xref: /freebsd/sys/net80211/ieee80211_adhoc.c (revision a233c71650a1e5b29723a8547ea160e105aa855e)
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 /*
29  * IEEE 802.11 IBSS mode support.
30  */
31 #include "opt_inet.h"
32 #include "opt_wlan.h"
33 
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/mbuf.h>
37 #include <sys/malloc.h>
38 #include <sys/kernel.h>
39 
40 #include <sys/socket.h>
41 #include <sys/sockio.h>
42 #include <sys/endian.h>
43 #include <sys/errno.h>
44 #include <sys/proc.h>
45 #include <sys/sysctl.h>
46 
47 #include <net/if.h>
48 #include <net/if_var.h>
49 #include <net/if_media.h>
50 #include <net/if_llc.h>
51 #include <net/ethernet.h>
52 
53 #include <net/bpf.h>
54 
55 #include <net80211/ieee80211_var.h>
56 #include <net80211/ieee80211_adhoc.h>
57 #include <net80211/ieee80211_input.h>
58 #ifdef IEEE80211_SUPPORT_SUPERG
59 #include <net80211/ieee80211_superg.h>
60 #endif
61 #ifdef IEEE80211_SUPPORT_TDMA
62 #include <net80211/ieee80211_tdma.h>
63 #endif
64 #include <net80211/ieee80211_sta.h>
65 
66 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
67 
68 static	void adhoc_vattach(struct ieee80211vap *);
69 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
70 static int adhoc_input(struct ieee80211_node *, struct mbuf *,
71 	    const struct ieee80211_rx_stats *, int, int);
72 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
73 	int subtype, const struct ieee80211_rx_stats *, int, int);
74 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
75 	    int subtype, const struct ieee80211_rx_stats *rxs, int, int);
76 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
77 
78 void
ieee80211_adhoc_attach(struct ieee80211com * ic)79 ieee80211_adhoc_attach(struct ieee80211com *ic)
80 {
81 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
82 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
83 }
84 
85 void
ieee80211_adhoc_detach(struct ieee80211com * ic)86 ieee80211_adhoc_detach(struct ieee80211com *ic)
87 {
88 }
89 
90 static void
adhoc_vdetach(struct ieee80211vap * vap)91 adhoc_vdetach(struct ieee80211vap *vap)
92 {
93 }
94 
95 static void
adhoc_vattach(struct ieee80211vap * vap)96 adhoc_vattach(struct ieee80211vap *vap)
97 {
98 	vap->iv_newstate = adhoc_newstate;
99 	vap->iv_input = adhoc_input;
100 	if (vap->iv_opmode == IEEE80211_M_IBSS)
101 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
102 	else
103 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
104 	vap->iv_recv_ctl = adhoc_recv_ctl;
105 	vap->iv_opdetach = adhoc_vdetach;
106 #ifdef IEEE80211_SUPPORT_TDMA
107 	/*
108 	 * Throw control to tdma support.  Note we do this
109 	 * after setting up our callbacks so it can piggyback
110 	 * on top of us.
111 	 */
112 	if (vap->iv_caps & IEEE80211_C_TDMA)
113 		ieee80211_tdma_vattach(vap);
114 #endif
115 }
116 
117 static void
sta_leave(void * arg,struct ieee80211_node * ni)118 sta_leave(void *arg, struct ieee80211_node *ni)
119 {
120 	struct ieee80211vap *vap = ni->ni_vap;
121 
122 	if (ni != vap->iv_bss)
123 		ieee80211_node_leave(ni);
124 }
125 
126 /*
127  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
128  */
129 static int
adhoc_newstate(struct ieee80211vap * vap,enum ieee80211_state nstate,int arg)130 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
131 {
132 	struct ieee80211com *ic = vap->iv_ic;
133 	struct ieee80211_node *ni;
134 	enum ieee80211_state ostate;
135 
136 	IEEE80211_LOCK_ASSERT(vap->iv_ic);
137 
138 	ostate = vap->iv_state;
139 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
140 	    __func__, ieee80211_state_name[ostate],
141 	    ieee80211_state_name[nstate], arg);
142 	vap->iv_state = nstate;			/* state transition */
143 	if (ostate != IEEE80211_S_SCAN)
144 		ieee80211_cancel_scan(vap);	/* background scan */
145 	ni = vap->iv_bss;			/* NB: no reference held */
146 	switch (nstate) {
147 	case IEEE80211_S_INIT:
148 		switch (ostate) {
149 		case IEEE80211_S_SCAN:
150 			ieee80211_cancel_scan(vap);
151 			break;
152 		default:
153 			break;
154 		}
155 		if (ostate != IEEE80211_S_INIT) {
156 			/* NB: optimize INIT -> INIT case */
157 			ieee80211_reset_bss(vap);
158 		}
159 		break;
160 	case IEEE80211_S_SCAN:
161 		switch (ostate) {
162 		case IEEE80211_S_RUN:		/* beacon miss */
163 			/* purge station table; entries are stale */
164 			ieee80211_iterate_nodes_vap(&ic->ic_sta, vap,
165 			    sta_leave, NULL);
166 			/* fall thru... */
167 		case IEEE80211_S_INIT:
168 			if (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
169 			    !IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
170 				/*
171 				 * Already have a channel; bypass the
172 				 * scan and startup immediately.
