xref: /freebsd/sys/net80211/ieee80211_input.c (revision 10b59a9b4add0320d52c15ce057dd697261e7dfc)
1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_wlan.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/mbuf.h>
35 #include <sys/malloc.h>
36 #include <sys/endian.h>
37 #include <sys/kernel.h>
38 
39 #include <sys/socket.h>
40 
41 #include <net/ethernet.h>
42 #include <net/if.h>
43 #include <net/if_llc.h>
44 #include <net/if_media.h>
45 #include <net/if_vlan_var.h>
46 
47 #include <net80211/ieee80211_var.h>
48 #include <net80211/ieee80211_input.h>
49 #ifdef IEEE80211_SUPPORT_MESH
50 #include <net80211/ieee80211_mesh.h>
51 #endif
52 
53 #include <net/bpf.h>
54 
55 #ifdef INET
56 #include <netinet/in.h>
57 #include <net/ethernet.h>
58 #endif
59 
60 static void
61 ieee80211_process_mimo(struct ieee80211_node *ni, struct ieee80211_rx_stats *rx)
62 {
63 	int i;
64 
65 	/* Verify the required MIMO bits are set */
66 	if ((rx->r_flags & (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI)) !=
67 	    (IEEE80211_R_C_CHAIN | IEEE80211_R_C_NF | IEEE80211_R_C_RSSI))
68 		return;
69 
70 	/* XXX This assumes the MIMO radios have both ctl and ext chains */
71 	for (i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
72 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ctl[i], rx->c_rssi_ctl[i]);
73 		IEEE80211_RSSI_LPF(ni->ni_mimo_rssi_ext[i], rx->c_rssi_ext[i]);
74 	}
75 
76 	/* XXX This also assumes the MIMO radios have both ctl and ext chains */
77 	for(i = 0; i < MIN(rx->c_chain, IEEE80211_MAX_CHAINS); i++) {
78 		ni->ni_mimo_noise_ctl[i] = rx->c_nf_ctl[i];
79 		ni->ni_mimo_noise_ext[i] = rx->c_nf_ext[i];
80 	}
81 	ni->ni_mimo_chains = rx->c_chain;
82 }
83 
84 int
85 ieee80211_input_mimo(struct ieee80211_node *ni, struct mbuf *m,
86     struct ieee80211_rx_stats *rx)
87 {
88 	/* XXX should assert IEEE80211_R_NF and IEEE80211_R_RSSI are set */
89 	ieee80211_process_mimo(ni, rx);
90 	return ieee80211_input(ni, m, rx->rssi, rx->nf);
91 }
92 
93 int
94 ieee80211_input_all(struct ieee80211com *ic, struct mbuf *m, int rssi, int nf)
95 {
96 	struct ieee80211_rx_stats rx;
97 
98 	rx.r_flags = IEEE80211_R_NF | IEEE80211_R_RSSI;
99 	rx.nf = nf;
100 	rx.rssi = rssi;
101 	return ieee80211_input_mimo_all(ic, m, &rx);
102 }
103 
104 int
105 ieee80211_input_mimo_all(struct ieee80211com *ic, struct mbuf *m,
106     struct ieee80211_rx_stats *rx)
107 {
108 	struct ieee80211vap *vap;
109 	int type = -1;
110 
111 	m->m_flags |= M_BCAST;		/* NB: mark for bpf tap'ing */
112 
113 	/* XXX locking */
114 	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
115 		struct ieee80211_node *ni;
116 		struct mbuf *mcopy;
117 
118 		/* NB: could check for IFF_UP but this is cheaper */
119 		if (vap->iv_state == IEEE80211_S_INIT)
120 			continue;
121 		/*
122 		 * WDS vap's only receive directed traffic from the
123 		 * station at the ``far end''.  That traffic should
124 		 * be passed through the AP vap the station is associated
125 		 * to--so don't spam them with mcast frames.
126 		 */
127 		if (vap->iv_opmode == IEEE80211_M_WDS)
128 			continue;
129 		if (TAILQ_NEXT(vap, iv_next) != NULL) {
130 			/*
131 			 * Packet contents are changed by ieee80211_decap
132 			 * so do a deep copy of the packet.
133 			 */
134 			mcopy = m_dup(m, M_DONTWAIT);
135 			if (mcopy == NULL) {
136 				/* XXX stat+msg */
137 				continue;
138 			}
139 		} else {
140 			mcopy = m;
141 			m = NULL;
142 		}
143 		ni = ieee80211_ref_node(vap->iv_bss);
144 		type = ieee80211_input_mimo(ni, mcopy, rx);
145 		ieee80211_free_node(ni);
146 	}
147 	if (m != NULL)			/* no vaps, reclaim mbuf */
148 		m_freem(m);
149 	return type;
150 }
151 
152 /*
153  * This function reassembles fragments.
