xref: /netbsd-src/sys/net80211/ieee80211_output.c (revision 5b84b3983f71fd20a534cfa5d1556623a8aaa717)
1 /*	$NetBSD: ieee80211_output.c,v 1.37 2005/08/21 00:07:57 dyoung Exp $	*/
2 /*-
3  * Copyright (c) 2001 Atsushi Onoe
4  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * Alternatively, this software may be distributed under the terms of the
19  * GNU General Public License ("GPL") version 2 as published by the Free
20  * Software Foundation.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifdef __FreeBSD__
36 __FBSDID("$FreeBSD: src/sys/net80211/ieee80211_output.c,v 1.26 2005/07/06 01:55:17 sam Exp $");
37 #endif
38 #ifdef __NetBSD__
39 __KERNEL_RCSID(0, "$NetBSD: ieee80211_output.c,v 1.37 2005/08/21 00:07:57 dyoung Exp $");
40 #endif
41 
42 #include "opt_inet.h"
43 
44 #ifdef __NetBSD__
45 #include "bpfilter.h"
46 #endif /* __NetBSD__ */
47 
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/mbuf.h>
51 #include <sys/kernel.h>
52 #include <sys/endian.h>
53 #include <sys/errno.h>
54 #include <sys/proc.h>
55 #include <sys/sysctl.h>
56 
57 #include <net/if.h>
58 #include <net/if_llc.h>
59 #include <net/if_media.h>
60 #include <net/if_arp.h>
61 #include <net/if_ether.h>
62 #include <net/if_llc.h>
63 #include <net/if_vlanvar.h>
64 
65 #include <net80211/ieee80211_netbsd.h>
66 #include <net80211/ieee80211_var.h>
67 
68 #if NBPFILTER > 0
69 #include <net/bpf.h>
70 #endif
71 
72 #ifdef INET
73 #include <netinet/in.h>
74 #include <netinet/in_systm.h>
75 #include <netinet/in_var.h>
76 #include <netinet/ip.h>
77 #include <net/if_ether.h>
78 #endif
79 
80 #ifdef IEEE80211_DEBUG
81 /*
82  * Decide if an outbound management frame should be
83  * printed when debugging is enabled.  This filters some
84  * of the less interesting frames that come frequently
85  * (e.g. beacons).
86  */
87 static __inline int
88 doprint(struct ieee80211com *ic, int subtype)
89 {
90 	switch (subtype) {
91 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
92 		return (ic->ic_opmode == IEEE80211_M_IBSS);
93 	}
94 	return 1;
95 }
96 #endif
97 
98 /*
99  * Send a management frame to the specified node.  The node pointer
100  * must have a reference as the pointer will be passed to the driver
101  * and potentially held for a long time.  If the frame is successfully
102  * dispatched to the driver, then it is responsible for freeing the
103  * reference (and potentially free'ing up any associated storage).
104  */
105 static int
106 ieee80211_mgmt_output(struct ieee80211com *ic, struct ieee80211_node *ni,
107     struct mbuf *m, int type)
108 {
109 	struct ifnet *ifp = ic->ic_ifp;
110 	struct ieee80211_frame *wh;
111 
112 	IASSERT(ni != NULL, ("null node"));
113 
114 	/*
115 	 * Yech, hack alert!  We want to pass the node down to the
116 	 * driver's start routine.  If we don't do so then the start
117 	 * routine must immediately look it up again and that can
118 	 * cause a lock order reversal if, for example, this frame
119 	 * is being sent because the station is being timedout and
120 	 * the frame being sent is a DEAUTH message.  We could stick
121 	 * this in an m_tag and tack that on to the mbuf.  However
122 	 * that's rather expensive to do for every frame so instead
123 	 * we stuff it in the rcvif field since outbound frames do
124 	 * not (presently) use this.
125 	 */
126 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
127 	if (m == NULL)
128 		return ENOMEM;
129 #ifdef __FreeBSD__
130 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
131 #endif
132 	m->m_pkthdr.rcvif = (void *)ni;
133 
134 	wh = mtod(m, struct ieee80211_frame *);
135 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT | type;
136 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
137 	*(u_int16_t *)wh->i_dur = 0;
138 	*(u_int16_t *)wh->i_seq =
139 	    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
140 	ni->ni_txseqs[0]++;
141 	/*
142 	 * Hack.  When sending PROBE_REQ frames while scanning we
143 	 * explicitly force a broadcast rather than (as before) clobber
144 	 * ni_macaddr and ni_bssid.  This is stopgap, we need a way
145 	 * to communicate this directly rather than do something
146 	 * implicit based on surrounding state.
147 	 */
148 	if (type == IEEE80211_FC0_SUBTYPE_PROBE_REQ &&
149 	    (ic->ic_flags & IEEE80211_F_SCAN)) {
150 		IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
151 		IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
152 		IEEE80211_ADDR_COPY(wh->i_addr3, ifp->if_broadcastaddr);
153 	} else {
154 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
155 		IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
156 		IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
157 	}
158 
159 	if ((m->m_flags & M_LINK0) != 0 && ni->ni_challenge != NULL) {
160 		m->m_flags &= ~M_LINK0;
161 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
162 			"[%s] encrypting frame (%s)\n",
163 			ether_sprintf(wh->i_addr1), __func__);
164 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
165 	}
166 #ifdef IEEE80211_DEBUG
167 	/* avoid printing too many frames */
168 	if ((ieee80211_msg_debug(ic) && doprint(ic, type)) ||
169 	    ieee80211_msg_dumppkts(ic)) {
170 		printf("[%s] send %s on channel %u\n",
171 		    ether_sprintf(wh->i_addr1),
172 		    ieee80211_mgt_subtype_name[
173 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
174 				IEEE80211_FC0_SUBTYPE_SHIFT],
175 		    ieee80211_chan2ieee(ic, ni->ni_chan));
176 	}
177 #endif
178 	IEEE80211_NODE_STAT(ni, tx_mgmt);
179 	IF_ENQUEUE(&ic->ic_mgtq, m);
180 	ifp->if_timer = 1;
181 	(*ifp->if_start)(ifp);
182 	return 0;
183 }
184 
185 /*
186  * Send a null data frame to the specified node.
187  */
188 int
189 ieee80211_send_nulldata(struct ieee80211com *ic, struct ieee80211_node *ni)
190 {
191 	struct ifnet *ifp = ic->ic_ifp;
192 	struct mbuf *m;
193 	struct ieee80211_frame *wh;
194 
195 	MGETHDR(m, M_NOWAIT, MT_HEADER);
196 	if (m == NULL) {
197 		/* XXX debug msg */
198 		ic->ic_stats.is_tx_nobuf++;
199 		return ENOMEM;
200 	}
201 	m->m_pkthdr.rcvif = (void *) ieee80211_ref_node(ni);
202 
203 	wh = mtod(m, struct ieee80211_frame *);
204 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA |
205 		IEEE80211_FC0_SUBTYPE_NODATA;
206 	*(u_int16_t *)wh->i_dur = 0;
207 	*(u_int16_t *)wh->i_seq =
208 	    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
209 	ni->ni_txseqs[0]++;
210 
211 	/* XXX WDS */
212 	wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
213 	IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_macaddr);
214 	IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
215 	IEEE80211_ADDR_COPY(wh->i_addr3, ic->ic_myaddr);
216 	m->m_len = m->m_pkthdr.len = sizeof(struct ieee80211_frame);
217 
218 	IEEE80211_NODE_STAT(ni, tx_data);
219 
220 	IF_ENQUEUE(&ic->ic_mgtq, m);		/* cheat */
221 	(*ifp->if_start)(ifp);
222 
223 	return 0;
224 }
225 
226 /*
227  * Assign priority to a frame based on any vlan tag assigned
228  * to the station and/or any Diffserv setting in an IP header.
229  * Finally, if an ACM policy is setup (in station mode) it's
230  * applied.
231  */
232 int
233 ieee80211_classify(struct ieee80211com *ic, struct mbuf *m, struct ieee80211_node *ni)
234 {
235 	int v_wme_ac, d_wme_ac, ac;
236 #ifdef INET
237 	struct ether_header *eh;
238 #endif
239 
240 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
241 		ac = WME_AC_BE;
242 		goto done;
243 	}
244 
245 	/*
246 	 * If node has a vlan tag then all traffic
247 	 * to it must have a matching tag.
