xref: /freebsd/sys/net80211/ieee80211_input.c (revision 43a5ec4eb41567cc92586503212743d89686d78f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
31 
32 #include "opt_wlan.h"
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/mbuf.h>
37 #include <sys/malloc.h>
38 #include <sys/endian.h>
39 #include <sys/kernel.h>
40 
41 #include <sys/socket.h>
42 
43 #include <net/ethernet.h>
44 #include <net/if.h>
45 #include <net/if_var.h>
46 #include <net/if_llc.h>
47 #include <net/if_media.h>
48 #include <net/if_vlan_var.h>
49 
50 #include <net80211/ieee80211_var.h>
51 #include <net80211/ieee80211_input.h>
52 #ifdef IEEE80211_SUPPORT_MESH
53 #include <net80211/ieee80211_mesh.h>
54 #endif
55 
56 #include <net/bpf.h>
57 
58 #ifdef INET
59 #include <netinet/in.h>
60 #include <net/ethernet.h>
61 #endif
62 
63 static void
64 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
65 {
66 	int i;
67 
68 	/* Verify the required MIMO bits are set */
69 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
70 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
71 		return;
72 
73 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
74 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
75 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
76 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
77 	}
78 
79 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
80 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
81 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
82 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
83 	}
84 	ni->ni_mimo_chains = rx->c_chain;
85 }
86 
87 int
88 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m)
89 {
90 	struct ieee80211_rx_stats rxs;
91 
92 	/* try to read stats from mbuf */
93 	bzero(&rxs, sizeof(rxs));
94 	if (ieee80211_get_rx_params(m, &rxs) != 0)
95 		return (-1);
96 
97 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
98 	ieee80211_process_mimo(ni, &rxs);
99 
100 	//return ieee80211_input(ni, m, rx->rssi, rx->nf);
101 	return ni->ni_vap->iv_input(ni, m, &rxs, rxs.c_rssi, rxs.c_nf);
102 }
103 
104 int
105 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
106 {
107 	struct ieee80211_rx_stats rx;
108 
109 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
110 	rx.c_nf = nf;
111 	rx.c_rssi = rssi;
112 
113 	if (!ieee80211_add_rx_params(m, &rx))
114 		return (-1);
115 
116 	return ieee80211_input_mimo_all(ic, m);
117 }
118 
119 int
120 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m)
121 {
122 	struct ieee80211vap *vap;
123 	int type = -1;
124 
125 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
126 
127 	/* XXX locking */
128 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
129 		struct ieee80211_node *ni;
130 		struct mbuf *mcopy;
131 
132 		/* NB: could check for IFF_UP but this is cheaper */
133 		if (vap->iv_state == IEEE80211_S_INIT)
134 			continue;
135 		/*
136 		 * WDS vap's only receive directed traffic from the
137 		 * station at the ``far end''.  That traffic should
138 		 * be passed through the AP vap the station is associated
139 		 * to--so don't spam them with mcast frames.
140 		 */
141 		if (vap->iv_opmode == IEEE80211_M_WDS)
142 			continue;
143 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
144 			/*
145 			 * Packet contents are changed by ieee80211_decap
146 			 * so do a deep copy of the packet.
147 			 * NB: tags are copied too.
148 			 */
149 			mcopy = m_dup(m, M_NOWAIT);
150 			if (mcopy == NULL) {
151 				/* XXX stat+msg */
152 				continue;
153 			}
154 		} else {
155 			mcopy = m;
156 			m = NULL;
157 		}
158 		ni = ieee80211_ref_node(vap->iv_bss);
159 		type = ieee80211_input_mimo(ni, mcopy);
160 		ieee80211_free_node(ni);
161 	}
162 	if (m != NULL)			/* no vaps, reclaim mbuf */
163 		m_freem(m);
164 	return type;
165 }
166 
167 /*
168  * This function reassembles fragments.
169  *
170  * XXX should handle 3 concurrent reassemblies per-spec.
