xref: /freebsd/sys/net80211/ieee80211_input.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
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 epoch_tracker et;
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 	NET_EPOCH_ENTER(et);
309 	ifp->if_input(ifp, m);
310 	NET_EPOCH_EXIT(et);
311 }
312 
313 struct mbuf *
314 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen,
315 	uint8_t qos)
316 {
317 	struct ieee80211_qosframe_addr4 wh;
318 	struct ether_header *eh;
319 	struct llc *llc;
320 
321 	KASSERT(hdrlen <= sizeof(wh),
322 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
323 
324 	if (m->m_len < hdrlen + sizeof(*llc) &&
325 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
326 		vap->iv_stats.is_rx_tooshort++;
327 		/* XXX msg */
328 		return NULL;
329 	}
330 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
331 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
332 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
333 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
334 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
335 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
336 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
337 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX)) &&
338 	    /* Do not want to touch A-MSDU frames. */
339 	    !(qos & IEEE80211_QOS_AMSDU)) {
340 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
341 		llc = NULL;
342 	} else {
343 		m_adj(m, hdrlen - sizeof(*eh));
344 	}
345 	eh = mtod(m, struct ether_header *);
346 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
347 	case IEEE80211_FC1_DIR_NODS:
348 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
349 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
350 		break;
351 	case IEEE80211_FC1_DIR_TODS:
352 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
353 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
354 		break;
355 	case IEEE80211_FC1_DIR_FROMDS:
356 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
357 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
358 		break;
359 	case IEEE80211_FC1_DIR_DSTODS:
360 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
361 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
362 		break;
363 	}
364 #ifndef __NO_STRICT_ALIGNMENT
365 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
366 		m = ieee80211_realign(vap, m, sizeof(*eh));
367 		if (m == NULL)
368 			return NULL;
369 	}
370 #endif /* !__NO_STRICT_ALIGNMENT */
371 	if (llc != NULL) {
372 		eh = mtod(m, struct ether_header *);
373 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
374 	}
375 	return m;
376 }
377 
378 /*
379  * Decap a frame encapsulated in a fast-frame/A-MSDU.
380  */
381 struct mbuf *
382 ieee80211_decap1(struct mbuf *m, int *framelen)
383 {
384 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
385 	struct ether_header *eh;
386 	struct llc *llc;
387 	const uint8_t llc_hdr_mac[ETHER_ADDR_LEN] = {
388 		/* MAC address matching the 802.2 LLC header */
389 		LLC_SNAP_LSAP, LLC_SNAP_LSAP, LLC_UI, 0, 0, 0
390 	};
391 
392 	/*
393 	 * The frame has an 802.3 header followed by an 802.2
394 	 * LLC header.  The encapsulated frame length is in the
395 	 * first header type field; save that and overwrite it
396 	 * with the true type field found in the second.  Then
397 	 * copy the 802.3 header up to where it belongs and
398 	 * adjust the mbuf contents to remove the void.
399 	 */
400 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
401 		return NULL;
402 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
403 
404 	/*
405 	 * Detect possible attack where a single 802.11 frame is processed
406 	 * as an A-MSDU frame due to an adversary setting the A-MSDU present
407 	 * bit in the 802.11 QoS header. [FragAttacks]
408 	 */
409 	if (memcmp(eh->ether_dhost, llc_hdr_mac, ETHER_ADDR_LEN) == 0)
410 		return NULL;
411 
412 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
413 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
414 		  + sizeof(struct ether_header) - sizeof(struct llc);
415 	eh->ether_type = llc->llc_un.type_snap.ether_type;
416 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
417 		sizeof(struct ether_header));
418 	m_adj(m, sizeof(struct llc));
419 	return m;
420 #undef FF_LLC_SIZE
421 }
422 
423 /*
424  * Install received rate set information in the node's state block.
425  */
426 int
427 ieee80211_setup_rates(struct ieee80211_node *ni,
428 	const uint8_t *rates, const uint8_t *xrates, int flags)
429 {
430 	struct ieee80211vap *vap = ni->ni_vap;
431 	struct ieee80211_rateset *rs = &ni->ni_rates;
432 
433 	memset(rs, 0, sizeof(*rs));
434 	rs->rs_nrates = rates[1];
435 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
436 	if (xrates != NULL) {
437 		uint8_t nxrates;
438 		/*
439 		 * Tack on 11g extended supported rate element.