248 	 */
249 	v_wme_ac = 0;
250 	if (ni->ni_vlan != 0) {
251 		/* XXX used to check ec_nvlans. */
252 		 struct m_tag *mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL);
253 		 if (mtag == NULL) {
254 			IEEE80211_NODE_STAT(ni, tx_novlantag);
255 			return 1;
256 		}
257 		if (EVL_VLANOFTAG(VLAN_TAG_VALUE(mtag)) !=
258 		    EVL_VLANOFTAG(ni->ni_vlan)) {
259 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
260 			return 1;
261 		}
262 		/* map vlan priority to AC */
263 		switch (EVL_PRIOFTAG(ni->ni_vlan)) {
264 		case 1:
265 		case 2:
266 			v_wme_ac = WME_AC_BK;
267 			break;
268 		case 0:
269 		case 3:
270 			v_wme_ac = WME_AC_BE;
271 			break;
272 		case 4:
273 		case 5:
274 			v_wme_ac = WME_AC_VI;
275 			break;
276 		case 6:
277 		case 7:
278 			v_wme_ac = WME_AC_VO;
279 			break;
280 		}
281 	}
282 
283 #ifdef INET
284 	eh = mtod(m, struct ether_header *);
285 	if (eh->ether_type == htons(ETHERTYPE_IP)) {
286 		const struct ip *ip = (struct ip *)
287 			(mtod(m, u_int8_t *) + sizeof (*eh));
288 		/*
289 		 * IP frame, map the TOS field.
290 		 */
291 		switch (ip->ip_tos) {
292 		case 0x08:
293 		case 0x20:
294 			d_wme_ac = WME_AC_BK;	/* background */
295 			break;
296 		case 0x28:
297 		case 0xa0:
298 			d_wme_ac = WME_AC_VI;	/* video */
299 			break;
300 		case 0x30:			/* voice */
301 		case 0xe0:
302 		case 0x88:			/* XXX UPSD */
303 		case 0xb8:
304 			d_wme_ac = WME_AC_VO;
305 			break;
306 		default:
307 			d_wme_ac = WME_AC_BE;
308 			break;
309 		}
310 	} else {
311 #endif /* INET */
312 		d_wme_ac = WME_AC_BE;
313 #ifdef INET
314 	}
315 #endif
316 	/*
317 	 * Use highest priority AC.
318 	 */
319 	if (v_wme_ac > d_wme_ac)
320 		ac = v_wme_ac;
321 	else
322 		ac = d_wme_ac;
323 
324 	/*
325 	 * Apply ACM policy.
326 	 */
327 	if (ic->ic_opmode == IEEE80211_M_STA) {
328 		static const int acmap[4] = {
329 			WME_AC_BK,	/* WME_AC_BE */
330 			WME_AC_BK,	/* WME_AC_BK */
331 			WME_AC_BE,	/* WME_AC_VI */
332 			WME_AC_VI,	/* WME_AC_VO */
333 		};
334 		while (ac != WME_AC_BK &&
335 		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
336 			ac = acmap[ac];
337 	}
338 done:
339 	M_WME_SETAC(m, ac);
340 	return 0;
341 }
342 
343 /*
344  * Insure there is sufficient contiguous space to encapsulate the
345  * 802.11 data frame.  If room isn't already there, arrange for it.
346  * Drivers and cipher modules assume we have done the necessary work
347  * and fail rudely if they don't find the space they need.
348  */
349 static struct mbuf *
350 ieee80211_mbuf_adjust(struct ieee80211com *ic, int hdrsize,
351 	struct ieee80211_key *key, struct mbuf *m)
352 {
353 #define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
354 	int needed_space = hdrsize;
355 	int wlen = 0;
356 
357 	if (key != NULL) {
358 		/* XXX belongs in crypto code? */
359 		needed_space += key->wk_cipher->ic_header;
360 		/* XXX frags */
361 	}
362 	/*
363 	 * We know we are called just before stripping an Ethernet
364 	 * header and prepending an LLC header.  This means we know
365 	 * there will be
366 	 *	sizeof(struct ether_header) - sizeof(struct llc)
367 	 * bytes recovered to which we need additional space for the
368 	 * 802.11 header and any crypto header.
369 	 */
370 	/* XXX check trailing space and copy instead? */
371 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
372 		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
373 		if (n == NULL) {
374 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
375 			    "%s: cannot expand storage\n", __func__);
376 			ic->ic_stats.is_tx_nobuf++;
377 			m_freem(m);
378 			return NULL;
379 		}
380 		IASSERT(needed_space <= MHLEN,
381 		    ("not enough room, need %u got %zu\n", needed_space, MHLEN));
382 		/*
383 		 * Setup new mbuf to have leading space to prepend the
384 		 * 802.11 header and any crypto header bits that are
385 		 * required (the latter are added when the driver calls
386 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
387 		 */
388 		/* NB: must be first 'cuz it clobbers m_data */
389 		M_MOVE_PKTHDR(n, m);
390 		n->m_len = 0;			/* NB: m_gethdr does not set */
391 		n->m_data += needed_space;
392 		/*
393 		 * Pull up Ethernet header to create the expected layout.
394 		 * We could use m_pullup but that's overkill (i.e. we don't
395 		 * need the actual data) and it cannot fail so do it inline
396 		 * for speed.
397 		 */
398 		/* NB: struct ether_header is known to be contiguous */
399 		n->m_len += sizeof(struct ether_header);
400 		m->m_len -= sizeof(struct ether_header);
401 		m->m_data += sizeof(struct ether_header);
402 		/*
403 		 * Replace the head of the chain.
404 		 */
405 		n->m_next = m;
406 		m = n;
407 	} else {
408                 /* We will overwrite the ethernet header in the
409                  * 802.11 encapsulation stage.  Make sure that it
410                  * is writable.
411 		 */
412 		wlen = sizeof(struct ether_header);
413 	}
414 
415 	/*
416 	 * If we're going to s/w encrypt the mbuf chain make sure it is
417 	 * writable.
418 	 */
419 	if (key != NULL && (key->wk_flags & IEEE80211_KEY_SWCRYPT) != 0)
420 		wlen = M_COPYALL;
421 
422 	if (wlen != 0 && m_makewritable(&m, 0, wlen, M_DONTWAIT) != 0) {
423 		m_freem(m);
424 		return NULL;
425 	}
426 	return m;
427 #undef TO_BE_RECLAIMED
428 }
429 
430 /*
431  * Return the transmit key to use in sending a unicast frame.
432  * If a unicast key is set we use that.  When no unicast key is set
433  * we fall back to the default transmit key.
434  */
435 static __inline struct ieee80211_key *
436 ieee80211_crypto_getucastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
437 {
438 	if (IEEE80211_KEY_UNDEFINED(ni->ni_ucastkey)) {
439 		if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
440 		    IEEE80211_KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
441 			return NULL;
442 		return &ic->ic_nw_keys[ic->ic_def_txkey];
443 	} else {
444 		return &ni->ni_ucastkey;
445 	}
446 }
447 
448 /*
449  * Return the transmit key to use in sending a multicast frame.
450  * Multicast traffic always uses the group key which is installed as
451  * the default tx key.
452  */
453 static __inline struct ieee80211_key *
454 ieee80211_crypto_getmcastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
455 {
456 	if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
457 	    IEEE80211_KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
458 		return NULL;
459 	return &ic->ic_nw_keys[ic->ic_def_txkey];
460 }
461 
462 /*
463  * Encapsulate an outbound data frame.  The mbuf chain is updated.
464  * If an error is encountered NULL is returned.  The caller is required
465  * to provide a node reference and pullup the ethernet header in the
466  * first mbuf.
467  */
468 struct mbuf *
469 ieee80211_encap(struct ieee80211com *ic, struct mbuf *m,
470 	struct ieee80211_node *ni)
471 {
472 	struct ether_header eh;
473 	struct ieee80211_frame *wh;
474 	struct ieee80211_key *key;
475 	struct llc *llc;
476 	int hdrsize, datalen, addqos;
477 
478 	IASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
479 	memcpy(&eh, mtod(m, caddr_t), sizeof(struct ether_header));
480 
481 	/*
482 	 * Insure space for additional headers.  First identify
483 	 * transmit key to use in calculating any buffer adjustments
484 	 * required.  This is also used below to do privacy
485 	 * encapsulation work.  Then calculate the 802.11 header
486 	 * size and any padding required by the driver.
487 	 *
488 	 * Note key may be NULL if we fall back to the default
489 	 * transmit key and that is not set.  In that case the
490 	 * buffer may not be expanded as needed by the cipher
491 	 * routines, but they will/should discard it.