171  */
172 struct mbuf *
173 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace,
174 	int has_decrypted)
175 {
176 	struct ieee80211vap *vap = ni->ni_vap;
177 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
178 	struct ieee80211_frame *lwh;
179 	uint16_t rxseq;
180 	uint8_t fragno;
181 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
182 	struct mbuf *mfrag;
183 
184 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
185 
186 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
187 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
188 
189 	/* Quick way out, if there's nothing to defragment */
190 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
191 		return m;
192 
193 	/* Temporarily set flag to remember if fragment was encrypted. */
194 	/* XXX use a non-packet altering storage for this in the future. */
195 	if (has_decrypted)
196 		wh->i_fc[1] |= IEEE80211_FC1_PROTECTED;
197 
198 	/*
199 	 * Remove frag to insure it doesn't get reaped by timer.
200 	 */
201 	if (ni->ni_table == NULL) {
202 		/*
203 		 * Should never happen.  If the node is orphaned (not in
204 		 * the table) then input packets should not reach here.
205 		 * Otherwise, a concurrent request that yanks the table
206 		 * should be blocked by other interlocking and/or by first
207 		 * shutting the driver down.  Regardless, be defensive
208 		 * here and just bail
209 		 */
210 		/* XXX need msg+stat */
211 		m_freem(m);
212 		return NULL;
213 	}
214 	IEEE80211_NODE_LOCK(ni->ni_table);
215 	mfrag = ni->ni_rxfrag[0];
216 	ni->ni_rxfrag[0] = NULL;
217 	IEEE80211_NODE_UNLOCK(ni->ni_table);
218 
219 	/*
220 	 * Validate new fragment is in order and
221 	 * related to the previous ones.
222 	 */
223 	if (mfrag != NULL) {
224 		uint16_t last_rxseq;
225 
226 		lwh = mtod(mfrag, struct ieee80211_frame *);
227 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
228 		/*
229 		 * NB: check seq # and frag together. Also check that both
230 		 * fragments are plaintext or that both are encrypted.
231 		 */
232 		if (rxseq == last_rxseq+1 &&
233 		    IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) &&
234 		    IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2) &&
235 		    !((wh->i_fc[1] ^ lwh->i_fc[1]) & IEEE80211_FC1_PROTECTED)) {
236 			/* XXX clear MORE_FRAG bit? */
237 			/* track last seqnum and fragno */
238 			*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
239 
240 			m_adj(m, hdrspace);		/* strip header */
241 			m_catpkt(mfrag, m);		/* concatenate */
242 		} else {
243 			/*
244 			 * Unrelated fragment or no space for it,
245 			 * clear current fragments.
246 			 */
247 			m_freem(mfrag);
248 			mfrag = NULL;
249 		}
250 	}
251 
252  	if (mfrag == NULL) {
253 		if (fragno != 0) {		/* !first fragment, discard */
254 			vap->iv_stats.is_rx_defrag++;
255 			IEEE80211_NODE_STAT(ni, rx_defrag);
256 			m_freem(m);
257 			return NULL;
258 		}
259 		mfrag = m;
260 	}
261 	if (more_frag) {			/* more to come, save */
262 		ni->ni_rxfragstamp = ticks;
263 		ni->ni_rxfrag[0] = mfrag;
264 		mfrag = NULL;
265 	}
266 	/* Remember to clear protected flag that was temporarily set. */
267 	if (mfrag != NULL) {
268 		wh = mtod(mfrag, struct ieee80211_frame *);
269 		wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
270 	}
271 	return mfrag;
272 }
273 
274 void
275 ieee80211_deliver_data(struct ieee80211vap *vap,
276 	struct ieee80211_node *ni, struct mbuf *m)
277 {
278 	struct ether_header *eh = mtod(m, struct ether_header *);
279 	struct ifnet *ifp = vap->iv_ifp;
280 
281 	/* clear driver/net80211 flags before passing up */
282 	m->m_flags &= ~(M_MCAST | M_BCAST);
283 	m_clrprotoflags(m);
284 
285 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
286 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
287 	/*
288 	 * Do accounting.