154  *
155  * XXX should handle 3 concurrent reassemblies per-spec.
156  */
157 struct mbuf *
158 ieee80211_defrag(struct ieee80211_node *ni, struct mbuf *m, int hdrspace)
159 {
160 	struct ieee80211vap *vap = ni->ni_vap;
161 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
162 	struct ieee80211_frame *lwh;
163 	uint16_t rxseq;
164 	uint8_t fragno;
165 	uint8_t more_frag = wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG;
166 	struct mbuf *mfrag;
167 
168 	KASSERT(!IEEE80211_IS_MULTICAST(wh->i_addr1), ("multicast fragm?"));
169 
170 	rxseq = le16toh(*(uint16_t *)wh->i_seq);
171 	fragno = rxseq & IEEE80211_SEQ_FRAG_MASK;
172 
173 	/* Quick way out, if there's nothing to defragment */
174 	if (!more_frag && fragno == 0 && ni->ni_rxfrag[0] == NULL)
175 		return m;
176 
177 	/*
178 	 * Remove frag to insure it doesn't get reaped by timer.
179 	 */
180 	if (ni->ni_table == NULL) {
181 		/*
182 		 * Should never happen.  If the node is orphaned (not in
183 		 * the table) then input packets should not reach here.
184 		 * Otherwise, a concurrent request that yanks the table
185 		 * should be blocked by other interlocking and/or by first
186 		 * shutting the driver down.  Regardless, be defensive
187 		 * here and just bail
188 		 */
189 		/* XXX need msg+stat */
190 		m_freem(m);
191 		return NULL;
192 	}
193 	IEEE80211_NODE_LOCK(ni->ni_table);
194 	mfrag = ni->ni_rxfrag[0];
195 	ni->ni_rxfrag[0] = NULL;
196 	IEEE80211_NODE_UNLOCK(ni->ni_table);
197 
198 	/*
199 	 * Validate new fragment is in order and
200 	 * related to the previous ones.
201 	 */
202 	if (mfrag != NULL) {
203 		uint16_t last_rxseq;
204 
205 		lwh = mtod(mfrag, struct ieee80211_frame *);
206 		last_rxseq = le16toh(*(uint16_t *)lwh->i_seq);
207 		/* NB: check seq # and frag together */
208 		if (rxseq != last_rxseq+1 ||
209 		    !IEEE80211_ADDR_EQ(wh->i_addr1, lwh->i_addr1) ||
210 		    !IEEE80211_ADDR_EQ(wh->i_addr2, lwh->i_addr2)) {
211 			/*
212 			 * Unrelated fragment or no space for it,
213 			 * clear current fragments.
214 			 */
215 			m_freem(mfrag);
216 			mfrag = NULL;
217 		}
218 	}
219 
220  	if (mfrag == NULL) {
221 		if (fragno != 0) {		/* !first fragment, discard */
222 			vap->iv_stats.is_rx_defrag++;
223 			IEEE80211_NODE_STAT(ni, rx_defrag);
224 			m_freem(m);
225 			return NULL;
226 		}
227 		mfrag = m;
228 	} else {				/* concatenate */
229 		m_adj(m, hdrspace);		/* strip header */
230 		m_cat(mfrag, m);
231 		/* NB: m_cat doesn't update the packet header */
232 		mfrag->m_pkthdr.len += m->m_pkthdr.len;
233 		/* track last seqnum and fragno */
234 		lwh = mtod(mfrag, struct ieee80211_frame *);
235 		*(uint16_t *) lwh->i_seq = *(uint16_t *) wh->i_seq;
236 	}
237 	if (more_frag) {			/* more to come, save */
238 		ni->ni_rxfragstamp = ticks;
239 		ni->ni_rxfrag[0] = mfrag;
240 		mfrag = NULL;
241 	}
242 	return mfrag;
243 }
244 
245 void
246 ieee80211_deliver_data(struct ieee80211vap *vap,
247 	struct ieee80211_node *ni, struct mbuf *m)
248 {
249 	struct ether_header *eh = mtod(m, struct ether_header *);
250 	struct ifnet *ifp = vap->iv_ifp;
251 
252 	/* clear driver/net80211 flags before passing up */
253 	m->m_flags &= ~(M_80211_RX | M_MCAST | M_BCAST);
254 
255 	/* NB: see hostap_deliver_data, this path doesn't handle hostap */
256 	KASSERT(vap->iv_opmode != IEEE80211_M_HOSTAP, ("gack, hostap"));
257 	/*
258 	 * Do accounting.
