xref: /freebsd/sys/net80211/ieee80211_output.c (revision d056fa046c6a91b90cd98165face0e42a33a5173)
1 /*-
2  * Copyright (c) 2001 Atsushi Onoe
3  * Copyright (c) 2002-2005 Sam Leffler, Errno Consulting
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission.
16  *
17  * Alternatively, this software may be distributed under the terms of the
18  * GNU General Public License ("GPL") version 2 as published by the Free
19  * Software Foundation.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include "opt_inet.h"
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/mbuf.h>
41 #include <sys/kernel.h>
42 #include <sys/endian.h>
43 
44 #include <sys/socket.h>
45 
46 #include <net/bpf.h>
47 #include <net/ethernet.h>
48 #include <net/if.h>
49 #include <net/if_llc.h>
50 #include <net/if_media.h>
51 #include <net/if_vlan_var.h>
52 
53 #include <net80211/ieee80211_var.h>
54 
55 #ifdef INET
56 #include <netinet/in.h>
57 #include <netinet/if_ether.h>
58 #include <netinet/in_systm.h>
59 #include <netinet/ip.h>
60 #endif
61 
62 #ifdef IEEE80211_DEBUG
63 /*
64  * Decide if an outbound management frame should be
65  * printed when debugging is enabled.  This filters some
66  * of the less interesting frames that come frequently
67  * (e.g. beacons).
68  */
69 static __inline int
70 doprint(struct ieee80211com *ic, int subtype)
71 {
72 	switch (subtype) {
73 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
74 		return (ic->ic_opmode == IEEE80211_M_IBSS);
75 	}
76 	return 1;
77 }
78 #endif
79 
80 /*
81  * Set the direction field and address fields of an outgoing
82  * non-QoS frame.  Note this should be called early on in
83  * constructing a frame as it sets i_fc[1]; other bits can
84  * then be or'd in.
85  */
86 static void
87 ieee80211_send_setup(struct ieee80211com *ic,
88 	struct ieee80211_node *ni,
89 	struct ieee80211_frame *wh,
90 	int type,
91 	const u_int8_t sa[IEEE80211_ADDR_LEN],
92 	const u_int8_t da[IEEE80211_ADDR_LEN],
93 	const u_int8_t bssid[IEEE80211_ADDR_LEN])
94 {
95 #define	WH4(wh)	((struct ieee80211_frame_addr4 *)wh)
96 
97 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | type;
98 	if ((type & IEEE80211_FC0_TYPE_MASK) == IEEE80211_FC0_TYPE_DATA) {
99 		switch (ic->ic_opmode) {
100 		case IEEE80211_M_STA:
101 			wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
102 			IEEE80211_ADDR_COPY(wh->i_addr1, bssid);
103 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
104 			IEEE80211_ADDR_COPY(wh->i_addr3, da);
105 			break;
106 		case IEEE80211_M_IBSS:
107 		case IEEE80211_M_AHDEMO:
108 			wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
109 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
110 			IEEE80211_ADDR_COPY(wh->i_addr2, sa);
111 			IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
112 			break;
113 		case IEEE80211_M_HOSTAP:
114 			wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
115 			IEEE80211_ADDR_COPY(wh->i_addr1, da);
116 			IEEE80211_ADDR_COPY(wh->i_addr2, bssid);
117 			IEEE80211_ADDR_COPY(wh->i_addr3, sa);
118 			break;
119 		case IEEE80211_M_MONITOR:	/* NB: to quiet compiler */
120 			break;
121 		}
122 	} else {
123 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
124 		IEEE80211_ADDR_COPY(wh->i_addr1, da);
125 		IEEE80211_ADDR_COPY(wh->i_addr2, sa);
126 		IEEE80211_ADDR_COPY(wh->i_addr3, bssid);
127 	}
128 	*(u_int16_t *)&wh->i_dur[0] = 0;
129 	/* NB: use non-QoS tid */
130 	*(u_int16_t *)&wh->i_seq[0] =
131 	    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
132 	ni->ni_txseqs[0]++;
133 #undef WH4
134 }
135 
136 /*
137  * Send a management frame to the specified node.  The node pointer
138  * must have a reference as the pointer will be passed to the driver
139  * and potentially held for a long time.  If the frame is successfully
140  * dispatched to the driver, then it is responsible for freeing the
141  * reference (and potentially free'ing up any associated storage).
142  */
143 static int
144 ieee80211_mgmt_output(struct ieee80211com *ic, struct ieee80211_node *ni,
145     struct mbuf *m, int type, int timer)
146 {
147 	struct ifnet *ifp = ic->ic_ifp;
148 	struct ieee80211_frame *wh;
149 
150 	KASSERT(ni != NULL, ("null node"));
151 
152 	/*
153 	 * Yech, hack alert!  We want to pass the node down to the
154 	 * driver's start routine.  If we don't do so then the start
155 	 * routine must immediately look it up again and that can
156 	 * cause a lock order reversal if, for example, this frame
157 	 * is being sent because the station is being timedout and
158 	 * the frame being sent is a DEAUTH message.  We could stick
159 	 * this in an m_tag and tack that on to the mbuf.  However
160 	 * that's rather expensive to do for every frame so instead
161 	 * we stuff it in the rcvif field since outbound frames do
162 	 * not (presently) use this.
163 	 */
164 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
165 	if (m == NULL)
166 		return ENOMEM;
167 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
168 	m->m_pkthdr.rcvif = (void *)ni;
169 
170 	wh = mtod(m, struct ieee80211_frame *);
171 	ieee80211_send_setup(ic, ni, wh,
172 		IEEE80211_FC0_TYPE_MGT | type,
173 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
174 	if ((m->m_flags & M_LINK0) != 0 && ni->ni_challenge != NULL) {
175 		m->m_flags &= ~M_LINK0;
176 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
177 			"[%s] encrypting frame (%s)\n",
178 			ether_sprintf(wh->i_addr1), __func__);
179 		wh->i_fc[1] |= IEEE80211_FC1_WEP;
180 	}
181 #ifdef IEEE80211_DEBUG
182 	/* avoid printing too many frames */
183 	if ((ieee80211_msg_debug(ic) && doprint(ic, type)) ||
184 	    ieee80211_msg_dumppkts(ic)) {
185 		printf("[%s] send %s on channel %u\n",
186 		    ether_sprintf(wh->i_addr1),
187 		    ieee80211_mgt_subtype_name[
188 			(type & IEEE80211_FC0_SUBTYPE_MASK) >>
189 				IEEE80211_FC0_SUBTYPE_SHIFT],
190 		    ieee80211_chan2ieee(ic, ic->ic_curchan));
191 	}
192 #endif
193 	IEEE80211_NODE_STAT(ni, tx_mgmt);
194 	IF_ENQUEUE(&ic->ic_mgtq, m);
195 	if (timer) {
196 		/*
197 		 * Set the mgt frame timeout.
198 		 */
199 		ic->ic_mgt_timer = timer;
200 		ifp->if_timer = 1;
201 	}
202 	if_start(ifp);
203 	return 0;
204 }
205 
206 /*
207  * Send a null data frame to the specified node.
208  *
209  * NB: the caller is assumed to have setup a node reference
210  *     for use; this is necessary to deal with a race condition
211  *     when probing for inactive stations.
212  */
213 int
214 ieee80211_send_nulldata(struct ieee80211_node *ni)
215 {
216 	struct ieee80211com *ic = ni->ni_ic;
217 	struct ifnet *ifp = ic->ic_ifp;
218 	struct mbuf *m;
219 	struct ieee80211_frame *wh;
220 
221 	MGETHDR(m, M_NOWAIT, MT_DATA);
222 	if (m == NULL) {
223 		/* XXX debug msg */
224 		ic->ic_stats.is_tx_nobuf++;
225 		ieee80211_unref_node(&ni);
226 		return ENOMEM;
227 	}
228 	m->m_pkthdr.rcvif = (void *) ni;
229 
230 	wh = mtod(m, struct ieee80211_frame *);
231 	ieee80211_send_setup(ic, ni, wh,
232 		IEEE80211_FC0_TYPE_DATA | IEEE80211_FC0_SUBTYPE_NODATA,
233 		ic->ic_myaddr, ni->ni_macaddr, ni->ni_bssid);
234 	/* NB: power management bit is never sent by an AP */
235 	if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) &&
236 	    ic->ic_opmode != IEEE80211_M_HOSTAP)
237 		wh->i_fc[1] |= IEEE80211_FC1_PWR_MGT;
238 	m->m_len = m->m_pkthdr.len = sizeof(struct ieee80211_frame);
239 
240 	IEEE80211_NODE_STAT(ni, tx_data);
241 
242 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
243 	    "[%s] send null data frame on channel %u, pwr mgt %s\n",
244 	    ether_sprintf(ni->ni_macaddr),
245 	    ieee80211_chan2ieee(ic, ic->ic_curchan),
246 	    wh->i_fc[1] & IEEE80211_FC1_PWR_MGT ? "ena" : "dis");
247 
248 	IF_ENQUEUE(&ic->ic_mgtq, m);		/* cheat */
249 	if_start(ifp);
250 
251 	return 0;
252 }
253 
254 /*
255  * Assign priority to a frame based on any vlan tag assigned
256  * to the station and/or any Diffserv setting in an IP header.
257  * Finally, if an ACM policy is setup (in station mode) it's
258  * applied.