289 	 */
290 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
291 	IEEE80211_NODE_STAT(ni, rx_data);
292 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
293 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
294 		if (ETHER_IS_BROADCAST(eh->ether_dhost))
295 			m->m_flags |= M_BCAST;
296 		else
297 			m->m_flags |= M_MCAST;
298 		IEEE80211_NODE_STAT(ni, rx_mcast);
299 	} else
300 		IEEE80211_NODE_STAT(ni, rx_ucast);
301 	m->m_pkthdr.rcvif = ifp;
302 
303 	if (ni->ni_vlan != 0) {
304 		/* attach vlan tag */
305 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
306 		m->m_flags |= M_VLANTAG;
307 	}
308 	ifp->if_input(ifp, m);
309 }
310 
311 struct mbuf *
312 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen,
313 	uint8_t qos)
314 {
315 	struct ieee80211_qosframe_addr4 wh;
316 	struct ether_header *eh;
317 	struct llc *llc;
318 
319 	KASSERT(hdrlen <= sizeof(wh),
320 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
321 
322 	if (m->m_len < hdrlen + sizeof(*llc) &&
323 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
324 		vap->iv_stats.is_rx_tooshort++;
325 		/* XXX msg */
326 		return NULL;
327 	}
328 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
329 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
330 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
331 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
332 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
333 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
334 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
335 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX)) &&
336 	    /* Do not want to touch A-MSDU frames. */
337 	    !(qos & IEEE80211_QOS_AMSDU)) {
338 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
339 		llc = NULL;
340 	} else {
341 		m_adj(m, hdrlen - sizeof(*eh));
342 	}
343 	eh = mtod(m, struct ether_header *);
344 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
345 	case IEEE80211_FC1_DIR_NODS:
346 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
347 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
348 		break;
349 	case IEEE80211_FC1_DIR_TODS:
350 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
351 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
352 		break;
353 	case IEEE80211_FC1_DIR_FROMDS:
354 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
355 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
356 		break;
357 	case IEEE80211_FC1_DIR_DSTODS:
358 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
359 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
360 		break;
361 	}
362 #ifndef __NO_STRICT_ALIGNMENT
363 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
364 		m = ieee80211_realign(vap, m, sizeof(*eh));
365 		if (m == NULL)
366 			return NULL;
367 	}
368 #endif /* !__NO_STRICT_ALIGNMENT */
369 	if (llc != NULL) {
370 		eh = mtod(m, struct ether_header *);
371 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
372 	}
373 	return m;
374 }
375 
376 /*
377  * Decap a frame encapsulated in a fast-frame/A-MSDU.
378  */
379 struct mbuf *
380 ieee80211_decap1(struct mbuf *m, int *framelen)
381 {
382 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
383 	struct ether_header *eh;
384 	struct llc *llc;
385 	const uint8_t llc_hdr_mac[ETHER_ADDR_LEN] = {
386 		/* MAC address matching the 802.2 LLC header */
387 		LLC_SNAP_LSAP, LLC_SNAP_LSAP, LLC_UI, 0, 0, 0
388 	};
389 
390 	/*
391 	 * The frame has an 802.3 header followed by an 802.2
392 	 * LLC header.  The encapsulated frame length is in the
393 	 * first header type field; save that and overwrite it
394 	 * with the true type field found in the second.  Then
395 	 * copy the 802.3 header up to where it belongs and
396 	 * adjust the mbuf contents to remove the void.
397 	 */
398 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
399 		return NULL;
400 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
401 
402 	/*
403 	 * Detect possible attack where a single 802.11 frame is processed
404 	 * as an A-MSDU frame due to an adversary setting the A-MSDU present
405 	 * bit in the 802.11 QoS header. [FragAttacks]
406 	 */
407 	if (memcmp(eh->ether_dhost, llc_hdr_mac, ETHER_ADDR_LEN) == 0)
408 		return NULL;
409 
410 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
411 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
412 		  + sizeof(struct ether_header) - sizeof(struct llc);
413 	eh->ether_type = llc->llc_un.type_snap.ether_type;
414 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
415 		sizeof(struct ether_header));
416 	m_adj(m, sizeof(struct llc));
417 	return m;
418 #undef FF_LLC_SIZE
419 }
420 
421 /*
422  * Install received rate set information in the node's state block.
423  */
424 int
425 ieee80211_setup_rates(struct ieee80211_node *ni,
426 	const uint8_t *rates, const uint8_t *xrates, int flags)
427 {
428 	struct ieee80211vap *vap = ni->ni_vap;
429 	struct ieee80211_rateset *rs = &ni->ni_rates;
430 
431 	memset(rs, 0, sizeof(*rs));
432 	rs->rs_nrates = rates[1];
433 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
434 	if (xrates != NULL) {
435 		uint8_t nxrates;
436 		/*
437 		 * Tack on 11g extended supported rate element.
