xref: /freebsd/sys/net80211/ieee80211_adhoc.c (revision d91f8db5f1822c43cd256f19aae1d059e4b25a26)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2007-2009 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 #ifdef __FreeBSD__
30 __FBSDID("$FreeBSD$");
31 #endif
32 
33 /*
34  * IEEE 802.11 IBSS mode support.
35  */
36 #include "opt_inet.h"
37 #include "opt_wlan.h"
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/mbuf.h>
42 #include <sys/malloc.h>
43 #include <sys/kernel.h>
44 
45 #include <sys/socket.h>
46 #include <sys/sockio.h>
47 #include <sys/endian.h>
48 #include <sys/errno.h>
49 #include <sys/proc.h>
50 #include <sys/sysctl.h>
51 
52 #include <net/if.h>
53 #include <net/if_var.h>
54 #include <net/if_media.h>
55 #include <net/if_llc.h>
56 #include <net/if_private.h>
57 #include <net/ethernet.h>
58 
59 #include <net/bpf.h>
60 
61 #include <net80211/ieee80211_var.h>
62 #include <net80211/ieee80211_adhoc.h>
63 #include <net80211/ieee80211_input.h>
64 #ifdef IEEE80211_SUPPORT_SUPERG
65 #include <net80211/ieee80211_superg.h>
66 #endif
67 #ifdef IEEE80211_SUPPORT_TDMA
68 #include <net80211/ieee80211_tdma.h>
69 #endif
70 #include <net80211/ieee80211_sta.h>
71 
72 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
73 
74 static	void adhoc_vattach(struct ieee80211vap *);
75 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
76 static int adhoc_input(struct ieee80211_node *, struct mbuf *,
77 	    const struct ieee80211_rx_stats *, int, int);
78 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
79 	int subtype, const struct ieee80211_rx_stats *, int, int);
80 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
81 	    int subtype, const struct ieee80211_rx_stats *rxs, int, int);
82 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
83 
84 void
85 ieee80211_adhoc_attach(struct ieee80211com *ic)
86 {
87 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
88 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
89 }
90 
91 void
92 ieee80211_adhoc_detach(struct ieee80211com *ic)
93 {
94 }
95 
96 static void
97 adhoc_vdetach(struct ieee80211vap *vap)
98 {
99 }
100 
101 static void
102 adhoc_vattach(struct ieee80211vap *vap)
103 {
104 	vap->iv_newstate = adhoc_newstate;
105 	vap->iv_input = adhoc_input;
106 	if (vap->iv_opmode == IEEE80211_M_IBSS)
107 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
108 	else
109 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
110 	vap->iv_recv_ctl = adhoc_recv_ctl;
111 	vap->iv_opdetach = adhoc_vdetach;
112 #ifdef IEEE80211_SUPPORT_TDMA
113 	/*
114 	 * Throw control to tdma support.  Note we do this
115 	 * after setting up our callbacks so it can piggyback
116 	 * on top of us.
117 	 */
118 	if (vap->iv_caps & IEEE80211_C_TDMA)
119 		ieee80211_tdma_vattach(vap);
120 #endif
121 }
122 
123 static void
124 sta_leave(void *arg, struct ieee80211_node *ni)
125 {
126 	struct ieee80211vap *vap = ni->ni_vap;
127 
128 	if (ni != vap->iv_bss)
129 		ieee80211_node_leave(ni);
130 }
131 
132 /*
133  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
134  */
135 static int
136 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
137 {
138 	struct ieee80211com *ic = vap->iv_ic;
139 	struct ieee80211_node *ni;
140 	enum ieee80211_state ostate;
141 
142 	IEEE80211_LOCK_ASSERT(vap->iv_ic);
143 
144 	ostate = vap->iv_state;
145 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
146 	    __func__, ieee80211_state_name[ostate],
147 	    ieee80211_state_name[nstate], arg);
148 	vap->iv_state = nstate;			/* state transition */
149 	if (ostate != IEEE80211_S_SCAN)
150 		ieee80211_cancel_scan(vap);	/* background scan */
151 	ni = vap->iv_bss;			/* NB: no reference held */
152 	switch (nstate) {
153 	case IEEE80211_S_INIT:
154 		switch (ostate) {
155 		case IEEE80211_S_SCAN:
156 			ieee80211_cancel_scan(vap);
157 			break;
158 		default:
159 			break;
160 		}
161 		if (ostate != IEEE80211_S_INIT) {
162 			/* NB: optimize INIT -> INIT case */
163 			ieee80211_reset_bss(vap);
164 		}
165 		break;
166 	case IEEE80211_S_SCAN:
167 		switch (ostate) {
168 		case IEEE80211_S_RUN:		/* beacon miss */
169 			/* purge station table; entries are stale */
170 			ieee80211_iterate_nodes_vap(&ic->ic_sta, vap,
171 			    sta_leave, NULL);
172 			/* fall thru... */
173 		case IEEE80211_S_INIT:
174 			if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
175 			    !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
176 				/*
177 				 * Already have a channel; bypass the
178 				 * scan and startup immediately.
