xref: /freebsd/sys/net80211/ieee80211_output.c (revision 3157ba21)
1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_inet.h"
31 #include "opt_inet6.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/kernel.h>
38 #include <sys/endian.h>
39 
40 #include <sys/socket.h>
41 
42 #include <net/bpf.h>
43 #include <net/ethernet.h>
44 #include <net/if.h>
45 #include <net/if_llc.h>
46 #include <net/if_media.h>
47 #include <net/if_vlan_var.h>
48 
49 #include <net80211/ieee80211_var.h>
50 #include <net80211/ieee80211_regdomain.h>
51 #ifdef IEEE80211_SUPPORT_SUPERG
52 #include <net80211/ieee80211_superg.h>
53 #endif
54 #ifdef IEEE80211_SUPPORT_TDMA
55 #include <net80211/ieee80211_tdma.h>
56 #endif
57 #include <net80211/ieee80211_wds.h>
58 #include <net80211/ieee80211_mesh.h>
59 
60 #ifdef INET
61 #include <netinet/in.h>
62 #include <netinet/if_ether.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #endif
66 #ifdef INET6
67 #include <netinet/ip6.h>
68 #endif
69 
70 #include <security/mac/mac_framework.h>
71 
72 #define	ETHER_HEADER_COPY(dst, src) \
73 	memcpy(dst, src, sizeof(struct ether_header))
74 
75 /* unalligned little endian access */
76 #define LE_WRITE_2(p, v) do {				\
77 	((uint8_t *)(p))[0] = (v) & 0xff;		\
78 	((uint8_t *)(p))[1] = ((v) >> 8) & 0xff;	\
79 } while (0)
80 #define LE_WRITE_4(p, v) do {				\
81 	((uint8_t *)(p))[0] = (v) & 0xff;		\
82 	((uint8_t *)(p))[1] = ((v) >> 8) & 0xff;	\
83 	((uint8_t *)(p))[2] = ((v) >> 16) & 0xff;	\
84 	((uint8_t *)(p))[3] = ((v) >> 24) & 0xff;	\
85 } while (0)
86 
87 static int ieee80211_fragment(struct ieee80211vap *, struct mbuf *,
88 	u_int hdrsize, u_int ciphdrsize, u_int mtu);
89 static	void ieee80211_tx_mgt_cb(struct ieee80211_node *, void *, int);
90 
91 #ifdef IEEE80211_DEBUG
92 /*
93  * Decide if an outbound management frame should be
94  * printed when debugging is enabled.  This filters some
95  * of the less interesting frames that come frequently
96  * (e.g. beacons).
97  */
98 static __inline int
99 doprint(struct ieee80211vap *vap, int subtype)
100 {
101 	switch (subtype) {
102 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
103 		return (vap->iv_opmode == IEEE80211_M_IBSS);
104 	}
105 	return 1;
106 }
107 #endif
108 
109 /*
110  * Start method for vap's.  All packets from the stack come
111  * through here.  We handle common processing of the packets
112  * before dispatching them to the underlying device.
113  */
114 void
115 ieee80211_start(struct ifnet *ifp)
116 {
117 #define	IS_DWDS(vap) \
118 	(vap->iv_opmode == IEEE80211_M_WDS && \
119 	 (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0)
120 	struct ieee80211vap *vap = ifp->if_softc;
121 	struct ieee80211com *ic = vap->iv_ic;
122 	struct ifnet *parent = ic->ic_ifp;
123 	struct ieee80211_node *ni;
124 	struct mbuf *m;
125 	struct ether_header *eh;
126 	int error;
127 
128 	/* NB: parent must be up and running */
129 	if (!IFNET_IS_UP_RUNNING(parent)) {
130 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
131 		    "%s: ignore queue, parent %s not up+running\n",
132 		    __func__, parent->if_xname);
133 		/* XXX stat */
134 		return;
135 	}
136 	if (vap->iv_state == IEEE80211_S_SLEEP) {
137 		/*
138 		 * In power save, wakeup device for transmit.
139 		 */
140 		ieee80211_new_state(vap, IEEE80211_S_RUN, 0);
141 		return;
142 	}
143 	/*
144 	 * No data frames go out unless we're running.
145 	 * Note in particular this covers CAC and CSA
146 	 * states (though maybe we should check muting
147 	 * for CSA).
148 	 */
149 	if (vap->iv_state != IEEE80211_S_RUN) {
150 		IEEE80211_LOCK(ic);
151 		/* re-check under the com lock to avoid races */
152 		if (vap->iv_state != IEEE80211_S_RUN) {
153 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
154 			    "%s: ignore queue, in %s state\n",
155 			    __func__, ieee80211_state_name[vap->iv_state]);
156 			vap->iv_stats.is_tx_badstate++;
157 			ifp->if_drv_flags |= IFF_DRV_OACTIVE;
158 			IEEE80211_UNLOCK(ic);
159 			return;
160 		}
161 		IEEE80211_UNLOCK(ic);
162 	}
163 	for (;;) {
164 		IFQ_DEQUEUE(&ifp->if_snd, m);
165 		if (m == NULL)
166 			break;
167 		/*
168 		 * Sanitize mbuf flags for net80211 use.  We cannot
169 		 * clear M_PWR_SAV or M_MORE_DATA because these may
170 		 * be set for frames that are re-submitted from the
171 		 * power save queue.
172 		 *
173 		 * NB: This must be done before ieee80211_classify as
174 		 *     it marks EAPOL in frames with M_EAPOL.
175 		 */
176 		m->m_flags &= ~(M_80211_TX - M_PWR_SAV - M_MORE_DATA);
177 		/*
178 		 * Cancel any background scan.
179 		 */
180 		if (ic->ic_flags & IEEE80211_F_SCAN)
181 			ieee80211_cancel_anyscan(vap);
182 		/*
183 		 * Find the node for the destination so we can do
184 		 * things like power save and fast frames aggregation.
185 		 *
186 		 * NB: past this point various code assumes the first
187 		 *     mbuf has the 802.3 header present (and contiguous).
188 		 */
189 		ni = NULL;
190 		if (m->m_len < sizeof(struct ether_header) &&
191 		   (m = m_pullup(m, sizeof(struct ether_header))) == NULL) {
192 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
193 			    "discard frame, %s\n", "m_pullup failed");
194 			vap->iv_stats.is_tx_nobuf++;	/* XXX */
195 			ifp->if_oerrors++;
196 			continue;
197 		}
198 		eh = mtod(m, struct ether_header *);
199 		if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
200 			if (IS_DWDS(vap)) {
201 				/*
202 				 * Only unicast frames from the above go out
203 				 * DWDS vaps; multicast frames are handled by
204 				 * dispatching the frame as it comes through
205 				 * the AP vap (see below).
206 				 */
207 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_WDS,
208 				    eh->ether_dhost, "mcast", "%s", "on DWDS");
209 				vap->iv_stats.is_dwds_mcast++;
210 				m_freem(m);
211 				continue;
212 			}
213 			if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
214 				/*
215 				 * Spam DWDS vap's w/ multicast traffic.
216 				 */
217 				/* XXX only if dwds in use? */
218 				ieee80211_dwds_mcast(vap, m);
219 			}
220 		}
221 #ifdef IEEE80211_SUPPORT_MESH
222 		if (vap->iv_opmode != IEEE80211_M_MBSS) {
223 #endif
224 			ni = ieee80211_find_txnode(vap, eh->ether_dhost);
225 			if (ni == NULL) {
226 				/* NB: ieee80211_find_txnode does stat+msg */
227 				ifp->if_oerrors++;
228 				m_freem(m);
229 				continue;
230 			}
231 			if (ni->ni_associd == 0 &&
232 			    (ni->ni_flags & IEEE80211_NODE_ASSOCID)) {
233 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
234 				    eh->ether_dhost, NULL,
235 				    "sta not associated (type 0x%04x)",
236 				    htons(eh->ether_type));
237 				vap->iv_stats.is_tx_notassoc++;
238 				ifp->if_oerrors++;
239 				m_freem(m);
240 				ieee80211_free_node(ni);
241 				continue;
242 			}
243 #ifdef IEEE80211_SUPPORT_MESH
244 		} else {
245 			if (!IEEE80211_ADDR_EQ(eh->ether_shost, vap->iv_myaddr)) {
246 				/*
247 				 * Proxy station only if configured.
248 				 */
249 				if (!ieee80211_mesh_isproxyena(vap)) {
250 					IEEE80211_DISCARD_MAC(vap,
251 					    IEEE80211_MSG_OUTPUT |
252 						IEEE80211_MSG_MESH,
253 					    eh->ether_dhost, NULL,
254 					    "%s", "proxy not enabled");
255 					vap->iv_stats.is_mesh_notproxy++;
256 					ifp->if_oerrors++;
257 					m_freem(m);
258 					continue;
259 				}
260 				ieee80211_mesh_proxy_check(vap, eh->ether_shost);
261 			}
262 			ni = ieee80211_mesh_discover(vap, eh->ether_dhost, m);
263 			if (ni == NULL) {
264 				/*
265 				 * NB: ieee80211_mesh_discover holds/disposes
266 				 * frame (e.g. queueing on path discovery).
267 				 */
268 				ifp->if_oerrors++;
269 				continue;
270 			}
271 		}
272 #endif
273 		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
274 		    (m->m_flags & M_PWR_SAV) == 0) {
275 			/*
276 			 * Station in power save mode; pass the frame
277 			 * to the 802.11 layer and continue.  We'll get
278 			 * the frame back when the time is right.
279 			 * XXX lose WDS vap linkage?
280 			 */
281 			(void) ieee80211_pwrsave(ni, m);
282 			ieee80211_free_node(ni);
283 			continue;
284 		}
285 		/* calculate priority so drivers can find the tx queue */
286 		if (ieee80211_classify(ni, m)) {
287 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
288 			    eh->ether_dhost, NULL,
289 			    "%s", "classification failure");
290 			vap->iv_stats.is_tx_classify++;
291 			ifp->if_oerrors++;
292 			m_freem(m);
293 			ieee80211_free_node(ni);
294 			continue;
295 		}
296 		/*
297 		 * Stash the node pointer.  Note that we do this after
298 		 * any call to ieee80211_dwds_mcast because that code
299 		 * uses any existing value for rcvif to identify the
300 		 * interface it (might have been) received on.
301 		 */
302 		m->m_pkthdr.rcvif = (void *)ni;
303 
304 		BPF_MTAP(ifp, m);		/* 802.3 tx */
305 
306 		/*
307 		 * Check if A-MPDU tx aggregation is setup or if we
308 		 * should try to enable it.  The sta must be associated
309 		 * with HT and A-MPDU enabled for use.  When the policy
310 		 * routine decides we should enable A-MPDU we issue an
311 		 * ADDBA request and wait for a reply.  The frame being
312 		 * encapsulated will go out w/o using A-MPDU, or possibly
313 		 * it might be collected by the driver and held/retransmit.
314 		 * The default ic_ampdu_enable routine handles staggering
315 		 * ADDBA requests in case the receiver NAK's us or we are
316 		 * otherwise unable to establish a BA stream.
317 		 */
318 		if ((ni->ni_flags & IEEE80211_NODE_AMPDU_TX) &&
319 		    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_TX) &&
320 		    (m->m_flags & M_EAPOL) == 0) {
321 			const int ac = M_WME_GETAC(m);
322 			struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[ac];
323 
324 			ieee80211_txampdu_count_packet(tap);
325 			if (IEEE80211_AMPDU_RUNNING(tap)) {
326 				/*
327 				 * Operational, mark frame for aggregation.
328 				 *
329 				 * XXX do tx aggregation here
330 				 */
331 				m->m_flags |= M_AMPDU_MPDU;
332 			} else if (!IEEE80211_AMPDU_REQUESTED(tap) &&
333 			    ic->ic_ampdu_enable(ni, tap)) {
334 				/*
335 				 * Not negotiated yet, request service.
336 				 */
337 				ieee80211_ampdu_request(ni, tap);
338 				/* XXX hold frame for reply? */
339 			}
340 		}
341 #ifdef IEEE80211_SUPPORT_SUPERG
342 		else if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_NODE_FF)) {
343 			m = ieee80211_ff_check(ni, m);
344 			if (m == NULL) {
345 				/* NB: any ni ref held on stageq */
346 				continue;
347 			}
348 		}
349 #endif /* IEEE80211_SUPPORT_SUPERG */
350 		if (__predict_true((vap->iv_caps & IEEE80211_C_8023ENCAP) == 0)) {
351 			/*
352 			 * Encapsulate the packet in prep for transmission.
353 			 */
354 			m = ieee80211_encap(vap, ni, m);
355 			if (m == NULL) {
356 				/* NB: stat+msg handled in ieee80211_encap */
357 				ieee80211_free_node(ni);
358 				continue;
359 			}
360 		}
361 
362 		error = parent->if_transmit(parent, m);
363 		if (error != 0) {
364 			/* NB: IFQ_HANDOFF reclaims mbuf */
365 			ieee80211_free_node(ni);
366 		} else {
367 			ifp->if_opackets++;
368 		}
369 		ic->ic_lastdata = ticks;
370 	}
371 #undef IS_DWDS
372 }
373 
374 /*
375  * 802.11 output routine. This is (currently) used only to
376  * connect bpf write calls to the 802.11 layer for injecting
377  * raw 802.11 frames.
378  */
379 int
380 ieee80211_output(struct ifnet *ifp, struct mbuf *m,
381 	struct sockaddr *dst, struct route *ro)
382 {
383 #define senderr(e) do { error = (e); goto bad;} while (0)
384 	struct ieee80211_node *ni = NULL;
385 	struct ieee80211vap *vap;
386 	struct ieee80211_frame *wh;
387 	int error;
388 
389 	if (ifp->if_drv_flags & IFF_DRV_OACTIVE) {
390 		/*
391 		 * Short-circuit requests if the vap is marked OACTIVE
392 		 * as this can happen because a packet came down through
393 		 * ieee80211_start before the vap entered RUN state in
394 		 * which case it's ok to just drop the frame.  This
395 		 * should not be necessary but callers of if_output don't
396 		 * check OACTIVE.
397 		 */
398 		senderr(ENETDOWN);
399 	}
400 	vap = ifp->if_softc;
401 	/*
402 	 * Hand to the 802.3 code if not tagged as
403 	 * a raw 802.11 frame.
404 	 */
405 	if (dst->sa_family != AF_IEEE80211)
406 		return vap->iv_output(ifp, m, dst, ro);
407 #ifdef MAC
408 	error = mac_ifnet_check_transmit(ifp, m);
409 	if (error)
410 		senderr(error);
411 #endif
412 	if (ifp->if_flags & IFF_MONITOR)
413 		senderr(ENETDOWN);
414 	if (!IFNET_IS_UP_RUNNING(ifp))
415 		senderr(ENETDOWN);
416 	if (vap->iv_state == IEEE80211_S_CAC) {
417 		IEEE80211_DPRINTF(vap,
418 		    IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
419 		    "block %s frame in CAC state\n", "raw data");
420 		vap->iv_stats.is_tx_badstate++;
421 		senderr(EIO);		/* XXX */
422 	}
423 	/* XXX bypass bridge, pfil, carp, etc. */
424 
425 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_ack))
426 		senderr(EIO);	/* XXX */
427 	wh = mtod(m, struct ieee80211_frame *);
428 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
429 	    IEEE80211_FC0_VERSION_0)
430 		senderr(EIO);	/* XXX */
431 
432 	/* locate destination node */
433 	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
434 	case IEEE80211_FC1_DIR_NODS:
435 	case IEEE80211_FC1_DIR_FROMDS:
436 		ni = ieee80211_find_txnode(vap, wh->i_addr1);
437 		break;
438 	case IEEE80211_FC1_DIR_TODS:
439 	case IEEE80211_FC1_DIR_DSTODS:
440 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame))
441 			senderr(EIO);	/* XXX */
442 		ni = ieee80211_find_txnode(vap, wh->i_addr3);
443 		break;
444 	default:
445 		senderr(EIO);	/* XXX */
446 	}
447 	if (ni == NULL) {
448 		/*
449 		 * Permit packets w/ bpf params through regardless
450 		 * (see below about sa_len).