259 	 */
260 	ifp->if_ipackets++;
261 	IEEE80211_NODE_STAT(ni, rx_data);
262 	IEEE80211_NODE_STAT_ADD(ni, rx_bytes, m->m_pkthdr.len);
263 	if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
264 		m->m_flags |= M_MCAST;		/* XXX M_BCAST? */
265 		IEEE80211_NODE_STAT(ni, rx_mcast);
266 	} else
267 		IEEE80211_NODE_STAT(ni, rx_ucast);
268 	m->m_pkthdr.rcvif = ifp;
269 
270 	if (ni->ni_vlan != 0) {
271 		/* attach vlan tag */
272 		m->m_pkthdr.ether_vtag = ni->ni_vlan;
273 		m->m_flags |= M_VLANTAG;
274 	}
275 	ifp->if_input(ifp, m);
276 }
277 
278 struct mbuf *
279 ieee80211_decap(struct ieee80211vap *vap, struct mbuf *m, int hdrlen)
280 {
281 	struct ieee80211_qosframe_addr4 wh;
282 	struct ether_header *eh;
283 	struct llc *llc;
284 
285 	KASSERT(hdrlen <= sizeof(wh),
286 	    ("hdrlen %d > max %zd", hdrlen, sizeof(wh)));
287 
288 	if (m->m_len < hdrlen + sizeof(*llc) &&
289 	    (m = m_pullup(m, hdrlen + sizeof(*llc))) == NULL) {
290 		vap->iv_stats.is_rx_tooshort++;
291 		/* XXX msg */
292 		return NULL;
293 	}
294 	memcpy(&wh, mtod(m, caddr_t), hdrlen);
295 	llc = (struct llc *)(mtod(m, caddr_t) + hdrlen);
296 	if (llc->llc_dsap == LLC_SNAP_LSAP && llc->llc_ssap == LLC_SNAP_LSAP &&
297 	    llc->llc_control == LLC_UI && llc->llc_snap.org_code[0] == 0 &&
298 	    llc->llc_snap.org_code[1] == 0 && llc->llc_snap.org_code[2] == 0 &&
299 	    /* NB: preserve AppleTalk frames that have a native SNAP hdr */
300 	    !(llc->llc_snap.ether_type == htons(ETHERTYPE_AARP) ||
301 	      llc->llc_snap.ether_type == htons(ETHERTYPE_IPX))) {
302 		m_adj(m, hdrlen + sizeof(struct llc) - sizeof(*eh));
303 		llc = NULL;
304 	} else {
305 		m_adj(m, hdrlen - sizeof(*eh));
306 	}
307 	eh = mtod(m, struct ether_header *);
308 	switch (wh.i_fc[1] & IEEE80211_FC1_DIR_MASK) {
309 	case IEEE80211_FC1_DIR_NODS:
310 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
311 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
312 		break;
313 	case IEEE80211_FC1_DIR_TODS:
314 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
315 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr2);
316 		break;
317 	case IEEE80211_FC1_DIR_FROMDS:
318 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr1);
319 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr3);
320 		break;
321 	case IEEE80211_FC1_DIR_DSTODS:
322 		IEEE80211_ADDR_COPY(eh->ether_dhost, wh.i_addr3);
323 		IEEE80211_ADDR_COPY(eh->ether_shost, wh.i_addr4);
324 		break;
325 	}
326 #ifdef ALIGNED_POINTER
327 	if (!ALIGNED_POINTER(mtod(m, caddr_t) + sizeof(*eh), uint32_t)) {
328 		m = ieee80211_realign(vap, m, sizeof(*eh));
329 		if (m == NULL)
330 			return NULL;
331 	}
332 #endif /* ALIGNED_POINTER */
333 	if (llc != NULL) {
334 		eh = mtod(m, struct ether_header *);
335 		eh->ether_type = htons(m->m_pkthdr.len - sizeof(*eh));
336 	}
337 	return m;
338 }
339 
340 /*
341  * Decap a frame encapsulated in a fast-frame/A-MSDU.
342  */
343 struct mbuf *
344 ieee80211_decap1(struct mbuf *m, int *framelen)
345 {
346 #define	FF_LLC_SIZE	(sizeof(struct ether_header) + sizeof(struct llc))
347 	struct ether_header *eh;
348 	struct llc *llc;
349 
350 	/*
351 	 * The frame has an 802.3 header followed by an 802.2
352 	 * LLC header.  The encapsulated frame length is in the
353 	 * first header type field; save that and overwrite it
354 	 * with the true type field found in the second.  Then
355 	 * copy the 802.3 header up to where it belongs and
356 	 * adjust the mbuf contents to remove the void.
