xref: /netbsd-src/sys/net80211/ieee80211_output.c (revision 946379e7b37692fc43f68eb0d1c10daa0a7f3b6c)
1 /*	$NetBSD: ieee80211_output.c,v 1.53 2015/08/24 22:21:26 pooka 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 1.34 2005/08/10 16:22:29 sam Exp $");
37 #endif
38 #ifdef __NetBSD__
39 __KERNEL_RCSID(0, "$NetBSD: ieee80211_output.c,v 1.53 2015/08/24 22:21:26 pooka Exp $");
40 #endif
41 
42 #ifdef _KERNEL_OPT
43 #include "opt_inet.h"
44 #endif
45 
46 #ifdef __NetBSD__
47 #endif /* __NetBSD__ */
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/mbuf.h>
52 #include <sys/kernel.h>
53 #include <sys/endian.h>
54 #include <sys/errno.h>
55 #include <sys/proc.h>
56 #include <sys/sysctl.h>
57 
58 #include <net/if.h>
59 #include <net/if_llc.h>
60 #include <net/if_media.h>
61 #include <net/if_arp.h>
62 #include <net/if_ether.h>
63 #include <net/if_llc.h>
64 #include <net/if_vlanvar.h>
65 
66 #include <net80211/ieee80211_netbsd.h>
67 #include <net80211/ieee80211_var.h>
68 
69 #include <net/bpf.h>
70 
71 #ifdef INET
72 #include <netinet/in.h>
73 #include <netinet/in_systm.h>
74 #include <netinet/in_var.h>
75 #include <netinet/ip.h>
76 #include <net/if_ether.h>
77 #endif
78 
79 static int ieee80211_fragment(struct ieee80211com *, struct mbuf *,
80 	u_int hdrsize, u_int ciphdrsize, u_int mtu);
81 
82 #ifdef IEEE80211_DEBUG
83 /*
84  * Decide if an outbound management frame should be
85  * printed when debugging is enabled.  This filters some
86  * of the less interesting frames that come frequently
87  * (e.g. beacons).
88  */
89 static __inline int
90 doprint(struct ieee80211com *ic, int subtype)
91 {
92 	switch (subtype) {
93 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
94 		return (ic->ic_opmode == IEEE80211_M_IBSS);
95 	}
96 	return 1;
97 }
98 #endif
99 
100 /*
101  * Set the direction field and address fields of an outgoing
102  * non-QoS frame.  Note this should be called early on in
103  * constructing a frame as it sets i_fc[1]; other bits can
104  * then be or'd in.
105  */
106 static void
107 ieee80211_send_setup(struct ieee80211com *ic,
108 	struct ieee80211_node *ni,
109 	struct ieee80211_frame *wh,
110 	int type,
111 	const u_int8_t sa[IEEE80211_ADDR_LEN],
112 	const u_int8_t da[IEEE80211_ADDR_LEN],
113 	const u_int8_t bssid[IEEE80211_ADDR_LEN])
114 {
115 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
116 
117 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
118 	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
119 		switch (ic->ic_opmode) {
120 		case IEEE80211_M_STA:
121 			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
122 			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
123 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
124 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
125 			break;
126 		case IEEE80211_M_IBSS:
127 		case IEEE80211_M_AHDEMO:
128 			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
129 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
130 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
131 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
132 			break;
133 		case IEEE80211_M_HOSTAP:
134 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
135 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
136 			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
137 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
138 			break;
139 		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
140 			break;
141 		}
142 	} else {
143 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
144 		IEEE80211_ADDR_COPY(wh->i_addr1, da);
145 		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
146 		IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
147 	}
148 	*(u_int16_t *)&wh->i_dur[0] = 0;
149 	/* NB: use non-QoS tid */
150 	*(u_int16_t *)&wh->i_seq[0] =
151 	    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
152 	ni->ni_txseqs[0]++;
153 #undef WH4
154 }
155 
156 /*
157  * Send a management frame to the specified node.  The node pointer
158  * must have a reference as the pointer will be passed to the driver
159  * and potentially held for a long time.  If the frame is successfully
160  * dispatched to the driver, then it is responsible for freeing the
161  * reference (and potentially free'ing up any associated storage).
162  */
163 static int
164 ieee80211_mgmt_output(struct ieee80211com *ic, struct ieee80211_node *ni,
165     struct mbuf *m, int type, int timer)
166 {
167 	struct ifnet *ifp = ic->ic_ifp;
168 	struct ieee80211_frame *wh;
169 
170 	IASSERT(ni != NULL, ("null node"));
171 
172 	/*
173 	 * Yech, hack alert!  We want to pass the node down to the
174 	 * driver's start routine.  If we don't do so then the start
175 	 * routine must immediately look it up again and that can
176 	 * cause a lock order reversal if, for example, this frame
177 	 * is being sent because the station is being timedout and
178 	 * the frame being sent is a DEAUTH message.  We could stick
179 	 * this in an m_tag and tack that on to the mbuf.  However
180 	 * that's rather expensive to do for every frame so instead
181 	 * we stuff it in the rcvif field since outbound frames do
182 	 * not (presently) use this.
183 	 */
184 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
185 	if (m == NULL)
186 		return ENOMEM;
187 #ifdef __FreeBSD__
188 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
189 #endif
190 	m->m_pkthdr.rcvif = (void *)ni;
191 
192 	wh = mtod(m, struct ieee80211_frame *);
193 	ieee80211_send_setup(ic, ni, wh,
194 		IEEE80211_FC0_TYPE_MGT | type,
195 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
196 	if ((m->m_flags & M_LINK0) != 0 && ni->ni_challenge != NULL) {
197 		m->m_flags &= ~M_LINK0;
198 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
199 			"[%s] encrypting frame (%s)\n",
200 			ether_sprintf(wh->i_addr1), __func__);
201 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
202 	}
203 #ifdef IEEE80211_DEBUG
204 	/* avoid printing too many frames */
205 	if ((ieee80211_msg_debug(ic) && doprint(ic, type)) ||
206 	    ieee80211_msg_dumppkts(ic)) {
207 		printf("[%s] send %s on channel %u\n",
208 		    ether_sprintf(wh->i_addr1),
209 		    ieee80211_mgt_subtype_name[
210 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
211 				IEEE80211_FC0_SUBTYPE_SHIFT],
212 		    ieee80211_chan2ieee(ic, ic->ic_curchan));
213 	}
214 #endif
215 	IEEE80211_NODE_STAT(ni, tx_mgmt);
216 	IF_ENQUEUE(&ic->ic_mgtq, m);
217 	if (timer) {
218 		/*
219 		 * Set the mgt frame timeout.
220 		 */
221 		ic->ic_mgt_timer = timer;
222 		ifp->if_timer = 1;
223 	}
224 	(*ifp->if_start)(ifp);
225 	return 0;
226 }
227 
228 /*
229  * Send a null data frame to the specified node.
230  *
231  * NB: the caller is assumed to have setup a node reference
232  *     for use; this is necessary to deal with a race condition
233  *     when probing for inactive stations.
234  */
235 int
236 ieee80211_send_nulldata(struct ieee80211_node *ni)
237 {
238 	struct ieee80211com *ic = ni->ni_ic;
239 	struct ifnet *ifp = ic->ic_ifp;
240 	struct mbuf *m;
241 	struct ieee80211_frame *wh;
242 
243 	MGETHDR(m, M_NOWAIT, MT_HEADER);
244 	if (m == NULL) {
245 		/* XXX debug msg */
246 		ic->ic_stats.is_tx_nobuf++;
247 		ieee80211_unref_node(&ni);
248 		return ENOMEM;
249 	}
250 	m->m_pkthdr.rcvif = (void *) ni;
251 
252 	wh = mtod(m, struct ieee80211_frame *);
253 	ieee80211_send_setup(ic, ni, wh,
254 		IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
255 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
256 	/* NB: power management bit is never sent by an AP */
257 	if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
258 	    ic->ic_opmode != IEEE80211_M_HOSTAP)
259 		wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
260 	m->m_len = m->m_pkthdr.len = sizeof(struct ieee80211_frame);
261 
262 	IEEE80211_NODE_STAT(ni, tx_data);
263 
264 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
265 	    "[%s] send null data frame on channel %u, pwr mgt %s\n",
266 	    ether_sprintf(ni->ni_macaddr),
267 	    ieee80211_chan2ieee(ic, ic->ic_curchan),
268 	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");
269 
270 	IF_ENQUEUE(&ic->ic_mgtq, m);		/* cheat */
271 	(*ifp->if_start)(ifp);
272 
273 	return 0;
274 }
275 
276 /*
277  * Assign priority to a frame based on any vlan tag assigned
278  * to the station and/or any Diffserv setting in an IP header.
279  * Finally, if an ACM policy is setup (in station mode) it's
280  * applied.
281  */
282 int
283 ieee80211_classify(struct ieee80211com *ic, struct mbuf *m, struct ieee80211_node *ni)
284 {
285 	int v_wme_ac, d_wme_ac, ac;
286 #ifdef INET
287 	struct ether_header *eh;
288 #endif
289 
290 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
291 		ac = WME_AC_BE;
292 		goto done;
293 	}
294 
295 	/*
296 	 * If node has a vlan tag then all traffic
297 	 * to it must have a matching tag.