179 				 */
180 				ieee80211_create_ibss(vap,
181 				    ieee80211_ht_adjust_channel(ic,
182 				    vap->iv_des_chan, vap->iv_flags_ht));
183 				break;
184 			}
185 			/*
186 			 * Initiate a scan.  We can come here as a result
187 			 * of an IEEE80211_IOC_SCAN_REQ too in which case
188 			 * the vap will be marked with IEEE80211_FEXT_SCANREQ
189 			 * and the scan request parameters will be present
190 			 * in iv_scanreq.  Otherwise we do the default.
191 			 */
192 			if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
193 				ieee80211_check_scan(vap,
194 				    vap->iv_scanreq_flags,
195 				    vap->iv_scanreq_duration,
196 				    vap->iv_scanreq_mindwell,
197 				    vap->iv_scanreq_maxdwell,
198 				    vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
199 				vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
200 			} else
201 				ieee80211_check_scan_current(vap);
202 			break;
203 		case IEEE80211_S_SCAN:
204 			/*
205 			 * This can happen because of a change in state
206 			 * that requires a reset.  Trigger a new scan
207 			 * unless we're in manual roaming mode in which
208 			 * case an application must issue an explicit request.
209 			 */
210 			if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
211 				ieee80211_check_scan_current(vap);
212 			break;
213 		default:
214 			goto invalid;
215 		}
216 		break;
217 	case IEEE80211_S_RUN:
218 		if (vap->iv_flags & IEEE80211_F_WPA) {
219 			/* XXX validate prerequisites */
220 		}
221 		switch (ostate) {
222 		case IEEE80211_S_INIT:
223 			/*
224 			 * Already have a channel; bypass the
225 			 * scan and startup immediately.
226 			 * Note that ieee80211_create_ibss will call
227 			 * back to do a RUN->RUN state change.
228 			 */
229 			ieee80211_create_ibss(vap,
230 			    ieee80211_ht_adjust_channel(ic,
231 				ic->ic_curchan, vap->iv_flags_ht));
232 			/* NB: iv_bss is changed on return */
233 			ni = vap->iv_bss;
234 			break;
235 		case IEEE80211_S_SCAN:
236 #ifdef IEEE80211_DEBUG
237 			if (ieee80211_msg_debug(vap)) {
238 				ieee80211_note(vap,
239 				    "synchronized with %s ssid ",
240 				    ether_sprintf(ni->ni_bssid));
241 				ieee80211_print_essid(vap->iv_bss->ni_essid,
242 				    ni->ni_esslen);
243 				/* XXX MCS/HT */
244 				printf(" channel %d start %uMb\n",
245 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
246 				    IEEE80211_RATE2MBS(ni->ni_txrate));
247 			}
248 #endif
249 			break;
250 		case IEEE80211_S_RUN:	/* IBSS merge */
251 			break;
252 		default:
253 			goto invalid;
254 		}
255 		/*
256 		 * When 802.1x is not in use mark the port authorized
257 		 * at this point so traffic can flow.
258 		 */
259 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
260 			ieee80211_node_authorize(ni);
261 		/*
262 		 * Fake association when joining an existing bss.
263 		 */
264 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
265 		    ic->ic_newassoc != NULL)
266 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
267 		break;
268 	case IEEE80211_S_SLEEP:
269 		vap->iv_sta_ps(vap, 0);
270 		break;
271 	default:
272 	invalid:
273 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
274 		    "%s: unexpected state transition %s -> %s\n", __func__,
275 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
276 		break;
277 	}
278 	return 0;
279 }
280 
281 /*
282  * Decide if a received management frame should be
283  * printed when debugging is enabled.  This filters some
284  * of the less interesting frames that come frequently
285  * (e.g. beacons).
286  */
287 static __inline int
288 doprint(struct ieee80211vap *vap, int subtype)
289 {
290 	switch (subtype) {
291 	case IEEE80211_FC0_SUBTYPE_BEACON:
292 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
293 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
294 		return 1;
295 	}
296 	return 1;
297 }
298 
299 /*
300  * Process a received frame.  The node associated with the sender
301  * should be supplied.  If nothing was found in the node table then
302  * the caller is assumed to supply a reference to iv_bss instead.