440 		 */
441 		nxrates = xrates[1];
442 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
443 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
444 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
445 			    "extended rate set too large; only using "
446 			    "%u of %u rates", nxrates, xrates[1]);
447 			vap->iv_stats.is_rx_rstoobig++;
448 		}
449 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
450 		rs->rs_nrates += nxrates;
451 	}
452 	return ieee80211_fix_rate(ni, rs, flags);
453 }
454 
455 /*
456  * Send a management frame error response to the specified
457  * station.  If ni is associated with the station then use
458  * it; otherwise allocate a temporary node suitable for
459  * transmitting the frame and then free the reference so
460  * it will go away as soon as the frame has been transmitted.
461  */
462 void
463 ieee80211_send_error(struct ieee80211_node *ni,
464 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
465 {
466 	struct ieee80211vap *vap = ni->ni_vap;
467 	int istmp;
468 
469 	if (ni == vap->iv_bss) {
470 		if (vap->iv_state != IEEE80211_S_RUN) {
471 			/*
472 			 * XXX hack until we get rid of this routine.
473 			 * We can be called prior to the vap reaching
474 			 * run state under certain conditions in which
475 			 * case iv_bss->ni_chan will not be setup.
476 			 * Check for this explicitly and and just ignore
477 			 * the request.
478 			 */
479 			return;
480 		}
481 		ni = ieee80211_tmp_node(vap, mac);
482 		if (ni == NULL) {
483 			/* XXX msg */
484 			return;
485 		}
486 		istmp = 1;
487 	} else
488 		istmp = 0;
489 	IEEE80211_SEND_MGMT(ni, subtype, arg);
490 	if (istmp)
491 		ieee80211_free_node(ni);
492 }
493 
494 int
495 ieee80211_alloc_challenge(struct ieee80211_node *ni)
496 {
497 	if (ni->ni_challenge == NULL)
498 		ni->ni_challenge = (uint32_t *)
499 		    IEEE80211_MALLOC(IEEE80211_CHALLENGE_LEN,
500 		      M_80211_NODE, IEEE80211_M_NOWAIT);
501 	if (ni->ni_challenge == NULL) {
502 		IEEE80211_NOTE(ni->ni_vap,
503 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
504 		    "%s", "shared key challenge alloc failed");
505 		/* XXX statistic */
506 	}
507 	return (ni->ni_challenge != NULL);
508 }
509 
510 /*
511  * Parse a Beacon or ProbeResponse frame and return the
512  * useful information in an ieee80211_scanparams structure.
513  * Status is set to 0 if no problems were found; otherwise
514  * a bitmask of IEEE80211_BPARSE_* items is returned that
515  * describes the problems detected.
516  */
517 int
518 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
519 	struct ieee80211_channel *rxchan, struct ieee80211_scanparams *scan)
520 {
521 	struct ieee80211vap *vap = ni->ni_vap;
522 	struct ieee80211com *ic = ni->ni_ic;
523 	struct ieee80211_frame *wh;
524 	uint8_t *frm, *efrm;
525 
526 	wh = mtod(m, struct ieee80211_frame *);
527 	frm = (uint8_t *)&wh[1];
528 	efrm = mtod(m, uint8_t *) + m->m_len;
529 	scan->status = 0;
530 	/*
531 	 * beacon/probe response frame format
532 	 *
533 	 * XXX Update from 802.11-2012 - eg where HT is
534 	 *	[8] time stamp
535 	 *	[2] beacon interval
536 	 *	[2] capability information
537 	 *	[tlv] ssid
538 	 *	[tlv] supported rates
539 	 *	[tlv] country information
540 	 *	[tlv] channel switch announcement (CSA)
541 	 *	[tlv] parameter set (FH/DS)
542 	 *	[tlv] erp information
543 	 *	[tlv] extended supported rates
544 	 *	[tlv] WME
545 	 *	[tlv] WPA or RSN
546 	 *	[tlv] HT capabilities
547 	 *	[tlv] HT information
548 	 *	[tlv] VHT capabilities
549 	 *	[tlv] VHT information
