhandled",
617 			    "id %u, len %u", *frm, frm[1]);
618 			vap->iv_stats.is_rx_elem_unknown++;
619 			break;
620 		}
621 		frm += frm[1] + 2;
622 	}
623 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
624 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
625 	if (scan->rates != NULL && scan->xrates != NULL) {
626 		/*
627 		 * NB: don't process XRATES if RATES is missing.  This
628 		 * avoids a potential null ptr deref and should be ok
629 		 * as the return code will already note RATES is missing
630 		 * (so callers shouldn't otherwise process the frame).
631 		 */
632 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
633 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
634 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
635 	}
636 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
637 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
638 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
639 		/*
640 		 * Frame was received on a channel different from the
641 		 * one indicated in the DS params element id;
642 		 * silently discard it.
643 		 *
644 		 * NB: this can happen due to signal leakage.
645 		 *     But we should take it for FH phy because
646 		 *     the rssi value should be correct even for
647 		 *     different hop pattern in FH.
648 		 */
649 		IEEE80211_DISCARD(vap,
650 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
651 		    wh, NULL, "for off-channel %u", scan->chan);
652 		vap->iv_stats.is_rx_chanmismatch++;
653 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
654 	}
655 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
656 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
657 		IEEE80211_DISCARD(vap,
658 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
659 		    wh, NULL, "bogus beacon interval (%d TU)",
660 		    (int) scan->bintval);
661 		vap->iv_stats.is_rx_badbintval++;
662 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
663 	}
664 	if (scan->country != NULL) {
665 		/*
666 		 * Validate we have at least enough data to extract
667 		 * the country code.  Not sure if we should return an
668 		 * error instead of discarding the IE; consider this
669 		 * being lenient as we don't depend on the data for
670 		 * correct operation.
671 		 */
672 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
673 		    scan->country = NULL);
674 	}
675 	if (scan->csa != NULL) {
676 		/*
677 		 * Validate Channel Switch Announcement; this must
678 		 * be the correct length or we toss the frame.
679 		 */
680 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
681 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
682 	}
683 	/*
684 	 * Process HT ie's.  This is complicated by our
685 	 * accepting both the standard ie's and the pre-draft
686 	 * vendor OUI ie's that some vendors still use/require.
687 	 */
688 	if (scan->htcap != NULL) {
689 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
690 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
691 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
692 			 sizeof(struct ieee80211_ie_htcap)-2,
693 		     scan->htcap = NULL);
694 	}
695 	if (scan->htinfo != NULL) {
696 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
697 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
698 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
699 			 sizeof(struct ieee80211_ie_htinfo)-2,
700 		     scan->htinfo = NULL);
701 	}
702 	return scan->status;
703 }
704 
705 /*
706  * Parse an Action frame.  Return 0 on success, non-zero on failure.
707  */
708 int
709 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
710 {
711 	struct ieee80211vap *vap = ni->ni_vap;
712 	const struct ieee80211_action *ia;
713 	struct ieee80211_frame *wh;
714 	uint8_t *frm, *efrm;
715 
716 	/*
717 	 * action frame format:
718 	 *	[1] category
719 	 *	[1] action
720 	 *	[tlv] parameters
721 	 */
722 	wh = mtod(m, struct ieee80211_frame *);
723 	frm = (u_int8_t *)&wh[1];
724 	efrm = mtod(m, u_int8_t *) + m->m_len;
725 	IEEE80211_VERIFY_LENGTH(efrm - frm,
726 		sizeof(struct ieee80211_action), return EINVAL);
727 	ia = (const struct ieee80211_action *) frm;
728 
729 	vap->iv_stats.is_rx_action++;
730 	IEEE80211_NODE_STAT(ni, rx_action);
731 
732 	/* verify frame payloads but defer processing */
733 	switch (ia->ia_category) {
734 	case IEEE80211_ACTION_CAT_BA:
735 		switch (ia->ia_action) {
736 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
737 			IEEE80211_VERIFY_LENGTH(efrm - frm,
738 			    sizeof(struct ieee80211_action_ba_addbarequest),
739 			    return EINVAL);
740 			break;
741 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
742 			IEEE80211_VERIFY_LENGTH(efrm - frm,
743 			    sizeof(struct ieee80211_action_ba_addbaresponse),
744 			    return EINVAL);
745 			break;
746 		case IEEE80211_ACTION_BA_DELBA:
747 			IEEE80211_VERIFY_LENGTH(efrm - frm,
748 			    sizeof(struct ieee80211_action_ba_delba),
749 			    return EINVAL);
750 			break;
751 		}
752 		break;
753 	case IEEE80211_ACTION_CAT_HT:
754 		switch (ia->ia_action) {
755 		case IEEE80211_ACTION_HT_TXCHWIDTH:
756 			IEEE80211_VERIFY_LENGTH(efrm - frm,
757 			    sizeof(struct ieee80211_action_ht_txchwidth),
758 			    return EINVAL);
759 			break;
760 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
761 			IEEE80211_VERIFY_LENGTH(efrm - frm,
762 			    sizeof(struct ieee80211_action_ht_mimopowersave),
763 			    return EINVAL);
764 			break;
765 		}
766 		break;
767 #ifdef IEEE80211_SUPPORT_MESH
768 	case IEEE80211_ACTION_CAT_MESH:
769 		switch (ia->ia_action) {
770 		case IEEE80211_ACTION_MESH_LMETRIC:
771 			/*
772 			 * XXX: verification is true only if we are using
773 			 * Airtime link metric (default)
774 			 */
775 			IEEE80211_VERIFY_LENGTH(efrm - frm,
776 			    sizeof(struct ieee80211_meshlmetric_ie),
777 			    return EINVAL);
778 			break;
779 		case IEEE80211_ACTION_MESH_HWMP:
780 			/* verify something */
781 			break;
782 		case IEEE80211_ACTION_MESH_GANN:
783 			IEEE80211_VERIFY_LENGTH(efrm - frm,
784 			    sizeof(struct ieee80211_meshgann_ie),
785 			    return EINVAL);
786 			break;
787 		case IEEE80211_ACTION_MESH_CC:
788 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
789 		case IEEE80211_ACTION_MESH_MCCA_SREP:
790 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
791 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
792 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
793 		case IEEE80211_ACTION_MESH_TBTT_REQ:
794 		case IEEE80211_ACTION_MESH_TBTT_RES:
795 			/* reject these early on, not implemented */
796 			IEEE80211_DISCARD(vap,
797 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
798 			    wh, NULL, "not implemented yet, act=0x%02X",
799 			    ia->ia_action);
800 			return EINVAL;
801 		}
802 		break;
803 	case IEEE80211_ACTION_CAT_SELF_PROT:
804 		/* If TA or RA group address discard silently */
805 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
806 			IEEE80211_IS_MULTICAST(wh->i_addr2))
807 			return EINVAL;
808 		/*
809 		 * XXX: Should we verify complete length now or it is
810 		 * to varying in sizes?
