xref: /freebsd/sys/net80211/ieee80211_input.c (revision 4d846d260e2b9a3d4d0a701462568268cbfe7a5b)
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 __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_private.h>
49 #include <net/if_vlan_var.h>
50 
51 #include <net80211/ieee80211_var.h>
52 #include <net80211/ieee80211_input.h>
53 #ifdef IEEE80211_SUPPORT_MESH
54 #include <net80211/ieee80211_mesh.h>
55 #endif
56 
57 #include <net/bpf.h>
58 
59 #ifdef INET
60 #include <netinet/in.h>
61 #include <net/ethernet.h>
62 #endif
63 
64 static void
65 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
66 {
67 	int i;
68 
69 	/* Verify the required MIMO bits are set */
70 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
71 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
72 		return;
73 
74 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
75 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
76 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
77 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
78 	}
79 
80 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
81 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
82 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
83 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
84 	}
85 	ni->ni_mimo_chains = rx->c_chain;
86 }
87 
88 int
89 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m)
90 {
91 	struct ieee80211_rx_stats rxs;
92 
93 	/* try to read stats from mbuf */
94 	bzero(&rxs, sizeof(rxs));
95 	if (ieee80211_get_rx_params(m, &rxs) != 0)
96 		return (-1);
97 
98 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
99 	ieee80211_process_mimo(ni, &rxs);
100 
101 	//return ieee80211_input(ni, m, rx->rssi, rx->nf);
102 	return ni->ni_vap->iv_input(ni, m, &rxs, rxs.c_rssi, rxs.c_nf);
103 }
104 
105 int
106 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
107 {
108 	struct ieee80211_rx_stats rx;
109 
110 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
111 	rx.c_nf = nf;
112 	rx.c_rssi = rssi;
113 
114 	if (!ieee80211_add_rx_params(m, &rx))
115 		return (-1);
116 
117 	return ieee80211_input_mimo_all(ic, m);
118 }
119 
120 int
121 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m)
122 {
123 	struct ieee80211vap *vap;
124 	int type = -1;
125 
126 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
127 
128 	/* XXX locking */
129 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
130 		struct ieee80211_node *ni;
131 		struct mbuf *mcopy;
132 
133 		/* NB: could check for IFF_UP but this is cheaper */
134 		if (vap->iv_state == IEEE80211_S_INIT)
135 			continue;
136 		/*
137 		 * WDS vap's only receive directed traffic from the
138 		 * station at the ``far end''.  That traffic should
139 		 * be passed through the AP vap the station is associated
140 		 * to--so don't spam them with mcast frames.
141 		 */
142 		if (vap->iv_opmode == IEEE80211_M_WDS)
143 			continue;
144 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
145 			/*
146 			 * Packet contents are changed by ieee80211_decap
147 			 * so do a deep copy of the packet.
148 			 * NB: tags are copied too.
149 			 */
150 			mcopy = m_dup(m, IEEE80211_M_NOWAIT);
151 			if (mcopy == NULL) {
152 				/* XXX stat+msg */
153 				continue;
154 			}
155 		} else {
156 			mcopy = m;
157 			m = NULL;
158 		}
159 		ni = ieee80211_ref_node(vap->iv_bss);
160 		type = ieee80211_input_mimo(ni, mcopy);
161 		ieee80211_free_node(ni);
162 	}
163 	if (m != NULL)			/* no vaps, reclaim mbuf */
164 		m_freem(m);
165 	return type;
166 }
167 
168 /*
169  * This function reassembles fragments.
170  *
171  * XXX should handle 3 concurrent reassemblies per-spec.
172  */
173 struct mbuf *
174 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace,
175 	int has_decrypted)
176 {
177 	struct ieee80211vap *vap = ni->ni_vap;
178 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
179 	struct ieee80211_frame *lwh;
180 	uint16_t rxseq;
181 	uint8_t fragno;
182 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
183 	struct mbuf *mfrag;
184 
185 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
186 
187 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
188 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
189 
190 	/* Quick way out, if there's nothing to defragment */
191 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
192 		return m;
193 
194 	/* Temporarily set flag to remember if fragment was encrypted. */
195 	/* XXX use a non-packet altering storage for this in the future. */
196 	if (has_decrypted)
197 		wh->i_fc[1] |= IEEE80211_FC1_PROTECTED;
198 
199 	/*
200 	 * Remove frag to insure it doesn't get reaped by timer.