492 	 */
493 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
494 		if (ic->ic_opmode == IEEE80211_M_STA ||
495 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost))
496 			key = ieee80211_crypto_getucastkey(ic, ni);
497 		else
498 			key = ieee80211_crypto_getmcastkey(ic, ni);
499 		if (key == NULL && eh.ether_type != htons(ETHERTYPE_PAE)) {
500 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
501 			    "[%s] no default transmit key (%s) deftxkey %u\n",
502 			    ether_sprintf(eh.ether_dhost), __func__,
503 			    ic->ic_def_txkey);
504 			ic->ic_stats.is_tx_nodefkey++;
505 		}
506 	} else
507 		key = NULL;
508 	/* XXX 4-address format */
509 	/*
510 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
511 	 * frames so suppress use.  This may be an issue if other
512 	 * ap's require all data frames to be QoS-encapsulated
513 	 * once negotiated in which case we'll need to make this
514 	 * configurable.
515 	 */
516 	addqos = (ni->ni_flags & IEEE80211_NODE_QOS) &&
517 		 eh.ether_type != htons(ETHERTYPE_PAE);
518 	if (addqos)
519 		hdrsize = sizeof(struct ieee80211_qosframe);
520 	else
521 		hdrsize = sizeof(struct ieee80211_frame);
522 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
523 		hdrsize = roundup(hdrsize, sizeof(u_int32_t));
524 	m = ieee80211_mbuf_adjust(ic, hdrsize, key, m);
525 	if (m == NULL) {
526 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
527 		goto bad;
528 	}
529 
530 	/* NB: this could be optimized because of ieee80211_mbuf_adjust */
531 	m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
532 	llc = mtod(m, struct llc *);
533 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
534 	llc->llc_control = LLC_UI;
535 	llc->llc_snap.org_code[0] = 0;
536 	llc->llc_snap.org_code[1] = 0;
537 	llc->llc_snap.org_code[2] = 0;
538 	llc->llc_snap.ether_type = eh.ether_type;
539 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
540 
541 	M_PREPEND(m, hdrsize, M_DONTWAIT);
542 	if (m == NULL) {
543 		ic->ic_stats.is_tx_nobuf++;
544 		goto bad;
545 	}
546 	wh = mtod(m, struct ieee80211_frame *);
547 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
548 	*(u_int16_t *)wh->i_dur = 0;
549 	switch (ic->ic_opmode) {
550 	case IEEE80211_M_STA:
551 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
552 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
553 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
554 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
555 		break;
556 	case IEEE80211_M_IBSS:
557 	case IEEE80211_M_AHDEMO:
558 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
559 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
560 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
561 		/*
562 		 * NB: always use the bssid from ic_bss as the
563 		 *     neighbor's may be stale after an ibss merge
564 		 */
565 		IEEE80211_ADDR_COPY(wh->i_addr3, ic->ic_bss->ni_bssid);
566 		break;
567 	case IEEE80211_M_HOSTAP:
568 #ifndef IEEE80211_NO_HOSTAP
569 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
570 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
571 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
572 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
573 #endif /* !IEEE80211_NO_HOSTAP */
574 		break;
575 	case IEEE80211_M_MONITOR:
576 		goto bad;
577 	}
578 	if (m->m_flags & M_MORE_DATA)
579 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
580 	if (addqos) {
581 		struct ieee80211_qosframe *qwh =
582 			(struct ieee80211_qosframe *) wh;
583 		int ac, tid;
584 
585 		ac = M_WME_GETAC(m);
586 		/* map from access class/queue to 11e header priorty value */
587 		tid = WME_AC_TO_TID(ac);
588 		qwh->i_qos[0] = tid & IEEE80211_QOS_TID;
589 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
590 			qwh->i_qos[0] |= 1 << IEEE80211_QOS_ACKPOLICY_S;
591 		qwh->i_qos[1] = 0;
592 		qwh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
593 
594 		*(u_int16_t *)wh->i_seq =
595 		    htole16(ni->ni_txseqs[tid] << IEEE80211_SEQ_SEQ_SHIFT);
596 		ni->ni_txseqs[tid]++;
597 	} else {
598 		*(u_int16_t *)wh->i_seq =
599 		    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
600 		ni->ni_txseqs[0]++;
601 	}
602 	if (key != NULL) {
603 		/*
604 		 * IEEE 802.1X: send EAPOL frames always in the clear.
605 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
606 		 */
607 		if (eh.ether_type != htons(ETHERTYPE_PAE) ||
608 		    ((ic->ic_flags & IEEE80211_F_WPA) &&
609 		     (ic->ic_opmode == IEEE80211_M_STA ?
610 		      !IEEE80211_KEY_UNDEFINED(*key) :
611 		      !IEEE80211_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  * Arguments in:
636  *
637  * paylen:  payload length (no FCS, no WEP header)
638  *
639  * hdrlen:  header length
640  *
641  * rate:    MSDU speed, units 500kb/s
642  *
643  * flags:   IEEE80211_F_SHPREAMBLE (use short preamble),
644  *          IEEE80211_F_SHSLOT (use short slot length)
645  *
646  * Arguments out:
647  *
648  * d:       802.11 Duration field for RTS,
649  *          802.11 Duration field for data frame,
650  *          PLCP Length for data frame,
651  *          residual octets at end of data slot
652  */
653 static int
654 ieee80211_compute_duration1(int len, int use_ack, uint32_t flags, int rate,
655     struct ieee80211_duration *d)
656 {
657 	int pre, ctsrate;
658 	int ack, bitlen, data_dur, remainder;
659 
660 	/* RTS reserves medium for SIFS | CTS | SIFS | (DATA) | SIFS | ACK
661 	 * DATA reserves medium for SIFS | ACK
662 	 *
663 	 * XXXMYC: no ACK on multicast/broadcast or control packets
664 	 */
665 
666 	bitlen = len * 8;
667 
668 	pre = IEEE80211_DUR_DS_SIFS;
669 	if ((flags & IEEE80211_F_SHPREAMBLE) != 0)
670 		pre += IEEE80211_DUR_DS_SHORT_PREAMBLE + IEEE80211_DUR_DS_FAST_PLCPHDR;
671 	else
672 		pre += IEEE80211_DUR_DS_LONG_PREAMBLE + IEEE80211_DUR_DS_SLOW_PLCPHDR;
673 
674 	d->d_residue = 0;
675 	data_dur = (bitlen * 2) / rate;
676 	remainder = (bitlen * 2) % rate;
677 	if (remainder != 0) {
678 		d->d_residue = (rate - remainder) / 16;
679 		data_dur++;
680 	}
681 
682 	switch (rate) {
683 	case 2:		/* 1 Mb/s */
684 	case 4:		/* 2 Mb/s */
685 		/* 1 - 2 Mb/s WLAN: send ACK/CTS at 1 Mb/s */
686 		ctsrate = 2;
687 		break;
688 	case 11:	/* 5.5 Mb/s */
689 	case 22:	/* 11  Mb/s */
690 	case 44:	/* 22  Mb/s */
691 		/* 5.5 - 11 Mb/s WLAN: send ACK/CTS at 2 Mb/s */
692 		ctsrate = 4;
693 		break;
694 	default:
695 		/* TBD */
696 		return -1;
697 	}
698 
699 	d->d_plcp_len = data_dur;
700 
701 	ack = (use_ack) ? pre + (IEEE80211_DUR_DS_SLOW_ACK * 2) / ctsrate : 0;
702 
703 	d->d_rts_dur =
704 	    pre + (IEEE80211_DUR_DS_SLOW_CTS * 2) / ctsrate +
705 	    pre + data_dur +
706 	    ack;
707 
708 	d->d_data_dur = ack;
709 
710 	return 0;
711 }
712 
713 /*
714  * Arguments in:
715  *
716  * wh:      802.11 header
717  *