357 	 */
358 	if (m->m_len < FF_LLC_SIZE && (m = m_pullup(m, FF_LLC_SIZE)) == NULL)
359 		return NULL;
360 	eh = mtod(m, struct ether_header *);	/* 802.3 header is first */
361 	llc = (struct llc *)&eh[1];		/* 802.2 header follows */
362 	*framelen = ntohs(eh->ether_type)	/* encap'd frame size */
363 		  + sizeof(struct ether_header) - sizeof(struct llc);
364 	eh->ether_type = llc->llc_un.type_snap.ether_type;
365 	ovbcopy(eh, mtod(m, uint8_t *) + sizeof(struct llc),
366 		sizeof(struct ether_header));
367 	m_adj(m, sizeof(struct llc));
368 	return m;
369 #undef FF_LLC_SIZE
370 }
371 
372 /*
373  * Install received rate set information in the node's state block.
374  */
375 int
376 ieee80211_setup_rates(struct ieee80211_node *ni,
377 	const uint8_t *rates, const uint8_t *xrates, int flags)
378 {
379 	struct ieee80211vap *vap = ni->ni_vap;
380 	struct ieee80211_rateset *rs = &ni->ni_rates;
381 
382 	memset(rs, 0, sizeof(*rs));
383 	rs->rs_nrates = rates[1];
384 	memcpy(rs->rs_rates, rates + 2, rs->rs_nrates);
385 	if (xrates != NULL) {
386 		uint8_t nxrates;
387 		/*
388 		 * Tack on 11g extended supported rate element.
389 		 */
390 		nxrates = xrates[1];
391 		if (rs->rs_nrates + nxrates > IEEE80211_RATE_MAXSIZE) {
392 			nxrates = IEEE80211_RATE_MAXSIZE - rs->rs_nrates;
393 			IEEE80211_NOTE(vap, IEEE80211_MSG_XRATE, ni,
394 			    "extended rate set too large; only using "
395 			    "%u of %u rates", nxrates, xrates[1]);
396 			vap->iv_stats.is_rx_rstoobig++;
397 		}
398 		memcpy(rs->rs_rates + rs->rs_nrates, xrates+2, nxrates);
399 		rs->rs_nrates += nxrates;
400 	}
401 	return ieee80211_fix_rate(ni, rs, flags);
402 }
403 
404 /*
405  * Send a management frame error response to the specified
406  * station.  If ni is associated with the station then use
407  * it; otherwise allocate a temporary node suitable for
408  * transmitting the frame and then free the reference so
409  * it will go away as soon as the frame has been transmitted.
410  */
411 void
412 ieee80211_send_error(struct ieee80211_node *ni,
413 	const uint8_t mac[IEEE80211_ADDR_LEN], int subtype, int arg)
414 {
415 	struct ieee80211vap *vap = ni->ni_vap;
416 	int istmp;
417 
418 	if (ni == vap->iv_bss) {
419 		if (vap->iv_state != IEEE80211_S_RUN) {
420 			/*
421 			 * XXX hack until we get rid of this routine.
422 			 * We can be called prior to the vap reaching
423 			 * run state under certain conditions in which
424 			 * case iv_bss->ni_chan will not be setup.
425 			 * Check for this explicitly and and just ignore
426 			 * the request.
427 			 */
428 			return;
429 		}
430 		ni = ieee80211_tmp_node(vap, mac);
431 		if (ni == NULL) {
432 			/* XXX msg */
433 			return;
434 		}
435 		istmp = 1;
436 	} else
437 		istmp = 0;
438 	IEEE80211_SEND_MGMT(ni, subtype, arg);
439 	if (istmp)
440 		ieee80211_free_node(ni);
441 }
442 
443 int
444 ieee80211_alloc_challenge(struct ieee80211_node *ni)
445 {
446 	if (ni->ni_challenge == NULL)
447 		ni->ni_challenge = (uint32_t *) malloc(IEEE80211_CHALLENGE_LEN,
448 		    M_80211_NODE, M_NOWAIT);
449 	if (ni->ni_challenge == NULL) {
450 		IEEE80211_NOTE(ni->ni_vap,
451 		    IEEE80211_MSG_DEBUG | IEEE80211_MSG_AUTH, ni,
452 		    "%s", "shared key challenge alloc failed");
453 		/* XXX statistic */
454 	}
455 	return (ni->ni_challenge != NULL);
456 }
457 
458 /*
459  * Parse a Beacon or ProbeResponse frame and return the
460  * useful information in an ieee80211_scanparams structure.
