xref: /freebsd/sys/net80211/ieee80211_adhoc.c (revision 38075f7d5c87176f7b317c368712444a2f450a5e)
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/if_private.h>
52 #include <net/ethernet.h>
53 
54 #include <net/bpf.h>
55 
56 #include <net80211/ieee80211_var.h>
57 #include <net80211/ieee80211_adhoc.h>
58 #include <net80211/ieee80211_input.h>
59 #ifdef IEEE80211_SUPPORT_SUPERG
60 #include <net80211/ieee80211_superg.h>
61 #endif
62 #ifdef IEEE80211_SUPPORT_TDMA
63 #include <net80211/ieee80211_tdma.h>
64 #endif
65 #include <net80211/ieee80211_sta.h>
66 
67 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
68 
69 static	void adhoc_vattach(struct ieee80211vap *);
70 static	int adhoc_newstate(struct ieee80211vap *, enum ieee80211_state, int);
71 static int adhoc_input(struct ieee80211_node *, struct mbuf *,
72 	    const struct ieee80211_rx_stats *, int, int);
73 static void adhoc_recv_mgmt(struct ieee80211_node *, struct mbuf *,
74 	int subtype, const struct ieee80211_rx_stats *, int, int);
75 static void ahdemo_recv_mgmt(struct ieee80211_node *, struct mbuf *,
76 	    int subtype, const struct ieee80211_rx_stats *rxs, int, int);
77 static void adhoc_recv_ctl(struct ieee80211_node *, struct mbuf *, int subtype);
78 
79 void
ieee80211_adhoc_attach(struct ieee80211com * ic)80 ieee80211_adhoc_attach(struct ieee80211com *ic)
81 {
82 	ic->ic_vattach[IEEE80211_M_IBSS] = adhoc_vattach;
83 	ic->ic_vattach[IEEE80211_M_AHDEMO] = adhoc_vattach;
84 }
85 
86 void
ieee80211_adhoc_detach(struct ieee80211com * ic)87 ieee80211_adhoc_detach(struct ieee80211com *ic)
88 {
89 }
90 
91 static void
adhoc_vdetach(struct ieee80211vap * vap)92 adhoc_vdetach(struct ieee80211vap *vap)
93 {
94 }
95 
96 static void
adhoc_vattach(struct ieee80211vap * vap)97 adhoc_vattach(struct ieee80211vap *vap)
98 {
99 	vap->iv_newstate = adhoc_newstate;
100 	vap->iv_input = adhoc_input;
101 	if (vap->iv_opmode == IEEE80211_M_IBSS)
102 		vap->iv_recv_mgmt = adhoc_recv_mgmt;
103 	else
104 		vap->iv_recv_mgmt = ahdemo_recv_mgmt;
105 	vap->iv_recv_ctl = adhoc_recv_ctl;
106 	vap->iv_opdetach = adhoc_vdetach;
107 #ifdef IEEE80211_SUPPORT_TDMA
108 	/*
109 	 * Throw control to tdma support.  Note we do this
110 	 * after setting up our callbacks so it can piggyback
111 	 * on top of us.
112 	 */
113 	if (vap->iv_caps & IEEE80211_C_TDMA)
114 		ieee80211_tdma_vattach(vap);
115 #endif
116 }
117 
118 static void
sta_leave(void * arg,struct ieee80211_node * ni)119 sta_leave(void *arg, struct ieee80211_node *ni)
120 {
121 	struct ieee80211vap *vap = ni->ni_vap;
122 
123 	if (ni != vap->iv_bss)
124 		ieee80211_node_leave(ni);
125 }
126 
127 /*
128  * IEEE80211_M_IBSS+IEEE80211_M_AHDEMO vap state machine handler.