259  */
260 int
261 ieee80211_classify(struct ieee80211com *ic, struct mbuf *m, struct ieee80211_node *ni)
262 {
263 	int v_wme_ac, d_wme_ac, ac;
264 #ifdef INET
265 	struct ether_header *eh;
266 #endif
267 
268 	if ((ni->ni_flags & IEEE80211_NODE_QOS) == 0) {
269 		ac = WME_AC_BE;
270 		goto done;
271 	}
272 
273 	/*
274 	 * If node has a vlan tag then all traffic
275 	 * to it must have a matching tag.
276 	 */
277 	v_wme_ac = 0;
278 	if (ni->ni_vlan != 0) {
279 		 struct m_tag *mtag = VLAN_OUTPUT_TAG(ic->ic_ifp, m);
280 		 if (mtag == NULL) {
281 			IEEE80211_NODE_STAT(ni, tx_novlantag);
282 			return 1;
283 		}
284 		if (EVL_VLANOFTAG(VLAN_TAG_VALUE(mtag)) !=
285 		    EVL_VLANOFTAG(ni->ni_vlan)) {
286 			IEEE80211_NODE_STAT(ni, tx_vlanmismatch);
287 			return 1;
288 		}
289 		/* map vlan priority to AC */
290 		switch (EVL_PRIOFTAG(ni->ni_vlan)) {
291 		case 1:
292 		case 2:
293 			v_wme_ac = WME_AC_BK;
294 			break;
295 		case 0:
296 		case 3:
297 			v_wme_ac = WME_AC_BE;
298 			break;
299 		case 4:
300 		case 5:
301 			v_wme_ac = WME_AC_VI;
302 			break;
303 		case 6:
304 		case 7:
305 			v_wme_ac = WME_AC_VO;
306 			break;
307 		}
308 	}
309 
310 #ifdef INET
311 	eh = mtod(m, struct ether_header *);
312 	if (eh->ether_type == htons(ETHERTYPE_IP)) {
313 		const struct ip *ip = (struct ip *)
314 			(mtod(m, u_int8_t *) + sizeof (*eh));
315 		/*
316 		 * IP frame, map the TOS field.
317 		 */
318 		switch (ip->ip_tos) {
319 		case 0x08:
320 		case 0x20:
321 			d_wme_ac = WME_AC_BK;	/* background */
322 			break;
323 		case 0x28:
324 		case 0xa0:
325 			d_wme_ac = WME_AC_VI;	/* video */
326 			break;
327 		case 0x30:			/* voice */
328 		case 0xe0:
329 		case 0x88:			/* XXX UPSD */
330 		case 0xb8:
331 			d_wme_ac = WME_AC_VO;
332 			break;
333 		default:
334 			d_wme_ac = WME_AC_BE;
335 			break;
336 		}
337 	} else {
338 #endif /* INET */
339 		d_wme_ac = WME_AC_BE;
340 #ifdef INET
341 	}
342 #endif
343 	/*
344 	 * Use highest priority AC.
345 	 */
346 	if (v_wme_ac > d_wme_ac)
347 		ac = v_wme_ac;
348 	else
349 		ac = d_wme_ac;
350 
351 	/*
352 	 * Apply ACM policy.
353 	 */
354 	if (ic->ic_opmode == IEEE80211_M_STA) {
355 		static const int acmap[4] = {
356 			WME_AC_BK,	/* WME_AC_BE */
357 			WME_AC_BK,	/* WME_AC_BK */
358 			WME_AC_BE,	/* WME_AC_VI */
359 			WME_AC_VI,	/* WME_AC_VO */
360 		};
361 		while (ac != WME_AC_BK &&
362 		    ic->ic_wme.wme_wmeBssChanParams.cap_wmeParams[ac].wmep_acm)
363 			ac = acmap[ac];
364 	}
365 done:
366 	M_WME_SETAC(m, ac);
367 	return 0;
368 }
369 
370 /*
371  * Insure there is sufficient contiguous space to encapsulate the
372  * 802.11 data frame.  If room isn't already there, arrange for it.
373  * Drivers and cipher modules assume we have done the necessary work
374  * and fail rudely if they don't find the space they need.
375  */
376 static struct mbuf *
377 ieee80211_mbuf_adjust(struct ieee80211com *ic, int hdrsize,
378 	struct ieee80211_key *key, struct mbuf *m)
379 {
380 #define	TO_BE_RECLAIMED	(sizeof(struct ether_header) - sizeof(struct llc))
381 	int needed_space = hdrsize;
382 
383 	if (key != NULL) {
384 		/* XXX belongs in crypto code? */
385 		needed_space += key->wk_cipher->ic_header;
386 		/* XXX frags */
387 		/*
388 		 * When crypto is being done in the host we must insure
389 		 * the data are writable for the cipher routines; clone
390 		 * a writable mbuf chain.
391 		 * XXX handle SWMIC specially
392 		 */
393 		if (key->wk_flags & (IEEE80211_KEY_SWCRYPT|IEEE80211_KEY_SWMIC)) {
394 			m = m_unshare(m, M_NOWAIT);
395 			if (m == NULL) {
396 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
397 				    "%s: cannot get writable mbuf\n", __func__);
398 				ic->ic_stats.is_tx_nobuf++; /* XXX new stat */
399 				return NULL;
400 			}
401 		}
402 	}
403 	/*
404 	 * We know we are called just before stripping an Ethernet
405 	 * header and prepending an LLC header.  This means we know
406 	 * there will be
407 	 *	sizeof(struct ether_header) - sizeof(struct llc)
408 	 * bytes recovered to which we need additional space for the
409 	 * 802.11 header and any crypto header.
410 	 */
411 	/* XXX check trailing space and copy instead? */
412 	if (M_LEADINGSPACE(m) < needed_space - TO_BE_RECLAIMED) {
413 		struct mbuf *n = m_gethdr(M_NOWAIT, m->m_type);
414 		if (n == NULL) {
415 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
416 			    "%s: cannot expand storage\n", __func__);
417 			ic->ic_stats.is_tx_nobuf++;
418 			m_freem(m);
419 			return NULL;
420 		}
421 		KASSERT(needed_space <= MHLEN,
422 		    ("not enough room, need %u got %zu\n", needed_space, MHLEN));
423 		/*
424 		 * Setup new mbuf to have leading space to prepend the
425 		 * 802.11 header and any crypto header bits that are
426 		 * required (the latter are added when the driver calls
427 		 * back to ieee80211_crypto_encap to do crypto encapsulation).
428 		 */
429 		/* NB: must be first 'cuz it clobbers m_data */
430 		m_move_pkthdr(n, m);
431 		n->m_len = 0;			/* NB: m_gethdr does not set */
432 		n->m_data += needed_space;
433 		/*
434 		 * Pull up Ethernet header to create the expected layout.
435 		 * We could use m_pullup but that's overkill (i.e. we don't
436 		 * need the actual data) and it cannot fail so do it inline
437 		 * for speed.
438 		 */
439 		/* NB: struct ether_header is known to be contiguous */
440 		n->m_len += sizeof(struct ether_header);
441 		m->m_len -= sizeof(struct ether_header);
442 		m->m_data += sizeof(struct ether_header);
443 		/*
444 		 * Replace the head of the chain.
445 		 */
446 		n->m_next = m;
447 		m = n;
448 	}
449 	return m;
450 #undef TO_BE_RECLAIMED
451 }
452 
453 #define	KEY_UNDEFINED(k)	((k).wk_cipher == &ieee80211_cipher_none)
454 /*
455  * Return the transmit key to use in sending a unicast frame.
456  * If a unicast key is set we use that.  When no unicast key is set
457  * we fall back to the default transmit key.
458  */
459 static __inline struct ieee80211_key *
460 ieee80211_crypto_getucastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
461 {
462 	if (KEY_UNDEFINED(ni->ni_ucastkey)) {
463 		if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
464 		    KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
465 			return NULL;
466 		return &ic->ic_nw_keys[ic->ic_def_txkey];
467 	} else {
468 		return &ni->ni_ucastkey;
469 	}
470 }
471 
472 /*
473  * Return the transmit key to use in sending a multicast frame.
474  * Multicast traffic always uses the group key which is installed as
475  * the default tx key.
476  */
477 static __inline struct ieee80211_key *
478 ieee80211_crypto_getmcastkey(struct ieee80211com *ic, struct ieee80211_node *ni)
479 {
480 	if (ic->ic_def_txkey == IEEE80211_KEYIX_NONE ||
481 	    KEY_UNDEFINED(ic->ic_nw_keys[ic->ic_def_txkey]))
482 		return NULL;
483 	return &ic->ic_nw_keys[ic->ic_def_txkey];
484 }
485 
486 /*
487  * Encapsulate an outbound data frame.  The mbuf chain is updated.
488  * If an error is encountered NULL is returned.  The caller is required
489  * to provide a node reference and pullup the ethernet header in the
490  * first mbuf.
491  */
492 struct mbuf *
493 ieee80211_encap(struct ieee80211com *ic, struct mbuf *m,
494 	struct ieee80211_node *ni)
495 {
496 	struct ether_header eh;
497 	struct ieee80211_frame *wh;
498 	struct ieee80211_key *key;
499 	struct llc *llc;
500 	int hdrsize, datalen, addqos;
501 
502 	KASSERT(m->m_len >= sizeof(eh), ("no ethernet header!"));
503 	memcpy(&eh, mtod(m, caddr_t), sizeof(struct ether_header));
504 
505 	/*
506 	 * Insure space for additional headers.  First identify
507 	 * transmit key to use in calculating any buffer adjustments
508 	 * required.  This is also used below to do privacy
509 	 * encapsulation work.  Then calculate the 802.11 header
510 	 * size and any padding required by the driver.