461  * Status is set to 0 if no problems were found; otherwise
462  * a bitmask of IEEE80211_BPARSE_* items is returned that
463  * describes the problems detected.
464  */
465 int
466 ieee80211_parse_beacon(struct ieee80211_node *ni, struct mbuf *m,
467 	struct ieee80211_scanparams *scan)
468 {
469 	struct ieee80211vap *vap = ni->ni_vap;
470 	struct ieee80211com *ic = ni->ni_ic;
471 	struct ieee80211_frame *wh;
472 	uint8_t *frm, *efrm;
473 
474 	wh = mtod(m, struct ieee80211_frame *);
475 	frm = (uint8_t *)&wh[1];
476 	efrm = mtod(m, uint8_t *) + m->m_len;
477 	scan->status = 0;
478 	/*
479 	 * beacon/probe response frame format
480 	 *	[8] time stamp
481 	 *	[2] beacon interval
482 	 *	[2] capability information
483 	 *	[tlv] ssid
484 	 *	[tlv] supported rates
485 	 *	[tlv] country information
486 	 *	[tlv] channel switch announcement (CSA)
487 	 *	[tlv] parameter set (FH/DS)
488 	 *	[tlv] erp information
489 	 *	[tlv] extended supported rates
490 	 *	[tlv] WME
491 	 *	[tlv] WPA or RSN
492 	 *	[tlv] HT capabilities
493 	 *	[tlv] HT information
494 	 *	[tlv] Atheros capabilities
495 	 *	[tlv] Mesh ID
496 	 *	[tlv] Mesh Configuration
497 	 */
498 	IEEE80211_VERIFY_LENGTH(efrm - frm, 12,
499 	    return (scan->status = IEEE80211_BPARSE_BADIELEN));
500 	memset(scan, 0, sizeof(*scan));
501 	scan->tstamp  = frm;				frm += 8;
502 	scan->bintval = le16toh(*(uint16_t *)frm);	frm += 2;
503 	scan->capinfo = le16toh(*(uint16_t *)frm);	frm += 2;
504 	scan->bchan = ieee80211_chan2ieee(ic, ic->ic_curchan);
505 	scan->chan = scan->bchan;
506 	scan->ies = frm;
507 	scan->ies_len = efrm - frm;
508 
509 	while (efrm - frm > 1) {
510 		IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2,
511 		    return (scan->status = IEEE80211_BPARSE_BADIELEN));
512 		switch (*frm) {
513 		case IEEE80211_ELEMID_SSID:
514 			scan->ssid = frm;
515 			break;
516 		case IEEE80211_ELEMID_RATES:
517 			scan->rates = frm;
518 			break;
519 		case IEEE80211_ELEMID_COUNTRY:
520 			scan->country = frm;
521 			break;
522 		case IEEE80211_ELEMID_CSA:
523 			scan->csa = frm;
524 			break;
525 		case IEEE80211_ELEMID_QUIET:
526 			scan->quiet = frm;
527 			break;
528 		case IEEE80211_ELEMID_FHPARMS:
529 			if (ic->ic_phytype == IEEE80211_T_FH) {
530 				scan->fhdwell = LE_READ_2(&frm[2]);
531 				scan->chan = IEEE80211_FH_CHAN(frm[4], frm[5]);
532 				scan->fhindex = frm[6];
533 			}
534 			break;
535 		case IEEE80211_ELEMID_DSPARMS:
536 			/*
537 			 * XXX hack this since depending on phytype
538 			 * is problematic for multi-mode devices.