129  */
130 static int
adhoc_newstate(struct ieee80211vap * vap,enum ieee80211_state nstate,int arg)131 adhoc_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
132 {
133 	struct ieee80211com *ic = vap->iv_ic;
134 	struct ieee80211_node *ni;
135 	enum ieee80211_state ostate;
136 
137 	IEEE80211_LOCK_ASSERT(vap->iv_ic);
138 
139 	ostate = vap->iv_state;
140 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE, "%s: %s -> %s (%d)\n",
141 	    __func__, ieee80211_state_name[ostate],
142 	    ieee80211_state_name[nstate], arg);
143 	vap->iv_state = nstate;			/* state transition */
144 	if (ostate != IEEE80211_S_SCAN)
145 		ieee80211_cancel_scan(vap);	/* background scan */
146 	ni = vap->iv_bss;			/* NB: no reference held */
147 	switch (nstate) {
148 	case IEEE80211_S_INIT:
149 		switch (ostate) {
150 		case IEEE80211_S_SCAN:
151 			ieee80211_cancel_scan(vap);
152 			break;
153 		default:
154 			break;
155 		}
156 		if (ostate != IEEE80211_S_INIT) {
157 			/* NB: optimize INIT -> INIT case */
158 			ieee80211_reset_bss(vap);
159 		}
160 		break;
161 	case IEEE80211_S_SCAN:
162 		switch (ostate) {
163 		case IEEE80211_S_RUN:		/* beacon miss */
164 			/* purge station table; entries are stale */
165 			ieee80211_iterate_nodes_vap(&ic->ic_sta, vap,
166 			    sta_leave, NULL);
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_INIT:
218 			/*
219 			 * Already have a channel; bypass the
220 			 * scan and startup immediately.
221 			 * Note that ieee80211_create_ibss will call
222 			 * back to do a RUN->RUN state change.
223 			 */
224 			ieee80211_create_ibss(vap,
225 			    ieee80211_ht_adjust_channel(ic,
226 				ic->ic_curchan, vap->iv_flags_ht));
227 			/* NB: iv_bss is changed on return */
228 			ni = vap->iv_bss;
229 			break;
230 		case IEEE80211_S_SCAN:
231 #ifdef IEEE80211_DEBUG
232 			if (ieee80211_msg_debug(vap)) {
233 				ieee80211_note(vap,
234 				    "synchronized with %s ssid ",
235 				    ether_sprintf(ni->ni_bssid));
236 				ieee80211_print_essid(vap->iv_bss->ni_essid,
237 				    ni->ni_esslen);
238 				printf(" channel %d start %uMbit/s\n",
239 				    ieee80211_chan2ieee(ic, ic->ic_curchan),
240 				    ieee80211_node_get_txrate_kbit(ni) / 1000);
241 			}
242 #endif
243 			break;
244 		case IEEE80211_S_RUN:	/* IBSS merge */
245 			break;
246 		default:
247 			goto invalid;
248 		}
249 		/*
250 		 * When 802.1x is not in use mark the port authorized
251 		 * at this point so traffic can flow.
252 		 */
253 		if (ni->ni_authmode != IEEE80211_AUTH_8021X)
254 			ieee80211_node_authorize(ni);
255 		/*
256 		 * Fake association when joining an existing bss.
257 		 */
258 		if (!IEEE80211_ADDR_EQ(ni->ni_macaddr, vap->iv_myaddr) &&
259 		    ic->ic_newassoc != NULL)
260 			ic->ic_newassoc(ni, ostate != IEEE80211_S_RUN);
261 		break;
262 	case IEEE80211_S_SLEEP:
263 		vap->iv_sta_ps(vap, 0);
264 		break;
265 	default:
266 	invalid:
267 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_STATE,
268 		    "%s: unexpected state transition %s -> %s\n", __func__,
269 		    ieee80211_state_name[ostate], ieee80211_state_name[nstate]);
270 		break;
271 	}
272 	return 0;
273 }
274 
275 /*
276  * Decide if a received management frame should be
277  * printed when debugging is enabled.  This filters some
278  * of the less interesting frames that come frequently
279  * (e.g. beacons).
280  */
281 static __inline int
doprint(struct ieee80211vap * vap,int subtype)282 doprint(struct ieee80211vap *vap, int subtype)
283 {
284 	switch (subtype) {
285 	case IEEE80211_FC0_SUBTYPE_BEACON:
286 		return (vap->iv_ic->ic_flags & IEEE80211_F_SCAN);
287 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
288 		return 1;
289 	}
290 	return 1;
291 }
292 
293 /*
294  * Process a received frame.  The node associated with the sender
295  * should be supplied.  If nothing was found in the node table then
296  * the caller is assumed to supply a reference to iv_bss instead.
297  * The RSSI and a timestamp are also supplied.  The RSSI data is used
298  * during AP scanning to select a AP to associate with; it can have
299  * any units so long as values have consistent units and higher values
300  * mean ``better signal''.  The receive timestamp is currently not used
301  * by the 802.11 layer.
