xref: /freebsd/sys/net80211/ieee80211_input.c (revision a687910fc4352117413b8e0275383e4c687d4c4c)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2001 Atsushi Onoe
5  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
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_private.h>
47 #include <net/if_vlan_var.h>
48 
49 #include <net80211/ieee80211_var.h>
50 #include <net80211/ieee80211_input.h>
51 #ifdef IEEE80211_SUPPORT_MESH
52 #include <net80211/ieee80211_mesh.h>
53 #endif
54 
55 #include <net/bpf.h>
56 
57 #ifdef INET
58 #include <netinet/in.h>
59 #include <net/ethernet.h>
60 #endif
61 
62 static void
63 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
64 {
65 	int i;
66 
67 	/* Verify the required MIMO bits are set */
68 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
69 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
70 		return;
71 
72 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
73 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
74 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
75 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
76 	}
77 
78 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
79 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
80 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
81 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
82 	}
83 	ni->ni_mimo_chains = rx->c_chain;
84 }
85 
86 int
87 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m)
88 {
89 	struct ieee80211_rx_stats rxs;
90 
91 	/* try to read stats from mbuf */
92 	bzero(&rxs, sizeof(rxs));
93 	if (ieee80211_get_rx_params(m, &rxs) != 0)
94 		return (-1);
95 
96 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
97 	ieee80211_process_mimo(ni, &rxs);
98 
99 	//return ieee80211_input(ni, m, rx->rssi, rx->nf);
100 	return ni->ni_vap->iv_input(ni, m, &rxs, rxs.c_rssi, rxs.c_nf);
101 }
102 
103 int
104 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
105 {
106 	struct ieee80211_rx_stats rx;
107 
108 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
109 	rx.c_nf = nf;
110 	rx.c_rssi = rssi;
111 
112 	if (!ieee80211_add_rx_params(m, &rx))
113 		return (-1);
114 
115 	return ieee80211_input_mimo_all(ic, m);
116 }
117 
118 int
119 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m)
120 {
121 	struct ieee80211vap *vap;
122 	int type = -1;
123 
124 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
125 
126 	/* XXX locking */
127 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
128 		struct ieee80211_node *ni;
129 		struct mbuf *mcopy;
130 
131 		/* NB: could check for IFF_UP but this is cheaper */
132 		if (vap->iv_state == IEEE80211_S_INIT)
133 			continue;
134 		/*
135 		 * WDS vap's only receive directed traffic from the
136 		 * station at the ``far end''.  That traffic should
137 		 * be passed through the AP vap the station is associated
138 		 * to--so don't spam them with mcast frames.
139 		 */
140 		if (vap->iv_opmode == IEEE80211_M_WDS)
141 			continue;
142 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
143 			/*
144 			 * Packet contents are changed by ieee80211_decap
145 			 * so do a deep copy of the packet.
146 			 * NB: tags are copied too.
147 			 */
148 			mcopy = m_dup(m, IEEE80211_M_NOWAIT);
149 			if (mcopy == NULL) {
150 				/* XXX stat+msg */
151 				continue;
152 			}
153 		} else {
154 			mcopy = m;
155 			m = NULL;
156 		}
157 		ni = ieee80211_ref_node(vap->iv_bss);
158 		type = ieee80211_input_mimo(ni, mcopy);
159 		ieee80211_free_node(ni);
160 	}
161 	if (m != NULL)			/* no vaps, reclaim mbuf */
162 		m_freem(m);
163 	return type;
164 }
165 
166 /*
167  * This function reassembles fragments.
168  *
169  * XXX should handle 3 concurrent reassemblies per-spec.
170  */
171 struct mbuf *
172 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace,
173 	int has_decrypted)
174 {
175 	struct ieee80211vap *vap = ni->ni_vap;
176 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
177 	struct ieee80211_frame *lwh;
178 	uint16_t rxseq;
179 	uint8_t fragno;
180 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
181 	struct mbuf *mfrag;
182 
183 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
184 
185 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
186 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
187 
188 	/* Quick way out, if there's nothing to defragment */
189 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
190 		return m;
191 
192 	/* Temporarily set flag to remember if fragment was encrypted. */
193 	/* XXX use a non-packet altering storage for this in the future. */
194 	if (has_decrypted)
195 		wh->i_fc[1] |= IEEE80211_FC1_PROTECTED;
196 
197 	/*
198 	 * Remove frag to insure it doesn't get reaped by timer.
