xref: /freebsd/sys/net80211/ieee80211_output.c (revision c0b9f4fe659b6839541970eb5675e57f4d814969)
1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2005 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  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * Alternatively, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2 as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "opt_inet.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/mbuf.h>
41 #include <sys/kernel.h>
42 #include <sys/endian.h>
43 
44 #include <sys/socket.h>
45 
46 #include <net/bpf.h>
47 #include <net/ethernet.h>
48 #include <net/if.h>
49 #include <net/if_llc.h>
50 #include <net/if_media.h>
51 #include <net/if_vlan_var.h>
52 
53 #include <net80211/ieee80211_var.h>
54 
55 #ifdef INET
56 #include <netinet/in.h>
57 #include <netinet/if_ether.h>
58 #include <netinet/in_systm.h>
59 #include <netinet/ip.h>
60 #endif
61 
62 #ifdef IEEE80211_DEBUG
63 /*
64  * Decide if an outbound management frame should be
65  * printed when debugging is enabled.  This filters some
66  * of the less interesting frames that come frequently
67  * (e.g. beacons).
68  */
69 static __inline int
70 doprint(struct ieee80211com *ic, int subtype)
71 {
72 	switch (subtype) {
73 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
74 		return (ic->ic_opmode == IEEE80211_M_IBSS);
75 	}
76 	return 1;
77 }
78 #endif
79 
80 /*
81  * Set the direction field and address fields of an outgoing
82  * non-QoS frame.  Note this should be called early on in
83  * constructing a frame as it sets i_fc[1]; other bits can
84  * then be or'd in.
85  */
86 static void
87 ieee80211_send_setup(struct ieee80211com *ic,
88 	struct ieee80211_node *ni,
89 	struct ieee80211_frame *wh,
90 	int type,
91 	const u_int8_t sa[IEEE80211_ADDR_LEN],
92 	const u_int8_t da[IEEE80211_ADDR_LEN],
93 	const u_int8_t bssid[IEEE80211_ADDR_LEN])
94 {
95 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
96 
97 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
98 	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
99 		switch (ic->ic_opmode) {
100 		case IEEE80211_M_STA:
101 			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
102 			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
103 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
104 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
105 			break;
106 		case IEEE80211_M_IBSS:
107 		case IEEE80211_M_AHDEMO:
108 			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
109 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
110 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
111 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
112 			break;
113 		case IEEE80211_M_HOSTAP:
114 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
115 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
116 			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
117 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
118 			break;
119 		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
120 			break;
121 		}
122 	} else {
123 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
124 		IEEE80211_ADDR_COPY(wh->i_addr1, da);
125 		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
126 		IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
127 	}
128 	*(u_int16_t *)&wh->i_dur[0] = 0;
129 	/* NB: use non-QoS tid */
130 	*(u_int16_t *)&wh->i_seq[0] =
131 	    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
132 	ni->ni_txseqs[0]++;
133 #undef WH4
134 }
135 
136 /*
137  * Send a management frame to the specified node.  The node pointer
138  * must have a reference as the pointer will be passed to the driver
139  * and potentially held for a long time.  If the frame is successfully
140  * dispatched to the driver, then it is responsible for freeing the
141  * reference (and potentially free'ing up any associated storage).
142  */
143 static int
144 ieee80211_mgmt_output(struct ieee80211com *ic, struct ieee80211_node *ni,
145     struct mbuf *m, int type)
146 {
147 	struct ifnet *ifp = ic->ic_ifp;
148 	struct ieee80211_frame *wh;
149 
150 	KASSERT(ni != NULL, ("null node"));
151 
152 	/*
153 	 * Yech, hack alert!  We want to pass the node down to the
154 	 * driver's start routine.  If we don't do so then the start
155 	 * routine must immediately look it up again and that can
156 	 * cause a lock order reversal if, for example, this frame
157 	 * is being sent because the station is being timedout and
158 	 * the frame being sent is a DEAUTH message.  We could stick
159 	 * this in an m_tag and tack that on to the mbuf.  However
160 	 * that's rather expensive to do for every frame so instead
161 	 * we stuff it in the rcvif field since outbound frames do
162 	 * not (presently) use this.
163 	 */
164 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
165 	if (m == NULL)
166 		return ENOMEM;
167 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
168 	m->m_pkthdr.rcvif = (void *)ni;
169 
170 	wh = mtod(m, struct ieee80211_frame *);
171 	ieee80211_send_setup(ic, ni, wh,
172 		IEEE80211_FC0_TYPE_MGT | type,
173 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
174 	if ((m->m_flags & M_LINK0) != 0 && ni->ni_challenge != NULL) {
175 		m->m_flags &= ~M_LINK0;
176 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
177 			"[%s] encrypting frame (%s)\n",
178 			ether_sprintf(wh->i_addr1), __func__);
179 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
180 	}
181 #ifdef IEEE80211_DEBUG
182 	/* avoid printing too many frames */
183 	if ((ieee80211_msg_debug(ic) && doprint(ic, type)) ||
184 	    ieee80211_msg_dumppkts(ic)) {
185 		printf("[%s] send %s on channel %u\n",
186 		    ether_sprintf(wh->i_addr1),
187 		    ieee80211_mgt_subtype_name[
188 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
189 				IEEE80211_FC0_SUBTYPE_SHIFT],
190 		    ieee80211_chan2ieee(ic, ic->ic_curchan));
191 	}
192 #endif
193 	IEEE80211_NODE_STAT(ni, tx_mgmt);
194 	IF_ENQUEUE(&ic->ic_mgtq, m);
195 	ifp->if_timer = 1;
196 	if_start(ifp);
197 	return 0;
198 }
199 
200 /*
201  * Send a null data frame to the specified node.
202  *
203  * NB: the caller is assumed to have setup a node reference
204  *     for use; this is necessary to deal with a race condition
205  *     when probing for inactive stations.
206  */
207 int
208 ieee80211_send_nulldata(struct ieee80211_node *ni)
209 {
210 	struct ieee80211com *ic = ni->ni_ic;
211 	struct ifnet *ifp = ic->ic_ifp;
212 	struct mbuf *m;
213 	struct ieee80211_frame *wh;
214 
215 	MGETHDR(m, M_NOWAIT, MT_DATA);
216 	if (m == NULL) {
217 		/* XXX debug msg */
218 		ic->ic_stats.is_tx_nobuf++;
219 		ieee80211_unref_node(&ni);
220 		return ENOMEM;
221 	}
222 	m->m_pkthdr.rcvif = (void *) ni;
223 
224 	wh = mtod(m, struct ieee80211_frame *);
225 	ieee80211_send_setup(ic, ni, wh,
226 		IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
227 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
228 	/* NB: power management bit is never sent by an AP */
229 	if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
230 	    ic->ic_opmode != IEEE80211_M_HOSTAP)
231 		wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
232 	m->m_len = m->m_pkthdr.len = sizeof(struct ieee80211_frame);
233 
234 	IEEE80211_NODE_STAT(ni, tx_data);
235 
236 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
237 	    "[%s] send null data frame on channel %u, pwr mgt %s\n",
238 	    ether_sprintf(ni->ni_macaddr),
239 	    ieee80211_chan2ieee(ic, ic->ic_curchan),
240 	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");
241 
242 	IF_ENQUEUE(&ic->ic_mgtq, m);		/* cheat */
243 	if_start(ifp);
244 
245 	return 0;
246 }
247 
248 /*
249  * Assign priority to a frame based on any vlan tag assigned
250  * to the station and/or any Diffserv setting in an IP header.
251  * Finally, if an ACM policy is setup (in station mode) it's
252  * applied.