298 	 */
299 	v_wme_ac = 0;
300 	if (ni->ni_vlan != 0) {
301 		/* XXX used to check ec_nvlans. */
302 		struct m_tag *mtag = m_tag_find(m, PACKET_TAG_VLAN, NULL);
303 		if (mtag == NULL) {
304 			IEEE80211_NODE_STAT(ni, tx_novlantag);
305 			return 1;
306 		}
307 		if (EVL_VLANOFTAG(VLAN_TAG_VALUE(mtag)) !=
308 		    EVL_VLANOFTAG(ni->ni_vlan)) {
309 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
310 			return 1;
311 		}
312 		/* map vlan priority to AC */
313 		switch (EVL_PRIOFTAG(ni->ni_vlan)) {
314 		case 1:
315 		case 2:
316 			v_wme_ac = WME_AC_BK;
317 			break;
318 		case 0:
319 		case 3:
320 			v_wme_ac = WME_AC_BE;
321 			break;
322 		case 4:
323 		case 5:
324 			v_wme_ac = WME_AC_VI;
325 			break;
326 		case 6:
327 		case 7:
328 			v_wme_ac = WME_AC_VO;
329 			break;
330 		}
331 	}
332 
333 #ifdef INET
334 	eh = mtod(m, struct ether_header *);
335 	if (eh->ether_type == htons(ETHERTYPE_IP)) {
336 		const struct ip *ip = (struct ip *)
337 			(mtod(m, u_int8_t *) + sizeof (*eh));
338 		/*
339 		 * IP frame, map the TOS field.
340 		 */
341 		switch (ip->ip_tos) {
342 		case 0x08:
343 		case 0x20:
344 			d_wme_ac = WME_AC_BK;	/* background */
345 			break;
346 		case 0x28:
347 		case 0xa0:
348 			d_wme_ac = WME_AC_VI;	/* video */
349 			break;
350 		case 0x30:			/* voice */
351 		case 0xe0:
352 		case 0x88:			/* XXX UPSD */
353 		case 0xb8:
354 			d_wme_ac = WME_AC_VO;
355 			break;
356 		default:
357 			d_wme_ac = WME_AC_BE;
358 			break;
359 		}
360 	} else {
361 #endif /* INET */
362 		d_wme_ac = WME_AC_BE;
363 #ifdef INET
364 	}
365 #endif
366 	/*
367 	 * Use highest priority AC.
368 	 */
369 	if (v_wme_ac > d_wme_ac)
370 		ac = v_wme_ac;
371 	else
372 		ac = d_wme_ac;
373 
374 	/*
375 	 * Apply ACM policy.
376 	 */
377 	if (ic->ic_opmode == IEEE80211_M_STA) {
378 		static const int acmap[4] = {
379 			WME_AC_BK,	/* WME_AC_BE */
380 			WME_AC_BK,	/* WME_AC_BK */
381 			WME_AC_BE,	/* WME_AC_VI */
382 			WME_AC_VI,	/* WME_AC_VO */
383 		};
384 		while (ac != WME_AC_BK &&
385 		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
386 			ac = acmap[ac];
387 	}
388 done:
389 	M_WME_SETAC(m, ac);
390 	return 0;
391 }
392 
393 /*
394  * Insure there is sufficient contiguous space to encapsulate the
395  * 802.11 data frame.  If room isn't already there, arrange for it.
396  * Drivers and cipher modules assume we have done the necessary work
397  * and fail rudely if they don't find the space they need.
398  */
399 static struct mbuf *
400 ieee80211_mbuf_adjust(struct ieee80211com *ic, int hdrsize,
401 	struct ieee80211_key *key, struct mbuf *m)
402 {
403 #define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
404 	int needed_space = hdrsize;
405 	int wlen = 0;
406 
407 	if (key != NULL) {
408 		/* XXX belongs in crypto code? */
409 		needed_space += key->wk_cipher->ic_header;
410 		/* XXX frags */
411 	}
412 	/*
413 	 * We know we are called just before stripping an Ethernet
414 	 * header and prepending an LLC header.  This means we know
415 	 * there will be
416 	 *	sizeof(struct ether_header) - sizeof(struct llc)
417 	 * bytes recovered to which we need additional space for the
418 	 * 802.11 header and any crypto header.
419 	 */
420 	/* XXX check trailing space and copy instead? */
421 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
422 		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
423 		if (n == NULL) {
424 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
425 			    "%s: cannot expand storage\n", __func__);
426 			ic->ic_stats.is_tx_nobuf++;
427 			m_freem(m);
428 			return NULL;
429 		}
430 		IASSERT(needed_space <= MHLEN,
431 		    ("not enough room, need %u got %zu\n", needed_space, MHLEN));
432 		/*
433 		 * Setup new mbuf to have leading space to prepend the
434 		 * 802.11 header and any crypto header bits that are
435 		 * required (the latter are added when the driver calls
436 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
437 		 */
438 		/* NB: must be first 'cuz it clobbers m_data */
439 		M_MOVE_PKTHDR(n, m);
440 		n->m_len = 0;			/* NB: m_gethdr does not set */
441 		n->m_data += needed_space;
442 		/*
443 		 * Pull up Ethernet header to create the expected layout.
444 		 * We could use m_pullup but that's overkill (i.e. we don't
445 		 * need the actual data) and it cannot fail so do it inline
446 		 * for speed.
447 		 */
448 		/* NB: struct ether_header is known to be contiguous */
449 		n->m_len += sizeof(struct ether_header);
450 		m->m_len -= sizeof(struct ether_header);
451 		m->m_data += sizeof(struct ether_header);
452 		/*
453 		 * Replace the head of the chain.
454 		 */
455 		n->m_next = m;
456 		m = n;
457 	} else {
458                 /* We will overwrite the ethernet header in the
459                  * 802.11 encapsulation stage.  Make sure that it
460                  * is writable.
461 		 */
462 		wlen = sizeof(struct ether_header);
463 	}
464 
465 	/*
466 	 * If we're going to s/w encrypt the mbuf chain make sure it is
467 	 * writable.
468 	 */
469 	if (key != NULL && (key->wk_flags & IEEE80211_KEY_SWCRYPT) != 0)
470 		wlen = M_COPYALL;
471 
472 	if (wlen != 0 && m_makewritable(&m, 0, wlen, M_DONTWAIT) != 0) {
473 		m_freem(m);
474 		return NULL;
475 	}
476 	return m;
477 #undef TO_BE_RECLAIMED
478 }
479 
480 /*
481  * Return the transmit key to use in sending a unicast frame.
482  * If a unicast key is set we use that.  When no unicast key is set
483  * we fall back to the default transmit key.
484  */
485 static __inline struct ieee80211_key *
486 ieee80211_crypto_getucastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
487 {
488 	if (IEEE80211_KEY_UNDEFINED(ni->ni_ucastkey)) {
489 		if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
490 		    IEEE80211_KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
491 			return NULL;
492 		return &ic->ic_nw_keys[ic->ic_def_txkey];
493 	} else {
494 		return &ni->ni_ucastkey;
495 	}
496 }
497 
498 /*
499  * Return the transmit key to use in sending a multicast frame.
500  * Multicast traffic always uses the group key which is installed as
501  * the default tx key.
502  */
503 static __inline struct ieee80211_key *
504 ieee80211_crypto_getmcastkey(struct ieee80211com *ic,
505     struct ieee80211_node *ni)
506 {
507 	if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
508 	    IEEE80211_KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
509 		return NULL;
510 	return &ic->ic_nw_keys[ic->ic_def_txkey];
511 }
512 
513 /*
514  * Encapsulate an outbound data frame.  The mbuf chain is updated.
515  * If an error is encountered NULL is returned.  The caller is required
516  * to provide a node reference and pullup the ethernet header in the
517  * first mbuf.
518  */
519 struct mbuf *
520 ieee80211_encap(struct ieee80211com *ic, struct mbuf *m,
521 	struct ieee80211_node *ni)
522 {
523 	struct ether_header eh;
524 	struct ieee80211_frame *wh;
525 	struct ieee80211_key *key;
526 	struct llc *llc;
527 	int hdrsize, datalen, addqos, txfrag;
528 
529 	IASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
530 	memcpy(&eh, mtod(m, void *), sizeof(struct ether_header));
531 
532 	/*
533 	 * Insure space for additional headers.  First identify
534 	 * transmit key to use in calculating any buffer adjustments
535 	 * required.  This is also used below to do privacy
536 	 * encapsulation work.  Then calculate the 802.11 header
537 	 * size and any padding required by the driver.
538 	 *
539 	 * Note key may be NULL if we fall back to the default
540 	 * transmit key and that is not set.  In that case the
541 	 * buffer may not be expanded as needed by the cipher
542 	 * routines, but they will/should discard it.
543 	 */
544 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
545 		if (ic->ic_opmode == IEEE80211_M_STA ||
546 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost))
547 			key = ieee80211_crypto_getucastkey(ic, ni);
548 		else
549 			key = ieee80211_crypto_getmcastkey(ic, ni);
550 		if (key == NULL && eh.ether_type != htons(ETHERTYPE_PAE)) {
551 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
552 			    "[%s] no default transmit key (%s) deftxkey %u\n",
553 			    ether_sprintf(eh.ether_dhost), __func__,
554 			    ic->ic_def_txkey);
555 			ic->ic_stats.is_tx_nodefkey++;
556 		}
557 	} else
558 		key = NULL;
559 	/* XXX 4-address format */
560 	/*
561 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
562 	 * frames so suppress use.  This may be an issue if other
563 	 * ap's require all data frames to be QoS-encapsulated
564 	 * once negotiated in which case we'll need to make this
565 	 * configurable.
