xref: /freebsd/sys/net80211/ieee80211_adhoc.c (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*-
2  * Copyright (c) 2007-2009 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #ifdef __FreeBSD__
28 __FBSDID("$FreeBSD$");
29 #endif
30 
31 /*
32  * IEEE 802.11 IBSS mode support.
33  */
34 #include "opt_inet.h"
35 #include "opt_wlan.h"
36 
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/mbuf.h>
40 #include <sys/malloc.h>
41 #include <sys/kernel.h>
42 
43 #include <sys/socket.h>
44 #include <sys/sockio.h>
45 #include <sys/endian.h>
46 #include <sys/errno.h>
47 #include <sys/proc.h>
48 #include <sys/sysctl.h>
49 
50 #include <net/if.h>
51 #include <net/if_var.h>
52 #include <net/if_media.h>
53 #include <net/if_llc.h>
54 #include <net/ethernet.h>
55 
56 #include <net/bpf.h>
57 
58 #include <net80211/ieee80211_var.h>
59 #include <net80211/ieee80211_adhoc.h>
60 #include <net80211/ieee80211_input.h>
61 #ifdef IEEE80211_SUPPORT_SUPERG
62 #include <net80211/ieee80211_superg.h>
63 #endif
64 #ifdef IEEE80211_SUPPORT_TDMA
65 #include <net80211/ieee80211_tdma.h>
66 #endif
67 #include <net80211/ieee80211_sta.h>
68 
69 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
70 
71 static	void adhoc_vattach(struct ieee80211vap *);
72 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
73 static int adhoc_input(struct ieee80211_node *, struct mbuf *, int, int);
74 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
75 	int subtype, int, int);
76 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
77 	int subtype, int, int);
78 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
79 
80 void
81 ieee80211_adhoc_attach(struct ieee80211com *ic)
82 {
83 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
84 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
85 }
86 
87 void
88 ieee80211_adhoc_detach(struct ieee80211com *ic)
89 {
90 }
91 
92 static void
93 adhoc_vdetach(struct ieee80211vap *vap)
94 {
95 }
96 
97 static void
98 adhoc_vattach(struct ieee80211vap *vap)
99 {
100 	vap->iv_newstate = adhoc_newstate;
101 	vap->iv_input = adhoc_input;
102 	if (vap->iv_opmode == IEEE80211_M_IBSS)
103 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
104 	else
105 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
106 	vap->iv_recv_ctl = adhoc_recv_ctl;
107 	vap->iv_opdetach = adhoc_vdetach;
108 #ifdef IEEE80211_SUPPORT_TDMA
109 	/*
110 	 * Throw control to tdma support.  Note we do this
111 	 * after setting up our callbacks so it can piggyback
112 	 * on top of us.
113 	 */
114 	if (vap->iv_caps & IEEE80211_C_TDMA)
115 		ieee80211_tdma_vattach(vap);
116 #endif
117 }
118 
119 static void
120 sta_leave(void *arg, struct ieee80211_node *ni)
121 {
122 	struct ieee80211vap *vap = arg;
123 
124 	if (ni->ni_vap == vap && ni != vap->iv_bss)
125 		ieee80211_node_leave(ni);
126 }
127 
128 /*
129  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
130  */
131 static int
132 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
133 {
134 	struct ieee80211com *ic = vap->iv_ic;
135 	struct ieee80211_node *ni;
136 	enum ieee80211_state ostate;
137 
138 	IEEE80211_LOCK_ASSERT(vap->iv_ic);
139 
140 	ostate = vap->iv_state;
141 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
142 	    __func__, ieee80211_state_name[ostate],
143 	    ieee80211_state_name[nstate], arg);
144 	vap->iv_state = nstate;			/* state transition */
145 	if (ostate != IEEE80211_S_SCAN)
146 		ieee80211_cancel_scan(vap);	/* background scan */
147 	ni = vap->iv_bss;			/* NB: no reference held */
148 	switch (nstate) {
149 	case IEEE80211_S_INIT:
150 		switch (ostate) {
151 		case IEEE80211_S_SCAN:
152 			ieee80211_cancel_scan(vap);
153 			break;
154 		default:
155 			break;
156 		}
157 		if (ostate != IEEE80211_S_INIT) {
158 			/* NB: optimize INIT -> INIT case */
159 			ieee80211_reset_bss(vap);
160 		}
161 		break;
162 	case IEEE80211_S_SCAN:
163 		switch (ostate) {
164 		case IEEE80211_S_RUN:		/* beacon miss */
165 			/* purge station table; entries are stale */
166 			ieee80211_iterate_nodes(&ic->ic_sta, sta_leave, vap);
167 			/* fall thru... */
168 		case IEEE80211_S_INIT:
169 			if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
170 			    !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
171 				/*
172 				 * Already have a channel; bypass the
173 				 * scan and startup immediately.