253  */
254 int
255 ieee80211_classify(struct ieee80211com *ic, struct mbuf *m, struct ieee80211_node *ni)
256 {
257 	int v_wme_ac, d_wme_ac, ac;
258 #ifdef INET
259 	struct ether_header *eh;
260 #endif
261 
262 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
263 		ac = WME_AC_BE;
264 		goto done;
265 	}
266 
267 	/*
268 	 * If node has a vlan tag then all traffic
269 	 * to it must have a matching tag.
270 	 */
271 	v_wme_ac = 0;
272 	if (ni->ni_vlan != 0) {
273 		 struct m_tag *mtag = VLAN_OUTPUT_TAG(ic->ic_ifp, m);
274 		 if (mtag == NULL) {
275 			IEEE80211_NODE_STAT(ni, tx_novlantag);
276 			return 1;
277 		}
278 		if (EVL_VLANOFTAG(VLAN_TAG_VALUE(mtag)) !=
279 		    EVL_VLANOFTAG(ni->ni_vlan)) {
280 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
281 			return 1;
282 		}
283 		/* map vlan priority to AC */
284 		switch (EVL_PRIOFTAG(ni->ni_vlan)) {
285 		case 1:
286 		case 2:
287 			v_wme_ac = WME_AC_BK;
288 			break;
289 		case 0:
290 		case 3:
291 			v_wme_ac = WME_AC_BE;
292 			break;
293 		case 4:
294 		case 5:
295 			v_wme_ac = WME_AC_VI;
296 			break;
297 		case 6:
298 		case 7:
299 			v_wme_ac = WME_AC_VO;
300 			break;
301 		}
302 	}
303 
304 #ifdef INET
305 	eh = mtod(m, struct ether_header *);
306 	if (eh->ether_type == htons(ETHERTYPE_IP)) {
307 		const struct ip *ip = (struct ip *)
308 			(mtod(m, u_int8_t *) + sizeof (*eh));
309 		/*
310 		 * IP frame, map the TOS field.
311 		 */
312 		switch (ip->ip_tos) {
313 		case 0x08:
314 		case 0x20:
315 			d_wme_ac = WME_AC_BK;	/* background */
316 			break;
317 		case 0x28:
318 		case 0xa0:
319 			d_wme_ac = WME_AC_VI;	/* video */
320 			break;
321 		case 0x30:			/* voice */
322 		case 0xe0:
323 		case 0x88:			/* XXX UPSD */
324 		case 0xb8:
325 			d_wme_ac = WME_AC_VO;
326 			break;
327 		default:
328 			d_wme_ac = WME_AC_BE;
329 			break;
330 		}
331 	} else {
332 #endif /* INET */
333 		d_wme_ac = WME_AC_BE;
334 #ifdef INET
335 	}
336 #endif
337 	/*
338 	 * Use highest priority AC.
339 	 */
340 	if (v_wme_ac > d_wme_ac)
341 		ac = v_wme_ac;
342 	else
343 		ac = d_wme_ac;
344 
345 	/*
346 	 * Apply ACM policy.
347 	 */
348 	if (ic->ic_opmode == IEEE80211_M_STA) {
349 		static const int acmap[4] = {
350 			WME_AC_BK,	/* WME_AC_BE */
351 			WME_AC_BK,	/* WME_AC_BK */
352 			WME_AC_BE,	/* WME_AC_VI */
353 			WME_AC_VI,	/* WME_AC_VO */
354 		};
355 		while (ac != WME_AC_BK &&
356 		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
357 			ac = acmap[ac];
358 	}
359 done:
360 	M_WME_SETAC(m, ac);
361 	return 0;
362 }
363 
364 /*
365  * Insure there is sufficient contiguous space to encapsulate the
366  * 802.11 data frame.  If room isn't already there, arrange for it.
367  * Drivers and cipher modules assume we have done the necessary work
368  * and fail rudely if they don't find the space they need.
369  */
370 static struct mbuf *
371 ieee80211_mbuf_adjust(struct ieee80211com *ic, int hdrsize,
372 	struct ieee80211_key *key, struct mbuf *m)
373 {
374 #define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
375 	int needed_space = hdrsize;
376 
377 	if (key != NULL) {
378 		/* XXX belongs in crypto code? */
379 		needed_space += key->wk_cipher->ic_header;
380 		/* XXX frags */
381 	}
382 	/*
383 	 * We know we are called just before stripping an Ethernet
384 	 * header and prepending an LLC header.  This means we know
385 	 * there will be
386 	 *	sizeof(struct ether_header) - sizeof(struct llc)
387 	 * bytes recovered to which we need additional space for the
388 	 * 802.11 header and any crypto header.
389 	 */
390 	/* XXX check trailing space and copy instead? */
391 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
392 		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
393 		if (n == NULL) {
394 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
395 			    "%s: cannot expand storage\n", __func__);
396 			ic->ic_stats.is_tx_nobuf++;
397 			m_freem(m);
398 			return NULL;
399 		}
400 		KASSERT(needed_space <= MHLEN,
401 		    ("not enough room, need %u got %zu\n", needed_space, MHLEN));
402 		/*
403 		 * Setup new mbuf to have leading space to prepend the
404 		 * 802.11 header and any crypto header bits that are
405 		 * required (the latter are added when the driver calls
406 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
407 		 */
408 		/* NB: must be first 'cuz it clobbers m_data */
409 		m_move_pkthdr(n, m);
410 		n->m_len = 0;			/* NB: m_gethdr does not set */
411 		n->m_data += needed_space;
412 		/*
413 		 * Pull up Ethernet header to create the expected layout.
414 		 * We could use m_pullup but that's overkill (i.e. we don't
415 		 * need the actual data) and it cannot fail so do it inline
416 		 * for speed.
417 		 */
418 		/* NB: struct ether_header is known to be contiguous */
419 		n->m_len += sizeof(struct ether_header);
420 		m->m_len -= sizeof(struct ether_header);
421 		m->m_data += sizeof(struct ether_header);
422 		/*
423 		 * Replace the head of the chain.
424 		 */
425 		n->m_next = m;
426 		m = n;
427 	}
428 	return m;
429 #undef TO_BE_RECLAIMED
430 }
431 
432 #define	KEY_UNDEFINED(k)	((k).wk_cipher == &ieee80211_cipher_none)
433 /*
434  * Return the transmit key to use in sending a unicast frame.
435  * If a unicast key is set we use that.  When no unicast key is set
436  * we fall back to the default transmit key.
437  */
438 static __inline struct ieee80211_key *
439 ieee80211_crypto_getucastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
440 {
441 	if (KEY_UNDEFINED(ni->ni_ucastkey)) {
442 		if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
443 		    KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
444 			return NULL;
445 		return &ic->ic_nw_keys[ic->ic_def_txkey];
446 	} else {
447 		return &ni->ni_ucastkey;
448 	}
449 }
450 
451 /*
452  * Return the transmit key to use in sending a multicast frame.
453  * Multicast traffic always uses the group key which is installed as
454  * the default tx key.
455  */
456 static __inline struct ieee80211_key *
457 ieee80211_crypto_getmcastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
458 {
459 	if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
460 	    KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
461 		return NULL;
462 	return &ic->ic_nw_keys[ic->ic_def_txkey];
463 }
464 
465 /*
466  * Encapsulate an outbound data frame.  The mbuf chain is updated.
467  * If an error is encountered NULL is returned.  The caller is required
468  * to provide a node reference and pullup the ethernet header in the
469  * first mbuf.
470  */
471 struct mbuf *
472 ieee80211_encap(struct ieee80211com *ic, struct mbuf *m,
473 	struct ieee80211_node *ni)
474 {
475 	struct ether_header eh;
476 	struct ieee80211_frame *wh;
477 	struct ieee80211_key *key;
478 	struct llc *llc;
479 	int hdrsize, datalen, addqos;
480 
481 	KASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
482 	memcpy(&eh, mtod(m, caddr_t), sizeof(struct ether_header));
483 
484 	/*
485 	 * Insure space for additional headers.  First identify
486 	 * transmit key to use in calculating any buffer adjustments
487 	 * required.  This is also used below to do privacy
488 	 * encapsulation work.  Then calculate the 802.11 header
489 	 * size and any padding required by the driver.