173 				 */
174 				ieee80211_create_ibss(vap,
175 				    ieee80211_ht_adjust_channel(ic,
176 				    vap->iv_des_chan, vap->iv_flags_ht));
177 				break;
178 			}
179 			/*
180 			 * Initiate a scan.  We can come here as a result
181 			 * of an IEEE80211_IOC_SCAN_REQ too in which case
182 			 * the vap will be marked with IEEE80211_FEXT_SCANREQ
183 			 * and the scan request parameters will be present
184 			 * in iv_scanreq.  Otherwise we do the default.
185 			 */
186 			if (vap->iv_flags_ext & IEEE80211_FEXT_SCANREQ) {
187 				ieee80211_check_scan(vap,
188 				    vap->iv_scanreq_flags,
189 				    vap->iv_scanreq_duration,
190 				    vap->iv_scanreq_mindwell,
191 				    vap->iv_scanreq_maxdwell,
192 				    vap->iv_scanreq_nssid, vap->iv_scanreq_ssid);
193 				vap->iv_flags_ext &= ~IEEE80211_FEXT_SCANREQ;
194 			} else
195 				ieee80211_check_scan_current(vap);
196 			break;
197 		case IEEE80211_S_SCAN:
198 			/*
199 			 * This can happen because of a change in state
200 			 * that requires a reset.  Trigger a new scan
201 			 * unless we're in manual roaming mode in which
202 			 * case an application must issue an explicit request.
203 			 */
204 			if (vap->iv_roaming == IEEE80211_ROAMING_AUTO)
205 				ieee80211_check_scan_current(vap);
206 			break;
207 		default:
208 			goto invalid;
209 		}
210 		break;
211 	case IEEE80211_S_RUN:
212 		if (vap->iv_flags & IEEE80211_F_WPA) {
213 			/* XXX validate prerequisites */
214 		}
215 		switch (ostate) {
216 		case IEEE80211_S_INIT:
217 			/*
218 			 * Already have a channel; bypass the
219 			 * scan and startup immediately.
220 			 * Note that ieee80211_create_ibss will call
221 			 * back to do a RUN->RUN state change.
222 			 */
223 			ieee80211_create_ibss(vap,
224 			    ieee80211_ht_adjust_channel(ic,
225 				ic->ic_curchan, vap->iv_flags_ht));
226 			/* NB: iv_bss is changed on return */
227 			ni = vap->iv_bss;
228 			break;
229 		case IEEE80211_S_SCAN:
230 #ifdef IEEE80211_DEBUG
231 			if (ieee80211_msg_debug(vap)) {
232 				ieee80211_note(vap,
233 				    "synchronized with %s ssid ",
234 				    ether_sprintf(ni->ni_bssid));
235 				ieee80211_print_essid(vap->iv_bss->ni_essid,
236 				    ni->ni_esslen);
237 				net80211_printf(" channel %d start %uMbit/s\n",
238 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
239 				    ieee80211_node_get_txrate_kbit(ni) / 1000);
240 			}
241 #endif
242 			break;
243 		case IEEE80211_S_RUN:	/* IBSS merge */
244 			break;
245 		default:
246 			goto invalid;
247 		}
248 		/*
249 		 * When 802.1x is not in use mark the port authorized
250 		 * at this point so traffic can flow.
251 		 */
252 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
253 			ieee80211_node_authorize(ni);
254 		/*
255 		 * Fake association when joining an existing bss.
256 		 */
257 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
258 		    ic->ic_newassoc != NULL)
259 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
260 		break;
261 	case IEEE80211_S_SLEEP:
262 		vap->iv_sta_ps(vap, 0);
263 		break;
264 	default:
265 	invalid:
266 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
267 		    "%s: unexpected state transition %s -> %s\n", __func__,
268 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
269 		break;
270 	}
271 	return 0;
272 }
273 
274 /*
275  * Decide if a received management frame should be
276  * printed when debugging is enabled.  This filters some
277  * of the less interesting frames that come frequently
278  * (e.g. beacons).
279  */
280 static __inline int
doprint(struct ieee80211vap * vap,int subtype)281 doprint(struct ieee80211vap *vap, int subtype)
282 {
283 	switch (subtype) {
284 	case IEEE80211_FC0_SUBTYPE_BEACON:
285 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
286 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
287 		return 1;
288 	}
289 	return 1;
290 }
291 
292 /*
293  * Process a received frame.  The node associated with the sender
294  * should be supplied.  If nothing was found in the node table then
295  * the caller is assumed to supply a reference to iv_bss instead.