174 				 */
175 				ieee80211_create_ibss(vap,
176 				    ieee80211_ht_adjust_channel(ic,
177 				    vap->iv_des_chan, vap->iv_flags_ht));
178 				break;
179 			}
180 			/*
181 			 * Initiate a scan.  We can come here as a result
182 			 * of an IEEE80211_IOC_SCAN_REQ too in which case
183 			 * the vap will be marked with IEEE80211_FEXT_SCANREQ
184 			 * and the scan request parameters will be present
185 			 * in iv_scanreq.  Otherwise we do the default.
186 			 */
187 			if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
188 				ieee80211_check_scan(vap,
189 				    vap->iv_scanreq_flags,
190 				    vap->iv_scanreq_duration,
191 				    vap->iv_scanreq_mindwell,
192 				    vap->iv_scanreq_maxdwell,
193 				    vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
194 				vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
195 			} else
196 				ieee80211_check_scan_current(vap);
197 			break;
198 		case IEEE80211_S_SCAN:
199 			/*
200 			 * This can happen because of a change in state
201 			 * that requires a reset.  Trigger a new scan
202 			 * unless we're in manual roaming mode in which
203 			 * case an application must issue an explicit request.
204 			 */
205 			if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
206 				ieee80211_check_scan_current(vap);
207 			break;
208 		default:
209 			goto invalid;
210 		}
211 		break;
212 	case IEEE80211_S_RUN:
213 		if (vap->iv_flags & IEEE80211_F_WPA) {
214 			/* XXX validate prerequisites */
215 		}
216 		switch (ostate) {
217 		case IEEE80211_S_SCAN:
218 #ifdef IEEE80211_DEBUG
219 			if (ieee80211_msg_debug(vap)) {
220 				ieee80211_note(vap,
221 				    "synchronized with %s ssid ",
222 				    ether_sprintf(ni->ni_bssid));
223 				ieee80211_print_essid(vap->iv_bss->ni_essid,
224 				    ni->ni_esslen);
225 				/* XXX MCS/HT */
226 				printf(" channel %d start %uMb\n",
227 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
228 				    IEEE80211_RATE2MBS(ni->ni_txrate));
229 			}
230 #endif
231 			break;
232 		default:
233 			goto invalid;
234 		}
235 		/*
236 		 * When 802.1x is not in use mark the port authorized
237 		 * at this point so traffic can flow.
238 		 */
239 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
240 			ieee80211_node_authorize(ni);
241 		/*
242 		 * Fake association when joining an existing bss.
243 		 */
244 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
245 		    ic->ic_newassoc != NULL)
246 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
247 		break;
248 	case IEEE80211_S_SLEEP:
249 		vap->iv_sta_ps(vap, 0);
250 		break;
251 	default:
252 	invalid:
253 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
254 		    "%s: unexpected state transition %s -> %s\n", __func__,
255 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
256 		break;
257 	}
258 	return 0;
259 }
260 
261 /*
262  * Decide if a received management frame should be
263  * printed when debugging is enabled.  This filters some
264  * of the less interesting frames that come frequently
265  * (e.g. beacons).