718  * paylen:  payload length (no FCS, no WEP header)
719  *
720  * rate:    MSDU speed, units 500kb/s
721  *
722  * fraglen: fragment length, set to maximum (or higher) for no
723  *          fragmentation
724  *
725  * flags:   IEEE80211_F_PRIVACY (hardware adds WEP),
726  *          IEEE80211_F_SHPREAMBLE (use short preamble),
727  *          IEEE80211_F_SHSLOT (use short slot length)
728  *
729  * Arguments out:
730  *
731  * d0: 802.11 Duration fields (RTS/Data), PLCP Length, Service fields
732  *     of first/only fragment
733  *
734  * dn: 802.11 Duration fields (RTS/Data), PLCP Length, Service fields
735  *     of first/only fragment
736  */
737 int
738 ieee80211_compute_duration(struct ieee80211_frame_min *wh, int len,
739     uint32_t flags, int fraglen, int rate, struct ieee80211_duration *d0,
740     struct ieee80211_duration *dn, int *npktp, int debug)
741 {
742 	int ack, rc;
743 	int firstlen, hdrlen, lastlen, lastlen0, npkt, overlen, paylen;
744 
745 	if ((wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) == IEEE80211_FC1_DIR_DSTODS)
746 		hdrlen = sizeof(struct ieee80211_frame_addr4);
747 	else
748 		hdrlen = sizeof(struct ieee80211_frame);
749 
750 	paylen = len - hdrlen;
751 
752 	if ((wh->i_fc[1] & IEEE80211_FC1_WEP) != 0) {
753 		/* XXX assumes the packet is already WEP encapsulated */
754 		paylen -= IEEE80211_WEP_TOTLEN;
755 		overlen = IEEE80211_WEP_TOTLEN + IEEE80211_CRC_LEN;
756 	} else
757 		overlen = IEEE80211_CRC_LEN;
758 
759 	npkt = paylen / fraglen;
760 	lastlen0 = paylen % fraglen;
761 
762 	if (npkt == 0)			/* no fragments */
763 		lastlen = paylen + overlen;
764 	else if (lastlen0 != 0) {	/* a short "tail" fragment */
765 		lastlen = lastlen0 + overlen;
766 		npkt++;
767 	} else				/* full-length "tail" fragment */
768 		lastlen = fraglen + overlen;
769 
770 	if (npktp != NULL)
771 		*npktp = npkt;
772 
773 	if (npkt > 1)
774 		firstlen = fraglen + overlen;
775 	else
776 		firstlen = paylen + overlen;
777 
778 	if (debug) {
779 		printf("%s: npkt %d firstlen %d lastlen0 %d lastlen %d "
780 		    "fraglen %d overlen %d len %d rate %d flags %08x\n",
781 		    __func__, npkt, firstlen, lastlen0, lastlen, fraglen,
782 		    overlen, len, rate, flags);
783 	}
784 
785 	ack = !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
786 	    (wh->i_fc[1] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL;
787 
788 	rc = ieee80211_compute_duration1(firstlen + hdrlen,
789 	    ack, flags, rate, d0);
790 	if (rc == -1)
791 		return rc;
792 
793 	if (npkt <= 1) {
794 		*dn = *d0;
795 		return 0;
796 	}
797 	return ieee80211_compute_duration1(lastlen + hdrlen, ack, flags, rate,
798 	    dn);
799 }
800 
801 /*
802  * Add a supported rates element id to a frame.
803  */
804 static u_int8_t *
805 ieee80211_add_rates(u_int8_t *frm, const struct ieee80211_rateset *rs)
806 {
807 	int nrates;
808 
809 	*frm++ = IEEE80211_ELEMID_RATES;
810 	nrates = rs->rs_nrates;
811 	if (nrates > IEEE80211_RATE_SIZE)
812 		nrates = IEEE80211_RATE_SIZE;
813 	*frm++ = nrates;
814 	memcpy(frm, rs->rs_rates, nrates);
815 	return frm + nrates;
816 }
817 
818 /*
819  * Add an extended supported rates element id to a frame.
820  */
821 static u_int8_t *
822 ieee80211_add_xrates(u_int8_t *frm, const struct ieee80211_rateset *rs)
823 {
824 	/*
825 	 * Add an extended supported rates element if operating in 11g mode.
826 	 */
827 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
828 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
829 		*frm++ = IEEE80211_ELEMID_XRATES;
830 		*frm++ = nrates;
831 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
832 		frm += nrates;
833 	}
834 	return frm;
835 }
836 
837 /*
838  * Add an ssid elemet to a frame.
839  */
840 static u_int8_t *
841 ieee80211_add_ssid(u_int8_t *frm, const u_int8_t *ssid, u_int len)
842 {
843 	*frm++ = IEEE80211_ELEMID_SSID;
844 	*frm++ = len;
845 	memcpy(frm, ssid, len);
846 	return frm + len;
847 }
848 
849 /*
850  * Add an erp element to a frame.
851  */
852 static u_int8_t *
853 ieee80211_add_erp(u_int8_t *frm, struct ieee80211com *ic)
854 {
855 	u_int8_t erp;
856 
857 	*frm++ = IEEE80211_ELEMID_ERP;
858 	*frm++ = 1;
859 	erp = 0;
860 	if (ic->ic_nonerpsta != 0)
861 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
862 	if (ic->ic_flags & IEEE80211_F_USEPROT)
863 		erp |= IEEE80211_ERP_USE_PROTECTION;
864 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
865 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
866 	*frm++ = erp;
867 	return frm;
868 }
869 
870 static u_int8_t *
871 ieee80211_setup_wpa_ie(struct ieee80211com *ic, u_int8_t *ie)
872 {
873 #define	WPA_OUI_BYTES		0x00, 0x50, 0xf2
874 #define	ADDSHORT(frm, v) do {			\
875 	frm[0] = (v) & 0xff;			\
876 	frm[1] = (v) >> 8;			\
877 	frm += 2;				\
878 } while (0)
879 #define	ADDSELECTOR(frm, sel) do {		\
880 	memcpy(frm, sel, 4);			\
881 	frm += 4;				\
882 } while (0)
883 	static const u_int8_t oui[4] = { WPA_OUI_BYTES, WPA_OUI_TYPE };
884 	static const u_int8_t cipher_suite[][4] = {
885 		{ WPA_OUI_BYTES, WPA_CSE_WEP40 },	/* NB: 40-bit */
886 		{ WPA_OUI_BYTES, WPA_CSE_TKIP },
887 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX WRAP */
888 		{ WPA_OUI_BYTES, WPA_CSE_CCMP },
889 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
890 		{ WPA_OUI_BYTES, WPA_CSE_NULL },
891 	};
892 	static const u_int8_t wep104_suite[4] =
893 		{ WPA_OUI_BYTES, WPA_CSE_WEP104 };
894 	static const u_int8_t key_mgt_unspec[4] =
895 		{ WPA_OUI_BYTES, WPA_ASE_8021X_UNSPEC };
896 	static const u_int8_t key_mgt_psk[4] =
897 		{ WPA_OUI_BYTES, WPA_ASE_8021X_PSK };
898 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
899 	u_int8_t *frm = ie;
900 	u_int8_t *selcnt;
901 
902 	*frm++ = IEEE80211_ELEMID_VENDOR;
903 	*frm++ = 0;				/* length filled in below */
904 	memcpy(frm, oui, sizeof(oui));		/* WPA OUI */
905 	frm += sizeof(oui);
906 	ADDSHORT(frm, WPA_VERSION);
907 
908 	/* XXX filter out CKIP */
909 
910 	/* multicast cipher */
911 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
912 	    rsn->rsn_mcastkeylen >= 13)
913 		ADDSELECTOR(frm, wep104_suite);
914 	else
915 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
916 
917 	/* unicast cipher list */
918 	selcnt = frm;
919 	ADDSHORT(frm, 0);			/* selector count */
920 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
921 		selcnt[0]++;
922 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
923 	}
924 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
925 		selcnt[0]++;
926 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
927 	}
928 
929 	/* authenticator selector list */
930 	selcnt = frm;
931 	ADDSHORT(frm, 0);			/* selector count */
932 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
933 		selcnt[0]++;
934 		ADDSELECTOR(frm, key_mgt_unspec);
935 	}