199 	 */
200 	if (ni->ni_table == NULL) {
201 		/*
202 		 * Should never happen.  If the node is orphaned (not in
203 		 * the table) then input packets should not reach here.
204 		 * Otherwise, a concurrent request that yanks the table
205 		 * should be blocked by other interlocking and/or by first
206 		 * shutting the driver down.  Regardless, be defensive
207 		 * here and just bail
208 		 */
209 		/* XXX need msg+stat */
210 		m_freem(m);
211 		return NULL;
212 	}
213 	IEEE80211_NODE_LOCK(ni->ni_table);
214 	mfrag = ni->ni_rxfrag[0];
215 	ni->ni_rxfrag[0] = NULL;
216 	IEEE80211_NODE_UNLOCK(ni->ni_table);
217 
218 	/*
219 	 * Validate new fragment is in order and
220 	 * related to the previous ones.
221 	 */
222 	if (mfrag != NULL) {
223 		uint16_t last_rxseq;
224 
225 		lwh = mtod(mfrag, struct ieee80211_frame *);
226 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
227 		/*
228 		 * NB: check seq # and frag together. Also check that both
229 		 * fragments are plaintext or that both are encrypted.
230 		 */
231 		if (rxseq == last_rxseq+1 &&
232 		    IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) &&
233 		    IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2) &&
234 		    !((wh->i_fc[1] ^ lwh->i_fc[1]) & IEEE80211_FC1_PROTECTED)) {
235 			/* XXX clear MORE_FRAG bit? */
236 			/* track last seqnum and fragno */
237 			*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
238 
239 			m_adj(m, hdrspace);		/* strip header */
240 			m_catpkt(mfrag, m);		/* concatenate */
241 		} else {
242 			/*
243 			 * Unrelated fragment or no space for it,
244 			 * clear current fragments.
245 			 */
246 			m_freem(mfrag);
247 			mfrag = NULL;
248 		}
249 	}
250 
251  	if (mfrag == NULL) {
252 		if (fragno != 0) {		/* !first fragment, discard */
253 			vap->iv_stats.is_rx_defrag++;
254 			IEEE80211_NODE_STAT(ni, rx_defrag);
255 			m_freem(m);
256 			return NULL;
257 		}
258 		mfrag = m;
259 	}
260 	if (more_frag) {			/* more to come, save */
261 		ni->ni_rxfragstamp = ticks;
262 		ni->ni_rxfrag[0] = mfrag;
263 		mfrag = NULL;
264 	}
265 	/* Remember to clear protected flag that was temporarily set. */
266 	if (mfrag != NULL) {
267 		wh = mtod(mfrag, struct ieee80211_frame *);
268 		wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
269 	}
270 	return mfrag;
271 }
272 
273 void
274 ieee80211_deliver_data(struct ieee80211vap *vap,
275 	struct ieee80211_node *ni, struct mbuf *m)
276 {
277 	struct ether_header *eh = mtod(m, struct ether_header *);
278 	struct ifnet *ifp = vap->iv_ifp;
279 
280 	/* clear driver/net80211 flags before passing up */
281 	m->m_flags &= ~(M_MCAST | M_BCAST);
282 	m_clrprotoflags(m);
283 
284 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
285 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
286 	/*
287 	 * Do accounting.