451 		 */
452 		if (dst->sa_len == 0)
453 			senderr(EHOSTUNREACH);
454 		ni = ieee80211_ref_node(vap->iv_bss);
455 	}
456 
457 	/*
458 	 * Sanitize mbuf for net80211 flags leaked from above.
459 	 *
460 	 * NB: This must be done before ieee80211_classify as
461 	 *     it marks EAPOL in frames with M_EAPOL.
462 	 */
463 	m->m_flags &= ~M_80211_TX;
464 
465 	/* calculate priority so drivers can find the tx queue */
466 	/* XXX assumes an 802.3 frame */
467 	if (ieee80211_classify(ni, m))
468 		senderr(EIO);		/* XXX */
469 
470 	ifp->if_opackets++;
471 	IEEE80211_NODE_STAT(ni, tx_data);
472 	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
473 		IEEE80211_NODE_STAT(ni, tx_mcast);
474 		m->m_flags |= M_MCAST;
475 	} else
476 		IEEE80211_NODE_STAT(ni, tx_ucast);
477 	/* NB: ieee80211_encap does not include 802.11 header */
478 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, m->m_pkthdr.len);
479 
480 	/*
481 	 * NB: DLT_IEEE802_11_RADIO identifies the parameters are
482 	 * present by setting the sa_len field of the sockaddr (yes,
483 	 * this is a hack).
484 	 * NB: we assume sa_data is suitably aligned to cast.
485 	 */
486 	return vap->iv_ic->ic_raw_xmit(ni, m,
487 	    (const struct ieee80211_bpf_params *)(dst->sa_len ?
488 		dst->sa_data : NULL));
489 bad:
490 	if (m != NULL)
491 		m_freem(m);
492 	if (ni != NULL)
493 		ieee80211_free_node(ni);
494 	ifp->if_oerrors++;
495 	return error;
496 #undef senderr
497 }
498 
499 /*
500  * Set the direction field and address fields of an outgoing
501  * frame.  Note this should be called early on in constructing
502  * a frame as it sets i_fc[1]; other bits can then be or'd in.
503  */
504 void
505 ieee80211_send_setup(
506 	struct ieee80211_node *ni,
507 	struct mbuf *m,
508 	int type, int tid,
509 	const uint8_t sa[IEEE80211_ADDR_LEN],
510 	const uint8_t da[IEEE80211_ADDR_LEN],
511 	const uint8_t bssid[IEEE80211_ADDR_LEN])
512 {
513 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
514 	struct ieee80211vap *vap = ni->ni_vap;
515 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
516 	ieee80211_seq seqno;
517 
518 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
519 	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
520 		switch (vap->iv_opmode) {
521 		case IEEE80211_M_STA:
522 			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
523 			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
524 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
525 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
526 			break;
527 		case IEEE80211_M_IBSS:
528 		case IEEE80211_M_AHDEMO:
529 			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
530 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
531 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
532 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
533 			break;
534 		case IEEE80211_M_HOSTAP:
535 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
536 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
537 			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
538 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
539 			break;
540 		case IEEE80211_M_WDS:
541 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
542 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
543 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
544 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
545 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
546 			break;
547 		case IEEE80211_M_MBSS:
548 #ifdef IEEE80211_SUPPORT_MESH
549 			/* XXX add support for proxied addresses */
550 			if (IEEE80211_IS_MULTICAST(da)) {
551 				wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
552 				/* XXX next hop */
553 				IEEE80211_ADDR_COPY(wh->i_addr1, da);
554 				IEEE80211_ADDR_COPY(wh->i_addr2,
555 				    vap->iv_myaddr);
556 			} else {
557 				wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
558 				IEEE80211_ADDR_COPY(wh->i_addr1, da);
559 				IEEE80211_ADDR_COPY(wh->i_addr2,
560 				    vap->iv_myaddr);
561 				IEEE80211_ADDR_COPY(wh->i_addr3, da);
562 				IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
563 			}
564 #endif
565 			break;
566 		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
567 			break;
568 		}
569 	} else {
570 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
571 		IEEE80211_ADDR_COPY(wh->i_addr1, da);
572 		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
573 #ifdef IEEE80211_SUPPORT_MESH
574 		if (vap->iv_opmode == IEEE80211_M_MBSS)
575 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
576 		else
577 #endif
578 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
579 	}
580 	*(uint16_t *)&wh->i_dur[0] = 0;
581 
582 	seqno = ni->ni_txseqs[tid]++;
583 	*(uint16_t *)&wh->i_seq[0] = htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
584 	M_SEQNO_SET(m, seqno);
585 
586 	if (IEEE80211_IS_MULTICAST(wh->i_addr1))
587 		m->m_flags |= M_MCAST;
588 #undef WH4
589 }
590 
591 /*
592  * Send a management frame to the specified node.  The node pointer
593  * must have a reference as the pointer will be passed to the driver
594  * and potentially held for a long time.  If the frame is successfully
595  * dispatched to the driver, then it is responsible for freeing the
596  * reference (and potentially free'ing up any associated storage);
597  * otherwise deal with reclaiming any reference (on error).
598  */
599 int
600 ieee80211_mgmt_output(struct ieee80211_node *ni, struct mbuf *m, int type,
601 	struct ieee80211_bpf_params *params)
602 {
603 	struct ieee80211vap *vap = ni->ni_vap;
604 	struct ieee80211com *ic = ni->ni_ic;
605 	struct ieee80211_frame *wh;
606 
607 	KASSERT(ni != NULL, ("null node"));
608 
609 	if (vap->iv_state == IEEE80211_S_CAC) {
610 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
611 		    ni, "block %s frame in CAC state",
612 			ieee80211_mgt_subtype_name[
613 			    (type & IEEE80211_FC0_SUBTYPE_MASK) >>
614 				IEEE80211_FC0_SUBTYPE_SHIFT]);
615 		vap->iv_stats.is_tx_badstate++;
616 		ieee80211_free_node(ni);
617 		m_freem(m);
618 		return EIO;		/* XXX */
619 	}
620 
621 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
622 	if (m == NULL) {
623 		ieee80211_free_node(ni);
624 		return ENOMEM;
625 	}
626 
627 	wh = mtod(m, struct ieee80211_frame *);
628 	ieee80211_send_setup(ni, m,
629 	     IEEE80211_FC0_TYPE_MGT | type, IEEE80211_NONQOS_TID,
630 	     vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
631 	if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
632 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_AUTH, wh->i_addr1,
633 		    "encrypting frame (%s)", __func__);
634 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
635 	}
636 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
637 
638 	KASSERT(type != IEEE80211_FC0_SUBTYPE_PROBE_RESP, ("probe response?"));
639 	M_WME_SETAC(m, params->ibp_pri);
640 
641 #ifdef IEEE80211_DEBUG
642 	/* avoid printing too many frames */
643 	if ((ieee80211_msg_debug(vap) && doprint(vap, type)) ||
644 	    ieee80211_msg_dumppkts(vap)) {
645 		printf("[%s] send %s on channel %u\n",
646 		    ether_sprintf(wh->i_addr1),
647 		    ieee80211_mgt_subtype_name[
648 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
649 				IEEE80211_FC0_SUBTYPE_SHIFT],
650 		    ieee80211_chan2ieee(ic, ic->ic_curchan));
651 	}
652 #endif
653 	IEEE80211_NODE_STAT(ni, tx_mgmt);
654 
655 	return ic->ic_raw_xmit(ni, m, params);
656 }
657 
658 /*
659  * Send a null data frame to the specified node.  If the station
660  * is setup for QoS then a QoS Null Data frame is constructed.
661  * If this is a WDS station then a 4-address frame is constructed.
662  *
663  * NB: the caller is assumed to have setup a node reference
664  *     for use; this is necessary to deal with a race condition
665  *     when probing for inactive stations.  Like ieee80211_mgmt_output
666  *     we must cleanup any node reference on error;  however we
667  *     can safely just unref it as we know it will never be the
668  *     last reference to the node.
669  */
670 int
671 ieee80211_send_nulldata(struct ieee80211_node *ni)
672 {
673 	struct ieee80211vap *vap = ni->ni_vap;
674 	struct ieee80211com *ic = ni->ni_ic;
675 	struct mbuf *m;
676 	struct ieee80211_frame *wh;
677 	int hdrlen;
678 	uint8_t *frm;
679 
680 	if (vap->iv_state == IEEE80211_S_CAC) {
681 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
682 		    ni, "block %s frame in CAC state", "null data");
683 		ieee80211_unref_node(&ni);
684 		vap->iv_stats.is_tx_badstate++;
685 		return EIO;		/* XXX */
686 	}
687 
688 	if (ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT))
689 		hdrlen = sizeof(struct ieee80211_qosframe);
690 	else
691 		hdrlen = sizeof(struct ieee80211_frame);
692 	/* NB: only WDS vap's get 4-address frames */
693 	if (vap->iv_opmode == IEEE80211_M_WDS)
694 		hdrlen += IEEE80211_ADDR_LEN;
695 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
696 		hdrlen = roundup(hdrlen, sizeof(uint32_t));
697 
698 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom + hdrlen, 0);
699 	if (m == NULL) {
700 		/* XXX debug msg */
701 		ieee80211_unref_node(&ni);
702 		vap->iv_stats.is_tx_nobuf++;
703 		return ENOMEM;
704 	}
705 	KASSERT(M_LEADINGSPACE(m) >= hdrlen,
706 	    ("leading space %zd", M_LEADINGSPACE(m)));
707 	M_PREPEND(m, hdrlen, M_DONTWAIT);
708 	if (m == NULL) {
709 		/* NB: cannot happen */
710 		ieee80211_free_node(ni);
711 		return ENOMEM;
712 	}
713 
714 	wh = mtod(m, struct ieee80211_frame *);		/* NB: a little lie */
715 	if (ni->ni_flags & IEEE80211_NODE_QOS) {
716 		const int tid = WME_AC_TO_TID(WME_AC_BE);
717 		uint8_t *qos;
718 
719 		ieee80211_send_setup(ni, m,
720 		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS_NULL,
721 		    tid, vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
722 
723 		if (vap->iv_opmode == IEEE80211_M_WDS)
724 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
725 		else
726 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
727 		qos[0] = tid & IEEE80211_QOS_TID;
728 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[WME_AC_BE].wmep_noackPolicy)
729 			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
730 		qos[1] = 0;
731 	} else {
732 		ieee80211_send_setup(ni, m,
733 		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
734 		    IEEE80211_NONQOS_TID,
735 		    vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
736 	}
737 	if (vap->iv_opmode != IEEE80211_M_WDS) {
738 		/* NB: power management bit is never sent by an AP */
739 		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
740 		    vap->iv_opmode != IEEE80211_M_HOSTAP)
741 			wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
742 	}
743 	m->m_len = m->m_pkthdr.len = hdrlen;
744 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
745 
746 	M_WME_SETAC(m, WME_AC_BE);
747 
748 	IEEE80211_NODE_STAT(ni, tx_data);
749 
750 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS, ni,
751 	    "send %snull data frame on channel %u, pwr mgt %s",
752 	    ni->ni_flags & IEEE80211_NODE_QOS ? "QoS " : "",
753 	    ieee80211_chan2ieee(ic, ic->ic_curchan),
754 	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");
755 
756 	return ic->ic_raw_xmit(ni, m, NULL);
757 }
758 
759 /*
760  * Assign priority to a frame based on any vlan tag assigned
761  * to the station and/or any Diffserv setting in an IP header.
762  * Finally, if an ACM policy is setup (in station mode) it's
763  * applied.
764  */
765 int
766 ieee80211_classify(struct ieee80211_node *ni, struct mbuf *m)
767 {
768 	const struct ether_header *eh = mtod(m, struct ether_header *);
769 	int v_wme_ac, d_wme_ac, ac;
770 
771 	/*
772 	 * Always promote PAE/EAPOL frames to high priority.
773 	 */
774 	if (eh->ether_type == htons(ETHERTYPE_PAE)) {
775 		/* NB: mark so others don't need to check header */
776 		m->m_flags |= M_EAPOL;
777 		ac = WME_AC_VO;
778 		goto done;
779 	}
780 	/*
781 	 * Non-qos traffic goes to BE.
782 	 */
783 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
784 		ac = WME_AC_BE;
785 		goto done;
786 	}
787 
788 	/*
789 	 * If node has a vlan tag then all traffic
790 	 * to it must have a matching tag.
791 	 */
792 	v_wme_ac = 0;
793 	if (ni->ni_vlan != 0) {
794 		 if ((m->m_flags & M_VLANTAG) == 0) {
795 			IEEE80211_NODE_STAT(ni, tx_novlantag);
796 			return 1;
797 		}
798 		if (EVL_VLANOFTAG(m->m_pkthdr.ether_vtag) !=
799 		    EVL_VLANOFTAG(ni->ni_vlan)) {
800 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
801 			return 1;
802 		}
803 		/* map vlan priority to AC */
804 		v_wme_ac = TID_TO_WME_AC(EVL_PRIOFTAG(ni->ni_vlan));
805 	}
806 
807 	/* XXX m_copydata may be too slow for fast path */
808 #ifdef INET
809 	if (eh->ether_type == htons(ETHERTYPE_IP)) {
810 		uint8_t tos;
811 		/*
812 		 * IP frame, map the DSCP bits from the TOS field.
813 		 */
814 		/* NB: ip header may not be in first mbuf */
815 		m_copydata(m, sizeof(struct ether_header) +
816 		    offsetof(struct ip, ip_tos), sizeof(tos), &tos);
817 		tos >>= 5;		/* NB: ECN + low 3 bits of DSCP */
818 		d_wme_ac = TID_TO_WME_AC(tos);
819 	} else {
820 #endif /* INET */
821 #ifdef INET6
822 	if (eh->ether_type == htons(ETHERTYPE_IPV6)) {
823 		uint32_t flow;
824 		uint8_t tos;
825 		/*
826 		 * IPv6 frame, map the DSCP bits from the TOS field.
827 		 */
828 		m_copydata(m, sizeof(struct ether_header) +
829 		    offsetof(struct ip6_hdr, ip6_flow), sizeof(flow),
830 		    (caddr_t) &flow);
831 		tos = (uint8_t)(ntohl(flow) >> 20);
832 		tos >>= 5;		/* NB: ECN + low 3 bits of DSCP */
833 		d_wme_ac = TID_TO_WME_AC(tos);
834 	} else {
835 #endif /* INET6 */
836 		d_wme_ac = WME_AC_BE;
837 #ifdef INET6
838 	}
839 #endif
840 #ifdef INET
841 	}
842 #endif
843 	/*
844 	 * Use highest priority AC.
845 	 */
846 	if (v_wme_ac > d_wme_ac)
847 		ac = v_wme_ac;
848 	else
849 		ac = d_wme_ac;
850 
851 	/*
852 	 * Apply ACM policy.