438 		 */
439 		nxrates = xrates[1];
440 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
441 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
442 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
443 			    "extended rate set too large; only using "
444 			    "%u of %u rates", nxrates, xrates[1]);
445 			vap->iv_stats.is_rx_rstoobig++;
446 		}
447 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
448 		rs->rs_nrates += nxrates;
449 	}
450 	return ieee80211_fix_rate(ni, rs, flags);
451 }
452 
453 /*
454  * Send a management frame error response to the specified
455  * station.  If ni is associated with the station then use
456  * it; otherwise allocate a temporary node suitable for
457  * transmitting the frame and then free the reference so
458  * it will go away as soon as the frame has been transmitted.
459  */
460 void
461 ieee80211_send_error(struct ieee80211_node *ni,
462 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
463 {
464 	struct ieee80211vap *vap = ni->ni_vap;
465 	int istmp;
466 
467 	if (ni == vap->iv_bss) {
468 		if (vap->iv_state != IEEE80211_S_RUN) {
469 			/*
470 			 * XXX hack until we get rid of this routine.
471 			 * We can be called prior to the vap reaching
472 			 * run state under certain conditions in which
473 			 * case iv_bss->ni_chan will not be setup.
474 			 * Check for this explicitly and and just ignore
475 			 * the request.
476 			 */
477 			return;
478 		}
479 		ni = ieee80211_tmp_node(vap, mac);
480 		if (ni == NULL) {
481 			/* XXX msg */
482 			return;
483 		}
484 		istmp = 1;
485 	} else
486 		istmp = 0;
487 	IEEE80211_SEND_MGMT(ni, subtype, arg);
488 	if (istmp)
489 		ieee80211_free_node(ni);
490 }
491 
492 int
493 ieee80211_alloc_challenge(struct ieee80211_node *ni)
494 {
495 	if (ni->ni_challenge == NULL)
496 		ni->ni_challenge = (uint32_t *)
497 		    IEEE80211_MALLOC(IEEE80211_CHALLENGE_LEN,
498 		      M_80211_NODE, IEEE80211_M_NOWAIT);
499 	if (ni->ni_challenge == NULL) {
500 		IEEE80211_NOTE(ni->ni_vap,
501 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
502 		    "%s", "shared key challenge alloc failed");
503 		/* XXX statistic */
504 	}
505 	return (ni->ni_challenge != NULL);
506 }
507 
508 /*
509  * Parse a Beacon or ProbeResponse frame and return the
510  * useful information in an ieee80211_scanparams structure.
511  * Status is set to 0 if no problems were found; otherwise
512  * a bitmask of IEEE80211_BPARSE_* items is returned that
513  * describes the problems detected.
514  */
515 int
516 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
517 	struct ieee80211_channel *rxchan, struct ieee80211_scanparams *scan)
518 {
519 	struct ieee80211vap *vap = ni->ni_vap;
520 	struct ieee80211com *ic = ni->ni_ic;
521 	struct ieee80211_frame *wh;
522 	uint8_t *frm, *efrm;
523 
524 	wh = mtod(m, struct ieee80211_frame *);
525 	frm = (uint8_t *)&wh[1];
526 	efrm = mtod(m, uint8_t *) + m->m_len;
527 	scan->status = 0;
528 	/*
529 	 * beacon/probe response frame format
530 	 *
531 	 * XXX Update from 802.11-2012 - eg where HT is
532 	 *	[8] time stamp
533 	 *	[2] beacon interval
534 	 *	[2] capability information
535 	 *	[tlv] ssid
536 	 *	[tlv] supported rates
537 	 *	[tlv] country information
538 	 *	[tlv] channel switch announcement (CSA)
539 	 *	[tlv] parameter set (FH/DS)
540 	 *	[tlv] erp information
541 	 *	[tlv] extended supported rates
542 	 *	[tlv] WME
543 	 *	[tlv] WPA or RSN
544 	 *	[tlv] HT capabilities
545 	 *	[tlv] HT information
546 	 *	[tlv] VHT capabilities
547 	 *	[tlv] VHT information