539 			 */
540 			if (ic->ic_phytype != IEEE80211_T_FH)
541 				scan->chan = frm[2];
542 			break;
543 		case IEEE80211_ELEMID_TIM:
544 			/* XXX ATIM? */
545 			scan->tim = frm;
546 			scan->timoff = frm - mtod(m, uint8_t *);
547 			break;
548 		case IEEE80211_ELEMID_IBSSPARMS:
549 		case IEEE80211_ELEMID_CFPARMS:
550 		case IEEE80211_ELEMID_PWRCNSTR:
551 			/* NB: avoid debugging complaints */
552 			break;
553 		case IEEE80211_ELEMID_XRATES:
554 			scan->xrates = frm;
555 			break;
556 		case IEEE80211_ELEMID_ERP:
557 			if (frm[1] != 1) {
558 				IEEE80211_DISCARD_IE(vap,
559 				    IEEE80211_MSG_ELEMID, wh, "ERP",
560 				    "bad len %u", frm[1]);
561 				vap->iv_stats.is_rx_elem_toobig++;
562 				break;
563 			}
564 			scan->erp = frm[2] | 0x100;
565 			break;
566 		case IEEE80211_ELEMID_HTCAP:
567 			scan->htcap = frm;
568 			break;
569 		case IEEE80211_ELEMID_RSN:
570 			scan->rsn = frm;
571 			break;
572 		case IEEE80211_ELEMID_HTINFO:
573 			scan->htinfo = frm;
574 			break;
575 #ifdef IEEE80211_SUPPORT_MESH
576 		case IEEE80211_ELEMID_MESHID:
577 			scan->meshid = frm;
578 			break;
579 		case IEEE80211_ELEMID_MESHCONF:
580 			scan->meshconf = frm;
581 			break;
582 #endif
583 		case IEEE80211_ELEMID_VENDOR:
584 			if (iswpaoui(frm))
585 				scan->wpa = frm;
586 			else if (iswmeparam(frm) || iswmeinfo(frm))
587 				scan->wme = frm;
588 #ifdef IEEE80211_SUPPORT_SUPERG
589 			else if (isatherosoui(frm))
590 				scan->ath = frm;
591 #endif
592 #ifdef IEEE80211_SUPPORT_TDMA
593 			else if (istdmaoui(frm))
594 				scan->tdma = frm;
595 #endif
596 			else if (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) {
597 				/*
598 				 * Accept pre-draft HT ie's if the
599 				 * standard ones have not been seen.
600 				 */
601 				if (ishtcapoui(frm)) {
602 					if (scan->htcap == NULL)
603 						scan->htcap = frm;
604 				} else if (ishtinfooui(frm)) {
605 					if (scan->htinfo == NULL)
606 						scan->htcap = frm;
607 				}
608 			}
609 			break;
610 		default:
611 			IEEE80211_DISCARD_IE(vap, IEEE80211_MSG_ELEMID,
612 			    wh, "unhandled",
613 			    "id %u, len %u", *frm, frm[1]);
614 			vap->iv_stats.is_rx_elem_unknown++;
615 			break;
616 		}
617 		frm += frm[1] + 2;
618 	}
619 	IEEE80211_VERIFY_ELEMENT(scan->rates, IEEE80211_RATE_MAXSIZE,
620 	    scan->status |= IEEE80211_BPARSE_RATES_INVALID);
621 	if (scan->rates != NULL && scan->xrates != NULL) {
622 		/*
623 		 * NB: don't process XRATES if RATES is missing.  This
624 		 * avoids a potential null ptr deref and should be ok
625 		 * as the return code will already note RATES is missing
626 		 * (so callers shouldn't otherwise process the frame).
627 		 */
628 		IEEE80211_VERIFY_ELEMENT(scan->xrates,
629 		    IEEE80211_RATE_MAXSIZE - scan->rates[1],
630 		    scan->status |= IEEE80211_BPARSE_XRATES_INVALID);
631 	}
632 	IEEE80211_VERIFY_ELEMENT(scan->ssid, IEEE80211_NWID_LEN,
633 	    scan->status |= IEEE80211_BPARSE_SSID_INVALID);
634 	if (scan->chan != scan->bchan && ic->ic_phytype != IEEE80211_T_FH) {
635 		/*
636 		 * Frame was received on a channel different from the
637 		 * one indicated in the DS params element id;
638 		 * silently discard it.
639 		 *
640 		 * NB: this can happen due to signal leakage.
641 		 *     But we should take it for FH phy because
642 		 *     the rssi value should be correct even for
643 		 *     different hop pattern in FH.
644 		 */
645 		IEEE80211_DISCARD(vap,
646 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
647 		    wh, NULL, "for off-channel %u", scan->chan);
648 		vap->iv_stats.is_rx_chanmismatch++;
649 		scan->status |= IEEE80211_BPARSE_OFFCHAN;
650 	}
651 	if (!(IEEE80211_BINTVAL_MIN <= scan->bintval &&
652 	      scan->bintval <= IEEE80211_BINTVAL_MAX)) {
653 		IEEE80211_DISCARD(vap,
654 		    IEEE80211_MSG_ELEMID | IEEE80211_MSG_INPUT,
655 		    wh, NULL, "bogus beacon interval", scan->bintval);
656 		vap->iv_stats.is_rx_badbintval++;
657 		scan->status |= IEEE80211_BPARSE_BINTVAL_INVALID;
658 	}
659 	if (scan->country != NULL) {
660 		/*
661 		 * Validate we have at least enough data to extract
662 		 * the country code.  Not sure if we should return an
663 		 * error instead of discarding the IE; consider this
664 		 * being lenient as we don't depend on the data for
665 		 * correct operation.