853 	 */
854 	if (ni->ni_vap->iv_opmode == IEEE80211_M_STA) {
855 		static const int acmap[4] = {
856 			WME_AC_BK,	/* WME_AC_BE */
857 			WME_AC_BK,	/* WME_AC_BK */
858 			WME_AC_BE,	/* WME_AC_VI */
859 			WME_AC_VI,	/* WME_AC_VO */
860 		};
861 		struct ieee80211com *ic = ni->ni_ic;
862 
863 		while (ac != WME_AC_BK &&
864 		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
865 			ac = acmap[ac];
866 	}
867 done:
868 	M_WME_SETAC(m, ac);
869 	return 0;
870 }
871 
872 /*
873  * Insure there is sufficient contiguous space to encapsulate the
874  * 802.11 data frame.  If room isn't already there, arrange for it.
875  * Drivers and cipher modules assume we have done the necessary work
876  * and fail rudely if they don't find the space they need.
877  */
878 struct mbuf *
879 ieee80211_mbuf_adjust(struct ieee80211vap *vap, int hdrsize,
880 	struct ieee80211_key *key, struct mbuf *m)
881 {
882 #define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
883 	int needed_space = vap->iv_ic->ic_headroom + hdrsize;
884 
885 	if (key != NULL) {
886 		/* XXX belongs in crypto code? */
887 		needed_space += key->wk_cipher->ic_header;
888 		/* XXX frags */
889 		/*
890 		 * When crypto is being done in the host we must insure
891 		 * the data are writable for the cipher routines; clone
892 		 * a writable mbuf chain.
893 		 * XXX handle SWMIC specially
894 		 */
895 		if (key->wk_flags & (IEEE80211_KEY_SWENCRYPT|IEEE80211_KEY_SWENMIC)) {
896 			m = m_unshare(m, M_NOWAIT);
897 			if (m == NULL) {
898 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
899 				    "%s: cannot get writable mbuf\n", __func__);
900 				vap->iv_stats.is_tx_nobuf++; /* XXX new stat */
901 				return NULL;
902 			}
903 		}
904 	}
905 	/*
906 	 * We know we are called just before stripping an Ethernet
907 	 * header and prepending an LLC header.  This means we know
908 	 * there will be
909 	 *	sizeof(struct ether_header) - sizeof(struct llc)
910 	 * bytes recovered to which we need additional space for the
911 	 * 802.11 header and any crypto header.
912 	 */
913 	/* XXX check trailing space and copy instead? */
914 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
915 		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
916 		if (n == NULL) {
917 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
918 			    "%s: cannot expand storage\n", __func__);
919 			vap->iv_stats.is_tx_nobuf++;
920 			m_freem(m);
921 			return NULL;
922 		}
923 		KASSERT(needed_space <= MHLEN,
924 		    ("not enough room, need %u got %zu\n", needed_space, MHLEN));
925 		/*
926 		 * Setup new mbuf to have leading space to prepend the
927 		 * 802.11 header and any crypto header bits that are
928 		 * required (the latter are added when the driver calls
929 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
930 		 */
931 		/* NB: must be first 'cuz it clobbers m_data */
932 		m_move_pkthdr(n, m);
933 		n->m_len = 0;			/* NB: m_gethdr does not set */
934 		n->m_data += needed_space;
935 		/*
936 		 * Pull up Ethernet header to create the expected layout.
937 		 * We could use m_pullup but that's overkill (i.e. we don't
938 		 * need the actual data) and it cannot fail so do it inline
939 		 * for speed.
940 		 */
941 		/* NB: struct ether_header is known to be contiguous */
942 		n->m_len += sizeof(struct ether_header);
943 		m->m_len -= sizeof(struct ether_header);
944 		m->m_data += sizeof(struct ether_header);
945 		/*
946 		 * Replace the head of the chain.
947 		 */
948 		n->m_next = m;
949 		m = n;
950 	}
951 	return m;
952 #undef TO_BE_RECLAIMED
953 }
954 
955 /*
956  * Return the transmit key to use in sending a unicast frame.
957  * If a unicast key is set we use that.  When no unicast key is set
958  * we fall back to the default transmit key.
959  */
960 static __inline struct ieee80211_key *
961 ieee80211_crypto_getucastkey(struct ieee80211vap *vap,
962 	struct ieee80211_node *ni)
963 {
964 	if (IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)) {
965 		if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
966 		    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
967 			return NULL;
968 		return &vap->iv_nw_keys[vap->iv_def_txkey];
969 	} else {
970 		return &ni->ni_ucastkey;
971 	}
972 }
973 
974 /*
975  * Return the transmit key to use in sending a multicast frame.
976  * Multicast traffic always uses the group key which is installed as
977  * the default tx key.
978  */
979 static __inline struct ieee80211_key *
980 ieee80211_crypto_getmcastkey(struct ieee80211vap *vap,
981 	struct ieee80211_node *ni)
982 {
983 	if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
984 	    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
985 		return NULL;
986 	return &vap->iv_nw_keys[vap->iv_def_txkey];
987 }
988 
989 /*
990  * Encapsulate an outbound data frame.  The mbuf chain is updated.
991  * If an error is encountered NULL is returned.  The caller is required
992  * to provide a node reference and pullup the ethernet header in the
993  * first mbuf.
994  *
995  * NB: Packet is assumed to be processed by ieee80211_classify which
996  *     marked EAPOL frames w/ M_EAPOL.
997  */
998 struct mbuf *
999 ieee80211_encap(struct ieee80211vap *vap, struct ieee80211_node *ni,
1000     struct mbuf *m)
1001 {
1002 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)(wh))
1003 	struct ieee80211com *ic = ni->ni_ic;
1004 #ifdef IEEE80211_SUPPORT_MESH
1005 	struct ieee80211_mesh_state *ms = vap->iv_mesh;
1006 	struct ieee80211_meshcntl_ae10 *mc;
1007 #endif
1008 	struct ether_header eh;
1009 	struct ieee80211_frame *wh;
1010 	struct ieee80211_key *key;
1011 	struct llc *llc;
1012 	int hdrsize, hdrspace, datalen, addqos, txfrag, is4addr;
1013 	ieee80211_seq seqno;
1014 	int meshhdrsize, meshae;
1015 	uint8_t *qos;
1016 
1017 	/*
1018 	 * Copy existing Ethernet header to a safe place.  The
1019 	 * rest of the code assumes it's ok to strip it when
1020 	 * reorganizing state for the final encapsulation.
1021 	 */
1022 	KASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
1023 	ETHER_HEADER_COPY(&eh, mtod(m, caddr_t));
1024 
1025 	/*
1026 	 * Insure space for additional headers.  First identify
1027 	 * transmit key to use in calculating any buffer adjustments
1028 	 * required.  This is also used below to do privacy
1029 	 * encapsulation work.  Then calculate the 802.11 header
1030 	 * size and any padding required by the driver.
1031 	 *
1032 	 * Note key may be NULL if we fall back to the default
1033 	 * transmit key and that is not set.  In that case the
1034 	 * buffer may not be expanded as needed by the cipher
1035 	 * routines, but they will/should discard it.
1036 	 */
1037 	if (vap->iv_flags & IEEE80211_F_PRIVACY) {
1038 		if (vap->iv_opmode == IEEE80211_M_STA ||
1039 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost) ||
1040 		    (vap->iv_opmode == IEEE80211_M_WDS &&
1041 		     (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)))
1042 			key = ieee80211_crypto_getucastkey(vap, ni);
1043 		else
1044 			key = ieee80211_crypto_getmcastkey(vap, ni);
1045 		if (key == NULL && (m->m_flags & M_EAPOL) == 0) {
1046 			IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
1047 			    eh.ether_dhost,
1048 			    "no default transmit key (%s) deftxkey %u",
1049 			    __func__, vap->iv_def_txkey);
1050 			vap->iv_stats.is_tx_nodefkey++;
1051 			goto bad;
1052 		}
1053 	} else
1054 		key = NULL;
1055 	/*
1056 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
1057 	 * frames so suppress use.  This may be an issue if other
1058 	 * ap's require all data frames to be QoS-encapsulated
1059 	 * once negotiated in which case we'll need to make this
1060 	 * configurable.
1061 	 */
1062 	addqos = (ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT)) &&
1063 		 (m->m_flags & M_EAPOL) == 0;
1064 	if (addqos)
1065 		hdrsize = sizeof(struct ieee80211_qosframe);
1066 	else
1067 		hdrsize = sizeof(struct ieee80211_frame);
1068 #ifdef IEEE80211_SUPPORT_MESH
1069 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
1070 		/*
1071 		 * Mesh data frames are encapsulated according to the
1072 		 * rules of Section 11B.8.5 (p.139 of D3.0 spec).
1073 		 * o Group Addressed data (aka multicast) originating
1074 		 *   at the local sta are sent w/ 3-address format and
1075 		 *   address extension mode 00
1076 		 * o Individually Addressed data (aka unicast) originating
1077 		 *   at the local sta are sent w/ 4-address format and
1078 		 *   address extension mode 00
1079 		 * o Group Addressed data forwarded from a non-mesh sta are
1080 		 *   sent w/ 3-address format and address extension mode 01
1081 		 * o Individually Address data from another sta are sent
1082 		 *   w/ 4-address format and address extension mode 10
1083 		 */
1084 		is4addr = 0;		/* NB: don't use, disable */
1085 		if (!IEEE80211_IS_MULTICAST(eh.ether_dhost))
1086 			hdrsize += IEEE80211_ADDR_LEN;	/* unicast are 4-addr */
1087 		meshhdrsize = sizeof(struct ieee80211_meshcntl);
1088 		/* XXX defines for AE modes */
1089 		if (IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr)) {
1090 			if (!IEEE80211_IS_MULTICAST(eh.ether_dhost))
1091 				meshae = 0;
1092 			else
1093 				meshae = 4;		/* NB: pseudo */
1094 		} else if (IEEE80211_IS_MULTICAST(eh.ether_dhost)) {
1095 			meshae = 1;
1096 			meshhdrsize += 1*IEEE80211_ADDR_LEN;
1097 		} else {
1098 			meshae = 2;
1099 			meshhdrsize += 2*IEEE80211_ADDR_LEN;
1100 		}
1101 	} else {
1102 #endif
1103 		/*
1104 		 * 4-address frames need to be generated for:
1105 		 * o packets sent through a WDS vap (IEEE80211_M_WDS)
1106 		 * o packets sent through a vap marked for relaying
1107 		 *   (e.g. a station operating with dynamic WDS)
1108 		 */
1109 		is4addr = vap->iv_opmode == IEEE80211_M_WDS ||
1110 		    ((vap->iv_flags_ext & IEEE80211_FEXT_4ADDR) &&
1111 		     !IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr));
1112 		if (is4addr)
1113 			hdrsize += IEEE80211_ADDR_LEN;
1114 		meshhdrsize = meshae = 0;
1115 #ifdef IEEE80211_SUPPORT_MESH
1116 	}
1117 #endif
1118 	/*
1119 	 * Honor driver DATAPAD requirement.
1120 	 */
1121 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
1122 		hdrspace = roundup(hdrsize, sizeof(uint32_t));
1123 	else
1124 		hdrspace = hdrsize;
1125 
1126 	if (__predict_true((m->m_flags & M_FF) == 0)) {
1127 		/*
1128 		 * Normal frame.
1129 		 */
1130 		m = ieee80211_mbuf_adjust(vap, hdrspace + meshhdrsize, key, m);
1131 		if (m == NULL) {
1132 			/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
1133 			goto bad;
1134 		}
1135 		/* NB: this could be optimized 'cuz of ieee80211_mbuf_adjust */
1136 		m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
1137 		llc = mtod(m, struct llc *);
1138 		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
1139 		llc->llc_control = LLC_UI;
1140 		llc->llc_snap.org_code[0] = 0;
1141 		llc->llc_snap.org_code[1] = 0;
1142 		llc->llc_snap.org_code[2] = 0;
1143 		llc->llc_snap.ether_type = eh.ether_type;
1144 	} else {
1145 #ifdef IEEE80211_SUPPORT_SUPERG
1146 		/*
1147 		 * Aggregated frame.
1148 		 */
1149 		m = ieee80211_ff_encap(vap, m, hdrspace + meshhdrsize, key);
1150 		if (m == NULL)
1151 #endif
1152 			goto bad;
1153 	}
1154 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
1155 
1156 	M_PREPEND(m, hdrspace + meshhdrsize, M_DONTWAIT);
1157 	if (m == NULL) {
1158 		vap->iv_stats.is_tx_nobuf++;
1159 		goto bad;
1160 	}
1161 	wh = mtod(m, struct ieee80211_frame *);
1162 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
1163 	*(uint16_t *)wh->i_dur = 0;
1164 	qos = NULL;	/* NB: quiet compiler */
1165 	if (is4addr) {
1166 		wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1167 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1168 		IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1169 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1170 		IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, eh.ether_shost);
1171 	} else switch (vap->iv_opmode) {
1172 	case IEEE80211_M_STA:
1173 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
1174 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
1175 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
1176 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1177 		break;
1178 	case IEEE80211_M_IBSS:
1179 	case IEEE80211_M_AHDEMO:
1180 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1181 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1182 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
1183 		/*
1184 		 * NB: always use the bssid from iv_bss as the
1185 		 *     neighbor's may be stale after an ibss merge
1186 		 */
1187 		IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_bss->ni_bssid);
1188 		break;
1189 	case IEEE80211_M_HOSTAP:
1190 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1191 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1192 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
1193 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
1194 		break;
1195 #ifdef IEEE80211_SUPPORT_MESH
1196 	case IEEE80211_M_MBSS:
1197 		/* NB: offset by hdrspace to deal with DATAPAD */
1198 		mc = (struct ieee80211_meshcntl_ae10 *)
1199 		     (mtod(m, uint8_t *) + hdrspace);
1200 		switch (meshae) {
1201 		case 0:			/* ucast, no proxy */
1202 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1203 			IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1204 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1205 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1206 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, eh.ether_shost);
1207 			mc->mc_flags = 0;
1208 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1209 			break;
1210 		case 4:			/* mcast, no proxy */
1211 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1212 			IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1213 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1214 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
1215 			mc->mc_flags = 0;		/* NB: AE is really 0 */
1216 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1217 			break;
1218 		case 1:			/* mcast, proxy */
1219 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1220 			IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1221 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1222 			IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_myaddr);
1223 			mc->mc_flags = 1;
1224 			IEEE80211_ADDR_COPY(mc->mc_addr4, eh.ether_shost);
1225 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1226 			break;
1227 		case 2:			/* ucast, proxy */
1228 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1229 			IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1230 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1231 			/* XXX not right, need MeshDA */
1232 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1233 			/* XXX assume are MeshSA */
1234 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, vap->iv_myaddr);
1235 			mc->mc_flags = 2;
1236 			IEEE80211_ADDR_COPY(mc->mc_addr4, eh.ether_dhost);
1237 			IEEE80211_ADDR_COPY(mc->mc_addr5, eh.ether_shost);
1238 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1239 			break;
1240 		default:
1241 			KASSERT(0, ("meshae %d", meshae));
1242 			break;
1243 		}
1244 		mc->mc_ttl = ms->ms_ttl;
1245 		ms->ms_seq++;
1246 		LE_WRITE_4(mc->mc_seq, ms->ms_seq);
1247 		break;
1248 #endif
1249 	case IEEE80211_M_WDS:		/* NB: is4addr should always be true */
1250 	default:
1251 		goto bad;
1252 	}
1253 	if (m->m_flags & M_MORE_DATA)
1254 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
1255 	if (addqos) {
1256 		int ac, tid;
1257 
1258 		if (is4addr) {
1259 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1260 		/* NB: mesh case handled earlier */
1261 		} else if (vap->iv_opmode != IEEE80211_M_MBSS)
1262 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1263 		ac = M_WME_GETAC(m);
1264 		/* map from access class/queue to 11e header priorty value */
1265 		tid = WME_AC_TO_TID(ac);
1266 		qos[0] = tid & IEEE80211_QOS_TID;
1267 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
1268 			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
1269 		qos[1] = 0;
1270 		wh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
1271 
1272 		if ((m->m_flags & M_AMPDU_MPDU) == 0) {
1273 			/*
1274 			 * NB: don't assign a sequence # to potential
1275 			 * aggregates; we expect this happens at the
1276 			 * point the frame comes off any aggregation q
1277 			 * as otherwise we may introduce holes in the
1278 			 * BA sequence space and/or make window accouting
1279 			 * more difficult.