548 	 *	[tlv] Atheros capabilities
549 	 *	[tlv] Mesh ID
550 	 *	[tlv] Mesh Configuration
551 	 */
552 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
553 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
554 	memset(scan, 0, sizeof(*scan));
555 	scan->tstamp  = frm;				frm += 8;
556 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
557 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
558 	scan->bchan = ieee80211_chan2ieee(ic, rxchan);
559 	scan->chan = scan->bchan;
560 	scan->ies = frm;
561 	scan->ies_len = efrm - frm;
562 
563 	while (efrm - frm > 1) {
564 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
565 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
566 		switch (*frm) {
567 		case IEEE80211_ELEMID_SSID:
568 			scan->ssid = frm;
569 			break;
570 		case IEEE80211_ELEMID_RATES:
571 			scan->rates = frm;
572 			break;
573 		case IEEE80211_ELEMID_COUNTRY:
574 			scan->country = frm;
575 			break;
576 		case IEEE80211_ELEMID_CSA:
577 			scan->csa = frm;
578 			break;
579 		case IEEE80211_ELEMID_QUIET:
580 			scan->quiet = frm;
581 			break;
582 		case IEEE80211_ELEMID_FHPARMS:
583 			if (ic->ic_phytype == IEEE80211_T_FH) {
584 				scan->fhdwell = le16dec(&frm[2]);
585 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
586 				scan->fhindex = frm[6];
587 			}
588 			break;
589 		case IEEE80211_ELEMID_DSPARMS:
590 			/*
591 			 * XXX hack this since depending on phytype
592 			 * is problematic for multi-mode devices.
593 			 */
594 			if (ic->ic_phytype != IEEE80211_T_FH)
595 				scan->chan = frm[2];
596 			break;
597 		case IEEE80211_ELEMID_TIM:
598 			/* XXX ATIM? */
599 			scan->tim = frm;
600 			scan->timoff = frm - mtod(m, uint8_t *);
601 			break;
602 		case IEEE80211_ELEMID_IBSSPARMS:
603 		case IEEE80211_ELEMID_CFPARMS:
604 		case IEEE80211_ELEMID_PWRCNSTR:
605 		case IEEE80211_ELEMID_BSSLOAD:
606 		case IEEE80211_ELEMID_APCHANREP:
607 			/* NB: avoid debugging complaints */
608 			break;
609 		case IEEE80211_ELEMID_XRATES:
610 			scan->xrates = frm;
611 			break;
612 		case IEEE80211_ELEMID_ERP:
613 			if (frm[1] != 1) {
614 				IEEE80211_DISCARD_IE(vap,
615 				    IEEE80211_MSG_ELEMID, wh, "ERP",
616 				    "bad len %u", frm[1]);
617 				vap->iv_stats.is_rx_elem_toobig++;
618 				break;
619 			}
620 			scan->erp = frm[2] | 0x100;
621 			break;
622 		case IEEE80211_ELEMID_HTCAP:
623 			scan->htcap = frm;
624 			break;
625 		case IEEE80211_ELEMID_VHT_CAP:
626 			scan->vhtcap = frm;
627 			break;
628 		case IEEE80211_ELEMID_VHT_OPMODE:
629 			scan->vhtopmode = frm;
630 			break;
631 		case IEEE80211_ELEMID_RSN:
632 			scan->rsn = frm;
633 			break;
634 		case IEEE80211_ELEMID_HTINFO:
635 			scan->htinfo = frm;
636 			break;
637 #ifdef IEEE80211_SUPPORT_MESH
638 		case IEEE80211_ELEMID_MESHID:
639 			scan->meshid = frm;
640 			break;
641 		case IEEE80211_ELEMID_MESHCONF:
642 			scan->meshconf = frm;
643 			break;
644 #endif
645 		/* Extended capabilities; nothing handles it for now */
646 		case IEEE80211_ELEMID_EXTCAP:
647 			break;
648 		case IEEE80211_ELEMID_VENDOR:
649 			if (iswpaoui(frm))
650 				scan->wpa = frm;
651 			else if (iswmeparam(frm) || iswmeinfo(frm))
652 				scan->wme = frm;
653 #ifdef IEEE80211_SUPPORT_SUPERG
654 			else if (isatherosoui(frm))
655 				scan->ath = frm;
656 #endif
657 #ifdef IEEE80211_SUPPORT_TDMA
658 			else if (istdmaoui(frm))
659 				scan->tdma = frm;
660 #endif
661 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
662 				/*
663 				 * Accept pre-draft HT ie's if the
664 				 * standard ones have not been seen.