511 	 *
512 	 * Note key may be NULL if we fall back to the default
513 	 * transmit key and that is not set.  In that case the
514 	 * buffer may not be expanded as needed by the cipher
515 	 * routines, but they will/should discard it.
516 	 */
517 	if (ic->ic_flags & IEEE80211_F_PRIVACY) {
518 		if (ic->ic_opmode == IEEE80211_M_STA ||
519 		    !IEEE80211_IS_MULTICAST(eh.ether_dhost))
520 			key = ieee80211_crypto_getucastkey(ic, ni);
521 		else
522 			key = ieee80211_crypto_getmcastkey(ic, ni);
523 		if (key == NULL && eh.ether_type != htons(ETHERTYPE_PAE)) {
524 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_CRYPTO,
525 			    "[%s] no default transmit key (%s) deftxkey %u\n",
526 			    ether_sprintf(eh.ether_dhost), __func__,
527 			    ic->ic_def_txkey);
528 			ic->ic_stats.is_tx_nodefkey++;
529 		}
530 	} else
531 		key = NULL;
532 	/* XXX 4-address format */
533 	/*
534 	 * XXX Some ap's don't handle QoS-encapsulated EAPOL
535 	 * frames so suppress use.  This may be an issue if other
536 	 * ap's require all data frames to be QoS-encapsulated
537 	 * once negotiated in which case we'll need to make this
538 	 * configurable.
539 	 */
540 	addqos = (ni->ni_flags & IEEE80211_NODE_QOS) &&
541 		 eh.ether_type != htons(ETHERTYPE_PAE);
542 	if (addqos)
543 		hdrsize = sizeof(struct ieee80211_qosframe);
544 	else
545 		hdrsize = sizeof(struct ieee80211_frame);
546 	if (ic->ic_flags & IEEE80211_F_DATAPAD)
547 		hdrsize = roundup(hdrsize, sizeof(u_int32_t));
548 	m = ieee80211_mbuf_adjust(ic, hdrsize, key, m);
549 	if (m == NULL) {
550 		/* NB: ieee80211_mbuf_adjust handles msgs+statistics */
551 		goto bad;
552 	}
553 
554 	/* NB: this could be optimized because of ieee80211_mbuf_adjust */
555 	m_adj(m, sizeof(struct ether_header) - sizeof(struct llc));
556 	llc = mtod(m, struct llc *);
557 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
558 	llc->llc_control = LLC_UI;
559 	llc->llc_snap.org_code[0] = 0;
560 	llc->llc_snap.org_code[1] = 0;
561 	llc->llc_snap.org_code[2] = 0;
562 	llc->llc_snap.ether_type = eh.ether_type;
563 	datalen = m->m_pkthdr.len;		/* NB: w/o 802.11 header */
564 
565 	M_PREPEND(m, hdrsize, M_DONTWAIT);
566 	if (m == NULL) {
567 		ic->ic_stats.is_tx_nobuf++;
568 		goto bad;
569 	}
570 	wh = mtod(m, struct ieee80211_frame *);
571 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_DATA;
572 	*(u_int16_t *)wh->i_dur = 0;
573 	switch (ic->ic_opmode) {
574 	case IEEE80211_M_STA:
575 		wh->i_fc[1] = IEEE80211_FC1_DIR_TODS;
576 		IEEE80211_ADDR_COPY(wh->i_addr1, ni->ni_bssid);
577 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
578 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_dhost);
579 		break;
580 	case IEEE80211_M_IBSS:
581 	case IEEE80211_M_AHDEMO:
582 		wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
583 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
584 		IEEE80211_ADDR_COPY(wh->i_addr2, eh.ether_shost);
585 		/*
586 		 * NB: always use the bssid from ic_bss as the
587 		 *     neighbor's may be stale after an ibss merge
588 		 */
589 		IEEE80211_ADDR_COPY(wh->i_addr3, ic->ic_bss->ni_bssid);
590 		break;
591 	case IEEE80211_M_HOSTAP:
592 		wh->i_fc[1] = IEEE80211_FC1_DIR_FROMDS;
593 		IEEE80211_ADDR_COPY(wh->i_addr1, eh.ether_dhost);
594 		IEEE80211_ADDR_COPY(wh->i_addr2, ni->ni_bssid);
595 		IEEE80211_ADDR_COPY(wh->i_addr3, eh.ether_shost);
596 		break;
597 	case IEEE80211_M_MONITOR:
598 		goto bad;
599 	}
600 	if (m->m_flags & M_MORE_DATA)
601 		wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
602 	if (addqos) {
603 		struct ieee80211_qosframe *qwh =
604 			(struct ieee80211_qosframe *) wh;
605 		int ac, tid;
606 
607 		ac = M_WME_GETAC(m);
608 		/* map from access class/queue to 11e header priorty value */
609 		tid = WME_AC_TO_TID(ac);
610 		qwh->i_qos[0] = tid & IEEE80211_QOS_TID;
611 		if (ic->ic_wme.wme_wmeChanParams.cap_wmeParams[ac].wmep_noackPolicy)
612 			qwh->i_qos[0] |= 1 << IEEE80211_QOS_ACKPOLICY_S;
613 		qwh->i_qos[1] = 0;
614 		qwh->i_fc[0] |= IEEE80211_FC0_SUBTYPE_QOS;
615 
616 		*(u_int16_t *)wh->i_seq =
617 		    htole16(ni->ni_txseqs[tid] << IEEE80211_SEQ_SEQ_SHIFT);
618 		ni->ni_txseqs[tid]++;
619 	} else {
620 		*(u_int16_t *)wh->i_seq =
621 		    htole16(ni->ni_txseqs[0] << IEEE80211_SEQ_SEQ_SHIFT);
622 		ni->ni_txseqs[0]++;
623 	}
624 	if (key != NULL) {
625 		/*
626 		 * IEEE 802.1X: send EAPOL frames always in the clear.
627 		 * WPA/WPA2: encrypt EAPOL keys when pairwise keys are set.
628 		 */
629 		if (eh.ether_type != htons(ETHERTYPE_PAE) ||
630 		    ((ic->ic_flags & IEEE80211_F_WPA) &&
631 		     (ic->ic_opmode == IEEE80211_M_STA ?
632 		      !KEY_UNDEFINED(*key) : !KEY_UNDEFINED(ni->ni_ucastkey)))) {
633 			wh->i_fc[1] |= IEEE80211_FC1_WEP;
634 			/* XXX do fragmentation */
635 			if (!ieee80211_crypto_enmic(ic, key, m, 0)) {
636 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_OUTPUT,
637 				    "[%s] enmic failed, discard frame\n",
638 				    ether_sprintf(eh.ether_dhost));
639 				ic->ic_stats.is_crypto_enmicfail++;
640 				goto bad;
641 			}
642 		}
643 	}
644 
645 	IEEE80211_NODE_STAT(ni, tx_data);
646 	IEEE80211_NODE_STAT_ADD(ni, tx_bytes, datalen);
647 
648 	return m;
649 bad:
650 	if (m != NULL)
651 		m_freem(m);
652 	return NULL;
653 }
654 
655 /*
656  * Add a supported rates element id to a frame.
657  */
658 static u_int8_t *
659 ieee80211_add_rates(u_int8_t *frm, const struct ieee80211_rateset *rs)
660 {
661 	int nrates;
662 
663 	*frm++ = IEEE80211_ELEMID_RATES;
664 	nrates = rs->rs_nrates;
665 	if (nrates > IEEE80211_RATE_SIZE)
666 		nrates = IEEE80211_RATE_SIZE;
667 	*frm++ = nrates;
668 	memcpy(frm, rs->rs_rates, nrates);
669 	return frm + nrates;
670 }
671 
672 /*
673  * Add an extended supported rates element id to a frame.
674  */
675 static u_int8_t *
676 ieee80211_add_xrates(u_int8_t *frm, const struct ieee80211_rateset *rs)
677 {
678 	/*
679 	 * Add an extended supported rates element if operating in 11g mode.
680 	 */
681 	if (rs->rs_nrates > IEEE80211_RATE_SIZE) {
682 		int nrates = rs->rs_nrates - IEEE80211_RATE_SIZE;
683 		*frm++ = IEEE80211_ELEMID_XRATES;
684 		*frm++ = nrates;
685 		memcpy(frm, rs->rs_rates + IEEE80211_RATE_SIZE, nrates);
686 		frm += nrates;
687 	}
688 	return frm;
689 }
690 
691 /*
692  * Add an ssid elemet to a frame.
693  */
694 static u_int8_t *
695 ieee80211_add_ssid(u_int8_t *frm, const u_int8_t *ssid, u_int len)
696 {
697 	*frm++ = IEEE80211_ELEMID_SSID;
698 	*frm++ = len;
699 	memcpy(frm, ssid, len);
700 	return frm + len;
701 }
702 
703 /*
704  * Add an erp element to a frame.