1280 			 *
1281 			 * XXX may want to control this with a driver
1282 			 * capability; this may also change when we pull
1283 			 * aggregation up into net80211
1284 			 */
1285 			seqno = ni->ni_txseqs[tid]++;
1286 			*(uint16_t *)wh->i_seq =
1287 			    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
1288 			M_SEQNO_SET(m, seqno);
1289 		}
1290 	} else {
1291 		seqno = ni->ni_txseqs[IEEE80211_NONQOS_TID]++;
1292 		*(uint16_t *)wh->i_seq =
1293 		    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
1294 		M_SEQNO_SET(m, seqno);
1295 	}
1296 
1297 
1298 	/* check if xmit fragmentation is required */
1299 	txfrag = (m->m_pkthdr.len > vap->iv_fragthreshold &&
1300 	    !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
1301 	    (vap->iv_caps & IEEE80211_C_TXFRAG) &&
1302 	    (m->m_flags & (M_FF | M_AMPDU_MPDU)) == 0);
1303 	if (key != NULL) {
1304 		/*
1305 		 * IEEE 802.1X: send EAPOL frames always in the clear.
1306 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
1307 		 */
1308 		if ((m->m_flags & M_EAPOL) == 0 ||
1309 		    ((vap->iv_flags & IEEE80211_F_WPA) &&
1310 		     (vap->iv_opmode == IEEE80211_M_STA ?
1311 		      !IEEE80211_KEY_UNDEFINED(key) :
1312 		      !IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)))) {
1313 			wh->i_fc[1] |= IEEE80211_FC1_WEP;
1314 			if (!ieee80211_crypto_enmic(vap, key, m, txfrag)) {
1315 				IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_OUTPUT,
1316 				    eh.ether_dhost,
1317 				    "%s", "enmic failed, discard frame");
1318 				vap->iv_stats.is_crypto_enmicfail++;
1319 				goto bad;
1320 			}
1321 		}
1322 	}
1323 	if (txfrag && !ieee80211_fragment(vap, m, hdrsize,
1324 	    key != NULL ? key->wk_cipher->ic_header : 0, vap->iv_fragthreshold))
1325 		goto bad;
1326 
1327 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
1328 
1329 	IEEE80211_NODE_STAT(ni, tx_data);
1330 	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
1331 		IEEE80211_NODE_STAT(ni, tx_mcast);
1332 		m->m_flags |= M_MCAST;
1333 	} else
1334 		IEEE80211_NODE_STAT(ni, tx_ucast);
1335 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);
1336 
1337 	return m;
1338 bad:
1339 	if (m != NULL)
1340 		m_freem(m);
1341 	return NULL;
1342 #undef WH4
1343 }
1344 
1345 /*
1346  * Fragment the frame according to the specified mtu.
1347  * The size of the 802.11 header (w/o padding) is provided
1348  * so we don't need to recalculate it.  We create a new
1349  * mbuf for each fragment and chain it through m_nextpkt;
1350  * we might be able to optimize this by reusing the original
1351  * packet's mbufs but that is significantly more complicated.
1352  */
1353 static int
1354 ieee80211_fragment(struct ieee80211vap *vap, struct mbuf *m0,
1355 	u_int hdrsize, u_int ciphdrsize, u_int mtu)
1356 {
1357 	struct ieee80211_frame *wh, *whf;
1358 	struct mbuf *m, *prev, *next;
1359 	u_int totalhdrsize, fragno, fragsize, off, remainder, payload;
1360 
1361 	KASSERT(m0->m_nextpkt == NULL, ("mbuf already chained?"));
1362 	KASSERT(m0->m_pkthdr.len > mtu,
1363 		("pktlen %u mtu %u", m0->m_pkthdr.len, mtu));
1364 
1365 	wh = mtod(m0, struct ieee80211_frame *);
1366 	/* NB: mark the first frag; it will be propagated below */
1367 	wh->i_fc[1] |= IEEE80211_FC1_MORE_FRAG;
1368 	totalhdrsize = hdrsize + ciphdrsize;
1369 	fragno = 1;
1370 	off = mtu - ciphdrsize;
1371 	remainder = m0->m_pkthdr.len - off;
1372 	prev = m0;
1373 	do {
1374 		fragsize = totalhdrsize + remainder;
1375 		if (fragsize > mtu)
1376 			fragsize = mtu;
1377 		/* XXX fragsize can be >2048! */
1378 		KASSERT(fragsize < MCLBYTES,
1379 			("fragment size %u too big!", fragsize));
1380 		if (fragsize > MHLEN)
1381 			m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
1382 		else
1383 			m = m_gethdr(M_DONTWAIT, MT_DATA);
1384 		if (m == NULL)
1385 			goto bad;
1386 		/* leave room to prepend any cipher header */
1387 		m_align(m, fragsize - ciphdrsize);
1388 
1389 		/*
1390 		 * Form the header in the fragment.  Note that since
1391 		 * we mark the first fragment with the MORE_FRAG bit
1392 		 * it automatically is propagated to each fragment; we
1393 		 * need only clear it on the last fragment (done below).
1394 		 */
1395 		whf = mtod(m, struct ieee80211_frame *);
1396 		memcpy(whf, wh, hdrsize);
1397 		*(uint16_t *)&whf->i_seq[0] |= htole16(
1398 			(fragno & IEEE80211_SEQ_FRAG_MASK) <<
1399 				IEEE80211_SEQ_FRAG_SHIFT);
1400 		fragno++;
1401 
1402 		payload = fragsize - totalhdrsize;
1403 		/* NB: destination is known to be contiguous */
1404 		m_copydata(m0, off, payload, mtod(m, uint8_t *) + hdrsize);
1405 		m->m_len = hdrsize + payload;
1406 		m->m_pkthdr.len = hdrsize + payload;
1407 		m->m_flags |= M_FRAG;
1408 
1409 		/* chain up the fragment */
1410 		prev->m_nextpkt = m;
1411 		prev = m;
1412 
1413 		/* deduct fragment just formed */
1414 		remainder -= payload;
1415 		off += payload;
1416 	} while (remainder != 0);
1417 
1418 	/* set the last fragment */
1419 	m->m_flags |= M_LASTFRAG;
1420 	whf->i_fc[1] &= ~IEEE80211_FC1_MORE_FRAG;
1421 
1422 	/* strip first mbuf now that everything has been copied */
1423 	m_adj(m0, -(m0->m_pkthdr.len - (mtu - ciphdrsize)));
1424 	m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1425 
1426 	vap->iv_stats.is_tx_fragframes++;
1427 	vap->iv_stats.is_tx_frags += fragno-1;
1428 
1429 	return 1;
1430 bad:
1431 	/* reclaim fragments but leave original frame for caller to free */
1432 	for (m = m0->m_nextpkt; m != NULL; m = next) {
1433 		next = m->m_nextpkt;
1434 		m->m_nextpkt = NULL;		/* XXX paranoid */
1435 		m_freem(m);
1436 	}
1437 	m0->m_nextpkt = NULL;
1438 	return 0;
1439 }
1440 
1441 /*
1442  * Add a supported rates element id to a frame.
1443  */
1444 uint8_t *
1445 ieee80211_add_rates(uint8_t *frm, const struct ieee80211_rateset *rs)
1446 {
1447 	int nrates;
1448 
1449 	*frm++ = IEEE80211_ELEMID_RATES;
1450 	nrates = rs->rs_nrates;
1451 	if (nrates > IEEE80211_RATE_SIZE)
1452 		nrates = IEEE80211_RATE_SIZE;
1453 	*frm++ = nrates;
1454 	memcpy(frm, rs->rs_rates, nrates);
1455 	return frm + nrates;
1456 }
1457 
1458 /*
1459  * Add an extended supported rates element id to a frame.
1460  */
1461 uint8_t *
1462 ieee80211_add_xrates(uint8_t *frm, const struct ieee80211_rateset *rs)
1463 {
1464 	/*
1465 	 * Add an extended supported rates element if operating in 11g mode.
1466 	 */
1467 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
1468 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
1469 		*frm++ = IEEE80211_ELEMID_XRATES;
1470 		*frm++ = nrates;
1471 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
1472 		frm += nrates;
1473 	}
1474 	return frm;
1475 }
1476 
1477 /*
1478  * Add an ssid element to a frame.
1479  */
1480 static uint8_t *
1481 ieee80211_add_ssid(uint8_t *frm, const uint8_t *ssid, u_int len)
1482 {
1483 	*frm++ = IEEE80211_ELEMID_SSID;
1484 	*frm++ = len;
1485 	memcpy(frm, ssid, len);
1486 	return frm + len;
1487 }
1488 
1489 /*
1490  * Add an erp element to a frame.
1491  */
1492 static uint8_t *
1493 ieee80211_add_erp(uint8_t *frm, struct ieee80211com *ic)
1494 {
1495 	uint8_t erp;
1496 
1497 	*frm++ = IEEE80211_ELEMID_ERP;
1498 	*frm++ = 1;
1499 	erp = 0;
1500 	if (ic->ic_nonerpsta != 0)
1501 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
1502 	if (ic->ic_flags & IEEE80211_F_USEPROT)
1503 		erp |= IEEE80211_ERP_USE_PROTECTION;
1504 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
1505 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
1506 	*frm++ = erp;
1507 	return frm;
1508 }
1509 
1510 /*
1511  * Add a CFParams element to a frame.
1512  */
1513 static uint8_t *
1514 ieee80211_add_cfparms(uint8_t *frm, struct ieee80211com *ic)
1515 {
1516 #define	ADDSHORT(frm, v) do {	\
1517 	LE_WRITE_2(frm, v);	\
1518 	frm += 2;		\
1519 } while (0)
1520 	*frm++ = IEEE80211_ELEMID_CFPARMS;
1521 	*frm++ = 6;
1522 	*frm++ = 0;		/* CFP count */
1523 	*frm++ = 2;		/* CFP period */
1524 	ADDSHORT(frm, 0);	/* CFP MaxDuration (TU) */
1525 	ADDSHORT(frm, 0);	/* CFP CurRemaining (TU) */
1526 	return frm;
1527 #undef ADDSHORT
1528 }
1529 
1530 static __inline uint8_t *
1531 add_appie(uint8_t *frm, const struct ieee80211_appie *ie)
1532 {
1533 	memcpy(frm, ie->ie_data, ie->ie_len);
1534 	return frm + ie->ie_len;
1535 }
1536 
1537 static __inline uint8_t *
1538 add_ie(uint8_t *frm, const uint8_t *ie)
1539 {
1540 	memcpy(frm, ie, 2 + ie[1]);
1541 	return frm + 2 + ie[1];
1542 }
1543 
1544 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
1545 /*
1546  * Add a WME information element to a frame.
1547  */
1548 static uint8_t *
1549 ieee80211_add_wme_info(uint8_t *frm, struct ieee80211_wme_state *wme)
1550 {
1551 	static const struct ieee80211_wme_info info = {
1552 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1553 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
1554 		.wme_oui	= { WME_OUI_BYTES },
1555 		.wme_type	= WME_OUI_TYPE,
1556 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
1557 		.wme_version	= WME_VERSION,
1558 		.wme_info	= 0,
1559 	};
1560 	memcpy(frm, &info, sizeof(info));
1561 	return frm + sizeof(info);
1562 }
1563 
1564 /*
1565  * Add a WME parameters element to a frame.
1566  */
1567 static uint8_t *
1568 ieee80211_add_wme_param(uint8_t *frm, struct ieee80211_wme_state *wme)
1569 {
1570 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
1571 #define	ADDSHORT(frm, v) do {	\
1572 	LE_WRITE_2(frm, v);	\
1573 	frm += 2;		\
1574 } while (0)
1575 	/* NB: this works 'cuz a param has an info at the front */
1576 	static const struct ieee80211_wme_info param = {
1577 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1578 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
1579 		.wme_oui	= { WME_OUI_BYTES },
1580 		.wme_type	= WME_OUI_TYPE,
1581 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
1582 		.wme_version	= WME_VERSION,
1583 	};
1584 	int i;
1585 
1586 	memcpy(frm, &param, sizeof(param));
1587 	frm += __offsetof(struct ieee80211_wme_info, wme_info);
1588 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
1589 	*frm++ = 0;					/* reserved field */
1590 	for (i = 0; i < WME_NUM_AC; i++) {
1591 		const struct wmeParams *ac =
1592 		       &wme->wme_bssChanParams.cap_wmeParams[i];
1593 		*frm++ = SM(i, WME_PARAM_ACI)
1594 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
1595 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
1596 		       ;
1597 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
1598 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
1599 		       ;
1600 		ADDSHORT(frm, ac->wmep_txopLimit);
1601 	}
1602 	return frm;
1603 #undef SM
1604 #undef ADDSHORT
1605 }
1606 #undef WME_OUI_BYTES
1607 
1608 /*
1609  * Add an 11h Power Constraint element to a frame.
1610  */
1611 static uint8_t *
1612 ieee80211_add_powerconstraint(uint8_t *frm, struct ieee80211vap *vap)
1613 {
1614 	const struct ieee80211_channel *c = vap->iv_bss->ni_chan;
1615 	/* XXX per-vap tx power limit? */
1616 	int8_t limit = vap->iv_ic->ic_txpowlimit / 2;
1617 
1618 	frm[0] = IEEE80211_ELEMID_PWRCNSTR;
1619 	frm[1] = 1;
1620 	frm[2] = c->ic_maxregpower > limit ?  c->ic_maxregpower - limit : 0;
1621 	return frm + 3;
1622 }
1623 
1624 /*
1625  * Add an 11h Power Capability element to a frame.
1626  */
1627 static uint8_t *
1628 ieee80211_add_powercapability(uint8_t *frm, const struct ieee80211_channel *c)
1629 {
1630 	frm[0] = IEEE80211_ELEMID_PWRCAP;
1631 	frm[1] = 2;
1632 	frm[2] = c->ic_minpower;
1633 	frm[3] = c->ic_maxpower;
1634 	return frm + 4;
1635 }
1636 
1637 /*
1638  * Add an 11h Supported Channels element to a frame.
1639  */
1640 static uint8_t *
1641 ieee80211_add_supportedchannels(uint8_t *frm, struct ieee80211com *ic)
1642 {
1643 	static const int ielen = 26;
1644 
1645 	frm[0] = IEEE80211_ELEMID_SUPPCHAN;
1646 	frm[1] = ielen;
1647 	/* XXX not correct */
1648 	memcpy(frm+2, ic->ic_chan_avail, ielen);
1649 	return frm + 2 + ielen;
1650 }
1651 
1652 /*
1653  * Add an 11h Channel Switch Announcement element to a frame.
