xref: /openbsd-src/sys/net80211/ieee80211.c (revision 898184e3e61f9129feb5978fad5a8c6865f00b92)
1 /*	$OpenBSD: ieee80211.c,v 1.39 2010/08/07 03:50:02 krw Exp $	*/
2 /*	$NetBSD: ieee80211.c,v 1.19 2004/06/06 05:45:29 dyoung Exp $	*/
3 
4 /*-
5  * Copyright (c) 2001 Atsushi Onoe
6  * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of the author may not be used to endorse or promote products
18  *    derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 /*
33  * IEEE 802.11 generic handler
34  */
35 
36 #include "bpfilter.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/socket.h>
43 #include <sys/sockio.h>
44 #include <sys/endian.h>
45 #include <sys/errno.h>
46 #include <sys/proc.h>
47 #include <sys/sysctl.h>
48 
49 #include <net/if.h>
50 #include <net/if_dl.h>
51 #include <net/if_media.h>
52 #include <net/if_arp.h>
53 #include <net/if_llc.h>
54 
55 #if NBPFILTER > 0
56 #include <net/bpf.h>
57 #endif
58 
59 #ifdef INET
60 #include <netinet/in.h>
61 #include <netinet/if_ether.h>
62 #endif
63 
64 #include <net80211/ieee80211_var.h>
65 #include <net80211/ieee80211_priv.h>
66 
67 #ifdef IEEE80211_DEBUG
68 int	ieee80211_debug = 0;
69 #endif
70 
71 int ieee80211_cache_size = IEEE80211_CACHE_SIZE;
72 
73 struct ieee80211com_head ieee80211com_head =
74     LIST_HEAD_INITIALIZER(ieee80211com_head);
75 
76 void ieee80211_setbasicrates(struct ieee80211com *);
77 int ieee80211_findrate(struct ieee80211com *, enum ieee80211_phymode, int);
78 
79 void
80 ieee80211_ifattach(struct ifnet *ifp)
81 {
82 	struct ieee80211com *ic = (void *)ifp;
83 	struct ieee80211_channel *c;
84 	int i;
85 
86 	memcpy(((struct arpcom *)ifp)->ac_enaddr, ic->ic_myaddr,
87 		ETHER_ADDR_LEN);
88 	ether_ifattach(ifp);
89 
90 	ifp->if_output = ieee80211_output;
91 
92 #if NBPFILTER > 0
93 	bpfattach(&ic->ic_rawbpf, ifp, DLT_IEEE802_11,
94 	    sizeof(struct ieee80211_frame_addr4));
95 #endif
96 	ieee80211_crypto_attach(ifp);
97 
98 	/*
99 	 * Fill in 802.11 available channel set, mark
100 	 * all available channels as active, and pick
101 	 * a default channel if not already specified.
102 	 */
103 	memset(ic->ic_chan_avail, 0, sizeof(ic->ic_chan_avail));
104 	ic->ic_modecaps |= 1<<IEEE80211_MODE_AUTO;
105 	for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
106 		c = &ic->ic_channels[i];
107 		if (c->ic_flags) {
108 			/*
109 			 * Verify driver passed us valid data.
110 			 */
111 			if (i != ieee80211_chan2ieee(ic, c)) {
112 				printf("%s: bad channel ignored; "
113 					"freq %u flags %x number %u\n",
114 					ifp->if_xname, c->ic_freq, c->ic_flags,
115 					i);
116 				c->ic_flags = 0;	/* NB: remove */
117 				continue;
118 			}
119 			setbit(ic->ic_chan_avail, i);
120 			/*
121 			 * Identify mode capabilities.
122 			 */
123 			if (IEEE80211_IS_CHAN_A(c))
124 				ic->ic_modecaps |= 1<<IEEE80211_MODE_11A;
125 			if (IEEE80211_IS_CHAN_B(c))
126 				ic->ic_modecaps |= 1<<IEEE80211_MODE_11B;
127 			if (IEEE80211_IS_CHAN_PUREG(c))
128 				ic->ic_modecaps |= 1<<IEEE80211_MODE_11G;
129 			if (IEEE80211_IS_CHAN_T(c))
130 				ic->ic_modecaps |= 1<<IEEE80211_MODE_TURBO;
131 		}
132 	}
133 	/* validate ic->ic_curmode */
134 	if ((ic->ic_modecaps & (1<<ic->ic_curmode)) == 0)
135 		ic->ic_curmode = IEEE80211_MODE_AUTO;
136 	ic->ic_des_chan = IEEE80211_CHAN_ANYC;	/* any channel is ok */
137 	ic->ic_scan_lock = IEEE80211_SCAN_UNLOCKED;
138 
139 	/* IEEE 802.11 defines a MTU >= 2290 */
140 	ifp->if_capabilities |= IFCAP_VLAN_MTU;
141 
142 	ieee80211_setbasicrates(ic);
143 	(void)ieee80211_setmode(ic, ic->ic_curmode);
144 
145 	if (ic->ic_lintval == 0)
146 		ic->ic_lintval = 100;		/* default sleep */
147 	ic->ic_bmisstimeout = 7*ic->ic_lintval;	/* default 7 beacons */
148 	ic->ic_dtim_period = 1;	/* all TIMs are DTIMs */
149 
150 	LIST_INSERT_HEAD(&ieee80211com_head, ic, ic_list);
151 	ieee80211_node_attach(ifp);
152 	ieee80211_proto_attach(ifp);
153 
154 	if_addgroup(ifp, "wlan");
155 	ifp->if_priority = IF_WIRELESS_DEFAULT_PRIORITY;
156 }
157 
158 void
159 ieee80211_ifdetach(struct ifnet *ifp)
160 {
161 	struct ieee80211com *ic = (void *)ifp;
162 
163 	ieee80211_proto_detach(ifp);
164 	ieee80211_crypto_detach(ifp);
165 	ieee80211_node_detach(ifp);
166 	LIST_REMOVE(ic, ic_list);
167 	ifmedia_delete_instance(&ic->ic_media, IFM_INST_ANY);
168 	ether_ifdetach(ifp);
169 }
170 
171 /*
172  * Convert MHz frequency to IEEE channel number.