811 		 */
812 		switch (ia->ia_action) {
813 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
814 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
815 			/* is not a peering candidate (yet) */
816 			if (ni == vap->iv_bss)
817 				return EINVAL;
818 			break;
819 		}
820 		break;
821 #endif
822 	}
823 	return 0;
824 }
825 
826 #ifdef IEEE80211_DEBUG
827 /*
828  * Debugging support.
829  */
830 void
831 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
832 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
833 {
834 	printf("[%s] discard %s frame, ssid mismatch: ",
835 		ether_sprintf(mac), tag);
836 	ieee80211_print_essid(ssid + 2, ssid[1]);
837 	printf("\n");
838 }
839 
840 /*
841  * Return the bssid of a frame.
842  */
843 static const uint8_t *
844 ieee80211_getbssid(const struct ieee80211vap *vap,
845 	const struct ieee80211_frame *wh)
846 {
847 	if (vap->iv_opmode == IEEE80211_M_STA)
848 		return wh->i_addr2;
849 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
850 		return wh->i_addr1;
851 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
852 		return wh->i_addr1;
853 	return wh->i_addr3;
854 }
855 
856 #include <machine/stdarg.h>
857 
858 void
859 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
860 {
861 	char buf[128];		/* XXX */
862 	va_list ap;
863 
864 	va_start(ap, fmt);
865 	vsnprintf(buf, sizeof(buf), fmt, ap);
866 	va_end(ap);
867 
868 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
869 }
870 
871 void
872 ieee80211_note_frame(const struct ieee80211vap *vap,
873 	const struct ieee80211_frame *wh,
874 	const char *fmt, ...)
875 {
876 	char buf[128];		/* XXX */
877 	va_list ap;
878 
879 	va_start(ap, fmt);
880 	vsnprintf(buf, sizeof(buf), fmt, ap);
881 	va_end(ap);
882 	if_printf(vap->iv_ifp, "[%s] %s\n",
883 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
884 }
885 
886 void
887 ieee80211_note_mac(const struct ieee80211vap *vap,
888 	const uint8_t mac[IEEE80211_ADDR_LEN],
889 	const char *fmt, ...)
890 {
891 	char buf[128];		/* XXX */
892 	va_list ap;
893 
894 	va_start(ap, fmt);
895 	vsnprintf(buf, sizeof(buf), fmt, ap);
896 	va_end(ap);
897 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
898 }
899 
900 void
901 ieee80211_discard_frame(const struct ieee80211vap *vap,
902 	const struct ieee80211_frame *wh,
903 	const char *type, const char *fmt, ...)
904 {
905 	va_list ap;
906 
907 	if_printf(vap->iv_ifp, "[%s] discard ",
908 		ether_sprintf(ieee80211_getbssid(vap, wh)));
909 	if (type == NULL) {
910 		printf("%s frame, ", ieee80211_mgt_subtype_name[
911 			(wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) >>
912 			IEEE80211_FC0_SUBTYPE_SHIFT]);
913 	} else
914 		printf("%s frame, ", type);
915 	va_start(ap, fmt);
916 	vprintf(fmt, ap);
917 	va_end(ap);
918 	printf("\n");
919 }
920 
921 void
922 ieee80211_discard_ie(const struct ieee80211vap *vap,
923 	const struct ieee80211_frame *wh,
924 	const char *type, const char *fmt, ...)
925 {
926 	va_list ap;
927 
928 	if_printf(vap->iv_ifp, "[%s] discard ",
929 		ether_sprintf(ieee80211_getbssid(vap, wh)));
930 	if (type != NULL)
931 		printf("%s information element, ", type);
932 	else
933 		printf("information element, ");
934 	va_start(ap, fmt);
935 	vprintf(fmt, ap);
936 	va_end(ap);
937 	printf("\n");
938 }
939 
940 void
941 ieee80211_discard_mac(const struct ieee80211vap *vap,
942 	const uint8_t mac[IEEE80211_ADDR_LEN],
943 	const char *type, const char *fmt, ...)
944 {
945 	va_list ap;
946 
947 	if_printf(vap->iv_ifp, "[%s] discard ", ether_sprintf(mac));
948 	if (type != NULL)
949 		printf("%s frame, ", type);
950 	else
951 		printf("frame, ");
952 	va_start(ap, fmt);
953 	vprintf(fmt, ap);
954 	va_end(ap);
955 	printf("\n");
956 }
957 #endif /* IEEE80211_DEBUG */
958