550 	 *	[tlv] Atheros capabilities
551 	 *	[tlv] Mesh ID
552 	 *	[tlv] Mesh Configuration
553 	 */
554 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
555 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
556 	memset(scan, 0, sizeof(*scan));
557 	scan->tstamp  = frm;				frm += 8;
558 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
559 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
560 	scan->bchan = ieee80211_chan2ieee(ic, rxchan);
561 	scan->chan = scan->bchan;
562 	scan->ies = frm;
563 	scan->ies_len = efrm - frm;
564 
565 	while (efrm - frm > 1) {
566 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
567 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
568 		switch (*frm) {
569 		case IEEE80211_ELEMID_SSID:
570 			scan->ssid = frm;
571 			break;
572 		case IEEE80211_ELEMID_RATES:
573 			scan->rates = frm;
574 			break;
575 		case IEEE80211_ELEMID_COUNTRY:
576 			scan->country = frm;
577 			break;
578 		case IEEE80211_ELEMID_CSA:
579 			scan->csa = frm;
580 			break;
581 		case IEEE80211_ELEMID_QUIET:
582 			scan->quiet = frm;
583 			break;
584 		case IEEE80211_ELEMID_FHPARMS:
585 			if (ic->ic_phytype == IEEE80211_T_FH) {
586 				scan->fhdwell = le16dec(&frm[2]);
587 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
588 				scan->fhindex = frm[6];
589 			}
590 			break;
591 		case IEEE80211_ELEMID_DSPARMS:
592 			/*
593 			 * XXX hack this since depending on phytype
594 			 * is problematic for multi-mode devices.
595 			 */
596 			if (ic->ic_phytype != IEEE80211_T_FH)
597 				scan->chan = frm[2];
598 			break;
599 		case IEEE80211_ELEMID_TIM:
600 			/* XXX ATIM? */
601 			scan->tim = frm;
602 			scan->timoff = frm - mtod(m, uint8_t *);
603 			break;
604 		case IEEE80211_ELEMID_IBSSPARMS:
605 		case IEEE80211_ELEMID_CFPARMS:
606 		case IEEE80211_ELEMID_PWRCNSTR:
607 		case IEEE80211_ELEMID_BSSLOAD:
608 		case IEEE80211_ELEMID_APCHANREP:
609 			/* NB: avoid debugging complaints */
610 			break;
611 		case IEEE80211_ELEMID_XRATES:
612 			scan->xrates = frm;
613 			break;
614 		case IEEE80211_ELEMID_ERP:
615 			if (frm[1] != 1) {
616 				IEEE80211_DISCARD_IE(vap,
617 				    IEEE80211_MSG_ELEMID, wh, "ERP",
618 				    "bad len %u", frm[1]);
619 				vap->iv_stats.is_rx_elem_toobig++;
620 				break;
621 			}
622 			scan->erp = frm[2] | 0x100;
623 			break;
624 		case IEEE80211_ELEMID_HTCAP:
625 			scan->htcap = frm;
626 			break;
627 		case IEEE80211_ELEMID_VHT_CAP:
628 			scan->vhtcap = frm;
629 			break;
630 		case IEEE80211_ELEMID_VHT_OPMODE:
631 			scan->vhtopmode = frm;
632 			break;
633 		case IEEE80211_ELEMID_RSN:
634 			scan->rsn = frm;
635 			break;
636 		case IEEE80211_ELEMID_HTINFO:
637 			scan->htinfo = frm;
638 			break;
639 #ifdef IEEE80211_SUPPORT_MESH
640 		case IEEE80211_ELEMID_MESHID:
641 			scan->meshid = frm;
642 			break;
643 		case IEEE80211_ELEMID_MESHCONF:
644 			scan->meshconf = frm;
645 			break;
646 #endif
647 		/* Extended capabilities; nothing handles it for now */
648 		case IEEE80211_ELEMID_EXTCAP:
649 			break;
650 		case IEEE80211_ELEMID_VENDOR:
651 			if (iswpaoui(frm))
652 				scan->wpa = frm;
653 			else if (iswmeparam(frm) || iswmeinfo(frm))
654 				scan->wme = frm;
655 #ifdef IEEE80211_SUPPORT_SUPERG
656 			else if (isatherosoui(frm))
657 				scan->ath = frm;
658 #endif
659 #ifdef IEEE80211_SUPPORT_TDMA
660 			else if (istdmaoui(frm))
661 				scan->tdma = frm;
662 #endif
663 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
664 				/*
665 				 * Accept pre-draft HT ie's if the
666 				 * standard ones have not been seen.