302  */
303 static int
adhoc_input(struct ieee80211_node * ni,struct mbuf * m,const struct ieee80211_rx_stats * rxs,int rssi,int nf)304 adhoc_input(struct ieee80211_node *ni, struct mbuf *m,
305     const struct ieee80211_rx_stats *rxs, int rssi, int nf)
306 {
307 	struct ieee80211vap *vap = ni->ni_vap;
308 	struct ieee80211com *ic = ni->ni_ic;
309 	struct ifnet *ifp = vap->iv_ifp;
310 	struct ieee80211_frame *wh;
311 	struct ieee80211_key *key;
312 	struct ether_header *eh;
313 	int hdrspace, need_tap = 1;	/* mbuf need to be tapped. */
314 	uint8_t dir, type, subtype, qos;
315 	uint8_t *bssid;
316 	int is_hw_decrypted = 0;
317 	int has_decrypted = 0;
318 
319 	/*
320 	 * Some devices do hardware decryption all the way through
321 	 * to pretending the frame wasn't encrypted in the first place.
322 	 * So, tag it appropriately so it isn't discarded inappropriately.
323 	 */
324 	if ((rxs != NULL) && (rxs->c_pktflags & IEEE80211_RX_F_DECRYPTED))
325 		is_hw_decrypted = 1;
326 
327 	if (m->m_flags & M_AMPDU_MPDU) {
328 		/*
329 		 * Fastpath for A-MPDU reorder q resubmission.  Frames
330 		 * w/ M_AMPDU_MPDU marked have already passed through
331 		 * here but were received out of order and been held on
332 		 * the reorder queue.  When resubmitted they are marked
333 		 * with the M_AMPDU_MPDU flag and we can bypass most of
334 		 * the normal processing.
335 		 */
336 		wh = mtod(m, struct ieee80211_frame *);
337 		type = IEEE80211_FC0_TYPE_DATA;
338 		dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
339 		subtype = IEEE80211_FC0_SUBTYPE_QOS_DATA;
340 		hdrspace = ieee80211_hdrspace(ic, wh);	/* XXX optimize? */
341 		goto resubmit_ampdu;
342 	}
343 
344 	KASSERT(ni != NULL, ("null node"));
345 	ni->ni_inact = ni->ni_inact_reload;
346 
347 	type = -1;			/* undefined */
348 
349 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_min)) {
350 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
351 		    ni->ni_macaddr, NULL,
352 		    "too short (1): len %u", m->m_pkthdr.len);
353 		vap->iv_stats.is_rx_tooshort++;
354 		goto out;
355 	}
356 	/*
357 	 * Bit of a cheat here, we use a pointer for a 3-address
358 	 * frame format but don't reference fields past outside
359 	 * ieee80211_frame_min w/o first validating the data is
360 	 * present.
361 	 */
362 	wh = mtod(m, struct ieee80211_frame *);
363 
364 	if (!IEEE80211_IS_FC0_CHECK_VER(wh, IEEE80211_FC0_VERSION_0)) {
365 		IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_ANY,
366 		    ni->ni_macaddr, NULL, "wrong version, fc %02x:%02x",
367 		    wh->i_fc[0], wh->i_fc[1]);
368 		vap->iv_stats.is_rx_badversion++;
369 		goto err;
370 	}
371 
372 	dir = wh->i_fc[1] & IEEE80211_FC1_DIR_MASK;
373 	type = wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK;
374 	subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
375 	if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) {
376 		if (dir != IEEE80211_FC1_DIR_NODS)
377 			bssid = wh->i_addr1;
378 		else if (type == IEEE80211_FC0_TYPE_CTL)
379 			bssid = wh->i_addr1;
380 		else {
381 			if (m->m_pkthdr.len < sizeof(struct ieee80211_frame)) {
382 				IEEE80211_DISCARD_MAC(vap,
383 				    IEEE80211_MSG_ANY, ni->ni_macaddr,
384 				    NULL, "too short (2): len %u",
385 				    m->m_pkthdr.len);
386 				vap->iv_stats.is_rx_tooshort++;
387 				goto out;
388 			}
389 			bssid = wh->i_addr3;
390 		}
391 		/*
392 		 * Validate the bssid.