566 	 */
567 	addqos = (ni->ni_flags & IEEE80211_NODE_QOS) &&
568 		 eh.ether_type != htons(ETHERTYPE_PAE);
569 	if (addqos)
570 		hdrsize = sizeof(struct ieee80211_qosframe);
571 	else
572 		hdrsize = sizeof(struct ieee80211_frame);
573 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
574 		hdrsize = roundup(hdrsize, sizeof(u_int32_t));
575 	m = ieee80211_mbuf_adjust(ic, hdrsize, key, m);
576 	if (m == NULL) {
577 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
578 		goto bad;
579 	}
580 
581 	/* NB: this could be optimized because of ieee80211_mbuf_adjust */
582 	m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
583 	llc = mtod(m, struct llc *);
584 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
585 	llc->llc_control = LLC_UI;
586 	llc->llc_snap.org_code[0] = 0;
587 	llc->llc_snap.org_code[1] = 0;
588 	llc->llc_snap.org_code[2] = 0;
589 	llc->llc_snap.ether_type = eh.ether_type;
590 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
591 
592 	M_PREPEND(m, hdrsize, M_DONTWAIT);
593 	if (m == NULL) {
594 		ic->ic_stats.is_tx_nobuf++;
595 		goto bad;
596 	}
597 	wh = mtod(m, struct ieee80211_frame *);
598 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
599 	*(u_int16_t *)wh->i_dur = 0;
600 	switch (ic->ic_opmode) {
601 	case IEEE80211_M_STA:
602 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
603 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
604 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
605 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
606 		break;
607 	case IEEE80211_M_IBSS:
608 	case IEEE80211_M_AHDEMO:
609 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
610 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
611 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
612 		/*
613 		 * NB: always use the bssid from ic_bss as the
614 		 *     neighbor's may be stale after an ibss merge
615 		 */
616 		IEEE80211_ADDR_COPY(wh->i_addr3, ic->ic_bss->ni_bssid);
617 		break;
618 	case IEEE80211_M_HOSTAP:
619 #ifndef IEEE80211_NO_HOSTAP
620 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
621 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
622 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
623 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
624 #endif /* !IEEE80211_NO_HOSTAP */
625 		break;
626 	case IEEE80211_M_MONITOR:
627 		goto bad;
628 	}
629 	if (m->m_flags & M_MORE_DATA)
630 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
631 	if (addqos) {
632 		struct ieee80211_qosframe *qwh =
633 			(struct ieee80211_qosframe *) wh;
634 		int ac, tid;
635 
636 		ac = M_WME_GETAC(m);
637 		/* map from access class/queue to 11e header priorty value */
638 		tid = WME_AC_TO_TID(ac);
639 		qwh->i_qos[0] = tid & IEEE80211_QOS_TID;
640 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
641 			qwh->i_qos[0] |= 1 << IEEE80211_QOS_ACKPOLICY_S;
642 		qwh->i_qos[1] = 0;
643 		qwh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
644 
645 		*(u_int16_t *)wh->i_seq =
646 		    htole16(ni->ni_txseqs[tid] << IEEE80211_SEQ_SEQ_SHIFT);
647 		ni->ni_txseqs[tid]++;
648 	} else {
649 		*(u_int16_t *)wh->i_seq =
650 		    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
651 		ni->ni_txseqs[0]++;
652 	}
653 	/* check if xmit fragmentation is required */
654 	txfrag = (m->m_pkthdr.len > ic->ic_fragthreshold &&
655 	    !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
656 	    (m->m_flags & M_FF) == 0);          /* NB: don't fragment ff's */
657 	if (key != NULL) {
658 		/*
659 		 * IEEE 802.1X: send EAPOL frames always in the clear.
660 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
661 		 */
662 		if (eh.ether_type != htons(ETHERTYPE_PAE) ||
663 		    ((ic->ic_flags & IEEE80211_F_WPA) &&
664 		     (ic->ic_opmode == IEEE80211_M_STA ?
665 		      !IEEE80211_KEY_UNDEFINED(*key) :
666 		      !IEEE80211_KEY_UNDEFINED(ni->ni_ucastkey)))) {
667 			wh->i_fc[1] |= IEEE80211_FC1_WEP;
668 			if (!ieee80211_crypto_enmic(ic, key, m, txfrag)) {
669 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
670 				    "[%s] enmic failed, discard frame\n",
671 				    ether_sprintf(eh.ether_dhost));
672 				ic->ic_stats.is_crypto_enmicfail++;
673 				goto bad;
674 			}
675 		}
676 	}
677 	if (txfrag && !ieee80211_fragment(ic, m, hdrsize,
678 	    key != NULL ? key->wk_cipher->ic_header : 0, ic->ic_fragthreshold))
679 		goto bad;
680 
681 	IEEE80211_NODE_STAT(ni, tx_data);
682 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);
683 
684 	return m;
685 bad:
686 	if (m != NULL)
687 		m_freem(m);
688 	return NULL;
689 }
690 
691 /*
692  * Arguments in:
693  *
694  * paylen:  payload length (no FCS, no WEP header)
695  *
696  * hdrlen:  header length
697  *
698  * rate:    MSDU speed, units 500kb/s
699  *
700  * flags:   IEEE80211_F_SHPREAMBLE (use short preamble),
701  *          IEEE80211_F_SHSLOT (use short slot length)
702  *
703  * Arguments out:
704  *
705  * d:       802.11 Duration field for RTS,
706  *          802.11 Duration field for data frame,
707  *          PLCP Length for data frame,
708  *          residual octets at end of data slot
709  */
710 static int
711 ieee80211_compute_duration1(int len, int use_ack, uint32_t icflags, int rate,
712     struct ieee80211_duration *d)
713 {
714 	int pre, ctsrate;
715 	int ack, bitlen, data_dur, remainder;
716 
717 	/* RTS reserves medium for SIFS | CTS | SIFS | (DATA) | SIFS | ACK
718 	 * DATA reserves medium for SIFS | ACK,
719 	 *
720 	 * (XXX or SIFS | ACK | SIFS | DATA | SIFS | ACK, if more fragments)
721 	 *
722 	 * XXXMYC: no ACK on multicast/broadcast or control packets
723 	 */
724 
725 	bitlen = len * 8;
726 
727 	pre = IEEE80211_DUR_DS_SIFS;
728 	if ((icflags & IEEE80211_F_SHPREAMBLE) != 0)
729 		pre += IEEE80211_DUR_DS_SHORT_PREAMBLE + IEEE80211_DUR_DS_FAST_PLCPHDR;
730 	else
731 		pre += IEEE80211_DUR_DS_LONG_PREAMBLE + IEEE80211_DUR_DS_SLOW_PLCPHDR;
732 
733 	d->d_residue = 0;
734 	data_dur = (bitlen * 2) / rate;
735 	remainder = (bitlen * 2) % rate;
736 	if (remainder != 0) {
737 		d->d_residue = (rate - remainder) / 16;
738 		data_dur++;
739 	}
740 
741 	switch (rate) {
742 	case 2:		/* 1 Mb/s */
743 	case 4:		/* 2 Mb/s */
744 		/* 1 - 2 Mb/s WLAN: send ACK/CTS at 1 Mb/s */
745 		ctsrate = 2;
746 		break;
747 	case 11:	/* 5.5 Mb/s */
748 	case 22:	/* 11  Mb/s */
749 	case 44:	/* 22  Mb/s */
750 		/* 5.5 - 11 Mb/s WLAN: send ACK/CTS at 2 Mb/s */
751 		ctsrate = 4;
752 		break;
753 	default:
754 		/* TBD */
755 		return -1;
756 	}
757 
758 	d->d_plcp_len = data_dur;
759 
760 	ack = (use_ack) ? pre + (IEEE80211_DUR_DS_SLOW_ACK * 2) / ctsrate : 0;
761 
762 	d->d_rts_dur =
763 	    pre + (IEEE80211_DUR_DS_SLOW_CTS * 2) / ctsrate +
764 	    pre + data_dur +
765 	    ack;
766 
767 	d->d_data_dur = ack;
768 
769 	return 0;
770 }
771 
772 /*
773  * Arguments in:
774  *
775  * wh:      802.11 header
776  *
777  * paylen:  payload length (no FCS, no WEP header)
778  *
779  * rate:    MSDU speed, units 500kb/s
780  *
781  * fraglen: fragment length, set to maximum (or higher) for no
782  *          fragmentation
783  *
784  * flags:   IEEE80211_F_PRIVACY (hardware adds WEP),
785  *          IEEE80211_F_SHPREAMBLE (use short preamble),
786  *          IEEE80211_F_SHSLOT (use short slot length)
787  *
788  * Arguments out:
789  *
790  * d0: 802.11 Duration fields (RTS/Data), PLCP Length, Service fields
791  *     of first/only fragment
792  *
793  * dn: 802.11 Duration fields (RTS/Data), PLCP Length, Service fields
794  *     of last fragment
795  *
796  * ieee80211_compute_duration assumes crypto-encapsulation, if any,
797  * has already taken place.
798  */
799 int
800 ieee80211_compute_duration(const struct ieee80211_frame_min *wh,
801     const struct ieee80211_key *wk, int len,
802     uint32_t icflags, int fraglen, int rate, struct ieee80211_duration *d0,
803     struct ieee80211_duration *dn, int *npktp, int debug)
804 {
805 	int ack, rc;
806 	int cryptolen,	/* crypto overhead: header+trailer */
807 	    firstlen,	/* first fragment's payload + overhead length */
808 	    hdrlen,	/* header length w/o driver padding */
809 	    lastlen,	/* last fragment's payload length w/ overhead */
810 	    lastlen0,	/* last fragment's payload length w/o overhead */
811 	    npkt,	/* number of fragments */
812 	    overlen,	/* non-802.11 header overhead per fragment */
813 	    paylen;	/* payload length w/o overhead */
814 
815 	hdrlen = ieee80211_anyhdrsize((const void *)wh);
816 
817         /* Account for padding required by the driver. */
818 	if (icflags & IEEE80211_F_DATAPAD)
819 		paylen = len - roundup(hdrlen, sizeof(u_int32_t));
820 	else
821 		paylen = len - hdrlen;
822 
823 	overlen = IEEE80211_CRC_LEN;
824 
825 	if (wk != NULL) {
826 		cryptolen = wk->wk_cipher->ic_header +
827 		            wk->wk_cipher->ic_trailer;
828 		paylen -= cryptolen;
829 		overlen += cryptolen;
830 	}
831 
832 	npkt = paylen / fraglen;
833 	lastlen0 = paylen % fraglen;
834 
835 	if (npkt == 0)			/* no fragments */
836 		lastlen = paylen + overlen;
837 	else if (lastlen0 != 0) {	/* a short "tail" fragment */
838 		lastlen = lastlen0 + overlen;
839 		npkt++;
840 	} else				/* full-length "tail" fragment */
841 		lastlen = fraglen + overlen;
842 
843 	if (npktp != NULL)
844 		*npktp = npkt;
845 
846 	if (npkt > 1)
847 		firstlen = fraglen + overlen;
848 	else
849 		firstlen = paylen + overlen;
850 
851 	if (debug) {
852 		printf("%s: npkt %d firstlen %d lastlen0 %d lastlen %d "
853 		    "fraglen %d overlen %d len %d rate %d icflags %08x\n",
854 		    __func__, npkt, firstlen, lastlen0, lastlen, fraglen,
855 		    overlen, len, rate, icflags);
856 	}
857 
858 	ack = !IEEE80211_IS_MULTICAST(wh->i_addr1) &&
859 	    (wh->i_fc[1] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL;
860 
861 	rc = ieee80211_compute_duration1(firstlen + hdrlen,
862 	    ack, icflags, rate, d0);
863 	if (rc == -1)
864 		return rc;
865 
866 	if (npkt <= 1) {
867 		*dn = *d0;
868 		return 0;
869 	}
870 	return ieee80211_compute_duration1(lastlen + hdrlen, ack, icflags, rate,
871 	    dn);
872 }
873 
874 /*
875  * Fragment the frame according to the specified mtu.