173  */
174 u_int
175 ieee80211_mhz2ieee(u_int freq, u_int flags)
176 {
177 	if (flags & IEEE80211_CHAN_2GHZ) {	/* 2GHz band */
178 		if (freq == 2484)
179 			return 14;
180 		if (freq < 2484)
181 			return (freq - 2407) / 5;
182 		else
183 			return 15 + ((freq - 2512) / 20);
184 	} else if (flags & IEEE80211_CHAN_5GHZ) {	/* 5GHz band */
185 		return (freq - 5000) / 5;
186 	} else {				/* either, guess */
187 		if (freq == 2484)
188 			return 14;
189 		if (freq < 2484)
190 			return (freq - 2407) / 5;
191 		if (freq < 5000)
192 			return 15 + ((freq - 2512) / 20);
193 		return (freq - 5000) / 5;
194 	}
195 }
196 
197 /*
198  * Convert channel to IEEE channel number.
199  */
200 u_int
201 ieee80211_chan2ieee(struct ieee80211com *ic, const struct ieee80211_channel *c)
202 {
203 	struct ifnet *ifp = &ic->ic_if;
204 	if (ic->ic_channels <= c && c <= &ic->ic_channels[IEEE80211_CHAN_MAX])
205 		return c - ic->ic_channels;
206 	else if (c == IEEE80211_CHAN_ANYC)
207 		return IEEE80211_CHAN_ANY;
208 	else if (c != NULL) {
209 		printf("%s: invalid channel freq %u flags %x\n",
210 			ifp->if_xname, c->ic_freq, c->ic_flags);
211 		return 0;		/* XXX */
212 	} else {
213 		printf("%s: invalid channel (NULL)\n", ifp->if_xname);
214 		return 0;		/* XXX */
215 	}
216 }
217 
218 /*
219  * Convert IEEE channel number to MHz frequency.
220  */
221 u_int
222 ieee80211_ieee2mhz(u_int chan, u_int flags)
223 {
224 	if (flags & IEEE80211_CHAN_2GHZ) {	/* 2GHz band */
225 		if (chan == 14)
226 			return 2484;
227 		if (chan < 14)
228 			return 2407 + chan*5;
229 		else
230 			return 2512 + ((chan-15)*20);
231 	} else if (flags & IEEE80211_CHAN_5GHZ) {/* 5GHz band */
232 		return 5000 + (chan*5);
233 	} else {				/* either, guess */
234 		if (chan == 14)
235 			return 2484;
236 		if (chan < 14)			/* 0-13 */
237 			return 2407 + chan*5;
238 		if (chan < 27)			/* 15-26 */
239 			return 2512 + ((chan-15)*20);
240 		return 5000 + (chan*5);
241 	}
242 }
243 
244 /*
245  * Setup the media data structures according to the channel and
246  * rate tables.  This must be called by the driver after
247  * ieee80211_attach and before most anything else.
248  */
249 void
250 ieee80211_media_init(struct ifnet *ifp,
251 	ifm_change_cb_t media_change, ifm_stat_cb_t media_stat)
252 {
253 #define	ADD(_ic, _s, _o) \
254 	ifmedia_add(&(_ic)->ic_media, \
255 		IFM_MAKEWORD(IFM_IEEE80211, (_s), (_o), 0), 0, NULL)
256 	struct ieee80211com *ic = (void *)ifp;
257 	struct ifmediareq imr;
258 	int i, j, mode, rate, maxrate, mword, mopt, r;
259 	const struct ieee80211_rateset *rs;
260 	struct ieee80211_rateset allrates;
261 
262 	/*
263 	 * Do late attach work that must wait for any subclass
264 	 * (i.e. driver) work such as overriding methods.
265 	 */
266 	ieee80211_node_lateattach(ifp);
267 
268 	/*
269 	 * Fill in media characteristics.
