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  * $FreeBSD: head/sys/net80211/ieee80211_output.c 198384 2009-10-23 11:13:08Z rpaulo $
27  */
28 
29 #include "opt_inet.h"
30 #include "opt_inet6.h"
31 #include "opt_wlan.h"
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/mbuf.h>
36 #include <sys/kernel.h>
37 #include <sys/endian.h>
38 
39 #include <sys/socket.h>
40 
41 #include <net/bpf.h>
42 #include <net/ethernet.h>
43 #include <net/route.h>
44 #include <net/if.h>
45 #include <net/if_llc.h>
46 #include <net/if_media.h>
47 #include <net/ifq_var.h>
48 
49 #include <netproto/802_11/ieee80211_var.h>
50 #include <netproto/802_11/ieee80211_regdomain.h>
51 #ifdef IEEE80211_SUPPORT_SUPERG
52 #include <netproto/802_11/ieee80211_superg.h>
53 #endif
54 #ifdef IEEE80211_SUPPORT_TDMA
55 #include <netproto/802_11/ieee80211_tdma.h>
56 #endif
57 #include <netproto/802_11/ieee80211_wds.h>
58 #include <netproto/802_11/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 #define	ETHER_HEADER_COPY(dst, src) \
71 	memcpy(dst, src, sizeof(struct ether_header))
72 
73 /* unalligned little endian access */
74 #define LE_WRITE_2(p, v) do {				\
75 	((uint8_t *)(p))[0] = (v) & 0xff;		\
76 	((uint8_t *)(p))[1] = ((v) >> 8) & 0xff;	\
77 } while (0)
78 #define LE_WRITE_4(p, v) do {				\
79 	((uint8_t *)(p))[0] = (v) & 0xff;		\
80 	((uint8_t *)(p))[1] = ((v) >> 8) & 0xff;	\
81 	((uint8_t *)(p))[2] = ((v) >> 16) & 0xff;	\
82 	((uint8_t *)(p))[3] = ((v) >> 24) & 0xff;	\
83 } while (0)
84 
85 static int ieee80211_fragment(struct ieee80211vap *, struct mbuf *,
86 	u_int hdrsize, u_int ciphdrsize, u_int mtu);
87 static	void ieee80211_tx_mgt_cb(struct ieee80211_node *, void *, int);
88 
89 #ifdef IEEE80211_DEBUG
90 /*
91  * Decide if an outbound management frame should be
92  * printed when debugging is enabled.  This filters some
93  * of the less interesting frames that come frequently
94  * (e.g. beacons).
95  */
96 static __inline int
97 doprint(struct ieee80211vap *vap, int subtype)
98 {
99 	switch (subtype) {
100 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
101 		return (vap->iv_opmode == IEEE80211_M_IBSS);
102 	}
103 	return 1;
104 }
105 #endif
106 
107 /*
108  * Start method for vap's.  All packets from the stack come
109  * through here.  We handle common processing of the packets
110  * before dispatching them to the underlying device.
111  */
112 void
113 ieee80211_start(struct ifnet *ifp)
114 {
115 #define	IS_DWDS(vap) \
116 	(vap->iv_opmode == IEEE80211_M_WDS && \
117 	 (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY) == 0)
118 	struct ieee80211vap *vap = ifp->if_softc;
119 	struct ieee80211com *ic = vap->iv_ic;
120 	struct ifnet *parent = ic->ic_ifp;
121 	struct ieee80211_node *ni;
122 	struct mbuf *m = NULL;
123 	struct ether_header *eh;
124 	int error;
125 
126 	/* NB: parent must be up and running */
127 	if (!IFNET_IS_UP_RUNNING(parent)) {
128 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
129 		    "%s: ignore queue, parent %s not up+running\n",
130 		    __func__, parent->if_xname);
131 		/* XXX stat */
132 		ifq_purge(&ifp->if_snd);
133 		return;
134 	}
135 	if (vap->iv_state == IEEE80211_S_SLEEP) {
136 		/*
137 		 * In power save, wakeup device for transmit.
138 		 */
139 		ieee80211_new_state(vap, IEEE80211_S_RUN, 0);
140 		ifq_purge(&ifp->if_snd);
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 		/* re-check under the com lock to avoid races */
151 		if (vap->iv_state != IEEE80211_S_RUN) {
152 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
153 			    "%s: ignore queue, in %s state\n",
154 			    __func__, ieee80211_state_name[vap->iv_state]);
155 			vap->iv_stats.is_tx_badstate++;
156 			ifp->if_flags |= IFF_OACTIVE;
157 			return;
158 		}
159 	}
160 	for (;;) {
161 		m = ifq_dequeue(&ifp->if_snd, NULL);
162 		if (m == NULL)
163 			break;
164 		/*
165 		 * Sanitize mbuf flags for net80211 use.  We cannot
166 		 * clear M_PWR_SAV or M_MORE_DATA because these may
167 		 * be set for frames that are re-submitted from the
168 		 * power save queue.
169 		 *
170 		 * NB: This must be done before ieee80211_classify as
171 		 *     it marks EAPOL in frames with M_EAPOL.
172 		 */
173 		m->m_flags &= ~(M_80211_TX - M_PWR_SAV - M_MORE_DATA);
174 		/*
175 		 * Cancel any background scan.
176 		 */
177 		if (ic->ic_flags & IEEE80211_F_SCAN)
178 			ieee80211_cancel_anyscan(vap);
179 		/*
180 		 * Find the node for the destination so we can do
181 		 * things like power save and fast frames aggregation.
182 		 *
183 		 * NB: past this point various code assumes the first
184 		 *     mbuf has the 802.3 header present (and contiguous).
185 		 */
186 		ni = NULL;
187 		if (m->m_len < sizeof(struct ether_header) &&
188 		   (m = m_pullup(m, sizeof(struct ether_header))) == NULL) {
189 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
190 			    "discard frame, %s\n", "m_pullup failed");
191 			vap->iv_stats.is_tx_nobuf++;	/* XXX */
192 			ifp->if_oerrors++;
193 			continue;
194 		}
195 		eh = mtod(m, struct ether_header *);
196 		if (ETHER_IS_MULTICAST(eh->ether_dhost)) {
197 			if (IS_DWDS(vap)) {
198 				/*
199 				 * Only unicast frames from the above go out
200 				 * DWDS vaps; multicast frames are handled by
201 				 * dispatching the frame as it comes through
202 				 * the AP vap (see below).
203 				 */
204 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_WDS,
205 				    eh->ether_dhost, "mcast", "%s", "on DWDS");
206 				vap->iv_stats.is_dwds_mcast++;
207 				m_freem(m);
208 				continue;
209 			}
210 			if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
211 				/*
212 				 * Spam DWDS vap's w/ multicast traffic.
213 				 */
214 				/* XXX only if dwds in use? */
215 				ieee80211_dwds_mcast(vap, m);
216 			}
217 		}
218 #ifdef IEEE80211_SUPPORT_MESH
219 		if (vap->iv_opmode != IEEE80211_M_MBSS) {
220 #endif
221 			ni = ieee80211_find_txnode(vap, eh->ether_dhost);
222 			if (ni == NULL) {
223 				/* NB: ieee80211_find_txnode does stat+msg */
224 				ifp->if_oerrors++;
225 				m_freem(m);
226 				continue;
227 			}
228 			if (ni->ni_associd == 0 &&
229 			    (ni->ni_flags & IEEE80211_NODE_ASSOCID)) {
230 				IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
231 				    eh->ether_dhost, NULL,
232 				    "sta not associated (type 0x%04x)",
233 				    htons(eh->ether_type));
234 				vap->iv_stats.is_tx_notassoc++;
235 				ifp->if_oerrors++;
236 				m_freem(m);
237 				ieee80211_free_node(ni);
238 				continue;
239 			}
240 #ifdef IEEE80211_SUPPORT_MESH
241 		} else {
242 			if (!IEEE80211_ADDR_EQ(eh->ether_shost, vap->iv_myaddr)) {
243 				/*
244 				 * Proxy station only if configured.
245 				 */
246 				if (!ieee80211_mesh_isproxyena(vap)) {
247 					IEEE80211_DISCARD_MAC(vap,
248 					    IEEE80211_MSG_OUTPUT |
249 						IEEE80211_MSG_MESH,
250 					    eh->ether_dhost, NULL,
251 					    "%s", "proxy not enabled");
252 					vap->iv_stats.is_mesh_notproxy++;
253 					ifp->if_oerrors++;
254 					m_freem(m);
255 					continue;
256 				}
257 				ieee80211_mesh_proxy_check(vap, eh->ether_shost);
258 			}
259 			ni = ieee80211_mesh_discover(vap, eh->ether_dhost, m);
260 			if (ni == NULL) {
261 				/*
262 				 * NB: ieee80211_mesh_discover holds/disposes
263 				 * frame (e.g. queueing on path discovery).
264 				 */
265 				ifp->if_oerrors++;
266 				continue;
267 			}
268 		}
269 #endif
270 		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
271 		    (m->m_flags & M_PWR_SAV) == 0) {
272 			/*
273 			 * Station in power save mode; pass the frame
274 			 * to the 802.11 layer and continue.  We'll get
275 			 * the frame back when the time is right.
276 			 * XXX lose WDS vap linkage?
277 			 */
278 			(void) ieee80211_pwrsave(ni, m);
279 			ieee80211_free_node(ni);
280 			continue;
281 		}
282 		/* calculate priority so drivers can find the tx queue */
283 		if (ieee80211_classify(ni, m)) {
284 			IEEE80211_DISCARD_MAC(vap, IEEE80211_MSG_OUTPUT,
285 			    eh->ether_dhost, NULL,
286 			    "%s", "classification failure");
287 			vap->iv_stats.is_tx_classify++;
288 			ifp->if_oerrors++;
289 			m_freem(m);
290 			ieee80211_free_node(ni);
291 			continue;
292 		}
293 		/*
294 		 * Stash the node pointer.  Note that we do this after
295 		 * any call to ieee80211_dwds_mcast because that code
296 		 * uses any existing value for rcvif to identify the
297 		 * interface it (might have been) received on.
298 		 */
299 		m->m_pkthdr.rcvif = (void *)ni;
300 
301 		BPF_MTAP(ifp, m);		/* 802.3 tx */
302 
303 		/*
304 		 * Check if A-MPDU tx aggregation is setup or if we
305 		 * should try to enable it.  The sta must be associated
306 		 * with HT and A-MPDU enabled for use.  When the policy
307 		 * routine decides we should enable A-MPDU we issue an
308 		 * ADDBA request and wait for a reply.  The frame being
309 		 * encapsulated will go out w/o using A-MPDU, or possibly
310 		 * it might be collected by the driver and held/retransmit.
311 		 * The default ic_ampdu_enable routine handles staggering
312 		 * ADDBA requests in case the receiver NAK's us or we are
313 		 * otherwise unable to establish a BA stream.
314 		 */
315 		if ((ni->ni_flags & IEEE80211_NODE_AMPDU_TX) &&
316 		    (vap->iv_flags_ht & IEEE80211_FHT_AMPDU_TX) &&
317 		    (m->m_flags & M_EAPOL) == 0) {
318 			const int ac = M_WME_GETAC(m);
319 			struct ieee80211_tx_ampdu *tap = &ni->ni_tx_ampdu[ac];
320 
321 			ieee80211_txampdu_count_packet(tap);
322 			if (IEEE80211_AMPDU_RUNNING(tap)) {
323 				/*
324 				 * Operational, mark frame for aggregation.
325 				 *
326 				 * XXX do tx aggregation here
327 				 */
328 				m->m_flags |= M_AMPDU_MPDU;
329 			} else if (!IEEE80211_AMPDU_REQUESTED(tap) &&
330 			    ic->ic_ampdu_enable(ni, tap)) {
331 				/*
332 				 * Not negotiated yet, request service.
333 				 */
334 				ieee80211_ampdu_request(ni, tap);
335 				/* XXX hold frame for reply? */
336 			}
337 		}
338 #ifdef IEEE80211_SUPPORT_SUPERG
339 		else if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_NODE_FF)) {
340 			m = ieee80211_ff_check(ni, m);
341 			if (m == NULL) {
342 				/* NB: any ni ref held on stageq */
343 				continue;
344 			}
345 		}
346 #endif /* IEEE80211_SUPPORT_SUPERG */
347 		if (__predict_true((vap->iv_caps & IEEE80211_C_8023ENCAP) == 0)) {
348 			/*
349 			 * Encapsulate the packet in prep for transmission.
350 			 */
351 			m = ieee80211_encap(vap, ni, m);
352 			if (m == NULL) {
353 				/* NB: stat+msg handled in ieee80211_encap */
354 				ieee80211_free_node(ni);
355 				continue;
356 			}
357 		}
358 
359 		error = ieee80211_handoff(parent, m);
360 		if (error != 0) {
361 			/* NB: IFQ_HANDOFF reclaims mbuf */
362 			ieee80211_free_node(ni);
363 		} else {
364 			ifp->if_opackets++;
365 		}
366 		ic->ic_lastdata = ticks;
367 	}
368 #undef IS_DWDS
369 }
370 
371 
372 /*
373  * 802.11 output routine. This is (currently) used only to
374  * connect bpf write calls to the 802.11 layer for injecting
375  * raw 802.11 frames.
376  */
377 int
378 ieee80211_output(struct ifnet *ifp, struct mbuf *m,
379 	struct sockaddr *dst, struct rtentry *rt)
380 {
381 #define senderr(e) do { error = (e); goto bad;} while (0)
382 	struct ieee80211_node *ni = NULL;
383 	struct ieee80211vap *vap;
384 	struct ieee80211_frame *wh;
385 	int error;
386 
387 	if (ifp->if_flags & IFF_OACTIVE) {
388 		/*
389 		 * Short-circuit requests if the vap is marked OACTIVE
390 		 * as this can happen because a packet came down through
391 		 * ieee80211_start before the vap entered RUN state in
392 		 * which case it's ok to just drop the frame.  This
393 		 * should not be necessary but callers of if_output don't
394 		 * check OACTIVE.
395 		 */
396 		senderr(ENETDOWN);
397 	}
398 	vap = ifp->if_softc;
399 	/*
400 	 * Hand to the 802.3 code if not tagged as
401 	 * a raw 802.11 frame.
402 	 */
403 	if (dst->sa_family != AF_IEEE80211)
404 		return vap->iv_output(ifp, m, dst, rt);
405 #ifdef MAC
406 	error = mac_ifnet_check_transmit(ifp, m);
407 	if (error)
408 		senderr(error);
409 #endif
410 	if (ifp->if_flags & IFF_MONITOR)
411 		senderr(ENETDOWN);
412 	if (!IFNET_IS_UP_RUNNING(ifp))
413 		senderr(ENETDOWN);
414 	if (vap->iv_state == IEEE80211_S_CAC) {
415 		IEEE80211_DPRINTF(vap,
416 		    IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
417 		    "block %s frame in CAC state\n", "raw data");
418 		vap->iv_stats.is_tx_badstate++;
419 		senderr(EIO);		/* XXX */
420 	}
421 	/* XXX bypass bridge, pfil, carp, etc. */
422 
423 	if (m->m_pkthdr.len < sizeof(struct ieee80211_frame_ack))
424 		senderr(EIO);	/* XXX */
425 	wh = mtod(m, struct ieee80211_frame *);
426 	if ((wh->i_fc[0] & IEEE80211_FC0_VERSION_MASK) !=
427 	    IEEE80211_FC0_VERSION_0)
428 		senderr(EIO);	/* XXX */
429 
430 	/* locate destination node */
431 	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
432 	case IEEE80211_FC1_DIR_NODS:
433 	case IEEE80211_FC1_DIR_FROMDS:
434 		ni = ieee80211_find_txnode(vap, wh->i_addr1);
435 		break;
436 	case IEEE80211_FC1_DIR_TODS:
437 	case IEEE80211_FC1_DIR_DSTODS:
438 		if (m->m_pkthdr.len < sizeof(struct ieee80211_frame))
439 			senderr(EIO);	/* XXX */
440 		ni = ieee80211_find_txnode(vap, wh->i_addr3);
441 		break;
442 	default:
443 		senderr(EIO);	/* XXX */
444 	}
445 	if (ni == NULL) {
446 		/*
447 		 * Permit packets w/ bpf params through regardless
448 		 * (see below about sa_len).