876  * The size of the 802.11 header (w/o padding) is provided
877  * so we don't need to recalculate it.  We create a new
878  * mbuf for each fragment and chain it through m_nextpkt;
879  * we might be able to optimize this by reusing the original
880  * packet's mbufs but that is significantly more complicated.
881  */
882 static int
883 ieee80211_fragment(struct ieee80211com *ic, struct mbuf *m0,
884 	u_int hdrsize, u_int ciphdrsize, u_int mtu)
885 {
886 	struct ieee80211_frame *wh, *whf;
887 	struct mbuf *m, *prev, *next;
888 	u_int totalhdrsize, fragno, fragsize, off, remainder, payload;
889 
890 	IASSERT(m0->m_nextpkt == NULL, ("mbuf already chained?"));
891 	IASSERT(m0->m_pkthdr.len > mtu,
892 		("pktlen %u mtu %u", m0->m_pkthdr.len, mtu));
893 
894 	wh = mtod(m0, struct ieee80211_frame *);
895 	/* NB: mark the first frag; it will be propagated below */
896 	wh->i_fc[1] |= IEEE80211_FC1_MORE_FRAG;
897 	totalhdrsize = hdrsize + ciphdrsize;
898 	fragno = 1;
899 	off = mtu - ciphdrsize;
900 	remainder = m0->m_pkthdr.len - off;
901 	prev = m0;
902 	do {
903 		fragsize = totalhdrsize + remainder;
904 		if (fragsize > mtu)
905 			fragsize = mtu;
906 		IASSERT(fragsize < MCLBYTES,
907 			("fragment size %u too big!", fragsize));
908 		if (fragsize > MHLEN)
909 			m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
910 		else
911 			m = m_gethdr(M_DONTWAIT, MT_DATA);
912 		if (m == NULL)
913 			goto bad;
914 		/* leave room to prepend any cipher header */
915 		m_align(m, fragsize - ciphdrsize);
916 
917 		/*
918 		 * Form the header in the fragment.  Note that since
919 		 * we mark the first fragment with the MORE_FRAG bit
920 		 * it automatically is propagated to each fragment; we
921 		 * need only clear it on the last fragment (done below).
922 		 */
923 		whf = mtod(m, struct ieee80211_frame *);
924 		memcpy(whf, wh, hdrsize);
925 		*(u_int16_t *)&whf->i_seq[0] |= htole16(
926 			(fragno & IEEE80211_SEQ_FRAG_MASK) <<
927 				IEEE80211_SEQ_FRAG_SHIFT);
928 		fragno++;
929 
930 		payload = fragsize - totalhdrsize;
931 		/* NB: destination is known to be contiguous */
932 		m_copydata(m0, off, payload, mtod(m, u_int8_t *) + hdrsize);
933 		m->m_len = hdrsize + payload;
934 		m->m_pkthdr.len = hdrsize + payload;
935 		m->m_flags |= M_FRAG;
936 
937 		/* chain up the fragment */
938 		prev->m_nextpkt = m;
939 		prev = m;
940 
941 		/* deduct fragment just formed */
942 		remainder -= payload;
943 		off += payload;
944 	} while (remainder != 0);
945 	whf->i_fc[1] &= ~IEEE80211_FC1_MORE_FRAG;
946 
947 	/* strip first mbuf now that everything has been copied */
948 	m_adj(m0, -(m0->m_pkthdr.len - (mtu - ciphdrsize)));
949 	m0->m_flags |= M_FIRSTFRAG | M_FRAG;
950 
951 	ic->ic_stats.is_tx_fragframes++;
952 	ic->ic_stats.is_tx_frags += fragno-1;
953 
954 	return 1;
955 bad:
956 	/* reclaim fragments but leave original frame for caller to free */
957 	for (m = m0->m_nextpkt; m != NULL; m = next) {
958 		next = m->m_nextpkt;
959 		m->m_nextpkt = NULL;            /* XXX paranoid */
960 		m_freem(m);
961 	}
962 	m0->m_nextpkt = NULL;
963 	return 0;
964 }
965 
966 /*
967  * Add a supported rates element id to a frame.
968  */
969 static u_int8_t *
970 ieee80211_add_rates(u_int8_t *frm, const struct ieee80211_rateset *rs)
971 {
972 	int nrates;
973 
974 	*frm++ = IEEE80211_ELEMID_RATES;
975 	nrates = rs->rs_nrates;
976 	if (nrates > IEEE80211_RATE_SIZE)
977 		nrates = IEEE80211_RATE_SIZE;
978 	*frm++ = nrates;
979 	memcpy(frm, rs->rs_rates, nrates);
980 	return frm + nrates;
981 }
982 
983 /*
984  * Add an extended supported rates element id to a frame.
985  */
986 static u_int8_t *
987 ieee80211_add_xrates(u_int8_t *frm, const struct ieee80211_rateset *rs)
988 {
989 	/*
990 	 * Add an extended supported rates element if operating in 11g mode.
991 	 */
992 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
993 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
994 		*frm++ = IEEE80211_ELEMID_XRATES;
995 		*frm++ = nrates;
996 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
997 		frm += nrates;
998 	}
999 	return frm;
1000 }
1001 
1002 /*
1003  * Add an ssid elemet to a frame.
1004  */
1005 static u_int8_t *
1006 ieee80211_add_ssid(u_int8_t *frm, const u_int8_t *ssid, u_int len)
1007 {
1008 	*frm++ = IEEE80211_ELEMID_SSID;
1009 	*frm++ = len;
1010 	memcpy(frm, ssid, len);
1011 	return frm + len;
1012 }
1013 
1014 /*
1015  * Add an erp element to a frame.