665 				 */
666 				if (ishtcapoui(frm)) {
667 					if (scan->htcap == NULL)
668 						scan->htcap = frm;
669 				} else if (ishtinfooui(frm)) {
670 					if (scan->htinfo == NULL)
671 						scan->htcap = frm;
672 				}
673 			}
674 			break;
675 		default:
676 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
677 			    wh, "unhandled",
678 			    "id %u, len %u", *frm, frm[1]);
679 			vap->iv_stats.is_rx_elem_unknown++;
680 			break;
681 		}
682 		frm += frm[1] + 2;
683 	}
684 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
685 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
686 	if (scan->rates != NULL && scan->xrates != NULL) {
687 		/*
688 		 * NB: don't process XRATES if RATES is missing.  This
689 		 * avoids a potential null ptr deref and should be ok
690 		 * as the return code will already note RATES is missing
691 		 * (so callers shouldn't otherwise process the frame).
692 		 */
693 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
694 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
695 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
696 	}
697 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
698 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
699 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
700 		/*
701 		 * Frame was received on a channel different from the
702 		 * one indicated in the DS params element id;
703 		 * silently discard it.
704 		 *
705 		 * NB: this can happen due to signal leakage.
706 		 *     But we should take it for FH phy because
707 		 *     the rssi value should be correct even for
708 		 *     different hop pattern in FH.
709 		 */
710 		IEEE80211_DISCARD(vap,
711 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
712 		    wh, NULL, "for off-channel %u (bchan=%u)",
713 		    scan->chan, scan->bchan);
714 		vap->iv_stats.is_rx_chanmismatch++;
715 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
716 	}
717 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
718 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
719 		IEEE80211_DISCARD(vap,
720 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
721 		    wh, NULL, "bogus beacon interval (%d TU)",
722 		    (int) scan->bintval);
723 		vap->iv_stats.is_rx_badbintval++;
724 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
725 	}
726 	if (scan->country != NULL) {
727 		/*
728 		 * Validate we have at least enough data to extract
729 		 * the country code.  Not sure if we should return an
730 		 * error instead of discarding the IE; consider this
731 		 * being lenient as we don't depend on the data for
732 		 * correct operation.
733 		 */
734 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
735 		    scan->country = NULL);
736 	}
737 	if (scan->csa != NULL) {
738 		/*
739 		 * Validate Channel Switch Announcement; this must
740 		 * be the correct length or we toss the frame.
741 		 */
742 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
743 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
744 	}
745 	/*
746 	 * Process HT ie's.  This is complicated by our
747 	 * accepting both the standard ie's and the pre-draft
748 	 * vendor OUI ie's that some vendors still use/require.
749 	 */
750 	if (scan->htcap != NULL) {
751 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
752 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
753 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
754 			 sizeof(struct ieee80211_ie_htcap)-2,
755 		     scan->htcap = NULL);
756 	}
757 	if (scan->htinfo != NULL) {
758 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
759 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
760 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
761 			 sizeof(struct ieee80211_ie_htinfo)-2,
762 		     scan->htinfo = NULL);
763 	}
764 
765 	/* Process VHT IEs */
766 	if (scan->vhtcap != NULL) {
767 		IEEE80211_VERIFY_LENGTH(scan->vhtcap[1],
768 		    sizeof(struct ieee80211_ie_vhtcap) - 2,
769 		    scan->vhtcap = NULL);
770 	}
771 	if (scan->vhtopmode != NULL) {
772 		IEEE80211_VERIFY_LENGTH(scan->vhtopmode[1],
773 		    sizeof(struct ieee80211_ie_vht_operation) - 2,
774 		    scan->vhtopmode = NULL);
775 	}
776 
777 	return scan->status;
778 }
779 
780 /*
781  * Parse an Action frame.  Return 0 on success, non-zero on failure.