201 	 */
202 	if (ni->ni_table == NULL) {
203 		/*
204 		 * Should never happen.  If the node is orphaned (not in
205 		 * the table) then input packets should not reach here.
206 		 * Otherwise, a concurrent request that yanks the table
207 		 * should be blocked by other interlocking and/or by first
208 		 * shutting the driver down.  Regardless, be defensive
209 		 * here and just bail
210 		 */
211 		/* XXX need msg+stat */
212 		m_freem(m);
213 		return NULL;
214 	}
215 	IEEE80211_NODE_LOCK(ni->ni_table);
216 	mfrag = ni->ni_rxfrag[0];
217 	ni->ni_rxfrag[0] = NULL;
218 	IEEE80211_NODE_UNLOCK(ni->ni_table);
219 
220 	/*
221 	 * Validate new fragment is in order and
222 	 * related to the previous ones.
223 	 */
224 	if (mfrag != NULL) {
225 		uint16_t last_rxseq;
226 
227 		lwh = mtod(mfrag, struct ieee80211_frame *);
228 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
229 		/*
230 		 * NB: check seq # and frag together. Also check that both
231 		 * fragments are plaintext or that both are encrypted.
232 		 */
233 		if (rxseq == last_rxseq+1 &&
234 		    IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) &&
235 		    IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2) &&
236 		    !((wh->i_fc[1] ^ lwh->i_fc[1]) & IEEE80211_FC1_PROTECTED)) {
237 			/* XXX clear MORE_FRAG bit? */
238 			/* track last seqnum and fragno */
239 			*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
240 
241 			m_adj(m, hdrspace);		/* strip header */
242 			m_catpkt(mfrag, m);		/* concatenate */
243 		} else {
244 			/*
245 			 * Unrelated fragment or no space for it,
246 			 * clear current fragments.
247 			 */
248 			m_freem(mfrag);
249 			mfrag = NULL;
250 		}
251 	}
252 
253  	if (mfrag == NULL) {
254 		if (fragno != 0) {		/* !first fragment, discard */
255 			vap->iv_stats.is_rx_defrag++;
256 			IEEE80211_NODE_STAT(ni, rx_defrag);
257 			m_freem(m);
258 			return NULL;
259 		}
260 		mfrag = m;
261 	}
262 	if (more_frag) {			/* more to come, save */
263 		ni->ni_rxfragstamp = ticks;
264 		ni->ni_rxfrag[0] = mfrag;
265 		mfrag = NULL;
266 	}
267 	/* Remember to clear protected flag that was temporarily set. */
268 	if (mfrag != NULL) {
269 		wh = mtod(mfrag, struct ieee80211_frame *);
270 		wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
271 	}
272 	return mfrag;
273 }
274 
275 void
276 ieee80211_deliver_data(struct ieee80211vap *vap,
277 	struct ieee80211_node *ni, struct mbuf *m)
278 {
279 	struct ether_header *eh = mtod(m, struct ether_header *);
280 	struct ifnet *ifp = vap->iv_ifp;
281 
282 	/* clear driver/net80211 flags before passing up */
283 	m->m_flags &= ~(M_MCAST | M_BCAST);
284 	m_clrprotoflags(m);
285 
286 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
287 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
288 	/*
289 	 * Do accounting.