266  */
267 static __inline int
268 doprint(struct ieee80211vap *vap, int subtype)
269 {
270 	switch (subtype) {
271 	case IEEE80211_FC0_SUBTYPE_BEACON:
272 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
273 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
274 		return 1;
275 	}
276 	return 1;
277 }
278 
279 /*
280  * Process a received frame.  The node associated with the sender
281  * should be supplied.  If nothing was found in the node table then
282  * the caller is assumed to supply a reference to iv_bss instead.
283  * The RSSI and a timestamp are also supplied.  The RSSI data is used
284  * during AP scanning to select a AP to associate with; it can have
285  * any units so long as values have consistent units and higher values
286  * mean ``better signal''.  The receive timestamp is currently not used
287  * by the 802.11 layer.
288  */
289 static int
290 adhoc_input(struct ieee80211_node *ni, struct mbuf *m, int rssi, int nf)
291 {
292 #define	HAS_SEQ(type)	((type & 0x4) == 0)
293 	struct ieee80211vap *vap = ni->ni_vap;
294 	struct ieee80211com *ic = ni->ni_ic;
295 	struct ifnet *ifp = vap->iv_ifp;
296 	struct ieee80211_frame *wh;
297 	struct ieee80211_key *key;
298 	struct ether_header *eh;
299 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
300 	uint8_t dir, type, subtype, qos;
301 	uint8_t *bssid;
302 	uint16_t rxseq;
303 
304 	if (m->m_flags & M_AMPDU_MPDU) {
305 		/*
306 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
307 		 * w/ M_AMPDU_MPDU marked have already passed through
308 		 * here but were received out of order and been held on
309 		 * the reorder queue.  When resubmitted they are marked
310 		 * with the M_AMPDU_MPDU flag and we can bypass most of
311 		 * the normal processing.
312 		 */
313 		wh = mtod(m, struct ieee80211_frame *);
314 		type = IEEE80211_FC0_TYPE_DATA;
315 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
316 		subtype = IEEE80211_FC0_SUBTYPE_QOS;
317 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
318 		goto resubmit_ampdu;
319 	}
320 
321 	KASSERT(ni != NULL, ("null node"));
322 	ni->ni_inact = ni->ni_inact_reload;
323 
324 	type = -1;			/* undefined */
325 
326 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
327 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
328 		    ni->ni_macaddr, NULL,
329 		    "too short (1): len %u", m->m_pkthdr.len);
330 		vap->iv_stats.is_rx_tooshort++;
331 		goto out;
332 	}
333 	/*
334 	 * Bit of a cheat here, we use a pointer for a 3-address
335 	 * frame format but don't reference fields past outside
336 	 * ieee80211_frame_min w/o first validating the data is
337 	 * present.
338 	 */
339 	wh = mtod(m, struct ieee80211_frame *);
340 
341 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
342 	    IEEE80211_FC0_VERSION_0) {
343 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
344 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
345 		    wh->i_fc[0], wh->i_fc[1]);
346 		vap->iv_stats.is_rx_badversion++;
347 		goto err;
348 	}
349 
350 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
351 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
352 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
353 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
354 		if (dir != IEEE80211_FC1_DIR_NODS)
355 			bssid = wh->i_addr1;
356 		else if (type == IEEE80211_FC0_TYPE_CTL)
357 			bssid = wh->i_addr1;
358 		else {
359 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
360 				IEEE80211_DISCARD_MAC(vap,
361 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
362 				    NULL, "too short (2): len %u",
363 				    m->m_pkthdr.len);
364 				vap->iv_stats.is_rx_tooshort++;
365 				goto out;
366 			}
367 			bssid = wh->i_addr3;
368 		}
369 		/*
370 		 * Validate the bssid.
371 		 */
372 		if (!IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
373 		    !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
374 			/* not interested in */
375 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
376 			    bssid, NULL, "%s", "not to bss");
377 			vap->iv_stats.is_rx_wrongbss++;
378 			goto out;
379 		}
380 		/*
381 		 * Data frame, cons up a node when it doesn't
382 		 * exist. This should probably done after an ACL check.