667 				 */
668 				if (ishtcapoui(frm)) {
669 					if (scan->htcap == NULL)
670 						scan->htcap = frm;
671 				} else if (ishtinfooui(frm)) {
672 					if (scan->htinfo == NULL)
673 						scan->htcap = frm;
674 				}
675 			}
676 			break;
677 		default:
678 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
679 			    wh, "unhandled",
680 			    "id %u, len %u", *frm, frm[1]);
681 			vap->iv_stats.is_rx_elem_unknown++;
682 			break;
683 		}
684 		frm += frm[1] + 2;
685 	}
686 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
687 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
688 	if (scan->rates != NULL && scan->xrates != NULL) {
689 		/*
690 		 * NB: don't process XRATES if RATES is missing.  This
691 		 * avoids a potential null ptr deref and should be ok
692 		 * as the return code will already note RATES is missing
693 		 * (so callers shouldn't otherwise process the frame).
694 		 */
695 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
696 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
697 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
698 	}
699 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
700 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
701 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
702 		/*
703 		 * Frame was received on a channel different from the
704 		 * one indicated in the DS params element id;
705 		 * silently discard it.
706 		 *
707 		 * NB: this can happen due to signal leakage.
708 		 *     But we should take it for FH phy because
709 		 *     the rssi value should be correct even for
710 		 *     different hop pattern in FH.
711 		 */
712 		IEEE80211_DISCARD(vap,
713 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
714 		    wh, NULL, "for off-channel %u (bchan=%u)",
715 		    scan->chan, scan->bchan);
716 		vap->iv_stats.is_rx_chanmismatch++;
717 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
718 	}
719 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
720 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
721 		IEEE80211_DISCARD(vap,
722 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
723 		    wh, NULL, "bogus beacon interval (%d TU)",
724 		    (int) scan->bintval);
725 		vap->iv_stats.is_rx_badbintval++;
726 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
727 	}
728 	if (scan->country != NULL) {
729 		/*
730 		 * Validate we have at least enough data to extract
731 		 * the country code.  Not sure if we should return an
732 		 * error instead of discarding the IE; consider this
733 		 * being lenient as we don't depend on the data for
734 		 * correct operation.
735 		 */
736 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
737 		    scan->country = NULL);
738 	}
739 	if (scan->csa != NULL) {
740 		/*
741 		 * Validate Channel Switch Announcement; this must
742 		 * be the correct length or we toss the frame.
743 		 */
744 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
745 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
746 	}
747 #ifdef IEEE80211_SUPPORT_MESH
748 	if (scan->meshid != NULL) {
749 		IEEE80211_VERIFY_ELEMENT(scan->meshid, IEEE80211_MESHID_LEN,
750 		    scan->status |= IEEE80211_BPARSE_MESHID_INVALID);
751 	}
752 #endif
753 	/*
754 	 * Process HT ie's.  This is complicated by our
755 	 * accepting both the standard ie's and the pre-draft
756 	 * vendor OUI ie's that some vendors still use/require.
757 	 */
758 	if (scan->htcap != NULL) {
759 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
760 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
761 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
762 			 sizeof(struct ieee80211_ie_htcap)-2,
763 		     scan->htcap = NULL);
764 	}
765 	if (scan->htinfo != NULL) {
766 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
767 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
768 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
769 			 sizeof(struct ieee80211_ie_htinfo)-2,
770 		     scan->htinfo = NULL);
771 	}
772 
773 	/* Process VHT IEs */
774 	if (scan->vhtcap != NULL) {
775 		IEEE80211_VERIFY_LENGTH(scan->vhtcap[1],
776 		    sizeof(struct ieee80211_vht_cap),
777 		    scan->vhtcap = NULL);
778 	}
779 	if (scan->vhtopmode != NULL) {
780 		IEEE80211_VERIFY_LENGTH(scan->vhtopmode[1],
781 		    sizeof(struct ieee80211_vht_operation),
782 		    scan->vhtopmode = NULL);
783 	}
784 
785 	return scan->status;
786 }
787 
788 /*
789  * Parse an Action frame.  Return 0 on success, non-zero on failure.