936 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
937 		selcnt[0]++;
938 		ADDSELECTOR(frm, key_mgt_psk);
939 	}
940 
941 	/* optional capabilities */
942 	if (rsn->rsn_caps != 0 && rsn->rsn_caps != RSN_CAP_PREAUTH)
943 		ADDSHORT(frm, rsn->rsn_caps);
944 
945 	/* calculate element length */
946 	ie[1] = frm - ie - 2;
947 	IASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
948 		("WPA IE too big, %u > %zu",
949 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
950 	return frm;
951 #undef ADDSHORT
952 #undef ADDSELECTOR
953 #undef WPA_OUI_BYTES
954 }
955 
956 static u_int8_t *
957 ieee80211_setup_rsn_ie(struct ieee80211com *ic, u_int8_t *ie)
958 {
959 #define	RSN_OUI_BYTES		0x00, 0x0f, 0xac
960 #define	ADDSHORT(frm, v) do {			\
961 	frm[0] = (v) & 0xff;			\
962 	frm[1] = (v) >> 8;			\
963 	frm += 2;				\
964 } while (0)
965 #define	ADDSELECTOR(frm, sel) do {		\
966 	memcpy(frm, sel, 4);			\
967 	frm += 4;				\
968 } while (0)
969 	static const u_int8_t cipher_suite[][4] = {
970 		{ RSN_OUI_BYTES, RSN_CSE_WEP40 },	/* NB: 40-bit */
971 		{ RSN_OUI_BYTES, RSN_CSE_TKIP },
972 		{ RSN_OUI_BYTES, RSN_CSE_WRAP },
973 		{ RSN_OUI_BYTES, RSN_CSE_CCMP },
974 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
975 		{ RSN_OUI_BYTES, RSN_CSE_NULL },
976 	};
977 	static const u_int8_t wep104_suite[4] =
978 		{ RSN_OUI_BYTES, RSN_CSE_WEP104 };
979 	static const u_int8_t key_mgt_unspec[4] =
980 		{ RSN_OUI_BYTES, RSN_ASE_8021X_UNSPEC };
981 	static const u_int8_t key_mgt_psk[4] =
982 		{ RSN_OUI_BYTES, RSN_ASE_8021X_PSK };
983 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
984 	u_int8_t *frm = ie;
985 	u_int8_t *selcnt;
986 
987 	*frm++ = IEEE80211_ELEMID_RSN;
988 	*frm++ = 0;				/* length filled in below */
989 	ADDSHORT(frm, RSN_VERSION);
990 
991 	/* XXX filter out CKIP */
992 
993 	/* multicast cipher */
994 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
995 	    rsn->rsn_mcastkeylen >= 13)
996 		ADDSELECTOR(frm, wep104_suite);
997 	else
998 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
999 
1000 	/* unicast cipher list */
1001 	selcnt = frm;
1002 	ADDSHORT(frm, 0);			/* selector count */
1003 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
1004 		selcnt[0]++;
1005 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
1006 	}
1007 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
1008 		selcnt[0]++;
1009 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
1010 	}
1011 
1012 	/* authenticator selector list */
1013 	selcnt = frm;
1014 	ADDSHORT(frm, 0);			/* selector count */
1015 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
1016 		selcnt[0]++;
1017 		ADDSELECTOR(frm, key_mgt_unspec);
1018 	}
1019 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
1020 		selcnt[0]++;
1021 		ADDSELECTOR(frm, key_mgt_psk);
1022 	}
1023 
1024 	/* optional capabilities */
1025 	ADDSHORT(frm, rsn->rsn_caps);
1026 	/* XXX PMKID */
1027 
1028 	/* calculate element length */
1029 	ie[1] = frm - ie - 2;
1030 	IASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
1031 		("RSN IE too big, %u > %zu",
1032 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
1033 	return frm;
1034 #undef ADDSELECTOR
1035 #undef ADDSHORT
1036 #undef RSN_OUI_BYTES
1037 }
1038 
1039 /*
1040  * Add a WPA/RSN element to a frame.
1041  */
1042 static u_int8_t *
1043 ieee80211_add_wpa(u_int8_t *frm, struct ieee80211com *ic)
1044 {
1045 
1046 	IASSERT(ic->ic_flags & IEEE80211_F_WPA, ("no WPA/RSN!"));
1047 	if (ic->ic_flags & IEEE80211_F_WPA2)
1048 		frm = ieee80211_setup_rsn_ie(ic, frm);
1049 	if (ic->ic_flags & IEEE80211_F_WPA1)
1050 		frm = ieee80211_setup_wpa_ie(ic, frm);
1051 	return frm;
1052 }
1053 
1054 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
1055 /*
1056  * Add a WME information element to a frame.
1057  */
1058 static u_int8_t *
1059 ieee80211_add_wme_info(u_int8_t *frm, struct ieee80211_wme_state *wme)
1060 {
1061 	static const struct ieee80211_wme_info info = {
1062 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1063 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
1064 		.wme_oui	= { WME_OUI_BYTES },
1065 		.wme_type	= WME_OUI_TYPE,
1066 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
1067 		.wme_version	= WME_VERSION,
1068 		.wme_info	= 0,
1069 	};
1070 	memcpy(frm, &info, sizeof(info));
1071 	return frm + sizeof(info);
1072 }
1073 
1074 /*
1075  * Add a WME parameters element to a frame.
1076  */
1077 static u_int8_t *
1078 ieee80211_add_wme_param(u_int8_t *frm, struct ieee80211_wme_state *wme)
1079 {
1080 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
1081 #define	ADDSHORT(frm, v) do {			\
1082 	frm[0] = (v) & 0xff;			\
1083 	frm[1] = (v) >> 8;			\
1084 	frm += 2;				\
1085 } while (0)
1086 	/* NB: this works 'cuz a param has an info at the front */
1087 	static const struct ieee80211_wme_info param = {
1088 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1089 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
1090 		.wme_oui	= { WME_OUI_BYTES },
1091 		.wme_type	= WME_OUI_TYPE,
1092 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
1093 		.wme_version	= WME_VERSION,
1094 	};
1095 	int i;
1096 
1097 	memcpy(frm, &param, sizeof(param));
1098 	frm += __offsetof(struct ieee80211_wme_info, wme_info);
1099 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
1100 	*frm++ = 0;					/* reserved field */
1101 	for (i = 0; i < WME_NUM_AC; i++) {
1102 		const struct wmeParams *ac =
1103 		       &wme->wme_bssChanParams.cap_wmeParams[i];
1104 		*frm++ = SM(i, WME_PARAM_ACI)
1105 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
1106 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
1107 		       ;
1108 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
1109 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
1110 		       ;
1111 		ADDSHORT(frm, ac->wmep_txopLimit);
1112 	}
1113 	return frm;
1114 #undef SM
1115 #undef ADDSHORT
1116 }
1117 #undef WME_OUI_BYTES
1118 
1119 /*
1120  * Send a management frame.  The node is for the destination (or ic_bss
1121  * when in station mode).  Nodes other than ic_bss have their reference
1122  * count bumped to reflect our use for an indeterminant time.
1123  */
1124 int
1125 ieee80211_send_mgmt(struct ieee80211com *ic, struct ieee80211_node *ni,
1126 	int type, int arg)
1127 {
1128 #define	senderr(_x, _v)	do { ic->ic_stats._v++; ret = _x; goto bad; } while (0)
1129 	struct mbuf *m;
1130 	u_int8_t *frm;
1131 	enum ieee80211_phymode mode;
1132 	u_int16_t capinfo;
1133 	int has_challenge, is_shared_key, ret, timer, status;
1134 
1135 	IASSERT(ni != NULL, ("null node"));
1136 
1137 	/*
1138 	 * Hold a reference on the node so it doesn't go away until after
1139 	 * the xmit is complete all the way in the driver.  On error we
1140 	 * will remove our reference.