296  * The RSSI and a timestamp are also supplied.  The RSSI data is used
297  * during AP scanning to select a AP to associate with; it can have
298  * any units so long as values have consistent units and higher values
299  * mean ``better signal''.  The receive timestamp is currently not used
300  * by the 802.11 layer.
301  */
302 static int
adhoc_input(struct ieee80211_node * ni,struct mbuf * m,const struct ieee80211_rx_stats * rxs,int rssi,int nf)303 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
304     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
305 {
306 	struct ieee80211vap *vap = ni->ni_vap;
307 	struct ieee80211com *ic = ni->ni_ic;
308 	struct ifnet *ifp = vap->iv_ifp;
309 	struct ieee80211_frame *wh;
310 	struct ieee80211_key *key;
311 	struct ether_header *eh;
312 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
313 	uint8_t dir, type, subtype, qos;
314 	uint8_t *bssid;
315 	int is_hw_decrypted = 0;
316 	int has_decrypted = 0;
317 
318 	/*
319 	 * Some devices do hardware decryption all the way through
320 	 * to pretending the frame wasn't encrypted in the first place.
321 	 * So, tag it appropriately so it isn't discarded inappropriately.
322 	 */
323 	if ((rxs != NULL) && (rxs->c_pktflags & IEEE80211_RX_F_DECRYPTED))
324 		is_hw_decrypted = 1;
325 
326 	if (m->m_flags & M_AMPDU_MPDU) {
327 		/*
328 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
329 		 * w/ M_AMPDU_MPDU marked have already passed through
330 		 * here but were received out of order and been held on
331 		 * the reorder queue.  When resubmitted they are marked
332 		 * with the M_AMPDU_MPDU flag and we can bypass most of
333 		 * the normal processing.
334 		 */
335 		wh = mtod(m, struct ieee80211_frame *);
336 		type = IEEE80211_FC0_TYPE_DATA;
337 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
338 		subtype = IEEE80211_FC0_SUBTYPE_QOS_DATA;
339 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
340 		goto resubmit_ampdu;
341 	}
342 
343 	KASSERT(ni != NULL, ("null node"));
344 	ni->ni_inact = ni->ni_inact_reload;
345 
346 	type = -1;			/* undefined */
347 
348 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
349 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
350 		    ni->ni_macaddr, NULL,
351 		    "too short (1): len %u", m->m_pkthdr.len);
352 		vap->iv_stats.is_rx_tooshort++;
353 		goto out;
354 	}
355 	/*
356 	 * Bit of a cheat here, we use a pointer for a 3-address
357 	 * frame format but don't reference fields past outside
358 	 * ieee80211_frame_min w/o first validating the data is
359 	 * present.
360 	 */
361 	wh = mtod(m, struct ieee80211_frame *);
362 
363 	if (!IEEE80211_IS_FC0_CHECK_VER(wh, IEEE80211_FC0_VERSION_0)) {
364 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
365 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
366 		    wh->i_fc[0], wh->i_fc[1]);
367 		vap->iv_stats.is_rx_badversion++;
368 		goto err;
369 	}
370 
371 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
372 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
373 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
374 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
375 		if (dir != IEEE80211_FC1_DIR_NODS)
376 			bssid = wh->i_addr1;
377 		else if (type == IEEE80211_FC0_TYPE_CTL)
378 			bssid = wh->i_addr1;
379 		else {
380 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
381 				IEEE80211_DISCARD_MAC(vap,
382 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
383 				    NULL, "too short (2): len %u",
384 				    m->m_pkthdr.len);
385 				vap->iv_stats.is_rx_tooshort++;
386 				goto out;
387 			}
388 			bssid = wh->i_addr3;
389 		}
390 		/*
391 		 * Validate the bssid.
392 		 */
393 		if (!(type == IEEE80211_FC0_TYPE_MGT &&
394 		     (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
395 		      subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) &&
396 		    !IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
397 		    !IEEE80211_ADDR_EQ(bssid,
398 		        ieee80211_vap_get_broadcast_address(vap))) {
399 			/* not interested in */
400 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
401 			    bssid, NULL, "%s", "not to bss");
402 			vap->iv_stats.is_rx_wrongbss++;
403 			goto out;
404 		}
405 		/*
406 		 * Data frame, cons up a node when it doesn't
407 		 * exist. This should probably done after an ACL check.
408 		 */
409 		if (type == IEEE80211_FC0_TYPE_DATA &&
410 		    ni == vap->iv_bss &&
411 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
412 			/*
413 			 * Beware of frames that come in too early; we
414 			 * can receive broadcast frames and creating sta
415 			 * entries will blow up because there is no bss
416 			 * channel yet.