383 		 */
384 		if (type == IEEE80211_FC0_TYPE_DATA &&
385 		    ni == vap->iv_bss &&
386 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
387 			/*
388 			 * Beware of frames that come in too early; we
389 			 * can receive broadcast frames and creating sta
390 			 * entries will blow up because there is no bss
391 			 * channel yet.
392 			 */
393 			if (vap->iv_state != IEEE80211_S_RUN) {
394 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
395 				    wh, "data", "not in RUN state (%s)",
396 				    ieee80211_state_name[vap->iv_state]);
397 				vap->iv_stats.is_rx_badstate++;
398 				goto err;
399 			}
400 			/*
401 			 * Fake up a node for this newly
402 			 * discovered member of the IBSS.
403 			 */
404 			ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
405 			if (ni == NULL) {
406 				/* NB: stat kept for alloc failure */
407 				goto err;
408 			}
409 		}
410 		IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
411 		ni->ni_noise = nf;
412 		if (HAS_SEQ(type)) {
413 			uint8_t tid = ieee80211_gettid(wh);
414 			if (IEEE80211_QOS_HAS_SEQ(wh) &&
415 			    TID_TO_WME_AC(tid) >= WME_AC_VI)
416 				ic->ic_wme.wme_hipri_traffic++;
417 			rxseq = le16toh(*(uint16_t *)wh->i_seq);
418 			if (! ieee80211_check_rxseq(ni, wh)) {
419 				/* duplicate, discard */
420 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
421 				    bssid, "duplicate",
422 				    "seqno <%u,%u> fragno <%u,%u> tid %u",
423 				    rxseq >> IEEE80211_SEQ_SEQ_SHIFT,
424 				    ni->ni_rxseqs[tid] >>
425 					IEEE80211_SEQ_SEQ_SHIFT,
426 				    rxseq & IEEE80211_SEQ_FRAG_MASK,
427 				    ni->ni_rxseqs[tid] &
428 					IEEE80211_SEQ_FRAG_MASK,
429 				    tid);
430 				vap->iv_stats.is_rx_dup++;
431 				IEEE80211_NODE_STAT(ni, rx_dup);
432 				goto out;
433 			}
434 			ni->ni_rxseqs[tid] = rxseq;
435 		}
436 	}
437 
438 	switch (type) {
439 	case IEEE80211_FC0_TYPE_DATA:
440 		hdrspace = ieee80211_hdrspace(ic, wh);
441 		if (m->m_len < hdrspace &&
442 		    (m = m_pullup(m, hdrspace)) == NULL) {
443 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
444 			    ni->ni_macaddr, NULL,
445 			    "data too short: expecting %u", hdrspace);
446 			vap->iv_stats.is_rx_tooshort++;
447 			goto out;		/* XXX */
448 		}
449 		if (dir != IEEE80211_FC1_DIR_NODS) {
450 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
451 			    wh, "data", "incorrect dir 0x%x", dir);
452 			vap->iv_stats.is_rx_wrongdir++;
453 			goto out;
454 		}
455 		/* XXX no power-save support */
456 
457 		/*
458 		 * Handle A-MPDU re-ordering.  If the frame is to be
459 		 * processed directly then ieee80211_ampdu_reorder
460 		 * will return 0; otherwise it has consumed the mbuf
461 		 * and we should do nothing more with it.
462 		 */
463 		if ((m->m_flags & M_AMPDU) &&
464 		    ieee80211_ampdu_reorder(ni, m) != 0) {
465 			m = NULL;
466 			goto out;
467 		}
468 	resubmit_ampdu:
469 
470 		/*
471 		 * Handle privacy requirements.  Note that we
472 		 * must not be preempted from here until after
473 		 * we (potentially) call ieee80211_crypto_demic;
474 		 * otherwise we may violate assumptions in the
475 		 * crypto cipher modules used to do delayed update
476 		 * of replay sequence numbers.
477 		 */
478 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
479 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
480 				/*
481 				 * Discard encrypted frames when privacy is off.