288 	 */
289 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
290 	IEEE80211_NODE_STAT(ni, rx_data);
291 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
292 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
293 		if (ETHER_IS_BROADCAST(eh->ether_dhost))
294 			m->m_flags |= M_BCAST;
295 		else
296 			m->m_flags |= M_MCAST;
297 		IEEE80211_NODE_STAT(ni, rx_mcast);
298 	} else
299 		IEEE80211_NODE_STAT(ni, rx_ucast);
300 	m->m_pkthdr.rcvif = ifp;
301 
302 	if (ni->ni_vlan != 0) {
303 		/* attach vlan tag */
304 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
305 		m->m_flags |= M_VLANTAG;
306 	}
307 	ifp->if_input(ifp, m);
308 }
309 
310 struct mbuf *
311 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen,
312 	uint8_t qos)
313 {
314 	struct ieee80211_qosframe_addr4 wh;
315 	struct ether_header *eh;
316 	struct llc *llc;
317 
318 	KASSERT(hdrlen <= sizeof(wh),
319 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
320 
321 	if (m->m_len < hdrlen + sizeof(*llc) &&
322 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
323 		vap->iv_stats.is_rx_tooshort++;
324 		/* XXX msg */
325 		return NULL;
326 	}
327 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
328 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
329 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
330 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
331 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
332 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
333 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
334 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX)) &&
335 	    /* Do not want to touch A-MSDU frames. */
336 	    !(qos & IEEE80211_QOS_AMSDU)) {
337 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
338 		llc = NULL;
339 	} else {
340 		m_adj(m, hdrlen - sizeof(*eh));
341 	}
342 	eh = mtod(m, struct ether_header *);
343 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
344 	case IEEE80211_FC1_DIR_NODS:
345 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
346 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
347 		break;
348 	case IEEE80211_FC1_DIR_TODS:
349 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
350 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
351 		break;
352 	case IEEE80211_FC1_DIR_FROMDS:
353 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
354 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
355 		break;
356 	case IEEE80211_FC1_DIR_DSTODS:
357 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
358 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
359 		break;
360 	}
361 #ifndef __NO_STRICT_ALIGNMENT
362 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
363 		m = ieee80211_realign(vap, m, sizeof(*eh));
364 		if (m == NULL)
365 			return NULL;
366 	}
367 #endif /* !__NO_STRICT_ALIGNMENT */
368 	if (llc != NULL) {
369 		eh = mtod(m, struct ether_header *);
370 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
371 	}
372 	return m;
373 }
374 
375 /*
376  * Decap a frame encapsulated in a fast-frame/A-MSDU.
377  */
378 struct mbuf *
379 ieee80211_decap1(struct mbuf *m, int *framelen)
380 {
381 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
382 	struct ether_header *eh;
383 	struct llc *llc;
384 	const uint8_t llc_hdr_mac[ETHER_ADDR_LEN] = {
385 		/* MAC address matching the 802.2 LLC header */
386 		LLC_SNAP_LSAP, LLC_SNAP_LSAP, LLC_UI, 0, 0, 0
387 	};
388 
389 	/*
390 	 * The frame has an 802.3 header followed by an 802.2
391 	 * LLC header.  The encapsulated frame length is in the
392 	 * first header type field; save that and overwrite it
393 	 * with the true type field found in the second.  Then
394 	 * copy the 802.3 header up to where it belongs and
395 	 * adjust the mbuf contents to remove the void.
396 	 */
397 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
398 		return NULL;
399 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
400 
401 	/*
402 	 * Detect possible attack where a single 802.11 frame is processed
403 	 * as an A-MSDU frame due to an adversary setting the A-MSDU present
404 	 * bit in the 802.11 QoS header. [FragAttacks]
405 	 */
406 	if (memcmp(eh->ether_dhost, llc_hdr_mac, ETHER_ADDR_LEN) == 0)
407 		return NULL;
408 
409 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
410 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
411 		  + sizeof(struct ether_header) - sizeof(struct llc);
412 	eh->ether_type = llc->llc_un.type_snap.ether_type;
413 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
414 		sizeof(struct ether_header));
415 	m_adj(m, sizeof(struct llc));
416 	return m;
417 #undef FF_LLC_SIZE
418 }
419 
420 /*
421  * Install received rate set information in the node's state block.
422  */
423 int
424 ieee80211_setup_rates(struct ieee80211_node *ni,
425 	const uint8_t *rates, const uint8_t *xrates, int flags)
426 {
427 	struct ieee80211vap *vap = ni->ni_vap;
428 	struct ieee80211_rateset *rs = &ni->ni_rates;
429 
430 	memset(rs, 0, sizeof(*rs));
431 	rs->rs_nrates = rates[1];
432 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
433 	if (xrates != NULL) {
434 		uint8_t nxrates;
435 		/*
436 		 * Tack on 11g extended supported rate element.