290 	 */
291 	if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
292 	IEEE80211_NODE_STAT(ni, rx_data);
293 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
294 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
295 		if (ETHER_IS_BROADCAST(eh->ether_dhost))
296 			m->m_flags |= M_BCAST;
297 		else
298 			m->m_flags |= M_MCAST;
299 		IEEE80211_NODE_STAT(ni, rx_mcast);
300 	} else
301 		IEEE80211_NODE_STAT(ni, rx_ucast);
302 	m->m_pkthdr.rcvif = ifp;
303 
304 	if (ni->ni_vlan != 0) {
305 		/* attach vlan tag */
306 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
307 		m->m_flags |= M_VLANTAG;
308 	}
309 	ifp->if_input(ifp, m);
310 }
311 
312 struct mbuf *
313 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen,
314 	uint8_t qos)
315 {
316 	struct ieee80211_qosframe_addr4 wh;
317 	struct ether_header *eh;
318 	struct llc *llc;
319 
320 	KASSERT(hdrlen <= sizeof(wh),
321 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
322 
323 	if (m->m_len < hdrlen + sizeof(*llc) &&
324 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
325 		vap->iv_stats.is_rx_tooshort++;
326 		/* XXX msg */
327 		return NULL;
328 	}
329 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
330 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
331 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
332 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
333 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
334 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
335 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
336 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX)) &&
337 	    /* Do not want to touch A-MSDU frames. */
338 	    !(qos & IEEE80211_QOS_AMSDU)) {
339 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
340 		llc = NULL;
341 	} else {
342 		m_adj(m, hdrlen - sizeof(*eh));
343 	}
344 	eh = mtod(m, struct ether_header *);
345 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
346 	case IEEE80211_FC1_DIR_NODS:
347 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
348 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
349 		break;
350 	case IEEE80211_FC1_DIR_TODS:
351 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
352 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
353 		break;
354 	case IEEE80211_FC1_DIR_FROMDS:
355 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
356 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
357 		break;
358 	case IEEE80211_FC1_DIR_DSTODS:
359 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
360 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
361 		break;
362 	}
363 #ifndef __NO_STRICT_ALIGNMENT
364 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
365 		m = ieee80211_realign(vap, m, sizeof(*eh));
366 		if (m == NULL)
367 			return NULL;
368 	}
369 #endif /* !__NO_STRICT_ALIGNMENT */
370 	if (llc != NULL) {
371 		eh = mtod(m, struct ether_header *);
372 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
373 	}
374 	return m;
375 }
376 
377 /*
378  * Decap a frame encapsulated in a fast-frame/A-MSDU.
379  */
380 struct mbuf *
381 ieee80211_decap1(struct mbuf *m, int *framelen)
382 {
383 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
384 	struct ether_header *eh;
385 	struct llc *llc;
386 	const uint8_t llc_hdr_mac[ETHER_ADDR_LEN] = {
387 		/* MAC address matching the 802.2 LLC header */
388 		LLC_SNAP_LSAP, LLC_SNAP_LSAP, LLC_UI, 0, 0, 0
389 	};
390 
391 	/*
392 	 * The frame has an 802.3 header followed by an 802.2
393 	 * LLC header.  The encapsulated frame length is in the
394 	 * first header type field; save that and overwrite it
395 	 * with the true type field found in the second.  Then
396 	 * copy the 802.3 header up to where it belongs and
397 	 * adjust the mbuf contents to remove the void.
398 	 */
399 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
400 		return NULL;
401 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
402 
403 	/*
404 	 * Detect possible attack where a single 802.11 frame is processed
405 	 * as an A-MSDU frame due to an adversary setting the A-MSDU present
406 	 * bit in the 802.11 QoS header. [FragAttacks]
407 	 */
408 	if (memcmp(eh->ether_dhost, llc_hdr_mac, ETHER_ADDR_LEN) == 0)
409 		return NULL;
410 
411 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
412 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
413 		  + sizeof(struct ether_header) - sizeof(struct llc);
414 	eh->ether_type = llc->llc_un.type_snap.ether_type;
415 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
416 		sizeof(struct ether_header));
417 	m_adj(m, sizeof(struct llc));
418 	return m;
419 #undef FF_LLC_SIZE
420 }
421 
422 /*
423  * Install received rate set information in the node's state block.
424  */
425 int
426 ieee80211_setup_rates(struct ieee80211_node *ni,
427 	const uint8_t *rates, const uint8_t *xrates, int flags)
428 {
429 	struct ieee80211vap *vap = ni->ni_vap;
430 	struct ieee80211_rateset *rs = &ni->ni_rates;
431 
432 	memset(rs, 0, sizeof(*rs));
433 	rs->rs_nrates = rates[1];
434 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
435 	if (xrates != NULL) {
436 		uint8_t nxrates;
437 		/*
438 		 * Tack on 11g extended supported rate element.
439 		 */
440 		nxrates = xrates[1];
441 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
442 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
443 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
444 			    "extended rate set too large; only using "
445 			    "%u of %u rates", nxrates, xrates[1]);
446 			vap->iv_stats.is_rx_rstoobig++;
447 		}
448 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
449 		rs->rs_nrates += nxrates;
450 	}
451 	return ieee80211_fix_rate(ni, rs, flags);
452 }
453 
454 /*
455  * Send a management frame error response to the specified
456  * station.  If ni is associated with the station then use
457  * it; otherwise allocate a temporary node suitable for
458  * transmitting the frame and then free the reference so
459  * it will go away as soon as the frame has been transmitted.