1141 	 */
1142 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1143 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1144 		__func__, __LINE__,
1145 		ni, ether_sprintf(ni->ni_macaddr),
1146 		ieee80211_node_refcnt(ni)+1);
1147 	ieee80211_ref_node(ni);
1148 
1149 	timer = 0;
1150 	switch (type) {
1151 	case IEEE80211_FC0_SUBTYPE_PROBE_REQ:
1152 		/*
1153 		 * prreq frame format
1154 		 *	[tlv] ssid
1155 		 *	[tlv] supported rates
1156 		 *	[tlv] extended supported rates
1157 		 *	[tlv] user-specified ie's
1158 		 */
1159 		m = ieee80211_getmgtframe(&frm,
1160 			 2 + IEEE80211_NWID_LEN
1161 		       + 2 + IEEE80211_RATE_SIZE
1162 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1163 		       + (ic->ic_opt_ie != NULL ? ic->ic_opt_ie_len : 0)
1164 		);
1165 		if (m == NULL)
1166 			senderr(ENOMEM, is_tx_nobuf);
1167 
1168 		frm = ieee80211_add_ssid(frm, ic->ic_des_essid, ic->ic_des_esslen);
1169 		mode = ieee80211_chan2mode(ic, ni->ni_chan);
1170 		frm = ieee80211_add_rates(frm, &ic->ic_sup_rates[mode]);
1171 		frm = ieee80211_add_xrates(frm, &ic->ic_sup_rates[mode]);
1172 		if (ic->ic_opt_ie != NULL) {
1173 			memcpy(frm, ic->ic_opt_ie, ic->ic_opt_ie_len);
1174 			frm += ic->ic_opt_ie_len;
1175 		}
1176 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1177 
1178 		IEEE80211_NODE_STAT(ni, tx_probereq);
1179 		if (ic->ic_opmode == IEEE80211_M_STA)
1180 			timer = IEEE80211_TRANS_WAIT;
1181 		break;
1182 
1183 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1184 		/*
1185 		 * probe response frame format
1186 		 *	[8] time stamp
1187 		 *	[2] beacon interval
1188 		 *	[2] cabability information
1189 		 *	[tlv] ssid
1190 		 *	[tlv] supported rates
1191 		 *	[tlv] parameter set (FH/DS)
1192 		 *	[tlv] parameter set (IBSS)
1193 		 *	[tlv] extended rate phy (ERP)
1194 		 *	[tlv] extended supported rates
1195 		 *	[tlv] WPA
1196 		 *	[tlv] WME (optional)
1197 		 */
1198 		m = ieee80211_getmgtframe(&frm,
1199 			 8
1200 		       + sizeof(u_int16_t)
1201 		       + sizeof(u_int16_t)
1202 		       + 2 + IEEE80211_NWID_LEN
1203 		       + 2 + IEEE80211_RATE_SIZE
1204 		       + 7	/* max(7,3) */
1205 		       + 6
1206 		       + 3
1207 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1208 		       /* XXX !WPA1+WPA2 fits w/o a cluster */
1209 		       + (ic->ic_flags & IEEE80211_F_WPA ?
1210 				2*sizeof(struct ieee80211_ie_wpa) : 0)
1211 		       + sizeof(struct ieee80211_wme_param)
1212 		);
1213 		if (m == NULL)
1214 			senderr(ENOMEM, is_tx_nobuf);
1215 
1216 		memset(frm, 0, 8);	/* timestamp should be filled later */
1217 		frm += 8;
1218 		*(u_int16_t *)frm = htole16(ic->ic_bss->ni_intval);
1219 		frm += 2;
1220 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1221 			capinfo = IEEE80211_CAPINFO_IBSS;
1222 		else
1223 			capinfo = IEEE80211_CAPINFO_ESS;
1224 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1225 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1226 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1227 		    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1228 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1229 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1230 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1231 		*(u_int16_t *)frm = htole16(capinfo);
1232 		frm += 2;
1233 
1234 		frm = ieee80211_add_ssid(frm, ic->ic_bss->ni_essid,
1235 				ic->ic_bss->ni_esslen);
1236 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1237 
1238 		if (ic->ic_phytype == IEEE80211_T_FH) {
1239                         *frm++ = IEEE80211_ELEMID_FHPARMS;
1240                         *frm++ = 5;
1241                         *frm++ = ni->ni_fhdwell & 0x00ff;
1242                         *frm++ = (ni->ni_fhdwell >> 8) & 0x00ff;
1243                         *frm++ = IEEE80211_FH_CHANSET(
1244 			    ieee80211_chan2ieee(ic, ni->ni_chan));
1245                         *frm++ = IEEE80211_FH_CHANPAT(
1246 			    ieee80211_chan2ieee(ic, ni->ni_chan));
1247                         *frm++ = ni->ni_fhindex;
1248 		} else {
1249 			*frm++ = IEEE80211_ELEMID_DSPARMS;
1250 			*frm++ = 1;
1251 			*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
1252 		}
1253 
1254 		if (ic->ic_opmode == IEEE80211_M_IBSS) {
1255 			*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1256 			*frm++ = 2;
1257 			*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1258 		}
1259 		if (ic->ic_flags & IEEE80211_F_WPA)
1260 			frm = ieee80211_add_wpa(frm, ic);
1261 		if (ic->ic_curmode == IEEE80211_MODE_11G)
1262 			frm = ieee80211_add_erp(frm, ic);
1263 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1264 		if (ic->ic_flags & IEEE80211_F_WME)
1265 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1266 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1267 		break;
1268 
1269 	case IEEE80211_FC0_SUBTYPE_AUTH:
1270 		status = arg >> 16;
1271 		arg &= 0xffff;
1272 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1273 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1274 		    ni->ni_challenge != NULL);
1275 
1276 		/*
1277 		 * Deduce whether we're doing open authentication or
1278 		 * shared key authentication.  We do the latter if
1279 		 * we're in the middle of a shared key authentication
1280 		 * handshake or if we're initiating an authentication
1281 		 * request and configured to use shared key.
1282 		 */
1283 		is_shared_key = has_challenge ||
1284 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1285 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1286 		      ic->ic_bss->ni_authmode == IEEE80211_AUTH_SHARED);
1287 
1288 		m = ieee80211_getmgtframe(&frm,
1289 			  3 * sizeof(u_int16_t)
1290 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1291 				sizeof(u_int16_t)+IEEE80211_CHALLENGE_LEN : 0)
1292 		);
1293 		if (m == NULL)
1294 			senderr(ENOMEM, is_tx_nobuf);
1295 
1296 		((u_int16_t *)frm)[0] =
1297 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1298 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1299 		((u_int16_t *)frm)[1] = htole16(arg);	/* sequence number */
1300 		((u_int16_t *)frm)[2] = htole16(status);/* status */
1301 
1302 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1303 			((u_int16_t *)frm)[3] =
1304 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1305 			    IEEE80211_ELEMID_CHALLENGE);
1306 			memcpy(&((u_int16_t *)frm)[4], ni->ni_challenge,
1307 			    IEEE80211_CHALLENGE_LEN);
1308 			m->m_pkthdr.len = m->m_len =
1309 				4 * sizeof(u_int16_t) + IEEE80211_CHALLENGE_LEN;
1310 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1311 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1312 				    "[%s] request encrypt frame (%s)\n",
1313 				    ether_sprintf(ni->ni_macaddr), __func__);
1314 				m->m_flags |= M_LINK0; /* WEP-encrypt, please */
1315 			}
1316 		} else
1317 			m->m_pkthdr.len = m->m_len = 3 * sizeof(u_int16_t);
1318 
1319 		/* XXX not right for shared key */
1320 		if (status == IEEE80211_STATUS_SUCCESS)
1321 			IEEE80211_NODE_STAT(ni, tx_auth);
1322 		else
1323 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1324 
1325 		if (ic->ic_opmode == IEEE80211_M_STA)
1326 			timer = IEEE80211_TRANS_WAIT;
1327 		break;
1328 
1329 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1330 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1331 			"[%s] send station deauthenticate (reason %d)\n",
1332 			ether_sprintf(ni->ni_macaddr), arg);
1333 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1334 		if (m == NULL)
1335 			senderr(ENOMEM, is_tx_nobuf);
1336 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1337 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1338 
1339 		IEEE80211_NODE_STAT(ni, tx_deauth);
1340 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1341 
1342 		ieee80211_node_unauthorize(ic, ni);	/* port closed */
1343 		break;
1344 
1345 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1346 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1347 		/*
1348 		 * asreq frame format
1349 		 *	[2] capability information
1350 		 *	[2] listen interval
1351 		 *	[6*] current AP address (reassoc only)
1352 		 *	[tlv] ssid
1353 		 *	[tlv] supported rates
1354 		 *	[tlv] extended supported rates
1355 		 *	[tlv] WME
1356 		 *	[tlv] user-specified ie's
1357 		 */
1358 		m = ieee80211_getmgtframe(&frm,
1359 			 sizeof(u_int16_t)
1360 		       + sizeof(u_int16_t)
1361 		       + IEEE80211_ADDR_LEN
1362 		       + 2 + IEEE80211_NWID_LEN
1363 		       + 2 + IEEE80211_RATE_SIZE
1364 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1365 		       + sizeof(struct ieee80211_wme_info)
1366 		       + (ic->ic_opt_ie != NULL ? ic->ic_opt_ie_len : 0)
1367 		);
1368 		if (m == NULL)
1369 			senderr(ENOMEM, is_tx_nobuf);
1370 
1371 		capinfo = 0;
1372 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1373 			capinfo |= IEEE80211_CAPINFO_IBSS;
1374 		else		/* IEEE80211_M_STA */
1375 			capinfo |= IEEE80211_CAPINFO_ESS;
1376 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1377 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1378 		/*
1379 		 * NB: Some 11a AP's reject the request when
1380 		 *     short premable is set.