790  */
791 int
792 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
793 {
794 	struct ieee80211vap *vap = ni->ni_vap;
795 	const struct ieee80211_action *ia;
796 	struct ieee80211_frame *wh;
797 	uint8_t *frm, *efrm;
798 
799 	/*
800 	 * action frame format:
801 	 *	[1] category
802 	 *	[1] action
803 	 *	[tlv] parameters
804 	 */
805 	wh = mtod(m, struct ieee80211_frame *);
806 	frm = (u_int8_t *)&wh[1];
807 	efrm = mtod(m, u_int8_t *) + m->m_len;
808 	IEEE80211_VERIFY_LENGTH(efrm - frm,
809 		sizeof(struct ieee80211_action), return EINVAL);
810 	ia = (const struct ieee80211_action *) frm;
811 
812 	vap->iv_stats.is_rx_action++;
813 	IEEE80211_NODE_STAT(ni, rx_action);
814 
815 	/* verify frame payloads but defer processing */
816 	switch (ia->ia_category) {
817 	case IEEE80211_ACTION_CAT_BA:
818 		switch (ia->ia_action) {
819 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
820 			IEEE80211_VERIFY_LENGTH(efrm - frm,
821 			    sizeof(struct ieee80211_action_ba_addbarequest),
822 			    return EINVAL);
823 			break;
824 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
825 			IEEE80211_VERIFY_LENGTH(efrm - frm,
826 			    sizeof(struct ieee80211_action_ba_addbaresponse),
827 			    return EINVAL);
828 			break;
829 		case IEEE80211_ACTION_BA_DELBA:
830 			IEEE80211_VERIFY_LENGTH(efrm - frm,
831 			    sizeof(struct ieee80211_action_ba_delba),
832 			    return EINVAL);
833 			break;
834 		}
835 		break;
836 	case IEEE80211_ACTION_CAT_HT:
837 		switch (ia->ia_action) {
838 		case IEEE80211_ACTION_HT_TXCHWIDTH:
839 			IEEE80211_VERIFY_LENGTH(efrm - frm,
840 			    sizeof(struct ieee80211_action_ht_txchwidth),
841 			    return EINVAL);
842 			break;
843 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
844 			IEEE80211_VERIFY_LENGTH(efrm - frm,
845 			    sizeof(struct ieee80211_action_ht_mimopowersave),
846 			    return EINVAL);
847 			break;
848 		}
849 		break;
850 #ifdef IEEE80211_SUPPORT_MESH
851 	case IEEE80211_ACTION_CAT_MESH:
852 		switch (ia->ia_action) {
853 		case IEEE80211_ACTION_MESH_LMETRIC:
854 			/*
855 			 * XXX: verification is true only if we are using
856 			 * Airtime link metric (default)
857 			 */
858 			IEEE80211_VERIFY_LENGTH(efrm - frm,
859 			    sizeof(struct ieee80211_meshlmetric_ie),
860 			    return EINVAL);
861 			break;
862 		case IEEE80211_ACTION_MESH_HWMP:
863 			/* verify something */
864 			break;
865 		case IEEE80211_ACTION_MESH_GANN:
866 			IEEE80211_VERIFY_LENGTH(efrm - frm,
867 			    sizeof(struct ieee80211_meshgann_ie),
868 			    return EINVAL);
869 			break;
870 		case IEEE80211_ACTION_MESH_CC:
871 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
872 		case IEEE80211_ACTION_MESH_MCCA_SREP:
873 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
874 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
875 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
876 		case IEEE80211_ACTION_MESH_TBTT_REQ:
877 		case IEEE80211_ACTION_MESH_TBTT_RES:
878 			/* reject these early on, not implemented */
879 			IEEE80211_DISCARD(vap,
880 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
881 			    wh, NULL, "not implemented yet, act=0x%02X",
882 			    ia->ia_action);
883 			return EINVAL;
884 		}
885 		break;
886 	case IEEE80211_ACTION_CAT_SELF_PROT:
887 		/* If TA or RA group address discard silently */
888 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
889 			IEEE80211_IS_MULTICAST(wh->i_addr2))
890 			return EINVAL;
891 		/*
892 		 * XXX: Should we verify complete length now or it is
893 		 * to varying in sizes?
894 		 */
895 		switch (ia->ia_action) {
896 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
897 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
898 			/* is not a peering candidate (yet) */
899 			if (ni == vap->iv_bss)
900 				return EINVAL;
901 			break;
902 		}
903 		break;
904 #endif
905 	case IEEE80211_ACTION_CAT_VHT:
906 		printf("%s: TODO: VHT handling!\n", __func__);
907 		break;
908 	}
909 	return 0;
910 }
911 
912 #ifdef IEEE80211_DEBUG
913 /*
914  * Debugging support.