460  */
461 void
462 ieee80211_send_error(struct ieee80211_node *ni,
463 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
464 {
465 	struct ieee80211vap *vap = ni->ni_vap;
466 	int istmp;
467 
468 	if (ni == vap->iv_bss) {
469 		if (vap->iv_state != IEEE80211_S_RUN) {
470 			/*
471 			 * XXX hack until we get rid of this routine.
472 			 * We can be called prior to the vap reaching
473 			 * run state under certain conditions in which
474 			 * case iv_bss->ni_chan will not be setup.
475 			 * Check for this explicitly and and just ignore
476 			 * the request.
477 			 */
478 			return;
479 		}
480 		ni = ieee80211_tmp_node(vap, mac);
481 		if (ni == NULL) {
482 			/* XXX msg */
483 			return;
484 		}
485 		istmp = 1;
486 	} else
487 		istmp = 0;
488 	IEEE80211_SEND_MGMT(ni, subtype, arg);
489 	if (istmp)
490 		ieee80211_free_node(ni);
491 }
492 
493 int
494 ieee80211_alloc_challenge(struct ieee80211_node *ni)
495 {
496 	if (ni->ni_challenge == NULL)
497 		ni->ni_challenge = (uint32_t *)
498 		    IEEE80211_MALLOC(IEEE80211_CHALLENGE_LEN,
499 		      M_80211_NODE, IEEE80211_M_NOWAIT);
500 	if (ni->ni_challenge == NULL) {
501 		IEEE80211_NOTE(ni->ni_vap,
502 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
503 		    "%s", "shared key challenge alloc failed");
504 		/* XXX statistic */
505 	}
506 	return (ni->ni_challenge != NULL);
507 }
508 
509 /*
510  * Parse a Beacon or ProbeResponse frame and return the
511  * useful information in an ieee80211_scanparams structure.
512  * Status is set to 0 if no problems were found; otherwise
513  * a bitmask of IEEE80211_BPARSE_* items is returned that
514  * describes the problems detected.
515  */
516 int
517 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
518 	struct ieee80211_channel *rxchan, struct ieee80211_scanparams *scan)
519 {
520 	struct ieee80211vap *vap = ni->ni_vap;
521 	struct ieee80211com *ic = ni->ni_ic;
522 	struct ieee80211_frame *wh;
523 	uint8_t *frm, *efrm;
524 
525 	wh = mtod(m, struct ieee80211_frame *);
526 	frm = (uint8_t *)&wh[1];
527 	efrm = mtod(m, uint8_t *) + m->m_len;
528 	scan->status = 0;
529 	/*
530 	 * beacon/probe response frame format
531 	 *
532 	 * XXX Update from 802.11-2012 - eg where HT is
533 	 *	[8] time stamp
534 	 *	[2] beacon interval
535 	 *	[2] capability information
536 	 *	[tlv] ssid
537 	 *	[tlv] supported rates
538 	 *	[tlv] country information
539 	 *	[tlv] channel switch announcement (CSA)
540 	 *	[tlv] parameter set (FH/DS)
541 	 *	[tlv] erp information
542 	 *	[tlv] extended supported rates
543 	 *	[tlv] WME
544 	 *	[tlv] WPA or RSN
545 	 *	[tlv] HT capabilities
546 	 *	[tlv] HT information
547 	 *	[tlv] VHT capabilities
548 	 *	[tlv] VHT information
549 	 *	[tlv] Atheros capabilities
550 	 *	[tlv] Mesh ID
551 	 *	[tlv] Mesh Configuration
552 	 */
553 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
554 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
555 	memset(scan, 0, sizeof(*scan));
556 	scan->tstamp  = frm;				frm += 8;
557 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
558 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
559 	scan->bchan = ieee80211_chan2ieee(ic, rxchan);
560 	scan->chan = scan->bchan;
561 	scan->ies = frm;
562 	scan->ies_len = efrm - frm;
563 
564 	while (efrm - frm > 1) {
565 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
566 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
567 		switch (*frm) {
568 		case IEEE80211_ELEMID_SSID:
569 			scan->ssid = frm;
570 			break;
571 		case IEEE80211_ELEMID_RATES:
572 			scan->rates = frm;
573 			break;
574 		case IEEE80211_ELEMID_COUNTRY:
575 			scan->country = frm;
576 			break;
577 		case IEEE80211_ELEMID_CSA:
578 			scan->csa = frm;
579 			break;
580 		case IEEE80211_ELEMID_QUIET:
581 			scan->quiet = frm;
582 			break;
583 		case IEEE80211_ELEMID_FHPARMS:
584 			if (ic->ic_phytype == IEEE80211_T_FH) {
585 				scan->fhdwell = le16dec(&frm[2]);
586 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
587 				scan->fhindex = frm[6];
588 			}
589 			break;
590 		case IEEE80211_ELEMID_DSPARMS:
591 			/*
592 			 * XXX hack this since depending on phytype
593 			 * is problematic for multi-mode devices.