1381 		 */
1382 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1383 		    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1384 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1385 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) &&
1386 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
1387 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1388 		*(u_int16_t *)frm = htole16(capinfo);
1389 		frm += 2;
1390 
1391 		*(u_int16_t *)frm = htole16(ic->ic_lintval);
1392 		frm += 2;
1393 
1394 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
1395 			IEEE80211_ADDR_COPY(frm, ic->ic_bss->ni_bssid);
1396 			frm += IEEE80211_ADDR_LEN;
1397 		}
1398 
1399 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
1400 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1401 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1402 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1403 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
1404 		if (ic->ic_opt_ie != NULL) {
1405 			memcpy(frm, ic->ic_opt_ie, ic->ic_opt_ie_len);
1406 			frm += ic->ic_opt_ie_len;
1407 		}
1408 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1409 
1410 		timer = IEEE80211_TRANS_WAIT;
1411 		break;
1412 
1413 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1414 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1415 		/*
1416 		 * asreq frame format
1417 		 *	[2] capability information
1418 		 *	[2] status
1419 		 *	[2] association ID
1420 		 *	[tlv] supported rates
1421 		 *	[tlv] extended supported rates
1422 		 *	[tlv] WME (if enabled and STA enabled)
1423 		 */
1424 		m = ieee80211_getmgtframe(&frm,
1425 			 sizeof(u_int16_t)
1426 		       + sizeof(u_int16_t)
1427 		       + sizeof(u_int16_t)
1428 		       + 2 + IEEE80211_RATE_SIZE
1429 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1430 		       + sizeof(struct ieee80211_wme_param)
1431 		);
1432 		if (m == NULL)
1433 			senderr(ENOMEM, is_tx_nobuf);
1434 
1435 		capinfo = IEEE80211_CAPINFO_ESS;
1436 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1437 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1438 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1439 		    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1440 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1441 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1442 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1443 		*(u_int16_t *)frm = htole16(capinfo);
1444 		frm += 2;
1445 
1446 		*(u_int16_t *)frm = htole16(arg);	/* status */
1447 		frm += 2;
1448 
1449 		if (arg == IEEE80211_STATUS_SUCCESS) {
1450 			*(u_int16_t *)frm = htole16(ni->ni_associd);
1451 			IEEE80211_NODE_STAT(ni, tx_assoc);
1452 		} else
1453 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
1454 		frm += 2;
1455 
1456 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1457 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1458 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1459 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1460 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1461 		break;
1462 
1463 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
1464 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1465 			"[%s] send station disassociate (reason %d)\n",
1466 			ether_sprintf(ni->ni_macaddr), arg);
1467 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1468 		if (m == NULL)
1469 			senderr(ENOMEM, is_tx_nobuf);
1470 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1471 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1472 
1473 		IEEE80211_NODE_STAT(ni, tx_disassoc);
1474 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
1475 		break;
1476 
1477 	default:
1478 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1479 			"[%s] invalid mgmt frame type %u\n",
1480 			ether_sprintf(ni->ni_macaddr), type);
1481 		senderr(EINVAL, is_tx_unknownmgt);
1482 		/* NOTREACHED */
1483 	}
1484 
1485 	ret = ieee80211_mgmt_output(ic, ni, m, type);
1486 	if (ret == 0) {
1487 		if (timer)
1488 			ic->ic_mgt_timer = timer;
1489 	} else {
1490 bad:
1491 		ieee80211_free_node(ni);
1492 	}
1493 	return ret;
1494 #undef senderr
1495 }
1496 
1497 /*
1498  * Allocate a beacon frame and fillin the appropriate bits.
1499  */
1500 struct mbuf *
1501 ieee80211_beacon_alloc(struct ieee80211com *ic, struct ieee80211_node *ni,
1502 	struct ieee80211_beacon_offsets *bo)
1503 {
1504 	struct ifnet *ifp = ic->ic_ifp;
1505 	struct ieee80211_frame *wh;
1506 	struct mbuf *m;
1507 	int pktlen;
1508 	u_int8_t *frm, *efrm;
1509 	u_int16_t capinfo;
1510 	struct ieee80211_rateset *rs;
1511 
1512 	/*
1513 	 * beacon frame format
1514 	 *	[8] time stamp
1515 	 *	[2] beacon interval
1516 	 *	[2] cabability information
1517 	 *	[tlv] ssid
1518 	 *	[tlv] supported rates
1519 	 *	[3] parameter set (DS)
1520 	 *	[tlv] parameter set (IBSS/TIM)
1521 	 *	[tlv] extended rate phy (ERP)
1522 	 *	[tlv] extended supported rates
1523 	 *	[tlv] WME parameters
1524 	 *	[tlv] WPA/RSN parameters
1525 	 * XXX Vendor-specific OIDs (e.g. Atheros)
1526 	 * NB: we allocate the max space required for the TIM bitmap.
1527 	 */
1528 	rs = &ni->ni_rates;
1529 	pktlen =   8					/* time stamp */
1530 		 + sizeof(u_int16_t)			/* beacon interval */
1531 		 + sizeof(u_int16_t)			/* capabilities */
1532 		 + 2 + ni->ni_esslen			/* ssid */
1533 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
1534 	         + 2 + 1				/* DS parameters */
1535 		 + 2 + 4 + ic->ic_tim_len		/* DTIM/IBSSPARMS */
1536 		 + 2 + 1				/* ERP */
1537 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1538 		 + (ic->ic_caps & IEEE80211_C_WME ?	/* WME */
1539 			sizeof(struct ieee80211_wme_param) : 0)
1540 		 + (ic->ic_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
1541 			2*sizeof(struct ieee80211_ie_wpa) : 0)
1542 		 ;
1543 	m = ieee80211_getmgtframe(&frm, pktlen);
1544 	if (m == NULL) {
1545 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1546 			"%s: cannot get buf; size %u\n", __func__, pktlen);
1547 		ic->ic_stats.is_tx_nobuf++;
1548 		return NULL;
1549 	}
1550 
1551 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
1552 	frm += 8;
1553 	*(u_int16_t *)frm = htole16(ni->ni_intval);
1554 	frm += 2;
1555 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1556 		capinfo = IEEE80211_CAPINFO_IBSS;
1557 	else
1558 		capinfo = IEEE80211_CAPINFO_ESS;
1559 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1560 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1561 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1562 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1563 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1564 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1565 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1566 	bo->bo_caps = (u_int16_t *)frm;
1567 	*(u_int16_t *)frm = htole16(capinfo);
1568 	frm += 2;
1569 	*frm++ = IEEE80211_ELEMID_SSID;
1570 	if ((ic->ic_flags & IEEE80211_F_HIDESSID) == 0) {
1571 		*frm++ = ni->ni_esslen;
1572 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
1573 		frm += ni->ni_esslen;
1574 	} else
1575 		*frm++ = 0;
1576 	frm = ieee80211_add_rates(frm, rs);
1577 	if (ic->ic_curmode != IEEE80211_MODE_FH) {
1578 		*frm++ = IEEE80211_ELEMID_DSPARMS;
1579 		*frm++ = 1;
1580 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
1581 	}
1582 	bo->bo_tim = frm;
1583 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
1584 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1585 		*frm++ = 2;
1586 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1587 		bo->bo_tim_len = 0;
1588 	} else {
1589 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
1590 
1591 		tie->tim_ie = IEEE80211_ELEMID_TIM;
1592 		tie->tim_len = 4;	/* length */
1593 		tie->tim_count = 0;	/* DTIM count */
1594 		tie->tim_period = ic->ic_dtim_period;	/* DTIM period */
1595 		tie->tim_bitctl = 0;	/* bitmap control */
1596 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
1597 		frm += sizeof(struct ieee80211_tim_ie);
1598 		bo->bo_tim_len = 1;
1599 	}
1600 	bo->bo_trailer = frm;
1601 	if (ic->ic_flags & IEEE80211_F_WME) {
1602 		bo->bo_wme = frm;
1603 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1604 		ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1605 	}
1606 	if (ic->ic_flags & IEEE80211_F_WPA)
1607 		frm = ieee80211_add_wpa(frm, ic);
1608 	if (ic->ic_curmode == IEEE80211_MODE_11G)
1609 		frm = ieee80211_add_erp(frm, ic);
1610 	efrm = ieee80211_add_xrates(frm, rs);
1611 	bo->bo_trailer_len = efrm - bo->bo_trailer;
1612 	m->m_pkthdr.len = m->m_len = efrm - mtod(m, u_int8_t *);
1613 
1614 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1615 	IASSERT(m != NULL, ("no space for 802.11 header?"));
1616 	wh = mtod(m, struct ieee80211_frame *);
1617 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
1618 	    IEEE80211_FC0_SUBTYPE_BEACON;
1619 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1620 	*(u_int16_t *)wh->i_dur = 0;
1621 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
1622 	IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
1623 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
1624 	*(u_int16_t *)wh->i_seq = 0;
1625 
1626 	return m;
1627 }
1628 
1629 /*
1630  * Update the dynamic parts of a beacon frame based on the current state.