705  */
706 static u_int8_t *
707 ieee80211_add_erp(u_int8_t *frm, struct ieee80211com *ic)
708 {
709 	u_int8_t erp;
710 
711 	*frm++ = IEEE80211_ELEMID_ERP;
712 	*frm++ = 1;
713 	erp = 0;
714 	if (ic->ic_nonerpsta != 0)
715 		erp |= IEEE80211_ERP_NON_ERP_PRESENT;
716 	if (ic->ic_flags & IEEE80211_F_USEPROT)
717 		erp |= IEEE80211_ERP_USE_PROTECTION;
718 	if (ic->ic_flags & IEEE80211_F_USEBARKER)
719 		erp |= IEEE80211_ERP_LONG_PREAMBLE;
720 	*frm++ = erp;
721 	return frm;
722 }
723 
724 static u_int8_t *
725 ieee80211_setup_wpa_ie(struct ieee80211com *ic, u_int8_t *ie)
726 {
727 #define	WPA_OUI_BYTES		0x00, 0x50, 0xf2
728 #define	ADDSHORT(frm, v) do {			\
729 	frm[0] = (v) & 0xff;			\
730 	frm[1] = (v) >> 8;			\
731 	frm += 2;				\
732 } while (0)
733 #define	ADDSELECTOR(frm, sel) do {		\
734 	memcpy(frm, sel, 4);			\
735 	frm += 4;				\
736 } while (0)
737 	static const u_int8_t oui[4] = { WPA_OUI_BYTES, WPA_OUI_TYPE };
738 	static const u_int8_t cipher_suite[][4] = {
739 		{ WPA_OUI_BYTES, WPA_CSE_WEP40 },	/* NB: 40-bit */
740 		{ WPA_OUI_BYTES, WPA_CSE_TKIP },
741 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX WRAP */
742 		{ WPA_OUI_BYTES, WPA_CSE_CCMP },
743 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
744 		{ WPA_OUI_BYTES, WPA_CSE_NULL },
745 	};
746 	static const u_int8_t wep104_suite[4] =
747 		{ WPA_OUI_BYTES, WPA_CSE_WEP104 };
748 	static const u_int8_t key_mgt_unspec[4] =
749 		{ WPA_OUI_BYTES, WPA_ASE_8021X_UNSPEC };
750 	static const u_int8_t key_mgt_psk[4] =
751 		{ WPA_OUI_BYTES, WPA_ASE_8021X_PSK };
752 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
753 	u_int8_t *frm = ie;
754 	u_int8_t *selcnt;
755 
756 	*frm++ = IEEE80211_ELEMID_VENDOR;
757 	*frm++ = 0;				/* length filled in below */
758 	memcpy(frm, oui, sizeof(oui));		/* WPA OUI */
759 	frm += sizeof(oui);
760 	ADDSHORT(frm, WPA_VERSION);
761 
762 	/* XXX filter out CKIP */
763 
764 	/* multicast cipher */
765 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
766 	    rsn->rsn_mcastkeylen >= 13)
767 		ADDSELECTOR(frm, wep104_suite);
768 	else
769 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
770 
771 	/* unicast cipher list */
772 	selcnt = frm;
773 	ADDSHORT(frm, 0);			/* selector count */
774 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
775 		selcnt[0]++;
776 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
777 	}
778 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
779 		selcnt[0]++;
780 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
781 	}
782 
783 	/* authenticator selector list */
784 	selcnt = frm;
785 	ADDSHORT(frm, 0);			/* selector count */
786 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
787 		selcnt[0]++;
788 		ADDSELECTOR(frm, key_mgt_unspec);
789 	}
790 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
791 		selcnt[0]++;
792 		ADDSELECTOR(frm, key_mgt_psk);
793 	}
794 
795 	/* optional capabilities */
796 	if (rsn->rsn_caps != 0 && rsn->rsn_caps != RSN_CAP_PREAUTH)
797 		ADDSHORT(frm, rsn->rsn_caps);
798 
799 	/* calculate element length */
800 	ie[1] = frm - ie - 2;
801 	KASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
802 		("WPA IE too big, %u > %zu",
803 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
804 	return frm;
805 #undef ADDSHORT
806 #undef ADDSELECTOR
807 #undef WPA_OUI_BYTES
808 }
809 
810 static u_int8_t *
811 ieee80211_setup_rsn_ie(struct ieee80211com *ic, u_int8_t *ie)
812 {
813 #define	RSN_OUI_BYTES		0x00, 0x0f, 0xac
814 #define	ADDSHORT(frm, v) do {			\
815 	frm[0] = (v) & 0xff;			\
816 	frm[1] = (v) >> 8;			\
817 	frm += 2;				\
818 } while (0)
819 #define	ADDSELECTOR(frm, sel) do {		\
820 	memcpy(frm, sel, 4);			\
821 	frm += 4;				\
822 } while (0)
823 	static const u_int8_t cipher_suite[][4] = {
824 		{ RSN_OUI_BYTES, RSN_CSE_WEP40 },	/* NB: 40-bit */
825 		{ RSN_OUI_BYTES, RSN_CSE_TKIP },
826 		{ RSN_OUI_BYTES, RSN_CSE_WRAP },
827 		{ RSN_OUI_BYTES, RSN_CSE_CCMP },
828 		{ 0x00, 0x00, 0x00, 0x00 },		/* XXX CKIP */
829 		{ RSN_OUI_BYTES, RSN_CSE_NULL },
830 	};
831 	static const u_int8_t wep104_suite[4] =
832 		{ RSN_OUI_BYTES, RSN_CSE_WEP104 };
833 	static const u_int8_t key_mgt_unspec[4] =
834 		{ RSN_OUI_BYTES, RSN_ASE_8021X_UNSPEC };
835 	static const u_int8_t key_mgt_psk[4] =
836 		{ RSN_OUI_BYTES, RSN_ASE_8021X_PSK };
837 	const struct ieee80211_rsnparms *rsn = &ic->ic_bss->ni_rsn;
838 	u_int8_t *frm = ie;
839 	u_int8_t *selcnt;
840 
841 	*frm++ = IEEE80211_ELEMID_RSN;
842 	*frm++ = 0;				/* length filled in below */
843 	ADDSHORT(frm, RSN_VERSION);
844 
845 	/* XXX filter out CKIP */
846 
847 	/* multicast cipher */
848 	if (rsn->rsn_mcastcipher == IEEE80211_CIPHER_WEP &&
849 	    rsn->rsn_mcastkeylen >= 13)
850 		ADDSELECTOR(frm, wep104_suite);
851 	else
852 		ADDSELECTOR(frm, cipher_suite[rsn->rsn_mcastcipher]);
853 
854 	/* unicast cipher list */
855 	selcnt = frm;
856 	ADDSHORT(frm, 0);			/* selector count */
857 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_AES_CCM)) {
858 		selcnt[0]++;
859 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_AES_CCM]);
860 	}
861 	if (rsn->rsn_ucastcipherset & (1<<IEEE80211_CIPHER_TKIP)) {
862 		selcnt[0]++;
863 		ADDSELECTOR(frm, cipher_suite[IEEE80211_CIPHER_TKIP]);
864 	}
865 
866 	/* authenticator selector list */
867 	selcnt = frm;
868 	ADDSHORT(frm, 0);			/* selector count */
869 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_UNSPEC) {
870 		selcnt[0]++;
871 		ADDSELECTOR(frm, key_mgt_unspec);
872 	}
873 	if (rsn->rsn_keymgmtset & WPA_ASE_8021X_PSK) {
874 		selcnt[0]++;
875 		ADDSELECTOR(frm, key_mgt_psk);
876 	}
877 
878 	/* optional capabilities */
879 	ADDSHORT(frm, rsn->rsn_caps);
880 	/* XXX PMKID */
881 
882 	/* calculate element length */
883 	ie[1] = frm - ie - 2;
884 	KASSERT(ie[1]+2 <= sizeof(struct ieee80211_ie_wpa),
885 		("RSN IE too big, %u > %zu",
886 		ie[1]+2, sizeof(struct ieee80211_ie_wpa)));
887 	return frm;
888 #undef ADDSELECTOR
889 #undef ADDSHORT
890 #undef RSN_OUI_BYTES
891 }
892 
893 /*
894  * Add a WPA/RSN element to a frame.
895  */
896 static u_int8_t *
897 ieee80211_add_wpa(u_int8_t *frm, struct ieee80211com *ic)
898 {
899 
900 	KASSERT(ic->ic_flags & IEEE80211_F_WPA, ("no WPA/RSN!"));
901 	if (ic->ic_flags & IEEE80211_F_WPA2)
902 		frm = ieee80211_setup_rsn_ie(ic, frm);
903 	if (ic->ic_flags & IEEE80211_F_WPA1)
904 		frm = ieee80211_setup_wpa_ie(ic, frm);
905 	return frm;
906 }
907 
908 #define	WME_OUI_BYTES		0x00, 0x50, 0xf2
909 /*
910  * Add a WME information element to a frame.
911  */
912 static u_int8_t *
913 ieee80211_add_wme_info(u_int8_t *frm, struct ieee80211_wme_state *wme)
914 {
915 	static const struct ieee80211_wme_info info = {
916 		.wme_id		= IEEE80211_ELEMID_VENDOR,
917 		.wme_len	= sizeof(struct ieee80211_wme_info) - 2,
918 		.wme_oui	= { WME_OUI_BYTES },
919 		.wme_type	= WME_OUI_TYPE,
920 		.wme_subtype	= WME_INFO_OUI_SUBTYPE,
921 		.wme_version	= WME_VERSION,
922 		.wme_info	= 0,
923 	};
924 	memcpy(frm, &info, sizeof(info));
925 	return frm + sizeof(info);
926 }
927 
928 /*
929  * Add a WME parameters element to a frame.