303  * The RSSI and a timestamp are also supplied.  The RSSI data is used
304  * during AP scanning to select a AP to associate with; it can have
305  * any units so long as values have consistent units and higher values
306  * mean ``better signal''.  The receive timestamp is currently not used
307  * by the 802.11 layer.
308  */
309 static int
310 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
311     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
312 {
313 	struct ieee80211vap *vap = ni->ni_vap;
314 	struct ieee80211com *ic = ni->ni_ic;
315 	struct ifnet *ifp = vap->iv_ifp;
316 	struct ieee80211_frame *wh;
317 	struct ieee80211_key *key;
318 	struct ether_header *eh;
319 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
320 	uint8_t dir, type, subtype, qos;
321 	uint8_t *bssid;
322 	int is_hw_decrypted = 0;
323 	int has_decrypted = 0;
324 
325 	/*
326 	 * Some devices do hardware decryption all the way through
327 	 * to pretending the frame wasn't encrypted in the first place.
328 	 * So, tag it appropriately so it isn't discarded inappropriately.
329 	 */
330 	if ((rxs != NULL) && (rxs->c_pktflags & IEEE80211_RX_F_DECRYPTED))
331 		is_hw_decrypted = 1;
332 
333 	if (m->m_flags & M_AMPDU_MPDU) {
334 		/*
335 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
336 		 * w/ M_AMPDU_MPDU marked have already passed through
337 		 * here but were received out of order and been held on
338 		 * the reorder queue.  When resubmitted they are marked
339 		 * with the M_AMPDU_MPDU flag and we can bypass most of
340 		 * the normal processing.
341 		 */
342 		wh = mtod(m, struct ieee80211_frame *);
343 		type = IEEE80211_FC0_TYPE_DATA;
344 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
345 		subtype = IEEE80211_FC0_SUBTYPE_QOS_DATA;
346 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
347 		goto resubmit_ampdu;
348 	}
349 
350 	KASSERT(ni != NULL, ("null node"));
351 	ni->ni_inact = ni->ni_inact_reload;
352 
353 	type = -1;			/* undefined */
354 
355 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
356 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
357 		    ni->ni_macaddr, NULL,
358 		    "too short (1): len %u", m->m_pkthdr.len);
359 		vap->iv_stats.is_rx_tooshort++;
360 		goto out;
361 	}
362 	/*
363 	 * Bit of a cheat here, we use a pointer for a 3-address
364 	 * frame format but don't reference fields past outside
365 	 * ieee80211_frame_min w/o first validating the data is
366 	 * present.
367 	 */
368 	wh = mtod(m, struct ieee80211_frame *);
369 
370 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
371 	    IEEE80211_FC0_VERSION_0) {
372 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
373 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
374 		    wh->i_fc[0], wh->i_fc[1]);
375 		vap->iv_stats.is_rx_badversion++;
376 		goto err;
377 	}
378 
379 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
380 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
381 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
382 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
383 		if (dir != IEEE80211_FC1_DIR_NODS)
384 			bssid = wh->i_addr1;
385 		else if (type == IEEE80211_FC0_TYPE_CTL)
386 			bssid = wh->i_addr1;
387 		else {
388 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
389 				IEEE80211_DISCARD_MAC(vap,
390 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
391 				    NULL, "too short (2): len %u",
392 				    m->m_pkthdr.len);
393 				vap->iv_stats.is_rx_tooshort++;
394 				goto out;
395 			}
396 			bssid = wh->i_addr3;
397 		}
398 		/*
399 		 * Validate the bssid.
400 		 */
401 		if (!(type == IEEE80211_FC0_TYPE_MGT &&
402 		     (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
403 		      subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) &&
404 		    !IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
405 		    !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
406 			/* not interested in */
407 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
408 			    bssid, NULL, "%s", "not to bss");
409 			vap->iv_stats.is_rx_wrongbss++;
410 			goto out;
411 		}
412 		/*
413 		 * Data frame, cons up a node when it doesn't
414 		 * exist. This should probably done after an ACL check.
415 		 */
416 		if (type == IEEE80211_FC0_TYPE_DATA &&
417 		    ni == vap->iv_bss &&
418 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
419 			/*
420 			 * Beware of frames that come in too early; we
421 			 * can receive broadcast frames and creating sta
422 			 * entries will blow up because there is no bss
423 			 * channel yet.