393 		 */
394 		if (!(type == IEEE80211_FC0_TYPE_MGT &&
395 		     (subtype == IEEE80211_FC0_SUBTYPE_BEACON ||
396 		      subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)) &&
397 		    !IEEE80211_ADDR_EQ(bssid, vap->iv_bss->ni_bssid) &&
398 		    !IEEE80211_ADDR_EQ(bssid, ifp->if_broadcastaddr)) {
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 			if_printf(ifp, "received %s from %s rssi %d\n",
648 			    ieee80211_mgt_subtype_name(subtype),
649 			    ether_sprintf(wh->i_addr2), rssi);
650 		}
651 #endif
652 		if (IEEE80211_IS_PROTECTED(wh)) {
653 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
654 			    wh, NULL, "%s", "WEP set but not permitted");
655 			vap->iv_stats.is_rx_mgtdiscard++; /* XXX */
656 			goto out;
657 		}
658 		vap->iv_recv_mgmt(ni, m, subtype, rxs, rssi, nf);
659 		goto out;
660 
661 	case IEEE80211_FC0_TYPE_CTL:
662 		vap->iv_stats.is_rx_ctl++;
663 		IEEE80211_NODE_STAT(ni, rx_ctrl);
664 		vap->iv_recv_ctl(ni, m, subtype);
665 		goto out;
666 
667 	default:
668 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
669 		    wh, "bad", "frame type 0x%x", type);
670 		/* should not come here */
671 		break;
672 	}
673 err:
674 	if_inc_counter(ifp, IFCOUNTER_IERRORS, 1);
675 out:
676 	if (m != NULL) {
677 		if (need_tap && ieee80211_radiotap_active_vap(vap))
678 			ieee80211_radiotap_rx(vap, m);
679 		m_freem(m);
680 	}
681 	return type;
682 }
683 
684 static int
is11bclient(const uint8_t * rates,const uint8_t * xrates)685 is11bclient(const uint8_t *rates, const uint8_t *xrates)
686 {
687 	static const uint32_t brates = (1<<2*1)|(1<<2*2)|(1<<11)|(1<<2*11);
688 	int i;
689 
690 	/* NB: the 11b clients we care about will not have xrates */
691 	if (xrates != NULL || rates == NULL)
692 		return 0;
693 	for (i = 0; i < rates[1]; i++) {
694 		int r = rates[2+i] & IEEE80211_RATE_VAL;
695 		if (r > 2*11 || ((1<<r) & brates) == 0)
696 			return 0;
697 	}
698 	return 1;
699 }
700 
701 static void
adhoc_recv_mgmt(struct ieee80211_node * ni,struct mbuf * m0,int subtype,const struct ieee80211_rx_stats * rxs,int rssi,int nf)702 adhoc_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
703 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
704 {
705 	struct ieee80211vap *vap = ni->ni_vap;
706 	struct ieee80211com *ic = ni->ni_ic;
707 	struct ieee80211_channel *rxchan = ic->ic_curchan;
708 	struct ieee80211_frame *wh;
709 	uint8_t *frm, *efrm;
710 	uint8_t *ssid, *rates, *xrates;
711 #if 0
712 	int ht_state_change = 0;
713 #endif
714 
715 	wh = mtod(m0, struct ieee80211_frame *);
716 	frm = (uint8_t *)&wh[1];
717 	efrm = mtod(m0, uint8_t *) + m0->m_len;
718 
719 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
720 	    "%s: recv mgmt frame, addr2=%6D, ni=%p (%6D) fc=%.02x %.02x\n",
721 	    __func__,
722 	    wh->i_addr2, ":",
723 	    ni,
724 	    ni->ni_macaddr, ":",
725 	    wh->i_fc[0],
726 	    wh->i_fc[1]);
727 	switch (subtype) {
728 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
729 	case IEEE80211_FC0_SUBTYPE_BEACON: {
730 		struct ieee80211_scanparams scan;
731 		struct ieee80211_channel *c;
732 		/*
733 		 * We process beacon/probe response
734 		 * frames to discover neighbors.
735 		 */
736 		if (rxs != NULL) {
737 			c = ieee80211_lookup_channel_rxstatus(vap, rxs);
738 			if (c != NULL)
739 				rxchan = c;
740 		}
741 		if (ieee80211_parse_beacon(ni, m0, rxchan, &scan) != 0)
742 			return;
743 		/*
744 		 * Count frame now that we know it's to be processed.