449 		 */
450 		if (dst->sa_len == 0)
451 			senderr(EHOSTUNREACH);
452 		ni = ieee80211_ref_node(vap->iv_bss);
453 	}
454 
455 	/*
456 	 * Sanitize mbuf for net80211 flags leaked from above.
457 	 *
458 	 * NB: This must be done before ieee80211_classify as
459 	 *     it marks EAPOL in frames with M_EAPOL.
460 	 */
461 	m->m_flags &= ~M_80211_TX;
462 
463 	/* calculate priority so drivers can find the tx queue */
464 	/* XXX assumes an 802.3 frame */
465 	if (ieee80211_classify(ni, m))
466 		senderr(EIO);		/* XXX */
467 
468 	ifp->if_opackets++;
469 	IEEE80211_NODE_STAT(ni, tx_data);
470 	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
471 		IEEE80211_NODE_STAT(ni, tx_mcast);
472 		m->m_flags |= M_MCAST;
473 	} else
474 		IEEE80211_NODE_STAT(ni, tx_ucast);
475 	/* NB: ieee80211_encap does not include 802.11 header */
476 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, m->m_pkthdr.len);
477 
478 	/*
479 	 * NB: DLT_IEEE802_11_RADIO identifies the parameters are
480 	 * present by setting the sa_len field of the sockaddr (yes,
481 	 * this is a hack).
482 	 * NB: we assume sa_data is suitably aligned to cast.
483 	 */
484 	return vap->iv_ic->ic_raw_xmit(ni, m,
485 	    (const struct ieee80211_bpf_params *)(dst->sa_len ?
486 		dst->sa_data : NULL));
487 bad:
488 	if (m != NULL)
489 		m_freem(m);
490 	if (ni != NULL)
491 		ieee80211_free_node(ni);
492 	ifp->if_oerrors++;
493 	return error;
494 #undef senderr
495 }
496 
497 /*
498  * Set the direction field and address fields of an outgoing
499  * frame.  Note this should be called early on in constructing
500  * a frame as it sets i_fc[1]; other bits can then be or'd in.
501  */
502 void
503 ieee80211_send_setup(
504 	struct ieee80211_node *ni,
505 	struct mbuf *m,
506 	int type, int tid,
507 	const uint8_t sa[IEEE80211_ADDR_LEN],
508 	const uint8_t da[IEEE80211_ADDR_LEN],
509 	const uint8_t bssid[IEEE80211_ADDR_LEN])
510 {
511 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
512 	struct ieee80211vap *vap = ni->ni_vap;
513 	struct ieee80211_frame *wh = mtod(m, struct ieee80211_frame *);
514 	ieee80211_seq seqno;
515 
516 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
517 	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
518 		switch (vap->iv_opmode) {
519 		case IEEE80211_M_STA:
520 			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
521 			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
522 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
523 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
524 			break;
525 		case IEEE80211_M_IBSS:
526 		case IEEE80211_M_AHDEMO:
527 			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
528 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
529 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
530 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
531 			break;
532 		case IEEE80211_M_HOSTAP:
533 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
534 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
535 			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
536 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
537 			break;
538 		case IEEE80211_M_WDS:
539 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
540 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
541 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
542 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
543 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
544 			break;
545 		case IEEE80211_M_MBSS:
546 #ifdef IEEE80211_SUPPORT_MESH
547 			/* XXX add support for proxied addresses */
548 			if (IEEE80211_IS_MULTICAST(da)) {
549 				wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
550 				/* XXX next hop */
551 				IEEE80211_ADDR_COPY(wh->i_addr1, da);
552 				IEEE80211_ADDR_COPY(wh->i_addr2,
553 				    vap->iv_myaddr);
554 			} else {
555 				wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
556 				IEEE80211_ADDR_COPY(wh->i_addr1, da);
557 				IEEE80211_ADDR_COPY(wh->i_addr2,
558 				    vap->iv_myaddr);
559 				IEEE80211_ADDR_COPY(wh->i_addr3, da);
560 				IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, sa);
561 			}
562 #endif
563 			break;
564 		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
565 			break;
566 		}
567 	} else {
568 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
569 		IEEE80211_ADDR_COPY(wh->i_addr1, da);
570 		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
571 #ifdef IEEE80211_SUPPORT_MESH
572 		if (vap->iv_opmode == IEEE80211_M_MBSS)
573 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
574 		else
575 #endif
576 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
577 	}
578 	*(uint16_t *)&wh->i_dur[0] = 0;
579 
580 	seqno = ni->ni_txseqs[tid]++;
581 	*(uint16_t *)&wh->i_seq[0] = htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
582 	M_SEQNO_SET(m, seqno);
583 
584 	if (IEEE80211_IS_MULTICAST(wh->i_addr1))
585 		m->m_flags |= M_MCAST;
586 #undef WH4
587 }
588 
589 /*
590  * Send a management frame to the specified node.  The node pointer
591  * must have a reference as the pointer will be passed to the driver
592  * and potentially held for a long time.  If the frame is successfully
593  * dispatched to the driver, then it is responsible for freeing the
594  * reference (and potentially free'ing up any associated storage);
595  * otherwise deal with reclaiming any reference (on error).
596  */
597 int
598 ieee80211_mgmt_output(struct ieee80211_node *ni, struct mbuf *m, int type,
599 	struct ieee80211_bpf_params *params)
600 {
601 	struct ieee80211vap *vap = ni->ni_vap;
602 	struct ieee80211com *ic = ni->ni_ic;
603 	struct ieee80211_frame *wh;
604 
605 	KASSERT(ni != NULL, ("null node"));
606 
607 	if (vap->iv_state == IEEE80211_S_CAC) {
608 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
609 		    ni, "block %s frame in CAC state",
610 			ieee80211_mgt_subtype_name[
611 			    (type & IEEE80211_FC0_SUBTYPE_MASK) >>
612 				IEEE80211_FC0_SUBTYPE_SHIFT]);
613 		vap->iv_stats.is_tx_badstate++;
614 		ieee80211_free_node(ni);
615 		m_freem(m);
616 		return EIO;		/* XXX */
617 	}
618 
619 	M_PREPEND(m, sizeof(struct ieee80211_frame), MB_DONTWAIT);
620 	if (m == NULL) {
621 		ieee80211_free_node(ni);
622 		return ENOMEM;
623 	}
624 
625 	wh = mtod(m, struct ieee80211_frame *);
626 	ieee80211_send_setup(ni, m,
627 	     IEEE80211_FC0_TYPE_MGT | type, IEEE80211_NONQOS_TID,
628 	     vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
629 	if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
630 		IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_AUTH, wh->i_addr1,
631 		    "encrypting frame (%s)", __func__);
632 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
633 	}
634 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
635 
636 	KASSERT(type != IEEE80211_FC0_SUBTYPE_PROBE_RESP, ("probe response?"));
637 	M_WME_SETAC(m, params->ibp_pri);
638 
639 #ifdef IEEE80211_DEBUG
640 	/* avoid printing too many frames */
641 	if ((ieee80211_msg_debug(vap) && doprint(vap, type)) ||
642 	    ieee80211_msg_dumppkts(vap)) {
643 		kprintf("[%6D] send %s on channel %u\n",
644 		    wh->i_addr1, ":",
645 		    ieee80211_mgt_subtype_name[
646 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
647 				IEEE80211_FC0_SUBTYPE_SHIFT],
648 		    ieee80211_chan2ieee(ic, ic->ic_curchan));
649 	}
650 #endif
651 	IEEE80211_NODE_STAT(ni, tx_mgmt);
652 
653 	return ic->ic_raw_xmit(ni, m, params);
654 }
655 
656 /*
657  * Send a null data frame to the specified node.  If the station
658  * is setup for QoS then a QoS Null Data frame is constructed.
659  * If this is a WDS station then a 4-address frame is constructed.
660  *
661  * NB: the caller is assumed to have setup a node reference
662  *     for use; this is necessary to deal with a race condition
663  *     when probing for inactive stations.  Like ieee80211_mgmt_output
664  *     we must cleanup any node reference on error;  however we
665  *     can safely just unref it as we know it will never be the
666  *     last reference to the node.
667  */
668 int
669 ieee80211_send_nulldata(struct ieee80211_node *ni)
670 {
671 	struct ieee80211vap *vap = ni->ni_vap;
672 	struct ieee80211com *ic = ni->ni_ic;
673 	struct mbuf *m;
674 	struct ieee80211_frame *wh;
675 	int hdrlen;
676 	uint8_t *frm;
677 
678 	if (vap->iv_state == IEEE80211_S_CAC) {
679 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT | IEEE80211_MSG_DOTH,
680 		    ni, "block %s frame in CAC state", "null data");
681 		ieee80211_unref_node(&ni);
682 		vap->iv_stats.is_tx_badstate++;
683 		return EIO;		/* XXX */
684 	}
685 
686 	if (ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT))
687 		hdrlen = sizeof(struct ieee80211_qosframe);
688 	else
689 		hdrlen = sizeof(struct ieee80211_frame);
690 	/* NB: only WDS vap's get 4-address frames */
691 	if (vap->iv_opmode == IEEE80211_M_WDS)
692 		hdrlen += IEEE80211_ADDR_LEN;
693 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
694 		hdrlen = roundup(hdrlen, sizeof(uint32_t));
695 
696 	m = ieee80211_getmgtframe(&frm, ic->ic_headroom + hdrlen, 0);
697 	if (m == NULL) {
698 		/* XXX debug msg */
699 		ieee80211_unref_node(&ni);
700 		vap->iv_stats.is_tx_nobuf++;
701 		return ENOMEM;
702 	}
703 	KASSERT(M_LEADINGSPACE(m) >= hdrlen,
704 	    ("leading space %zd", M_LEADINGSPACE(m)));
705 	M_PREPEND(m, hdrlen, MB_DONTWAIT);
706 	if (m == NULL) {
707 		/* NB: cannot happen */
708 		ieee80211_free_node(ni);
709 		return ENOMEM;
710 	}
711 
712 	wh = mtod(m, struct ieee80211_frame *);		/* NB: a little lie */
713 	if (ni->ni_flags & IEEE80211_NODE_QOS) {
714 		const int tid = WME_AC_TO_TID(WME_AC_BE);
715 		uint8_t *qos;
716 
717 		ieee80211_send_setup(ni, m,
718 		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_QOS_NULL,
719 		    tid, vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
720 
721 		if (vap->iv_opmode == IEEE80211_M_WDS)
722 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
723 		else
724 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
725 		qos[0] = tid & IEEE80211_QOS_TID;
726 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[WME_AC_BE].wmep_noackPolicy)
727 			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
728 		qos[1] = 0;
729 	} else {
730 		ieee80211_send_setup(ni, m,
731 		    IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
732 		    IEEE80211_NONQOS_TID,
733 		    vap->iv_myaddr, ni->ni_macaddr, ni->ni_bssid);
734 	}
735 	if (vap->iv_opmode != IEEE80211_M_WDS) {
736 		/* NB: power management bit is never sent by an AP */
737 		if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
738 		    vap->iv_opmode != IEEE80211_M_HOSTAP)
739 			wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
740 	}
741 	m->m_len = m->m_pkthdr.len = hdrlen;
742 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
743 
744 	M_WME_SETAC(m, WME_AC_BE);
745 
746 	IEEE80211_NODE_STAT(ni, tx_data);
747 
748 	IEEE80211_NOTE(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS, ni,
749 	    "send %snull data frame on channel %u, pwr mgt %s",
750 	    ni->ni_flags & IEEE80211_NODE_QOS ? "QoS " : "",
751 	    ieee80211_chan2ieee(ic, ic->ic_curchan),
752 	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");
753 
754 	return ic->ic_raw_xmit(ni, m, NULL);
755 }
756 
757 /*
758  * Assign priority to a frame based on any vlan tag assigned
759  * to the station and/or any Diffserv setting in an IP header.
760  * Finally, if an ACM policy is setup (in station mode) it's
761  * applied.
762  */
763 int
764 ieee80211_classify(struct ieee80211_node *ni, struct mbuf *m)
765 {
766 	const struct ether_header *eh = mtod(m, struct ether_header *);
767 	int v_wme_ac, d_wme_ac, ac;
768 
769 	/*
770 	 * Always promote PAE/EAPOL frames to high priority.
771 	 */
772 	if (eh->ether_type == htons(ETHERTYPE_PAE)) {
773 		/* NB: mark so others don't need to check header */
774 		m->m_flags |= M_EAPOL;
775 		ac = WME_AC_VO;
776 		goto done;
777 	}
778 	/*
779 	 * Non-qos traffic goes to BE.
780 	 */
781 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
782 		ac = WME_AC_BE;
783 		goto done;
784 	}
785 
786 	/*
787 	 * If node has a vlan tag then all traffic
788 	 * to it must have a matching tag.
789 	 */
790 	v_wme_ac = 0;
791 	if (ni->ni_vlan != 0) {
792 		 if ((m->m_flags & M_VLANTAG) == 0) {
793 			IEEE80211_NODE_STAT(ni, tx_novlantag);
794 			return 1;
795 		}
796 #ifdef __FreeBSD__
797 		if (EVL_VLANOFTAG(m->m_pkthdr.ether_vlantag) !=
798 		    EVL_VLANOFTAG(ni->ni_vlan)) {
799 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
800 			return 1;
801 		}
802 		/* map vlan priority to AC */
803 		v_wme_ac = TID_TO_WME_AC(EVL_PRIOFTAG(ni->ni_vlan));
804 #endif
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 	struct mbuf *mnew = NULL;
884 	int needed_space = vap->iv_ic->ic_headroom + hdrsize;
885 
886 	if (key != NULL) {
887 		/* XXX belongs in crypto code? */
888 		needed_space += key->wk_cipher->ic_header;
889 		/* XXX frags */
890 		/*
891 		 * When crypto is being done in the host we must insure
892 		 * the data are writable for the cipher routines; clone
893 		 * a writable mbuf chain.
894 		 * XXX handle SWMIC specially
895 		 */
896 		if (key->wk_flags & (IEEE80211_KEY_SWENCRYPT|IEEE80211_KEY_SWENMIC)) {
897 			mnew = m_dup(m, MB_DONTWAIT);
898 			if (m == NULL) {
899 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
900 				    "%s: cannot get writable mbuf\n", __func__);
901 				vap->iv_stats.is_tx_nobuf++; /* XXX new stat */
902 				return NULL;
903 			}
904 			m_freem(m);
905 			m = mnew;
906 		}
907 	}
908 	/*
909 	 * We know we are called just before stripping an Ethernet
910 	 * header and prepending an LLC header.  This means we know
911 	 * there will be
912 	 *	sizeof(struct ether_header) - sizeof(struct llc)
913 	 * bytes recovered to which we need additional space for the
914 	 * 802.11 header and any crypto header.