594 			 */
595 			if (ic->ic_phytype != IEEE80211_T_FH)
596 				scan->chan = frm[2];
597 			break;
598 		case IEEE80211_ELEMID_TIM:
599 			/* XXX ATIM? */
600 			scan->tim = frm;
601 			scan->timoff = frm - mtod(m, uint8_t *);
602 			break;
603 		case IEEE80211_ELEMID_IBSSPARMS:
604 		case IEEE80211_ELEMID_CFPARMS:
605 		case IEEE80211_ELEMID_PWRCNSTR:
606 		case IEEE80211_ELEMID_BSSLOAD:
607 		case IEEE80211_ELEMID_APCHANREP:
608 			/* NB: avoid debugging complaints */
609 			break;
610 		case IEEE80211_ELEMID_XRATES:
611 			scan->xrates = frm;
612 			break;
613 		case IEEE80211_ELEMID_ERP:
614 			if (frm[1] != 1) {
615 				IEEE80211_DISCARD_IE(vap,
616 				    IEEE80211_MSG_ELEMID, wh, "ERP",
617 				    "bad len %u", frm[1]);
618 				vap->iv_stats.is_rx_elem_toobig++;
619 				break;
620 			}
621 			scan->erp = frm[2] | 0x100;
622 			break;
623 		case IEEE80211_ELEMID_HTCAP:
624 			scan->htcap = frm;
625 			break;
626 		case IEEE80211_ELEMID_VHT_CAP:
627 			scan->vhtcap = frm;
628 			break;
629 		case IEEE80211_ELEMID_VHT_OPMODE:
630 			scan->vhtopmode = frm;
631 			break;
632 		case IEEE80211_ELEMID_RSN:
633 			scan->rsn = frm;
634 			break;
635 		case IEEE80211_ELEMID_HTINFO:
636 			scan->htinfo = frm;
637 			break;
638 #ifdef IEEE80211_SUPPORT_MESH
639 		case IEEE80211_ELEMID_MESHID:
640 			scan->meshid = frm;
641 			break;
642 		case IEEE80211_ELEMID_MESHCONF:
643 			scan->meshconf = frm;
644 			break;
645 #endif
646 		/* Extended capabilities; nothing handles it for now */
647 		case IEEE80211_ELEMID_EXTCAP:
648 			break;
649 		case IEEE80211_ELEMID_VENDOR:
650 			if (iswpaoui(frm))
651 				scan->wpa = frm;
652 			else if (iswmeparam(frm) || iswmeinfo(frm))
653 				scan->wme = frm;
654 #ifdef IEEE80211_SUPPORT_SUPERG
655 			else if (isatherosoui(frm))
656 				scan->ath = frm;
657 #endif
658 #ifdef IEEE80211_SUPPORT_TDMA
659 			else if (istdmaoui(frm))
660 				scan->tdma = frm;
661 #endif
662 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
663 				/*
664 				 * Accept pre-draft HT ie's if the
665 				 * standard ones have not been seen.
666 				 */
667 				if (ishtcapoui(frm)) {
668 					if (scan->htcap == NULL)
669 						scan->htcap = frm;
670 				} else if (ishtinfooui(frm)) {
671 					if (scan->htinfo == NULL)
672 						scan->htcap = frm;
673 				}
674 			}
675 			break;
676 		default:
677 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
678 			    wh, "unhandled",
679 			    "id %u, len %u", *frm, frm[1]);
680 			vap->iv_stats.is_rx_elem_unknown++;
681 			break;
682 		}
683 		frm += frm[1] + 2;
684 	}
685 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
686 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
687 	if (scan->rates != NULL && scan->xrates != NULL) {
688 		/*
689 		 * NB: don't process XRATES if RATES is missing.  This
690 		 * avoids a potential null ptr deref and should be ok
691 		 * as the return code will already note RATES is missing
692 		 * (so callers shouldn't otherwise process the frame).