490 	 *
491 	 * Note key may be NULL if we fall back to the default
492 	 * transmit key and that is not set.  In that case the
493 	 * buffer may not be expanded as needed by the cipher
494 	 * routines, but they will/should discard it.
495 	 */
496 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
497 		if (ic->ic_opmode == IEEE80211_M_STA ||
498 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost))
499 			key = ieee80211_crypto_getucastkey(ic, ni);
500 		else
501 			key = ieee80211_crypto_getmcastkey(ic, ni);
502 		if (key == NULL && eh.ether_type != htons(ETHERTYPE_PAE)) {
503 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
504 			    "[%s] no default transmit key (%s) deftxkey %u\n",
505 			    ether_sprintf(eh.ether_dhost), __func__,
506 			    ic->ic_def_txkey);
507 			ic->ic_stats.is_tx_nodefkey++;
508 		}
509 	} else
510 		key = NULL;
511 	/* XXX 4-address format */
512 	/*
513 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
514 	 * frames so suppress use.  This may be an issue if other
515 	 * ap's require all data frames to be QoS-encapsulated
516 	 * once negotiated in which case we'll need to make this
517 	 * configurable.
518 	 */
519 	addqos = (ni->ni_flags & IEEE80211_NODE_QOS) &&
520 		 eh.ether_type != htons(ETHERTYPE_PAE);
521 	if (addqos)
522 		hdrsize = sizeof(struct ieee80211_qosframe);
523 	else
524 		hdrsize = sizeof(struct ieee80211_frame);
525 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
526 		hdrsize = roundup(hdrsize, sizeof(u_int32_t));
527 	m = ieee80211_mbuf_adjust(ic, hdrsize, key, m);
528 	if (m == NULL) {
529 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
530 		goto bad;
531 	}
532 
533 	/* NB: this could be optimized because of ieee80211_mbuf_adjust */
534 	m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
535 	llc = mtod(m, struct llc *);
536 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
537 	llc->llc_control = LLC_UI;
538 	llc->llc_snap.org_code[0] = 0;
539 	llc->llc_snap.org_code[1] = 0;
540 	llc->llc_snap.org_code[2] = 0;
541 	llc->llc_snap.ether_type = eh.ether_type;
542 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
543 
544 	M_PREPEND(m, hdrsize, M_DONTWAIT);
545 	if (m == NULL) {
546 		ic->ic_stats.is_tx_nobuf++;
547 		goto bad;
548 	}
549 	wh = mtod(m, struct ieee80211_frame *);
550 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
551 	*(u_int16_t *)wh->i_dur = 0;
552 	switch (ic->ic_opmode) {
553 	case IEEE80211_M_STA:
554 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
555 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
556 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
557 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
558 		break;
559 	case IEEE80211_M_IBSS:
560 	case IEEE80211_M_AHDEMO:
561 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
562 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
563 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
564 		/*
565 		 * NB: always use the bssid from ic_bss as the
566 		 *     neighbor's may be stale after an ibss merge
567 		 */
568 		IEEE80211_ADDR_COPY(wh->i_addr3, ic->ic_bss->ni_bssid);
569 		break;
570 	case IEEE80211_M_HOSTAP:
571 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
572 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
573 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
574 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
575 		break;
576 	case IEEE80211_M_MONITOR:
577 		goto bad;
578 	}
579 	if (m->m_flags & M_MORE_DATA)
580 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
581 	if (addqos) {
582 		struct ieee80211_qosframe *qwh =
583 			(struct ieee80211_qosframe *) wh;
584 		int ac, tid;
585 
586 		ac = M_WME_GETAC(m);
587 		/* map from access class/queue to 11e header priorty value */
588 		tid = WME_AC_TO_TID(ac);
589 		qwh->i_qos[0] = tid & IEEE80211_QOS_TID;
590 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
591 			qwh->i_qos[0] |= 1 << IEEE80211_QOS_ACKPOLICY_S;
592 		qwh->i_qos[1] = 0;
593 		qwh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
594 
595 		*(u_int16_t *)wh->i_seq =
596 		    htole16(ni->ni_txseqs[tid] << IEEE80211_SEQ_SEQ_SHIFT);
597 		ni->ni_txseqs[tid]++;
598 	} else {
599 		*(u_int16_t *)wh->i_seq =
600 		    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
601 		ni->ni_txseqs[0]++;
602 	}
603 	if (key != NULL) {
604 		/*
605 		 * IEEE 802.1X: send EAPOL frames always in the clear.
606 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
607 		 */
608 		if (eh.ether_type != htons(ETHERTYPE_PAE) ||
609 		    ((ic->ic_flags & IEEE80211_F_WPA) &&
610 		     (ic->ic_opmode == IEEE80211_M_STA ?
611 		      !KEY_UNDEFINED(*key) : !KEY_UNDEFINED(ni->ni_ucastkey)))) {
612 			wh->i_fc[1] |= IEEE80211_FC1_WEP;
613 			/* XXX do fragmentation */
614 			if (!ieee80211_crypto_enmic(ic, key, m, 0)) {
615 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
616 				    "[%s] enmic failed, discard frame\n",
617 				    ether_sprintf(eh.ether_dhost));
618 				ic->ic_stats.is_crypto_enmicfail++;
619 				goto bad;
620 			}
621 		}
622 	}
623 
624 	IEEE80211_NODE_STAT(ni, tx_data);
625 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);
626 
627 	return m;
628 bad:
629 	if (m != NULL)
630 		m_freem(m);
631 	return NULL;
632 }
633 
634 /*
635  * Add a supported rates element id to a frame.
636  */
637 static u_int8_t *
638 ieee80211_add_rates(u_int8_t *frm, const struct ieee80211_rateset *rs)
639 {
640 	int nrates;
641 
642 	*frm++ = IEEE80211_ELEMID_RATES;
643 	nrates = rs->rs_nrates;
644 	if (nrates > IEEE80211_RATE_SIZE)
645 		nrates = IEEE80211_RATE_SIZE;
646 	*frm++ = nrates;
647 	memcpy(frm, rs->rs_rates, nrates);
648 	return frm + nrates;
649 }
650 
651 /*
652  * Add an extended supported rates element id to a frame.
653  */
654 static u_int8_t *
655 ieee80211_add_xrates(u_int8_t *frm, const struct ieee80211_rateset *rs)
656 {
657 	/*
658 	 * Add an extended supported rates element if operating in 11g mode.
659 	 */
660 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
661 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
662 		*frm++ = IEEE80211_ELEMID_XRATES;
663 		*frm++ = nrates;
664 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
665 		frm += nrates;
666 	}
667 	return frm;
668 }
669 
670 /*
671  * Add an ssid elemet to a frame.
672  */
673 static u_int8_t *
674 ieee80211_add_ssid(u_int8_t *frm, const u_int8_t *ssid, u_int len)
675 {
676 	*frm++ = IEEE80211_ELEMID_SSID;
677 	*frm++ = len;
678 	memcpy(frm, ssid, len);
679 	return frm + len;
680 }
681 
682 /*
683  * Add an erp element to a frame.