417 			 */
418 			if (vap->iv_state != IEEE80211_S_RUN) {
419 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
420 				    wh, "data", "not in RUN state (%s)",
421 				    ieee80211_state_name[vap->iv_state]);
422 				vap->iv_stats.is_rx_badstate++;
423 				goto err;
424 			}
425 			/*
426 			 * Fake up a node for this newly discovered member
427 			 * of the IBSS.
428 			 *
429 			 * Note: This doesn't "upgrade" the node to 11n;
430 			 * that will happen after a probe request/response
431 			 * exchange.
432 			 */
433 			ni = ieee80211_fakeup_adhoc_node(vap, wh->i_addr2);
434 			if (ni == NULL) {
435 				/* NB: stat kept for alloc failure */
436 				goto err;
437 			}
438 		}
439 		IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
440 		ni->ni_noise = nf;
441 		if (IEEE80211_HAS_SEQ(type, subtype) &&
442 		    IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
443 			uint8_t tid = ieee80211_gettid(wh);
444 			if (IEEE80211_QOS_HAS_SEQ(wh) &&
445 			    TID_TO_WME_AC(tid) >= WME_AC_VI)
446 				ic->ic_wme.wme_hipri_traffic++;
447 			if (! ieee80211_check_rxseq(ni, wh, bssid, rxs))
448 				goto out;
449 		}
450 	}
451 
452 	switch (type) {
453 	case IEEE80211_FC0_TYPE_DATA:
454 		hdrspace = ieee80211_hdrspace(ic, wh);
455 		if (m->m_len < hdrspace &&
456 		    (m = m_pullup(m, hdrspace)) == NULL) {
457 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
458 			    ni->ni_macaddr, NULL,
459 			    "data too short: expecting %u", hdrspace);
460 			vap->iv_stats.is_rx_tooshort++;
461 			goto out;		/* XXX */
462 		}
463 		if (dir != IEEE80211_FC1_DIR_NODS) {
464 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
465 			    wh, "data", "incorrect dir 0x%x", dir);
466 			vap->iv_stats.is_rx_wrongdir++;
467 			goto out;
468 		}
469 		/* XXX no power-save support */
470 
471 		/*
472 		 * Handle A-MPDU re-ordering.  If the frame is to be
473 		 * processed directly then ieee80211_ampdu_reorder
474 		 * will return 0; otherwise it has consumed the mbuf
475 		 * and we should do nothing more with it.
476 		 */
477 		if ((m->m_flags & M_AMPDU) &&
478 		    ieee80211_ampdu_reorder(ni, m, rxs) != 0) {
479 			m = NULL;
480 			goto out;
481 		}
482 	resubmit_ampdu:
483 
484 		/*
485 		 * Handle privacy requirements.  Note that we
486 		 * must not be preempted from here until after
487 		 * we (potentially) call ieee80211_crypto_demic;
488 		 * otherwise we may violate assumptions in the
489 		 * crypto cipher modules used to do delayed update
490 		 * of replay sequence numbers.
491 		 */
492 		if (is_hw_decrypted || IEEE80211_IS_PROTECTED(wh)) {
493 			if ((vap->iv_flags & IEEE80211_F_PRIVACY) == 0) {
494 				/*
495 				 * Discard encrypted frames when privacy is off.
496 				 */
497 				IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
498 				    wh, "WEP", "%s", "PRIVACY off");
499 				vap->iv_stats.is_rx_noprivacy++;
500 				IEEE80211_NODE_STAT(ni, rx_noprivacy);
501 				goto out;
502 			}
503 			if (ieee80211_crypto_decap(ni, m, hdrspace, &key) == 0) {
504 				/* NB: stats+msgs handled in crypto_decap */
505 				IEEE80211_NODE_STAT(ni, rx_wepfail);
506 				goto out;
507 			}
508 			wh = mtod(m, struct ieee80211_frame *);
509 			wh->i_fc[1] &= ~IEEE80211_FC1_PROTECTED;
510 			has_decrypted = 1;
511 		} else {
512 			/* XXX M_WEP and IEEE80211_F_PRIVACY */
513 			key = NULL;
514 		}
515 
516 		/*
517 		 * Save QoS bits for use below--before we strip the header.
518 		 */
519 		if (subtype == IEEE80211_FC0_SUBTYPE_QOS_DATA)
520 			qos = ieee80211_getqos(wh)[0];
521 		else
522 			qos = 0;
523 
524 		/*
525 		 * Next up, any fragmentation.
526 		 */
527 		if (!IEEE80211_IS_MULTICAST(wh->i_addr1)) {
528 			m = ieee80211_defrag(ni, m, hdrspace, has_decrypted);
529 			if (m == NULL) {
530 				/* Fragment dropped or frame not complete yet */
531 				goto out;
532 			}
533 		}
534 		wh = NULL;		/* no longer valid, catch any uses */
535 
536 		/*
537 		 * Next strip any MSDU crypto bits.