915 	 */
916 	/* XXX check trailing space and copy instead? */
917 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
918 		struct mbuf *n = m_gethdr(MB_DONTWAIT, m->m_type);
919 		if (n == NULL) {
920 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_OUTPUT,
921 			    "%s: cannot expand storage\n", __func__);
922 			vap->iv_stats.is_tx_nobuf++;
923 			m_freem(m);
924 			return NULL;
925 		}
926 		KASSERT(needed_space <= MHLEN,
927 		    ("not enough room, need %u got %zu", needed_space, MHLEN));
928 		/*
929 		 * Setup new mbuf to have leading space to prepend the
930 		 * 802.11 header and any crypto header bits that are
931 		 * required (the latter are added when the driver calls
932 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
933 		 */
934 		/* NB: must be first 'cuz it clobbers m_data */
935 		m_move_pkthdr(n, m);
936 		n->m_len = 0;			/* NB: m_gethdr does not set */
937 		n->m_data += needed_space;
938 		/*
939 		 * Pull up Ethernet header to create the expected layout.
940 		 * We could use m_pullup but that's overkill (i.e. we don't
941 		 * need the actual data) and it cannot fail so do it inline
942 		 * for speed.
943 		 */
944 		/* NB: struct ether_header is known to be contiguous */
945 		n->m_len += sizeof(struct ether_header);
946 		m->m_len -= sizeof(struct ether_header);
947 		m->m_data += sizeof(struct ether_header);
948 		/*
949 		 * Replace the head of the chain.
950 		 */
951 		n->m_next = m;
952 		m = n;
953 	}
954 	return m;
955 #undef TO_BE_RECLAIMED
956 }
957 
958 /*
959  * Return the transmit key to use in sending a unicast frame.
960  * If a unicast key is set we use that.  When no unicast key is set
961  * we fall back to the default transmit key.
962  */
963 static __inline struct ieee80211_key *
964 ieee80211_crypto_getucastkey(struct ieee80211vap *vap,
965 	struct ieee80211_node *ni)
966 {
967 	if (IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)) {
968 		if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
969 		    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
970 			return NULL;
971 		return &vap->iv_nw_keys[vap->iv_def_txkey];
972 	} else {
973 		return &ni->ni_ucastkey;
974 	}
975 }
976 
977 /*
978  * Return the transmit key to use in sending a multicast frame.
979  * Multicast traffic always uses the group key which is installed as
980  * the default tx key.
981  */
982 static __inline struct ieee80211_key *
983 ieee80211_crypto_getmcastkey(struct ieee80211vap *vap,
984 	struct ieee80211_node *ni)
985 {
986 	if (vap->iv_def_txkey == IEEE80211_KEYIX_NONE ||
987 	    IEEE80211_KEY_UNDEFINED(&vap->iv_nw_keys[vap->iv_def_txkey]))
988 		return NULL;
989 	return &vap->iv_nw_keys[vap->iv_def_txkey];
990 }
991 
992 /*
993  * Encapsulate an outbound data frame.  The mbuf chain is updated.
994  * If an error is encountered NULL is returned.  The caller is required
995  * to provide a node reference and pullup the ethernet header in the
996  * first mbuf.
997  *
998  * NB: Packet is assumed to be processed by ieee80211_classify which
999  *     marked EAPOL frames w/ M_EAPOL.
1000  */
1001 struct mbuf *
1002 ieee80211_encap(struct ieee80211vap *vap, struct ieee80211_node *ni,
1003     struct mbuf *m)
1004 {
1005 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)(wh))
1006 	struct ieee80211com *ic = ni->ni_ic;
1007 #ifdef IEEE80211_SUPPORT_MESH
1008 	struct ieee80211_mesh_state *ms = vap->iv_mesh;
1009 	struct ieee80211_meshcntl_ae10 *mc;
1010 #endif
1011 	struct ether_header eh;
1012 	struct ieee80211_frame *wh;
1013 	struct ieee80211_key *key;
1014 	struct llc *llc;
1015 	int hdrsize, hdrspace, datalen, addqos, txfrag, is4addr;
1016 	ieee80211_seq seqno;
1017 	int meshhdrsize, meshae;
1018 	uint8_t *qos;
1019 
1020 	/*
1021 	 * Copy existing Ethernet header to a safe place.  The
1022 	 * rest of the code assumes it's ok to strip it when
1023 	 * reorganizing state for the final encapsulation.
1024 	 */
1025 	KASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
1026 	ETHER_HEADER_COPY(&eh, mtod(m, caddr_t));
1027 
1028 	/*
1029 	 * Insure space for additional headers.  First identify
1030 	 * transmit key to use in calculating any buffer adjustments
1031 	 * required.  This is also used below to do privacy
1032 	 * encapsulation work.  Then calculate the 802.11 header
1033 	 * size and any padding required by the driver.
1034 	 *
1035 	 * Note key may be NULL if we fall back to the default
1036 	 * transmit key and that is not set.  In that case the
1037 	 * buffer may not be expanded as needed by the cipher
1038 	 * routines, but they will/should discard it.
1039 	 */
1040 	if (vap->iv_flags & IEEE80211_F_PRIVACY) {
1041 		if (vap->iv_opmode == IEEE80211_M_STA ||
1042 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost) ||
1043 		    (vap->iv_opmode == IEEE80211_M_WDS &&
1044 		     (vap->iv_flags_ext & IEEE80211_FEXT_WDSLEGACY)))
1045 			key = ieee80211_crypto_getucastkey(vap, ni);
1046 		else
1047 			key = ieee80211_crypto_getmcastkey(vap, ni);
1048 		if (key == NULL && (m->m_flags & M_EAPOL) == 0) {
1049 			IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_CRYPTO,
1050 			    eh.ether_dhost,
1051 			    "no default transmit key (%s) deftxkey %u",
1052 			    __func__, vap->iv_def_txkey);
1053 			vap->iv_stats.is_tx_nodefkey++;
1054 			goto bad;
1055 		}
1056 	} else
1057 		key = NULL;
1058 	/*
1059 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
1060 	 * frames so suppress use.  This may be an issue if other
1061 	 * ap's require all data frames to be QoS-encapsulated
1062 	 * once negotiated in which case we'll need to make this
1063 	 * configurable.
1064 	 */
1065 	addqos = (ni->ni_flags & (IEEE80211_NODE_QOS|IEEE80211_NODE_HT)) &&
1066 		 (m->m_flags & M_EAPOL) == 0;
1067 	if (addqos)
1068 		hdrsize = sizeof(struct ieee80211_qosframe);
1069 	else
1070 		hdrsize = sizeof(struct ieee80211_frame);
1071 #ifdef IEEE80211_SUPPORT_MESH
1072 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
1073 		/*
1074 		 * Mesh data frames are encapsulated according to the
1075 		 * rules of Section 11B.8.5 (p.139 of D3.0 spec).
1076 		 * o Group Addressed data (aka multicast) originating
1077 		 *   at the local sta are sent w/ 3-address format and
1078 		 *   address extension mode 00
1079 		 * o Individually Addressed data (aka unicast) originating
1080 		 *   at the local sta are sent w/ 4-address format and
1081 		 *   address extension mode 00
1082 		 * o Group Addressed data forwarded from a non-mesh sta are
1083 		 *   sent w/ 3-address format and address extension mode 01
1084 		 * o Individually Address data from another sta are sent
1085 		 *   w/ 4-address format and address extension mode 10
1086 		 */
1087 		is4addr = 0;		/* NB: don't use, disable */
1088 		if (!IEEE80211_IS_MULTICAST(eh.ether_dhost))
1089 			hdrsize += IEEE80211_ADDR_LEN;	/* unicast are 4-addr */
1090 		meshhdrsize = sizeof(struct ieee80211_meshcntl);
1091 		/* XXX defines for AE modes */
1092 		if (IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr)) {
1093 			if (!IEEE80211_IS_MULTICAST(eh.ether_dhost))
1094 				meshae = 0;
1095 			else
1096 				meshae = 4;		/* NB: pseudo */
1097 		} else if (IEEE80211_IS_MULTICAST(eh.ether_dhost)) {
1098 			meshae = 1;
1099 			meshhdrsize += 1*IEEE80211_ADDR_LEN;
1100 		} else {
1101 			meshae = 2;
1102 			meshhdrsize += 2*IEEE80211_ADDR_LEN;
1103 		}
1104 	} else {
1105 #endif
1106 		/*
1107 		 * 4-address frames need to be generated for:
1108 		 * o packets sent through a WDS vap (IEEE80211_M_WDS)
1109 		 * o packets sent through a vap marked for relaying
1110 		 *   (e.g. a station operating with dynamic WDS)
1111 		 */
1112 		is4addr = vap->iv_opmode == IEEE80211_M_WDS ||
1113 		    ((vap->iv_flags_ext & IEEE80211_FEXT_4ADDR) &&
1114 		     !IEEE80211_ADDR_EQ(eh.ether_shost, vap->iv_myaddr));
1115 		if (is4addr)
1116 			hdrsize += IEEE80211_ADDR_LEN;
1117 		meshhdrsize = meshae = 0;
1118 #ifdef IEEE80211_SUPPORT_MESH
1119 	}
1120 #endif
1121 	/*
1122 	 * Honor driver DATAPAD requirement.
1123 	 */
1124 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
1125 		hdrspace = roundup(hdrsize, sizeof(uint32_t));
1126 	else
1127 		hdrspace = hdrsize;
1128 
1129 	if (__predict_true((m->m_flags & M_FF) == 0)) {
1130 		/*
1131 		 * Normal frame.
1132 		 */
1133 		m = ieee80211_mbuf_adjust(vap, hdrspace + meshhdrsize, key, m);
1134 		if (m == NULL) {
1135 			/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
1136 			goto bad;
1137 		}
1138 		/* NB: this could be optimized 'cuz of ieee80211_mbuf_adjust */
1139 		m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
1140 		llc = mtod(m, struct llc *);
1141 		llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
1142 		llc->llc_control = LLC_UI;
1143 		llc->llc_snap.org_code[0] = 0;
1144 		llc->llc_snap.org_code[1] = 0;
1145 		llc->llc_snap.org_code[2] = 0;
1146 		llc->llc_snap.ether_type = eh.ether_type;
1147 	} else {
1148 #ifdef IEEE80211_SUPPORT_SUPERG
1149 		/*
1150 		 * Aggregated frame.
1151 		 */
1152 		m = ieee80211_ff_encap(vap, m, hdrspace + meshhdrsize, key);
1153 		if (m == NULL)
1154 #endif
1155 			goto bad;
1156 	}
1157 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
1158 
1159 	M_PREPEND(m, hdrspace + meshhdrsize, MB_DONTWAIT);
1160 	if (m == NULL) {
1161 		vap->iv_stats.is_tx_nobuf++;
1162 		goto bad;
1163 	}
1164 	wh = mtod(m, struct ieee80211_frame *);
1165 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
1166 	*(uint16_t *)wh->i_dur = 0;
1167 	qos = NULL;	/* NB: quiet compiler */
1168 	if (is4addr) {
1169 		wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1170 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1171 		IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1172 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1173 		IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, eh.ether_shost);
1174 	} else switch (vap->iv_opmode) {
1175 	case IEEE80211_M_STA:
1176 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
1177 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
1178 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
1179 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1180 		break;
1181 	case IEEE80211_M_IBSS:
1182 	case IEEE80211_M_AHDEMO:
1183 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1184 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1185 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
1186 		/*
1187 		 * NB: always use the bssid from iv_bss as the
1188 		 *     neighbor's may be stale after an ibss merge
1189 		 */
1190 		IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_bss->ni_bssid);
1191 		break;
1192 	case IEEE80211_M_HOSTAP:
1193 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1194 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1195 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
1196 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
1197 		break;
1198 #ifdef IEEE80211_SUPPORT_MESH
1199 	case IEEE80211_M_MBSS:
1200 		/* NB: offset by hdrspace to deal with DATAPAD */
1201 		mc = (struct ieee80211_meshcntl_ae10 *)
1202 		     (mtod(m, uint8_t *) + hdrspace);
1203 		switch (meshae) {
1204 		case 0:			/* ucast, no proxy */
1205 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1206 			IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1207 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1208 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1209 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, eh.ether_shost);
1210 			mc->mc_flags = 0;
1211 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1212 			break;
1213 		case 4:			/* mcast, no proxy */
1214 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1215 			IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1216 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1217 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
1218 			mc->mc_flags = 0;		/* NB: AE is really 0 */
1219 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1220 			break;
1221 		case 1:			/* mcast, proxy */
1222 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
1223 			IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
1224 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1225 			IEEE80211_ADDR_COPY(wh->i_addr3, vap->iv_myaddr);
1226 			mc->mc_flags = 1;
1227 			IEEE80211_ADDR_COPY(mc->mc_addr4, eh.ether_shost);
1228 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1229 			break;
1230 		case 2:			/* ucast, proxy */
1231 			wh->i_fc[1] = IEEE80211_FC1_DIR_DSTODS;
1232 			IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
1233 			IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
1234 			/* XXX not right, need MeshDA */
1235 			IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
1236 			/* XXX assume are MeshSA */
1237 			IEEE80211_ADDR_COPY(WH4(wh)->i_addr4, vap->iv_myaddr);
1238 			mc->mc_flags = 2;
1239 			IEEE80211_ADDR_COPY(mc->mc_addr4, eh.ether_dhost);
1240 			IEEE80211_ADDR_COPY(mc->mc_addr5, eh.ether_shost);
1241 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1242 			break;
1243 		default:
1244 			KASSERT(0, ("meshae %d", meshae));
1245 			break;
1246 		}
1247 		mc->mc_ttl = ms->ms_ttl;
1248 		ms->ms_seq++;
1249 		LE_WRITE_4(mc->mc_seq, ms->ms_seq);
1250 		break;
1251 #endif
1252 	case IEEE80211_M_WDS:		/* NB: is4addr should always be true */
1253 	default:
1254 		goto bad;
1255 	}
1256 	if (m->m_flags & M_MORE_DATA)
1257 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
1258 	if (addqos) {
1259 		int ac, tid;
1260 
1261 		if (is4addr) {
1262 			qos = ((struct ieee80211_qosframe_addr4 *) wh)->i_qos;
1263 		/* NB: mesh case handled earlier */
1264 		} else if (vap->iv_opmode != IEEE80211_M_MBSS)
1265 			qos = ((struct ieee80211_qosframe *) wh)->i_qos;
1266 		ac = M_WME_GETAC(m);
1267 		/* map from access class/queue to 11e header priorty value */
1268 		tid = WME_AC_TO_TID(ac);
1269 		qos[0] = tid & IEEE80211_QOS_TID;
1270 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
1271 			qos[0] |= IEEE80211_QOS_ACKPOLICY_NOACK;
1272 		qos[1] = 0;
1273 		wh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
1274 
1275 		if ((m->m_flags & M_AMPDU_MPDU) == 0) {
1276 			/*
1277 			 * NB: don't assign a sequence # to potential
1278 			 * aggregates; we expect this happens at the
1279 			 * point the frame comes off any aggregation q
1280 			 * as otherwise we may introduce holes in the
1281 			 * BA sequence space and/or make window accouting
1282 			 * more difficult.
1283 			 *
1284 			 * XXX may want to control this with a driver
1285 			 * capability; this may also change when we pull
1286 			 * aggregation up into net80211
1287 			 */
1288 			seqno = ni->ni_txseqs[tid]++;
1289 			*(uint16_t *)wh->i_seq =
1290 			    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
1291 			M_SEQNO_SET(m, seqno);
1292 		}
1293 	} else {
1294 		seqno = ni->ni_txseqs[IEEE80211_NONQOS_TID]++;
1295 		*(uint16_t *)wh->i_seq =
1296 		    htole16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
1297 		M_SEQNO_SET(m, seqno);
1298 	}
1299 
1300 
1301 	/* check if xmit fragmentation is required */
1302 	txfrag = (m->m_pkthdr.len > vap->iv_fragthreshold &&
1303 	    !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
1304 	    (vap->iv_caps & IEEE80211_C_TXFRAG) &&
1305 	    (m->m_flags & (M_FF | M_AMPDU_MPDU)) == 0);
1306 	if (key != NULL) {
1307 		/*
1308 		 * IEEE 802.1X: send EAPOL frames always in the clear.