782  */
783 int
784 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
785 {
786 	struct ieee80211vap *vap = ni->ni_vap;
787 	const struct ieee80211_action *ia;
788 	struct ieee80211_frame *wh;
789 	uint8_t *frm, *efrm;
790 
791 	/*
792 	 * action frame format:
793 	 *	[1] category
794 	 *	[1] action
795 	 *	[tlv] parameters
796 	 */
797 	wh = mtod(m, struct ieee80211_frame *);
798 	frm = (u_int8_t *)&wh[1];
799 	efrm = mtod(m, u_int8_t *) + m->m_len;
800 	IEEE80211_VERIFY_LENGTH(efrm - frm,
801 		sizeof(struct ieee80211_action), return EINVAL);
802 	ia = (const struct ieee80211_action *) frm;
803 
804 	vap->iv_stats.is_rx_action++;
805 	IEEE80211_NODE_STAT(ni, rx_action);
806 
807 	/* verify frame payloads but defer processing */
808 	switch (ia->ia_category) {
809 	case IEEE80211_ACTION_CAT_BA:
810 		switch (ia->ia_action) {
811 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
812 			IEEE80211_VERIFY_LENGTH(efrm - frm,
813 			    sizeof(struct ieee80211_action_ba_addbarequest),
814 			    return EINVAL);
815 			break;
816 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
817 			IEEE80211_VERIFY_LENGTH(efrm - frm,
818 			    sizeof(struct ieee80211_action_ba_addbaresponse),
819 			    return EINVAL);
820 			break;
821 		case IEEE80211_ACTION_BA_DELBA:
822 			IEEE80211_VERIFY_LENGTH(efrm - frm,
823 			    sizeof(struct ieee80211_action_ba_delba),
824 			    return EINVAL);
825 			break;
826 		}
827 		break;
828 	case IEEE80211_ACTION_CAT_HT:
829 		switch (ia->ia_action) {
830 		case IEEE80211_ACTION_HT_TXCHWIDTH:
831 			IEEE80211_VERIFY_LENGTH(efrm - frm,
832 			    sizeof(struct ieee80211_action_ht_txchwidth),
833 			    return EINVAL);
834 			break;
835 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
836 			IEEE80211_VERIFY_LENGTH(efrm - frm,
837 			    sizeof(struct ieee80211_action_ht_mimopowersave),
838 			    return EINVAL);
839 			break;
840 		}
841 		break;
842 #ifdef IEEE80211_SUPPORT_MESH
843 	case IEEE80211_ACTION_CAT_MESH:
844 		switch (ia->ia_action) {
845 		case IEEE80211_ACTION_MESH_LMETRIC:
846 			/*
847 			 * XXX: verification is true only if we are using
848 			 * Airtime link metric (default)
849 			 */
850 			IEEE80211_VERIFY_LENGTH(efrm - frm,
851 			    sizeof(struct ieee80211_meshlmetric_ie),
852 			    return EINVAL);
853 			break;
854 		case IEEE80211_ACTION_MESH_HWMP:
855 			/* verify something */
856 			break;
857 		case IEEE80211_ACTION_MESH_GANN:
858 			IEEE80211_VERIFY_LENGTH(efrm - frm,
859 			    sizeof(struct ieee80211_meshgann_ie),
860 			    return EINVAL);
861 			break;
862 		case IEEE80211_ACTION_MESH_CC:
863 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
864 		case IEEE80211_ACTION_MESH_MCCA_SREP:
865 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
866 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
867 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
868 		case IEEE80211_ACTION_MESH_TBTT_REQ:
869 		case IEEE80211_ACTION_MESH_TBTT_RES:
870 			/* reject these early on, not implemented */
871 			IEEE80211_DISCARD(vap,
872 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
873 			    wh, NULL, "not implemented yet, act=0x%02X",
874 			    ia->ia_action);
875 			return EINVAL;
876 		}
877 		break;
878 	case IEEE80211_ACTION_CAT_SELF_PROT:
879 		/* If TA or RA group address discard silently */
880 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
881 			IEEE80211_IS_MULTICAST(wh->i_addr2))
882 			return EINVAL;
883 		/*
884 		 * XXX: Should we verify complete length now or it is
885 		 * to varying in sizes?
886 		 */
887 		switch (ia->ia_action) {
888 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
889 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
890 			/* is not a peering candidate (yet) */
891 			if (ni == vap->iv_bss)
892 				return EINVAL;
893 			break;
894 		}
895 		break;
896 #endif
897 	case IEEE80211_ACTION_CAT_VHT:
898 		printf("%s: TODO: VHT handling!\n", __func__);
899 		break;
900 	}
901 	return 0;
902 }
903 
904 #ifdef IEEE80211_DEBUG
905 /*
906  * Debugging support.