424 			 */
425 			if (vap->iv_state != IEEE80211_S_RUN) {
426 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
427 				    wh, "data", "not in RUN state (%s)",
428 				    ieee80211_state_name[vap->iv_state]);
429 				vap->iv_stats.is_rx_badstate++;
430 				goto err;
431 			}
432 			/*
433 			 * Fake up a node for this newly discovered member
434 			 * of the IBSS.
435 			 *
436 			 * Note: This doesn't "upgrade" the node to 11n;
437 			 * that will happen after a probe request/response
438 			 * exchange.
439 			 */
440 			ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
441 			if (ni == NULL) {
442 				/* NB: stat kept for alloc failure */
443 				goto err;
444 			}
445 		}
446 		IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
447 		ni->ni_noise = nf;
448 		if (IEEE80211_HAS_SEQ(type, subtype) &&
449 		    IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
450 			uint8_t tid = ieee80211_gettid(wh);
451 			if (IEEE80211_QOS_HAS_SEQ(wh) &&
452 			    TID_TO_WME_AC(tid) >= WME_AC_VI)
453 				ic->ic_wme.wme_hipri_traffic++;
454 			if (! ieee80211_check_rxseq(ni, wh, bssid, rxs))
455 				goto out;
456 		}
457 	}
458 
459 	switch (type) {
460 	case IEEE80211_FC0_TYPE_DATA:
461 		hdrspace = ieee80211_hdrspace(ic, wh);
462 		if (m->m_len < hdrspace &&
463 		    (m = m_pullup(m, hdrspace)) == NULL) {
464 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
465 			    ni->ni_macaddr, NULL,
466 			    "data too short: expecting %u", hdrspace);
467 			vap->iv_stats.is_rx_tooshort++;
468 			goto out;		/* XXX */
469 		}
470 		if (dir != IEEE80211_FC1_DIR_NODS) {
471 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
472 			    wh, "data", "incorrect dir 0x%x", dir);
473 			vap->iv_stats.is_rx_wrongdir++;
474 			goto out;
475 		}
476 		/* XXX no power-save support */
477 
478 		/*
479 		 * Handle A-MPDU re-ordering.  If the frame is to be
480 		 * processed directly then ieee80211_ampdu_reorder
481 		 * will return 0; otherwise it has consumed the mbuf
482 		 * and we should do nothing more with it.
483 		 */
484 		if ((m->m_flags & M_AMPDU) &&
485 		    ieee80211_ampdu_reorder(ni, m, rxs) != 0) {
486 			m = NULL;
487 			goto out;
488 		}
489 	resubmit_ampdu:
490 
491 		/*
492 		 * Handle privacy requirements.  Note that we
493 		 * must not be preempted from here until after
494 		 * we (potentially) call ieee80211_crypto_demic;
495 		 * otherwise we may violate assumptions in the
496 		 * crypto cipher modules used to do delayed update
497 		 * of replay sequence numbers.
498 		 */
499 		if (is_hw_decrypted || IEEE80211_IS_PROTECTED(wh)) {
500 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
501 				/*
502 				 * Discard encrypted frames when privacy is off.
503 				 */
504 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
505 				    wh, "WEP", "%s", "PRIVACY off");
506 				vap->iv_stats.is_rx_noprivacy++;
507 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
508 				goto out;
509 			}
510 			if (ieee80211_crypto_decap(ni, m, hdrspace, &key) == 0) {
511 				/* NB: stats+msgs handled in crypto_decap */
512 				IEEE80211_NODE_STAT(ni, rx_wepfail);
513 				goto out;
514 			}
515 			wh = mtod(m, struct ieee80211_frame *);
516 			wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
517 			has_decrypted = 1;
518 		} else {
519 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
520 			key = NULL;
521 		}
522 
523 		/*
524 		 * Save QoS bits for use below--before we strip the header.
525 		 */
526 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS_DATA)
527 			qos = ieee80211_getqos(wh)[0];
528 		else
529 			qos = 0;
530 
531 		/*
532 		 * Next up, any fragmentation.
533 		 */
534 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
535 			m = ieee80211_defrag(ni, m, hdrspace, has_decrypted);
536 			if (m == NULL) {
537 				/* Fragment dropped or frame not complete yet */
538 				goto out;
539 			}
540 		}
541 		wh = NULL;		/* no longer valid, catch any uses */
542 
543 		/*
544 		 * Next strip any MSDU crypto bits.