1654  * Note that we use the per-vap CSA count to adjust the global
1655  * counter so we can use this routine to form probe response
1656  * frames and get the current count.
1657  */
1658 static uint8_t *
1659 ieee80211_add_csa(uint8_t *frm, struct ieee80211vap *vap)
1660 {
1661 	struct ieee80211com *ic = vap->iv_ic;
1662 	struct ieee80211_csa_ie *csa = (struct ieee80211_csa_ie *) frm;
1663 
1664 	csa->csa_ie = IEEE80211_ELEMID_CSA;
1665 	csa->csa_len = 3;
1666 	csa->csa_mode = 1;		/* XXX force quiet on channel */
1667 	csa->csa_newchan = ieee80211_chan2ieee(ic, ic->ic_csa_newchan);
1668 	csa->csa_count = ic->ic_csa_count - vap->iv_csa_count;
1669 	return frm + sizeof(*csa);
1670 }
1671 
1672 /*
1673  * Add an 11h country information element to a frame.
1674  */
1675 static uint8_t *
1676 ieee80211_add_countryie(uint8_t *frm, struct ieee80211com *ic)
1677 {
1678 
1679 	if (ic->ic_countryie == NULL ||
1680 	    ic->ic_countryie_chan != ic->ic_bsschan) {
1681 		/*
1682 		 * Handle lazy construction of ie.  This is done on
1683 		 * first use and after a channel change that requires
1684 		 * re-calculation.
1685 		 */
1686 		if (ic->ic_countryie != NULL)
1687 			free(ic->ic_countryie, M_80211_NODE_IE);
1688 		ic->ic_countryie = ieee80211_alloc_countryie(ic);
1689 		if (ic->ic_countryie == NULL)
1690 			return frm;
1691 		ic->ic_countryie_chan = ic->ic_bsschan;
1692 	}
1693 	return add_appie(frm, ic->ic_countryie);
1694 }
1695 
1696 /*
1697  * Send a probe request frame with the specified ssid
1698  * and any optional information element data.
1699  */
1700 int
1701 ieee80211_send_probereq(struct ieee80211_node *ni,
1702 	const uint8_t sa[IEEE80211_ADDR_LEN],
1703 	const uint8_t da[IEEE80211_ADDR_LEN],
1704 	const uint8_t bssid[IEEE80211_ADDR_LEN],
1705 	const uint8_t *ssid, size_t ssidlen)
1706 {
1707 	struct ieee80211vap *vap = ni->ni_vap;
1708 	struct ieee80211com *ic = ni->ni_ic;
1709 	const struct ieee80211_txparam *tp;
1710 	struct ieee80211_bpf_params params;
1711 	struct ieee80211_frame *wh;
1712 	const struct ieee80211_rateset *rs;
1713 	struct mbuf *m;
1714 	uint8_t *frm;
1715 
1716 	if (vap->iv_state == IEEE80211_S_CAC) {
1717 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, ni,
1718 		    "block %s frame in CAC state", "probe request");
1719 		vap->iv_stats.is_tx_badstate++;
1720 		return EIO;		/* XXX */
1721 	}
1722 
1723 	/*
1724 	 * Hold a reference on the node so it doesn't go away until after
1725 	 * the xmit is complete all the way in the driver.  On error we
1726 	 * will remove our reference.
1727 	 */
1728 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
1729 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1730 		__func__, __LINE__,
1731 		ni, ether_sprintf(ni->ni_macaddr),
1732 		ieee80211_node_refcnt(ni)+1);
1733 	ieee80211_ref_node(ni);
1734 
1735 	/*
1736 	 * prreq frame format
1737 	 *	[tlv] ssid
1738 	 *	[tlv] supported rates
1739 	 *	[tlv] RSN (optional)
1740 	 *	[tlv] extended supported rates
1741 	 *	[tlv] WPA (optional)
1742 	 *	[tlv] user-specified ie's
1743 	 */
1744 	m = ieee80211_getmgtframe(&frm,
1745 		 ic->ic_headroom + sizeof(struct ieee80211_frame),
1746 	       	 2 + IEEE80211_NWID_LEN
1747 	       + 2 + IEEE80211_RATE_SIZE
1748 	       + sizeof(struct ieee80211_ie_wpa)
1749 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1750 	       + sizeof(struct ieee80211_ie_wpa)
1751 	       + (vap->iv_appie_probereq != NULL ?
1752 		   vap->iv_appie_probereq->ie_len : 0)
1753 	);
1754 	if (m == NULL) {
1755 		vap->iv_stats.is_tx_nobuf++;
1756 		ieee80211_free_node(ni);
1757 		return ENOMEM;
1758 	}
1759 
1760 	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
1761 	rs = ieee80211_get_suprates(ic, ic->ic_curchan);
1762 	frm = ieee80211_add_rates(frm, rs);
1763 	if (vap->iv_flags & IEEE80211_F_WPA2) {
1764 		if (vap->iv_rsn_ie != NULL)
1765 			frm = add_ie(frm, vap->iv_rsn_ie);
1766 		/* XXX else complain? */
1767 	}
1768 	frm = ieee80211_add_xrates(frm, rs);
1769 	if (vap->iv_flags & IEEE80211_F_WPA1) {
1770 		if (vap->iv_wpa_ie != NULL)
1771 			frm = add_ie(frm, vap->iv_wpa_ie);
1772 		/* XXX else complain? */
1773 	}
1774 	if (vap->iv_appie_probereq != NULL)
1775 		frm = add_appie(frm, vap->iv_appie_probereq);
1776 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
1777 
1778 	KASSERT(M_LEADINGSPACE(m) >= sizeof(struct ieee80211_frame),
1779 	    ("leading space %zd", M_LEADINGSPACE(m)));
1780 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1781 	if (m == NULL) {
1782 		/* NB: cannot happen */
1783 		ieee80211_free_node(ni);
1784 		return ENOMEM;
1785 	}
1786 
1787 	wh = mtod(m, struct ieee80211_frame *);
1788 	ieee80211_send_setup(ni, m,
1789 	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
1790 	     IEEE80211_NONQOS_TID, sa, da, bssid);
1791 	/* XXX power management? */
1792 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
1793 
1794 	M_WME_SETAC(m, WME_AC_BE);
1795 
1796 	IEEE80211_NODE_STAT(ni, tx_probereq);
1797 	IEEE80211_NODE_STAT(ni, tx_mgmt);
1798 
1799 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
1800 	    "send probe req on channel %u bssid %s ssid \"%.*s\"\n",
1801 	    ieee80211_chan2ieee(ic, ic->ic_curchan), ether_sprintf(bssid),
1802 	    ssidlen, ssid);
1803 
1804 	memset(&params, 0, sizeof(params));
1805 	params.ibp_pri = M_WME_GETAC(m);
1806 	tp = &vap->iv_txparms[ieee80211_chan2mode(ic->ic_curchan)];
1807 	params.ibp_rate0 = tp->mgmtrate;
1808 	if (IEEE80211_IS_MULTICAST(da)) {
1809 		params.ibp_flags |= IEEE80211_BPF_NOACK;
1810 		params.ibp_try0 = 1;
1811 	} else
1812 		params.ibp_try0 = tp->maxretry;
1813 	params.ibp_power = ni->ni_txpower;
1814 	return ic->ic_raw_xmit(ni, m, &params);
1815 }
1816 
1817 /*
1818  * Calculate capability information for mgt frames.
1819  */
1820 uint16_t
1821 ieee80211_getcapinfo(struct ieee80211vap *vap, struct ieee80211_channel *chan)
1822 {
1823 	struct ieee80211com *ic = vap->iv_ic;
1824 	uint16_t capinfo;
1825 
1826 	KASSERT(vap->iv_opmode != IEEE80211_M_STA, ("station mode"));
1827 
1828 	if (vap->iv_opmode == IEEE80211_M_HOSTAP)
1829 		capinfo = IEEE80211_CAPINFO_ESS;
1830 	else if (vap->iv_opmode == IEEE80211_M_IBSS)
1831 		capinfo = IEEE80211_CAPINFO_IBSS;
1832 	else
1833 		capinfo = 0;
1834 	if (vap->iv_flags & IEEE80211_F_PRIVACY)
1835 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1836 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1837 	    IEEE80211_IS_CHAN_2GHZ(chan))
1838 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1839 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1840 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1841 	if (IEEE80211_IS_CHAN_5GHZ(chan) && (vap->iv_flags & IEEE80211_F_DOTH))
1842 		capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
1843 	return capinfo;
1844 }
1845 
1846 /*
1847  * Send a management frame.  The node is for the destination (or ic_bss
1848  * when in station mode).  Nodes other than ic_bss have their reference
1849  * count bumped to reflect our use for an indeterminant time.
1850  */
1851 int
1852 ieee80211_send_mgmt(struct ieee80211_node *ni, int type, int arg)
1853 {
1854 #define	HTFLAGS (IEEE80211_NODE_HT | IEEE80211_NODE_HTCOMPAT)
1855 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
1856 	struct ieee80211vap *vap = ni->ni_vap;
1857 	struct ieee80211com *ic = ni->ni_ic;
1858 	struct ieee80211_node *bss = vap->iv_bss;
1859 	struct ieee80211_bpf_params params;
1860 	struct mbuf *m;
1861 	uint8_t *frm;
1862 	uint16_t capinfo;
1863 	int has_challenge, is_shared_key, ret, status;
1864 
1865 	KASSERT(ni != NULL, ("null node"));
1866 
1867 	/*
1868 	 * Hold a reference on the node so it doesn't go away until after
1869 	 * the xmit is complete all the way in the driver.  On error we
1870 	 * will remove our reference.
1871 	 */
1872 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
1873 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1874 		__func__, __LINE__,
1875 		ni, ether_sprintf(ni->ni_macaddr),
1876 		ieee80211_node_refcnt(ni)+1);
1877 	ieee80211_ref_node(ni);
1878 
1879 	memset(&params, 0, sizeof(params));
1880 	switch (type) {
1881 
1882 	case IEEE80211_FC0_SUBTYPE_AUTH:
1883 		status = arg >> 16;
1884 		arg &= 0xffff;
1885 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1886 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1887 		    ni->ni_challenge != NULL);
1888 
1889 		/*
1890 		 * Deduce whether we're doing open authentication or
1891 		 * shared key authentication.  We do the latter if
1892 		 * we're in the middle of a shared key authentication
1893 		 * handshake or if we're initiating an authentication
1894 		 * request and configured to use shared key.
1895 		 */
1896 		is_shared_key = has_challenge ||
1897 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1898 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1899 		      bss->ni_authmode == IEEE80211_AUTH_SHARED);
1900 
1901 		m = ieee80211_getmgtframe(&frm,
1902 			  ic->ic_headroom + sizeof(struct ieee80211_frame),
1903 			  3 * sizeof(uint16_t)
1904 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1905 				sizeof(uint16_t)+IEEE80211_CHALLENGE_LEN : 0)
1906 		);
1907 		if (m == NULL)
1908 			senderr(ENOMEM, is_tx_nobuf);
1909 
1910 		((uint16_t *)frm)[0] =
1911 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1912 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1913 		((uint16_t *)frm)[1] = htole16(arg);	/* sequence number */
1914 		((uint16_t *)frm)[2] = htole16(status);/* status */
1915 
1916 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1917 			((uint16_t *)frm)[3] =
1918 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1919 			    IEEE80211_ELEMID_CHALLENGE);
1920 			memcpy(&((uint16_t *)frm)[4], ni->ni_challenge,
1921 			    IEEE80211_CHALLENGE_LEN);
1922 			m->m_pkthdr.len = m->m_len =
1923 				4 * sizeof(uint16_t) + IEEE80211_CHALLENGE_LEN;
1924 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1925 				IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
1926 				    "request encrypt frame (%s)", __func__);
1927 				/* mark frame for encryption */
1928 				params.ibp_flags |= IEEE80211_BPF_CRYPTO;
1929 			}
1930 		} else
1931 			m->m_pkthdr.len = m->m_len = 3 * sizeof(uint16_t);
1932 
1933 		/* XXX not right for shared key */
1934 		if (status == IEEE80211_STATUS_SUCCESS)
1935 			IEEE80211_NODE_STAT(ni, tx_auth);
1936 		else
1937 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1938 
1939 		if (vap->iv_opmode == IEEE80211_M_STA)
1940 			ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
1941 				(void *) vap->iv_state);
1942 		break;
1943 
1944 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1945 		IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
1946 		    "send station deauthenticate (reason %d)", arg);
1947 		m = ieee80211_getmgtframe(&frm,
1948 			ic->ic_headroom + sizeof(struct ieee80211_frame),
1949 			sizeof(uint16_t));
1950 		if (m == NULL)
1951 			senderr(ENOMEM, is_tx_nobuf);
1952 		*(uint16_t *)frm = htole16(arg);	/* reason */
1953 		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);
1954 
1955 		IEEE80211_NODE_STAT(ni, tx_deauth);
1956 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1957 
1958 		ieee80211_node_unauthorize(ni);		/* port closed */
1959 		break;
1960 
1961 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1962 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1963 		/*
1964 		 * asreq frame format
1965 		 *	[2] capability information
1966 		 *	[2] listen interval
1967 		 *	[6*] current AP address (reassoc only)
1968 		 *	[tlv] ssid
1969 		 *	[tlv] supported rates
1970 		 *	[tlv] extended supported rates
1971 		 *	[4] power capability (optional)
1972 		 *	[28] supported channels (optional)
1973 		 *	[tlv] HT capabilities
1974 		 *	[tlv] WME (optional)
1975 		 *	[tlv] Vendor OUI HT capabilities (optional)
1976 		 *	[tlv] Atheros capabilities (if negotiated)
1977 		 *	[tlv] AppIE's (optional)
1978 		 */
1979 		m = ieee80211_getmgtframe(&frm,
1980 			 ic->ic_headroom + sizeof(struct ieee80211_frame),
1981 			 sizeof(uint16_t)
1982 		       + sizeof(uint16_t)
1983 		       + IEEE80211_ADDR_LEN
1984 		       + 2 + IEEE80211_NWID_LEN
1985 		       + 2 + IEEE80211_RATE_SIZE
1986 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1987 		       + 4
1988 		       + 2 + 26
1989 		       + sizeof(struct ieee80211_wme_info)
1990 		       + sizeof(struct ieee80211_ie_htcap)
1991 		       + 4 + sizeof(struct ieee80211_ie_htcap)
1992 #ifdef IEEE80211_SUPPORT_SUPERG
1993 		       + sizeof(struct ieee80211_ath_ie)
1994 #endif
1995 		       + (vap->iv_appie_wpa != NULL ?
1996 				vap->iv_appie_wpa->ie_len : 0)
1997 		       + (vap->iv_appie_assocreq != NULL ?
1998 				vap->iv_appie_assocreq->ie_len : 0)
1999 		);
2000 		if (m == NULL)
2001 			senderr(ENOMEM, is_tx_nobuf);
2002 
2003 		KASSERT(vap->iv_opmode == IEEE80211_M_STA,
2004 		    ("wrong mode %u", vap->iv_opmode));
2005 		capinfo = IEEE80211_CAPINFO_ESS;
2006 		if (vap->iv_flags & IEEE80211_F_PRIVACY)
2007 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
2008 		/*
2009 		 * NB: Some 11a AP's reject the request when
2010 		 *     short premable is set.