684  */
685 static u_int8_t *
686 ieee80211_add_erp(u_int8_t *frm, struct ieee80211com *ic)
687 {
688 	u_int8_t erp;
689 
690 	*frm++ = IEEE80211_ELEMID_ERP;
691 	*frm++ = 1;
692 	erp = 0;
693 	if (ic->ic_nonerpsta != 0)
694 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
695 	if (ic->ic_flags & IEEE80211_F_USEPROT)
696 		erp |= IEEE80211_ERP_USE_PROTECTION;
697 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
698 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
699 	*frm++ = erp;
700 	return frm;
701 }
702 
703 static u_int8_t *
704 ieee80211_setup_wpa_ie(struct ieee80211com *ic, u_int8_t *ie)
705 {
706 #define	WPA_OUI_BYTES		0x00, 0x50, 0xf2
707 #define	ADDSHORT(frm, v) do {			\
708 	frm[0] = (v) & 0xff;			\
709 	frm[1] = (v) >> 8;			\
710 	frm += 2;				\
711 } while (0)
712 #define	ADDSELECTOR(frm, sel) do {		\
713 	memcpy(frm, sel, 4);			\
714 	frm += 4;				\
715 } while (0)
716 	static const u_int8_t oui[4] = { WPA_OUI_BYTES, WPA_OUI_TYPE };
717 	static const u_int8_t cipher_suite[][4] = {
718 		{ WPA_OUI_BYTES, WPA_CSE_WEP40 },	/* NB: 40-bit */
719 		{ WPA_OUI_BYTES, WPA_CSE_TKIP },
720 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX WRAP */
721 		{ WPA_OUI_BYTES, WPA_CSE_CCMP },
722 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
723 		{ WPA_OUI_BYTES, WPA_CSE_NULL },
724 	};
725 	static const u_int8_t wep104_suite[4] =
726 		{ WPA_OUI_BYTES, WPA_CSE_WEP104 };
727 	static const u_int8_t key_mgt_unspec[4] =
728 		{ WPA_OUI_BYTES, WPA_ASE_8021X_UNSPEC };
729 	static const u_int8_t key_mgt_psk[4] =
730 		{ WPA_OUI_BYTES, WPA_ASE_8021X_PSK };
731 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
732 	u_int8_t *frm = ie;
733 	u_int8_t *selcnt;
734 
735 	*frm++ = IEEE80211_ELEMID_VENDOR;
736 	*frm++ = 0;				/* length filled in below */
737 	memcpy(frm, oui, sizeof(oui));		/* WPA OUI */
738 	frm += sizeof(oui);
739 	ADDSHORT(frm, WPA_VERSION);
740 
741 	/* XXX filter out CKIP */
742 
743 	/* multicast cipher */
744 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
745 	    rsn->rsn_mcastkeylen >= 13)
746 		ADDSELECTOR(frm, wep104_suite);
747 	else
748 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
749 
750 	/* unicast cipher list */
751 	selcnt = frm;
752 	ADDSHORT(frm, 0);			/* selector count */
753 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
754 		selcnt[0]++;
755 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
756 	}
757 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
758 		selcnt[0]++;
759 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
760 	}
761 
762 	/* authenticator selector list */
763 	selcnt = frm;
764 	ADDSHORT(frm, 0);			/* selector count */
765 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
766 		selcnt[0]++;
767 		ADDSELECTOR(frm, key_mgt_unspec);
768 	}
769 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
770 		selcnt[0]++;
771 		ADDSELECTOR(frm, key_mgt_psk);
772 	}
773 
774 	/* optional capabilities */
775 	if (rsn->rsn_caps != 0 && rsn->rsn_caps != RSN_CAP_PREAUTH)
776 		ADDSHORT(frm, rsn->rsn_caps);
777 
778 	/* calculate element length */
779 	ie[1] = frm - ie - 2;
780 	KASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
781 		("WPA IE too big, %u > %zu",
782 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
783 	return frm;
784 #undef ADDSHORT
785 #undef ADDSELECTOR
786 #undef WPA_OUI_BYTES
787 }
788 
789 static u_int8_t *
790 ieee80211_setup_rsn_ie(struct ieee80211com *ic, u_int8_t *ie)
791 {
792 #define	RSN_OUI_BYTES		0x00, 0x0f, 0xac
793 #define	ADDSHORT(frm, v) do {			\
794 	frm[0] = (v) & 0xff;			\
795 	frm[1] = (v) >> 8;			\
796 	frm += 2;				\
797 } while (0)
798 #define	ADDSELECTOR(frm, sel) do {		\
799 	memcpy(frm, sel, 4);			\
800 	frm += 4;				\
801 } while (0)
802 	static const u_int8_t cipher_suite[][4] = {
803 		{ RSN_OUI_BYTES, RSN_CSE_WEP40 },	/* NB: 40-bit */
804 		{ RSN_OUI_BYTES, RSN_CSE_TKIP },
805 		{ RSN_OUI_BYTES, RSN_CSE_WRAP },
806 		{ RSN_OUI_BYTES, RSN_CSE_CCMP },
807 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
808 		{ RSN_OUI_BYTES, RSN_CSE_NULL },
809 	};
810 	static const u_int8_t wep104_suite[4] =
811 		{ RSN_OUI_BYTES, RSN_CSE_WEP104 };
812 	static const u_int8_t key_mgt_unspec[4] =
813 		{ RSN_OUI_BYTES, RSN_ASE_8021X_UNSPEC };
814 	static const u_int8_t key_mgt_psk[4] =
815 		{ RSN_OUI_BYTES, RSN_ASE_8021X_PSK };
816 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
817 	u_int8_t *frm = ie;
818 	u_int8_t *selcnt;
819 
820 	*frm++ = IEEE80211_ELEMID_RSN;
821 	*frm++ = 0;				/* length filled in below */
822 	ADDSHORT(frm, RSN_VERSION);
823 
824 	/* XXX filter out CKIP */
825 
826 	/* multicast cipher */
827 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
828 	    rsn->rsn_mcastkeylen >= 13)
829 		ADDSELECTOR(frm, wep104_suite);
830 	else
831 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
832 
833 	/* unicast cipher list */
834 	selcnt = frm;
835 	ADDSHORT(frm, 0);			/* selector count */
836 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
837 		selcnt[0]++;
838 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
839 	}
840 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
841 		selcnt[0]++;
842 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
843 	}
844 
845 	/* authenticator selector list */
846 	selcnt = frm;
847 	ADDSHORT(frm, 0);			/* selector count */
848 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
849 		selcnt[0]++;
850 		ADDSELECTOR(frm, key_mgt_unspec);
851 	}
852 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
853 		selcnt[0]++;
854 		ADDSELECTOR(frm, key_mgt_psk);
855 	}
856 
857 	/* optional capabilities */
858 	ADDSHORT(frm, rsn->rsn_caps);
859 	/* XXX PMKID */
860 
861 	/* calculate element length */
862 	ie[1] = frm - ie - 2;
863 	KASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
864 		("RSN IE too big, %u > %zu",
865 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
866 	return frm;
867 #undef ADDSELECTOR
868 #undef ADDSHORT
869 #undef RSN_OUI_BYTES
870 }
871 
872 /*
873  * Add a WPA/RSN element to a frame.
874  */
875 static u_int8_t *
876 ieee80211_add_wpa(u_int8_t *frm, struct ieee80211com *ic)
877 {
878 
879 	KASSERT(ic->ic_flags & IEEE80211_F_WPA, ("no WPA/RSN!"));
880 	if (ic->ic_flags & IEEE80211_F_WPA2)
881 		frm = ieee80211_setup_rsn_ie(ic, frm);
882 	if (ic->ic_flags & IEEE80211_F_WPA1)
883 		frm = ieee80211_setup_wpa_ie(ic, frm);
884 	return frm;
885 }
886 
887 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
888 /*
889  * Add a WME information element to a frame.