666 		 */
667 		IEEE80211_VERIFY_LENGTH(scan->country[1], 3 * sizeof(uint8_t),
668 		    scan->country = NULL);
669 	}
670 	if (scan->csa != NULL) {
671 		/*
672 		 * Validate Channel Switch Announcement; this must
673 		 * be the correct length or we toss the frame.
674 		 */
675 		IEEE80211_VERIFY_LENGTH(scan->csa[1], 3 * sizeof(uint8_t),
676 		    scan->status |= IEEE80211_BPARSE_CSA_INVALID);
677 	}
678 	/*
679 	 * Process HT ie's.  This is complicated by our
680 	 * accepting both the standard ie's and the pre-draft
681 	 * vendor OUI ie's that some vendors still use/require.
682 	 */
683 	if (scan->htcap != NULL) {
684 		IEEE80211_VERIFY_LENGTH(scan->htcap[1],
685 		     scan->htcap[0] == IEEE80211_ELEMID_VENDOR ?
686 			 4 + sizeof(struct ieee80211_ie_htcap)-2 :
687 			 sizeof(struct ieee80211_ie_htcap)-2,
688 		     scan->htcap = NULL);
689 	}
690 	if (scan->htinfo != NULL) {
691 		IEEE80211_VERIFY_LENGTH(scan->htinfo[1],
692 		     scan->htinfo[0] == IEEE80211_ELEMID_VENDOR ?
693 			 4 + sizeof(struct ieee80211_ie_htinfo)-2 :
694 			 sizeof(struct ieee80211_ie_htinfo)-2,
695 		     scan->htinfo = NULL);
696 	}
697 	return scan->status;
698 }
699 
700 /*
701  * Parse an Action frame.  Return 0 on success, non-zero on failure.
702  */
703 int
704 ieee80211_parse_action(struct ieee80211_node *ni, struct mbuf *m)
705 {
706 	struct ieee80211vap *vap = ni->ni_vap;
707 	const struct ieee80211_action *ia;
708 	struct ieee80211_frame *wh;
709 	uint8_t *frm, *efrm;
710 
711 	/*
712 	 * action frame format:
713 	 *	[1] category
714 	 *	[1] action
715 	 *	[tlv] parameters
716 	 */
717 	wh = mtod(m, struct ieee80211_frame *);
718 	frm = (u_int8_t *)&wh[1];
719 	efrm = mtod(m, u_int8_t *) + m->m_len;
720 	IEEE80211_VERIFY_LENGTH(efrm - frm,
721 		sizeof(struct ieee80211_action), return EINVAL);
722 	ia = (const struct ieee80211_action *) frm;
723 
724 	vap->iv_stats.is_rx_action++;
725 	IEEE80211_NODE_STAT(ni, rx_action);
726 
727 	/* verify frame payloads but defer processing */
728 	switch (ia->ia_category) {
729 	case IEEE80211_ACTION_CAT_BA:
730 		switch (ia->ia_action) {
731 		case IEEE80211_ACTION_BA_ADDBA_REQUEST:
732 			IEEE80211_VERIFY_LENGTH(efrm - frm,
733 			    sizeof(struct ieee80211_action_ba_addbarequest),
734 			    return EINVAL);
735 			break;
736 		case IEEE80211_ACTION_BA_ADDBA_RESPONSE:
737 			IEEE80211_VERIFY_LENGTH(efrm - frm,
738 			    sizeof(struct ieee80211_action_ba_addbaresponse),
739 			    return EINVAL);
740 			break;
741 		case IEEE80211_ACTION_BA_DELBA:
742 			IEEE80211_VERIFY_LENGTH(efrm - frm,
743 			    sizeof(struct ieee80211_action_ba_delba),
744 			    return EINVAL);
745 			break;
746 		}
747 		break;
748 	case IEEE80211_ACTION_CAT_HT:
749 		switch (ia->ia_action) {
750 		case IEEE80211_ACTION_HT_TXCHWIDTH:
751 			IEEE80211_VERIFY_LENGTH(efrm - frm,
752 			    sizeof(struct ieee80211_action_ht_txchwidth),
753 			    return EINVAL);
754 			break;
755 		case IEEE80211_ACTION_HT_MIMOPWRSAVE:
756 			IEEE80211_VERIFY_LENGTH(efrm - frm,
757 			    sizeof(struct ieee80211_action_ht_mimopowersave),
758 			    return EINVAL);
759 			break;
760 		}
761 		break;
762 	}
763 	return 0;
764 }
765 
766 #ifdef IEEE80211_DEBUG
767 /*
768  * Debugging support.