745 		 */
746 		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON) {
747 			vap->iv_stats.is_rx_beacon++;		/* XXX remove */
748 			IEEE80211_NODE_STAT(ni, rx_beacons);
749 		} else
750 			IEEE80211_NODE_STAT(ni, rx_proberesp);
751 		/*
752 		 * If scanning, just pass information to the scan module.
753 		 */
754 		if (ic->ic_flags & IEEE80211_F_SCAN) {
755 			if (ic->ic_flags_ext & IEEE80211_FEXT_PROBECHAN) {
756 				/*
757 				 * Actively scanning a channel marked passive;
758 				 * send a probe request now that we know there
759 				 * is 802.11 traffic present.
760 				 *
761 				 * XXX check if the beacon we recv'd gives
762 				 * us what we need and suppress the probe req
763 				 */
764 				ieee80211_probe_curchan(vap, true);
765 				ic->ic_flags_ext &= ~IEEE80211_FEXT_PROBECHAN;
766 			}
767 			ieee80211_add_scan(vap, rxchan, &scan, wh,
768 			    subtype, rssi, nf);
769 			return;
770 		}
771 		if (scan.capinfo & IEEE80211_CAPINFO_IBSS) {
772 			if (!IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
773 				/*
774 				 * Create a new entry in the neighbor table.
775 				 *
776 				 * XXX TODO:
777 				 *
778 				 * Here we're not scanning; so if we have an
779 				 * SSID then make sure it matches our SSID.
780 				 * Otherwise this code will match on all IBSS
781 				 * beacons/probe requests for all SSIDs,
782 				 * filling the node table with nodes that
783 				 * aren't ours.
784 				 */
785 				if (ieee80211_ibss_node_check_new(ni, &scan)) {
786 					ni = ieee80211_add_neighbor(vap, wh, &scan);
787 					/*
788 					 * Send a probe request so we announce 11n
789 					 * capabilities.
790 					 */
791 					ieee80211_send_probereq(ni, /* node */
792 					    vap->iv_myaddr, /* SA */
793 					    ni->ni_macaddr, /* DA */
794 					    vap->iv_bss->ni_bssid, /* BSSID */
795 					    vap->iv_bss->ni_essid,
796 					    vap->iv_bss->ni_esslen); /* SSID */
797 				} else
798 					ni = NULL;
799 
800 				/*
801 				 * Send a probe request so we announce 11n
802 				 * capabilities.
803 				 *
804 				 * Don't do this if we're scanning.
805 				 */
806 				if (! (ic->ic_flags & IEEE80211_F_SCAN))
807 					ieee80211_send_probereq(ni, /* node */
808 						vap->iv_myaddr, /* SA */
809 						ni->ni_macaddr, /* DA */
810 						vap->iv_bss->ni_bssid, /* BSSID */
811 						vap->iv_bss->ni_essid,
812 						vap->iv_bss->ni_esslen); /* SSID */
813 
814 			} else if (ni->ni_capinfo == 0) {
815 				/*
816 				 * Update faked node created on transmit.
817 				 * Note this also updates the tsf.
818 				 */
819 				ieee80211_init_neighbor(ni, wh, &scan);
820 
821 				/*
822 				 * Send a probe request so we announce 11n
823 				 * capabilities.
824 				 */
825 				ieee80211_send_probereq(ni, /* node */
826 					vap->iv_myaddr, /* SA */
827 					ni->ni_macaddr, /* DA */
828 					vap->iv_bss->ni_bssid, /* BSSID */
829 					vap->iv_bss->ni_essid,
830 					vap->iv_bss->ni_esslen); /* SSID */
831 			} else {
832 				/*
833 				 * Record tsf for potential resync.
834 				 */
835 				memcpy(ni->ni_tstamp.data, scan.tstamp,
836 					sizeof(ni->ni_tstamp));
837 			}
838 			/*
839 			 * This isn't enabled yet - otherwise it would
840 			 * update the HT parameters and channel width
841 			 * from any node, which could lead to lots of
842 			 * strange behaviour if the 11n nodes aren't
843 			 * exactly configured to match.