482 				 */
483 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
484 				    wh, "WEP", "%s", "PRIVACY off");
485 				vap->iv_stats.is_rx_noprivacy++;
486 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
487 				goto out;
488 			}
489 			key = ieee80211_crypto_decap(ni, m, hdrspace);
490 			if (key == NULL) {
491 				/* NB: stats+msgs handled in crypto_decap */
492 				IEEE80211_NODE_STAT(ni, rx_wepfail);
493 				goto out;
494 			}
495 			wh = mtod(m, struct ieee80211_frame *);
496 			wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
497 		} else {
498 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
499 			key = NULL;
500 		}
501 
502 		/*
503 		 * Save QoS bits for use below--before we strip the header.
504 		 */
505 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS) {
506 			qos = (dir == IEEE80211_FC1_DIR_DSTODS) ?
507 			    ((struct ieee80211_qosframe_addr4 *)wh)->i_qos[0] :
508 			    ((struct ieee80211_qosframe *)wh)->i_qos[0];
509 		} else
510 			qos = 0;
511 
512 		/*
513 		 * Next up, any fragmentation.
514 		 */
515 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
516 			m = ieee80211_defrag(ni, m, hdrspace);
517 			if (m == NULL) {
518 				/* Fragment dropped or frame not complete yet */
519 				goto out;
520 			}
521 		}
522 		wh = NULL;		/* no longer valid, catch any uses */
523 
524 		/*
525 		 * Next strip any MSDU crypto bits.
526 		 */
527 		if (key != NULL && !ieee80211_crypto_demic(vap, key, m, 0)) {
528 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
529 			    ni->ni_macaddr, "data", "%s", "demic error");
530 			vap->iv_stats.is_rx_demicfail++;
531 			IEEE80211_NODE_STAT(ni, rx_demicfail);
532 			goto out;
533 		}
534 
535 		/* copy to listener after decrypt */
536 		if (ieee80211_radiotap_active_vap(vap))
537 			ieee80211_radiotap_rx(vap, m);
538 		need_tap = 0;
539 
540 		/*
541 		 * Finally, strip the 802.11 header.
542 		 */
543 		m = ieee80211_decap(vap, m, hdrspace);
544 		if (m == NULL) {
545 			/* XXX mask bit to check for both */
546 			/* don't count Null data frames as errors */
547 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
548 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
549 				goto out;
550 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
551 			    ni->ni_macaddr, "data", "%s", "decap error");
552 			vap->iv_stats.is_rx_decap++;
553 			IEEE80211_NODE_STAT(ni, rx_decap);
554 			goto err;
555 		}
556 		eh = mtod(m, struct ether_header *);
557 		if (!ieee80211_node_is_authorized(ni)) {
558 			/*
559 			 * Deny any non-PAE frames received prior to
560 			 * authorization.  For open/shared-key
561 			 * authentication the port is mark authorized
562 			 * after authentication completes.  For 802.1x
563 			 * the port is not marked authorized by the
564 			 * authenticator until the handshake has completed.
565 			 */
566 			if (eh->ether_type != htons(ETHERTYPE_PAE)) {
567 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
568 				    eh->ether_shost, "data",
569 				    "unauthorized port: ether type 0x%x len %u",
570 				    eh->ether_type, m->m_pkthdr.len);
571 				vap->iv_stats.is_rx_unauth++;
572 				IEEE80211_NODE_STAT(ni, rx_unauth);
573 				goto err;
574 			}
575 		} else {
576 			/*
577 			 * When denying unencrypted frames, discard
578 			 * any non-PAE frames received without encryption.
579 			 */
580 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
581 			    (key == NULL && (m->m_flags & M_WEP) == 0) &&
582 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
583 				/*
584 				 * Drop unencrypted frames.