545 		 */
546 		if (!ieee80211_crypto_demic(vap, key, m, 0)) {
547 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
548 			    ni->ni_macaddr, "data", "%s", "demic error");
549 			vap->iv_stats.is_rx_demicfail++;
550 			IEEE80211_NODE_STAT(ni, rx_demicfail);
551 			goto out;
552 		}
553 
554 		/* copy to listener after decrypt */
555 		if (ieee80211_radiotap_active_vap(vap))
556 			ieee80211_radiotap_rx(vap, m);
557 		need_tap = 0;
558 
559 		/*
560 		 * Finally, strip the 802.11 header.
561 		 */
562 		m = ieee80211_decap(vap, m, hdrspace, qos);
563 		if (m == NULL) {
564 			/* XXX mask bit to check for both */
565 			/* don't count Null data frames as errors */
566 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
567 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
568 				goto out;
569 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
570 			    ni->ni_macaddr, "data", "%s", "decap error");
571 			vap->iv_stats.is_rx_decap++;
572 			IEEE80211_NODE_STAT(ni, rx_decap);
573 			goto err;
574 		}
575 		if (!(qos & IEEE80211_QOS_AMSDU))
576 			eh = mtod(m, struct ether_header *);
577 		else
578 			eh = NULL;
579 		if (!ieee80211_node_is_authorized(ni)) {
580 			/*
581 			 * Deny any non-PAE frames received prior to
582 			 * authorization.  For open/shared-key
583 			 * authentication the port is mark authorized
584 			 * after authentication completes.  For 802.1x
585 			 * the port is not marked authorized by the
586 			 * authenticator until the handshake has completed.
587 			 */
588 			if (eh == NULL ||
589 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
590 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
591 				    ni->ni_macaddr, "data", "unauthorized or "
592 				    "unknown port: ether type 0x%x len %u",
593 				    eh == NULL ? -1 : eh->ether_type,
594 				    m->m_pkthdr.len);
595 				vap->iv_stats.is_rx_unauth++;
596 				IEEE80211_NODE_STAT(ni, rx_unauth);
597 				goto err;
598 			}
599 		} else {
600 			/*
601 			 * When denying unencrypted frames, discard
602 			 * any non-PAE frames received without encryption.
603 			 */
604 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
605 			    ((has_decrypted == 0) && (m->m_flags & M_WEP) == 0) &&
606 			    (is_hw_decrypted == 0) &&
607 			    (eh == NULL ||
608 			     eh->ether_type != htons(ETHERTYPE_PAE))) {
609 				/*
610 				 * Drop unencrypted frames.
611 				 */
612 				vap->iv_stats.is_rx_unencrypted++;
613 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
614 				goto out;
615 			}
616 		}
617 		/* XXX require HT? */
618 		if (qos & IEEE80211_QOS_AMSDU) {
619 			m = ieee80211_decap_amsdu(ni, m);
620 			if (m == NULL)
621 				return IEEE80211_FC0_TYPE_DATA;
622 		} else {
623 #ifdef IEEE80211_SUPPORT_SUPERG
624 			m = ieee80211_decap_fastframe(vap, ni, m);
625 			if (m == NULL)
626 				return IEEE80211_FC0_TYPE_DATA;
627 #endif
628 		}
629 		if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
630 			ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
631 		else
632 			ieee80211_deliver_data(vap, ni, m);
633 		return IEEE80211_FC0_TYPE_DATA;
634 
635 	case IEEE80211_FC0_TYPE_MGT:
636 		vap->iv_stats.is_rx_mgmt++;
637 		IEEE80211_NODE_STAT(ni, rx_mgmt);
638 		if (dir != IEEE80211_FC1_DIR_NODS) {
639 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
640 			    wh, "data", "incorrect dir 0x%x", dir);
641 			vap->iv_stats.is_rx_wrongdir++;
642 			goto err;
643 		}
644 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
645 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
646 			    ni->ni_macaddr, "mgt", "too short: len %u",
647 			    m->m_pkthdr.len);
648 			vap->iv_stats.is_rx_tooshort++;
649 			goto out;
650 		}
651 #ifdef IEEE80211_DEBUG
652 		if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
653 		    ieee80211_msg_dumppkts(vap)) {
654 			if_printf(ifp, "received %s from %s rssi %d\n",
655 			    ieee80211_mgt_subtype_name(subtype),
656 			    ether_sprintf(wh->i_addr2), rssi);
657 		}
658 #endif
659 		if (IEEE80211_IS_PROTECTED(wh)) {
660 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
661 			    wh, NULL, "%s", "WEP set but not permitted");
662 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