890  */
891 static u_int8_t *
892 ieee80211_add_wme_info(u_int8_t *frm, struct ieee80211_wme_state *wme)
893 {
894 	static const struct ieee80211_wme_info info = {
895 		.wme_id		= IEEE80211_ELEMID_VENDOR,
896 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
897 		.wme_oui	= { WME_OUI_BYTES },
898 		.wme_type	= WME_OUI_TYPE,
899 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
900 		.wme_version	= WME_VERSION,
901 		.wme_info	= 0,
902 	};
903 	memcpy(frm, &info, sizeof(info));
904 	return frm + sizeof(info);
905 }
906 
907 /*
908  * Add a WME parameters element to a frame.
909  */
910 static u_int8_t *
911 ieee80211_add_wme_param(u_int8_t *frm, struct ieee80211_wme_state *wme)
912 {
913 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
914 #define	ADDSHORT(frm, v) do {			\
915 	frm[0] = (v) & 0xff;			\
916 	frm[1] = (v) >> 8;			\
917 	frm += 2;				\
918 } while (0)
919 	/* NB: this works 'cuz a param has an info at the front */
920 	static const struct ieee80211_wme_info param = {
921 		.wme_id		= IEEE80211_ELEMID_VENDOR,
922 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
923 		.wme_oui	= { WME_OUI_BYTES },
924 		.wme_type	= WME_OUI_TYPE,
925 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
926 		.wme_version	= WME_VERSION,
927 	};
928 	int i;
929 
930 	memcpy(frm, &param, sizeof(param));
931 	frm += __offsetof(struct ieee80211_wme_info, wme_info);
932 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
933 	*frm++ = 0;					/* reserved field */
934 	for (i = 0; i < WME_NUM_AC; i++) {
935 		const struct wmeParams *ac =
936 		       &wme->wme_bssChanParams.cap_wmeParams[i];
937 		*frm++ = SM(i, WME_PARAM_ACI)
938 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
939 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
940 		       ;
941 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
942 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
943 		       ;
944 		ADDSHORT(frm, ac->wmep_txopLimit);
945 	}
946 	return frm;
947 #undef SM
948 #undef ADDSHORT
949 }
950 #undef WME_OUI_BYTES
951 
952 /*
953  * Send a probe request frame with the specified ssid
954  * and any optional information element data.
955  */
956 int
957 ieee80211_send_probereq(struct ieee80211_node *ni,
958 	const u_int8_t sa[IEEE80211_ADDR_LEN],
959 	const u_int8_t da[IEEE80211_ADDR_LEN],
960 	const u_int8_t bssid[IEEE80211_ADDR_LEN],
961 	const u_int8_t *ssid, size_t ssidlen,
962 	const void *optie, size_t optielen)
963 {
964 	struct ieee80211com *ic = ni->ni_ic;
965 	enum ieee80211_phymode mode;
966 	struct ieee80211_frame *wh;
967 	struct mbuf *m;
968 	u_int8_t *frm;
969 
970 	/*
971 	 * Hold a reference on the node so it doesn't go away until after
972 	 * the xmit is complete all the way in the driver.  On error we
973 	 * will remove our reference.
974 	 */
975 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
976 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
977 		__func__, __LINE__,
978 		ni, ether_sprintf(ni->ni_macaddr),
979 		ieee80211_node_refcnt(ni)+1);
980 	ieee80211_ref_node(ni);
981 
982 	/*
983 	 * prreq frame format
984 	 *	[tlv] ssid
985 	 *	[tlv] supported rates
986 	 *	[tlv] extended supported rates
987 	 *	[tlv] user-specified ie's
988 	 */
989 	m = ieee80211_getmgtframe(&frm,
990 		 2 + IEEE80211_NWID_LEN
991 	       + 2 + IEEE80211_RATE_SIZE
992 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
993 	       + (optie != NULL ? optielen : 0)
994 	);
995 	if (m == NULL) {
996 		ic->ic_stats.is_tx_nobuf++;
997 		ieee80211_free_node(ni);
998 		return ENOMEM;
999 	}
1000 
1001 	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
1002 	mode = ieee80211_chan2mode(ic, ic->ic_curchan);
1003 	frm = ieee80211_add_rates(frm, &ic->ic_sup_rates[mode]);
1004 	frm = ieee80211_add_xrates(frm, &ic->ic_sup_rates[mode]);
1005 
1006 	if (optie != NULL) {
1007 		memcpy(frm, optie, optielen);
1008 		frm += optielen;
1009 	}
1010 	m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1011 
1012 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1013 	if (m == NULL)
1014 		return ENOMEM;
1015 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
1016 	m->m_pkthdr.rcvif = (void *)ni;
1017 
1018 	wh = mtod(m, struct ieee80211_frame *);
1019 	ieee80211_send_setup(ic, ni, wh,
1020 		IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
1021 		sa, da, bssid);
1022 	/* XXX power management? */
1023 
1024 	IEEE80211_NODE_STAT(ni, tx_probereq);
1025 	IEEE80211_NODE_STAT(ni, tx_mgmt);
1026 
1027 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
1028 	    "[%s] send probe req on channel %u\n",
1029 	    ether_sprintf(wh->i_addr1),
1030 	    ieee80211_chan2ieee(ic, ic->ic_curchan));
1031 
1032 	IF_ENQUEUE(&ic->ic_mgtq, m);
1033 	if_start(ic->ic_ifp);
1034 	return 0;
1035 }
1036 
1037 /*
1038  * Send a management frame.  The node is for the destination (or ic_bss
1039  * when in station mode).  Nodes other than ic_bss have their reference
1040  * count bumped to reflect our use for an indeterminant time.
1041  */
1042 int
1043 ieee80211_send_mgmt(struct ieee80211com *ic, struct ieee80211_node *ni,
1044 	int type, int arg)
1045 {
1046 #define	senderr(_x, _v)	do { ic->ic_stats._v++; ret = _x; goto bad; } while (0)
1047 	struct mbuf *m;
1048 	u_int8_t *frm;
1049 	u_int16_t capinfo;
1050 	int has_challenge, is_shared_key, ret, timer, status;
1051 
1052 	KASSERT(ni != NULL, ("null node"));
1053 
1054 	/*
1055 	 * Hold a reference on the node so it doesn't go away until after
1056 	 * the xmit is complete all the way in the driver.  On error we
1057 	 * will remove our reference.
1058 	 */
1059 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1060 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1061 		__func__, __LINE__,
1062 		ni, ether_sprintf(ni->ni_macaddr),
1063 		ieee80211_node_refcnt(ni)+1);
1064 	ieee80211_ref_node(ni);
1065 
1066 	timer = 0;
1067 	switch (type) {
1068 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1069 		/*
1070 		 * probe response frame format
1071 		 *	[8] time stamp
1072 		 *	[2] beacon interval
1073 		 *	[2] cabability information
1074 		 *	[tlv] ssid
1075 		 *	[tlv] supported rates
1076 		 *	[tlv] parameter set (FH/DS)
1077 		 *	[tlv] parameter set (IBSS)
1078 		 *	[tlv] extended rate phy (ERP)
1079 		 *	[tlv] extended supported rates
1080 		 *	[tlv] WPA
1081 		 *	[tlv] WME (optional)
1082 		 */
1083 		m = ieee80211_getmgtframe(&frm,
1084 			 8
1085 		       + sizeof(u_int16_t)
1086 		       + sizeof(u_int16_t)
1087 		       + 2 + IEEE80211_NWID_LEN
1088 		       + 2 + IEEE80211_RATE_SIZE
1089 		       + 7	/* max(7,3) */
1090 		       + 6
1091 		       + 3
1092 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1093 		       /* XXX !WPA1+WPA2 fits w/o a cluster */
1094 		       + (ic->ic_flags & IEEE80211_F_WPA ?