2011 		 */
2012 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
2013 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
2014 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
2015 		if (IEEE80211_IS_CHAN_ANYG(ic->ic_curchan) &&
2016 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
2017 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
2018 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) &&
2019 		    (vap->iv_flags & IEEE80211_F_DOTH))
2020 			capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
2021 		*(uint16_t *)frm = htole16(capinfo);
2022 		frm += 2;
2023 
2024 		KASSERT(bss->ni_intval != 0, ("beacon interval is zero!"));
2025 		*(uint16_t *)frm = htole16(howmany(ic->ic_lintval,
2026 						    bss->ni_intval));
2027 		frm += 2;
2028 
2029 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
2030 			IEEE80211_ADDR_COPY(frm, bss->ni_bssid);
2031 			frm += IEEE80211_ADDR_LEN;
2032 		}
2033 
2034 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
2035 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
2036 		if (vap->iv_flags & IEEE80211_F_WPA2) {
2037 			if (vap->iv_rsn_ie != NULL)
2038 				frm = add_ie(frm, vap->iv_rsn_ie);
2039 			/* XXX else complain? */
2040 		}
2041 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
2042 		if (capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) {
2043 			frm = ieee80211_add_powercapability(frm,
2044 			    ic->ic_curchan);
2045 			frm = ieee80211_add_supportedchannels(frm, ic);
2046 		}
2047 		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
2048 		    ni->ni_ies.htcap_ie != NULL &&
2049 		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_HTCAP)
2050 			frm = ieee80211_add_htcap(frm, ni);
2051 		if (vap->iv_flags & IEEE80211_F_WPA1) {
2052 			if (vap->iv_wpa_ie != NULL)
2053 				frm = add_ie(frm, vap->iv_wpa_ie);
2054 			/* XXX else complain */
2055 		}
2056 		if ((ic->ic_flags & IEEE80211_F_WME) &&
2057 		    ni->ni_ies.wme_ie != NULL)
2058 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
2059 		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
2060 		    ni->ni_ies.htcap_ie != NULL &&
2061 		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_VENDOR)
2062 			frm = ieee80211_add_htcap_vendor(frm, ni);
2063 #ifdef IEEE80211_SUPPORT_SUPERG
2064 		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS)) {
2065 			frm = ieee80211_add_ath(frm,
2066 				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
2067 				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
2068 				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
2069 				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
2070 		}
2071 #endif /* IEEE80211_SUPPORT_SUPERG */
2072 		if (vap->iv_appie_assocreq != NULL)
2073 			frm = add_appie(frm, vap->iv_appie_assocreq);
2074 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2075 
2076 		ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
2077 			(void *) vap->iv_state);
2078 		break;
2079 
2080 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
2081 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
2082 		/*
2083 		 * asresp frame format
2084 		 *	[2] capability information
2085 		 *	[2] status
2086 		 *	[2] association ID
2087 		 *	[tlv] supported rates
2088 		 *	[tlv] extended supported rates
2089 		 *	[tlv] HT capabilities (standard, if STA enabled)
2090 		 *	[tlv] HT information (standard, if STA enabled)
2091 		 *	[tlv] WME (if configured and STA enabled)
2092 		 *	[tlv] HT capabilities (vendor OUI, if STA enabled)
2093 		 *	[tlv] HT information (vendor OUI, if STA enabled)
2094 		 *	[tlv] Atheros capabilities (if STA enabled)
2095 		 *	[tlv] AppIE's (optional)
2096 		 */
2097 		m = ieee80211_getmgtframe(&frm,
2098 			 ic->ic_headroom + sizeof(struct ieee80211_frame),
2099 			 sizeof(uint16_t)
2100 		       + sizeof(uint16_t)
2101 		       + sizeof(uint16_t)
2102 		       + 2 + IEEE80211_RATE_SIZE
2103 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2104 		       + sizeof(struct ieee80211_ie_htcap) + 4
2105 		       + sizeof(struct ieee80211_ie_htinfo) + 4
2106 		       + sizeof(struct ieee80211_wme_param)
2107 #ifdef IEEE80211_SUPPORT_SUPERG
2108 		       + sizeof(struct ieee80211_ath_ie)
2109 #endif
2110 		       + (vap->iv_appie_assocresp != NULL ?
2111 				vap->iv_appie_assocresp->ie_len : 0)
2112 		);
2113 		if (m == NULL)
2114 			senderr(ENOMEM, is_tx_nobuf);
2115 
2116 		capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
2117 		*(uint16_t *)frm = htole16(capinfo);
2118 		frm += 2;
2119 
2120 		*(uint16_t *)frm = htole16(arg);	/* status */
2121 		frm += 2;
2122 
2123 		if (arg == IEEE80211_STATUS_SUCCESS) {
2124 			*(uint16_t *)frm = htole16(ni->ni_associd);
2125 			IEEE80211_NODE_STAT(ni, tx_assoc);
2126 		} else
2127 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
2128 		frm += 2;
2129 
2130 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
2131 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
2132 		/* NB: respond according to what we received */
2133 		if ((ni->ni_flags & HTFLAGS) == IEEE80211_NODE_HT) {
2134 			frm = ieee80211_add_htcap(frm, ni);
2135 			frm = ieee80211_add_htinfo(frm, ni);
2136 		}
2137 		if ((vap->iv_flags & IEEE80211_F_WME) &&
2138 		    ni->ni_ies.wme_ie != NULL)
2139 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2140 		if ((ni->ni_flags & HTFLAGS) == HTFLAGS) {
2141 			frm = ieee80211_add_htcap_vendor(frm, ni);
2142 			frm = ieee80211_add_htinfo_vendor(frm, ni);
2143 		}
2144 #ifdef IEEE80211_SUPPORT_SUPERG
2145 		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS))
2146 			frm = ieee80211_add_ath(frm,
2147 				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
2148 				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
2149 				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
2150 				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
2151 #endif /* IEEE80211_SUPPORT_SUPERG */
2152 		if (vap->iv_appie_assocresp != NULL)
2153 			frm = add_appie(frm, vap->iv_appie_assocresp);
2154 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2155 		break;
2156 
2157 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
2158 		IEEE80211_NOTE(vap, IEEE80211_MSG_ASSOC, ni,
2159 		    "send station disassociate (reason %d)", arg);
2160 		m = ieee80211_getmgtframe(&frm,
2161 			ic->ic_headroom + sizeof(struct ieee80211_frame),
2162 			sizeof(uint16_t));
2163 		if (m == NULL)
2164 			senderr(ENOMEM, is_tx_nobuf);
2165 		*(uint16_t *)frm = htole16(arg);	/* reason */
2166 		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);
2167 
2168 		IEEE80211_NODE_STAT(ni, tx_disassoc);
2169 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
2170 		break;
2171 
2172 	default:
2173 		IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
2174 		    "invalid mgmt frame type %u", type);
2175 		senderr(EINVAL, is_tx_unknownmgt);
2176 		/* NOTREACHED */
2177 	}
2178 
2179 	/* NB: force non-ProbeResp frames to the highest queue */
2180 	params.ibp_pri = WME_AC_VO;
2181 	params.ibp_rate0 = bss->ni_txparms->mgmtrate;
2182 	/* NB: we know all frames are unicast */
2183 	params.ibp_try0 = bss->ni_txparms->maxretry;
2184 	params.ibp_power = bss->ni_txpower;
2185 	return ieee80211_mgmt_output(ni, m, type, &params);
2186 bad:
2187 	ieee80211_free_node(ni);
2188 	return ret;
2189 #undef senderr
2190 #undef HTFLAGS
2191 }
2192 
2193 /*
2194  * Return an mbuf with a probe response frame in it.
2195  * Space is left to prepend and 802.11 header at the
2196  * front but it's left to the caller to fill in.
2197  */
2198 struct mbuf *
2199 ieee80211_alloc_proberesp(struct ieee80211_node *bss, int legacy)
2200 {
2201 	struct ieee80211vap *vap = bss->ni_vap;
2202 	struct ieee80211com *ic = bss->ni_ic;
2203 	const struct ieee80211_rateset *rs;
2204 	struct mbuf *m;
2205 	uint16_t capinfo;
2206 	uint8_t *frm;
2207 
2208 	/*
2209 	 * probe response frame format
2210 	 *	[8] time stamp
2211 	 *	[2] beacon interval
2212 	 *	[2] cabability information
2213 	 *	[tlv] ssid
2214 	 *	[tlv] supported rates
2215 	 *	[tlv] parameter set (FH/DS)
2216 	 *	[tlv] parameter set (IBSS)
2217 	 *	[tlv] country (optional)
2218 	 *	[3] power control (optional)
2219 	 *	[5] channel switch announcement (CSA) (optional)
2220 	 *	[tlv] extended rate phy (ERP)
2221 	 *	[tlv] extended supported rates
2222 	 *	[tlv] RSN (optional)
2223 	 *	[tlv] HT capabilities
2224 	 *	[tlv] HT information
2225 	 *	[tlv] WPA (optional)
2226 	 *	[tlv] WME (optional)
2227 	 *	[tlv] Vendor OUI HT capabilities (optional)
2228 	 *	[tlv] Vendor OUI HT information (optional)
2229 	 *	[tlv] Atheros capabilities
2230 	 *	[tlv] AppIE's (optional)
2231 	 *	[tlv] Mesh ID (MBSS)
2232 	 *	[tlv] Mesh Conf (MBSS)
2233 	 */
2234 	m = ieee80211_getmgtframe(&frm,
2235 		 ic->ic_headroom + sizeof(struct ieee80211_frame),
2236 		 8
2237 	       + sizeof(uint16_t)
2238 	       + sizeof(uint16_t)
2239 	       + 2 + IEEE80211_NWID_LEN
2240 	       + 2 + IEEE80211_RATE_SIZE
2241 	       + 7	/* max(7,3) */
2242 	       + IEEE80211_COUNTRY_MAX_SIZE
2243 	       + 3
2244 	       + sizeof(struct ieee80211_csa_ie)
2245 	       + 3
2246 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2247 	       + sizeof(struct ieee80211_ie_wpa)
2248 	       + sizeof(struct ieee80211_ie_htcap)
2249 	       + sizeof(struct ieee80211_ie_htinfo)
2250 	       + sizeof(struct ieee80211_ie_wpa)
2251 	       + sizeof(struct ieee80211_wme_param)
2252 	       + 4 + sizeof(struct ieee80211_ie_htcap)
2253 	       + 4 + sizeof(struct ieee80211_ie_htinfo)
2254 #ifdef IEEE80211_SUPPORT_SUPERG
2255 	       + sizeof(struct ieee80211_ath_ie)
2256 #endif
2257 #ifdef IEEE80211_SUPPORT_MESH
2258 	       + 2 + IEEE80211_MESHID_LEN
2259 	       + sizeof(struct ieee80211_meshconf_ie)
2260 #endif
2261 	       + (vap->iv_appie_proberesp != NULL ?
2262 			vap->iv_appie_proberesp->ie_len : 0)
2263 	);
2264 	if (m == NULL) {
2265 		vap->iv_stats.is_tx_nobuf++;
2266 		return NULL;
2267 	}
2268 
2269 	memset(frm, 0, 8);	/* timestamp should be filled later */
2270 	frm += 8;
2271 	*(uint16_t *)frm = htole16(bss->ni_intval);
2272 	frm += 2;
2273 	capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
2274 	*(uint16_t *)frm = htole16(capinfo);
2275 	frm += 2;
2276 
2277 	frm = ieee80211_add_ssid(frm, bss->ni_essid, bss->ni_esslen);
2278 	rs = ieee80211_get_suprates(ic, bss->ni_chan);
2279 	frm = ieee80211_add_rates(frm, rs);
2280 
2281 	if (IEEE80211_IS_CHAN_FHSS(bss->ni_chan)) {
2282 		*frm++ = IEEE80211_ELEMID_FHPARMS;
2283 		*frm++ = 5;
2284 		*frm++ = bss->ni_fhdwell & 0x00ff;
2285 		*frm++ = (bss->ni_fhdwell >> 8) & 0x00ff;
2286 		*frm++ = IEEE80211_FH_CHANSET(
2287 		    ieee80211_chan2ieee(ic, bss->ni_chan));
2288 		*frm++ = IEEE80211_FH_CHANPAT(
2289 		    ieee80211_chan2ieee(ic, bss->ni_chan));
2290 		*frm++ = bss->ni_fhindex;
2291 	} else {
2292 		*frm++ = IEEE80211_ELEMID_DSPARMS;
2293 		*frm++ = 1;
2294 		*frm++ = ieee80211_chan2ieee(ic, bss->ni_chan);
2295 	}
2296 
2297 	if (vap->iv_opmode == IEEE80211_M_IBSS) {
2298 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
2299 		*frm++ = 2;
2300 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
2301 	}
2302 	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
2303 	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
2304 		frm = ieee80211_add_countryie(frm, ic);
2305 	if (vap->iv_flags & IEEE80211_F_DOTH) {
2306 		if (IEEE80211_IS_CHAN_5GHZ(bss->ni_chan))
2307 			frm = ieee80211_add_powerconstraint(frm, vap);
2308 		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
2309 			frm = ieee80211_add_csa(frm, vap);
2310 	}
2311 	if (IEEE80211_IS_CHAN_ANYG(bss->ni_chan))
2312 		frm = ieee80211_add_erp(frm, ic);
2313 	frm = ieee80211_add_xrates(frm, rs);
2314 	if (vap->iv_flags & IEEE80211_F_WPA2) {
2315 		if (vap->iv_rsn_ie != NULL)
2316 			frm = add_ie(frm, vap->iv_rsn_ie);
2317 		/* XXX else complain? */
2318 	}
2319 	/*
2320 	 * NB: legacy 11b clients do not get certain ie's.
2321 	 *     The caller identifies such clients by passing
2322 	 *     a token in legacy to us.  Could expand this to be
2323 	 *     any legacy client for stuff like HT ie's.
2324 	 */
2325 	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
2326 	    legacy != IEEE80211_SEND_LEGACY_11B) {
2327 		frm = ieee80211_add_htcap(frm, bss);
2328 		frm = ieee80211_add_htinfo(frm, bss);
2329 	}
2330 	if (vap->iv_flags & IEEE80211_F_WPA1) {
2331 		if (vap->iv_wpa_ie != NULL)
2332 			frm = add_ie(frm, vap->iv_wpa_ie);
2333 		/* XXX else complain? */
2334 	}
2335 	if (vap->iv_flags & IEEE80211_F_WME)
2336 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2337 	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
2338 	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) &&
2339 	    legacy != IEEE80211_SEND_LEGACY_11B) {
2340 		frm = ieee80211_add_htcap_vendor(frm, bss);
2341 		frm = ieee80211_add_htinfo_vendor(frm, bss);
2342 	}
2343 #ifdef IEEE80211_SUPPORT_SUPERG
2344 	if ((vap->iv_flags & IEEE80211_F_ATHEROS) &&
2345 	    legacy != IEEE80211_SEND_LEGACY_11B)
2346 		frm = ieee80211_add_athcaps(frm, bss);
2347 #endif
2348 	if (vap->iv_appie_proberesp != NULL)
2349 		frm = add_appie(frm, vap->iv_appie_proberesp);
2350 #ifdef IEEE80211_SUPPORT_MESH
2351 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
2352 		frm = ieee80211_add_meshid(frm, vap);
2353 		frm = ieee80211_add_meshconf(frm, vap);
2354 	}
2355 #endif
2356 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2357 
2358 	return m;
2359 }
2360 
2361 /*
2362  * Send a probe response frame to the specified mac address.