585 				 */
586 				vap->iv_stats.is_rx_unencrypted++;
587 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
588 				goto out;
589 			}
590 		}
591 		/* XXX require HT? */
592 		if (qos & IEEE80211_QOS_AMSDU) {
593 			m = ieee80211_decap_amsdu(ni, m);
594 			if (m == NULL)
595 				return IEEE80211_FC0_TYPE_DATA;
596 		} else {
597 #ifdef IEEE80211_SUPPORT_SUPERG
598 			m = ieee80211_decap_fastframe(vap, ni, m);
599 			if (m == NULL)
600 				return IEEE80211_FC0_TYPE_DATA;
601 #endif
602 		}
603 		if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
604 			ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
605 		else
606 			ieee80211_deliver_data(vap, ni, m);
607 		return IEEE80211_FC0_TYPE_DATA;
608 
609 	case IEEE80211_FC0_TYPE_MGT:
610 		vap->iv_stats.is_rx_mgmt++;
611 		IEEE80211_NODE_STAT(ni, rx_mgmt);
612 		if (dir != IEEE80211_FC1_DIR_NODS) {
613 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
614 			    wh, "data", "incorrect dir 0x%x", dir);
615 			vap->iv_stats.is_rx_wrongdir++;
616 			goto err;
617 		}
618 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
619 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
620 			    ni->ni_macaddr, "mgt", "too short: len %u",
621 			    m->m_pkthdr.len);
622 			vap->iv_stats.is_rx_tooshort++;
623 			goto out;
624 		}
625 #ifdef IEEE80211_DEBUG
626 		if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
627 		    ieee80211_msg_dumppkts(vap)) {
628 			if_printf(ifp, "received %s from %s rssi %d\n",
629 			    ieee80211_mgt_subtype_name[subtype >>
630 				IEEE80211_FC0_SUBTYPE_SHIFT],
631 			    ether_sprintf(wh->i_addr2), rssi);
632 		}
633 #endif
634 		if (wh->i_fc[1] & IEEE80211_FC1_PROTECTED) {
635 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
636 			    wh, NULL, "%s", "WEP set but not permitted");
637 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
638 			goto out;
639 		}
640 		vap->iv_recv_mgmt(ni, m, subtype, rssi, nf);
641 		goto out;
642 
643 	case IEEE80211_FC0_TYPE_CTL:
644 		vap->iv_stats.is_rx_ctl++;
645 		IEEE80211_NODE_STAT(ni, rx_ctrl);
646 		vap->iv_recv_ctl(ni, m, subtype);
647 		goto out;
648 
649 	default:
650 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
651 		    wh, "bad", "frame type 0x%x", type);
652 		/* should not come here */
653 		break;
654 	}
655 err:
656 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
657 out:
658 	if (m != NULL) {
659 		if (need_tap && ieee80211_radiotap_active_vap(vap))
660 			ieee80211_radiotap_rx(vap, m);
661 		m_freem(m);
662 	}
663 	return type;
664 }
665 
666 static int
667 is11bclient(const uint8_t *rates, const uint8_t *xrates)
668 {
669 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
670 	int i;
671 
672 	/* NB: the 11b clients we care about will not have xrates */
673 	if (xrates != NULL || rates == NULL)
674 		return 0;
675 	for (i = 0; i < rates[1]; i++) {
676 		int r = rates[2+i] & IEEE80211_RATE_VAL;
677 		if (r > 2*11 || ((1<<r) & brates) == 0)
678 			return 0;
679 	}
680 	return 1;
681 }
682 
683 static void
684 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
685 	int subtype, int rssi, int nf)
686 {
687 	struct ieee80211vap *vap = ni->ni_vap;
688 	struct ieee80211com *ic = ni->ni_ic;
689 	struct ieee80211_frame *wh;
690 	uint8_t *frm, *efrm, *sfrm;
691 	uint8_t *ssid, *rates, *xrates;
692 #if 0
693 	int ht_state_change = 0;
694 #endif
695 
696 	wh = mtod(m0, struct ieee80211_frame *);
697 	frm = (uint8_t *)&wh[1];
698 	efrm = mtod(m0, uint8_t *) + m0->m_len;
699 	switch (subtype) {
700 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
701 	case IEEE80211_FC0_SUBTYPE_BEACON: {
702 		struct ieee80211_scanparams scan;
703 		/*
704 		 * We process beacon/probe response
705 		 * frames to discover neighbors.
706 		 */
707 		if (ieee80211_parse_beacon(ni, m0, &scan) != 0)
708 			return;
709 		/*
710 		 * Count frame now that we know it's to be processed.