907  */
908 void
909 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
910 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
911 {
912 	printf("[%s] discard %s frame, ssid mismatch: ",
913 		ether_sprintf(mac), tag);
914 	ieee80211_print_essid(ssid + 2, ssid[1]);
915 	printf("\n");
916 }
917 
918 /*
919  * Return the bssid of a frame.
920  */
921 static const uint8_t *
922 ieee80211_getbssid(const struct ieee80211vap *vap,
923 	const struct ieee80211_frame *wh)
924 {
925 	if (vap->iv_opmode == IEEE80211_M_STA)
926 		return wh->i_addr2;
927 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
928 		return wh->i_addr1;
929 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
930 		return wh->i_addr1;
931 	return wh->i_addr3;
932 }
933 
934 #include <machine/stdarg.h>
935 
936 void
937 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
938 {
939 	char buf[256];		/* XXX */
940 	va_list ap;
941 	int len;
942 
943 	va_start(ap, fmt);
944 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
945 	va_end(ap);
946 
947 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
948 
949 	if (len >= sizeof(buf))
950 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
951 }
952 
953 void
954 ieee80211_note_frame(const struct ieee80211vap *vap,
955 	const struct ieee80211_frame *wh,
956 	const char *fmt, ...)
957 {
958 	char buf[256];		/* XXX */
959 	va_list ap;
960 	int len;
961 
962 	va_start(ap, fmt);
963 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
964 	va_end(ap);
965 	if_printf(vap->iv_ifp, "[%s] %s\n",
966 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
967 
968 	if (len >= sizeof(buf))
969 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
970 }
971 
972 void
973 ieee80211_note_mac(const struct ieee80211vap *vap,
974 	const uint8_t mac[IEEE80211_ADDR_LEN],
975 	const char *fmt, ...)
976 {
977 	char buf[256];		/* XXX */
978 	va_list ap;
979 	int len;
980 
981 	va_start(ap, fmt);
982 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
983 	va_end(ap);
984 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
985 
986 	if (len >= sizeof(buf))
987 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
988 }
989 
990 void
991 ieee80211_discard_frame(const struct ieee80211vap *vap,
992 	const struct ieee80211_frame *wh,
993 	const char *type, const char *fmt, ...)
994 {
995 	char buf[256];		/* XXX */
996 	va_list ap;
997 	int len;
998 
999 	va_start(ap, fmt);
1000 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1001 	va_end(ap);
1002 
1003 	if_printf(vap->iv_ifp, "[%s] discard %s frame, %s\n",
1004 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1005 	    type != NULL ? type : ieee80211_mgt_subtype_name(wh->i_fc[0]),
1006 	    buf);
1007 
1008 	if (len >= sizeof(buf))
1009 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1010 }
1011 
1012 void
1013 ieee80211_discard_ie(const struct ieee80211vap *vap,
1014 	const struct ieee80211_frame *wh,
1015 	const char *type, const char *fmt, ...)
1016 {
1017 	char buf[256];		/* XXX */
1018 	va_list ap;
1019 	int len;
1020 
1021 	va_start(ap, fmt);
1022 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1023 	va_end(ap);
1024 
1025 	if_printf(vap->iv_ifp, "[%s] discard%s%s information element, %s\n",
1026 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1027 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1028 
1029 	if (len >= sizeof(buf))
1030 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1031 }
1032 
1033 void
1034 ieee80211_discard_mac(const struct ieee80211vap *vap,
1035 	const uint8_t mac[IEEE80211_ADDR_LEN],
1036 	const char *type, const char *fmt, ...)
1037 {
1038 	char buf[256];		/* XXX */
1039 	va_list ap;
1040 	int len;
1041 
1042 	va_start(ap, fmt);
1043 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1044 	va_end(ap);
1045 
1046 	if_printf(vap->iv_ifp, "[%s] discard%s%s frame, %s\n",
1047 	    ether_sprintf(mac),
1048 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1049 
1050 	if (len >= sizeof(buf))
1051 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1052 }
1053 #endif /* IEEE80211_DEBUG */
1054