915  */
916 void
917 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
918 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
919 {
920 	printf("[%s] discard %s frame, ssid mismatch: ",
921 		ether_sprintf(mac), tag);
922 	ieee80211_print_essid(ssid + 2, ssid[1]);
923 	printf("\n");
924 }
925 
926 /*
927  * Return the bssid of a frame.
928  */
929 static const uint8_t *
930 ieee80211_getbssid(const struct ieee80211vap *vap,
931 	const struct ieee80211_frame *wh)
932 {
933 	if (vap->iv_opmode == IEEE80211_M_STA)
934 		return wh->i_addr2;
935 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
936 		return wh->i_addr1;
937 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
938 		return wh->i_addr1;
939 	return wh->i_addr3;
940 }
941 
942 #include <machine/stdarg.h>
943 
944 void
945 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
946 {
947 	char buf[256];		/* XXX */
948 	va_list ap;
949 	int len;
950 
951 	va_start(ap, fmt);
952 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
953 	va_end(ap);
954 
955 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
956 
957 	if (len >= sizeof(buf))
958 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
959 }
960 
961 void
962 ieee80211_note_frame(const struct ieee80211vap *vap,
963 	const struct ieee80211_frame *wh,
964 	const char *fmt, ...)
965 {
966 	char buf[256];		/* XXX */
967 	va_list ap;
968 	int len;
969 
970 	va_start(ap, fmt);
971 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
972 	va_end(ap);
973 	if_printf(vap->iv_ifp, "[%s] %s\n",
974 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
975 
976 	if (len >= sizeof(buf))
977 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
978 }
979 
980 void
981 ieee80211_note_mac(const struct ieee80211vap *vap,
982 	const uint8_t mac[IEEE80211_ADDR_LEN],
983 	const char *fmt, ...)
984 {
985 	char buf[256];		/* XXX */
986 	va_list ap;
987 	int len;
988 
989 	va_start(ap, fmt);
990 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
991 	va_end(ap);
992 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
993 
994 	if (len >= sizeof(buf))
995 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
996 }
997 
998 void
999 ieee80211_discard_frame(const struct ieee80211vap *vap,
1000 	const struct ieee80211_frame *wh,
1001 	const char *type, const char *fmt, ...)
1002 {
1003 	char buf[256];		/* XXX */
1004 	va_list ap;
1005 	int len;
1006 
1007 	va_start(ap, fmt);
1008 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1009 	va_end(ap);
1010 
1011 	if_printf(vap->iv_ifp, "[%s] discard %s frame, %s\n",
1012 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1013 	    type != NULL ? type : ieee80211_mgt_subtype_name(wh->i_fc[0]),
1014 	    buf);
1015 
1016 	if (len >= sizeof(buf))
1017 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1018 }
1019 
1020 void
1021 ieee80211_discard_ie(const struct ieee80211vap *vap,
1022 	const struct ieee80211_frame *wh,
1023 	const char *type, const char *fmt, ...)
1024 {
1025 	char buf[256];		/* XXX */
1026 	va_list ap;
1027 	int len;
1028 
1029 	va_start(ap, fmt);
1030 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1031 	va_end(ap);
1032 
1033 	if_printf(vap->iv_ifp, "[%s] discard%s%s information element, %s\n",
1034 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1035 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1036 
1037 	if (len >= sizeof(buf))
1038 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1039 }
1040 
1041 void
1042 ieee80211_discard_mac(const struct ieee80211vap *vap,
1043 	const uint8_t mac[IEEE80211_ADDR_LEN],
1044 	const char *type, const char *fmt, ...)
1045 {
1046 	char buf[256];		/* XXX */
1047 	va_list ap;
1048 	int len;
1049 
1050 	va_start(ap, fmt);
1051 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1052 	va_end(ap);
1053 
1054 	if_printf(vap->iv_ifp, "[%s] discard%s%s frame, %s\n",
1055 	    ether_sprintf(mac),
1056 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1057 
1058 	if (len >= sizeof(buf))
1059 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1060 }
1061 #endif /* IEEE80211_DEBUG */
1062