2363  * This does not go through the normal mgt frame api so we
2364  * can specify the destination address and re-use the bss node
2365  * for the sta reference.
2366  */
2367 int
2368 ieee80211_send_proberesp(struct ieee80211vap *vap,
2369 	const uint8_t da[IEEE80211_ADDR_LEN], int legacy)
2370 {
2371 	struct ieee80211_node *bss = vap->iv_bss;
2372 	struct ieee80211com *ic = vap->iv_ic;
2373 	struct ieee80211_frame *wh;
2374 	struct mbuf *m;
2375 
2376 	if (vap->iv_state == IEEE80211_S_CAC) {
2377 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, bss,
2378 		    "block %s frame in CAC state", "probe response");
2379 		vap->iv_stats.is_tx_badstate++;
2380 		return EIO;		/* XXX */
2381 	}
2382 
2383 	/*
2384 	 * Hold a reference on the node so it doesn't go away until after
2385 	 * the xmit is complete all the way in the driver.  On error we
2386 	 * will remove our reference.
2387 	 */
2388 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2389 	    "ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
2390 	    __func__, __LINE__, bss, ether_sprintf(bss->ni_macaddr),
2391 	    ieee80211_node_refcnt(bss)+1);
2392 	ieee80211_ref_node(bss);
2393 
2394 	m = ieee80211_alloc_proberesp(bss, legacy);
2395 	if (m == NULL) {
2396 		ieee80211_free_node(bss);
2397 		return ENOMEM;
2398 	}
2399 
2400 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
2401 	KASSERT(m != NULL, ("no room for header"));
2402 
2403 	wh = mtod(m, struct ieee80211_frame *);
2404 	ieee80211_send_setup(bss, m,
2405 	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP,
2406 	     IEEE80211_NONQOS_TID, vap->iv_myaddr, da, bss->ni_bssid);
2407 	/* XXX power management? */
2408 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
2409 
2410 	M_WME_SETAC(m, WME_AC_BE);
2411 
2412 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
2413 	    "send probe resp on channel %u to %s%s\n",
2414 	    ieee80211_chan2ieee(ic, ic->ic_curchan), ether_sprintf(da),
2415 	    legacy ? " <legacy>" : "");
2416 	IEEE80211_NODE_STAT(bss, tx_mgmt);
2417 
2418 	return ic->ic_raw_xmit(bss, m, NULL);
2419 }
2420 
2421 /*
2422  * Allocate and build a RTS (Request To Send) control frame.
2423  */
2424 struct mbuf *
2425 ieee80211_alloc_rts(struct ieee80211com *ic,
2426 	const uint8_t ra[IEEE80211_ADDR_LEN],
2427 	const uint8_t ta[IEEE80211_ADDR_LEN],
2428 	uint16_t dur)
2429 {
2430 	struct ieee80211_frame_rts *rts;
2431 	struct mbuf *m;
2432 
2433 	/* XXX honor ic_headroom */
2434 	m = m_gethdr(M_DONTWAIT, MT_DATA);
2435 	if (m != NULL) {
2436 		rts = mtod(m, struct ieee80211_frame_rts *);
2437 		rts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2438 			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_RTS;
2439 		rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2440 		*(u_int16_t *)rts->i_dur = htole16(dur);
2441 		IEEE80211_ADDR_COPY(rts->i_ra, ra);
2442 		IEEE80211_ADDR_COPY(rts->i_ta, ta);
2443 
2444 		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_rts);
2445 	}
2446 	return m;
2447 }
2448 
2449 /*
2450  * Allocate and build a CTS (Clear To Send) control frame.
2451  */
2452 struct mbuf *
2453 ieee80211_alloc_cts(struct ieee80211com *ic,
2454 	const uint8_t ra[IEEE80211_ADDR_LEN], uint16_t dur)
2455 {
2456 	struct ieee80211_frame_cts *cts;
2457 	struct mbuf *m;
2458 
2459 	/* XXX honor ic_headroom */
2460 	m = m_gethdr(M_DONTWAIT, MT_DATA);
2461 	if (m != NULL) {
2462 		cts = mtod(m, struct ieee80211_frame_cts *);
2463 		cts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2464 			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_CTS;
2465 		cts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2466 		*(u_int16_t *)cts->i_dur = htole16(dur);
2467 		IEEE80211_ADDR_COPY(cts->i_ra, ra);
2468 
2469 		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_cts);
2470 	}
2471 	return m;
2472 }
2473 
2474 static void
2475 ieee80211_tx_mgt_timeout(void *arg)
2476 {
2477 	struct ieee80211_node *ni = arg;
2478 	struct ieee80211vap *vap = ni->ni_vap;
2479 
2480 	if (vap->iv_state != IEEE80211_S_INIT &&
2481 	    (vap->iv_ic->ic_flags & IEEE80211_F_SCAN) == 0) {
2482 		/*
2483 		 * NB: it's safe to specify a timeout as the reason here;
2484 		 *     it'll only be used in the right state.
2485 		 */
2486 		ieee80211_new_state(vap, IEEE80211_S_SCAN,
2487 			IEEE80211_SCAN_FAIL_TIMEOUT);
2488 	}
2489 }
2490 
2491 static void
2492 ieee80211_tx_mgt_cb(struct ieee80211_node *ni, void *arg, int status)
2493 {
2494 	struct ieee80211vap *vap = ni->ni_vap;
2495 	enum ieee80211_state ostate = (enum ieee80211_state) arg;
2496 
2497 	/*
2498 	 * Frame transmit completed; arrange timer callback.  If
2499 	 * transmit was successfuly we wait for response.  Otherwise
2500 	 * we arrange an immediate callback instead of doing the
2501 	 * callback directly since we don't know what state the driver
2502 	 * is in (e.g. what locks it is holding).  This work should
2503 	 * not be too time-critical and not happen too often so the
2504 	 * added overhead is acceptable.
2505 	 *
2506 	 * XXX what happens if !acked but response shows up before callback?
2507 	 */
2508 	if (vap->iv_state == ostate)
2509 		callout_reset(&vap->iv_mgtsend,
2510 			status == 0 ? IEEE80211_TRANS_WAIT*hz : 0,
2511 			ieee80211_tx_mgt_timeout, ni);
2512 }
2513 
2514 static void
2515 ieee80211_beacon_construct(struct mbuf *m, uint8_t *frm,
2516 	struct ieee80211_beacon_offsets *bo, struct ieee80211_node *ni)
2517 {
2518 	struct ieee80211vap *vap = ni->ni_vap;
2519 	struct ieee80211com *ic = ni->ni_ic;
2520 	struct ieee80211_rateset *rs = &ni->ni_rates;
2521 	uint16_t capinfo;
2522 
2523 	/*
2524 	 * beacon frame format
2525 	 *	[8] time stamp
2526 	 *	[2] beacon interval
2527 	 *	[2] cabability information
2528 	 *	[tlv] ssid
2529 	 *	[tlv] supported rates
2530 	 *	[3] parameter set (DS)
2531 	 *	[8] CF parameter set (optional)
2532 	 *	[tlv] parameter set (IBSS/TIM)
2533 	 *	[tlv] country (optional)
2534 	 *	[3] power control (optional)
2535 	 *	[5] channel switch announcement (CSA) (optional)
2536 	 *	[tlv] extended rate phy (ERP)
2537 	 *	[tlv] extended supported rates
2538 	 *	[tlv] RSN parameters
2539 	 *	[tlv] HT capabilities
2540 	 *	[tlv] HT information
2541 	 * XXX Vendor-specific OIDs (e.g. Atheros)
2542 	 *	[tlv] WPA parameters
2543 	 *	[tlv] WME parameters
2544 	 *	[tlv] Vendor OUI HT capabilities (optional)
2545 	 *	[tlv] Vendor OUI HT information (optional)
2546 	 *	[tlv] Atheros capabilities (optional)
2547 	 *	[tlv] TDMA parameters (optional)
2548 	 *	[tlv] Mesh ID (MBSS)
2549 	 *	[tlv] Mesh Conf (MBSS)
2550 	 *	[tlv] application data (optional)
2551 	 */
2552 
2553 	memset(bo, 0, sizeof(*bo));
2554 
2555 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
2556 	frm += 8;
2557 	*(uint16_t *)frm = htole16(ni->ni_intval);
2558 	frm += 2;
2559 	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
2560 	bo->bo_caps = (uint16_t *)frm;
2561 	*(uint16_t *)frm = htole16(capinfo);
2562 	frm += 2;
2563 	*frm++ = IEEE80211_ELEMID_SSID;
2564 	if ((vap->iv_flags & IEEE80211_F_HIDESSID) == 0) {
2565 		*frm++ = ni->ni_esslen;
2566 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
2567 		frm += ni->ni_esslen;
2568 	} else
2569 		*frm++ = 0;
2570 	frm = ieee80211_add_rates(frm, rs);
2571 	if (!IEEE80211_IS_CHAN_FHSS(ni->ni_chan)) {
2572 		*frm++ = IEEE80211_ELEMID_DSPARMS;
2573 		*frm++ = 1;
2574 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2575 	}
2576 	if (ic->ic_flags & IEEE80211_F_PCF) {
2577 		bo->bo_cfp = frm;
2578 		frm = ieee80211_add_cfparms(frm, ic);
2579 	}
2580 	bo->bo_tim = frm;
2581 	if (vap->iv_opmode == IEEE80211_M_IBSS) {
2582 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
2583 		*frm++ = 2;
2584 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
2585 		bo->bo_tim_len = 0;
2586 	} else if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
2587 	    vap->iv_opmode == IEEE80211_M_MBSS) {
2588 		/* TIM IE is the same for Mesh and Hostap */
2589 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
2590 
2591 		tie->tim_ie = IEEE80211_ELEMID_TIM;
2592 		tie->tim_len = 4;	/* length */
2593 		tie->tim_count = 0;	/* DTIM count */
2594 		tie->tim_period = vap->iv_dtim_period;	/* DTIM period */
2595 		tie->tim_bitctl = 0;	/* bitmap control */
2596 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
2597 		frm += sizeof(struct ieee80211_tim_ie);
2598 		bo->bo_tim_len = 1;
2599 	}
2600 	bo->bo_tim_trailer = frm;
2601 	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
2602 	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
2603 		frm = ieee80211_add_countryie(frm, ic);
2604 	if (vap->iv_flags & IEEE80211_F_DOTH) {
2605 		if (IEEE80211_IS_CHAN_5GHZ(ni->ni_chan))
2606 			frm = ieee80211_add_powerconstraint(frm, vap);
2607 		bo->bo_csa = frm;
2608 		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
2609 			frm = ieee80211_add_csa(frm, vap);
2610 	} else
2611 		bo->bo_csa = frm;
2612 	if (IEEE80211_IS_CHAN_ANYG(ni->ni_chan)) {
2613 		bo->bo_erp = frm;
2614 		frm = ieee80211_add_erp(frm, ic);
2615 	}
2616 	frm = ieee80211_add_xrates(frm, rs);
2617 	if (vap->iv_flags & IEEE80211_F_WPA2) {
2618 		if (vap->iv_rsn_ie != NULL)
2619 			frm = add_ie(frm, vap->iv_rsn_ie);
2620 		/* XXX else complain */
2621 	}
2622 	if (IEEE80211_IS_CHAN_HT(ni->ni_chan)) {
2623 		frm = ieee80211_add_htcap(frm, ni);
2624 		bo->bo_htinfo = frm;
2625 		frm = ieee80211_add_htinfo(frm, ni);
2626 	}
2627 	if (vap->iv_flags & IEEE80211_F_WPA1) {
2628 		if (vap->iv_wpa_ie != NULL)
2629 			frm = add_ie(frm, vap->iv_wpa_ie);
2630 		/* XXX else complain */
2631 	}
2632 	if (vap->iv_flags & IEEE80211_F_WME) {
2633 		bo->bo_wme = frm;
2634 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2635 	}
2636 	if (IEEE80211_IS_CHAN_HT(ni->ni_chan) &&
2637 	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT)) {
2638 		frm = ieee80211_add_htcap_vendor(frm, ni);
2639 		frm = ieee80211_add_htinfo_vendor(frm, ni);
2640 	}
2641 #ifdef IEEE80211_SUPPORT_SUPERG
2642 	if (vap->iv_flags & IEEE80211_F_ATHEROS) {
2643 		bo->bo_ath = frm;
2644 		frm = ieee80211_add_athcaps(frm, ni);
2645 	}
2646 #endif
2647 #ifdef IEEE80211_SUPPORT_TDMA
2648 	if (vap->iv_caps & IEEE80211_C_TDMA) {
2649 		bo->bo_tdma = frm;
2650 		frm = ieee80211_add_tdma(frm, vap);
2651 	}
2652 #endif
2653 	if (vap->iv_appie_beacon != NULL) {
2654 		bo->bo_appie = frm;
2655 		bo->bo_appie_len = vap->iv_appie_beacon->ie_len;
2656 		frm = add_appie(frm, vap->iv_appie_beacon);
2657 	}
2658 #ifdef IEEE80211_SUPPORT_MESH
2659 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
2660 		frm = ieee80211_add_meshid(frm, vap);
2661 		bo->bo_meshconf = frm;
2662 		frm = ieee80211_add_meshconf(frm, vap);
2663 	}
2664 #endif
2665 	bo->bo_tim_trailer_len = frm - bo->bo_tim_trailer;
2666 	bo->bo_csa_trailer_len = frm - bo->bo_csa;
2667 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2668 }
2669 
2670 /*
2671  * Allocate a beacon frame and fillin the appropriate bits.
2672  */
2673 struct mbuf *
2674 ieee80211_beacon_alloc(struct ieee80211_node *ni,
2675 	struct ieee80211_beacon_offsets *bo)
2676 {
2677 	struct ieee80211vap *vap = ni->ni_vap;
2678 	struct ieee80211com *ic = ni->ni_ic;
2679 	struct ifnet *ifp = vap->iv_ifp;
2680 	struct ieee80211_frame *wh;
2681 	struct mbuf *m;
2682 	int pktlen;
2683 	uint8_t *frm;
2684 
2685 	/*
2686 	 * beacon frame format
2687 	 *	[8] time stamp
2688 	 *	[2] beacon interval
2689 	 *	[2] cabability information
2690 	 *	[tlv] ssid
2691 	 *	[tlv] supported rates
2692 	 *	[3] parameter set (DS)
2693 	 *	[8] CF parameter set (optional)
2694 	 *	[tlv] parameter set (IBSS/TIM)
2695 	 *	[tlv] country (optional)
2696 	 *	[3] power control (optional)
2697 	 *	[5] channel switch announcement (CSA) (optional)
2698 	 *	[tlv] extended rate phy (ERP)
2699 	 *	[tlv] extended supported rates
2700 	 *	[tlv] RSN parameters
2701 	 *	[tlv] HT capabilities
2702 	 *	[tlv] HT information
2703 	 *	[tlv] Vendor OUI HT capabilities (optional)
2704 	 *	[tlv] Vendor OUI HT information (optional)
2705 	 * XXX Vendor-specific OIDs (e.g. Atheros)
2706 	 *	[tlv] WPA parameters
2707 	 *	[tlv] WME parameters
2708 	 *	[tlv] TDMA parameters (optional)
2709 	 *	[tlv] Mesh ID (MBSS)
2710 	 *	[tlv] Mesh Conf (MBSS)
2711 	 *	[tlv] application data (optional)
2712 	 * NB: we allocate the max space required for the TIM bitmap.