693 		 */
694 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
695 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
696 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
697 	}
698 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
699 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
700 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
701 		/*
702 		 * Frame was received on a channel different from the
703 		 * one indicated in the DS params element id;
704 		 * silently discard it.
705 		 *
706 		 * NB: this can happen due to signal leakage.
707 		 *     But we should take it for FH phy because
708 		 *     the rssi value should be correct even for
709 		 *     different hop pattern in FH.
710 		 */
711 		IEEE80211_DISCARD(vap,
712 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
713 		    wh, NULL, "for off-channel %u (bchan=%u)",
714 		    scan->chan, scan->bchan);
715 		vap->iv_stats.is_rx_chanmismatch++;
716 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
717 	}
718 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
719 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
720 		IEEE80211_DISCARD(vap,
721 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
722 		    wh, NULL, "bogus beacon interval (%d TU)",
723 		    (int) scan->bintval);
724 		vap->iv_stats.is_rx_badbintval++;
725 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
726 	}
727 	if (scan->country != NULL) {
728 		/*
729 		 * Validate we have at least enough data to extract
730 		 * the country code.  Not sure if we should return an
731 		 * error instead of discarding the IE; consider this
732 		 * being lenient as we don't depend on the data for
733 		 * correct operation.
734 		 */
735 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
736 		    scan->country = NULL);
737 	}
738 	if (scan->csa != NULL) {
739 		/*
740 		 * Validate Channel Switch Announcement; this must
741 		 * be the correct length or we toss the frame.
742 		 */
743 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
744 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
745 	}
746 #ifdef IEEE80211_SUPPORT_MESH
747 	if (scan->meshid != NULL) {
748 		IEEE80211_VERIFY_ELEMENT(scan->meshid, IEEE80211_MESHID_LEN,
749 		    scan->status |= IEEE80211_BPARSE_MESHID_INVALID);
750 	}
751 #endif
752 	/*
753 	 * Process HT ie's.  This is complicated by our
754 	 * accepting both the standard ie's and the pre-draft
755 	 * vendor OUI ie's that some vendors still use/require.
756 	 */
757 	if (scan->htcap != NULL) {
758 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
759 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
760 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
761 			 sizeof(struct ieee80211_ie_htcap)-2,
762 		     scan->htcap = NULL);
763 	}
764 	if (scan->htinfo != NULL) {
765 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
766 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
767 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
768 			 sizeof(struct ieee80211_ie_htinfo)-2,
769 		     scan->htinfo = NULL);
770 	}
771 
772 	/* Process VHT IEs */
773 	if (scan->vhtcap != NULL) {
774 		IEEE80211_VERIFY_LENGTH(scan->vhtcap[1],
775 		    sizeof(struct ieee80211_ie_vhtcap) - 2,
776 		    scan->vhtcap = NULL);
777 	}
778 	if (scan->vhtopmode != NULL) {
779 		IEEE80211_VERIFY_LENGTH(scan->vhtopmode[1],
780 		    sizeof(struct ieee80211_ie_vht_operation) - 2,
781 		    scan->vhtopmode = NULL);
782 	}
783 
784 	return scan->status;
785 }
786 
787 /*
788  * Parse an Action frame.  Return 0 on success, non-zero on failure.