1016  */
1017 static u_int8_t *
1018 ieee80211_add_erp(u_int8_t *frm, struct ieee80211com *ic)
1019 {
1020 	u_int8_t erp;
1021 
1022 	*frm++ = IEEE80211_ELEMID_ERP;
1023 	*frm++ = 1;
1024 	erp = 0;
1025 	if (ic->ic_nonerpsta != 0)
1026 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
1027 	if (ic->ic_flags & IEEE80211_F_USEPROT)
1028 		erp |= IEEE80211_ERP_USE_PROTECTION;
1029 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
1030 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
1031 	*frm++ = erp;
1032 	return frm;
1033 }
1034 
1035 static u_int8_t *
1036 ieee80211_setup_wpa_ie(struct ieee80211com *ic, u_int8_t *ie)
1037 {
1038 #define	WPA_OUI_BYTES		0x00, 0x50, 0xf2
1039 #define	ADDSHORT(frm, v) do {			\
1040 	frm[0] = (v) & 0xff;			\
1041 	frm[1] = (v) >> 8;			\
1042 	frm += 2;				\
1043 } while (0)
1044 #define	ADDSELECTOR(frm, sel) do {		\
1045 	memcpy(frm, sel, 4);			\
1046 	frm += 4;				\
1047 } while (0)
1048 	static const u_int8_t oui[4] = { WPA_OUI_BYTES, WPA_OUI_TYPE };
1049 	static const u_int8_t cipher_suite[][4] = {
1050 		{ WPA_OUI_BYTES, WPA_CSE_WEP40 },	/* NB: 40-bit */
1051 		{ WPA_OUI_BYTES, WPA_CSE_TKIP },
1052 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX WRAP */
1053 		{ WPA_OUI_BYTES, WPA_CSE_CCMP },
1054 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
1055 		{ WPA_OUI_BYTES, WPA_CSE_NULL },
1056 	};
1057 	static const u_int8_t wep104_suite[4] =
1058 		{ WPA_OUI_BYTES, WPA_CSE_WEP104 };
1059 	static const u_int8_t key_mgt_unspec[4] =
1060 		{ WPA_OUI_BYTES, WPA_ASE_8021X_UNSPEC };
1061 	static const u_int8_t key_mgt_psk[4] =
1062 		{ WPA_OUI_BYTES, WPA_ASE_8021X_PSK };
1063 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
1064 	u_int8_t *frm = ie;
1065 	u_int8_t *selcnt;
1066 
1067 	*frm++ = IEEE80211_ELEMID_VENDOR;
1068 	*frm++ = 0;				/* length filled in below */
1069 	memcpy(frm, oui, sizeof(oui));		/* WPA OUI */
1070 	frm += sizeof(oui);
1071 	ADDSHORT(frm, WPA_VERSION);
1072 
1073 	/* XXX filter out CKIP */
1074 
1075 	/* multicast cipher */
1076 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
1077 	    rsn->rsn_mcastkeylen >= 13)
1078 		ADDSELECTOR(frm, wep104_suite);
1079 	else
1080 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
1081 
1082 	/* unicast cipher list */
1083 	selcnt = frm;
1084 	ADDSHORT(frm, 0);			/* selector count */
1085 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
1086 		selcnt[0]++;
1087 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
1088 	}
1089 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
1090 		selcnt[0]++;
1091 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
1092 	}
1093 
1094 	/* authenticator selector list */
1095 	selcnt = frm;
1096 	ADDSHORT(frm, 0);			/* selector count */
1097 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
1098 		selcnt[0]++;
1099 		ADDSELECTOR(frm, key_mgt_unspec);
1100 	}
1101 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
1102 		selcnt[0]++;
1103 		ADDSELECTOR(frm, key_mgt_psk);
1104 	}
1105 
1106 	/* optional capabilities */
1107 	if (rsn->rsn_caps != 0 && rsn->rsn_caps != RSN_CAP_PREAUTH)
1108 		ADDSHORT(frm, rsn->rsn_caps);
1109 
1110 	/* calculate element length */
1111 	ie[1] = frm - ie - 2;
1112 	IASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
1113 		("WPA IE too big, %u > %zu",
1114 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
1115 	return frm;
1116 #undef ADDSHORT
1117 #undef ADDSELECTOR
1118 #undef WPA_OUI_BYTES
1119 }
1120 
1121 static u_int8_t *
1122 ieee80211_setup_rsn_ie(struct ieee80211com *ic, u_int8_t *ie)
1123 {
1124 #define	RSN_OUI_BYTES		0x00, 0x0f, 0xac
1125 #define	ADDSHORT(frm, v) do {			\
1126 	frm[0] = (v) & 0xff;			\
1127 	frm[1] = (v) >> 8;			\
1128 	frm += 2;				\
1129 } while (0)
1130 #define	ADDSELECTOR(frm, sel) do {		\
1131 	memcpy(frm, sel, 4);			\
1132 	frm += 4;				\
1133 } while (0)
1134 	static const u_int8_t cipher_suite[][4] = {
1135 		{ RSN_OUI_BYTES, RSN_CSE_WEP40 },	/* NB: 40-bit */
1136 		{ RSN_OUI_BYTES, RSN_CSE_TKIP },
1137 		{ RSN_OUI_BYTES, RSN_CSE_WRAP },
1138 		{ RSN_OUI_BYTES, RSN_CSE_CCMP },
1139 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
1140 		{ RSN_OUI_BYTES, RSN_CSE_NULL },
1141 	};
1142 	static const u_int8_t wep104_suite[4] =
1143 		{ RSN_OUI_BYTES, RSN_CSE_WEP104 };
1144 	static const u_int8_t key_mgt_unspec[4] =
1145 		{ RSN_OUI_BYTES, RSN_ASE_8021X_UNSPEC };
1146 	static const u_int8_t key_mgt_psk[4] =
1147 		{ RSN_OUI_BYTES, RSN_ASE_8021X_PSK };
1148 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
1149 	u_int8_t *frm = ie;
1150 	u_int8_t *selcnt;
1151 
1152 	*frm++ = IEEE80211_ELEMID_RSN;
1153 	*frm++ = 0;				/* length filled in below */
1154 	ADDSHORT(frm, RSN_VERSION);
1155 
1156 	/* XXX filter out CKIP */
1157 
1158 	/* multicast cipher */
1159 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
1160 	    rsn->rsn_mcastkeylen >= 13)
1161 		ADDSELECTOR(frm, wep104_suite);
1162 	else
1163 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
1164 
1165 	/* unicast cipher list */
1166 	selcnt = frm;
1167 	ADDSHORT(frm, 0);			/* selector count */
1168 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
1169 		selcnt[0]++;
1170 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
1171 	}
1172 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
1173 		selcnt[0]++;
1174 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
1175 	}
1176 
1177 	/* authenticator selector list */
1178 	selcnt = frm;
1179 	ADDSHORT(frm, 0);			/* selector count */
1180 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
1181 		selcnt[0]++;
1182 		ADDSELECTOR(frm, key_mgt_unspec);
1183 	}
1184 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
1185 		selcnt[0]++;
1186 		ADDSELECTOR(frm, key_mgt_psk);
1187 	}
1188 
1189 	/* optional capabilities */
1190 	ADDSHORT(frm, rsn->rsn_caps);
1191 	/* XXX PMKID */
1192 
1193 	/* calculate element length */
1194 	ie[1] = frm - ie - 2;
1195 	IASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
1196 		("RSN IE too big, %u > %zu",
1197 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
1198 	return frm;
1199 #undef ADDSELECTOR
1200 #undef ADDSHORT
1201 #undef RSN_OUI_BYTES
1202 }
1203 
1204 /*
1205  * Add a WPA/RSN element to a frame.
1206  */
1207 static u_int8_t *
1208 ieee80211_add_wpa(u_int8_t *frm, struct ieee80211com *ic)
1209 {
1210 
1211 	IASSERT(ic->ic_flags & IEEE80211_F_WPA, ("no WPA/RSN!"));
1212 	if (ic->ic_flags & IEEE80211_F_WPA2)
1213 		frm = ieee80211_setup_rsn_ie(ic, frm);
1214 	if (ic->ic_flags & IEEE80211_F_WPA1)
1215 		frm = ieee80211_setup_wpa_ie(ic, frm);
1216 	return frm;
1217 }
1218 
1219 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
1220 /*
1221  * Add a WME information element to a frame.
1222  */
1223 static u_int8_t *
1224 ieee80211_add_wme_info(u_int8_t *frm, struct ieee80211_wme_state *wme)
1225 {
1226 	static const struct ieee80211_wme_info info = {
1227 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1228 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
1229 		.wme_oui	= { WME_OUI_BYTES },
1230 		.wme_type	= WME_OUI_TYPE,
1231 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
1232 		.wme_version	= WME_VERSION,
1233 		.wme_info	= 0,
1234 	};
1235 	memcpy(frm, &info, sizeof(info));
1236 	return frm + sizeof(info);
1237 }
1238 
1239 /*
1240  * Add a WME parameters element to a frame.
1241  */
1242 static u_int8_t *
1243 ieee80211_add_wme_param(u_int8_t *frm, struct ieee80211_wme_state *wme)
1244 {
1245 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
1246 #define	ADDSHORT(frm, v) do {			\
1247 	frm[0] = (v) & 0xff;			\
1248 	frm[1] = (v) >> 8;			\
1249 	frm += 2;				\
1250 } while (0)
1251 	/* NB: this works 'cuz a param has an info at the front */
1252 	static const struct ieee80211_wme_info param = {
1253 		.wme_id		= IEEE80211_ELEMID_VENDOR,
1254 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
1255 		.wme_oui	= { WME_OUI_BYTES },
1256 		.wme_type	= WME_OUI_TYPE,
1257 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
1258 		.wme_version	= WME_VERSION,
1259 	};
1260 	int i;
1261 
1262 	memcpy(frm, &param, sizeof(param));
1263 	frm += offsetof(struct ieee80211_wme_info, wme_info);
1264 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
1265 	*frm++ = 0;					/* reserved field */
1266 	for (i = 0; i < WME_NUM_AC; i++) {
1267 		const struct wmeParams *ac =
1268 		       &wme->wme_bssChanParams.cap_wmeParams[i];
1269 		*frm++ = SM(i, WME_PARAM_ACI)
1270 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
1271 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
1272 		       ;
1273 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
1274 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
1275 		       ;
1276 		ADDSHORT(frm, ac->wmep_txopLimit);
1277 	}
1278 	return frm;
1279 #undef SM
1280 #undef ADDSHORT
1281 }
1282 #undef WME_OUI_BYTES
1283 
1284 /*
1285  * Send a probe request frame with the specified ssid
1286  * and any optional information element data.
1287  */
1288 int
1289 ieee80211_send_probereq(struct ieee80211_node *ni,
1290 	const u_int8_t sa[IEEE80211_ADDR_LEN],
1291 	const u_int8_t da[IEEE80211_ADDR_LEN],
1292 	const u_int8_t bssid[IEEE80211_ADDR_LEN],
1293 	const u_int8_t *ssid, size_t ssidlen,
1294 	const void *optie, size_t optielen)
1295 {
1296 	struct ieee80211com *ic = ni->ni_ic;
1297 	enum ieee80211_phymode mode;
1298 	struct ieee80211_frame *wh;
1299 	struct mbuf *m;
1300 	u_int8_t *frm;
1301 
1302 	/*
1303 	 * Hold a reference on the node so it doesn't go away until after
1304 	 * the xmit is complete all the way in the driver.  On error we
1305 	 * will remove our reference.