437 		 */
438 		nxrates = xrates[1];
439 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
440 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
441 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
442 			    "extended rate set too large; only using "
443 			    "%u of %u rates", nxrates, xrates[1]);
444 			vap->iv_stats.is_rx_rstoobig++;
445 		}
446 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
447 		rs->rs_nrates += nxrates;
448 	}
449 	return ieee80211_fix_rate(ni, rs, flags);
450 }
451 
452 /*
453  * Send a management frame error response to the specified
454  * station.  If ni is associated with the station then use
455  * it; otherwise allocate a temporary node suitable for
456  * transmitting the frame and then free the reference so
457  * it will go away as soon as the frame has been transmitted.
458  */
459 void
460 ieee80211_send_error(struct ieee80211_node *ni,
461 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
462 {
463 	struct ieee80211vap *vap = ni->ni_vap;
464 	int istmp;
465 
466 	if (ni == vap->iv_bss) {
467 		if (vap->iv_state != IEEE80211_S_RUN) {
468 			/*
469 			 * XXX hack until we get rid of this routine.
470 			 * We can be called prior to the vap reaching
471 			 * run state under certain conditions in which
472 			 * case iv_bss->ni_chan will not be setup.
473 			 * Check for this explicitly and and just ignore
474 			 * the request.
475 			 */
476 			return;
477 		}
478 		ni = ieee80211_tmp_node(vap, mac);
479 		if (ni == NULL) {
480 			/* XXX msg */
481 			return;
482 		}
483 		istmp = 1;
484 	} else
485 		istmp = 0;
486 	IEEE80211_SEND_MGMT(ni, subtype, arg);
487 	if (istmp)
488 		ieee80211_free_node(ni);
489 }
490 
491 int
492 ieee80211_alloc_challenge(struct ieee80211_node *ni)
493 {
494 	if (ni->ni_challenge == NULL)
495 		ni->ni_challenge = (uint32_t *)
496 		    IEEE80211_MALLOC(IEEE80211_CHALLENGE_LEN,
497 		      M_80211_NODE, IEEE80211_M_NOWAIT);
498 	if (ni->ni_challenge == NULL) {
499 		IEEE80211_NOTE(ni->ni_vap,
500 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
501 		    "%s", "shared key challenge alloc failed");
502 		/* XXX statistic */
503 	}
504 	return (ni->ni_challenge != NULL);
505 }
506 
507 /*
508  * Parse a Beacon or ProbeResponse frame and return the
509  * useful information in an ieee80211_scanparams structure.
510  * Status is set to 0 if no problems were found; otherwise
511  * a bitmask of IEEE80211_BPARSE_* items is returned that
512  * describes the problems detected.
513  */
514 int
515 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
516 	struct ieee80211_channel *rxchan, struct ieee80211_scanparams *scan)
517 {
518 	struct ieee80211vap *vap = ni->ni_vap;
519 	struct ieee80211com *ic = ni->ni_ic;
520 	struct ieee80211_frame *wh;
521 	uint8_t *frm, *efrm;
522 
523 	wh = mtod(m, struct ieee80211_frame *);
524 	frm = (uint8_t *)&wh[1];
525 	efrm = mtod(m, uint8_t *) + m->m_len;
526 	scan->status = 0;
527 	/*
528 	 * beacon/probe response frame format
529 	 *
530 	 * XXX Update from 802.11-2012 - eg where HT is
531 	 *	[8] time stamp
532 	 *	[2] beacon interval
533 	 *	[2] capability information
534 	 *	[tlv] ssid
535 	 *	[tlv] supported rates
536 	 *	[tlv] country information
537 	 *	[tlv] channel switch announcement (CSA)
538 	 *	[tlv] parameter set (FH/DS)
539 	 *	[tlv] erp information
540 	 *	[tlv] extended supported rates
541 	 *	[tlv] WME
542 	 *	[tlv] WPA or RSN
543 	 *	[tlv] HT capabilities
544 	 *	[tlv] HT information
545 	 *	[tlv] VHT capabilities
546 	 *	[tlv] VHT information
547 	 *	[tlv] Atheros capabilities
548 	 *	[tlv] Mesh ID
549 	 *	[tlv] Mesh Configuration
550 	 */
551 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
552 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
553 	memset(scan, 0, sizeof(*scan));
554 	scan->tstamp  = frm;				frm += 8;
555 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
556 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
557 	scan->bchan = ieee80211_chan2ieee(ic, rxchan);
558 	scan->chan = scan->bchan;
559 	scan->ies = frm;
560 	scan->ies_len = efrm - frm;
561 
562 	while (efrm - frm > 1) {
563 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
564 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
565 		switch (*frm) {
566 		case IEEE80211_ELEMID_SSID:
567 			scan->ssid = frm;
568 			break;
569 		case IEEE80211_ELEMID_RATES:
570 			scan->rates = frm;
571 			break;
572 		case IEEE80211_ELEMID_COUNTRY:
573 			scan->country = frm;
574 			break;
575 		case IEEE80211_ELEMID_CSA:
576 			scan->csa = frm;
577 			break;
578 		case IEEE80211_ELEMID_QUIET:
579 			scan->quiet = frm;
580 			break;
581 		case IEEE80211_ELEMID_FHPARMS:
582 			if (ic->ic_phytype == IEEE80211_T_FH) {
583 				scan->fhdwell = le16dec(&frm[2]);
584 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
585 				scan->fhindex = frm[6];
586 			}
587 			break;
588 		case IEEE80211_ELEMID_DSPARMS:
589 			/*
590 			 * XXX hack this since depending on phytype
591 			 * is problematic for multi-mode devices.