789  */
790 int
791 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
792 {
793 	struct ieee80211vap *vap = ni->ni_vap;
794 	const struct ieee80211_action *ia;
795 	struct ieee80211_frame *wh;
796 	uint8_t *frm, *efrm;
797 
798 	/*
799 	 * action frame format:
800 	 *	[1] category
801 	 *	[1] action
802 	 *	[tlv] parameters
803 	 */
804 	wh = mtod(m, struct ieee80211_frame *);
805 	frm = (u_int8_t *)&wh[1];
806 	efrm = mtod(m, u_int8_t *) + m->m_len;
807 	IEEE80211_VERIFY_LENGTH(efrm - frm,
808 		sizeof(struct ieee80211_action), return EINVAL);
809 	ia = (const struct ieee80211_action *) frm;
810 
811 	vap->iv_stats.is_rx_action++;
812 	IEEE80211_NODE_STAT(ni, rx_action);
813 
814 	/* verify frame payloads but defer processing */
815 	switch (ia->ia_category) {
816 	case IEEE80211_ACTION_CAT_BA:
817 		switch (ia->ia_action) {
818 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
819 			IEEE80211_VERIFY_LENGTH(efrm - frm,
820 			    sizeof(struct ieee80211_action_ba_addbarequest),
821 			    return EINVAL);
822 			break;
823 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
824 			IEEE80211_VERIFY_LENGTH(efrm - frm,
825 			    sizeof(struct ieee80211_action_ba_addbaresponse),
826 			    return EINVAL);
827 			break;
828 		case IEEE80211_ACTION_BA_DELBA:
829 			IEEE80211_VERIFY_LENGTH(efrm - frm,
830 			    sizeof(struct ieee80211_action_ba_delba),
831 			    return EINVAL);
832 			break;
833 		}
834 		break;
835 	case IEEE80211_ACTION_CAT_HT:
836 		switch (ia->ia_action) {
837 		case IEEE80211_ACTION_HT_TXCHWIDTH:
838 			IEEE80211_VERIFY_LENGTH(efrm - frm,
839 			    sizeof(struct ieee80211_action_ht_txchwidth),
840 			    return EINVAL);
841 			break;
842 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
843 			IEEE80211_VERIFY_LENGTH(efrm - frm,
844 			    sizeof(struct ieee80211_action_ht_mimopowersave),
845 			    return EINVAL);
846 			break;
847 		}
848 		break;
849 #ifdef IEEE80211_SUPPORT_MESH
850 	case IEEE80211_ACTION_CAT_MESH:
851 		switch (ia->ia_action) {
852 		case IEEE80211_ACTION_MESH_LMETRIC:
853 			/*
854 			 * XXX: verification is true only if we are using
855 			 * Airtime link metric (default)
856 			 */
857 			IEEE80211_VERIFY_LENGTH(efrm - frm,
858 			    sizeof(struct ieee80211_meshlmetric_ie),
859 			    return EINVAL);
860 			break;
861 		case IEEE80211_ACTION_MESH_HWMP:
862 			/* verify something */
863 			break;
864 		case IEEE80211_ACTION_MESH_GANN:
865 			IEEE80211_VERIFY_LENGTH(efrm - frm,
866 			    sizeof(struct ieee80211_meshgann_ie),
867 			    return EINVAL);
868 			break;
869 		case IEEE80211_ACTION_MESH_CC:
870 		case IEEE80211_ACTION_MESH_MCCA_SREQ:
871 		case IEEE80211_ACTION_MESH_MCCA_SREP:
872 		case IEEE80211_ACTION_MESH_MCCA_AREQ:
873 		case IEEE80211_ACTION_MESH_MCCA_ADVER:
874 		case IEEE80211_ACTION_MESH_MCCA_TRDOWN:
875 		case IEEE80211_ACTION_MESH_TBTT_REQ:
876 		case IEEE80211_ACTION_MESH_TBTT_RES:
877 			/* reject these early on, not implemented */
878 			IEEE80211_DISCARD(vap,
879 			    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
880 			    wh, NULL, "not implemented yet, act=0x%02X",
881 			    ia->ia_action);
882 			return EINVAL;
883 		}
884 		break;
885 	case IEEE80211_ACTION_CAT_SELF_PROT:
886 		/* If TA or RA group address discard silently */
887 		if (IEEE80211_IS_MULTICAST(wh->i_addr1) ||
888 			IEEE80211_IS_MULTICAST(wh->i_addr2))
889 			return EINVAL;
890 		/*
891 		 * XXX: Should we verify complete length now or it is
892 		 * to varying in sizes?
893 		 */
894 		switch (ia->ia_action) {
895 		case IEEE80211_ACTION_MESHPEERING_CONFIRM:
896 		case IEEE80211_ACTION_MESHPEERING_CLOSE:
897 			/* is not a peering candidate (yet) */
898 			if (ni == vap->iv_bss)
899 				return EINVAL;
900 			break;
901 		}
902 		break;
903 #endif
904 	case IEEE80211_ACTION_CAT_VHT:
905 		printf("%s: TODO: VHT handling!\n", __func__);
906 		break;
907 	}
908 	return 0;
909 }
910 
911 #ifdef IEEE80211_DEBUG
912 /*
913  * Debugging support.