1306 	 */
1307 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1308 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1309 		__func__, __LINE__,
1310 		ni, ether_sprintf(ni->ni_macaddr),
1311 		ieee80211_node_refcnt(ni)+1);
1312 	ieee80211_ref_node(ni);
1313 
1314 	/*
1315 	 * prreq frame format
1316 	 *	[tlv] ssid
1317 	 *	[tlv] supported rates
1318 	 *	[tlv] extended supported rates
1319 	 *	[tlv] user-specified ie's
1320 	 */
1321 	m = ieee80211_getmgtframe(&frm,
1322 		 2 + IEEE80211_NWID_LEN
1323 	       + 2 + IEEE80211_RATE_SIZE
1324 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1325 	       + (optie != NULL ? optielen : 0)
1326 	);
1327 	if (m == NULL) {
1328 		ic->ic_stats.is_tx_nobuf++;
1329 		ieee80211_free_node(ni);
1330 		return ENOMEM;
1331 	}
1332 
1333 	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
1334 	mode = ieee80211_chan2mode(ic, ic->ic_curchan);
1335 	frm = ieee80211_add_rates(frm, &ic->ic_sup_rates[mode]);
1336 	frm = ieee80211_add_xrates(frm, &ic->ic_sup_rates[mode]);
1337 
1338 	if (optie != NULL) {
1339 		memcpy(frm, optie, optielen);
1340 		frm += optielen;
1341 	}
1342 	m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1343 
1344 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1345 	if (m == NULL)
1346 		return ENOMEM;
1347 	IASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
1348 	m->m_pkthdr.rcvif = (void *)ni;
1349 
1350 	wh = mtod(m, struct ieee80211_frame *);
1351 	ieee80211_send_setup(ic, ni, wh,
1352 		IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
1353 		sa, da, bssid);
1354 	/* XXX power management? */
1355 
1356 	IEEE80211_NODE_STAT(ni, tx_probereq);
1357 	IEEE80211_NODE_STAT(ni, tx_mgmt);
1358 
1359 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
1360 	    "[%s] send probe req on channel %u\n",
1361 	    ether_sprintf(wh->i_addr1),
1362 	    ieee80211_chan2ieee(ic, ic->ic_curchan));
1363 
1364 	IF_ENQUEUE(&ic->ic_mgtq, m);
1365 	(*ic->ic_ifp->if_start)(ic->ic_ifp);
1366 	return 0;
1367 }
1368 
1369 /*
1370  * Send a management frame.  The node is for the destination (or ic_bss
1371  * when in station mode).  Nodes other than ic_bss have their reference
1372  * count bumped to reflect our use for an indeterminant time.
1373  */
1374 int
1375 ieee80211_send_mgmt(struct ieee80211com *ic, struct ieee80211_node *ni,
1376 	int type, int arg)
1377 {
1378 #define	senderr(_x, _v)	do { ic->ic_stats._v++; ret = _x; goto bad; } while (0)
1379 	struct mbuf *m;
1380 	u_int8_t *frm;
1381 	u_int16_t capinfo;
1382 	int has_challenge, is_shared_key, ret, timer, status;
1383 
1384 	IASSERT(ni != NULL, ("null node"));
1385 
1386 	/*
1387 	 * Hold a reference on the node so it doesn't go away until after
1388 	 * the xmit is complete all the way in the driver.  On error we
1389 	 * will remove our reference.
1390 	 */
1391 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1392 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1393 		__func__, __LINE__,
1394 		ni, ether_sprintf(ni->ni_macaddr),
1395 		ieee80211_node_refcnt(ni)+1);
1396 	ieee80211_ref_node(ni);
1397 
1398 	timer = 0;
1399 	switch (type) {
1400 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1401 		/*
1402 		 * probe response frame format
1403 		 *	[8] time stamp
1404 		 *	[2] beacon interval
1405 		 *	[2] cabability information
1406 		 *	[tlv] ssid
1407 		 *	[tlv] supported rates
1408 		 *	[tlv] parameter set (FH/DS)
1409 		 *	[tlv] parameter set (IBSS)
1410 		 *	[tlv] extended rate phy (ERP)
1411 		 *	[tlv] extended supported rates
1412 		 *	[tlv] WPA
1413 		 *	[tlv] WME (optional)
1414 		 */
1415 		m = ieee80211_getmgtframe(&frm,
1416 			 8
1417 		       + sizeof(u_int16_t)
1418 		       + sizeof(u_int16_t)
1419 		       + 2 + IEEE80211_NWID_LEN
1420 		       + 2 + IEEE80211_RATE_SIZE
1421 		       + 7	/* max(7,3) */
1422 		       + 6
1423 		       + 3
1424 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1425 		       /* XXX !WPA1+WPA2 fits w/o a cluster */
1426 		       + (ic->ic_flags & IEEE80211_F_WPA ?
1427 				2*sizeof(struct ieee80211_ie_wpa) : 0)
1428 		       + sizeof(struct ieee80211_wme_param)
1429 		);
1430 		if (m == NULL)
1431 			senderr(ENOMEM, is_tx_nobuf);
1432 
1433 		memset(frm, 0, 8);	/* timestamp should be filled later */
1434 		frm += 8;
1435 		*(u_int16_t *)frm = htole16(ic->ic_bss->ni_intval);
1436 		frm += 2;
1437 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1438 			capinfo = IEEE80211_CAPINFO_IBSS;
1439 		else
1440 			capinfo = IEEE80211_CAPINFO_ESS;
1441 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1442 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1443 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1444 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1445 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1446 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1447 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1448 		*(u_int16_t *)frm = htole16(capinfo);
1449 		frm += 2;
1450 
1451 		frm = ieee80211_add_ssid(frm, ic->ic_bss->ni_essid,
1452 				ic->ic_bss->ni_esslen);
1453 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1454 
1455 		if (ic->ic_phytype == IEEE80211_T_FH) {
1456                         *frm++ = IEEE80211_ELEMID_FHPARMS;
1457                         *frm++ = 5;
1458                         *frm++ = ni->ni_fhdwell & 0x00ff;
1459                         *frm++ = (ni->ni_fhdwell >> 8) & 0x00ff;
1460                         *frm++ = IEEE80211_FH_CHANSET(
1461 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1462                         *frm++ = IEEE80211_FH_CHANPAT(
1463 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1464                         *frm++ = ni->ni_fhindex;
1465 		} else {
1466 			*frm++ = IEEE80211_ELEMID_DSPARMS;
1467 			*frm++ = 1;
1468 			*frm++ = ieee80211_chan2ieee(ic, ic->ic_curchan);
1469 		}
1470 
1471 		if (ic->ic_opmode == IEEE80211_M_IBSS) {
1472 			*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1473 			*frm++ = 2;
1474 			*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1475 		}
1476 		if (ic->ic_flags & IEEE80211_F_WPA)
1477 			frm = ieee80211_add_wpa(frm, ic);
1478 		if (ic->ic_curmode == IEEE80211_MODE_11G)
1479 			frm = ieee80211_add_erp(frm, ic);
1480 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1481 		if (ic->ic_flags & IEEE80211_F_WME)
1482 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1483 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1484 		break;
1485 
1486 	case IEEE80211_FC0_SUBTYPE_AUTH:
1487 		status = arg >> 16;
1488 		arg &= 0xffff;
1489 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1490 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1491 		    ni->ni_challenge != NULL);
1492 
1493 		/*
1494 		 * Deduce whether we're doing open authentication or
1495 		 * shared key authentication.  We do the latter if
1496 		 * we're in the middle of a shared key authentication
1497 		 * handshake or if we're initiating an authentication
1498 		 * request and configured to use shared key.
1499 		 */
1500 		is_shared_key = has_challenge ||
1501 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1502 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1503 		      ic->ic_bss->ni_authmode == IEEE80211_AUTH_SHARED);
1504 
1505 		m = ieee80211_getmgtframe(&frm,
1506 			  3 * sizeof(u_int16_t)
1507 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1508 				sizeof(u_int16_t)+IEEE80211_CHALLENGE_LEN : 0)
1509 		);
1510 		if (m == NULL)
1511 			senderr(ENOMEM, is_tx_nobuf);
1512 
1513 		((u_int16_t *)frm)[0] =
1514 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1515 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1516 		((u_int16_t *)frm)[1] = htole16(arg);	/* sequence number */
1517 		((u_int16_t *)frm)[2] = htole16(status);/* status */
1518 
1519 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1520 			((u_int16_t *)frm)[3] =
1521 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1522 			    IEEE80211_ELEMID_CHALLENGE);
1523 			memcpy(&((u_int16_t *)frm)[4], ni->ni_challenge,
1524 			    IEEE80211_CHALLENGE_LEN);
1525 			m->m_pkthdr.len = m->m_len =
1526 				4 * sizeof(u_int16_t) + IEEE80211_CHALLENGE_LEN;
1527 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1528 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1529 				    "[%s] request encrypt frame (%s)\n",
1530 				    ether_sprintf(ni->ni_macaddr), __func__);
1531 				m->m_flags |= M_LINK0; /* WEP-encrypt, please */
1532 			}
1533 		} else
1534 			m->m_pkthdr.len = m->m_len = 3 * sizeof(u_int16_t);
1535 
1536 		/* XXX not right for shared key */
1537 		if (status == IEEE80211_STATUS_SUCCESS)
1538 			IEEE80211_NODE_STAT(ni, tx_auth);
1539 		else
1540 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1541 
1542 		if (ic->ic_opmode == IEEE80211_M_STA)
1543 			timer = IEEE80211_TRANS_WAIT;
1544 		break;
1545 
1546 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1547 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1548 			"[%s] send station deauthenticate (reason %d)\n",
1549 			ether_sprintf(ni->ni_macaddr), arg);
1550 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1551 		if (m == NULL)
1552 			senderr(ENOMEM, is_tx_nobuf);
1553 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1554 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1555 
1556 		IEEE80211_NODE_STAT(ni, tx_deauth);
1557 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1558 
1559 		ieee80211_node_unauthorize(ni);		/* port closed */
1560 		break;
1561 
1562 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1563 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1564 		/*
1565 		 * asreq frame format
1566 		 *	[2] capability information
1567 		 *	[2] listen interval
1568 		 *	[6*] current AP address (reassoc only)
1569 		 *	[tlv] ssid
1570 		 *	[tlv] supported rates
1571 		 *	[tlv] extended supported rates
1572 		 *	[tlv] WME
1573 		 *	[tlv] user-specified ie's
1574 		 */
1575 		m = ieee80211_getmgtframe(&frm,
1576 			 sizeof(u_int16_t)
1577 		       + sizeof(u_int16_t)
1578 		       + IEEE80211_ADDR_LEN
1579 		       + 2 + IEEE80211_NWID_LEN
1580 		       + 2 + IEEE80211_RATE_SIZE
1581 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1582 		       + sizeof(struct ieee80211_wme_info)
1583 		       + (ic->ic_opt_ie != NULL ? ic->ic_opt_ie_len : 0)
1584 		);
1585 		if (m == NULL)
1586 			senderr(ENOMEM, is_tx_nobuf);
1587 
1588 		capinfo = 0;
1589 		if (ic->ic_opmode == IEEE80211_M_IBSS)
1590 			capinfo |= IEEE80211_CAPINFO_IBSS;
1591 		else		/* IEEE80211_M_STA */
1592 			capinfo |= IEEE80211_CAPINFO_ESS;
1593 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1594 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1595 		/*
1596 		 * NB: Some 11a AP's reject the request when
1597 		 *     short premable is set.