1309 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
1310 		 */
1311 		if ((m->m_flags & M_EAPOL) == 0 ||
1312 		    ((vap->iv_flags & IEEE80211_F_WPA) &&
1313 		     (vap->iv_opmode == IEEE80211_M_STA ?
1314 		      !IEEE80211_KEY_UNDEFINED(key) :
1315 		      !IEEE80211_KEY_UNDEFINED(&ni->ni_ucastkey)))) {
1316 			wh->i_fc[1] |= IEEE80211_FC1_WEP;
1317 			if (!ieee80211_crypto_enmic(vap, key, m, txfrag)) {
1318 				IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_OUTPUT,
1319 				    eh.ether_dhost,
1320 				    "%s", "enmic failed, discard frame");
1321 				vap->iv_stats.is_crypto_enmicfail++;
1322 				goto bad;
1323 			}
1324 		}
1325 	}
1326 	if (txfrag && !ieee80211_fragment(vap, m, hdrsize,
1327 	    key != NULL ? key->wk_cipher->ic_header : 0, vap->iv_fragthreshold))
1328 		goto bad;
1329 
1330 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
1331 
1332 	IEEE80211_NODE_STAT(ni, tx_data);
1333 	if (IEEE80211_IS_MULTICAST(wh->i_addr1)) {
1334 		IEEE80211_NODE_STAT(ni, tx_mcast);
1335 		m->m_flags |= M_MCAST;
1336 	} else
1337 		IEEE80211_NODE_STAT(ni, tx_ucast);
1338 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);
1339 
1340 	return m;
1341 bad:
1342 	if (m != NULL)
1343 		m_freem(m);
1344 	return NULL;
1345 #undef WH4
1346 }
1347 
1348 /*
1349  * Fragment the frame according to the specified mtu.
1350  * The size of the 802.11 header (w/o padding) is provided
1351  * so we don't need to recalculate it.  We create a new
1352  * mbuf for each fragment and chain it through m_nextpkt;
1353  * we might be able to optimize this by reusing the original
1354  * packet's mbufs but that is significantly more complicated.
1355  */
1356 static int
1357 ieee80211_fragment(struct ieee80211vap *vap, struct mbuf *m0,
1358 	u_int hdrsize, u_int ciphdrsize, u_int mtu)
1359 {
1360 	struct ieee80211_frame *wh, *whf;
1361 	struct mbuf *m, *prev, *next;
1362 	u_int totalhdrsize, fragno, fragsize, off, remainder, payload;
1363 
1364 	KASSERT(m0->m_nextpkt == NULL, ("mbuf already chained?"));
1365 	KASSERT(m0->m_pkthdr.len > mtu,
1366 		("pktlen %u mtu %u", m0->m_pkthdr.len, mtu));
1367 
1368 	wh = mtod(m0, struct ieee80211_frame *);
1369 	/* NB: mark the first frag; it will be propagated below */
1370 	wh->i_fc[1] |= IEEE80211_FC1_MORE_FRAG;
1371 	totalhdrsize = hdrsize + ciphdrsize;
1372 	fragno = 1;
1373 	off = mtu - ciphdrsize;
1374 	remainder = m0->m_pkthdr.len - off;
1375 	prev = m0;
1376 	do {
1377 		fragsize = totalhdrsize + remainder;
1378 		if (fragsize > mtu)
1379 			fragsize = mtu;
1380 		/* XXX fragsize can be >2048! */
1381 		KASSERT(fragsize < MCLBYTES,
1382 			("fragment size %u too big!", fragsize));
1383 		if (fragsize > MHLEN)
1384 			m = m_getcl(MB_DONTWAIT, MT_DATA, M_PKTHDR);
1385 		else
1386 			m = m_gethdr(MB_DONTWAIT, MT_DATA);
1387 		if (m == NULL)
1388 			goto bad;
1389 		/* leave room to prepend any cipher header */
1390 		m_align(m, fragsize - ciphdrsize);
1391 
1392 		/*
1393 		 * Form the header in the fragment.  Note that since
1394 		 * we mark the first fragment with the MORE_FRAG bit
1395 		 * it automatically is propagated to each fragment; we
1396 		 * need only clear it on the last fragment (done below).
1397 		 */
1398 		whf = mtod(m, struct ieee80211_frame *);
1399 		memcpy(whf, wh, hdrsize);
1400 		*(uint16_t *)&whf->i_seq[0] |= htole16(
1401 			(fragno & IEEE80211_SEQ_FRAG_MASK) <<
1402 				IEEE80211_SEQ_FRAG_SHIFT);
1403 		fragno++;
1404 
1405 		payload = fragsize - totalhdrsize;
1406 		/* NB: destination is known to be contiguous */
1407 		m_copydata(m0, off, payload, mtod(m, uint8_t *) + hdrsize);
1408 		m->m_len = hdrsize + payload;
1409 		m->m_pkthdr.len = hdrsize + payload;
1410 		m->m_flags |= M_FRAG;
1411 		m->m_pkthdr.rcvif = m0->m_pkthdr.rcvif;
1412 
1413 		/* chain up the fragment */
1414 		prev->m_nextpkt = m;
1415 		prev = m;
1416 
1417 		/* deduct fragment just formed */
1418 		remainder -= payload;
1419 		off += payload;
1420 	} while (remainder != 0);
1421 
1422 	/* set the last fragment */
1423 	m->m_flags |= M_LASTFRAG;
1424 	whf->i_fc[1] &= ~IEEE80211_FC1_MORE_FRAG;
1425 
1426 	/* strip first mbuf now that everything has been copied */
1427 	m_adj(m0, -(m0->m_pkthdr.len - (mtu - ciphdrsize)));
1428 	m0->m_flags |= M_FIRSTFRAG | M_FRAG;
1429 
1430 	vap->iv_stats.is_tx_fragframes++;
1431 	vap->iv_stats.is_tx_frags += fragno-1;
1432 
1433 	return 1;
1434 bad:
1435 	/* reclaim fragments but leave original frame for caller to free */
1436 	for (m = m0->m_nextpkt; m != NULL; m = next) {
1437 		next = m->m_nextpkt;
1438 		m->m_nextpkt = NULL;		/* XXX paranoid */
1439 		m_freem(m);
1440 	}
1441 	m0->m_nextpkt = NULL;
1442 	return 0;
1443 }
1444 
1445 /*
1446  * Add a supported rates element id to a frame.
1447  */
1448 uint8_t *
1449 ieee80211_add_rates(uint8_t *frm, const struct ieee80211_rateset *rs)
1450 {
1451 	int nrates;
1452 
1453 	*frm++ = IEEE80211_ELEMID_RATES;
1454 	nrates = rs->rs_nrates;
1455 	if (nrates > IEEE80211_RATE_SIZE)
1456 		nrates = IEEE80211_RATE_SIZE;
1457 	*frm++ = nrates;
1458 	memcpy(frm, rs->rs_rates, nrates);
1459 	return frm + nrates;
1460 }
1461 
1462 /*
1463  * Add an extended supported rates element id to a frame.
1464  */
1465 uint8_t *
1466 ieee80211_add_xrates(uint8_t *frm, const struct ieee80211_rateset *rs)
1467 {
1468 	/*
1469 	 * Add an extended supported rates element if operating in 11g mode.
1470 	 */
1471 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
1472 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
1473 		*frm++ = IEEE80211_ELEMID_XRATES;
1474 		*frm++ = nrates;
1475 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
1476 		frm += nrates;
1477 	}
1478 	return frm;
1479 }
1480 
1481 /*
1482  * Add an ssid element to a frame.
1483  */
1484 static uint8_t *
1485 ieee80211_add_ssid(uint8_t *frm, const uint8_t *ssid, u_int len)
1486 {
1487 	*frm++ = IEEE80211_ELEMID_SSID;
1488 	*frm++ = len;
1489 	memcpy(frm, ssid, len);
1490 	return frm + len;
1491 }
1492 
1493 /*
1494  * Add an erp element to a frame.
1495  */
1496 static uint8_t *
1497 ieee80211_add_erp(uint8_t *frm, struct ieee80211com *ic)
1498 {
1499 	uint8_t erp;
1500 
1501 	*frm++ = IEEE80211_ELEMID_ERP;
1502 	*frm++ = 1;
1503 	erp = 0;
1504 	if (ic->ic_nonerpsta != 0)
1505 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
1506 	if (ic->ic_flags & IEEE80211_F_USEPROT)
1507 		erp |= IEEE80211_ERP_USE_PROTECTION;
1508 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
1509 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
1510 	*frm++ = erp;
1511 	return frm;
1512 }
1513 
1514 /*
1515  * Add a CFParams element to a frame.
1516  */
1517 static uint8_t *
1518 ieee80211_add_cfparms(uint8_t *frm, struct ieee80211com *ic)
1519 {
1520 #define	ADDSHORT(frm, v) do {	\
1521 	LE_WRITE_2(frm, v);	\
1522 	frm += 2;		\
1523 } while (0)
1524 	*frm++ = IEEE80211_ELEMID_CFPARMS;
1525 	*frm++ = 6;
1526 	*frm++ = 0;		/* CFP count */
1527 	*frm++ = 2;		/* CFP period */
1528 	ADDSHORT(frm, 0);	/* CFP MaxDuration (TU) */
1529 	ADDSHORT(frm, 0);	/* CFP CurRemaining (TU) */
1530 	return frm;
1531 #undef ADDSHORT
1532 }
1533 
1534 static __inline uint8_t *
1535 add_appie(uint8_t *frm, const struct ieee80211_appie *ie)
1536 {
1537 	memcpy(frm, ie->ie_data, ie->ie_len);
1538 	return frm + ie->ie_len;
1539 }
1540 
1541 static __inline uint8_t *
1542 add_ie(uint8_t *frm, const uint8_t *ie)
1543 {
1544 	memcpy(frm, ie, 2 + ie[1]);
1545 	return frm + 2 + ie[1];
1546 }
1547 
1548 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
1549 /*
1550  * Add a WME information element to a frame.
1551  */
1552 static uint8_t *
1553 ieee80211_add_wme_info(uint8_t *frm, struct ieee80211_wme_state *wme)
1554 {
1555 	static const struct ieee80211_wme_info info = {
1556 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1557 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
1558 		.wme_oui	= { WME_OUI_BYTES },
1559 		.wme_type	= WME_OUI_TYPE,
1560 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
1561 		.wme_version	= WME_VERSION,
1562 		.wme_info	= 0,
1563 	};
1564 	memcpy(frm, &info, sizeof(info));
1565 	return frm + sizeof(info);
1566 }
1567 
1568 /*
1569  * Add a WME parameters element to a frame.
1570  */
1571 static uint8_t *
1572 ieee80211_add_wme_param(uint8_t *frm, struct ieee80211_wme_state *wme)
1573 {
1574 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
1575 #define	ADDSHORT(frm, v) do {	\
1576 	LE_WRITE_2(frm, v);	\
1577 	frm += 2;		\
1578 } while (0)
1579 	/* NB: this works 'cuz a param has an info at the front */
1580 	static const struct ieee80211_wme_info param = {
1581 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1582 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
1583 		.wme_oui	= { WME_OUI_BYTES },
1584 		.wme_type	= WME_OUI_TYPE,
1585 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
1586 		.wme_version	= WME_VERSION,
1587 	};
1588 	int i;
1589 
1590 	memcpy(frm, &param, sizeof(param));
1591 	frm += __offsetof(struct ieee80211_wme_info, wme_info);
1592 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
1593 	*frm++ = 0;					/* reserved field */
1594 	for (i = 0; i < WME_NUM_AC; i++) {
1595 		const struct wmeParams *ac =
1596 		       &wme->wme_bssChanParams.cap_wmeParams[i];
1597 		*frm++ = SM(i, WME_PARAM_ACI)
1598 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
1599 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
1600 		       ;
1601 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
1602 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
1603 		       ;
1604 		ADDSHORT(frm, ac->wmep_txopLimit);
1605 	}
1606 	return frm;
1607 #undef SM
1608 #undef ADDSHORT
1609 }
1610 #undef WME_OUI_BYTES
1611 
1612 /*
1613  * Add an 11h Power Constraint element to a frame.
1614  */
1615 static uint8_t *
1616 ieee80211_add_powerconstraint(uint8_t *frm, struct ieee80211vap *vap)
1617 {
1618 	const struct ieee80211_channel *c = vap->iv_bss->ni_chan;
1619 	/* XXX per-vap tx power limit? */
1620 	int8_t limit = vap->iv_ic->ic_txpowlimit / 2;
1621 
1622 	frm[0] = IEEE80211_ELEMID_PWRCNSTR;
1623 	frm[1] = 1;
1624 	frm[2] = c->ic_maxregpower > limit ?  c->ic_maxregpower - limit : 0;
1625 	return frm + 3;
1626 }
1627 
1628 /*
1629  * Add an 11h Power Capability element to a frame.
1630  */
1631 static uint8_t *
1632 ieee80211_add_powercapability(uint8_t *frm, const struct ieee80211_channel *c)
1633 {
1634 	frm[0] = IEEE80211_ELEMID_PWRCAP;
1635 	frm[1] = 2;
1636 	frm[2] = c->ic_minpower;
1637 	frm[3] = c->ic_maxpower;
1638 	return frm + 4;
1639 }
1640 
1641 /*
1642  * Add an 11h Supported Channels element to a frame.
1643  */
1644 static uint8_t *
1645 ieee80211_add_supportedchannels(uint8_t *frm, struct ieee80211com *ic)
1646 {
1647 	static const int ielen = 26;
1648 
1649 	frm[0] = IEEE80211_ELEMID_SUPPCHAN;
1650 	frm[1] = ielen;
1651 	/* XXX not correct */
1652 	memcpy(frm+2, ic->ic_chan_avail, ielen);
1653 	return frm + 2 + ielen;
1654 }
1655 
1656 /*
1657  * Add an 11h Channel Switch Announcement element to a frame.
1658  * Note that we use the per-vap CSA count to adjust the global
1659  * counter so we can use this routine to form probe response
1660  * frames and get the current count.
1661  */
1662 static uint8_t *
1663 ieee80211_add_csa(uint8_t *frm, struct ieee80211vap *vap)
1664 {
1665 	struct ieee80211com *ic = vap->iv_ic;
1666 	struct ieee80211_csa_ie *csa = (struct ieee80211_csa_ie *) frm;
1667 
1668 	csa->csa_ie = IEEE80211_ELEMID_CSA;
1669 	csa->csa_len = 3;
1670 	csa->csa_mode = 1;		/* XXX force quiet on channel */
1671 	csa->csa_newchan = ieee80211_chan2ieee(ic, ic->ic_csa_newchan);
1672 	csa->csa_count = ic->ic_csa_count - vap->iv_csa_count;
1673 	return frm + sizeof(*csa);
1674 }
1675 
1676 /*
1677  * Add an 11h country information element to a frame.
1678  */
1679 static uint8_t *
1680 ieee80211_add_countryie(uint8_t *frm, struct ieee80211com *ic)
1681 {
1682 
1683 	if (ic->ic_countryie == NULL ||
1684 	    ic->ic_countryie_chan != ic->ic_bsschan) {
1685 		/*
1686 		 * Handle lazy construction of ie.  This is done on
1687 		 * first use and after a channel change that requires
1688 		 * re-calculation.