914  */
915 void
916 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
917 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
918 {
919 	printf("[%s] discard %s frame, ssid mismatch: ",
920 		ether_sprintf(mac), tag);
921 	ieee80211_print_essid(ssid + 2, ssid[1]);
922 	printf("\n");
923 }
924 
925 /*
926  * Return the bssid of a frame.
927  */
928 static const uint8_t *
929 ieee80211_getbssid(const struct ieee80211vap *vap,
930 	const struct ieee80211_frame *wh)
931 {
932 	if (vap->iv_opmode == IEEE80211_M_STA)
933 		return wh->i_addr2;
934 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
935 		return wh->i_addr1;
936 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
937 		return wh->i_addr1;
938 	return wh->i_addr3;
939 }
940 
941 #include <machine/stdarg.h>
942 
943 void
944 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
945 {
946 	char buf[256];		/* XXX */
947 	va_list ap;
948 	int len;
949 
950 	va_start(ap, fmt);
951 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
952 	va_end(ap);
953 
954 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
955 
956 	if (len >= sizeof(buf))
957 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
958 }
959 
960 void
961 ieee80211_note_frame(const struct ieee80211vap *vap,
962 	const struct ieee80211_frame *wh,
963 	const char *fmt, ...)
964 {
965 	char buf[256];		/* XXX */
966 	va_list ap;
967 	int len;
968 
969 	va_start(ap, fmt);
970 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
971 	va_end(ap);
972 	if_printf(vap->iv_ifp, "[%s] %s\n",
973 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
974 
975 	if (len >= sizeof(buf))
976 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
977 }
978 
979 void
980 ieee80211_note_mac(const struct ieee80211vap *vap,
981 	const uint8_t mac[IEEE80211_ADDR_LEN],
982 	const char *fmt, ...)
983 {
984 	char buf[256];		/* XXX */
985 	va_list ap;
986 	int len;
987 
988 	va_start(ap, fmt);
989 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
990 	va_end(ap);
991 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
992 
993 	if (len >= sizeof(buf))
994 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
995 }
996 
997 void
998 ieee80211_discard_frame(const struct ieee80211vap *vap,
999 	const struct ieee80211_frame *wh,
1000 	const char *type, const char *fmt, ...)
1001 {
1002 	char buf[256];		/* XXX */
1003 	va_list ap;
1004 	int len;
1005 
1006 	va_start(ap, fmt);
1007 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1008 	va_end(ap);
1009 
1010 	if_printf(vap->iv_ifp, "[%s] discard %s frame, %s\n",
1011 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1012 	    type != NULL ? type : ieee80211_mgt_subtype_name(wh->i_fc[0]),
1013 	    buf);
1014 
1015 	if (len >= sizeof(buf))
1016 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1017 }
1018 
1019 void
1020 ieee80211_discard_ie(const struct ieee80211vap *vap,
1021 	const struct ieee80211_frame *wh,
1022 	const char *type, const char *fmt, ...)
1023 {
1024 	char buf[256];		/* XXX */
1025 	va_list ap;
1026 	int len;
1027 
1028 	va_start(ap, fmt);
1029 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1030 	va_end(ap);
1031 
1032 	if_printf(vap->iv_ifp, "[%s] discard%s%s information element, %s\n",
1033 	    ether_sprintf(ieee80211_getbssid(vap, wh)),
1034 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1035 
1036 	if (len >= sizeof(buf))
1037 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1038 }
1039 
1040 void
1041 ieee80211_discard_mac(const struct ieee80211vap *vap,
1042 	const uint8_t mac[IEEE80211_ADDR_LEN],
1043 	const char *type, const char *fmt, ...)
1044 {
1045 	char buf[256];		/* XXX */
1046 	va_list ap;
1047 	int len;
1048 
1049 	va_start(ap, fmt);
1050 	len = vsnprintf(buf, sizeof(buf), fmt, ap);
1051 	va_end(ap);
1052 
1053 	if_printf(vap->iv_ifp, "[%s] discard%s%s frame, %s\n",
1054 	    ether_sprintf(mac),
1055 	    type != NULL ? " " : "", type != NULL ? type : "", buf);
1056 
1057 	if (len >= sizeof(buf))
1058 		printf("%s: XXX buffer too small: len = %d\n", __func__, len);
1059 }
1060 #endif /* IEEE80211_DEBUG */
1061