1598 		 */
1599 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1600 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1601 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1602 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) &&
1603 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
1604 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1605 		*(u_int16_t *)frm = htole16(capinfo);
1606 		frm += 2;
1607 
1608 		*(u_int16_t *)frm = htole16(ic->ic_lintval);
1609 		frm += 2;
1610 
1611 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
1612 			IEEE80211_ADDR_COPY(frm, ic->ic_bss->ni_bssid);
1613 			frm += IEEE80211_ADDR_LEN;
1614 		}
1615 
1616 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
1617 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1618 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1619 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1620 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
1621 		if (ic->ic_opt_ie != NULL) {
1622 			memcpy(frm, ic->ic_opt_ie, ic->ic_opt_ie_len);
1623 			frm += ic->ic_opt_ie_len;
1624 		}
1625 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1626 
1627 		timer = IEEE80211_TRANS_WAIT;
1628 		break;
1629 
1630 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1631 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1632 		/*
1633 		 * asreq frame format
1634 		 *	[2] capability information
1635 		 *	[2] status
1636 		 *	[2] association ID
1637 		 *	[tlv] supported rates
1638 		 *	[tlv] extended supported rates
1639 		 *	[tlv] WME (if enabled and STA enabled)
1640 		 */
1641 		m = ieee80211_getmgtframe(&frm,
1642 			 sizeof(u_int16_t)
1643 		       + sizeof(u_int16_t)
1644 		       + sizeof(u_int16_t)
1645 		       + 2 + IEEE80211_RATE_SIZE
1646 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1647 		       + sizeof(struct ieee80211_wme_param)
1648 		);
1649 		if (m == NULL)
1650 			senderr(ENOMEM, is_tx_nobuf);
1651 
1652 		capinfo = IEEE80211_CAPINFO_ESS;
1653 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1654 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1655 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1656 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1657 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1658 		if (ic->ic_flags & IEEE80211_F_SHSLOT)
1659 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1660 		*(u_int16_t *)frm = htole16(capinfo);
1661 		frm += 2;
1662 
1663 		*(u_int16_t *)frm = htole16(arg);	/* status */
1664 		frm += 2;
1665 
1666 		if (arg == IEEE80211_STATUS_SUCCESS) {
1667 			*(u_int16_t *)frm = htole16(ni->ni_associd);
1668 			IEEE80211_NODE_STAT(ni, tx_assoc);
1669 		} else
1670 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
1671 		frm += 2;
1672 
1673 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1674 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1675 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1676 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1677 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1678 		break;
1679 
1680 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
1681 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1682 			"[%s] send station disassociate (reason %d)\n",
1683 			ether_sprintf(ni->ni_macaddr), arg);
1684 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1685 		if (m == NULL)
1686 			senderr(ENOMEM, is_tx_nobuf);
1687 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1688 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1689 
1690 		IEEE80211_NODE_STAT(ni, tx_disassoc);
1691 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
1692 		break;
1693 
1694 	default:
1695 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1696 			"[%s] invalid mgmt frame type %u\n",
1697 			ether_sprintf(ni->ni_macaddr), type);
1698 		senderr(EINVAL, is_tx_unknownmgt);
1699 		/* NOTREACHED */
1700 	}
1701 	ret = ieee80211_mgmt_output(ic, ni, m, type, timer);
1702 	if (ret != 0) {
1703 bad:
1704 		ieee80211_free_node(ni);
1705 	}
1706 	return ret;
1707 #undef senderr
1708 }
1709 
1710 /*
1711  * Build a RTS (Request To Send) control frame.
1712  */
1713 struct mbuf *
1714 ieee80211_get_rts(struct ieee80211com *ic, const struct ieee80211_frame *wh,
1715     uint16_t dur)
1716 {
1717 	struct ieee80211_frame_rts *rts;
1718 	struct mbuf *m;
1719 
1720 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1721 	if (m == NULL)
1722 		return NULL;
1723 
1724 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_rts);
1725 
1726 	rts = mtod(m, struct ieee80211_frame_rts *);
1727 	rts->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_CTL |
1728 	    IEEE80211_FC0_SUBTYPE_RTS;
1729 	rts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1730 	*(uint16_t *)rts->i_dur = htole16(dur);
1731 	IEEE80211_ADDR_COPY(rts->i_ra, wh->i_addr1);
1732 	IEEE80211_ADDR_COPY(rts->i_ta, wh->i_addr2);
1733 
1734 	return m;
1735 }
1736 
1737 /*
1738  * Build a CTS-to-self (Clear To Send) control frame.
1739  */
1740 struct mbuf *
1741 ieee80211_get_cts_to_self(struct ieee80211com *ic, uint16_t dur)
1742 {
1743 	struct ieee80211_frame_cts *cts;
1744 	struct mbuf *m;
1745 
1746 	MGETHDR(m, M_DONTWAIT, MT_DATA);
1747 	if (m == NULL)
1748 		return NULL;
1749 
1750 	m->m_pkthdr.len = m->m_len = sizeof(struct ieee80211_frame_cts);
1751 
1752 	cts = mtod(m, struct ieee80211_frame_cts *);
1753 	cts->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_CTL |
1754 	    IEEE80211_FC0_SUBTYPE_CTS;
1755 	cts->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1756 	*(uint16_t *)cts->i_dur = htole16(dur);
1757 	IEEE80211_ADDR_COPY(cts->i_ra, ic->ic_myaddr);
1758 
1759 	return m;
1760 }
1761 
1762 /*
1763  * Allocate a beacon frame and fillin the appropriate bits.
1764  */
1765 struct mbuf *
1766 ieee80211_beacon_alloc(struct ieee80211com *ic, struct ieee80211_node *ni,
1767 	struct ieee80211_beacon_offsets *bo)
1768 {
1769 	struct ifnet *ifp = ic->ic_ifp;
1770 	struct ieee80211_frame *wh;
1771 	struct mbuf *m;
1772 	int pktlen;
1773 	u_int8_t *frm, *efrm;
1774 	u_int16_t capinfo;
1775 	struct ieee80211_rateset *rs;
1776 
1777 	/*
1778 	 * beacon frame format
1779 	 *	[8] time stamp
1780 	 *	[2] beacon interval
1781 	 *	[2] cabability information
1782 	 *	[tlv] ssid
1783 	 *	[tlv] supported rates
1784 	 *	[3] parameter set (DS)
1785 	 *	[tlv] parameter set (IBSS/TIM)
1786 	 *	[tlv] extended rate phy (ERP)
1787 	 *	[tlv] extended supported rates
1788 	 *	[tlv] WME parameters
1789 	 *	[tlv] WPA/RSN parameters
1790 	 * XXX Vendor-specific OIDs (e.g. Atheros)
1791 	 * NB: we allocate the max space required for the TIM bitmap.
1792 	 */
1793 	rs = &ni->ni_rates;
1794 	pktlen =   8					/* time stamp */
1795 		 + sizeof(u_int16_t)			/* beacon interval */
1796 		 + sizeof(u_int16_t)			/* capabilities */
1797 		 + 2 + ni->ni_esslen			/* ssid */
1798 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
1799 	         + 2 + 1				/* DS parameters */
1800 		 + 2 + 4 + ic->ic_tim_len		/* DTIM/IBSSPARMS */
1801 		 + 2 + 1				/* ERP */
1802 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1803 		 + (ic->ic_caps & IEEE80211_C_WME ?	/* WME */
1804 			sizeof(struct ieee80211_wme_param) : 0)
1805 		 + (ic->ic_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
1806 			2*sizeof(struct ieee80211_ie_wpa) : 0)
1807 		 ;
1808 	m = ieee80211_getmgtframe(&frm, pktlen);
1809 	if (m == NULL) {
1810 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1811 			"%s: cannot get buf; size %u\n", __func__, pktlen);
1812 		ic->ic_stats.is_tx_nobuf++;
1813 		return NULL;
1814 	}
1815 
1816 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
1817 	frm += 8;
1818 	*(u_int16_t *)frm = htole16(ni->ni_intval);
1819 	frm += 2;
1820 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1821 		capinfo = IEEE80211_CAPINFO_IBSS;
1822 	else
1823 		capinfo = IEEE80211_CAPINFO_ESS;
1824 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1825 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1826 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1827 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1828 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1829 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1830 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1831 	bo->bo_caps = (u_int16_t *)frm;
1832 	*(u_int16_t *)frm = htole16(capinfo);
1833 	frm += 2;
1834 	*frm++ = IEEE80211_ELEMID_SSID;
1835 	if ((ic->ic_flags & IEEE80211_F_HIDESSID) == 0) {
1836 		*frm++ = ni->ni_esslen;
1837 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
1838 		frm += ni->ni_esslen;
1839 	} else
1840 		*frm++ = 0;
1841 	frm = ieee80211_add_rates(frm, rs);
1842 	if (ic->ic_curmode != IEEE80211_MODE_FH) {
1843 		*frm++ = IEEE80211_ELEMID_DSPARMS;
1844 		*frm++ = 1;
1845 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
1846 	}
1847 	bo->bo_tim = frm;
1848 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
1849 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1850 		*frm++ = 2;
1851 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1852 		bo->bo_tim_len = 0;
1853 	} else {
1854 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
1855 
1856 		tie->tim_ie = IEEE80211_ELEMID_TIM;
1857 		tie->tim_len = 4;	/* length */
1858 		tie->tim_count = 0;	/* DTIM count */
1859 		tie->tim_period = ic->ic_dtim_period;	/* DTIM period */
1860 		tie->tim_bitctl = 0;	/* bitmap control */
1861 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
1862 		frm += sizeof(struct ieee80211_tim_ie);
1863 		bo->bo_tim_len = 1;
1864 	}
1865 	bo->bo_trailer = frm;
1866 	if (ic->ic_flags & IEEE80211_F_WME) {
1867 		bo->bo_wme = frm;
1868 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1869 		ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1870 	}
1871 	if (ic->ic_flags & IEEE80211_F_WPA)
1872 		frm = ieee80211_add_wpa(frm, ic);
1873 	if (ic->ic_curmode == IEEE80211_MODE_11G)
1874 		frm = ieee80211_add_erp(frm, ic);
1875 	efrm = ieee80211_add_xrates(frm, rs);
1876 	bo->bo_trailer_len = efrm - bo->bo_trailer;
1877 	m->m_pkthdr.len = m->m_len = efrm - mtod(m, u_int8_t *);
1878 
1879 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1880 	IASSERT(m != NULL, ("no space for 802.11 header?"));
1881 	wh = mtod(m, struct ieee80211_frame *);
1882 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
1883 	    IEEE80211_FC0_SUBTYPE_BEACON;
1884 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1885 	*(u_int16_t *)wh->i_dur = 0;
1886 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
1887 	IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
1888 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
1889 	*(u_int16_t *)wh->i_seq = 0;
1890 
1891 	return m;
1892 }
1893 
1894 /*
1895  * Update the dynamic parts of a beacon frame based on the current state.