1689 		 */
1690 		if (ic->ic_countryie != NULL)
1691 			kfree(ic->ic_countryie, M_80211_NODE_IE);
1692 		ic->ic_countryie = ieee80211_alloc_countryie(ic);
1693 		if (ic->ic_countryie == NULL)
1694 			return frm;
1695 		ic->ic_countryie_chan = ic->ic_bsschan;
1696 	}
1697 	return add_appie(frm, ic->ic_countryie);
1698 }
1699 
1700 /*
1701  * Send a probe request frame with the specified ssid
1702  * and any optional information element data.
1703  */
1704 int
1705 ieee80211_send_probereq(struct ieee80211_node *ni,
1706 	const uint8_t sa[IEEE80211_ADDR_LEN],
1707 	const uint8_t da[IEEE80211_ADDR_LEN],
1708 	const uint8_t bssid[IEEE80211_ADDR_LEN],
1709 	const uint8_t *ssid, size_t ssidlen)
1710 {
1711 	struct ieee80211vap *vap = ni->ni_vap;
1712 	struct ieee80211com *ic = ni->ni_ic;
1713 	const struct ieee80211_txparam *tp;
1714 	struct ieee80211_bpf_params params;
1715 	struct ieee80211_frame *wh;
1716 	const struct ieee80211_rateset *rs;
1717 	struct mbuf *m;
1718 	uint8_t *frm;
1719 
1720 	if (vap->iv_state == IEEE80211_S_CAC) {
1721 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, ni,
1722 		    "block %s frame in CAC state", "probe request");
1723 		vap->iv_stats.is_tx_badstate++;
1724 		return EIO;		/* XXX */
1725 	}
1726 
1727 	/*
1728 	 * Hold a reference on the node so it doesn't go away until after
1729 	 * the xmit is complete all the way in the driver.  On error we
1730 	 * will remove our reference.
1731 	 */
1732 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
1733 		"ieee80211_ref_node (%s:%u) %p<%6D> refcnt %d\n",
1734 		__func__, __LINE__,
1735 		ni, ni->ni_macaddr, ":",
1736 		ieee80211_node_refcnt(ni)+1);
1737 	ieee80211_ref_node(ni);
1738 
1739 	/*
1740 	 * prreq frame format
1741 	 *	[tlv] ssid
1742 	 *	[tlv] supported rates
1743 	 *	[tlv] RSN (optional)
1744 	 *	[tlv] extended supported rates
1745 	 *	[tlv] WPA (optional)
1746 	 *	[tlv] user-specified ie's
1747 	 */
1748 	m = ieee80211_getmgtframe(&frm,
1749 		 ic->ic_headroom + sizeof(struct ieee80211_frame),
1750 	       	 2 + IEEE80211_NWID_LEN
1751 	       + 2 + IEEE80211_RATE_SIZE
1752 	       + sizeof(struct ieee80211_ie_wpa)
1753 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1754 	       + sizeof(struct ieee80211_ie_wpa)
1755 	       + (vap->iv_appie_probereq != NULL ?
1756 		   vap->iv_appie_probereq->ie_len : 0)
1757 	);
1758 	if (m == NULL) {
1759 		vap->iv_stats.is_tx_nobuf++;
1760 		ieee80211_free_node(ni);
1761 		return ENOMEM;
1762 	}
1763 
1764 	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
1765 	rs = ieee80211_get_suprates(ic, ic->ic_curchan);
1766 	frm = ieee80211_add_rates(frm, rs);
1767 	if (vap->iv_flags & IEEE80211_F_WPA2) {
1768 		if (vap->iv_rsn_ie != NULL)
1769 			frm = add_ie(frm, vap->iv_rsn_ie);
1770 		/* XXX else complain? */
1771 	}
1772 	frm = ieee80211_add_xrates(frm, rs);
1773 	if (vap->iv_flags & IEEE80211_F_WPA1) {
1774 		if (vap->iv_wpa_ie != NULL)
1775 			frm = add_ie(frm, vap->iv_wpa_ie);
1776 		/* XXX else complain? */
1777 	}
1778 	if (vap->iv_appie_probereq != NULL)
1779 		frm = add_appie(frm, vap->iv_appie_probereq);
1780 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
1781 
1782 	KASSERT(M_LEADINGSPACE(m) >= sizeof(struct ieee80211_frame),
1783 	    ("leading space %zd", M_LEADINGSPACE(m)));
1784 	M_PREPEND(m, sizeof(struct ieee80211_frame), MB_DONTWAIT);
1785 	if (m == NULL) {
1786 		/* NB: cannot happen */
1787 		ieee80211_free_node(ni);
1788 		return ENOMEM;
1789 	}
1790 
1791 	wh = mtod(m, struct ieee80211_frame *);
1792 	ieee80211_send_setup(ni, m,
1793 	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
1794 	     IEEE80211_NONQOS_TID, sa, da, bssid);
1795 	/* XXX power management? */
1796 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
1797 
1798 	M_WME_SETAC(m, WME_AC_BE);
1799 
1800 	IEEE80211_NODE_STAT(ni, tx_probereq);
1801 	IEEE80211_NODE_STAT(ni, tx_mgmt);
1802 
1803 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
1804 	    "send probe req on channel %u bssid %6D ssid \"%.*s\"\n",
1805 	    ieee80211_chan2ieee(ic, ic->ic_curchan), bssid, ":",
1806 	    (int)ssidlen, ssid);
1807 
1808 	memset(&params, 0, sizeof(params));
1809 	params.ibp_pri = M_WME_GETAC(m);
1810 	tp = &vap->iv_txparms[ieee80211_chan2mode(ic->ic_curchan)];
1811 	params.ibp_rate0 = tp->mgmtrate;
1812 	if (IEEE80211_IS_MULTICAST(da)) {
1813 		params.ibp_flags |= IEEE80211_BPF_NOACK;
1814 		params.ibp_try0 = 1;
1815 	} else
1816 		params.ibp_try0 = tp->maxretry;
1817 	params.ibp_power = ni->ni_txpower;
1818 	return ic->ic_raw_xmit(ni, m, &params);
1819 }
1820 
1821 /*
1822  * Calculate capability information for mgt frames.
1823  */
1824 uint16_t
1825 ieee80211_getcapinfo(struct ieee80211vap *vap, struct ieee80211_channel *chan)
1826 {
1827 	struct ieee80211com *ic = vap->iv_ic;
1828 	uint16_t capinfo;
1829 
1830 	KASSERT(vap->iv_opmode != IEEE80211_M_STA, ("station mode"));
1831 
1832 	if (vap->iv_opmode == IEEE80211_M_HOSTAP)
1833 		capinfo = IEEE80211_CAPINFO_ESS;
1834 	else if (vap->iv_opmode == IEEE80211_M_IBSS)
1835 		capinfo = IEEE80211_CAPINFO_IBSS;
1836 	else
1837 		capinfo = 0;
1838 	if (vap->iv_flags & IEEE80211_F_PRIVACY)
1839 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1840 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1841 	    IEEE80211_IS_CHAN_2GHZ(chan))
1842 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1843 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1844 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1845 	if (IEEE80211_IS_CHAN_5GHZ(chan) && (vap->iv_flags & IEEE80211_F_DOTH))
1846 		capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
1847 	return capinfo;
1848 }
1849 
1850 /*
1851  * Send a management frame.  The node is for the destination (or ic_bss
1852  * when in station mode).  Nodes other than ic_bss have their reference
1853  * count bumped to reflect our use for an indeterminant time.
1854  */
1855 int
1856 ieee80211_send_mgmt(struct ieee80211_node *ni, int type, int arg)
1857 {
1858 #define	HTFLAGS (IEEE80211_NODE_HT | IEEE80211_NODE_HTCOMPAT)
1859 #define	senderr(_x, _v)	do { vap->iv_stats._v++; ret = _x; goto bad; } while (0)
1860 	struct ieee80211vap *vap = ni->ni_vap;
1861 	struct ieee80211com *ic = ni->ni_ic;
1862 	struct ieee80211_node *bss = vap->iv_bss;
1863 	struct ieee80211_bpf_params params;
1864 	struct mbuf *m;
1865 	uint8_t *frm;
1866 	uint16_t capinfo;
1867 	int has_challenge, is_shared_key, ret, status;
1868 
1869 	KASSERT(ni != NULL, ("null node"));
1870 
1871 	/*
1872 	 * Hold a reference on the node so it doesn't go away until after
1873 	 * the xmit is complete all the way in the driver.  On error we
1874 	 * will remove our reference.
1875 	 */
1876 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
1877 		"ieee80211_ref_node (%s:%u) %p<%6D> refcnt %d\n",
1878 		__func__, __LINE__,
1879 		ni, ni->ni_macaddr, ":",
1880 		ieee80211_node_refcnt(ni)+1);
1881 	ieee80211_ref_node(ni);
1882 
1883 	memset(&params, 0, sizeof(params));
1884 	switch (type) {
1885 
1886 	case IEEE80211_FC0_SUBTYPE_AUTH:
1887 		status = arg >> 16;
1888 		arg &= 0xffff;
1889 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1890 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1891 		    ni->ni_challenge != NULL);
1892 
1893 		/*
1894 		 * Deduce whether we're doing open authentication or
1895 		 * shared key authentication.  We do the latter if
1896 		 * we're in the middle of a shared key authentication
1897 		 * handshake or if we're initiating an authentication
1898 		 * request and configured to use shared key.
1899 		 */
1900 		is_shared_key = has_challenge ||
1901 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1902 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1903 		      bss->ni_authmode == IEEE80211_AUTH_SHARED);
1904 
1905 		m = ieee80211_getmgtframe(&frm,
1906 			  ic->ic_headroom + sizeof(struct ieee80211_frame),
1907 			  3 * sizeof(uint16_t)
1908 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1909 				sizeof(uint16_t)+IEEE80211_CHALLENGE_LEN : 0)
1910 		);
1911 		if (m == NULL)
1912 			senderr(ENOMEM, is_tx_nobuf);
1913 
1914 		((uint16_t *)frm)[0] =
1915 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1916 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1917 		((uint16_t *)frm)[1] = htole16(arg);	/* sequence number */
1918 		((uint16_t *)frm)[2] = htole16(status);/* status */
1919 
1920 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1921 			((uint16_t *)frm)[3] =
1922 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1923 			    IEEE80211_ELEMID_CHALLENGE);
1924 			memcpy(&((uint16_t *)frm)[4], ni->ni_challenge,
1925 			    IEEE80211_CHALLENGE_LEN);
1926 			m->m_pkthdr.len = m->m_len =
1927 				4 * sizeof(uint16_t) + IEEE80211_CHALLENGE_LEN;
1928 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1929 				IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
1930 				    "request encrypt frame (%s)", __func__);
1931 				/* mark frame for encryption */
1932 				params.ibp_flags |= IEEE80211_BPF_CRYPTO;
1933 			}
1934 		} else
1935 			m->m_pkthdr.len = m->m_len = 3 * sizeof(uint16_t);
1936 
1937 		/* XXX not right for shared key */
1938 		if (status == IEEE80211_STATUS_SUCCESS)
1939 			IEEE80211_NODE_STAT(ni, tx_auth);
1940 		else
1941 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1942 
1943 		if (vap->iv_opmode == IEEE80211_M_STA)
1944 			ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
1945 				(void *) vap->iv_state);
1946 		break;
1947 
1948 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1949 		IEEE80211_NOTE(vap, IEEE80211_MSG_AUTH, ni,
1950 		    "send station deauthenticate (reason %d)", arg);
1951 		m = ieee80211_getmgtframe(&frm,
1952 			ic->ic_headroom + sizeof(struct ieee80211_frame),
1953 			sizeof(uint16_t));
1954 		if (m == NULL)
1955 			senderr(ENOMEM, is_tx_nobuf);
1956 		*(uint16_t *)frm = htole16(arg);	/* reason */
1957 		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);
1958 
1959 		IEEE80211_NODE_STAT(ni, tx_deauth);
1960 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1961 
1962 		ieee80211_node_unauthorize(ni);		/* port closed */
1963 		break;
1964 
1965 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1966 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1967 		/*
1968 		 * asreq frame format
1969 		 *	[2] capability information
1970 		 *	[2] listen interval
1971 		 *	[6*] current AP address (reassoc only)
1972 		 *	[tlv] ssid
1973 		 *	[tlv] supported rates
1974 		 *	[tlv] extended supported rates
1975 		 *	[4] power capability (optional)
1976 		 *	[28] supported channels (optional)
1977 		 *	[tlv] HT capabilities
1978 		 *	[tlv] WME (optional)
1979 		 *	[tlv] Vendor OUI HT capabilities (optional)
1980 		 *	[tlv] Atheros capabilities (if negotiated)
1981 		 *	[tlv] AppIE's (optional)
1982 		 */
1983 		m = ieee80211_getmgtframe(&frm,
1984 			 ic->ic_headroom + sizeof(struct ieee80211_frame),
1985 			 sizeof(uint16_t)
1986 		       + sizeof(uint16_t)
1987 		       + IEEE80211_ADDR_LEN
1988 		       + 2 + IEEE80211_NWID_LEN
1989 		       + 2 + IEEE80211_RATE_SIZE
1990 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1991 		       + 4
1992 		       + 2 + 26
1993 		       + sizeof(struct ieee80211_wme_info)
1994 		       + sizeof(struct ieee80211_ie_htcap)
1995 		       + 4 + sizeof(struct ieee80211_ie_htcap)
1996 #ifdef IEEE80211_SUPPORT_SUPERG
1997 		       + sizeof(struct ieee80211_ath_ie)
1998 #endif
1999 		       + (vap->iv_appie_wpa != NULL ?
2000 				vap->iv_appie_wpa->ie_len : 0)
2001 		       + (vap->iv_appie_assocreq != NULL ?
2002 				vap->iv_appie_assocreq->ie_len : 0)
2003 		);
2004 		if (m == NULL)
2005 			senderr(ENOMEM, is_tx_nobuf);
2006 
2007 		KASSERT(vap->iv_opmode == IEEE80211_M_STA,
2008 		    ("wrong mode %u", vap->iv_opmode));
2009 		capinfo = IEEE80211_CAPINFO_ESS;
2010 		if (vap->iv_flags & IEEE80211_F_PRIVACY)
2011 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
2012 		/*
2013 		 * NB: Some 11a AP's reject the request when
2014 		 *     short premable is set.