538 		 */
539 		if (!ieee80211_crypto_demic(vap, key, m, 0)) {
540 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
541 			    ni->ni_macaddr, "data", "%s", "demic error");
542 			vap->iv_stats.is_rx_demicfail++;
543 			IEEE80211_NODE_STAT(ni, rx_demicfail);
544 			goto out;
545 		}
546 
547 		/* copy to listener after decrypt */
548 		if (ieee80211_radiotap_active_vap(vap))
549 			ieee80211_radiotap_rx(vap, m);
550 		need_tap = 0;
551 
552 		/*
553 		 * Finally, strip the 802.11 header.
554 		 */
555 		m = ieee80211_decap(vap, m, hdrspace, qos);
556 		if (m == NULL) {
557 			/* XXX mask bit to check for both */
558 			/* don't count Null data frames as errors */
559 			if (subtype == IEEE80211_FC0_SUBTYPE_NODATA ||
560 			    subtype == IEEE80211_FC0_SUBTYPE_QOS_NULL)
561 				goto out;
562 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
563 			    ni->ni_macaddr, "data", "%s", "decap error");
564 			vap->iv_stats.is_rx_decap++;
565 			IEEE80211_NODE_STAT(ni, rx_decap);
566 			goto err;
567 		}
568 		if (!(qos & IEEE80211_QOS_AMSDU))
569 			eh = mtod(m, struct ether_header *);
570 		else
571 			eh = NULL;
572 		if (!ieee80211_node_is_authorized(ni)) {
573 			/*
574 			 * Deny any non-PAE frames received prior to
575 			 * authorization.  For open/shared-key
576 			 * authentication the port is mark authorized
577 			 * after authentication completes.  For 802.1x
578 			 * the port is not marked authorized by the
579 			 * authenticator until the handshake has completed.
580 			 */
581 			if (eh == NULL ||
582 			    eh->ether_type != htons(ETHERTYPE_PAE)) {
583 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_INPUT,
584 				    ni->ni_macaddr, "data", "unauthorized or "
585 				    "unknown port: ether type 0x%x len %u",
586 				    eh == NULL ? -1 : eh->ether_type,
587 				    m->m_pkthdr.len);
588 				vap->iv_stats.is_rx_unauth++;
589 				IEEE80211_NODE_STAT(ni, rx_unauth);
590 				goto err;
591 			}
592 		} else {
593 			/*
594 			 * When denying unencrypted frames, discard
595 			 * any non-PAE frames received without encryption.
596 			 */
597 			if ((vap->iv_flags & IEEE80211_F_DROPUNENC) &&
598 			    ((has_decrypted == 0) && (m->m_flags & M_WEP) == 0) &&
599 			    (is_hw_decrypted == 0) &&
600 			    (eh == NULL ||
601 			     eh->ether_type != htons(ETHERTYPE_PAE))) {
602 				/*
603 				 * Drop unencrypted frames.
604 				 */
605 				vap->iv_stats.is_rx_unencrypted++;
606 				IEEE80211_NODE_STAT(ni, rx_unencrypted);
607 				goto out;
608 			}
609 		}
610 		/* XXX require HT? */
611 		if (qos & IEEE80211_QOS_AMSDU) {
612 			m = ieee80211_decap_amsdu(ni, m);
613 			if (m == NULL)
614 				return IEEE80211_FC0_TYPE_DATA;
615 		} else {
616 #ifdef IEEE80211_SUPPORT_SUPERG
617 			m = ieee80211_decap_fastframe(vap, ni, m);
618 			if (m == NULL)
619 				return IEEE80211_FC0_TYPE_DATA;
620 #endif
621 		}
622 		if (dir == IEEE80211_FC1_DIR_DSTODS && ni->ni_wdsvap != NULL)
623 			ieee80211_deliver_data(ni->ni_wdsvap, ni, m);
624 		else
625 			ieee80211_deliver_data(vap, ni, m);
626 		return IEEE80211_FC0_TYPE_DATA;
627 
628 	case IEEE80211_FC0_TYPE_MGT:
629 		vap->iv_stats.is_rx_mgmt++;
630 		IEEE80211_NODE_STAT(ni, rx_mgmt);
631 		if (dir != IEEE80211_FC1_DIR_NODS) {
632 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
633 			    wh, "data", "incorrect dir 0x%x", dir);
634 			vap->iv_stats.is_rx_wrongdir++;
635 			goto err;
636 		}
637 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
638 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
639 			    ni->ni_macaddr, "mgt", "too short: len %u",
640 			    m->m_pkthdr.len);
641 			vap->iv_stats.is_rx_tooshort++;
642 			goto out;
643 		}
644 #ifdef IEEE80211_DEBUG
645 		if ((ieee80211_msg_debug(vap) && doprint(vap, subtype)) ||
646 		    ieee80211_msg_dumppkts(vap)) {
647 			net80211_vap_printf(vap,
648 			    "received %s from %s rssi %d\n",
649 			    ieee80211_mgt_subtype_name(subtype),
650 			    ether_sprintf(wh->i_addr2), rssi);
651 		}
652 #endif
653 		if (IEEE80211_IS_PROTECTED(wh)) {
654 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
655 			    wh, NULL, "%s", "WEP set but not permitted");