1095 				2*sizeof(struct ieee80211_ie_wpa) : 0)
1096 		       + sizeof(struct ieee80211_wme_param)
1097 		);
1098 		if (m == NULL)
1099 			senderr(ENOMEM, is_tx_nobuf);
1100 
1101 		memset(frm, 0, 8);	/* timestamp should be filled later */
1102 		frm += 8;
1103 		*(u_int16_t *)frm = htole16(ic->ic_bss->ni_intval);
1104 		frm += 2;
1105 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1106 			capinfo = IEEE80211_CAPINFO_IBSS;
1107 		else
1108 			capinfo = IEEE80211_CAPINFO_ESS;
1109 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1110 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1111 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1112 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1113 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1114 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1115 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1116 		*(u_int16_t *)frm = htole16(capinfo);
1117 		frm += 2;
1118 
1119 		frm = ieee80211_add_ssid(frm, ic->ic_bss->ni_essid,
1120 				ic->ic_bss->ni_esslen);
1121 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1122 
1123 		if (ic->ic_phytype == IEEE80211_T_FH) {
1124                         *frm++ = IEEE80211_ELEMID_FHPARMS;
1125                         *frm++ = 5;
1126                         *frm++ = ni->ni_fhdwell & 0x00ff;
1127                         *frm++ = (ni->ni_fhdwell >> 8) & 0x00ff;
1128                         *frm++ = IEEE80211_FH_CHANSET(
1129 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1130                         *frm++ = IEEE80211_FH_CHANPAT(
1131 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1132                         *frm++ = ni->ni_fhindex;
1133 		} else {
1134 			*frm++ = IEEE80211_ELEMID_DSPARMS;
1135 			*frm++ = 1;
1136 			*frm++ = ieee80211_chan2ieee(ic, ic->ic_curchan);
1137 		}
1138 
1139 		if (ic->ic_opmode == IEEE80211_M_IBSS) {
1140 			*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1141 			*frm++ = 2;
1142 			*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1143 		}
1144 		if (ic->ic_flags & IEEE80211_F_WPA)
1145 			frm = ieee80211_add_wpa(frm, ic);
1146 		if (ic->ic_curmode == IEEE80211_MODE_11G)
1147 			frm = ieee80211_add_erp(frm, ic);
1148 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1149 		if (ic->ic_flags & IEEE80211_F_WME)
1150 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1151 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1152 		break;
1153 
1154 	case IEEE80211_FC0_SUBTYPE_AUTH:
1155 		status = arg >> 16;
1156 		arg &= 0xffff;
1157 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1158 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1159 		    ni->ni_challenge != NULL);
1160 
1161 		/*
1162 		 * Deduce whether we're doing open authentication or
1163 		 * shared key authentication.  We do the latter if
1164 		 * we're in the middle of a shared key authentication
1165 		 * handshake or if we're initiating an authentication
1166 		 * request and configured to use shared key.
1167 		 */
1168 		is_shared_key = has_challenge ||
1169 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1170 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1171 		      ic->ic_bss->ni_authmode == IEEE80211_AUTH_SHARED);
1172 
1173 		m = ieee80211_getmgtframe(&frm,
1174 			  3 * sizeof(u_int16_t)
1175 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1176 				sizeof(u_int16_t)+IEEE80211_CHALLENGE_LEN : 0)
1177 		);
1178 		if (m == NULL)
1179 			senderr(ENOMEM, is_tx_nobuf);
1180 
1181 		((u_int16_t *)frm)[0] =
1182 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1183 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1184 		((u_int16_t *)frm)[1] = htole16(arg);	/* sequence number */
1185 		((u_int16_t *)frm)[2] = htole16(status);/* status */
1186 
1187 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1188 			((u_int16_t *)frm)[3] =
1189 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1190 			    IEEE80211_ELEMID_CHALLENGE);
1191 			memcpy(&((u_int16_t *)frm)[4], ni->ni_challenge,
1192 			    IEEE80211_CHALLENGE_LEN);
1193 			m->m_pkthdr.len = m->m_len =
1194 				4 * sizeof(u_int16_t) + IEEE80211_CHALLENGE_LEN;
1195 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1196 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1197 				    "[%s] request encrypt frame (%s)\n",
1198 				    ether_sprintf(ni->ni_macaddr), __func__);
1199 				m->m_flags |= M_LINK0; /* WEP-encrypt, please */
1200 			}
1201 		} else
1202 			m->m_pkthdr.len = m->m_len = 3 * sizeof(u_int16_t);
1203 
1204 		/* XXX not right for shared key */
1205 		if (status == IEEE80211_STATUS_SUCCESS)
1206 			IEEE80211_NODE_STAT(ni, tx_auth);
1207 		else
1208 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1209 
1210 		if (ic->ic_opmode == IEEE80211_M_STA)
1211 			timer = IEEE80211_TRANS_WAIT;
1212 		break;
1213 
1214 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1215 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1216 			"[%s] send station deauthenticate (reason %d)\n",
1217 			ether_sprintf(ni->ni_macaddr), arg);
1218 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1219 		if (m == NULL)
1220 			senderr(ENOMEM, is_tx_nobuf);
1221 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1222 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1223 
1224 		IEEE80211_NODE_STAT(ni, tx_deauth);
1225 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1226 
1227 		ieee80211_node_unauthorize(ni);		/* port closed */
1228 		break;
1229 
1230 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1231 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1232 		/*
1233 		 * asreq frame format
1234 		 *	[2] capability information
1235 		 *	[2] listen interval
1236 		 *	[6*] current AP address (reassoc only)
1237 		 *	[tlv] ssid
1238 		 *	[tlv] supported rates
1239 		 *	[tlv] extended supported rates
1240 		 *	[tlv] WME
1241 		 *	[tlv] user-specified ie's
1242 		 */
1243 		m = ieee80211_getmgtframe(&frm,
1244 			 sizeof(u_int16_t)
1245 		       + sizeof(u_int16_t)
1246 		       + IEEE80211_ADDR_LEN
1247 		       + 2 + IEEE80211_NWID_LEN
1248 		       + 2 + IEEE80211_RATE_SIZE
1249 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1250 		       + sizeof(struct ieee80211_wme_info)
1251 		       + (ic->ic_opt_ie != NULL ? ic->ic_opt_ie_len : 0)
1252 		);
1253 		if (m == NULL)
1254 			senderr(ENOMEM, is_tx_nobuf);
1255 
1256 		capinfo = 0;
1257 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1258 			capinfo |= IEEE80211_CAPINFO_IBSS;
1259 		else		/* IEEE80211_M_STA */
1260 			capinfo |= IEEE80211_CAPINFO_ESS;
1261 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1262 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1263 		/*
1264 		 * NB: Some 11a AP's reject the request when
1265 		 *     short premable is set.