2015 		 */
2016 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
2017 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
2018 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
2019 		if (IEEE80211_IS_CHAN_ANYG(ic->ic_curchan) &&
2020 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
2021 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
2022 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) &&
2023 		    (vap->iv_flags & IEEE80211_F_DOTH))
2024 			capinfo |= IEEE80211_CAPINFO_SPECTRUM_MGMT;
2025 		*(uint16_t *)frm = htole16(capinfo);
2026 		frm += 2;
2027 
2028 		KASSERT(bss->ni_intval != 0, ("beacon interval is zero!"));
2029 		*(uint16_t *)frm = htole16(howmany(ic->ic_lintval,
2030 						    bss->ni_intval));
2031 		frm += 2;
2032 
2033 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
2034 			IEEE80211_ADDR_COPY(frm, bss->ni_bssid);
2035 			frm += IEEE80211_ADDR_LEN;
2036 		}
2037 
2038 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
2039 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
2040 		if (vap->iv_flags & IEEE80211_F_WPA2) {
2041 			if (vap->iv_rsn_ie != NULL)
2042 				frm = add_ie(frm, vap->iv_rsn_ie);
2043 			/* XXX else complain? */
2044 		}
2045 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
2046 		if (capinfo & IEEE80211_CAPINFO_SPECTRUM_MGMT) {
2047 			frm = ieee80211_add_powercapability(frm,
2048 			    ic->ic_curchan);
2049 			frm = ieee80211_add_supportedchannels(frm, ic);
2050 		}
2051 		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
2052 		    ni->ni_ies.htcap_ie != NULL &&
2053 		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_HTCAP)
2054 			frm = ieee80211_add_htcap(frm, ni);
2055 		if (vap->iv_flags & IEEE80211_F_WPA1) {
2056 			if (vap->iv_wpa_ie != NULL)
2057 				frm = add_ie(frm, vap->iv_wpa_ie);
2058 			/* XXX else complain */
2059 		}
2060 		if ((ic->ic_flags & IEEE80211_F_WME) &&
2061 		    ni->ni_ies.wme_ie != NULL)
2062 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
2063 		if ((vap->iv_flags_ht & IEEE80211_FHT_HT) &&
2064 		    ni->ni_ies.htcap_ie != NULL &&
2065 		    ni->ni_ies.htcap_ie[0] == IEEE80211_ELEMID_VENDOR)
2066 			frm = ieee80211_add_htcap_vendor(frm, ni);
2067 #ifdef IEEE80211_SUPPORT_SUPERG
2068 		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS)) {
2069 			frm = ieee80211_add_ath(frm,
2070 				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
2071 				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
2072 				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
2073 				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
2074 		}
2075 #endif /* IEEE80211_SUPPORT_SUPERG */
2076 		if (vap->iv_appie_assocreq != NULL)
2077 			frm = add_appie(frm, vap->iv_appie_assocreq);
2078 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2079 
2080 		ieee80211_add_callback(m, ieee80211_tx_mgt_cb,
2081 			(void *) vap->iv_state);
2082 		break;
2083 
2084 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
2085 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
2086 		/*
2087 		 * asresp frame format
2088 		 *	[2] capability information
2089 		 *	[2] status
2090 		 *	[2] association ID
2091 		 *	[tlv] supported rates
2092 		 *	[tlv] extended supported rates
2093 		 *	[tlv] HT capabilities (standard, if STA enabled)
2094 		 *	[tlv] HT information (standard, if STA enabled)
2095 		 *	[tlv] WME (if configured and STA enabled)
2096 		 *	[tlv] HT capabilities (vendor OUI, if STA enabled)
2097 		 *	[tlv] HT information (vendor OUI, if STA enabled)
2098 		 *	[tlv] Atheros capabilities (if STA enabled)
2099 		 *	[tlv] AppIE's (optional)
2100 		 */
2101 		m = ieee80211_getmgtframe(&frm,
2102 			 ic->ic_headroom + sizeof(struct ieee80211_frame),
2103 			 sizeof(uint16_t)
2104 		       + sizeof(uint16_t)
2105 		       + sizeof(uint16_t)
2106 		       + 2 + IEEE80211_RATE_SIZE
2107 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2108 		       + sizeof(struct ieee80211_ie_htcap) + 4
2109 		       + sizeof(struct ieee80211_ie_htinfo) + 4
2110 		       + sizeof(struct ieee80211_wme_param)
2111 #ifdef IEEE80211_SUPPORT_SUPERG
2112 		       + sizeof(struct ieee80211_ath_ie)
2113 #endif
2114 		       + (vap->iv_appie_assocresp != NULL ?
2115 				vap->iv_appie_assocresp->ie_len : 0)
2116 		);
2117 		if (m == NULL)
2118 			senderr(ENOMEM, is_tx_nobuf);
2119 
2120 		capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
2121 		*(uint16_t *)frm = htole16(capinfo);
2122 		frm += 2;
2123 
2124 		*(uint16_t *)frm = htole16(arg);	/* status */
2125 		frm += 2;
2126 
2127 		if (arg == IEEE80211_STATUS_SUCCESS) {
2128 			*(uint16_t *)frm = htole16(ni->ni_associd);
2129 			IEEE80211_NODE_STAT(ni, tx_assoc);
2130 		} else
2131 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
2132 		frm += 2;
2133 
2134 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
2135 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
2136 		/* NB: respond according to what we received */
2137 		if ((ni->ni_flags & HTFLAGS) == IEEE80211_NODE_HT) {
2138 			frm = ieee80211_add_htcap(frm, ni);
2139 			frm = ieee80211_add_htinfo(frm, ni);
2140 		}
2141 		if ((vap->iv_flags & IEEE80211_F_WME) &&
2142 		    ni->ni_ies.wme_ie != NULL)
2143 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2144 		if ((ni->ni_flags & HTFLAGS) == HTFLAGS) {
2145 			frm = ieee80211_add_htcap_vendor(frm, ni);
2146 			frm = ieee80211_add_htinfo_vendor(frm, ni);
2147 		}
2148 #ifdef IEEE80211_SUPPORT_SUPERG
2149 		if (IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS))
2150 			frm = ieee80211_add_ath(frm,
2151 				IEEE80211_ATH_CAP(vap, ni, IEEE80211_F_ATHEROS),
2152 				((vap->iv_flags & IEEE80211_F_WPA) == 0 &&
2153 				 ni->ni_authmode != IEEE80211_AUTH_8021X) ?
2154 				vap->iv_def_txkey : IEEE80211_KEYIX_NONE);
2155 #endif /* IEEE80211_SUPPORT_SUPERG */
2156 		if (vap->iv_appie_assocresp != NULL)
2157 			frm = add_appie(frm, vap->iv_appie_assocresp);
2158 		m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2159 		break;
2160 
2161 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
2162 		IEEE80211_NOTE(vap, IEEE80211_MSG_ASSOC, ni,
2163 		    "send station disassociate (reason %d)", arg);
2164 		m = ieee80211_getmgtframe(&frm,
2165 			ic->ic_headroom + sizeof(struct ieee80211_frame),
2166 			sizeof(uint16_t));
2167 		if (m == NULL)
2168 			senderr(ENOMEM, is_tx_nobuf);
2169 		*(uint16_t *)frm = htole16(arg);	/* reason */
2170 		m->m_pkthdr.len = m->m_len = sizeof(uint16_t);
2171 
2172 		IEEE80211_NODE_STAT(ni, tx_disassoc);
2173 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
2174 		break;
2175 
2176 	default:
2177 		IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni,
2178 		    "invalid mgmt frame type %u", type);
2179 		senderr(EINVAL, is_tx_unknownmgt);
2180 		/* NOTREACHED */
2181 	}
2182 
2183 	/* NB: force non-ProbeResp frames to the highest queue */
2184 	params.ibp_pri = WME_AC_VO;
2185 	params.ibp_rate0 = bss->ni_txparms->mgmtrate;
2186 	/* NB: we know all frames are unicast */
2187 	params.ibp_try0 = bss->ni_txparms->maxretry;
2188 	params.ibp_power = bss->ni_txpower;
2189 	return ieee80211_mgmt_output(ni, m, type, &params);
2190 bad:
2191 	ieee80211_free_node(ni);
2192 	return ret;
2193 #undef senderr
2194 #undef HTFLAGS
2195 }
2196 
2197 /*
2198  * Return an mbuf with a probe response frame in it.
2199  * Space is left to prepend and 802.11 header at the
2200  * front but it's left to the caller to fill in.
2201  */
2202 struct mbuf *
2203 ieee80211_alloc_proberesp(struct ieee80211_node *bss, int legacy)
2204 {
2205 	struct ieee80211vap *vap = bss->ni_vap;
2206 	struct ieee80211com *ic = bss->ni_ic;
2207 	const struct ieee80211_rateset *rs;
2208 	struct mbuf *m;
2209 	uint16_t capinfo;
2210 	uint8_t *frm;
2211 
2212 	/*
2213 	 * probe response frame format
2214 	 *	[8] time stamp
2215 	 *	[2] beacon interval
2216 	 *	[2] cabability information
2217 	 *	[tlv] ssid
2218 	 *	[tlv] supported rates
2219 	 *	[tlv] parameter set (FH/DS)
2220 	 *	[tlv] parameter set (IBSS)
2221 	 *	[tlv] country (optional)
2222 	 *	[3] power control (optional)
2223 	 *	[5] channel switch announcement (CSA) (optional)
2224 	 *	[tlv] extended rate phy (ERP)
2225 	 *	[tlv] extended supported rates
2226 	 *	[tlv] RSN (optional)
2227 	 *	[tlv] HT capabilities
2228 	 *	[tlv] HT information
2229 	 *	[tlv] WPA (optional)
2230 	 *	[tlv] WME (optional)
2231 	 *	[tlv] Vendor OUI HT capabilities (optional)
2232 	 *	[tlv] Vendor OUI HT information (optional)
2233 	 *	[tlv] Atheros capabilities
2234 	 *	[tlv] AppIE's (optional)
2235 	 *	[tlv] Mesh ID (MBSS)
2236 	 *	[tlv] Mesh Conf (MBSS)
2237 	 */
2238 	m = ieee80211_getmgtframe(&frm,
2239 		 ic->ic_headroom + sizeof(struct ieee80211_frame),
2240 		 8
2241 	       + sizeof(uint16_t)
2242 	       + sizeof(uint16_t)
2243 	       + 2 + IEEE80211_NWID_LEN
2244 	       + 2 + IEEE80211_RATE_SIZE
2245 	       + 7	/* max(7,3) */
2246 	       + IEEE80211_COUNTRY_MAX_SIZE
2247 	       + 3
2248 	       + sizeof(struct ieee80211_csa_ie)
2249 	       + 3
2250 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2251 	       + sizeof(struct ieee80211_ie_wpa)
2252 	       + sizeof(struct ieee80211_ie_htcap)
2253 	       + sizeof(struct ieee80211_ie_htinfo)
2254 	       + sizeof(struct ieee80211_ie_wpa)
2255 	       + sizeof(struct ieee80211_wme_param)
2256 	       + 4 + sizeof(struct ieee80211_ie_htcap)
2257 	       + 4 + sizeof(struct ieee80211_ie_htinfo)
2258 #ifdef IEEE80211_SUPPORT_SUPERG
2259 	       + sizeof(struct ieee80211_ath_ie)
2260 #endif
2261 #ifdef IEEE80211_SUPPORT_MESH
2262 	       + 2 + IEEE80211_MESHID_LEN
2263 	       + sizeof(struct ieee80211_meshconf_ie)
2264 #endif
2265 	       + (vap->iv_appie_proberesp != NULL ?
2266 			vap->iv_appie_proberesp->ie_len : 0)
2267 	);
2268 	if (m == NULL) {
2269 		vap->iv_stats.is_tx_nobuf++;
2270 		return NULL;
2271 	}
2272 
2273 	memset(frm, 0, 8);	/* timestamp should be filled later */
2274 	frm += 8;
2275 	*(uint16_t *)frm = htole16(bss->ni_intval);
2276 	frm += 2;
2277 	capinfo = ieee80211_getcapinfo(vap, bss->ni_chan);
2278 	*(uint16_t *)frm = htole16(capinfo);
2279 	frm += 2;
2280 
2281 	frm = ieee80211_add_ssid(frm, bss->ni_essid, bss->ni_esslen);
2282 	rs = ieee80211_get_suprates(ic, bss->ni_chan);
2283 	frm = ieee80211_add_rates(frm, rs);
2284 
2285 	if (IEEE80211_IS_CHAN_FHSS(bss->ni_chan)) {
2286 		*frm++ = IEEE80211_ELEMID_FHPARMS;
2287 		*frm++ = 5;
2288 		*frm++ = bss->ni_fhdwell & 0x00ff;
2289 		*frm++ = (bss->ni_fhdwell >> 8) & 0x00ff;
2290 		*frm++ = IEEE80211_FH_CHANSET(
2291 		    ieee80211_chan2ieee(ic, bss->ni_chan));
2292 		*frm++ = IEEE80211_FH_CHANPAT(
2293 		    ieee80211_chan2ieee(ic, bss->ni_chan));
2294 		*frm++ = bss->ni_fhindex;
2295 	} else {
2296 		*frm++ = IEEE80211_ELEMID_DSPARMS;
2297 		*frm++ = 1;
2298 		*frm++ = ieee80211_chan2ieee(ic, bss->ni_chan);
2299 	}
2300 
2301 	if (vap->iv_opmode == IEEE80211_M_IBSS) {
2302 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
2303 		*frm++ = 2;
2304 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
2305 	}
2306 	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
2307 	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
2308 		frm = ieee80211_add_countryie(frm, ic);
2309 	if (vap->iv_flags & IEEE80211_F_DOTH) {
2310 		if (IEEE80211_IS_CHAN_5GHZ(bss->ni_chan))
2311 			frm = ieee80211_add_powerconstraint(frm, vap);
2312 		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
2313 			frm = ieee80211_add_csa(frm, vap);
2314 	}
2315 	if (IEEE80211_IS_CHAN_ANYG(bss->ni_chan))
2316 		frm = ieee80211_add_erp(frm, ic);
2317 	frm = ieee80211_add_xrates(frm, rs);
2318 	if (vap->iv_flags & IEEE80211_F_WPA2) {
2319 		if (vap->iv_rsn_ie != NULL)
2320 			frm = add_ie(frm, vap->iv_rsn_ie);
2321 		/* XXX else complain? */
2322 	}
2323 	/*
2324 	 * NB: legacy 11b clients do not get certain ie's.
2325 	 *     The caller identifies such clients by passing
2326 	 *     a token in legacy to us.  Could expand this to be
2327 	 *     any legacy client for stuff like HT ie's.
2328 	 */
2329 	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
2330 	    legacy != IEEE80211_SEND_LEGACY_11B) {
2331 		frm = ieee80211_add_htcap(frm, bss);
2332 		frm = ieee80211_add_htinfo(frm, bss);
2333 	}
2334 	if (vap->iv_flags & IEEE80211_F_WPA1) {
2335 		if (vap->iv_wpa_ie != NULL)
2336 			frm = add_ie(frm, vap->iv_wpa_ie);
2337 		/* XXX else complain? */
2338 	}
2339 	if (vap->iv_flags & IEEE80211_F_WME)
2340 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2341 	if (IEEE80211_IS_CHAN_HT(bss->ni_chan) &&
2342 	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT) &&
2343 	    legacy != IEEE80211_SEND_LEGACY_11B) {
2344 		frm = ieee80211_add_htcap_vendor(frm, bss);
2345 		frm = ieee80211_add_htinfo_vendor(frm, bss);
2346 	}
2347 #ifdef IEEE80211_SUPPORT_SUPERG
2348 	if ((vap->iv_flags & IEEE80211_F_ATHEROS) &&
2349 	    legacy != IEEE80211_SEND_LEGACY_11B)
2350 		frm = ieee80211_add_athcaps(frm, bss);
2351 #endif
2352 	if (vap->iv_appie_proberesp != NULL)
2353 		frm = add_appie(frm, vap->iv_appie_proberesp);
2354 #ifdef IEEE80211_SUPPORT_MESH
2355 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
2356 		frm = ieee80211_add_meshid(frm, vap);
2357 		frm = ieee80211_add_meshconf(frm, vap);
2358 	}
2359 #endif
2360 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2361 
2362 	return m;
2363 }
2364 
2365 /*
2366  * Send a probe response frame to the specified mac address.
2367  * This does not go through the normal mgt frame api so we
2368  * can specify the destination address and re-use the bss node
2369  * for the sta reference.
2370  */
2371 int
2372 ieee80211_send_proberesp(struct ieee80211vap *vap,
2373 	const uint8_t da[IEEE80211_ADDR_LEN], int legacy)
2374 {
2375 	struct ieee80211_node *bss = vap->iv_bss;
2376 	struct ieee80211com *ic = vap->iv_ic;
2377 	struct ieee80211_frame *wh;
2378 	struct mbuf *m;
2379 
2380 	if (vap->iv_state == IEEE80211_S_CAC) {
2381 		IEEE80211_NOTE(vap, IEEE80211_MSG_OUTPUT, bss,
2382 		    "block %s frame in CAC state", "probe response");
2383 		vap->iv_stats.is_tx_badstate++;
2384 		return EIO;		/* XXX */
2385 	}
2386 
2387 	/*
2388 	 * Hold a reference on the node so it doesn't go away until after
2389 	 * the xmit is complete all the way in the driver.  On error we
2390 	 * will remove our reference.