656 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
657 			goto out;
658 		}
659 		vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
660 		goto out;
661 
662 	case IEEE80211_FC0_TYPE_CTL:
663 		vap->iv_stats.is_rx_ctl++;
664 		IEEE80211_NODE_STAT(ni, rx_ctrl);
665 		if (ieee80211_is_ctl_frame_for_vap(ni, m))
666 			vap->iv_recv_ctl(ni, m, subtype);
667 		goto out;
668 
669 	default:
670 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
671 		    wh, "bad", "frame type 0x%x", type);
672 		/* should not come here */
673 		break;
674 	}
675 err:
676 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
677 out:
678 	if (m != NULL) {
679 		if (need_tap && ieee80211_radiotap_active_vap(vap))
680 			ieee80211_radiotap_rx(vap, m);
681 		m_freem(m);
682 	}
683 	return type;
684 }
685 
686 static int
is11bclient(const uint8_t * rates,const uint8_t * xrates)687 is11bclient(const uint8_t *rates, const uint8_t *xrates)
688 {
689 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
690 	int i;
691 
692 	/* NB: the 11b clients we care about will not have xrates */
693 	if (xrates != NULL || rates == NULL)
694 		return 0;
695 	for (i = 0; i < rates[1]; i++) {
696 		int r = rates[2+i] & IEEE80211_RATE_VAL;
697 		if (r > 2*11 || ((1<<r) & brates) == 0)
698 			return 0;
699 	}
700 	return 1;
701 }
702 
703 static void
adhoc_recv_mgmt(struct ieee80211_node * ni,struct mbuf * m0,int subtype,const struct ieee80211_rx_stats * rxs,int rssi,int nf)704 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
705 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
706 {
707 	struct ieee80211vap *vap = ni->ni_vap;
708 	struct ieee80211com *ic = ni->ni_ic;
709 	struct ieee80211_channel *rxchan = ic->ic_curchan;
710 	struct ieee80211_frame *wh;
711 	uint8_t *frm, *efrm;
712 	uint8_t *ssid, *rates, *xrates;
713 #if 0
714 	int ht_state_change = 0;
715 #endif
716 
717 	wh = mtod(m0, struct ieee80211_frame *);
718 	frm = (uint8_t *)&wh[1];
719 	efrm = mtod(m0, uint8_t *) + m0->m_len;
720 
721 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
722 	    "%s: recv mgmt frame, addr2=%6D, ni=%p (%6D) fc=%.02x %.02x\n",
723 	    __func__,
724 	    wh->i_addr2, ":",
725 	    ni,
726 	    ni->ni_macaddr, ":",
727 	    wh->i_fc[0],
728 	    wh->i_fc[1]);
729 	switch (subtype) {
730 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
731 	case IEEE80211_FC0_SUBTYPE_BEACON: {
732 		struct ieee80211_scanparams scan;
733 		struct ieee80211_channel *c;
734 		/*
735 		 * We process beacon/probe response
736 		 * frames to discover neighbors.
737 		 */
738 		if (rxs != NULL) {
739 			c = ieee80211_lookup_channel_rxstatus(vap, rxs);
740 			if (c != NULL)
741 				rxchan = c;
742 		}
743 		if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
744 			return;
745 		/*
746 		 * Count frame now that we know it's to be processed.
747 		 */
748 		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
749 			vap->iv_stats.is_rx_beacon++;		/* XXX remove */
750 			IEEE80211_NODE_STAT(ni, rx_beacons);
751 		} else
752 			IEEE80211_NODE_STAT(ni, rx_proberesp);
753 		/*
754 		 * If scanning, just pass information to the scan module.
755 		 */
756 		if (ic->ic_flags & IEEE80211_F_SCAN) {
757 			if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
758 				/*
759 				 * Actively scanning a channel marked passive;
760 				 * send a probe request now that we know there
761 				 * is 802.11 traffic present.
762 				 *
763 				 * XXX check if the beacon we recv'd gives
764 				 * us what we need and suppress the probe req
765 				 */
766 				ieee80211_probe_curchan(vap, true);
767 				ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
768 			}
769 			ieee80211_add_scan(vap, rxchan, &scan, wh,
770 			    subtype, rssi, nf);
771 			return;
772 		}
773 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
774 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
775 				/*
776 				 * Create a new entry in the neighbor table.
777 				 *
778 				 * XXX TODO:
779 				 *
780 				 * Here we're not scanning; so if we have an
781 				 * SSID then make sure it matches our SSID.