1631  */
1632 int
1633 ieee80211_beacon_update(struct ieee80211com *ic, struct ieee80211_node *ni,
1634 	struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
1635 {
1636 	int len_changed = 0;
1637 	u_int16_t capinfo;
1638 
1639 	IEEE80211_BEACON_LOCK(ic);
1640 	/* XXX faster to recalculate entirely or just changes? */
1641 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1642 		capinfo = IEEE80211_CAPINFO_IBSS;
1643 	else
1644 		capinfo = IEEE80211_CAPINFO_ESS;
1645 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1646 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1647 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1648 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1649 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1650 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1651 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1652 	*bo->bo_caps = htole16(capinfo);
1653 
1654 	if (ic->ic_flags & IEEE80211_F_WME) {
1655 		struct ieee80211_wme_state *wme = &ic->ic_wme;
1656 
1657 		/*
1658 		 * Check for agressive mode change.  When there is
1659 		 * significant high priority traffic in the BSS
1660 		 * throttle back BE traffic by using conservative
1661 		 * parameters.  Otherwise BE uses agressive params
1662 		 * to optimize performance of legacy/non-QoS traffic.
1663 		 */
1664 		if (wme->wme_flags & WME_F_AGGRMODE) {
1665 			if (wme->wme_hipri_traffic >
1666 			    wme->wme_hipri_switch_thresh) {
1667 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1668 				    "%s: traffic %u, disable aggressive mode\n",
1669 				    __func__, wme->wme_hipri_traffic);
1670 				wme->wme_flags &= ~WME_F_AGGRMODE;
1671 				ieee80211_wme_updateparams_locked(ic);
1672 				wme->wme_hipri_traffic =
1673 					wme->wme_hipri_switch_hysteresis;
1674 			} else
1675 				wme->wme_hipri_traffic = 0;
1676 		} else {
1677 			if (wme->wme_hipri_traffic <=
1678 			    wme->wme_hipri_switch_thresh) {
1679 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1680 				    "%s: traffic %u, enable aggressive mode\n",
1681 				    __func__, wme->wme_hipri_traffic);
1682 				wme->wme_flags |= WME_F_AGGRMODE;
1683 				ieee80211_wme_updateparams_locked(ic);
1684 				wme->wme_hipri_traffic = 0;
1685 			} else
1686 				wme->wme_hipri_traffic =
1687 					wme->wme_hipri_switch_hysteresis;
1688 		}
1689 		if (ic->ic_flags & IEEE80211_F_WMEUPDATE) {
1690 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
1691 			ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1692 		}
1693 	}
1694 
1695 #ifndef IEEE80211_NO_HOSTAP
1696 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {	/* NB: no IBSS support*/
1697 		struct ieee80211_tim_ie *tie =
1698 			(struct ieee80211_tim_ie *) bo->bo_tim;
1699 		if (ic->ic_flags & IEEE80211_F_TIMUPDATE) {
1700 			u_int timlen, timoff, i;
1701 			/*
1702 			 * ATIM/DTIM needs updating.  If it fits in the
1703 			 * current space allocated then just copy in the
1704 			 * new bits.  Otherwise we need to move any trailing
1705 			 * data to make room.  Note that we know there is
1706 			 * contiguous space because ieee80211_beacon_allocate
1707 			 * insures there is space in the mbuf to write a
1708 			 * maximal-size virtual bitmap (based on ic_max_aid).
1709 			 */
1710 			/*
1711 			 * Calculate the bitmap size and offset, copy any
1712 			 * trailer out of the way, and then copy in the
1713 			 * new bitmap and update the information element.
1714 			 * Note that the tim bitmap must contain at least
1715 			 * one byte and any offset must be even.
1716 			 */
1717 			if (ic->ic_ps_pending != 0) {
1718 				timoff = 128;		/* impossibly large */
1719 				for (i = 0; i < ic->ic_tim_len; i++)
1720 					if (ic->ic_tim_bitmap[i]) {
1721 						timoff = i &~ 1;
1722 						break;
1723 					}
1724 				IASSERT(timoff != 128, ("tim bitmap empty!"));
1725 				for (i = ic->ic_tim_len-1; i >= timoff; i--)
1726 					if (ic->ic_tim_bitmap[i])
1727 						break;
1728 				timlen = 1 + (i - timoff);
1729 			} else {
1730 				timoff = 0;
1731 				timlen = 1;
1732 			}
1733 			if (timlen != bo->bo_tim_len) {
1734 				/* copy up/down trailer */
1735 				ovbcopy(bo->bo_trailer, tie->tim_bitmap+timlen,
1736 					bo->bo_trailer_len);
1737 				bo->bo_trailer = tie->tim_bitmap+timlen;
1738 				bo->bo_wme = bo->bo_trailer;
1739 				bo->bo_tim_len = timlen;
1740 
1741 				/* update information element */
1742 				tie->tim_len = 3 + timlen;
1743 				tie->tim_bitctl = timoff;
1744 				len_changed = 1;
1745 			}
1746 			memcpy(tie->tim_bitmap, ic->ic_tim_bitmap + timoff,
1747 				bo->bo_tim_len);
1748 
1749 			ic->ic_flags &= ~IEEE80211_F_TIMUPDATE;
1750 
1751 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1752 				"%s: TIM updated, pending %u, off %u, len %u\n",
1753 				__func__, ic->ic_ps_pending, timoff, timlen);
1754 		}
1755 		/* count down DTIM period */
1756 		if (tie->tim_count == 0)
1757 			tie->tim_count = tie->tim_period - 1;
1758 		else
1759 			tie->tim_count--;
1760 		/* update state for buffered multicast frames on DTIM */
1761 		if (mcast && (tie->tim_count == 1 || tie->tim_period == 1))
1762 			tie->tim_bitctl |= 1;
1763 		else
1764 			tie->tim_bitctl &= ~1;
1765 	}
1766 #endif /* !IEEE80211_NO_HOSTAP */
1767 	IEEE80211_BEACON_UNLOCK(ic);
1768 
1769 	return len_changed;
1770 }
1771 
1772 /*
1773  * Save an outbound packet for a node in power-save sleep state.
1774  * The new packet is placed on the node's saved queue, and the TIM
1775  * is changed, if necessary.
1776  */
1777 void
1778 ieee80211_pwrsave(struct ieee80211com *ic, struct ieee80211_node *ni,
1779 		  struct mbuf *m)
1780 {
1781 	int qlen, age;
1782 
1783 	IEEE80211_NODE_SAVEQ_LOCK(ni);
1784 	if (IF_QFULL(&ni->ni_savedq)) {
1785 		IF_DROP(&ni->ni_savedq);
1786 		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1787 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1788 			"[%s] pwr save q overflow, drops %d (size %d)\n",
1789 			ether_sprintf(ni->ni_macaddr),
1790 			ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE);
1791 #ifdef IEEE80211_DEBUG
1792 		if (ieee80211_msg_dumppkts(ic))
1793 			ieee80211_dump_pkt(mtod(m, caddr_t), m->m_len, -1, -1);
1794 #endif
1795 		m_freem(m);
1796 		return;
1797 	}
1798 	/*
1799 	 * Tag the frame with it's expiry time and insert
1800 	 * it in the queue.  The aging interval is 4 times
1801 	 * the listen interval specified by the station.
1802 	 * Frames that sit around too long are reclaimed
1803 	 * using this information.
1804 	 */
1805 	/* XXX handle overflow? */
1806 	age = ((ni->ni_intval * ic->ic_lintval) << 2) / 1024; /* TU -> secs */
1807 	_IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age);
1808 	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1809 
1810 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1811 		"[%s] save frame, %u now queued\n",
1812 		ether_sprintf(ni->ni_macaddr), qlen);
1813 
1814 	if (qlen == 1)
1815 		ic->ic_set_tim(ic, ni, 1);
1816 }
1817