663 			goto out;
664 		}
665 		vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
666 		goto out;
667 
668 	case IEEE80211_FC0_TYPE_CTL:
669 		vap->iv_stats.is_rx_ctl++;
670 		IEEE80211_NODE_STAT(ni, rx_ctrl);
671 		vap->iv_recv_ctl(ni, m, subtype);
672 		goto out;
673 
674 	default:
675 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
676 		    wh, "bad", "frame type 0x%x", type);
677 		/* should not come here */
678 		break;
679 	}
680 err:
681 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
682 out:
683 	if (m != NULL) {
684 		if (need_tap && ieee80211_radiotap_active_vap(vap))
685 			ieee80211_radiotap_rx(vap, m);
686 		m_freem(m);
687 	}
688 	return type;
689 }
690 
691 static int
692 is11bclient(const uint8_t *rates, const uint8_t *xrates)
693 {
694 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
695 	int i;
696 
697 	/* NB: the 11b clients we care about will not have xrates */
698 	if (xrates != NULL || rates == NULL)
699 		return 0;
700 	for (i = 0; i < rates[1]; i++) {
701 		int r = rates[2+i] & IEEE80211_RATE_VAL;
702 		if (r > 2*11 || ((1<<r) & brates) == 0)
703 			return 0;
704 	}
705 	return 1;
706 }
707 
708 static void
709 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
710 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
711 {
712 	struct ieee80211vap *vap = ni->ni_vap;
713 	struct ieee80211com *ic = ni->ni_ic;
714 	struct ieee80211_channel *rxchan = ic->ic_curchan;
715 	struct ieee80211_frame *wh;
716 	uint8_t *frm, *efrm;
717 	uint8_t *ssid, *rates, *xrates;
718 #if 0
719 	int ht_state_change = 0;
720 #endif
721 
722 	wh = mtod(m0, struct ieee80211_frame *);
723 	frm = (uint8_t *)&wh[1];
724 	efrm = mtod(m0, uint8_t *) + m0->m_len;
725 
726 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
727 	    "%s: recv mgmt frame, addr2=%6D, ni=%p (%6D) fc=%.02x %.02x\n",
728 	    __func__,
729 	    wh->i_addr2, ":",
730 	    ni,
731 	    ni->ni_macaddr, ":",
732 	    wh->i_fc[0],
733 	    wh->i_fc[1]);
734 	switch (subtype) {
735 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
736 	case IEEE80211_FC0_SUBTYPE_BEACON: {
737 		struct ieee80211_scanparams scan;
738 		struct ieee80211_channel *c;
739 		/*
740 		 * We process beacon/probe response
741 		 * frames to discover neighbors.
742 		 */
743 		if (rxs != NULL) {
744 			c = ieee80211_lookup_channel_rxstatus(vap, rxs);
745 			if (c != NULL)
746 				rxchan = c;
747 		}
748 		if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
749 			return;
750 		/*
751 		 * Count frame now that we know it's to be processed.
752 		 */
753 		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
754 			vap->iv_stats.is_rx_beacon++;		/* XXX remove */
755 			IEEE80211_NODE_STAT(ni, rx_beacons);
756 		} else
757 			IEEE80211_NODE_STAT(ni, rx_proberesp);
758 		/*
759 		 * If scanning, just pass information to the scan module.
760 		 */
761 		if (ic->ic_flags & IEEE80211_F_SCAN) {
762 			if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
763 				/*
764 				 * Actively scanning a channel marked passive;
765 				 * send a probe request now that we know there
766 				 * is 802.11 traffic present.
767 				 *
768 				 * XXX check if the beacon we recv'd gives
769 				 * us what we need and suppress the probe req
770 				 */
771 				ieee80211_probe_curchan(vap, 1);
772 				ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
773 			}
774 			ieee80211_add_scan(vap, rxchan, &scan, wh,
775 			    subtype, rssi, nf);
776 			return;
777 		}
778 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
779 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
780 				/*
781 				 * Create a new entry in the neighbor table.
782 				 *
783 				 * XXX TODO:
784 				 *
785 				 * Here we're not scanning; so if we have an
786 				 * SSID then make sure it matches our SSID.
787 				 * Otherwise this code will match on all IBSS
788 				 * beacons/probe requests for all SSIDs,
789 				 * filling the node table with nodes that
790 				 * aren't ours.
791 				 */
792 				if (ieee80211_ibss_node_check_new(ni, &scan)) {
793 					ni = ieee80211_add_neighbor(vap, wh, &scan);
794 					/*
795 					 * Send a probe request so we announce 11n
796 					 * capabilities.