782 				 * Otherwise this code will match on all IBSS
783 				 * beacons/probe requests for all SSIDs,
784 				 * filling the node table with nodes that
785 				 * aren't ours.
786 				 */
787 				if (ieee80211_ibss_node_check_new(ni, &scan)) {
788 					ni = ieee80211_add_neighbor(vap, wh, &scan);
789 					/*
790 					 * Send a probe request so we announce 11n
791 					 * capabilities.
792 					 */
793 					ieee80211_send_probereq(ni, /* node */
794 					    vap->iv_myaddr, /* SA */
795 					    ni->ni_macaddr, /* DA */
796 					    vap->iv_bss->ni_bssid, /* BSSID */
797 					    vap->iv_bss->ni_essid,
798 					    vap->iv_bss->ni_esslen); /* SSID */
799 				} else
800 					ni = NULL;
801 
802 				/*
803 				 * Send a probe request so we announce 11n
804 				 * capabilities.
805 				 *
806 				 * Don't do this if we're scanning.
807 				 */
808 				if (! (ic->ic_flags & IEEE80211_F_SCAN))
809 					ieee80211_send_probereq(ni, /* node */
810 						vap->iv_myaddr, /* SA */
811 						ni->ni_macaddr, /* DA */
812 						vap->iv_bss->ni_bssid, /* BSSID */
813 						vap->iv_bss->ni_essid,
814 						vap->iv_bss->ni_esslen); /* SSID */
815 
816 			} else if (ni->ni_capinfo == 0) {
817 				/*
818 				 * Update faked node created on transmit.
819 				 * Note this also updates the tsf.
820 				 */
821 				ieee80211_init_neighbor(ni, wh, &scan);
822 
823 				/*
824 				 * Send a probe request so we announce 11n
825 				 * capabilities.
826 				 */
827 				ieee80211_send_probereq(ni, /* node */
828 					vap->iv_myaddr, /* SA */
829 					ni->ni_macaddr, /* DA */
830 					vap->iv_bss->ni_bssid, /* BSSID */
831 					vap->iv_bss->ni_essid,
832 					vap->iv_bss->ni_esslen); /* SSID */
833 			} else {
834 				/*
835 				 * Record tsf for potential resync.
836 				 */
837 				memcpy(ni->ni_tstamp.data, scan.tstamp,
838 					sizeof(ni->ni_tstamp));
839 			}
840 			/*
841 			 * This isn't enabled yet - otherwise it would
842 			 * update the HT parameters and channel width
843 			 * from any node, which could lead to lots of
844 			 * strange behaviour if the 11n nodes aren't
845 			 * exactly configured to match.
846 			 */
847 #if 0
848 			if (scan.htcap != NULL && scan.htinfo != NULL &&
849 			    (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
850 				ieee80211_ht_updateparams(ni,
851 				    scan.htcap, scan.htinfo));
852 				if (ieee80211_ht_updateparams_final(ni,
853 				    scan.htcap, scan.htinfo))
854 					ht_state_change = 1;
855 			}
856 
857 			/* XXX same for VHT? */
858 #endif
859 			if (ni != NULL) {
860 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
861 				ni->ni_noise = nf;
862 			}
863 			/*
864 			 * Same here - the channel width change should
865 			 * be applied to the specific peer node, not
866 			 * to the ic.  Ie, the interface configuration
867 			 * should stay in its current channel width;
868 			 * but it should change the rate control and
869 			 * any queued frames for the given node only.
870 			 *
871 			 * Since there's no (current) way to inform
872 			 * the driver that a channel width change has
873 			 * occurred for a single node, just stub this
874 			 * out.
875 			 */
876 #if 0
877 			if (ht_state_change)
878 				ieee80211_update_chw(ic);
879 #endif
880 		}
881 		break;
882 	}
883 
884 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
885 		if (vap->iv_state != IEEE80211_S_RUN) {
886 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
887 			    wh, NULL, "wrong state %s",
888 			    ieee80211_state_name[vap->iv_state]);
889 			vap->iv_stats.is_rx_mgtdiscard++;
890 			return;
891 		}
892 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
893 			/* frame must be directed */
894 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
895 			    wh, NULL, "%s", "not unicast");
896 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
897 			return;
898 		}
899 
900 		/*
901 		 * prreq frame format
902 		 *	[tlv] ssid
903 		 *	[tlv] supported rates
904 		 *	[tlv] extended supported rates
905 		 */
906 		ssid = rates = xrates = NULL;
907 		while (efrm - frm > 1) {
908 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
909 			switch (*frm) {
910 			case IEEE80211_ELEMID_SSID:
911 				ssid = frm;
912 				break;
913 			case IEEE80211_ELEMID_RATES:
914 				rates = frm;
915 				break;
916 			case IEEE80211_ELEMID_XRATES:
917 				xrates = frm;
918 				break;
919 			}
920 			frm += frm[1] + 2;
921 		}
922 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
923 		if (xrates != NULL)
924 			IEEE80211_VERIFY_ELEMENT(xrates,
925 				IEEE80211_RATE_MAXSIZE - rates[1], return);
926 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
927 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
928 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
929 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
930 			    wh, NULL,
931 			    "%s", "no ssid with ssid suppression enabled");
932 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
933 			return;
934 		}
935 
936 		/* XXX find a better class or define it's own */
937 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
938 		    "%s", "recv probe req");
939 		/*
940 		 * Some legacy 11b clients cannot hack a complete
941 		 * probe response frame.  When the request includes
942 		 * only a bare-bones rate set, communicate this to
943 		 * the transmit side.