930  */
931 static u_int8_t *
932 ieee80211_add_wme_param(u_int8_t *frm, struct ieee80211_wme_state *wme)
933 {
934 #define	SM(_v, _f)	(((_v) << _f##_S) & _f)
935 #define	ADDSHORT(frm, v) do {			\
936 	frm[0] = (v) & 0xff;			\
937 	frm[1] = (v) >> 8;			\
938 	frm += 2;				\
939 } while (0)
940 	/* NB: this works 'cuz a param has an info at the front */
941 	static const struct ieee80211_wme_info param = {
942 		.wme_id		= IEEE80211_ELEMID_VENDOR,
943 		.wme_len	= sizeof(struct ieee80211_wme_param) - 2,
944 		.wme_oui	= { WME_OUI_BYTES },
945 		.wme_type	= WME_OUI_TYPE,
946 		.wme_subtype	= WME_PARAM_OUI_SUBTYPE,
947 		.wme_version	= WME_VERSION,
948 	};
949 	int i;
950 
951 	memcpy(frm, &param, sizeof(param));
952 	frm += __offsetof(struct ieee80211_wme_info, wme_info);
953 	*frm++ = wme->wme_bssChanParams.cap_info;	/* AC info */
954 	*frm++ = 0;					/* reserved field */
955 	for (i = 0; i < WME_NUM_AC; i++) {
956 		const struct wmeParams *ac =
957 		       &wme->wme_bssChanParams.cap_wmeParams[i];
958 		*frm++ = SM(i, WME_PARAM_ACI)
959 		       | SM(ac->wmep_acm, WME_PARAM_ACM)
960 		       | SM(ac->wmep_aifsn, WME_PARAM_AIFSN)
961 		       ;
962 		*frm++ = SM(ac->wmep_logcwmax, WME_PARAM_LOGCWMAX)
963 		       | SM(ac->wmep_logcwmin, WME_PARAM_LOGCWMIN)
964 		       ;
965 		ADDSHORT(frm, ac->wmep_txopLimit);
966 	}
967 	return frm;
968 #undef SM
969 #undef ADDSHORT
970 }
971 #undef WME_OUI_BYTES
972 
973 /*
974  * Send a probe request frame with the specified ssid
975  * and any optional information element data.
976  */
977 int
978 ieee80211_send_probereq(struct ieee80211_node *ni,
979 	const u_int8_t sa[IEEE80211_ADDR_LEN],
980 	const u_int8_t da[IEEE80211_ADDR_LEN],
981 	const u_int8_t bssid[IEEE80211_ADDR_LEN],
982 	const u_int8_t *ssid, size_t ssidlen,
983 	const void *optie, size_t optielen)
984 {
985 	struct ieee80211com *ic = ni->ni_ic;
986 	enum ieee80211_phymode mode;
987 	struct ieee80211_frame *wh;
988 	struct mbuf *m;
989 	u_int8_t *frm;
990 
991 	/*
992 	 * Hold a reference on the node so it doesn't go away until after
993 	 * the xmit is complete all the way in the driver.  On error we
994 	 * will remove our reference.
995 	 */
996 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
997 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
998 		__func__, __LINE__,
999 		ni, ether_sprintf(ni->ni_macaddr),
1000 		ieee80211_node_refcnt(ni)+1);
1001 	ieee80211_ref_node(ni);
1002 
1003 	/*
1004 	 * prreq frame format
1005 	 *	[tlv] ssid
1006 	 *	[tlv] supported rates
1007 	 *	[tlv] extended supported rates
1008 	 *	[tlv] user-specified ie's
1009 	 */
1010 	m = ieee80211_getmgtframe(&frm,
1011 		 2 + IEEE80211_NWID_LEN
1012 	       + 2 + IEEE80211_RATE_SIZE
1013 	       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1014 	       + (optie != NULL ? optielen : 0)
1015 	);
1016 	if (m == NULL) {
1017 		ic->ic_stats.is_tx_nobuf++;
1018 		ieee80211_free_node(ni);
1019 		return ENOMEM;
1020 	}
1021 
1022 	frm = ieee80211_add_ssid(frm, ssid, ssidlen);
1023 	mode = ieee80211_chan2mode(ic, ic->ic_curchan);
1024 	frm = ieee80211_add_rates(frm, &ic->ic_sup_rates[mode]);
1025 	frm = ieee80211_add_xrates(frm, &ic->ic_sup_rates[mode]);
1026 
1027 	if (optie != NULL) {
1028 		memcpy(frm, optie, optielen);
1029 		frm += optielen;
1030 	}
1031 	m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1032 
1033 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1034 	if (m == NULL)
1035 		return ENOMEM;
1036 	KASSERT(m->m_pkthdr.rcvif == NULL, ("rcvif not null"));
1037 	m->m_pkthdr.rcvif = (void *)ni;
1038 
1039 	wh = mtod(m, struct ieee80211_frame *);
1040 	ieee80211_send_setup(ic, ni, wh,
1041 		IEEE80211_FC0_TYPE_MGT | IEEE80211_FC0_SUBTYPE_PROBE_REQ,
1042 		sa, da, bssid);
1043 	/* XXX power management? */
1044 
1045 	IEEE80211_NODE_STAT(ni, tx_probereq);
1046 	IEEE80211_NODE_STAT(ni, tx_mgmt);
1047 
1048 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_DEBUG | IEEE80211_MSG_DUMPPKTS,
1049 	    "[%s] send probe req on channel %u\n",
1050 	    ether_sprintf(wh->i_addr1),
1051 	    ieee80211_chan2ieee(ic, ic->ic_curchan));
1052 
1053 	IF_ENQUEUE(&ic->ic_mgtq, m);
1054 	if_start(ic->ic_ifp);
1055 	return 0;
1056 }
1057 
1058 /*
1059  * Calculate capability information for mgt frames.
1060  */
1061 static u_int16_t
1062 getcapinfo(struct ieee80211com *ic, struct ieee80211_channel *chan)
1063 {
1064 	u_int16_t capinfo;
1065 
1066 	KASSERT(ic->ic_opmode != IEEE80211_M_STA, ("station mode"));
1067 
1068 	if (ic->ic_opmode == IEEE80211_M_HOSTAP)
1069 		capinfo = IEEE80211_CAPINFO_ESS;
1070 	else if (ic->ic_opmode == IEEE80211_M_IBSS)
1071 		capinfo = IEEE80211_CAPINFO_IBSS;
1072 	else
1073 		capinfo = 0;
1074 	if (ic->ic_flags & IEEE80211_F_PRIVACY)
1075 		capinfo |= IEEE80211_CAPINFO_PRIVACY;
1076 	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1077 	    IEEE80211_IS_CHAN_2GHZ(chan))
1078 		capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1079 	if (ic->ic_flags & IEEE80211_F_SHSLOT)
1080 		capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1081 	return capinfo;
1082 }
1083 
1084 /*
1085  * Send a management frame.  The node is for the destination (or ic_bss
1086  * when in station mode).  Nodes other than ic_bss have their reference
1087  * count bumped to reflect our use for an indeterminant time.
1088  */
1089 int
1090 ieee80211_send_mgmt(struct ieee80211com *ic, struct ieee80211_node *ni,
1091 	int type, int arg)
1092 {
1093 #define	senderr(_x, _v)	do { ic->ic_stats._v++; ret = _x; goto bad; } while (0)
1094 	struct mbuf *m;
1095 	u_int8_t *frm;
1096 	u_int16_t capinfo;
1097 	int has_challenge, is_shared_key, ret, timer, status;
1098 
1099 	KASSERT(ni != NULL, ("null node"));
1100 
1101 	/*
1102 	 * Hold a reference on the node so it doesn't go away until after
1103 	 * the xmit is complete all the way in the driver.  On error we
1104 	 * will remove our reference.
1105 	 */
1106 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_NODE,
1107 		"ieee80211_ref_node (%s:%u) %p<%s> refcnt %d\n",
1108 		__func__, __LINE__,
1109 		ni, ether_sprintf(ni->ni_macaddr),
1110 		ieee80211_node_refcnt(ni)+1);
1111 	ieee80211_ref_node(ni);
1112 
1113 	timer = 0;
1114 	switch (type) {
1115 	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
1116 		/*
1117 		 * probe response frame format
1118 		 *	[8] time stamp
1119 		 *	[2] beacon interval
1120 		 *	[2] cabability information
1121 		 *	[tlv] ssid
1122 		 *	[tlv] supported rates
1123 		 *	[tlv] parameter set (FH/DS)
1124 		 *	[tlv] parameter set (IBSS)
1125 		 *	[tlv] extended rate phy (ERP)
1126 		 *	[tlv] extended supported rates
1127 		 *	[tlv] WPA
1128 		 *	[tlv] WME (optional)
1129 		 */
1130 		m = ieee80211_getmgtframe(&frm,
1131 			 8
1132 		       + sizeof(u_int16_t)
1133 		       + sizeof(u_int16_t)
1134 		       + 2 + IEEE80211_NWID_LEN
1135 		       + 2 + IEEE80211_RATE_SIZE
1136 		       + 7	/* max(7,3) */
1137 		       + 6
1138 		       + 3
1139 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1140 		       /* XXX !WPA1+WPA2 fits w/o a cluster */
1141 		       + (ic->ic_flags & IEEE80211_F_WPA ?