1266 		 */
1267 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1268 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1269 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1270 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) &&
1271 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
1272 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1273 		*(u_int16_t *)frm = htole16(capinfo);
1274 		frm += 2;
1275 
1276 		*(u_int16_t *)frm = htole16(ic->ic_lintval);
1277 		frm += 2;
1278 
1279 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
1280 			IEEE80211_ADDR_COPY(frm, ic->ic_bss->ni_bssid);
1281 			frm += IEEE80211_ADDR_LEN;
1282 		}
1283 
1284 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
1285 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1286 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1287 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1288 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
1289 		if (ic->ic_opt_ie != NULL) {
1290 			memcpy(frm, ic->ic_opt_ie, ic->ic_opt_ie_len);
1291 			frm += ic->ic_opt_ie_len;
1292 		}
1293 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1294 
1295 		timer = IEEE80211_TRANS_WAIT;
1296 		break;
1297 
1298 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1299 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1300 		/*
1301 		 * asreq frame format
1302 		 *	[2] capability information
1303 		 *	[2] status
1304 		 *	[2] association ID
1305 		 *	[tlv] supported rates
1306 		 *	[tlv] extended supported rates
1307 		 *	[tlv] WME (if enabled and STA enabled)
1308 		 */
1309 		m = ieee80211_getmgtframe(&frm,
1310 			 sizeof(u_int16_t)
1311 		       + sizeof(u_int16_t)
1312 		       + sizeof(u_int16_t)
1313 		       + 2 + IEEE80211_RATE_SIZE
1314 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1315 		       + sizeof(struct ieee80211_wme_param)
1316 		);
1317 		if (m == NULL)
1318 			senderr(ENOMEM, is_tx_nobuf);
1319 
1320 		capinfo = IEEE80211_CAPINFO_ESS;
1321 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1322 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1323 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1324 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1325 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1326 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1327 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1328 		*(u_int16_t *)frm = htole16(capinfo);
1329 		frm += 2;
1330 
1331 		*(u_int16_t *)frm = htole16(arg);	/* status */
1332 		frm += 2;
1333 
1334 		if (arg == IEEE80211_STATUS_SUCCESS) {
1335 			*(u_int16_t *)frm = htole16(ni->ni_associd);
1336 			IEEE80211_NODE_STAT(ni, tx_assoc);
1337 		} else
1338 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
1339 		frm += 2;
1340 
1341 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1342 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1343 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1344 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1345 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1346 		break;
1347 
1348 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
1349 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1350 			"[%s] send station disassociate (reason %d)\n",
1351 			ether_sprintf(ni->ni_macaddr), arg);
1352 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1353 		if (m == NULL)
1354 			senderr(ENOMEM, is_tx_nobuf);
1355 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1356 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1357 
1358 		IEEE80211_NODE_STAT(ni, tx_disassoc);
1359 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
1360 		break;
1361 
1362 	default:
1363 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1364 			"[%s] invalid mgmt frame type %u\n",
1365 			ether_sprintf(ni->ni_macaddr), type);
1366 		senderr(EINVAL, is_tx_unknownmgt);
1367 		/* NOTREACHED */
1368 	}
1369 
1370 	ret = ieee80211_mgmt_output(ic, ni, m, type);
1371 	if (ret == 0) {
1372 		if (timer)
1373 			ic->ic_mgt_timer = timer;
1374 	} else {
1375 bad:
1376 		ieee80211_free_node(ni);
1377 	}
1378 	return ret;
1379 #undef senderr
1380 }
1381 
1382 /*
1383  * Allocate a beacon frame and fillin the appropriate bits.
1384  */
1385 struct mbuf *
1386 ieee80211_beacon_alloc(struct ieee80211com *ic, struct ieee80211_node *ni,
1387 	struct ieee80211_beacon_offsets *bo)
1388 {
1389 	struct ifnet *ifp = ic->ic_ifp;
1390 	struct ieee80211_frame *wh;
1391 	struct mbuf *m;
1392 	int pktlen;
1393 	u_int8_t *frm, *efrm;
1394 	u_int16_t capinfo;
1395 	struct ieee80211_rateset *rs;
1396 
1397 	/*
1398 	 * beacon frame format
1399 	 *	[8] time stamp
1400 	 *	[2] beacon interval
1401 	 *	[2] cabability information
1402 	 *	[tlv] ssid
1403 	 *	[tlv] supported rates
1404 	 *	[3] parameter set (DS)
1405 	 *	[tlv] parameter set (IBSS/TIM)
1406 	 *	[tlv] extended rate phy (ERP)
1407 	 *	[tlv] extended supported rates
1408 	 *	[tlv] WME parameters
1409 	 *	[tlv] WPA/RSN parameters
1410 	 * XXX Vendor-specific OIDs (e.g. Atheros)
1411 	 * NB: we allocate the max space required for the TIM bitmap.
1412 	 */
1413 	rs = &ni->ni_rates;
1414 	pktlen =   8					/* time stamp */
1415 		 + sizeof(u_int16_t)			/* beacon interval */
1416 		 + sizeof(u_int16_t)			/* capabilities */
1417 		 + 2 + ni->ni_esslen			/* ssid */
1418 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
1419 	         + 2 + 1				/* DS parameters */
1420 		 + 2 + 4 + ic->ic_tim_len		/* DTIM/IBSSPARMS */
1421 		 + 2 + 1				/* ERP */
1422 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1423 		 + (ic->ic_caps & IEEE80211_C_WME ?	/* WME */
1424 			sizeof(struct ieee80211_wme_param) : 0)
1425 		 + (ic->ic_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
1426 			2*sizeof(struct ieee80211_ie_wpa) : 0)
1427 		 ;
1428 	m = ieee80211_getmgtframe(&frm, pktlen);
1429 	if (m == NULL) {
1430 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1431 			"%s: cannot get buf; size %u\n", __func__, pktlen);
1432 		ic->ic_stats.is_tx_nobuf++;
1433 		return NULL;
1434 	}
1435 
1436 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
1437 	frm += 8;
1438 	*(u_int16_t *)frm = htole16(ni->ni_intval);
1439 	frm += 2;
1440 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1441 		capinfo = IEEE80211_CAPINFO_IBSS;
1442 	else
1443 		capinfo = IEEE80211_CAPINFO_ESS;
1444 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1445 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1446 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1447 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1448 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1449 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1450 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1451 	bo->bo_caps = (u_int16_t *)frm;
1452 	*(u_int16_t *)frm = htole16(capinfo);
1453 	frm += 2;
1454 	*frm++ = IEEE80211_ELEMID_SSID;
1455 	if ((ic->ic_flags & IEEE80211_F_HIDESSID) == 0) {
1456 		*frm++ = ni->ni_esslen;
1457 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
1458 		frm += ni->ni_esslen;
1459 	} else
1460 		*frm++ = 0;
1461 	frm = ieee80211_add_rates(frm, rs);
1462 	if (ic->ic_curmode != IEEE80211_MODE_FH) {
1463 		*frm++ = IEEE80211_ELEMID_DSPARMS;
1464 		*frm++ = 1;
1465 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
1466 	}
1467 	bo->bo_tim = frm;
1468 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
1469 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1470 		*frm++ = 2;
1471 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1472 		bo->bo_tim_len = 0;
1473 	} else {
1474 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
1475 
1476 		tie->tim_ie = IEEE80211_ELEMID_TIM;
1477 		tie->tim_len = 4;	/* length */
1478 		tie->tim_count = 0;	/* DTIM count */
1479 		tie->tim_period = ic->ic_dtim_period;	/* DTIM period */
1480 		tie->tim_bitctl = 0;	/* bitmap control */
1481 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
1482 		frm += sizeof(struct ieee80211_tim_ie);
1483 		bo->bo_tim_len = 1;
1484 	}
1485 	bo->bo_trailer = frm;
1486 	if (ic->ic_flags & IEEE80211_F_WME) {
1487 		bo->bo_wme = frm;
1488 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1489 		ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1490 	}
1491 	if (ic->ic_flags & IEEE80211_F_WPA)
1492 		frm = ieee80211_add_wpa(frm, ic);
1493 	if (ic->ic_curmode == IEEE80211_MODE_11G)
1494 		frm = ieee80211_add_erp(frm, ic);
1495 	efrm = ieee80211_add_xrates(frm, rs);
1496 	bo->bo_trailer_len = efrm - bo->bo_trailer;
1497 	m->m_pkthdr.len = m->m_len = efrm - mtod(m, u_int8_t *);
1498 
1499 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1500 	KASSERT(m != NULL, ("no space for 802.11 header?"));
1501 	wh = mtod(m, struct ieee80211_frame *);
1502 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
1503 	    IEEE80211_FC0_SUBTYPE_BEACON;
1504 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1505 	*(u_int16_t *)wh->i_dur = 0;
1506 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
1507 	IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
1508 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
1509 	*(u_int16_t *)wh->i_seq = 0;
1510 
1511 	return m;
1512 }
1513 
1514 /*
1515  * Update the dynamic parts of a beacon frame based on the current state.