844 			 */
845 #if 0
846 			if (scan.htcap != NULL && scan.htinfo != NULL &&
847 			    (vap->iv_flags_ht & IEEE80211_FHT_HT)) {
848 				ieee80211_ht_updateparams(ni,
849 				    scan.htcap, scan.htinfo));
850 				if (ieee80211_ht_updateparams_final(ni,
851 				    scan.htcap, scan.htinfo))
852 					ht_state_change = 1;
853 			}
854 
855 			/* XXX same for VHT? */
856 #endif
857 			if (ni != NULL) {
858 				IEEE80211_RSSI_LPF(ni->ni_avgrssi, rssi);
859 				ni->ni_noise = nf;
860 			}
861 			/*
862 			 * Same here - the channel width change should
863 			 * be applied to the specific peer node, not
864 			 * to the ic.  Ie, the interface configuration
865 			 * should stay in its current channel width;
866 			 * but it should change the rate control and
867 			 * any queued frames for the given node only.
868 			 *
869 			 * Since there's no (current) way to inform
870 			 * the driver that a channel width change has
871 			 * occurred for a single node, just stub this
872 			 * out.
873 			 */
874 #if 0
875 			if (ht_state_change)
876 				ieee80211_update_chw(ic);
877 #endif
878 		}
879 		break;
880 	}
881 
882 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
883 		if (vap->iv_state != IEEE80211_S_RUN) {
884 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
885 			    wh, NULL, "wrong state %s",
886 			    ieee80211_state_name[vap->iv_state]);
887 			vap->iv_stats.is_rx_mgtdiscard++;
888 			return;
889 		}
890 		if (IEEE80211_IS_MULTICAST(wh->i_addr2)) {
891 			/* frame must be directed */
892 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
893 			    wh, NULL, "%s", "not unicast");
894 			vap->iv_stats.is_rx_mgtdiscard++;	/* XXX stat */
895 			return;
896 		}
897 
898 		/*
899 		 * prreq frame format
900 		 *	[tlv] ssid
901 		 *	[tlv] supported rates
902 		 *	[tlv] extended supported rates
903 		 */
904 		ssid = rates = xrates = NULL;
905 		while (efrm - frm > 1) {
906 			IEEE80211_VERIFY_LENGTH(efrm - frm, frm[1] + 2, return);
907 			switch (*frm) {
908 			case IEEE80211_ELEMID_SSID:
909 				ssid = frm;
910 				break;
911 			case IEEE80211_ELEMID_RATES:
912 				rates = frm;
913 				break;
914 			case IEEE80211_ELEMID_XRATES:
915 				xrates = frm;
916 				break;
917 			}
918 			frm += frm[1] + 2;
919 		}
920 		IEEE80211_VERIFY_ELEMENT(rates, IEEE80211_RATE_MAXSIZE, return);
921 		if (xrates != NULL)
922 			IEEE80211_VERIFY_ELEMENT(xrates,
923 				IEEE80211_RATE_MAXSIZE - rates[1], return);
924 		IEEE80211_VERIFY_ELEMENT(ssid, IEEE80211_NWID_LEN, return);
925 		IEEE80211_VERIFY_SSID(vap->iv_bss, ssid, return);
926 		if ((vap->iv_flags & IEEE80211_F_HIDESSID) && ssid[1] == 0) {
927 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
928 			    wh, NULL,
929 			    "%s", "no ssid with ssid suppression enabled");
930 			vap->iv_stats.is_rx_ssidmismatch++; /*XXX*/
931 			return;
932 		}
933 
934 		/* XXX find a better class or define it's own */
935 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_INPUT, wh->i_addr2,
936 		    "%s", "recv probe req");
937 		/*
938 		 * Some legacy 11b clients cannot hack a complete
939 		 * probe response frame.  When the request includes
940 		 * only a bare-bones rate set, communicate this to
941 		 * the transmit side.
942 		 */
943 		ieee80211_send_proberesp(vap, wh->i_addr2,
944 		    is11bclient(rates, xrates) ? IEEE80211_SEND_LEGACY_11B : 0);
945 
946 		/*
947 		 * Note: we don't benefit from stashing the probe request
948 		 * IEs away to use for IBSS negotiation, because we
949 		 * typically don't get all of the IEs.