1896  */
1897 int
1898 ieee80211_beacon_update(struct ieee80211com *ic, struct ieee80211_node *ni,
1899     struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
1900 {
1901 	int len_changed = 0;
1902 	u_int16_t capinfo;
1903 
1904 	IEEE80211_BEACON_LOCK(ic);
1905 	/* XXX faster to recalculate entirely or just changes? */
1906 	if (ic->ic_opmode == IEEE80211_M_IBSS)
1907 		capinfo = IEEE80211_CAPINFO_IBSS;
1908 	else
1909 		capinfo = IEEE80211_CAPINFO_ESS;
1910 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1911 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1912 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1913 	    IEEE80211_IS_CHAN_2GHZ(ni->ni_chan))
1914 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1915 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1916 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1917 	*bo->bo_caps = htole16(capinfo);
1918 
1919 	if (ic->ic_flags & IEEE80211_F_WME) {
1920 		struct ieee80211_wme_state *wme = &ic->ic_wme;
1921 
1922 		/*
1923 		 * Check for agressive mode change.  When there is
1924 		 * significant high priority traffic in the BSS
1925 		 * throttle back BE traffic by using conservative
1926 		 * parameters.  Otherwise BE uses agressive params
1927 		 * to optimize performance of legacy/non-QoS traffic.
1928 		 */
1929 		if (wme->wme_flags & WME_F_AGGRMODE) {
1930 			if (wme->wme_hipri_traffic >
1931 			    wme->wme_hipri_switch_thresh) {
1932 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1933 				    "%s: traffic %u, disable aggressive mode\n",
1934 				    __func__, wme->wme_hipri_traffic);
1935 				wme->wme_flags &= ~WME_F_AGGRMODE;
1936 				ieee80211_wme_updateparams_locked(ic);
1937 				wme->wme_hipri_traffic =
1938 					wme->wme_hipri_switch_hysteresis;
1939 			} else
1940 				wme->wme_hipri_traffic = 0;
1941 		} else {
1942 			if (wme->wme_hipri_traffic <=
1943 			    wme->wme_hipri_switch_thresh) {
1944 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1945 				    "%s: traffic %u, enable aggressive mode\n",
1946 				    __func__, wme->wme_hipri_traffic);
1947 				wme->wme_flags |= WME_F_AGGRMODE;
1948 				ieee80211_wme_updateparams_locked(ic);
1949 				wme->wme_hipri_traffic = 0;
1950 			} else
1951 				wme->wme_hipri_traffic =
1952 					wme->wme_hipri_switch_hysteresis;
1953 		}
1954 		if (ic->ic_flags & IEEE80211_F_WMEUPDATE) {
1955 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
1956 			ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1957 		}
1958 	}
1959 
1960 #ifndef IEEE80211_NO_HOSTAP
1961 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {	/* NB: no IBSS support*/
1962 		struct ieee80211_tim_ie *tie =
1963 			(struct ieee80211_tim_ie *) bo->bo_tim;
1964 		if (ic->ic_flags & IEEE80211_F_TIMUPDATE) {
1965 			u_int timlen, timoff, i;
1966 			/*
1967 			 * ATIM/DTIM needs updating.  If it fits in the
1968 			 * current space allocated then just copy in the
1969 			 * new bits.  Otherwise we need to move any trailing
1970 			 * data to make room.  Note that we know there is
1971 			 * contiguous space because ieee80211_beacon_allocate
1972 			 * insures there is space in the mbuf to write a
1973 			 * maximal-size virtual bitmap (based on ic_max_aid).
1974 			 */
1975 			/*
1976 			 * Calculate the bitmap size and offset, copy any
1977 			 * trailer out of the way, and then copy in the
1978 			 * new bitmap and update the information element.
1979 			 * Note that the tim bitmap must contain at least
1980 			 * one byte and any offset must be even.
1981 			 */
1982 			if (ic->ic_ps_pending != 0) {
1983 				timoff = 128;		/* impossibly large */
1984 				for (i = 0; i < ic->ic_tim_len; i++)
1985 					if (ic->ic_tim_bitmap[i]) {
1986 						timoff = i &~ 1;
1987 						break;
1988 					}
1989 				IASSERT(timoff != 128, ("tim bitmap empty!"));
1990 				for (i = ic->ic_tim_len-1; i >= timoff; i--)
1991 					if (ic->ic_tim_bitmap[i])
1992 						break;
1993 				timlen = 1 + (i - timoff);
1994 			} else {
1995 				timoff = 0;
1996 				timlen = 1;
1997 			}
1998 			if (timlen != bo->bo_tim_len) {
1999 				/* copy up/down trailer */
2000 				ovbcopy(bo->bo_trailer, tie->tim_bitmap+timlen,
2001 					bo->bo_trailer_len);
2002 				bo->bo_trailer = tie->tim_bitmap+timlen;
2003 				bo->bo_wme = bo->bo_trailer;
2004 				bo->bo_tim_len = timlen;
2005 
2006 				/* update information element */
2007 				tie->tim_len = 3 + timlen;
2008 				tie->tim_bitctl = timoff;
2009 				len_changed = 1;
2010 			}
2011 			memcpy(tie->tim_bitmap, ic->ic_tim_bitmap + timoff,
2012 				bo->bo_tim_len);
2013 
2014 			ic->ic_flags &= ~IEEE80211_F_TIMUPDATE;
2015 
2016 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
2017 				"%s: TIM updated, pending %u, off %u, len %u\n",
2018 				__func__, ic->ic_ps_pending, timoff, timlen);
2019 		}
2020 		/* count down DTIM period */
2021 		if (tie->tim_count == 0)
2022 			tie->tim_count = tie->tim_period - 1;
2023 		else
2024 			tie->tim_count--;
2025 		/* update state for buffered multicast frames on DTIM */
2026 		if (mcast && (tie->tim_count == 1 || tie->tim_period == 1))
2027 			tie->tim_bitctl |= 1;
2028 		else
2029 			tie->tim_bitctl &= ~1;
2030 	}
2031 #endif /* !IEEE80211_NO_HOSTAP */
2032 	IEEE80211_BEACON_UNLOCK(ic);
2033 
2034 	return len_changed;
2035 }
2036 
2037 /*
2038  * Save an outbound packet for a node in power-save sleep state.
2039  * The new packet is placed on the node's saved queue, and the TIM
2040  * is changed, if necessary.
2041  */
2042 void
2043 ieee80211_pwrsave(struct ieee80211com *ic, struct ieee80211_node *ni,
2044 		  struct mbuf *m)
2045 {
2046 	int qlen, age;
2047 
2048 	IEEE80211_NODE_SAVEQ_LOCK(ni);
2049 	if (IF_QFULL(&ni->ni_savedq)) {
2050 		IF_DROP(&ni->ni_savedq);
2051 		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
2052 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
2053 			"[%s] pwr save q overflow, drops %d (size %d)\n",
2054 			ether_sprintf(ni->ni_macaddr),
2055 			ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE);
2056 #ifdef IEEE80211_DEBUG
2057 		if (ieee80211_msg_dumppkts(ic))
2058 			ieee80211_dump_pkt(mtod(m, void *), m->m_len, -1, -1);
2059 #endif
2060 		m_freem(m);
2061 		return;
2062 	}
2063 	/*
2064 	 * Tag the frame with its expiry time and insert
2065 	 * it in the queue.  The aging interval is 4 times
2066 	 * the listen interval specified by the station.
2067 	 * Frames that sit around too long are reclaimed
2068 	 * using this information.
2069 	 */
2070 	/* XXX handle overflow? */
2071 	age = ((ni->ni_intval * ic->ic_bintval) << 2) / 1024; /* TU -> secs */
2072 	_IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age);
2073 	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
2074 
2075 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
2076 		"[%s] save frame with age %d, %u now queued\n",
2077 		ether_sprintf(ni->ni_macaddr), age, qlen);
2078 
2079 	if (qlen == 1)
2080 		ic->ic_set_tim(ni, 1);
2081 }
2082