1516  */
1517 int
1518 ieee80211_beacon_update(struct ieee80211com *ic, struct ieee80211_node *ni,
1519 	struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
1520 {
1521 	int len_changed = 0;
1522 	u_int16_t capinfo;
1523 
1524 	IEEE80211_BEACON_LOCK(ic);
1525 	/* XXX faster to recalculate entirely or just changes? */
1526 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1527 		capinfo = IEEE80211_CAPINFO_IBSS;
1528 	else
1529 		capinfo = IEEE80211_CAPINFO_ESS;
1530 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1531 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1532 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1533 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1534 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1535 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1536 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1537 	*bo->bo_caps = htole16(capinfo);
1538 
1539 	if (ic->ic_flags & IEEE80211_F_WME) {
1540 		struct ieee80211_wme_state *wme = &ic->ic_wme;
1541 
1542 		/*
1543 		 * Check for agressive mode change.  When there is
1544 		 * significant high priority traffic in the BSS
1545 		 * throttle back BE traffic by using conservative
1546 		 * parameters.  Otherwise BE uses agressive params
1547 		 * to optimize performance of legacy/non-QoS traffic.
1548 		 */
1549 		if (wme->wme_flags & WME_F_AGGRMODE) {
1550 			if (wme->wme_hipri_traffic >
1551 			    wme->wme_hipri_switch_thresh) {
1552 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1553 				    "%s: traffic %u, disable aggressive mode\n",
1554 				    __func__, wme->wme_hipri_traffic);
1555 				wme->wme_flags &= ~WME_F_AGGRMODE;
1556 				ieee80211_wme_updateparams_locked(ic);
1557 				wme->wme_hipri_traffic =
1558 					wme->wme_hipri_switch_hysteresis;
1559 			} else
1560 				wme->wme_hipri_traffic = 0;
1561 		} else {
1562 			if (wme->wme_hipri_traffic <=
1563 			    wme->wme_hipri_switch_thresh) {
1564 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1565 				    "%s: traffic %u, enable aggressive mode\n",
1566 				    __func__, wme->wme_hipri_traffic);
1567 				wme->wme_flags |= WME_F_AGGRMODE;
1568 				ieee80211_wme_updateparams_locked(ic);
1569 				wme->wme_hipri_traffic = 0;
1570 			} else
1571 				wme->wme_hipri_traffic =
1572 					wme->wme_hipri_switch_hysteresis;
1573 		}
1574 		if (ic->ic_flags & IEEE80211_F_WMEUPDATE) {
1575 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
1576 			ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1577 		}
1578 	}
1579 
1580 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {	/* NB: no IBSS support*/
1581 		struct ieee80211_tim_ie *tie =
1582 			(struct ieee80211_tim_ie *) bo->bo_tim;
1583 		if (ic->ic_flags & IEEE80211_F_TIMUPDATE) {
1584 			u_int timlen, timoff, i;
1585 			/*
1586 			 * ATIM/DTIM needs updating.  If it fits in the
1587 			 * current space allocated then just copy in the
1588 			 * new bits.  Otherwise we need to move any trailing
1589 			 * data to make room.  Note that we know there is
1590 			 * contiguous space because ieee80211_beacon_allocate
1591 			 * insures there is space in the mbuf to write a
1592 			 * maximal-size virtual bitmap (based on ic_max_aid).
1593 			 */
1594 			/*
1595 			 * Calculate the bitmap size and offset, copy any
1596 			 * trailer out of the way, and then copy in the
1597 			 * new bitmap and update the information element.
1598 			 * Note that the tim bitmap must contain at least
1599 			 * one byte and any offset must be even.
1600 			 */
1601 			if (ic->ic_ps_pending != 0) {
1602 				timoff = 128;		/* impossibly large */
1603 				for (i = 0; i < ic->ic_tim_len; i++)
1604 					if (ic->ic_tim_bitmap[i]) {
1605 						timoff = i &~ 1;
1606 						break;
1607 					}
1608 				KASSERT(timoff != 128, ("tim bitmap empty!"));
1609 				for (i = ic->ic_tim_len-1; i >= timoff; i--)
1610 					if (ic->ic_tim_bitmap[i])
1611 						break;
1612 				timlen = 1 + (i - timoff);
1613 			} else {
1614 				timoff = 0;
1615 				timlen = 1;
1616 			}
1617 			if (timlen != bo->bo_tim_len) {
1618 				/* copy up/down trailer */
1619 				ovbcopy(bo->bo_trailer, tie->tim_bitmap+timlen,
1620 					bo->bo_trailer_len);
1621 				bo->bo_trailer = tie->tim_bitmap+timlen;
1622 				bo->bo_wme = bo->bo_trailer;
1623 				bo->bo_tim_len = timlen;
1624 
1625 				/* update information element */
1626 				tie->tim_len = 3 + timlen;
1627 				tie->tim_bitctl = timoff;
1628 				len_changed = 1;
1629 			}
1630 			memcpy(tie->tim_bitmap, ic->ic_tim_bitmap + timoff,
1631 				bo->bo_tim_len);
1632 
1633 			ic->ic_flags &= ~IEEE80211_F_TIMUPDATE;
1634 
1635 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1636 				"%s: TIM updated, pending %u, off %u, len %u\n",
1637 				__func__, ic->ic_ps_pending, timoff, timlen);
1638 		}
1639 		/* count down DTIM period */
1640 		if (tie->tim_count == 0)
1641 			tie->tim_count = tie->tim_period - 1;
1642 		else
1643 			tie->tim_count--;
1644 		/* update state for buffered multicast frames on DTIM */
1645 		if (mcast && tie->tim_count == 0)
1646 			tie->tim_bitctl |= 1;
1647 		else
1648 			tie->tim_bitctl &= ~1;
1649 	}
1650 	IEEE80211_BEACON_UNLOCK(ic);
1651 
1652 	return len_changed;
1653 }
1654 
1655 /*
1656  * Save an outbound packet for a node in power-save sleep state.
1657  * The new packet is placed on the node's saved queue, and the TIM
1658  * is changed, if necessary.
1659  */
1660 void
1661 ieee80211_pwrsave(struct ieee80211com *ic, struct ieee80211_node *ni,
1662 		  struct mbuf *m)
1663 {
1664 	int qlen, age;
1665 
1666 	IEEE80211_NODE_SAVEQ_LOCK(ni);
1667 	if (_IF_QFULL(&ni->ni_savedq)) {
1668 		_IF_DROP(&ni->ni_savedq);
1669 		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1670 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1671 			"[%s] pwr save q overflow, drops %d (size %d)\n",
1672 			ether_sprintf(ni->ni_macaddr),
1673 			ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE);
1674 #ifdef IEEE80211_DEBUG
1675 		if (ieee80211_msg_dumppkts(ic))
1676 			ieee80211_dump_pkt(mtod(m, caddr_t), m->m_len, -1, -1);
1677 #endif
1678 		m_freem(m);
1679 		return;
1680 	}
1681 	/*
1682 	 * Tag the frame with it's expiry time and insert
1683 	 * it in the queue.  The aging interval is 4 times
1684 	 * the listen interval specified by the station.
1685 	 * Frames that sit around too long are reclaimed
1686 	 * using this information.
1687 	 */
1688 	/* XXX handle overflow? */
1689 	age = ((ni->ni_intval * ic->ic_bintval) << 2) / 1024; /* TU -> secs */
1690 	_IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age);
1691 	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1692 
1693 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1694 		"[%s] save frame with age %d, %u now queued\n",
1695 		ether_sprintf(ni->ni_macaddr), age, qlen);
1696 
1697 	if (qlen == 1)
1698 		ic->ic_set_tim(ni, 1);
1699 }
1700