769  */
770 void
771 ieee80211_ssid_mismatch(struct ieee80211vap *vap, const char *tag,
772 	uint8_t mac[IEEE80211_ADDR_LEN], uint8_t *ssid)
773 {
774 	printf("[%s] discard %s frame, ssid mismatch: ",
775 		ether_sprintf(mac), tag);
776 	ieee80211_print_essid(ssid + 2, ssid[1]);
777 	printf("\n");
778 }
779 
780 /*
781  * Return the bssid of a frame.
782  */
783 static const uint8_t *
784 ieee80211_getbssid(const struct ieee80211vap *vap,
785 	const struct ieee80211_frame *wh)
786 {
787 	if (vap->iv_opmode == IEEE80211_M_STA)
788 		return wh->i_addr2;
789 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) != IEEE80211_FC1_DIR_NODS)
790 		return wh->i_addr1;
791 	if ((wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) == IEEE80211_FC0_SUBTYPE_PS_POLL)
792 		return wh->i_addr1;
793 	return wh->i_addr3;
794 }
795 
796 #include <machine/stdarg.h>
797 
798 void
799 ieee80211_note(const struct ieee80211vap *vap, const char *fmt, ...)
800 {
801 	char buf[128];		/* XXX */
802 	va_list ap;
803 
804 	va_start(ap, fmt);
805 	vsnprintf(buf, sizeof(buf), fmt, ap);
806 	va_end(ap);
807 
808 	if_printf(vap->iv_ifp, "%s", buf);	/* NB: no \n */
809 }
810 
811 void
812 ieee80211_note_frame(const struct ieee80211vap *vap,
813 	const struct ieee80211_frame *wh,
814 	const char *fmt, ...)
815 {
816 	char buf[128];		/* XXX */
817 	va_list ap;
818 
819 	va_start(ap, fmt);
820 	vsnprintf(buf, sizeof(buf), fmt, ap);
821 	va_end(ap);
822 	if_printf(vap->iv_ifp, "[%s] %s\n",
823 		ether_sprintf(ieee80211_getbssid(vap, wh)), buf);
824 }
825 
826 void
827 ieee80211_note_mac(const struct ieee80211vap *vap,
828 	const uint8_t mac[IEEE80211_ADDR_LEN],
829 	const char *fmt, ...)
830 {
831 	char buf[128];		/* XXX */
832 	va_list ap;
833 
834 	va_start(ap, fmt);
835 	vsnprintf(buf, sizeof(buf), fmt, ap);
836 	va_end(ap);
837 	if_printf(vap->iv_ifp, "[%s] %s\n", ether_sprintf(mac), buf);
838 }
839 
840 void
841 ieee80211_discard_frame(const struct ieee80211vap *vap,
842 	const struct ieee80211_frame *wh,
843 	const char *type, const char *fmt, ...)
844 {
845 	va_list ap;
846 
847 	if_printf(vap->iv_ifp, "[%s] discard ",
848 		ether_sprintf(ieee80211_getbssid(vap, wh)));
849 	if (type == NULL) {
850 		printf("%s frame, ", ieee80211_mgt_subtype_name[
851 			(wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK) >>
852 			IEEE80211_FC0_SUBTYPE_SHIFT]);
853 	} else
854 		printf("%s frame, ", type);
855 	va_start(ap, fmt);
856 	vprintf(fmt, ap);
857 	va_end(ap);
858 	printf("\n");
859 }
860 
861 void
862 ieee80211_discard_ie(const struct ieee80211vap *vap,
863 	const struct ieee80211_frame *wh,
864 	const char *type, const char *fmt, ...)
865 {
866 	va_list ap;
867 
868 	if_printf(vap->iv_ifp, "[%s] discard ",
869 		ether_sprintf(ieee80211_getbssid(vap, wh)));
870 	if (type != NULL)
871 		printf("%s information element, ", type);
872 	else
873 		printf("information element, ");
874 	va_start(ap, fmt);
875 	vprintf(fmt, ap);
876 	va_end(ap);
877 	printf("\n");
878 }
879 
880 void
881 ieee80211_discard_mac(const struct ieee80211vap *vap,
882 	const uint8_t mac[IEEE80211_ADDR_LEN],
883 	const char *type, const char *fmt, ...)
884 {
885 	va_list ap;
886 
887 	if_printf(vap->iv_ifp, "[%s] discard ", ether_sprintf(mac));
888 	if (type != NULL)
889 		printf("%s frame, ", type);
890 	else
891 		printf("frame, ");
892 	va_start(ap, fmt);
893 	vprintf(fmt, ap);
894 	va_end(ap);
895 	printf("\n");
896 }
897 #endif /* IEEE80211_DEBUG */
898