1142 				2*sizeof(struct ieee80211_ie_wpa) : 0)
1143 		       + sizeof(struct ieee80211_wme_param)
1144 		);
1145 		if (m == NULL)
1146 			senderr(ENOMEM, is_tx_nobuf);
1147 
1148 		memset(frm, 0, 8);	/* timestamp should be filled later */
1149 		frm += 8;
1150 		*(u_int16_t *)frm = htole16(ic->ic_bss->ni_intval);
1151 		frm += 2;
1152 		capinfo = getcapinfo(ic, ic->ic_curchan);
1153 		*(u_int16_t *)frm = htole16(capinfo);
1154 		frm += 2;
1155 
1156 		frm = ieee80211_add_ssid(frm, ic->ic_bss->ni_essid,
1157 				ic->ic_bss->ni_esslen);
1158 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1159 
1160 		if (ic->ic_phytype == IEEE80211_T_FH) {
1161                         *frm++ = IEEE80211_ELEMID_FHPARMS;
1162                         *frm++ = 5;
1163                         *frm++ = ni->ni_fhdwell & 0x00ff;
1164                         *frm++ = (ni->ni_fhdwell >> 8) & 0x00ff;
1165                         *frm++ = IEEE80211_FH_CHANSET(
1166 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1167                         *frm++ = IEEE80211_FH_CHANPAT(
1168 			    ieee80211_chan2ieee(ic, ic->ic_curchan));
1169                         *frm++ = ni->ni_fhindex;
1170 		} else {
1171 			*frm++ = IEEE80211_ELEMID_DSPARMS;
1172 			*frm++ = 1;
1173 			*frm++ = ieee80211_chan2ieee(ic, ic->ic_curchan);
1174 		}
1175 
1176 		if (ic->ic_opmode == IEEE80211_M_IBSS) {
1177 			*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1178 			*frm++ = 2;
1179 			*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1180 		}
1181 		if (ic->ic_flags & IEEE80211_F_WPA)
1182 			frm = ieee80211_add_wpa(frm, ic);
1183 		if (ic->ic_curmode == IEEE80211_MODE_11G)
1184 			frm = ieee80211_add_erp(frm, ic);
1185 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1186 		if (ic->ic_flags & IEEE80211_F_WME)
1187 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1188 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1189 		break;
1190 
1191 	case IEEE80211_FC0_SUBTYPE_AUTH:
1192 		status = arg >> 16;
1193 		arg &= 0xffff;
1194 		has_challenge = ((arg == IEEE80211_AUTH_SHARED_CHALLENGE ||
1195 		    arg == IEEE80211_AUTH_SHARED_RESPONSE) &&
1196 		    ni->ni_challenge != NULL);
1197 
1198 		/*
1199 		 * Deduce whether we're doing open authentication or
1200 		 * shared key authentication.  We do the latter if
1201 		 * we're in the middle of a shared key authentication
1202 		 * handshake or if we're initiating an authentication
1203 		 * request and configured to use shared key.
1204 		 */
1205 		is_shared_key = has_challenge ||
1206 		     arg >= IEEE80211_AUTH_SHARED_RESPONSE ||
1207 		     (arg == IEEE80211_AUTH_SHARED_REQUEST &&
1208 		      ic->ic_bss->ni_authmode == IEEE80211_AUTH_SHARED);
1209 
1210 		m = ieee80211_getmgtframe(&frm,
1211 			  3 * sizeof(u_int16_t)
1212 			+ (has_challenge && status == IEEE80211_STATUS_SUCCESS ?
1213 				sizeof(u_int16_t)+IEEE80211_CHALLENGE_LEN : 0)
1214 		);
1215 		if (m == NULL)
1216 			senderr(ENOMEM, is_tx_nobuf);
1217 
1218 		((u_int16_t *)frm)[0] =
1219 		    (is_shared_key) ? htole16(IEEE80211_AUTH_ALG_SHARED)
1220 		                    : htole16(IEEE80211_AUTH_ALG_OPEN);
1221 		((u_int16_t *)frm)[1] = htole16(arg);	/* sequence number */
1222 		((u_int16_t *)frm)[2] = htole16(status);/* status */
1223 
1224 		if (has_challenge && status == IEEE80211_STATUS_SUCCESS) {
1225 			((u_int16_t *)frm)[3] =
1226 			    htole16((IEEE80211_CHALLENGE_LEN << 8) |
1227 			    IEEE80211_ELEMID_CHALLENGE);
1228 			memcpy(&((u_int16_t *)frm)[4], ni->ni_challenge,
1229 			    IEEE80211_CHALLENGE_LEN);
1230 			m->m_pkthdr.len = m->m_len =
1231 				4 * sizeof(u_int16_t) + IEEE80211_CHALLENGE_LEN;
1232 			if (arg == IEEE80211_AUTH_SHARED_RESPONSE) {
1233 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1234 				    "[%s] request encrypt frame (%s)\n",
1235 				    ether_sprintf(ni->ni_macaddr), __func__);
1236 				m->m_flags |= M_LINK0; /* WEP-encrypt, please */
1237 			}
1238 		} else
1239 			m->m_pkthdr.len = m->m_len = 3 * sizeof(u_int16_t);
1240 
1241 		/* XXX not right for shared key */
1242 		if (status == IEEE80211_STATUS_SUCCESS)
1243 			IEEE80211_NODE_STAT(ni, tx_auth);
1244 		else
1245 			IEEE80211_NODE_STAT(ni, tx_auth_fail);
1246 
1247 		if (ic->ic_opmode == IEEE80211_M_STA)
1248 			timer = IEEE80211_TRANS_WAIT;
1249 		break;
1250 
1251 	case IEEE80211_FC0_SUBTYPE_DEAUTH:
1252 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_AUTH,
1253 			"[%s] send station deauthenticate (reason %d)\n",
1254 			ether_sprintf(ni->ni_macaddr), arg);
1255 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1256 		if (m == NULL)
1257 			senderr(ENOMEM, is_tx_nobuf);
1258 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1259 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1260 
1261 		IEEE80211_NODE_STAT(ni, tx_deauth);
1262 		IEEE80211_NODE_STAT_SET(ni, tx_deauth_code, arg);
1263 
1264 		ieee80211_node_unauthorize(ni);		/* port closed */
1265 		break;
1266 
1267 	case IEEE80211_FC0_SUBTYPE_ASSOC_REQ:
1268 	case IEEE80211_FC0_SUBTYPE_REASSOC_REQ:
1269 		/*
1270 		 * asreq frame format
1271 		 *	[2] capability information
1272 		 *	[2] listen interval
1273 		 *	[6*] current AP address (reassoc only)
1274 		 *	[tlv] ssid
1275 		 *	[tlv] supported rates
1276 		 *	[tlv] extended supported rates
1277 		 *	[tlv] WME
1278 		 *	[tlv] user-specified ie's
1279 		 */
1280 		m = ieee80211_getmgtframe(&frm,
1281 			 sizeof(u_int16_t)
1282 		       + sizeof(u_int16_t)
1283 		       + IEEE80211_ADDR_LEN
1284 		       + 2 + IEEE80211_NWID_LEN
1285 		       + 2 + IEEE80211_RATE_SIZE
1286 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1287 		       + sizeof(struct ieee80211_wme_info)
1288 		       + (ic->ic_opt_ie != NULL ? ic->ic_opt_ie_len : 0)
1289 		);
1290 		if (m == NULL)
1291 			senderr(ENOMEM, is_tx_nobuf);
1292 
1293 		KASSERT(ic->ic_opmode == IEEE80211_M_STA,
1294 		    ("wrong mode %u", ic->ic_opmode));
1295 		capinfo = IEEE80211_CAPINFO_ESS;
1296 		if (ic->ic_flags & IEEE80211_F_PRIVACY)
1297 			capinfo |= IEEE80211_CAPINFO_PRIVACY;
1298 		/*
1299 		 * NB: Some 11a AP's reject the request when
1300 		 *     short premable is set.