2713 	 * XXX how big is this?
2714 	 */
2715 	pktlen =   8					/* time stamp */
2716 		 + sizeof(uint16_t)			/* beacon interval */
2717 		 + sizeof(uint16_t)			/* capabilities */
2718 		 + 2 + ni->ni_esslen			/* ssid */
2719 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
2720 	         + 2 + 1				/* DS parameters */
2721 		 + 2 + 6				/* CF parameters */
2722 		 + 2 + 4 + vap->iv_tim_len		/* DTIM/IBSSPARMS */
2723 		 + IEEE80211_COUNTRY_MAX_SIZE		/* country */
2724 		 + 2 + 1				/* power control */
2725 	         + sizeof(struct ieee80211_csa_ie)	/* CSA */
2726 		 + 2 + 1				/* ERP */
2727 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2728 		 + (vap->iv_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
2729 			2*sizeof(struct ieee80211_ie_wpa) : 0)
2730 		 /* XXX conditional? */
2731 		 + 4+2*sizeof(struct ieee80211_ie_htcap)/* HT caps */
2732 		 + 4+2*sizeof(struct ieee80211_ie_htinfo)/* HT info */
2733 		 + (vap->iv_caps & IEEE80211_C_WME ?	/* WME */
2734 			sizeof(struct ieee80211_wme_param) : 0)
2735 #ifdef IEEE80211_SUPPORT_SUPERG
2736 		 + sizeof(struct ieee80211_ath_ie)	/* ATH */
2737 #endif
2738 #ifdef IEEE80211_SUPPORT_TDMA
2739 		 + (vap->iv_caps & IEEE80211_C_TDMA ?	/* TDMA */
2740 			sizeof(struct ieee80211_tdma_param) : 0)
2741 #endif
2742 #ifdef IEEE80211_SUPPORT_MESH
2743 		 + 2 + ni->ni_meshidlen
2744 		 + sizeof(struct ieee80211_meshconf_ie)
2745 #endif
2746 		 + IEEE80211_MAX_APPIE
2747 		 ;
2748 	m = ieee80211_getmgtframe(&frm,
2749 		ic->ic_headroom + sizeof(struct ieee80211_frame), pktlen);
2750 	if (m == NULL) {
2751 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_ANY,
2752 			"%s: cannot get buf; size %u\n", __func__, pktlen);
2753 		vap->iv_stats.is_tx_nobuf++;
2754 		return NULL;
2755 	}
2756 	ieee80211_beacon_construct(m, frm, bo, ni);
2757 
2758 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
2759 	KASSERT(m != NULL, ("no space for 802.11 header?"));
2760 	wh = mtod(m, struct ieee80211_frame *);
2761 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
2762 	    IEEE80211_FC0_SUBTYPE_BEACON;
2763 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2764 	*(uint16_t *)wh->i_dur = 0;
2765 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
2766 	IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
2767 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
2768 	*(uint16_t *)wh->i_seq = 0;
2769 
2770 	return m;
2771 }
2772 
2773 /*
2774  * Update the dynamic parts of a beacon frame based on the current state.
2775  */
2776 int
2777 ieee80211_beacon_update(struct ieee80211_node *ni,
2778 	struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
2779 {
2780 	struct ieee80211vap *vap = ni->ni_vap;
2781 	struct ieee80211com *ic = ni->ni_ic;
2782 	int len_changed = 0;
2783 	uint16_t capinfo;
2784 
2785 	IEEE80211_LOCK(ic);
2786 	/*
2787 	 * Handle 11h channel change when we've reached the count.
2788 	 * We must recalculate the beacon frame contents to account
2789 	 * for the new channel.  Note we do this only for the first
2790 	 * vap that reaches this point; subsequent vaps just update
2791 	 * their beacon state to reflect the recalculated channel.
2792 	 */
2793 	if (isset(bo->bo_flags, IEEE80211_BEACON_CSA) &&
2794 	    vap->iv_csa_count == ic->ic_csa_count) {
2795 		vap->iv_csa_count = 0;
2796 		/*
2797 		 * Effect channel change before reconstructing the beacon
2798 		 * frame contents as many places reference ni_chan.
2799 		 */
2800 		if (ic->ic_csa_newchan != NULL)
2801 			ieee80211_csa_completeswitch(ic);
2802 		/*
2803 		 * NB: ieee80211_beacon_construct clears all pending
2804 		 * updates in bo_flags so we don't need to explicitly
2805 		 * clear IEEE80211_BEACON_CSA.
2806 		 */
2807 		ieee80211_beacon_construct(m,
2808 		    mtod(m, uint8_t*) + sizeof(struct ieee80211_frame), bo, ni);
2809 
2810 		/* XXX do WME aggressive mode processing? */
2811 		IEEE80211_UNLOCK(ic);
2812 		return 1;		/* just assume length changed */
2813 	}
2814 
2815 	/* XXX faster to recalculate entirely or just changes? */
2816 	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
2817 	*bo->bo_caps = htole16(capinfo);
2818 
2819 	if (vap->iv_flags & IEEE80211_F_WME) {
2820 		struct ieee80211_wme_state *wme = &ic->ic_wme;
2821 
2822 		/*
2823 		 * Check for agressive mode change.  When there is
2824 		 * significant high priority traffic in the BSS
2825 		 * throttle back BE traffic by using conservative
2826 		 * parameters.  Otherwise BE uses agressive params
2827 		 * to optimize performance of legacy/non-QoS traffic.
2828 		 */
2829 		if (wme->wme_flags & WME_F_AGGRMODE) {
2830 			if (wme->wme_hipri_traffic >
2831 			    wme->wme_hipri_switch_thresh) {
2832 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
2833 				    "%s: traffic %u, disable aggressive mode\n",
2834 				    __func__, wme->wme_hipri_traffic);
2835 				wme->wme_flags &= ~WME_F_AGGRMODE;
2836 				ieee80211_wme_updateparams_locked(vap);
2837 				wme->wme_hipri_traffic =
2838 					wme->wme_hipri_switch_hysteresis;
2839 			} else
2840 				wme->wme_hipri_traffic = 0;
2841 		} else {
2842 			if (wme->wme_hipri_traffic <=
2843 			    wme->wme_hipri_switch_thresh) {
2844 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
2845 				    "%s: traffic %u, enable aggressive mode\n",
2846 				    __func__, wme->wme_hipri_traffic);
2847 				wme->wme_flags |= WME_F_AGGRMODE;
2848 				ieee80211_wme_updateparams_locked(vap);
2849 				wme->wme_hipri_traffic = 0;
2850 			} else
2851 				wme->wme_hipri_traffic =
2852 					wme->wme_hipri_switch_hysteresis;
2853 		}
2854 		if (isset(bo->bo_flags, IEEE80211_BEACON_WME)) {
2855 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
2856 			clrbit(bo->bo_flags, IEEE80211_BEACON_WME);
2857 		}
2858 	}
2859 
2860 	if (isset(bo->bo_flags,  IEEE80211_BEACON_HTINFO)) {
2861 		ieee80211_ht_update_beacon(vap, bo);
2862 		clrbit(bo->bo_flags, IEEE80211_BEACON_HTINFO);
2863 	}
2864 #ifdef IEEE80211_SUPPORT_TDMA
2865 	if (vap->iv_caps & IEEE80211_C_TDMA) {
2866 		/*
2867 		 * NB: the beacon is potentially updated every TBTT.
2868 		 */
2869 		ieee80211_tdma_update_beacon(vap, bo);
2870 	}
2871 #endif
2872 #ifdef IEEE80211_SUPPORT_MESH
2873 	if (vap->iv_opmode == IEEE80211_M_MBSS)
2874 		ieee80211_mesh_update_beacon(vap, bo);
2875 #endif
2876 
2877 	if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
2878 	    vap->iv_opmode == IEEE80211_M_MBSS) {	/* NB: no IBSS support*/
2879 		struct ieee80211_tim_ie *tie =
2880 			(struct ieee80211_tim_ie *) bo->bo_tim;
2881 		if (isset(bo->bo_flags, IEEE80211_BEACON_TIM)) {
2882 			u_int timlen, timoff, i;
2883 			/*
2884 			 * ATIM/DTIM needs updating.  If it fits in the
2885 			 * current space allocated then just copy in the
2886 			 * new bits.  Otherwise we need to move any trailing
2887 			 * data to make room.  Note that we know there is
2888 			 * contiguous space because ieee80211_beacon_allocate
2889 			 * insures there is space in the mbuf to write a
2890 			 * maximal-size virtual bitmap (based on iv_max_aid).
2891 			 */
2892 			/*
2893 			 * Calculate the bitmap size and offset, copy any
2894 			 * trailer out of the way, and then copy in the
2895 			 * new bitmap and update the information element.
2896 			 * Note that the tim bitmap must contain at least
2897 			 * one byte and any offset must be even.
2898 			 */
2899 			if (vap->iv_ps_pending != 0) {
2900 				timoff = 128;		/* impossibly large */
2901 				for (i = 0; i < vap->iv_tim_len; i++)
2902 					if (vap->iv_tim_bitmap[i]) {
2903 						timoff = i &~ 1;
2904 						break;
2905 					}
2906 				KASSERT(timoff != 128, ("tim bitmap empty!"));
2907 				for (i = vap->iv_tim_len-1; i >= timoff; i--)
2908 					if (vap->iv_tim_bitmap[i])
2909 						break;
2910 				timlen = 1 + (i - timoff);
2911 			} else {
2912 				timoff = 0;
2913 				timlen = 1;
2914 			}
2915 			if (timlen != bo->bo_tim_len) {
2916 				/* copy up/down trailer */
2917 				int adjust = tie->tim_bitmap+timlen
2918 					   - bo->bo_tim_trailer;
2919 				ovbcopy(bo->bo_tim_trailer,
2920 				    bo->bo_tim_trailer+adjust,
2921 				    bo->bo_tim_trailer_len);
2922 				bo->bo_tim_trailer += adjust;
2923 				bo->bo_erp += adjust;
2924 				bo->bo_htinfo += adjust;
2925 #ifdef IEEE80211_SUPERG_SUPPORT
2926 				bo->bo_ath += adjust;
2927 #endif
2928 #ifdef IEEE80211_TDMA_SUPPORT
2929 				bo->bo_tdma += adjust;
2930 #endif
2931 #ifdef IEEE80211_MESH_SUPPORT
2932 				bo->bo_meshconf += adjust;
2933 #endif
2934 				bo->bo_appie += adjust;
2935 				bo->bo_wme += adjust;
2936 				bo->bo_csa += adjust;
2937 				bo->bo_tim_len = timlen;
2938 
2939 				/* update information element */
2940 				tie->tim_len = 3 + timlen;
2941 				tie->tim_bitctl = timoff;
2942 				len_changed = 1;
2943 			}
2944 			memcpy(tie->tim_bitmap, vap->iv_tim_bitmap + timoff,
2945 				bo->bo_tim_len);
2946 
2947 			clrbit(bo->bo_flags, IEEE80211_BEACON_TIM);
2948 
2949 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
2950 				"%s: TIM updated, pending %u, off %u, len %u\n",
2951 				__func__, vap->iv_ps_pending, timoff, timlen);
2952 		}
2953 		/* count down DTIM period */
2954 		if (tie->tim_count == 0)
2955 			tie->tim_count = tie->tim_period - 1;
2956 		else
2957 			tie->tim_count--;
2958 		/* update state for buffered multicast frames on DTIM */
2959 		if (mcast && tie->tim_count == 0)
2960 			tie->tim_bitctl |= 1;
2961 		else
2962 			tie->tim_bitctl &= ~1;
2963 		if (isset(bo->bo_flags, IEEE80211_BEACON_CSA)) {
2964 			struct ieee80211_csa_ie *csa =
2965 			    (struct ieee80211_csa_ie *) bo->bo_csa;
2966 
2967 			/*
2968 			 * Insert or update CSA ie.  If we're just starting
2969 			 * to count down to the channel switch then we need
2970 			 * to insert the CSA ie.  Otherwise we just need to
2971 			 * drop the count.  The actual change happens above
2972 			 * when the vap's count reaches the target count.
2973 			 */
2974 			if (vap->iv_csa_count == 0) {
2975 				memmove(&csa[1], csa, bo->bo_csa_trailer_len);
2976 				bo->bo_erp += sizeof(*csa);
2977 				bo->bo_htinfo += sizeof(*csa);
2978 				bo->bo_wme += sizeof(*csa);
2979 #ifdef IEEE80211_SUPERG_SUPPORT
2980 				bo->bo_ath += sizeof(*csa);
2981 #endif
2982 #ifdef IEEE80211_TDMA_SUPPORT
2983 				bo->bo_tdma += sizeof(*csa);
2984 #endif
2985 #ifdef IEEE80211_MESH_SUPPORT
2986 				bo->bo_meshconf += sizeof(*csa);
2987 #endif
2988 				bo->bo_appie += sizeof(*csa);
2989 				bo->bo_csa_trailer_len += sizeof(*csa);
2990 				bo->bo_tim_trailer_len += sizeof(*csa);
2991 				m->m_len += sizeof(*csa);
2992 				m->m_pkthdr.len += sizeof(*csa);
2993 
2994 				ieee80211_add_csa(bo->bo_csa, vap);
2995 			} else
2996 				csa->csa_count--;
2997 			vap->iv_csa_count++;
2998 			/* NB: don't clear IEEE80211_BEACON_CSA */
2999 		}
3000 		if (isset(bo->bo_flags, IEEE80211_BEACON_ERP)) {
3001 			/*
3002 			 * ERP element needs updating.
3003 			 */
3004 			(void) ieee80211_add_erp(bo->bo_erp, ic);
3005 			clrbit(bo->bo_flags, IEEE80211_BEACON_ERP);
3006 		}
3007 #ifdef IEEE80211_SUPPORT_SUPERG
3008 		if (isset(bo->bo_flags,  IEEE80211_BEACON_ATH)) {
3009 			ieee80211_add_athcaps(bo->bo_ath, ni);
3010 			clrbit(bo->bo_flags, IEEE80211_BEACON_ATH);
3011 		}
3012 #endif
3013 	}
3014 	if (isset(bo->bo_flags, IEEE80211_BEACON_APPIE)) {
3015 		const struct ieee80211_appie *aie = vap->iv_appie_beacon;
3016 		int aielen;
3017 		uint8_t *frm;
3018 
3019 		aielen = 0;
3020 		if (aie != NULL)
3021 			aielen += aie->ie_len;
3022 		if (aielen != bo->bo_appie_len) {
3023 			/* copy up/down trailer */
3024 			int adjust = aielen - bo->bo_appie_len;
3025 			ovbcopy(bo->bo_tim_trailer, bo->bo_tim_trailer+adjust,
3026 				bo->bo_tim_trailer_len);
3027 			bo->bo_tim_trailer += adjust;
3028 			bo->bo_appie += adjust;
3029 			bo->bo_appie_len = aielen;
3030 
3031 			len_changed = 1;
3032 		}
3033 		frm = bo->bo_appie;
3034 		if (aie != NULL)
3035 			frm  = add_appie(frm, aie);
3036 		clrbit(bo->bo_flags, IEEE80211_BEACON_APPIE);
3037 	}
3038 	IEEE80211_UNLOCK(ic);
3039 
3040 	return len_changed;
3041 }
3042