797 					 */
798 					ieee80211_send_probereq(ni, /* node */
799 					    vap->iv_myaddr, /* SA */
800 					    ni->ni_macaddr, /* DA */
801 					    vap->iv_bss->ni_bssid, /* BSSID */
802 					    vap->iv_bss->ni_essid,
803 					    vap->iv_bss->ni_esslen); /* SSID */
804 				} else
805 					ni = NULL;
806 
807 				/*
808 				 * Send a probe request so we announce 11n
809 				 * capabilities.
810 				 *
811 				 * Don't do this if we're scanning.
812 				 */
813 				if (! (ic->ic_flags & IEEE80211_F_SCAN))
814 					ieee80211_send_probereq(ni, /* node */
815 						vap->iv_myaddr, /* SA */
816 						ni->ni_macaddr, /* DA */
817 						vap->iv_bss->ni_bssid, /* BSSID */
818 						vap->iv_bss->ni_essid,
819 						vap->iv_bss->ni_esslen); /* SSID */
820 
821 			} else if (ni->ni_capinfo == 0) {
822 				/*
823 				 * Update faked node created on transmit.
824 				 * Note this also updates the tsf.
825 				 */
826 				ieee80211_init_neighbor(ni, wh, &scan);
827 
828 				/*
829 				 * Send a probe request so we announce 11n
830 				 * capabilities.
831 				 */
832 				ieee80211_send_probereq(ni, /* node */
833 					vap->iv_myaddr, /* SA */
834 					ni->ni_macaddr, /* DA */
835 					vap->iv_bss->ni_bssid, /* BSSID */
836 					vap->iv_bss->ni_essid,
837 					vap->iv_bss->ni_esslen); /* SSID */
838 			} else {
839 				/*
840 				 * Record tsf for potential resync.
841 				 */
842 				memcpy(ni->ni_tstamp.data, scan.tstamp,
843 					sizeof(ni->ni_tstamp));
844 			}
845 			/*
846 			 * This isn't enabled yet - otherwise it would
847 			 * update the HT parameters and channel width
848 			 * from any node, which could lead to lots of
849 			 * strange behaviour if the 11n nodes aren't
850 			 * exactly configured to match.
851 			 */
852 #if 0
853 			if (scan.htcap != NULL && scan.htinfo != NULL &&
854 			    (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
855 				ieee80211_ht_updateparams(ni,
856 				    scan.htcap, scan.htinfo));
857 				if (ieee80211_ht_updateparams_final(ni,
858 				    scan.htcap, scan.htinfo))
859 					ht_state_change = 1;
860 			}
861 
862 			/* XXX same for VHT? */
863 #endif
864 			if (ni != NULL) {
865 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
866 				ni->ni_noise = nf;
867 			}
868 			/*
869 			 * Same here - the channel width change should
870 			 * be applied to the specific peer node, not
871 			 * to the ic.  Ie, the interface configuration
872 			 * should stay in its current channel width;
873 			 * but it should change the rate control and
874 			 * any queued frames for the given node only.
875 			 *
876 			 * Since there's no (current) way to inform
877 			 * the driver that a channel width change has
878 			 * occurred for a single node, just stub this
879 			 * out.
880 			 */
881 #if 0
882 			if (ht_state_change)
883 				ieee80211_update_chw(ic);
884 #endif
885 		}
886 		break;
887 	}
888 
889 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
890 		if (vap->iv_state != IEEE80211_S_RUN) {
891 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
892 			    wh, NULL, "wrong state %s",
893 			    ieee80211_state_name[vap->iv_state]);
894 			vap->iv_stats.is_rx_mgtdiscard++;
895 			return;
896 		}
897 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
898 			/* frame must be directed */
899 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
900 			    wh, NULL, "%s", "not unicast");
901 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
902 			return;
903 		}
904 
905 		/*
906 		 * prreq frame format
907 		 *	[tlv] ssid
908 		 *	[tlv] supported rates
909 		 *	[tlv] extended supported rates
910 		 */
911 		ssid = rates = xrates = NULL;
912 		while (efrm - frm > 1) {
913 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
914 			switch (*frm) {
915 			case IEEE80211_ELEMID_SSID:
916 				ssid = frm;
917 				break;
918 			case IEEE80211_ELEMID_RATES:
919 				rates = frm;
920 				break;
921 			case IEEE80211_ELEMID_XRATES:
922 				xrates = frm;
923 				break;
924 			}
925 			frm += frm[1] + 2;
926 		}
927 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
928 		if (xrates != NULL)
929 			IEEE80211_VERIFY_ELEMENT(xrates,
930 				IEEE80211_RATE_MAXSIZE - rates[1], return);
931 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
932 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
933 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
934 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
935 			    wh, NULL,
936 			    "%s", "no ssid with ssid suppression enabled");
937 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
938 			return;
939 		}
940 
941 		/* XXX find a better class or define it's own */
942 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
943 		    "%s", "recv probe req");
944 		/*
945 		 * Some legacy 11b clients cannot hack a complete
946 		 * probe response frame.  When the request includes
947 		 * only a bare-bones rate set, communicate this to
948 		 * the transmit side.