950 		 */
951 		break;
952 
953 	case IEEE80211_FC0_SUBTYPE_ACTION:
954 	case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
955 		if ((ni == vap->iv_bss) &&
956 		    !IEEE80211_ADDR_EQ(wh->i_addr2, ni->ni_macaddr)) {
957 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
958 			    wh, NULL, "%s", "unknown node");
959 			vap->iv_stats.is_rx_mgtdiscard++;
960 		} else if (!IEEE80211_ADDR_EQ(vap->iv_myaddr, wh->i_addr1) &&
961 		    !IEEE80211_IS_MULTICAST(wh->i_addr1)) {
962 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
963 			    wh, NULL, "%s", "not for us");
964 			vap->iv_stats.is_rx_mgtdiscard++;
965 		} else if (vap->iv_state != IEEE80211_S_RUN) {
966 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT | IEEE80211_MSG_DEBUG,
967 			    wh, NULL, "wrong state %s",
968 			    ieee80211_state_name[vap->iv_state]);
969 			vap->iv_stats.is_rx_mgtdiscard++;
970 		} else {
971 			if (ieee80211_parse_action(ni, m0) == 0)
972 				(void)ic->ic_recv_action(ni, wh, frm, efrm);
973 		}
974 		break;
975 
976 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
977 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
978 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
979 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
980 	case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
981 	case IEEE80211_FC0_SUBTYPE_ATIM:
982 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
983 	case IEEE80211_FC0_SUBTYPE_AUTH:
984 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
985 		IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
986 		    wh, NULL, "%s", "not handled");
987 		vap->iv_stats.is_rx_mgtdiscard++;
988 		break;
989 
990 	default:
991 		IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
992 		    wh, "mgt", "subtype 0x%x not handled", subtype);
993 		vap->iv_stats.is_rx_badsubtype++;
994 		break;
995 	}
996 }
997 #undef IEEE80211_VERIFY_LENGTH
998 #undef IEEE80211_VERIFY_ELEMENT
999 
1000 static void
ahdemo_recv_mgmt(struct ieee80211_node * ni,struct mbuf * m0,int subtype,const struct ieee80211_rx_stats * rxs,int rssi,int nf)1001 ahdemo_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m0,
1002 	int subtype, const struct ieee80211_rx_stats *rxs, int rssi, int nf)
1003 {
1004 	struct ieee80211vap *vap = ni->ni_vap;
1005 	struct ieee80211com *ic = ni->ni_ic;
1006 
1007 	/*
1008 	 * Process management frames when scanning; useful for doing
1009 	 * a site-survey.
1010 	 */
1011 	if (ic->ic_flags & IEEE80211_F_SCAN)
1012 		adhoc_recv_mgmt(ni, m0, subtype, rxs, rssi, nf);
1013 	else {
1014 #ifdef IEEE80211_DEBUG
1015 		struct ieee80211_frame *wh;
1016 
1017 		wh = mtod(m0, struct ieee80211_frame *);
1018 #endif
1019 		switch (subtype) {
1020 		case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1021 		case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1022 		case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1023 		case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1024 		case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
1025 		case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1026 		case IEEE80211_FC0_SUBTYPE_TIMING_ADV:
1027 		case IEEE80211_FC0_SUBTYPE_BEACON:
1028 		case IEEE80211_FC0_SUBTYPE_ATIM:
1029 		case IEEE80211_FC0_SUBTYPE_DISASSOC:
1030 		case IEEE80211_FC0_SUBTYPE_AUTH:
1031 		case IEEE80211_FC0_SUBTYPE_DEAUTH:
1032 		case IEEE80211_FC0_SUBTYPE_ACTION:
1033 		case IEEE80211_FC0_SUBTYPE_ACTION_NOACK:
1034 			IEEE80211_DISCARD(vap, IEEE80211_MSG_INPUT,
1035 			     wh, NULL, "%s", "not handled");
1036 			vap->iv_stats.is_rx_mgtdiscard++;
1037 			break;
1038 		default:
1039 			IEEE80211_DISCARD(vap, IEEE80211_MSG_ANY,
1040 			     wh, "mgt", "subtype 0x%x not handled", subtype);
1041 			vap->iv_stats.is_rx_badsubtype++;
1042 			break;
1043 		}
1044 	}
1045 }
1046 
1047 static void
adhoc_recv_ctl(struct ieee80211_node * ni,struct mbuf * m,int subtype)1048 adhoc_recv_ctl(struct ieee80211_node *ni, struct mbuf *m, int subtype)
1049 {
1050 
1051 	switch (subtype) {
1052 	case IEEE80211_FC0_SUBTYPE_BAR:
1053 		ieee80211_recv_bar(ni, m);
1054 		break;
1055 	}
1056 }
1057