2391 	 */
2392 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_NODE,
2393 	    "ieee80211_ref_node (%s:%u) %p<%6D> refcnt %d\n",
2394 	    __func__, __LINE__, bss, bss->ni_macaddr, ":",
2395 	    ieee80211_node_refcnt(bss)+1);
2396 	ieee80211_ref_node(bss);
2397 
2398 	m = ieee80211_alloc_proberesp(bss, legacy);
2399 	if (m == NULL) {
2400 		ieee80211_free_node(bss);
2401 		return ENOMEM;
2402 	}
2403 
2404 	M_PREPEND(m, sizeof(struct ieee80211_frame), MB_DONTWAIT);
2405 	KASSERT(m != NULL, ("no room for header"));
2406 
2407 	wh = mtod(m, struct ieee80211_frame *);
2408 	ieee80211_send_setup(bss, m,
2409 	     IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_RESP,
2410 	     IEEE80211_NONQOS_TID, vap->iv_myaddr, da, bss->ni_bssid);
2411 	/* XXX power management? */
2412 	m->m_flags |= M_ENCAP;		/* mark encapsulated */
2413 
2414 	M_WME_SETAC(m, WME_AC_BE);
2415 
2416 	IEEE80211_DPRINTF(vap, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
2417 	    "send probe resp on channel %u to %6D%s\n",
2418 	    ieee80211_chan2ieee(ic, ic->ic_curchan), da, ":",
2419 	    legacy ? " <legacy>" : "");
2420 	IEEE80211_NODE_STAT(bss, tx_mgmt);
2421 
2422 	return ic->ic_raw_xmit(bss, m, NULL);
2423 }
2424 
2425 /*
2426  * Allocate and build a RTS (Request To Send) control frame.
2427  */
2428 struct mbuf *
2429 ieee80211_alloc_rts(struct ieee80211com *ic,
2430 	const uint8_t ra[IEEE80211_ADDR_LEN],
2431 	const uint8_t ta[IEEE80211_ADDR_LEN],
2432 	uint16_t dur)
2433 {
2434 	struct ieee80211_frame_rts *rts;
2435 	struct mbuf *m;
2436 
2437 	/* XXX honor ic_headroom */
2438 	m = m_gethdr(MB_DONTWAIT, MT_DATA);
2439 	if (m != NULL) {
2440 		rts = mtod(m, struct ieee80211_frame_rts *);
2441 		rts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2442 			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_RTS;
2443 		rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2444 		*(u_int16_t *)rts->i_dur = htole16(dur);
2445 		IEEE80211_ADDR_COPY(rts->i_ra, ra);
2446 		IEEE80211_ADDR_COPY(rts->i_ta, ta);
2447 
2448 		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_rts);
2449 	}
2450 	return m;
2451 }
2452 
2453 /*
2454  * Allocate and build a CTS (Clear To Send) control frame.
2455  */
2456 struct mbuf *
2457 ieee80211_alloc_cts(struct ieee80211com *ic,
2458 	const uint8_t ra[IEEE80211_ADDR_LEN], uint16_t dur)
2459 {
2460 	struct ieee80211_frame_cts *cts;
2461 	struct mbuf *m;
2462 
2463 	/* XXX honor ic_headroom */
2464 	m = m_gethdr(MB_DONTWAIT, MT_DATA);
2465 	if (m != NULL) {
2466 		cts = mtod(m, struct ieee80211_frame_cts *);
2467 		cts->i_fc[0] = IEEE80211_FC0_VERSION_0 |
2468 			IEEE80211_FC0_TYPE_CTL | IEEE80211_FC0_SUBTYPE_CTS;
2469 		cts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2470 		*(u_int16_t *)cts->i_dur = htole16(dur);
2471 		IEEE80211_ADDR_COPY(cts->i_ra, ra);
2472 
2473 		m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_cts);
2474 	}
2475 	return m;
2476 }
2477 
2478 static void
2479 ieee80211_tx_mgt_timeout_callout(void *arg)
2480 {
2481 	struct ieee80211_node *ni = arg;
2482 	struct ieee80211vap *vap;
2483 
2484 	wlan_serialize_enter();
2485 	vap = ni->ni_vap;
2486 	if (vap->iv_state != IEEE80211_S_INIT &&
2487 	    (vap->iv_ic->ic_flags & IEEE80211_F_SCAN) == 0) {
2488 		/*
2489 		 * NB: it's safe to specify a timeout as the reason here;
2490 		 *     it'll only be used in the right state.
2491 		 */
2492 		ieee80211_new_state(vap, IEEE80211_S_SCAN,
2493 			IEEE80211_SCAN_FAIL_TIMEOUT);
2494 	}
2495 	wlan_serialize_exit();
2496 }
2497 
2498 static void
2499 ieee80211_tx_mgt_cb(struct ieee80211_node *ni, void *arg, int status)
2500 {
2501 	struct ieee80211vap *vap = ni->ni_vap;
2502 	enum ieee80211_state ostate = (enum ieee80211_state) arg;
2503 
2504 	/*
2505 	 * Frame transmit completed; arrange timer callback.  If
2506 	 * transmit was successfuly we wait for response.  Otherwise
2507 	 * we arrange an immediate callback instead of doing the
2508 	 * callback directly since we don't know what state the driver
2509 	 * is in (e.g. what locks it is holding).  This work should
2510 	 * not be too time-critical and not happen too often so the
2511 	 * added overhead is acceptable.
2512 	 *
2513 	 * XXX what happens if !acked but response shows up before callback?
2514 	 */
2515 	if (vap->iv_state == ostate)
2516 		callout_reset(&vap->iv_mgtsend,
2517 			status == 0 ? IEEE80211_TRANS_WAIT*hz : 0,
2518 			ieee80211_tx_mgt_timeout_callout, ni);
2519 }
2520 
2521 static void
2522 ieee80211_beacon_construct(struct mbuf *m, uint8_t *frm,
2523 	struct ieee80211_beacon_offsets *bo, struct ieee80211_node *ni)
2524 {
2525 	struct ieee80211vap *vap = ni->ni_vap;
2526 	struct ieee80211com *ic = ni->ni_ic;
2527 	struct ieee80211_rateset *rs = &ni->ni_rates;
2528 	uint16_t capinfo;
2529 
2530 	/*
2531 	 * beacon frame format
2532 	 *	[8] time stamp
2533 	 *	[2] beacon interval
2534 	 *	[2] cabability information
2535 	 *	[tlv] ssid
2536 	 *	[tlv] supported rates
2537 	 *	[3] parameter set (DS)
2538 	 *	[8] CF parameter set (optional)
2539 	 *	[tlv] parameter set (IBSS/TIM)
2540 	 *	[tlv] country (optional)
2541 	 *	[3] power control (optional)
2542 	 *	[5] channel switch announcement (CSA) (optional)
2543 	 *	[tlv] extended rate phy (ERP)
2544 	 *	[tlv] extended supported rates
2545 	 *	[tlv] RSN parameters
2546 	 *	[tlv] HT capabilities
2547 	 *	[tlv] HT information
2548 	 * XXX Vendor-specific OIDs (e.g. Atheros)
2549 	 *	[tlv] WPA parameters
2550 	 *	[tlv] WME parameters
2551 	 *	[tlv] Vendor OUI HT capabilities (optional)
2552 	 *	[tlv] Vendor OUI HT information (optional)
2553 	 *	[tlv] Atheros capabilities (optional)
2554 	 *	[tlv] TDMA parameters (optional)
2555 	 *	[tlv] Mesh ID (MBSS)
2556 	 *	[tlv] Mesh Conf (MBSS)
2557 	 *	[tlv] application data (optional)
2558 	 */
2559 
2560 	memset(bo, 0, sizeof(*bo));
2561 
2562 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
2563 	frm += 8;
2564 	*(uint16_t *)frm = htole16(ni->ni_intval);
2565 	frm += 2;
2566 	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
2567 	bo->bo_caps = (uint16_t *)frm;
2568 	*(uint16_t *)frm = htole16(capinfo);
2569 	frm += 2;
2570 	*frm++ = IEEE80211_ELEMID_SSID;
2571 	if ((vap->iv_flags & IEEE80211_F_HIDESSID) == 0) {
2572 		*frm++ = ni->ni_esslen;
2573 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
2574 		frm += ni->ni_esslen;
2575 	} else
2576 		*frm++ = 0;
2577 	frm = ieee80211_add_rates(frm, rs);
2578 	if (!IEEE80211_IS_CHAN_FHSS(ni->ni_chan)) {
2579 		*frm++ = IEEE80211_ELEMID_DSPARMS;
2580 		*frm++ = 1;
2581 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
2582 	}
2583 	if (ic->ic_flags & IEEE80211_F_PCF) {
2584 		bo->bo_cfp = frm;
2585 		frm = ieee80211_add_cfparms(frm, ic);
2586 	}
2587 	bo->bo_tim = frm;
2588 	if (vap->iv_opmode == IEEE80211_M_IBSS) {
2589 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
2590 		*frm++ = 2;
2591 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
2592 		bo->bo_tim_len = 0;
2593 	} else if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
2594 	    vap->iv_opmode == IEEE80211_M_MBSS) {
2595 		/* TIM IE is the same for Mesh and Hostap */
2596 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
2597 
2598 		tie->tim_ie = IEEE80211_ELEMID_TIM;
2599 		tie->tim_len = 4;	/* length */
2600 		tie->tim_count = 0;	/* DTIM count */
2601 		tie->tim_period = vap->iv_dtim_period;	/* DTIM period */
2602 		tie->tim_bitctl = 0;	/* bitmap control */
2603 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
2604 		frm += sizeof(struct ieee80211_tim_ie);
2605 		bo->bo_tim_len = 1;
2606 	}
2607 	bo->bo_tim_trailer = frm;
2608 	if ((vap->iv_flags & IEEE80211_F_DOTH) ||
2609 	    (vap->iv_flags_ext & IEEE80211_FEXT_DOTD))
2610 		frm = ieee80211_add_countryie(frm, ic);
2611 	if (vap->iv_flags & IEEE80211_F_DOTH) {
2612 		if (IEEE80211_IS_CHAN_5GHZ(ni->ni_chan))
2613 			frm = ieee80211_add_powerconstraint(frm, vap);
2614 		bo->bo_csa = frm;
2615 		if (ic->ic_flags & IEEE80211_F_CSAPENDING)
2616 			frm = ieee80211_add_csa(frm, vap);
2617 	} else
2618 		bo->bo_csa = frm;
2619 	if (IEEE80211_IS_CHAN_ANYG(ni->ni_chan)) {
2620 		bo->bo_erp = frm;
2621 		frm = ieee80211_add_erp(frm, ic);
2622 	}
2623 	frm = ieee80211_add_xrates(frm, rs);
2624 	if (vap->iv_flags & IEEE80211_F_WPA2) {
2625 		if (vap->iv_rsn_ie != NULL)
2626 			frm = add_ie(frm, vap->iv_rsn_ie);
2627 		/* XXX else complain */
2628 	}
2629 	if (IEEE80211_IS_CHAN_HT(ni->ni_chan)) {
2630 		frm = ieee80211_add_htcap(frm, ni);
2631 		bo->bo_htinfo = frm;
2632 		frm = ieee80211_add_htinfo(frm, ni);
2633 	}
2634 	if (vap->iv_flags & IEEE80211_F_WPA1) {
2635 		if (vap->iv_wpa_ie != NULL)
2636 			frm = add_ie(frm, vap->iv_wpa_ie);
2637 		/* XXX else complain */
2638 	}
2639 	if (vap->iv_flags & IEEE80211_F_WME) {
2640 		bo->bo_wme = frm;
2641 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
2642 	}
2643 	if (IEEE80211_IS_CHAN_HT(ni->ni_chan) &&
2644 	    (vap->iv_flags_ht & IEEE80211_FHT_HTCOMPAT)) {
2645 		frm = ieee80211_add_htcap_vendor(frm, ni);
2646 		frm = ieee80211_add_htinfo_vendor(frm, ni);
2647 	}
2648 #ifdef IEEE80211_SUPPORT_SUPERG
2649 	if (vap->iv_flags & IEEE80211_F_ATHEROS) {
2650 		bo->bo_ath = frm;
2651 		frm = ieee80211_add_athcaps(frm, ni);
2652 	}
2653 #endif
2654 #ifdef IEEE80211_SUPPORT_TDMA
2655 	if (vap->iv_caps & IEEE80211_C_TDMA) {
2656 		bo->bo_tdma = frm;
2657 		frm = ieee80211_add_tdma(frm, vap);
2658 	}
2659 #endif
2660 	if (vap->iv_appie_beacon != NULL) {
2661 		bo->bo_appie = frm;
2662 		bo->bo_appie_len = vap->iv_appie_beacon->ie_len;
2663 		frm = add_appie(frm, vap->iv_appie_beacon);
2664 	}
2665 #ifdef IEEE80211_SUPPORT_MESH
2666 	if (vap->iv_opmode == IEEE80211_M_MBSS) {
2667 		frm = ieee80211_add_meshid(frm, vap);
2668 		bo->bo_meshconf = frm;
2669 		frm = ieee80211_add_meshconf(frm, vap);
2670 	}
2671 #endif
2672 	bo->bo_tim_trailer_len = frm - bo->bo_tim_trailer;
2673 	bo->bo_csa_trailer_len = frm - bo->bo_csa;
2674 	m->m_pkthdr.len = m->m_len = frm - mtod(m, uint8_t *);
2675 }
2676 
2677 /*
2678  * Allocate a beacon frame and fillin the appropriate bits.
2679  */
2680 struct mbuf *
2681 ieee80211_beacon_alloc(struct ieee80211_node *ni,
2682 	struct ieee80211_beacon_offsets *bo)
2683 {
2684 	struct ieee80211vap *vap = ni->ni_vap;
2685 	struct ieee80211com *ic = ni->ni_ic;
2686 	struct ifnet *ifp = vap->iv_ifp;
2687 	struct ieee80211_frame *wh;
2688 	struct mbuf *m;
2689 	int pktlen;
2690 	uint8_t *frm;
2691 
2692 	/*
2693 	 * beacon frame format
2694 	 *	[8] time stamp
2695 	 *	[2] beacon interval
2696 	 *	[2] cabability information
2697 	 *	[tlv] ssid
2698 	 *	[tlv] supported rates
2699 	 *	[3] parameter set (DS)
2700 	 *	[8] CF parameter set (optional)
2701 	 *	[tlv] parameter set (IBSS/TIM)
2702 	 *	[tlv] country (optional)
2703 	 *	[3] power control (optional)
2704 	 *	[5] channel switch announcement (CSA) (optional)
2705 	 *	[tlv] extended rate phy (ERP)
2706 	 *	[tlv] extended supported rates
2707 	 *	[tlv] RSN parameters
2708 	 *	[tlv] HT capabilities
2709 	 *	[tlv] HT information
2710 	 *	[tlv] Vendor OUI HT capabilities (optional)
2711 	 *	[tlv] Vendor OUI HT information (optional)
2712 	 * XXX Vendor-specific OIDs (e.g. Atheros)
2713 	 *	[tlv] WPA parameters
2714 	 *	[tlv] WME parameters
2715 	 *	[tlv] TDMA parameters (optional)
2716 	 *	[tlv] Mesh ID (MBSS)
2717 	 *	[tlv] Mesh Conf (MBSS)
2718 	 *	[tlv] application data (optional)
2719 	 * NB: we allocate the max space required for the TIM bitmap.