1301 		 */
1302 		if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
1303 		    IEEE80211_IS_CHAN_2GHZ(ic->ic_curchan))
1304 			capinfo |= IEEE80211_CAPINFO_SHORT_PREAMBLE;
1305 		if ((ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_SLOTTIME) &&
1306 		    (ic->ic_caps & IEEE80211_C_SHSLOT))
1307 			capinfo |= IEEE80211_CAPINFO_SHORT_SLOTTIME;
1308 		*(u_int16_t *)frm = htole16(capinfo);
1309 		frm += 2;
1310 
1311 		*(u_int16_t *)frm = htole16(ic->ic_lintval);
1312 		frm += 2;
1313 
1314 		if (type == IEEE80211_FC0_SUBTYPE_REASSOC_REQ) {
1315 			IEEE80211_ADDR_COPY(frm, ic->ic_bss->ni_bssid);
1316 			frm += IEEE80211_ADDR_LEN;
1317 		}
1318 
1319 		frm = ieee80211_add_ssid(frm, ni->ni_essid, ni->ni_esslen);
1320 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1321 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1322 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1323 			frm = ieee80211_add_wme_info(frm, &ic->ic_wme);
1324 		if (ic->ic_opt_ie != NULL) {
1325 			memcpy(frm, ic->ic_opt_ie, ic->ic_opt_ie_len);
1326 			frm += ic->ic_opt_ie_len;
1327 		}
1328 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1329 
1330 		timer = IEEE80211_TRANS_WAIT;
1331 		break;
1332 
1333 	case IEEE80211_FC0_SUBTYPE_ASSOC_RESP:
1334 	case IEEE80211_FC0_SUBTYPE_REASSOC_RESP:
1335 		/*
1336 		 * asreq frame format
1337 		 *	[2] capability information
1338 		 *	[2] status
1339 		 *	[2] association ID
1340 		 *	[tlv] supported rates
1341 		 *	[tlv] extended supported rates
1342 		 *	[tlv] WME (if enabled and STA enabled)
1343 		 */
1344 		m = ieee80211_getmgtframe(&frm,
1345 			 sizeof(u_int16_t)
1346 		       + sizeof(u_int16_t)
1347 		       + sizeof(u_int16_t)
1348 		       + 2 + IEEE80211_RATE_SIZE
1349 		       + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1350 		       + sizeof(struct ieee80211_wme_param)
1351 		);
1352 		if (m == NULL)
1353 			senderr(ENOMEM, is_tx_nobuf);
1354 
1355 		capinfo = getcapinfo(ic, ic->ic_curchan);
1356 		*(u_int16_t *)frm = htole16(capinfo);
1357 		frm += 2;
1358 
1359 		*(u_int16_t *)frm = htole16(arg);	/* status */
1360 		frm += 2;
1361 
1362 		if (arg == IEEE80211_STATUS_SUCCESS) {
1363 			*(u_int16_t *)frm = htole16(ni->ni_associd);
1364 			IEEE80211_NODE_STAT(ni, tx_assoc);
1365 		} else
1366 			IEEE80211_NODE_STAT(ni, tx_assoc_fail);
1367 		frm += 2;
1368 
1369 		frm = ieee80211_add_rates(frm, &ni->ni_rates);
1370 		frm = ieee80211_add_xrates(frm, &ni->ni_rates);
1371 		if ((ic->ic_flags & IEEE80211_F_WME) && ni->ni_wme_ie != NULL)
1372 			frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1373 		m->m_pkthdr.len = m->m_len = frm - mtod(m, u_int8_t *);
1374 		break;
1375 
1376 	case IEEE80211_FC0_SUBTYPE_DISASSOC:
1377 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ASSOC,
1378 			"[%s] send station disassociate (reason %d)\n",
1379 			ether_sprintf(ni->ni_macaddr), arg);
1380 		m = ieee80211_getmgtframe(&frm, sizeof(u_int16_t));
1381 		if (m == NULL)
1382 			senderr(ENOMEM, is_tx_nobuf);
1383 		*(u_int16_t *)frm = htole16(arg);	/* reason */
1384 		m->m_pkthdr.len = m->m_len = sizeof(u_int16_t);
1385 
1386 		IEEE80211_NODE_STAT(ni, tx_disassoc);
1387 		IEEE80211_NODE_STAT_SET(ni, tx_disassoc_code, arg);
1388 		break;
1389 
1390 	default:
1391 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1392 			"[%s] invalid mgmt frame type %u\n",
1393 			ether_sprintf(ni->ni_macaddr), type);
1394 		senderr(EINVAL, is_tx_unknownmgt);
1395 		/* NOTREACHED */
1396 	}
1397 	ret = ieee80211_mgmt_output(ic, ni, m, type, timer);
1398 	if (ret != 0) {
1399 bad:
1400 		ieee80211_free_node(ni);
1401 	}
1402 	return ret;
1403 #undef senderr
1404 }
1405 
1406 /*
1407  * Allocate a beacon frame and fillin the appropriate bits.
1408  */
1409 struct mbuf *
1410 ieee80211_beacon_alloc(struct ieee80211com *ic, struct ieee80211_node *ni,
1411 	struct ieee80211_beacon_offsets *bo)
1412 {
1413 	struct ifnet *ifp = ic->ic_ifp;
1414 	struct ieee80211_frame *wh;
1415 	struct mbuf *m;
1416 	int pktlen;
1417 	u_int8_t *frm, *efrm;
1418 	u_int16_t capinfo;
1419 	struct ieee80211_rateset *rs;
1420 
1421 	/*
1422 	 * beacon frame format
1423 	 *	[8] time stamp
1424 	 *	[2] beacon interval
1425 	 *	[2] cabability information
1426 	 *	[tlv] ssid
1427 	 *	[tlv] supported rates
1428 	 *	[3] parameter set (DS)
1429 	 *	[tlv] parameter set (IBSS/TIM)
1430 	 *	[tlv] extended rate phy (ERP)
1431 	 *	[tlv] extended supported rates
1432 	 *	[tlv] WME parameters
1433 	 *	[tlv] WPA/RSN parameters
1434 	 * XXX Vendor-specific OIDs (e.g. Atheros)
1435 	 * NB: we allocate the max space required for the TIM bitmap.
1436 	 */
1437 	rs = &ni->ni_rates;
1438 	pktlen =   8					/* time stamp */
1439 		 + sizeof(u_int16_t)			/* beacon interval */
1440 		 + sizeof(u_int16_t)			/* capabilities */
1441 		 + 2 + ni->ni_esslen			/* ssid */
1442 	         + 2 + IEEE80211_RATE_SIZE		/* supported rates */
1443 	         + 2 + 1				/* DS parameters */
1444 		 + 2 + 4 + ic->ic_tim_len		/* DTIM/IBSSPARMS */
1445 		 + 2 + 1				/* ERP */
1446 	         + 2 + (IEEE80211_RATE_MAXSIZE - IEEE80211_RATE_SIZE)
1447 		 + (ic->ic_caps & IEEE80211_C_WME ?	/* WME */
1448 			sizeof(struct ieee80211_wme_param) : 0)
1449 		 + (ic->ic_caps & IEEE80211_C_WPA ?	/* WPA 1+2 */
1450 			2*sizeof(struct ieee80211_ie_wpa) : 0)
1451 		 ;
1452 	m = ieee80211_getmgtframe(&frm, pktlen);
1453 	if (m == NULL) {
1454 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1455 			"%s: cannot get buf; size %u\n", __func__, pktlen);
1456 		ic->ic_stats.is_tx_nobuf++;
1457 		return NULL;
1458 	}
1459 
1460 	memset(frm, 0, 8);	/* XXX timestamp is set by hardware/driver */
1461 	frm += 8;
1462 	*(u_int16_t *)frm = htole16(ni->ni_intval);
1463 	frm += 2;
1464 	capinfo = getcapinfo(ic, ni->ni_chan);
1465 	bo->bo_caps = (u_int16_t *)frm;
1466 	*(u_int16_t *)frm = htole16(capinfo);
1467 	frm += 2;
1468 	*frm++ = IEEE80211_ELEMID_SSID;
1469 	if ((ic->ic_flags & IEEE80211_F_HIDESSID) == 0) {
1470 		*frm++ = ni->ni_esslen;
1471 		memcpy(frm, ni->ni_essid, ni->ni_esslen);
1472 		frm += ni->ni_esslen;
1473 	} else
1474 		*frm++ = 0;
1475 	frm = ieee80211_add_rates(frm, rs);
1476 	if (ic->ic_curmode != IEEE80211_MODE_FH) {
1477 		*frm++ = IEEE80211_ELEMID_DSPARMS;
1478 		*frm++ = 1;
1479 		*frm++ = ieee80211_chan2ieee(ic, ni->ni_chan);
1480 	}
1481 	bo->bo_tim = frm;
1482 	if (ic->ic_opmode == IEEE80211_M_IBSS) {
1483 		*frm++ = IEEE80211_ELEMID_IBSSPARMS;
1484 		*frm++ = 2;
1485 		*frm++ = 0; *frm++ = 0;		/* TODO: ATIM window */
1486 		bo->bo_tim_len = 0;
1487 	} else if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
1488 		struct ieee80211_tim_ie *tie = (struct ieee80211_tim_ie *) frm;
1489 
1490 		tie->tim_ie = IEEE80211_ELEMID_TIM;
1491 		tie->tim_len = 4;	/* length */
1492 		tie->tim_count = 0;	/* DTIM count */
1493 		tie->tim_period = ic->ic_dtim_period;	/* DTIM period */
1494 		tie->tim_bitctl = 0;	/* bitmap control */
1495 		tie->tim_bitmap[0] = 0;	/* Partial Virtual Bitmap */
1496 		frm += sizeof(struct ieee80211_tim_ie);
1497 		bo->bo_tim_len = 1;
1498 	}
1499 	bo->bo_trailer = frm;
1500 	if (ic->ic_flags & IEEE80211_F_WME) {
1501 		bo->bo_wme = frm;
1502 		frm = ieee80211_add_wme_param(frm, &ic->ic_wme);
1503 		ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1504 	}
1505 	if (ic->ic_flags & IEEE80211_F_WPA)
1506 		frm = ieee80211_add_wpa(frm, ic);
1507 	if (ic->ic_curmode == IEEE80211_MODE_11G) {
1508 		bo->bo_erp = frm;
1509 		frm = ieee80211_add_erp(frm, ic);
1510 	}
1511 	efrm = ieee80211_add_xrates(frm, rs);
1512 	bo->bo_trailer_len = efrm - bo->bo_trailer;
1513 	m->m_pkthdr.len = m->m_len = efrm - mtod(m, u_int8_t *);
1514 
1515 	M_PREPEND(m, sizeof(struct ieee80211_frame), M_DONTWAIT);
1516 	KASSERT(m != NULL, ("no space for 802.11 header?"));
1517 	wh = mtod(m, struct ieee80211_frame *);
1518 	wh->i_fc[0] = IEEE80211_FC0_VERSION_0 | IEEE80211_FC0_TYPE_MGT |
1519 	    IEEE80211_FC0_SUBTYPE_BEACON;
1520 	wh->i_fc[1] = IEEE80211_FC1_DIR_NODS;
1521 	*(u_int16_t *)wh->i_dur = 0;
1522 	IEEE80211_ADDR_COPY(wh->i_addr1, ifp->if_broadcastaddr);
1523 	IEEE80211_ADDR_COPY(wh->i_addr2, ic->ic_myaddr);
1524 	IEEE80211_ADDR_COPY(wh->i_addr3, ni->ni_bssid);
1525 	*(u_int16_t *)wh->i_seq = 0;
1526 
1527 	return m;
1528 }
1529 
1530 /*
1531  * Update the dynamic parts of a beacon frame based on the current state.