711 		 */
712 		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
713 			vap->iv_stats.is_rx_beacon++;		/* XXX remove */
714 			IEEE80211_NODE_STAT(ni, rx_beacons);
715 		} else
716 			IEEE80211_NODE_STAT(ni, rx_proberesp);
717 		/*
718 		 * If scanning, just pass information to the scan module.
719 		 */
720 		if (ic->ic_flags & IEEE80211_F_SCAN) {
721 			if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
722 				/*
723 				 * Actively scanning a channel marked passive;
724 				 * send a probe request now that we know there
725 				 * is 802.11 traffic present.
726 				 *
727 				 * XXX check if the beacon we recv'd gives
728 				 * us what we need and suppress the probe req
729 				 */
730 				ieee80211_probe_curchan(vap, 1);
731 				ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
732 			}
733 			ieee80211_add_scan(vap, &scan, wh, subtype, rssi, nf);
734 			return;
735 		}
736 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
737 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
738 				/*
739 				 * Create a new entry in the neighbor table.
740 				 */
741 				ni = ieee80211_add_neighbor(vap, wh, &scan);
742 			} else if (ni->ni_capinfo == 0) {
743 				/*
744 				 * Update faked node created on transmit.
745 				 * Note this also updates the tsf.
746 				 */
747 				ieee80211_init_neighbor(ni, wh, &scan);
748 			} else {
749 				/*
750 				 * Record tsf for potential resync.
751 				 */
752 				memcpy(ni->ni_tstamp.data, scan.tstamp,
753 					sizeof(ni->ni_tstamp));
754 			}
755 			/*
756 			 * This isn't enabled yet - otherwise it would
757 			 * update the HT parameters and channel width
758 			 * from any node, which could lead to lots of
759 			 * strange behaviour if the 11n nodes aren't
760 			 * exactly configured to match.
761 			 */
762 #if 0
763 			if (scan.htcap != NULL && scan.htinfo != NULL &&
764 			    (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
765 				if (ieee80211_ht_updateparams(ni,
766 				    scan.htcap, scan.htinfo))
767 					ht_state_change = 1;
768 			}
769 #endif
770 			if (ni != NULL) {
771 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
772 				ni->ni_noise = nf;
773 			}
774 			/*
775 			 * Same here - the channel width change should
776 			 * be applied to the specific peer node, not
777 			 * to the ic.  Ie, the interface configuration
778 			 * should stay in its current channel width;
779 			 * but it should change the rate control and
780 			 * any queued frames for the given node only.
781 			 *
782 			 * Since there's no (current) way to inform
783 			 * the driver that a channel width change has
784 			 * occured for a single node, just stub this
785 			 * out.
786 			 */
787 #if 0
788 			if (ht_state_change)
789 				ieee80211_update_chw(ic);
790 #endif
791 		}
792 		break;
793 	}
794 
795 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
796 		if (vap->iv_state != IEEE80211_S_RUN) {
797 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
798 			    wh, NULL, "wrong state %s",
799 			    ieee80211_state_name[vap->iv_state]);
800 			vap->iv_stats.is_rx_mgtdiscard++;
801 			return;
802 		}
803 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
804 			/* frame must be directed */
805 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
806 			    wh, NULL, "%s", "not unicast");
807 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
808 			return;
809 		}
810 
811 		/*
812 		 * prreq frame format
813 		 *	[tlv] ssid
814 		 *	[tlv] supported rates
815 		 *	[tlv] extended supported rates
816 		 */
817 		ssid = rates = xrates = NULL;
818 		sfrm = frm;
819 		while (efrm - frm > 1) {
820 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
821 			switch (*frm) {
822 			case IEEE80211_ELEMID_SSID:
823 				ssid = frm;
824 				break;
825 			case IEEE80211_ELEMID_RATES:
826 				rates = frm;
827 				break;
828 			case IEEE80211_ELEMID_XRATES:
829 				xrates = frm;
830 				break;
831 			}
832 			frm += frm[1] + 2;
833 		}
834 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
835 		if (xrates != NULL)
836 			IEEE80211_VERIFY_ELEMENT(xrates,
837 				IEEE80211_RATE_MAXSIZE - rates[1], return);
838 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
839 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
840 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
841 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
842 			    wh, NULL,
843 			    "%s", "no ssid with ssid suppression enabled");
844 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
845 			return;
846 		}
847 
848 		/* XXX find a better class or define it's own */
849 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
850 		    "%s", "recv probe req");
851 		/*
852 		 * Some legacy 11b clients cannot hack a complete
853 		 * probe response frame.  When the request includes
854 		 * only a bare-bones rate set, communicate this to
855 		 * the transmit side.