944 		 */
945 		ieee80211_send_proberesp(vap, wh->i_addr2,
946 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
947 
948 		/*
949 		 * Note: we don't benefit from stashing the probe request
950 		 * IEs away to use for IBSS negotiation, because we
951 		 * typically don't get all of the IEs.
952 		 */
953 		break;
954 
955 	case IEEE80211_FC0_SUBTYPE_ACTION:
956 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
957 		if ((ni == vap->iv_bss) &&
958 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
959 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
960 			    wh, NULL, "%s", "unknown node");
961 			vap->iv_stats.is_rx_mgtdiscard++;
962 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
963 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
964 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
965 			    wh, NULL, "%s", "not for us");
966 			vap->iv_stats.is_rx_mgtdiscard++;
967 		} else if (vap->iv_state != IEEE80211_S_RUN) {
968 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
969 			    wh, NULL, "wrong state %s",
970 			    ieee80211_state_name[vap->iv_state]);
971 			vap->iv_stats.is_rx_mgtdiscard++;
972 		} else {
973 			if (ieee80211_parse_action(ni, m0) == 0)
974 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
975 		}
976 		break;
977 
978 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
979 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
980 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
981 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
982 	case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
983 	case IEEE80211_FC0_SUBTYPE_ATIM:
984 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
985 	case IEEE80211_FC0_SUBTYPE_AUTH:
986 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
987 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
988 		    wh, NULL, "%s", "not handled");
989 		vap->iv_stats.is_rx_mgtdiscard++;
990 		break;
991 
992 	default:
993 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
994 		    wh, "mgt", "subtype 0x%x not handled", subtype);
995 		vap->iv_stats.is_rx_badsubtype++;
996 		break;
997 	}
998 }
999 #undef IEEE80211_VERIFY_LENGTH
1000 #undef IEEE80211_VERIFY_ELEMENT
1001 
1002 static void
ahdemo_recv_mgmt(struct ieee80211_node * ni,struct mbuf * m0,int subtype,const struct ieee80211_rx_stats * rxs,int rssi,int nf)1003 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
1004 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
1005 {
1006 	struct ieee80211vap *vap = ni->ni_vap;
1007 	struct ieee80211com *ic = ni->ni_ic;
1008 
1009 	/*
1010 	 * Process management frames when scanning; useful for doing
1011 	 * a site-survey.
1012 	 */
1013 	if (ic->ic_flags & IEEE80211_F_SCAN)
1014 		adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
1015 	else {
1016 #ifdef IEEE80211_DEBUG
1017 		struct ieee80211_frame *wh;
1018 
1019 		wh = mtod(m0, struct ieee80211_frame *);
1020 #endif
1021 		switch (subtype) {
1022 		case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1023 		case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1024 		case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1025 		case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1026 		case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
1027 		case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1028 		case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
1029 		case IEEE80211_FC0_SUBTYPE_BEACON:
1030 		case IEEE80211_FC0_SUBTYPE_ATIM:
1031 		case IEEE80211_FC0_SUBTYPE_DISASSOC:
1032 		case IEEE80211_FC0_SUBTYPE_AUTH:
1033 		case IEEE80211_FC0_SUBTYPE_DEAUTH:
1034 		case IEEE80211_FC0_SUBTYPE_ACTION:
1035 		case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
1036 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
1037 			     wh, NULL, "%s", "not handled");
1038 			vap->iv_stats.is_rx_mgtdiscard++;
1039 			break;
1040 		default:
1041 			IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
1042 			     wh, "mgt", "subtype 0x%x not handled", subtype);
1043 			vap->iv_stats.is_rx_badsubtype++;
1044 			break;
1045 		}
1046 	}
1047 }
1048 
1049 static void
adhoc_recv_ctl(struct ieee80211_node * ni,struct mbuf * m,int subtype)1050 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
1051 {
1052 
1053 	switch (subtype) {
1054 	case IEEE80211_FC0_SUBTYPE_BAR:
1055 		ieee80211_recv_bar(ni, m);
1056 		break;
1057 	}
1058 }
1059