1532  */
1533 int
1534 ieee80211_beacon_update(struct ieee80211com *ic, struct ieee80211_node *ni,
1535 	struct ieee80211_beacon_offsets *bo, struct mbuf *m, int mcast)
1536 {
1537 	int len_changed = 0;
1538 	u_int16_t capinfo;
1539 
1540 	IEEE80211_BEACON_LOCK(ic);
1541 	/* XXX faster to recalculate entirely or just changes? */
1542 	capinfo = getcapinfo(ic, ni->ni_chan);
1543 	*bo->bo_caps = htole16(capinfo);
1544 
1545 	if (ic->ic_flags & IEEE80211_F_WME) {
1546 		struct ieee80211_wme_state *wme = &ic->ic_wme;
1547 
1548 		/*
1549 		 * Check for agressive mode change.  When there is
1550 		 * significant high priority traffic in the BSS
1551 		 * throttle back BE traffic by using conservative
1552 		 * parameters.  Otherwise BE uses agressive params
1553 		 * to optimize performance of legacy/non-QoS traffic.
1554 		 */
1555 		if (wme->wme_flags & WME_F_AGGRMODE) {
1556 			if (wme->wme_hipri_traffic >
1557 			    wme->wme_hipri_switch_thresh) {
1558 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1559 				    "%s: traffic %u, disable aggressive mode\n",
1560 				    __func__, wme->wme_hipri_traffic);
1561 				wme->wme_flags &= ~WME_F_AGGRMODE;
1562 				ieee80211_wme_updateparams_locked(ic);
1563 				wme->wme_hipri_traffic =
1564 					wme->wme_hipri_switch_hysteresis;
1565 			} else
1566 				wme->wme_hipri_traffic = 0;
1567 		} else {
1568 			if (wme->wme_hipri_traffic <=
1569 			    wme->wme_hipri_switch_thresh) {
1570 				IEEE80211_DPRINTF(ic, IEEE80211_MSG_WME,
1571 				    "%s: traffic %u, enable aggressive mode\n",
1572 				    __func__, wme->wme_hipri_traffic);
1573 				wme->wme_flags |= WME_F_AGGRMODE;
1574 				ieee80211_wme_updateparams_locked(ic);
1575 				wme->wme_hipri_traffic = 0;
1576 			} else
1577 				wme->wme_hipri_traffic =
1578 					wme->wme_hipri_switch_hysteresis;
1579 		}
1580 		if (ic->ic_flags & IEEE80211_F_WMEUPDATE) {
1581 			(void) ieee80211_add_wme_param(bo->bo_wme, wme);
1582 			ic->ic_flags &= ~IEEE80211_F_WMEUPDATE;
1583 		}
1584 	}
1585 
1586 	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {	/* NB: no IBSS support*/
1587 		struct ieee80211_tim_ie *tie =
1588 			(struct ieee80211_tim_ie *) bo->bo_tim;
1589 		if (ic->ic_flags & IEEE80211_F_TIMUPDATE) {
1590 			u_int timlen, timoff, i;
1591 			/*
1592 			 * ATIM/DTIM needs updating.  If it fits in the
1593 			 * current space allocated then just copy in the
1594 			 * new bits.  Otherwise we need to move any trailing
1595 			 * data to make room.  Note that we know there is
1596 			 * contiguous space because ieee80211_beacon_allocate
1597 			 * insures there is space in the mbuf to write a
1598 			 * maximal-size virtual bitmap (based on ic_max_aid).
1599 			 */
1600 			/*
1601 			 * Calculate the bitmap size and offset, copy any
1602 			 * trailer out of the way, and then copy in the
1603 			 * new bitmap and update the information element.
1604 			 * Note that the tim bitmap must contain at least
1605 			 * one byte and any offset must be even.
1606 			 */
1607 			if (ic->ic_ps_pending != 0) {
1608 				timoff = 128;		/* impossibly large */
1609 				for (i = 0; i < ic->ic_tim_len; i++)
1610 					if (ic->ic_tim_bitmap[i]) {
1611 						timoff = i &~ 1;
1612 						break;
1613 					}
1614 				KASSERT(timoff != 128, ("tim bitmap empty!"));
1615 				for (i = ic->ic_tim_len-1; i >= timoff; i--)
1616 					if (ic->ic_tim_bitmap[i])
1617 						break;
1618 				timlen = 1 + (i - timoff);
1619 			} else {
1620 				timoff = 0;
1621 				timlen = 1;
1622 			}
1623 			if (timlen != bo->bo_tim_len) {
1624 				/* copy up/down trailer */
1625 				int adjust = tie->tim_bitmap+timlen
1626 					   - bo->bo_trailer;
1627 				ovbcopy(bo->bo_trailer, bo->bo_trailer+adjust,
1628 					bo->bo_trailer_len);
1629 				bo->bo_trailer += adjust;
1630 				bo->bo_wme += adjust;
1631 				bo->bo_erp += adjust;
1632 				bo->bo_tim_len = timlen;
1633 
1634 				/* update information element */
1635 				tie->tim_len = 3 + timlen;
1636 				tie->tim_bitctl = timoff;
1637 				len_changed = 1;
1638 			}
1639 			memcpy(tie->tim_bitmap, ic->ic_tim_bitmap + timoff,
1640 				bo->bo_tim_len);
1641 
1642 			ic->ic_flags &= ~IEEE80211_F_TIMUPDATE;
1643 
1644 			IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1645 				"%s: TIM updated, pending %u, off %u, len %u\n",
1646 				__func__, ic->ic_ps_pending, timoff, timlen);
1647 		}
1648 		/* count down DTIM period */
1649 		if (tie->tim_count == 0)
1650 			tie->tim_count = tie->tim_period - 1;
1651 		else
1652 			tie->tim_count--;
1653 		/* update state for buffered multicast frames on DTIM */
1654 		if (mcast && tie->tim_count == 0)
1655 			tie->tim_bitctl |= 1;
1656 		else
1657 			tie->tim_bitctl &= ~1;
1658 		if (ic->ic_flags_ext & IEEE80211_FEXT_ERPUPDATE) {
1659 			/*
1660 			 * ERP element needs updating.
1661 			 */
1662 			(void) ieee80211_add_erp(bo->bo_erp, ic);
1663 			ic->ic_flags_ext &= ~IEEE80211_FEXT_ERPUPDATE;
1664 		}
1665 	}
1666 	IEEE80211_BEACON_UNLOCK(ic);
1667 
1668 	return len_changed;
1669 }
1670 
1671 /*
1672  * Save an outbound packet for a node in power-save sleep state.
1673  * The new packet is placed on the node's saved queue, and the TIM
1674  * is changed, if necessary.
1675  */
1676 void
1677 ieee80211_pwrsave(struct ieee80211com *ic, struct ieee80211_node *ni,
1678 		  struct mbuf *m)
1679 {
1680 	int qlen, age;
1681 
1682 	IEEE80211_NODE_SAVEQ_LOCK(ni);
1683 	if (_IF_QFULL(&ni->ni_savedq)) {
1684 		_IF_DROP(&ni->ni_savedq);
1685 		IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1686 		IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
1687 			"[%s] pwr save q overflow, drops %d (size %d)\n",
1688 			ether_sprintf(ni->ni_macaddr),
1689 			ni->ni_savedq.ifq_drops, IEEE80211_PS_MAX_QUEUE);
1690 #ifdef IEEE80211_DEBUG
1691 		if (ieee80211_msg_dumppkts(ic))
1692 			ieee80211_dump_pkt(mtod(m, caddr_t), m->m_len, -1, -1);
1693 #endif
1694 		m_freem(m);
1695 		return;
1696 	}
1697 	/*
1698 	 * Tag the frame with it's expiry time and insert
1699 	 * it in the queue.  The aging interval is 4 times
1700 	 * the listen interval specified by the station.
1701 	 * Frames that sit around too long are reclaimed
1702 	 * using this information.
1703 	 */
1704 	/* XXX handle overflow? */
1705 	age = ((ni->ni_intval * ic->ic_bintval) << 2) / 1024; /* TU -> secs */
1706 	_IEEE80211_NODE_SAVEQ_ENQUEUE(ni, m, qlen, age);
1707 	IEEE80211_NODE_SAVEQ_UNLOCK(ni);
1708 
1709 	IEEE80211_DPRINTF(ic, IEEE80211_MSG_POWER,
1710 		"[%s] save frame with age %d, %u now queued\n",
1711 		ether_sprintf(ni->ni_macaddr), age, qlen);
1712 
1713 	if (qlen == 1)
1714 		ic->ic_set_tim(ni, 1);
1715 }
1716