949 		 */
950 		ieee80211_send_proberesp(vap, wh->i_addr2,
951 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
952 
953 		/*
954 		 * Note: we don't benefit from stashing the probe request
955 		 * IEs away to use for IBSS negotiation, because we
956 		 * typically don't get all of the IEs.
957 		 */
958 		break;
959 
960 	case IEEE80211_FC0_SUBTYPE_ACTION:
961 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
962 		if ((ni == vap->iv_bss) &&
963 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
964 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
965 			    wh, NULL, "%s", "unknown node");
966 			vap->iv_stats.is_rx_mgtdiscard++;
967 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
968 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
969 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
970 			    wh, NULL, "%s", "not for us");
971 			vap->iv_stats.is_rx_mgtdiscard++;
972 		} else if (vap->iv_state != IEEE80211_S_RUN) {
973 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
974 			    wh, NULL, "wrong state %s",
975 			    ieee80211_state_name[vap->iv_state]);
976 			vap->iv_stats.is_rx_mgtdiscard++;
977 		} else {
978 			if (ieee80211_parse_action(ni, m0) == 0)
979 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
980 		}
981 		break;
982 
983 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
984 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
985 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
986 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
987 	case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
988 	case IEEE80211_FC0_SUBTYPE_ATIM:
989 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
990 	case IEEE80211_FC0_SUBTYPE_AUTH:
991 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
992 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
993 		    wh, NULL, "%s", "not handled");
994 		vap->iv_stats.is_rx_mgtdiscard++;
995 		break;
996 
997 	default:
998 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
999 		    wh, "mgt", "subtype 0x%x not handled", subtype);
1000 		vap->iv_stats.is_rx_badsubtype++;
1001 		break;
1002 	}
1003 }
1004 #undef IEEE80211_VERIFY_LENGTH
1005 #undef IEEE80211_VERIFY_ELEMENT
1006 
1007 static void
1008 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
1009 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
1010 {
1011 	struct ieee80211vap *vap = ni->ni_vap;
1012 	struct ieee80211com *ic = ni->ni_ic;
1013 
1014 	/*
1015 	 * Process management frames when scanning; useful for doing
1016 	 * a site-survey.
1017 	 */
1018 	if (ic->ic_flags & IEEE80211_F_SCAN)
1019 		adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
1020 	else {
1021 #ifdef IEEE80211_DEBUG
1022 		struct ieee80211_frame *wh;
1023 
1024 		wh = mtod(m0, struct ieee80211_frame *);
1025 #endif
1026 		switch (subtype) {
1027 		case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1028 		case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1029 		case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1030 		case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1031 		case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
1032 		case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1033 		case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
1034 		case IEEE80211_FC0_SUBTYPE_BEACON:
1035 		case IEEE80211_FC0_SUBTYPE_ATIM:
1036 		case IEEE80211_FC0_SUBTYPE_DISASSOC:
1037 		case IEEE80211_FC0_SUBTYPE_AUTH:
1038 		case IEEE80211_FC0_SUBTYPE_DEAUTH:
1039 		case IEEE80211_FC0_SUBTYPE_ACTION:
1040 		case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
1041 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
1042 			     wh, NULL, "%s", "not handled");
1043 			vap->iv_stats.is_rx_mgtdiscard++;
1044 			break;
1045 		default:
1046 			IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
1047 			     wh, "mgt", "subtype 0x%x not handled", subtype);
1048 			vap->iv_stats.is_rx_badsubtype++;
1049 			break;
1050 		}
1051 	}
1052 }
1053 
1054 static void
1055 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
1056 {
1057 
1058 	switch (subtype) {
1059 	case IEEE80211_FC0_SUBTYPE_BAR:
1060 		ieee80211_recv_bar(ni, m);
1061 		break;
1062 	}
1063 }
1064