592 			 */
593 			if (ic->ic_phytype != IEEE80211_T_FH)
594 				scan->chan = frm[2];
595 			break;
596 		case IEEE80211_ELEMID_TIM:
597 			/* XXX ATIM? */
598 			scan->tim = frm;
599 			scan->timoff = frm - mtod(m, uint8_t *);
600 			break;
601 		case IEEE80211_ELEMID_IBSSPARMS:
602 		case IEEE80211_ELEMID_CFPARMS:
603 		case IEEE80211_ELEMID_PWRCNSTR:
604 		case IEEE80211_ELEMID_BSSLOAD:
605 		case IEEE80211_ELEMID_APCHANREP:
606 			/* NB: avoid debugging complaints */
607 			break;
608 		case IEEE80211_ELEMID_XRATES:
609 			scan->xrates = frm;
610 			break;
611 		case IEEE80211_ELEMID_ERP:
612 			if (frm[1] != 1) {
613 				IEEE80211_DISCARD_IE(vap,
614 				    IEEE80211_MSG_ELEMID, wh, "ERP",
615 				    "bad len %u", frm[1]);
616 				vap->iv_stats.is_rx_elem_toobig++;
617 				break;
618 			}
619 			scan->erp = frm[2] | 0x100;
620 			break;
621 		case IEEE80211_ELEMID_HTCAP:
622 			scan->htcap = frm;
623 			break;
624 		case IEEE80211_ELEMID_VHT_CAP:
625 			scan->vhtcap = frm;
626 			break;
627 		case IEEE80211_ELEMID_VHT_OPMODE:
628 			scan->vhtopmode = frm;
629 			break;
630 		case IEEE80211_ELEMID_RSN:
631 			scan->rsn = frm;
632 			break;
633 		case IEEE80211_ELEMID_HTINFO:
634 			scan->htinfo = frm;
635 			break;
636 #ifdef IEEE80211_SUPPORT_MESH
637 		case IEEE80211_ELEMID_MESHID:
638 			scan->meshid = frm;
639 			break;
640 		case IEEE80211_ELEMID_MESHCONF:
641 			scan->meshconf = frm;
642 			break;
643 #endif
644 		/* Extended capabilities; nothing handles it for now */
645 		case IEEE80211_ELEMID_EXTCAP:
646 			break;
647 		case IEEE80211_ELEMID_VENDOR:
648 			if (iswpaoui(frm))
649 				scan->wpa = frm;
650 			else if (iswmeparam(frm) || iswmeinfo(frm))
651 				scan->wme = frm;
652 #ifdef IEEE80211_SUPPORT_SUPERG
653 			else if (isatherosoui(frm))
654 				scan->ath = frm;
655 #endif
656 #ifdef IEEE80211_SUPPORT_TDMA
657 			else if (istdmaoui(frm))
658 				scan->tdma = frm;
659 #endif
660 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
661 				/*
662 				 * Accept pre-draft HT ie's if the
663 				 * standard ones have not been seen.