856 		 */
857 		ieee80211_send_proberesp(vap, wh->i_addr2,
858 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
859 		break;
860 
861 	case IEEE80211_FC0_SUBTYPE_ACTION:
862 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
863 		if (ni == vap->iv_bss) {
864 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
865 			    wh, NULL, "%s", "unknown node");
866 			vap->iv_stats.is_rx_mgtdiscard++;
867 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
868 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
869 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
870 			    wh, NULL, "%s", "not for us");
871 			vap->iv_stats.is_rx_mgtdiscard++;
872 		} else if (vap->iv_state != IEEE80211_S_RUN) {
873 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
874 			    wh, NULL, "wrong state %s",
875 			    ieee80211_state_name[vap->iv_state]);
876 			vap->iv_stats.is_rx_mgtdiscard++;
877 		} else {
878 			if (ieee80211_parse_action(ni, m0) == 0)
879 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
880 		}
881 		break;
882 
883 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
884 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
885 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
886 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
887 	case IEEE80211_FC0_SUBTYPE_ATIM:
888 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
889 	case IEEE80211_FC0_SUBTYPE_AUTH:
890 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
891 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
892 		    wh, NULL, "%s", "not handled");
893 		vap->iv_stats.is_rx_mgtdiscard++;
894 		break;
895 
896 	default:
897 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
898 		    wh, "mgt", "subtype 0x%x not handled", subtype);
899 		vap->iv_stats.is_rx_badsubtype++;
900 		break;
901 	}
902 }
903 #undef IEEE80211_VERIFY_LENGTH
904 #undef IEEE80211_VERIFY_ELEMENT
905 
906 static void
907 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
908 	int subtype, int rssi, int nf)
909 {
910 	struct ieee80211vap *vap = ni->ni_vap;
911 	struct ieee80211com *ic = ni->ni_ic;
912 	struct ieee80211_frame *wh;
913 
914 	/*
915 	 * Process management frames when scanning; useful for doing
916 	 * a site-survey.
917 	 */
918 	if (ic->ic_flags & IEEE80211_F_SCAN)
919 		adhoc_recv_mgmt(ni, m0, subtype, rssi, nf);
920 	else {
921 		wh = mtod(m0, struct ieee80211_frame *);
922 		switch (subtype) {
923 		case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
924 		case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
925 		case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
926 		case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
927 		case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
928 		case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
929 		case IEEE80211_FC0_SUBTYPE_BEACON:
930 		case IEEE80211_FC0_SUBTYPE_ATIM:
931 		case IEEE80211_FC0_SUBTYPE_DISASSOC:
932 		case IEEE80211_FC0_SUBTYPE_AUTH:
933 		case IEEE80211_FC0_SUBTYPE_DEAUTH:
934 		case IEEE80211_FC0_SUBTYPE_ACTION:
935 		case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
936 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
937 			     wh, NULL, "%s", "not handled");
938 			vap->iv_stats.is_rx_mgtdiscard++;
939 			break;
940 		default:
941 			IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
942 			     wh, "mgt", "subtype 0x%x not handled", subtype);
943 			vap->iv_stats.is_rx_badsubtype++;
944 			break;
945 		}
946 	}
947 }
948 
949 static void
950 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
951 {
952 
953 	switch (subtype) {
954 	case IEEE80211_FC0_SUBTYPE_BAR:
955 		ieee80211_recv_bar(ni, m);
956 		break;
957 	}
958 }
959