2720 	 * XXX how big is this?
2721 	 */
2722 	pktlen =   8					/* time stamp */
2723 		 + sizeof(uint16_t)			/* beacon interval */
2724 		 + sizeof(uint16_t)			/* capabilities */
2725 		 + 2 + ni->ni_esslen			/* ssid */
2726 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
2727 	         + 2 + 1				/* DS parameters */
2728 		 + 2 + 6				/* CF parameters */
2729 		 + 2 + 4 + vap->iv_tim_len		/* DTIM/IBSSPARMS */
2730 		 + IEEE80211_COUNTRY_MAX_SIZE		/* country */
2731 		 + 2 + 1				/* power control */
2732 	         + sizeof(struct ieee80211_csa_ie)	/* CSA */
2733 		 + 2 + 1				/* ERP */
2734 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
2735 		 + (vap->iv_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
2736 			2*sizeof(struct ieee80211_ie_wpa) : 0)
2737 		 /* XXX conditional? */
2738 		 + 4+2*sizeof(struct ieee80211_ie_htcap)/* HT caps */
2739 		 + 4+2*sizeof(struct ieee80211_ie_htinfo)/* HT info */
2740 		 + (vap->iv_caps & IEEE80211_C_WME ?	/* WME */
2741 			sizeof(struct ieee80211_wme_param) : 0)
2742 #ifdef IEEE80211_SUPPORT_SUPERG
2743 		 + sizeof(struct ieee80211_ath_ie)	/* ATH */
2744 #endif
2745 #ifdef IEEE80211_SUPPORT_TDMA
2746 		 + (vap->iv_caps & IEEE80211_C_TDMA ?	/* TDMA */
2747 			sizeof(struct ieee80211_tdma_param) : 0)
2748 #endif
2749 #ifdef IEEE80211_SUPPORT_MESH
2750 		 + 2 + ni->ni_meshidlen
2751 		 + sizeof(struct ieee80211_meshconf_ie)
2752 #endif
2753 		 + IEEE80211_MAX_APPIE
2754 		 ;
2755 	m = ieee80211_getmgtframe(&frm,
2756 		ic->ic_headroom + sizeof(struct ieee80211_frame), pktlen);
2757 	if (m == NULL) {
2758 		IEEE80211_DPRINTF(vap, IEEE80211_MSG_ANY,
2759 			"%s: cannot get buf; size %u\n", __func__, pktlen);
2760 		vap->iv_stats.is_tx_nobuf++;
2761 		return NULL;
2762 	}
2763 	ieee80211_beacon_construct(m, frm, bo, ni);
2764 
2765 	M_PREPEND(m, sizeof(struct ieee80211_frame), MB_DONTWAIT);
2766 	KASSERT(m != NULL, ("no space for 802.11 header?"));
2767 	wh = mtod(m, struct ieee80211_frame *);
2768 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
2769 	    IEEE80211_FC0_SUBTYPE_BEACON;
2770 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
2771 	*(uint16_t *)wh->i_dur = 0;
2772 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
2773 	IEEE80211_ADDR_COPY(wh->i_addr2, vap->iv_myaddr);
2774 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
2775 	*(uint16_t *)wh->i_seq = 0;
2776 
2777 	return m;
2778 }
2779 
2780 /*
2781  * Update the dynamic parts of a beacon frame based on the current state.
2782  */
2783 int
2784 ieee80211_beacon_update(struct ieee80211_node *ni,
2785 	struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
2786 {
2787 	struct ieee80211vap *vap = ni->ni_vap;
2788 	struct ieee80211com *ic = ni->ni_ic;
2789 	int len_changed = 0;
2790 	uint16_t capinfo;
2791 
2792 	/*
2793 	 * Handle 11h channel change when we've reached the count.
2794 	 * We must recalculate the beacon frame contents to account
2795 	 * for the new channel.  Note we do this only for the first
2796 	 * vap that reaches this point; subsequent vaps just update
2797 	 * their beacon state to reflect the recalculated channel.
2798 	 */
2799 	if (isset(bo->bo_flags, IEEE80211_BEACON_CSA) &&
2800 	    vap->iv_csa_count == ic->ic_csa_count) {
2801 		vap->iv_csa_count = 0;
2802 		/*
2803 		 * Effect channel change before reconstructing the beacon
2804 		 * frame contents as many places reference ni_chan.
2805 		 */
2806 		if (ic->ic_csa_newchan != NULL)
2807 			ieee80211_csa_completeswitch(ic);
2808 		/*
2809 		 * NB: ieee80211_beacon_construct clears all pending
2810 		 * updates in bo_flags so we don't need to explicitly
2811 		 * clear IEEE80211_BEACON_CSA.
2812 		 */
2813 		ieee80211_beacon_construct(m,
2814 		    mtod(m, uint8_t*) + sizeof(struct ieee80211_frame), bo, ni);
2815 
2816 		/* XXX do WME aggressive mode processing? */
2817 		return 1;		/* just assume length changed */
2818 	}
2819 
2820 	/* XXX faster to recalculate entirely or just changes? */
2821 	capinfo = ieee80211_getcapinfo(vap, ni->ni_chan);
2822 	*bo->bo_caps = htole16(capinfo);
2823 
2824 	if (vap->iv_flags & IEEE80211_F_WME) {
2825 		struct ieee80211_wme_state *wme = &ic->ic_wme;
2826 
2827 		/*
2828 		 * Check for agressive mode change.  When there is
2829 		 * significant high priority traffic in the BSS
2830 		 * throttle back BE traffic by using conservative
2831 		 * parameters.  Otherwise BE uses agressive params
2832 		 * to optimize performance of legacy/non-QoS traffic.
2833 		 */
2834 		if (wme->wme_flags & WME_F_AGGRMODE) {
2835 			if (wme->wme_hipri_traffic >
2836 			    wme->wme_hipri_switch_thresh) {
2837 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
2838 				    "%s: traffic %u, disable aggressive mode\n",
2839 				    __func__, wme->wme_hipri_traffic);
2840 				wme->wme_flags &= ~WME_F_AGGRMODE;
2841 				ieee80211_wme_updateparams_locked(vap);
2842 				wme->wme_hipri_traffic =
2843 					wme->wme_hipri_switch_hysteresis;
2844 			} else
2845 				wme->wme_hipri_traffic = 0;
2846 		} else {
2847 			if (wme->wme_hipri_traffic <=
2848 			    wme->wme_hipri_switch_thresh) {
2849 				IEEE80211_DPRINTF(vap, IEEE80211_MSG_WME,
2850 				    "%s: traffic %u, enable aggressive mode\n",
2851 				    __func__, wme->wme_hipri_traffic);
2852 				wme->wme_flags |= WME_F_AGGRMODE;
2853 				ieee80211_wme_updateparams_locked(vap);
2854 				wme->wme_hipri_traffic = 0;
2855 			} else
2856 				wme->wme_hipri_traffic =
2857 					wme->wme_hipri_switch_hysteresis;
2858 		}
2859 		if (isset(bo->bo_flags, IEEE80211_BEACON_WME)) {
2860 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
2861 			clrbit(bo->bo_flags, IEEE80211_BEACON_WME);
2862 		}
2863 	}
2864 
2865 	if (isset(bo->bo_flags,  IEEE80211_BEACON_HTINFO)) {
2866 		ieee80211_ht_update_beacon(vap, bo);
2867 		clrbit(bo->bo_flags, IEEE80211_BEACON_HTINFO);
2868 	}
2869 #ifdef IEEE80211_SUPPORT_TDMA
2870 	if (vap->iv_caps & IEEE80211_C_TDMA) {
2871 		/*
2872 		 * NB: the beacon is potentially updated every TBTT.
2873 		 */
2874 		ieee80211_tdma_update_beacon(vap, bo);
2875 	}
2876 #endif
2877 #ifdef IEEE80211_SUPPORT_MESH
2878 	if (vap->iv_opmode == IEEE80211_M_MBSS)
2879 		ieee80211_mesh_update_beacon(vap, bo);
2880 #endif
2881 
2882 	if (vap->iv_opmode == IEEE80211_M_HOSTAP ||
2883 	    vap->iv_opmode == IEEE80211_M_MBSS) {	/* NB: no IBSS support*/
2884 		struct ieee80211_tim_ie *tie =
2885 			(struct ieee80211_tim_ie *) bo->bo_tim;
2886 		if (isset(bo->bo_flags, IEEE80211_BEACON_TIM)) {
2887 			u_int timlen, timoff, i;
2888 			/*
2889 			 * ATIM/DTIM needs updating.  If it fits in the
2890 			 * current space allocated then just copy in the
2891 			 * new bits.  Otherwise we need to move any trailing
2892 			 * data to make room.  Note that we know there is
2893 			 * contiguous space because ieee80211_beacon_allocate
2894 			 * insures there is space in the mbuf to write a
2895 			 * maximal-size virtual bitmap (based on iv_max_aid).
2896 			 */
2897 			/*
2898 			 * Calculate the bitmap size and offset, copy any
2899 			 * trailer out of the way, and then copy in the
2900 			 * new bitmap and update the information element.
2901 			 * Note that the tim bitmap must contain at least
2902 			 * one byte and any offset must be even.
2903 			 */
2904 			if (vap->iv_ps_pending != 0) {
2905 				timoff = 128;		/* impossibly large */
2906 				for (i = 0; i < vap->iv_tim_len; i++)
2907 					if (vap->iv_tim_bitmap[i]) {
2908 						timoff = i &~ 1;
2909 						break;
2910 					}
2911 				KASSERT(timoff != 128, ("tim bitmap empty!"));
2912 				for (i = vap->iv_tim_len-1; i >= timoff; i--)
2913 					if (vap->iv_tim_bitmap[i])
2914 						break;
2915 				timlen = 1 + (i - timoff);
2916 			} else {
2917 				timoff = 0;
2918 				timlen = 1;
2919 			}
2920 			if (timlen != bo->bo_tim_len) {
2921 				/* copy up/down trailer */
2922 				int adjust = tie->tim_bitmap+timlen
2923 					   - bo->bo_tim_trailer;
2924 				ovbcopy(bo->bo_tim_trailer,
2925 				    bo->bo_tim_trailer+adjust,
2926 				    bo->bo_tim_trailer_len);
2927 				bo->bo_tim_trailer += adjust;
2928 				bo->bo_erp += adjust;
2929 				bo->bo_htinfo += adjust;
2930 #ifdef IEEE80211_SUPERG_SUPPORT
2931 				bo->bo_ath += adjust;
2932 #endif
2933 #ifdef IEEE80211_TDMA_SUPPORT
2934 				bo->bo_tdma += adjust;
2935 #endif
2936 #ifdef IEEE80211_MESH_SUPPORT
2937 				bo->bo_meshconf += adjust;
2938 #endif
2939 				bo->bo_appie += adjust;
2940 				bo->bo_wme += adjust;
2941 				bo->bo_csa += adjust;
2942 				bo->bo_tim_len = timlen;
2943 
2944 				/* update information element */
2945 				tie->tim_len = 3 + timlen;
2946 				tie->tim_bitctl = timoff;
2947 				len_changed = 1;
2948 			}
2949 			memcpy(tie->tim_bitmap, vap->iv_tim_bitmap + timoff,
2950 				bo->bo_tim_len);
2951 
2952 			clrbit(bo->bo_flags, IEEE80211_BEACON_TIM);
2953 
2954 			IEEE80211_DPRINTF(vap, IEEE80211_MSG_POWER,
2955 				"%s: TIM updated, pending %u, off %u, len %u\n",
2956 				__func__, vap->iv_ps_pending, timoff, timlen);
2957 		}
2958 		/* count down DTIM period */
2959 		if (tie->tim_count == 0)
2960 			tie->tim_count = tie->tim_period - 1;
2961 		else
2962 			tie->tim_count--;
2963 		/* update state for buffered multicast frames on DTIM */
2964 		if (mcast && tie->tim_count == 0)
2965 			tie->tim_bitctl |= 1;
2966 		else
2967 			tie->tim_bitctl &= ~1;
2968 		if (isset(bo->bo_flags, IEEE80211_BEACON_CSA)) {
2969 			struct ieee80211_csa_ie *csa =
2970 			    (struct ieee80211_csa_ie *) bo->bo_csa;
2971 
2972 			/*
2973 			 * Insert or update CSA ie.  If we're just starting
2974 			 * to count down to the channel switch then we need
2975 			 * to insert the CSA ie.  Otherwise we just need to
2976 			 * drop the count.  The actual change happens above
2977 			 * when the vap's count reaches the target count.
2978 			 */
2979 			if (vap->iv_csa_count == 0) {
2980 				memmove(&csa[1], csa, bo->bo_csa_trailer_len);
2981 				bo->bo_erp += sizeof(*csa);
2982 				bo->bo_htinfo += sizeof(*csa);
2983 				bo->bo_wme += sizeof(*csa);
2984 #ifdef IEEE80211_SUPERG_SUPPORT
2985 				bo->bo_ath += sizeof(*csa);
2986 #endif
2987 #ifdef IEEE80211_TDMA_SUPPORT
2988 				bo->bo_tdma += sizeof(*csa);
2989 #endif
2990 #ifdef IEEE80211_MESH_SUPPORT
2991 				bo->bo_meshconf += sizeof(*csa);
2992 #endif
2993 				bo->bo_appie += sizeof(*csa);
2994 				bo->bo_csa_trailer_len += sizeof(*csa);
2995 				bo->bo_tim_trailer_len += sizeof(*csa);
2996 				m->m_len += sizeof(*csa);
2997 				m->m_pkthdr.len += sizeof(*csa);
2998 
2999 				ieee80211_add_csa(bo->bo_csa, vap);
3000 			} else
3001 				csa->csa_count--;
3002 			vap->iv_csa_count++;
3003 			/* NB: don't clear IEEE80211_BEACON_CSA */
3004 		}
3005 		if (isset(bo->bo_flags, IEEE80211_BEACON_ERP)) {
3006 			/*
3007 			 * ERP element needs updating.
3008 			 */
3009 			(void) ieee80211_add_erp(bo->bo_erp, ic);
3010 			clrbit(bo->bo_flags, IEEE80211_BEACON_ERP);
3011 		}
3012 #ifdef IEEE80211_SUPPORT_SUPERG
3013 		if (isset(bo->bo_flags,  IEEE80211_BEACON_ATH)) {
3014 			ieee80211_add_athcaps(bo->bo_ath, ni);
3015 			clrbit(bo->bo_flags, IEEE80211_BEACON_ATH);
3016 		}
3017 #endif
3018 	}
3019 	if (isset(bo->bo_flags, IEEE80211_BEACON_APPIE)) {
3020 		const struct ieee80211_appie *aie = vap->iv_appie_beacon;
3021 		int aielen;
3022 		uint8_t *frm;
3023 
3024 		aielen = 0;
3025 		if (aie != NULL)
3026 			aielen += aie->ie_len;
3027 		if (aielen != bo->bo_appie_len) {
3028 			/* copy up/down trailer */
3029 			int adjust = aielen - bo->bo_appie_len;
3030 			ovbcopy(bo->bo_tim_trailer, bo->bo_tim_trailer+adjust,
3031 				bo->bo_tim_trailer_len);
3032 			bo->bo_tim_trailer += adjust;
3033 			bo->bo_appie += adjust;
3034 			bo->bo_appie_len = aielen;
3035 
3036 			len_changed = 1;
3037 		}
3038 		frm = bo->bo_appie;
3039 		if (aie != NULL)
3040 			frm  = add_appie(frm, aie);
3041 		clrbit(bo->bo_flags, IEEE80211_BEACON_APPIE);
3042 	}
3043 
3044 	return len_changed;
3045 }
3046