664 				 */
665 				if (ishtcapoui(frm)) {
666 					if (scan->htcap == NULL)
667 						scan->htcap = frm;
668 				} else if (ishtinfooui(frm)) {
669 					if (scan->htinfo == NULL)
670 						scan->htcap = frm;
671 				}
672 			}
673 			break;
674 		default:
675 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
676 			    wh, "unhandled",
677 			    "id %u, len %u", *frm, frm[1]);
678 			vap->iv_stats.is_rx_elem_unknown++;
679 			break;
680 		}
681 		frm += frm[1] + 2;
682 	}
683 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
684 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
685 	if (scan->rates != NULL && scan->xrates != NULL) {
686 		/*
687 		 * NB: don't process XRATES if RATES is missing.  This
688 		 * avoids a potential null ptr deref and should be ok
689 		 * as the return code will already note RATES is missing
690 		 * (so callers shouldn't otherwise process the frame).
691 		 */
692 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
693 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
694 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
695 	}
696 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
697 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
698 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
699 		/*
700 		 * Frame was received on a channel different from the
701 		 * one indicated in the DS params element id;
702 		 * silently discard it.
703 		 *
704 		 * NB: this can happen due to signal leakage.
705 		 *     But we should take it for FH phy because
706 		 *     the rssi value should be correct even for
707 		 *     different hop pattern in FH.
708 		 */
709 		IEEE80211_DISCARD(vap,
710 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
711 		    wh, NULL, "for off-channel %u (bchan=%u)",
712 		    scan->chan, scan->bchan);
713 		vap->iv_stats.is_rx_chanmismatch++;
714 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
715 	}
716 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
717 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
718 		IEEE80211_DISCARD(vap,
719 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
720 		    wh, NULL, "bogus beacon interval (%d TU)",
721 		    (int) scan->bintval);
722 		vap->iv_stats.is_rx_badbintval++;
723 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
724 	}
725 	if (scan->country != NULL) {
726 		/*
727 		 * Validate we have at least enough data to extract
728 		 * the country code.  Not sure if we should return an
729 		 * error instead of discarding the IE; consider this
730 		 * being lenient as we don't depend on the data for
731 		 * correct operation.
732 		 */
733 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
734 		    scan->country = NULL);
735 	}
736 	if (scan->csa != NULL) {
737 		/*
738 		 * Validate Channel Switch Announcement; this must
739 		 * be the correct length or we toss the frame.
740 		 */
741 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
742 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
743 	}
744 #ifdef IEEE80211_SUPPORT_MESH
745 	if (scan->meshid != NULL) {
746 		IEEE80211_VERIFY_ELEMENT(scan->meshid, IEEE80211_MESHID_LEN,
747 		    scan->status |= IEEE80211_BPARSE_MESHID_INVALID);
748 	}
749 #endif
750 	/*
751 	 * Process HT ie's.  This is complicated by our
752 	 * accepting both the standard ie's and the pre-draft
753 	 * vendor OUI ie's that some vendors still use/require.
754 	 */
755 	if (scan->htcap != NULL) {
756 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
757 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
758 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
759 			 sizeof(struct ieee80211_ie_htcap)-2,
760 		     scan->htcap = NULL);
761 	}
762 	if (scan->htinfo != NULL) {
763 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
764 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
765 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
766 			 sizeof(struct ieee80211_ie_htinfo)-2,
767 		     scan->htinfo = NULL);
768 	}
769 
770 	/* Process VHT IEs */
771 	if (scan->vhtcap != NULL) {
772 		IEEE80211_VERIFY_LENGTH(scan->vhtcap[1],
773 		    sizeof(struct ieee80211_ie_vhtcap) - 2,
774 		    scan->vhtcap = NULL);
775 	}
776 	if (scan->vhtopmode != NULL) {
777 		IEEE80211_VERIFY_LENGTH(scan->vhtopmode[1],
778 		    sizeof(struct ieee80211_ie_vht_operation) - 2,
779 		    scan->vhtopmode = NULL);
780 	}
781 
782 	return scan->status;
783 }
784 
785 /*
786  * Parse an Action frame.  Return 0 on success, non-zero on failure.
787  */
788 int
789 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
790 {
791 	struct ieee80211vap *vap = ni->ni_vap;
792 	const struct ieee80211_action *ia;
793 	struct ieee80211_frame *wh;
794 	uint8_t *frm, *efrm;
795 
796 	/*
797 	 * action frame format:
798 	 *	[1] category
799 	 *	[1] action
800 	 *	[tlv] parameters
801 	 */
802 	wh = mtod(m, struct ieee80211_frame *);
803 	frm = (u_int8_t *)&wh[1];
804 	efrm = mtod(m, u_int8_t *) + m->m_len;
805 	IEEE80211_VERIFY_LENGTH(efrm - frm,
806 		sizeof(struct ieee80211_action), return EINVAL);
807 	ia = (const struct ieee80211_action *) frm;
808 
809 	vap->iv_stats.is_rx_action++;
810 	IEEE80211_NODE_STAT(ni, rx_action);
811 
812 	/* verify frame payloads but defer processing */
813 	switch (ia->ia_category) {
814 	case IEEE80211_ACTION_CAT_BA:
815 		switch (ia->ia_action) {
816 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
817 			IEEE80211_VERIFY_LENGTH(efrm - frm,
818 			    sizeof(struct ieee80211_action_ba_addbarequest),
819 			    return EINVAL);
820 			break;
821 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
822 			IEEE80211_VERIFY_LENGTH(efrm - frm,
823 			    sizeof(struct ieee80211_action_ba_addbaresponse),
824 			    return EINVAL);
825 			break;
826 		case IEEE80211_ACTION_BA_DELBA:
827 			IEEE80211_VERIFY_LENGTH(efrm - frm,
828 			    sizeof(struct ieee80211_action_ba_delba),
829 			    return EINVAL);
830 			break;
831 		}
832 		break;
833 	case IEEE80211_ACTION_CAT_HT:
834 		switch (ia->ia_action) {
835 		case IEEE80211_ACTION_HT_TXCHWIDTH:
836 			IEEE80211_VERIFY_LENGTH(efrm - frm,
837 			    sizeof(struct ieee80211_action_ht_txchwidth),
838 			    return EINVAL);
839 			break;
840 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
841 			IEEE80211_VERIFY_LENGTH(efrm - frm,
842 			    sizeof(struct ieee80211_action_ht_mimopowersave),
843 			    return EINVAL);
844 			break;
845 		}
846 		break;
847 #ifdef IEEE80211_SUPPORT_MESH
848 	case IEEE80211_ACTION_CAT_MESH:
849 		switch (ia->ia_action) {
850 		case IEEE80211_ACTION_MESH_LMETRIC:
851 			/*
852 			 * XXX: verification is true only if we are using
853 			 * Airtime link metric (default)
854 			 */
855 			IEEE80211_VERIFY_LENGTH(efrm - frm,
856 			    sizeof(struct ieee80211_meshlmetric_ie),
857 			    return EINVAL);
858 			break;
859 		case IEEE80211_ACTION_MESH_HWMP:
860 			/* verify something */
861 			break;
862 		case IEEE80211_ACTION_MESH_GANN:
863 			IEEE80211_VERIFY_LENGTH(efrm - frm,
864 			    sizeof(struct ieee80211_meshgann_ie),
865 			    return EINVAL);
866 			break;
867 		case IEEE80211_ACTION_MESH_CC:
868 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
869 		case IEEE80211_ACTION_MESH_MCCA_SREP:
870 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
871 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
872 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
873 		case IEEE80211_ACTION_MESH_TBTT_REQ:
874 		case IEEE80211_ACTION_MESH_TBTT_RES:
875 			/* reject these early on, not implemented */
876 			IEEE80211_DISCARD(vap,
877 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
878 			    wh, NULL, "not implemented yet, act=0x%02X",
879 			    ia->ia_action);
880 			return EINVAL;
881 		}
882 		break;
883 	case IEEE80211_ACTION_CAT_SELF_PROT:
884 		/* If TA or RA group address discard silently */
885 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
886 			IEEE80211_IS_MULTICAST(wh->i_addr2))
887 			return EINVAL;
888 		/*
889 		 * XXX: Should we verify complete length now or it is
890 		 * to varying in sizes?
891 		 */
892 		switch (ia->ia_action) {
893 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
894 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
895 			/* is not a peering candidate (yet) */
896 			if (ni == vap->iv_bss)
897 				return EINVAL;
898 			break;
899 		}
900 		break;
901 #endif
902 	case IEEE80211_ACTION_CAT_VHT:
903 		printf("%s: TODO: VHT handling!\n", __func__);
904 		break;
905 	}
906 	return 0;
907 }
908 
909 #ifdef IEEE80211_DEBUG
910 /*
911  * Debugging support.
912  */
913 void
914 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
915 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
916 {
917 	printf("[%s] discard %s frame, ssid mismatch: ",
918 		ether_sprintf(mac), tag);
919 	ieee80211_print_essid(ssid + 2, ssid[1]);
920 	printf("\n");
921 }
922 
923 /*
924  * Return the bssid of a frame.
925  */
926 static const uint8_t *
927 ieee80211_getbssid(const struct ieee80211vap *vap,
928 	const struct ieee80211_frame *wh)
929 {
930 	if (vap->iv_opmode == IEEE80211_M_STA)
931 		return wh->i_addr2;
932 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
933 		return wh->i_addr1;
934 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
935 		return wh->i_addr1;
936 	return wh->i_addr3;
937 }
938 
939 #include <machine/stdarg.h>
940 
941 void
942 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
943 {
944 	char buf[256];		/* XXX */
945 	va_list ap;
946 	int len;
947 
948 	va_start(ap, fmt);
949 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
950 	va_end(ap);
951 
952 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
953 
954 	if (len >= sizeof(buf))
955 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
956 }
957 
958 void
959 ieee80211_note_frame(const struct ieee80211vap *vap,
960 	const struct ieee80211_frame *wh,
961 	const char *fmt, ...)
962 {
963 	char buf[256];		/* XXX */
964 	va_list ap;
965 	int len;
966 
967 	va_start(ap, fmt);
968 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
969 	va_end(ap);
970 	if_printf(vap->iv_ifp, "[%s] %s\n",
971 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
972 
973 	if (len >= sizeof(buf))
974 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
975 }
976 
977 void
978 ieee80211_note_mac(const struct ieee80211vap *vap,
979 	const uint8_t mac[IEEE80211_ADDR_LEN],
980 	const char *fmt, ...)
981 {
982 	char buf[256];		/* XXX */
983 	va_list ap;
984 	int len;
985 
986 	va_start(ap, fmt);
987 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
988 	va_end(ap);
989 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
990 
991 	if (len >= sizeof(buf))
992 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
993 }
994 
995 void
996 ieee80211_discard_frame(const struct ieee80211vap *vap,
997 	const struct ieee80211_frame *wh,
998 	const char *type, const char *fmt, ...)
999 {
1000 	char buf[256];		/* XXX */
1001 	va_list ap;
1002 	int len;
1003 
1004 	va_start(ap, fmt);
1005 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1006 	va_end(ap);
1007 
1008 	if_printf(vap->iv_ifp, "[%s] discard %s frame, %s\n",
1009 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1010 	    type != NULL ? type : ieee80211_mgt_subtype_name(wh->i_fc[0]),
1011 	    buf);
1012 
1013 	if (len >= sizeof(buf))
1014 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1015 }
1016 
1017 void
1018 ieee80211_discard_ie(const struct ieee80211vap *vap,
1019 	const struct ieee80211_frame *wh,
1020 	const char *type, const char *fmt, ...)
1021 {
1022 	char buf[256];		/* XXX */
1023 	va_list ap;
1024 	int len;
1025 
1026 	va_start(ap, fmt);
1027 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1028 	va_end(ap);
1029 
1030 	if_printf(vap->iv_ifp, "[%s] discard%s%s information element, %s\n",
1031 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1032 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1033 
1034 	if (len >= sizeof(buf))
1035 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1036 }
1037 
1038 void
1039 ieee80211_discard_mac(const struct ieee80211vap *vap,
1040 	const uint8_t mac[IEEE80211_ADDR_LEN],
1041 	const char *type, const char *fmt, ...)
1042 {
1043 	char buf[256];		/* XXX */
1044 	va_list ap;
1045 	int len;
1046 
1047 	va_start(ap, fmt);
1048 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1049 	va_end(ap);
1050 
1051 	if_printf(vap->iv_ifp, "[%s] discard%s%s frame, %s\n",
1052 	    ether_sprintf(mac),
1053 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1054 
1055 	if (len >= sizeof(buf))
1056 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1057 }
1058 #endif /* IEEE80211_DEBUG */
1059