270 	 */
271 	ifmedia_init(&ic->ic_media, 0, media_change, media_stat);
272 	maxrate = 0;
273 	memset(&allrates, 0, sizeof(allrates));
274 	for (mode = IEEE80211_MODE_AUTO; mode < IEEE80211_MODE_MAX; mode++) {
275 		static const u_int mopts[] = {
276 			IFM_AUTO,
277 			IFM_IEEE80211_11A,
278 			IFM_IEEE80211_11B,
279 			IFM_IEEE80211_11G,
280 			IFM_IEEE80211_11A | IFM_IEEE80211_TURBO,
281 		};
282 		if ((ic->ic_modecaps & (1<<mode)) == 0)
283 			continue;
284 		mopt = mopts[mode];
285 		ADD(ic, IFM_AUTO, mopt);	/* e.g. 11a auto */
286 #ifndef IEEE80211_STA_ONLY
287 		if (ic->ic_caps & IEEE80211_C_IBSS)
288 			ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_IBSS);
289 		if (ic->ic_caps & IEEE80211_C_HOSTAP)
290 			ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_HOSTAP);
291 		if (ic->ic_caps & IEEE80211_C_AHDEMO)
292 			ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_ADHOC);
293 #endif
294 		if (ic->ic_caps & IEEE80211_C_MONITOR)
295 			ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_MONITOR);
296 		if (mode == IEEE80211_MODE_AUTO)
297 			continue;
298 		rs = &ic->ic_sup_rates[mode];
299 		for (i = 0; i < rs->rs_nrates; i++) {
300 			rate = rs->rs_rates[i];
301 			mword = ieee80211_rate2media(ic, rate, mode);
302 			if (mword == 0)
303 				continue;
304 			ADD(ic, mword, mopt);
305 #ifndef IEEE80211_STA_ONLY
306 			if (ic->ic_caps & IEEE80211_C_IBSS)
307 				ADD(ic, mword, mopt | IFM_IEEE80211_IBSS);
308 			if (ic->ic_caps & IEEE80211_C_HOSTAP)
309 				ADD(ic, mword, mopt | IFM_IEEE80211_HOSTAP);
310 			if (ic->ic_caps & IEEE80211_C_AHDEMO)
311 				ADD(ic, mword, mopt | IFM_IEEE80211_ADHOC);
312 #endif
313 			if (ic->ic_caps & IEEE80211_C_MONITOR)
314 				ADD(ic, mword, mopt | IFM_IEEE80211_MONITOR);
315 			/*
316 			 * Add rate to the collection of all rates.
317 			 */
318 			r = rate & IEEE80211_RATE_VAL;
319 			for (j = 0; j < allrates.rs_nrates; j++)
320 				if (allrates.rs_rates[j] == r)
321 					break;
322 			if (j == allrates.rs_nrates) {
323 				/* unique, add to the set */
324 				allrates.rs_rates[j] = r;
325 				allrates.rs_nrates++;
326 			}
327 			rate = (rate & IEEE80211_RATE_VAL) / 2;
328 			if (rate > maxrate)
329 				maxrate = rate;
330 		}
331 	}
332 	for (i = 0; i < allrates.rs_nrates; i++) {
333 		mword = ieee80211_rate2media(ic, allrates.rs_rates[i],
334 				IEEE80211_MODE_AUTO);
335 		if (mword == 0)
336 			continue;
337 		mword = IFM_SUBTYPE(mword);	/* remove media options */
338 		ADD(ic, mword, 0);
339 #ifndef IEEE80211_STA_ONLY
340 		if (ic->ic_caps & IEEE80211_C_IBSS)
341 			ADD(ic, mword, IFM_IEEE80211_IBSS);
342 		if (ic->ic_caps & IEEE80211_C_HOSTAP)
343 			ADD(ic, mword, IFM_IEEE80211_HOSTAP);
344 		if (ic->ic_caps & IEEE80211_C_AHDEMO)
345 			ADD(ic, mword, IFM_IEEE80211_ADHOC);
346 #endif
347 		if (ic->ic_caps & IEEE80211_C_MONITOR)
348 			ADD(ic, mword, IFM_IEEE80211_MONITOR);
349 	}
350 	ieee80211_media_status(ifp, &imr);
351 	ifmedia_set(&ic->ic_media, imr.ifm_active);
352 
353 	if (maxrate)
354 		ifp->if_baudrate = IF_Mbps(maxrate);
355 
356 #undef ADD
357 }
358 
359 int
360 ieee80211_findrate(struct ieee80211com *ic, enum ieee80211_phymode mode,
361     int rate)
362 {
363 #define	IEEERATE(_ic,_m,_i) \
364 	((_ic)->ic_sup_rates[_m].rs_rates[_i] & IEEE80211_RATE_VAL)
365 	int i, nrates = ic->ic_sup_rates[mode].rs_nrates;
366 	for (i = 0; i < nrates; i++)
367 		if (IEEERATE(ic, mode, i) == rate)
368 			return i;
369 	return -1;
370 #undef IEEERATE
371 }
372 
373 /*
374  * Handle a media change request.
375  */
376 int
377 ieee80211_media_change(struct ifnet *ifp)
378 {
379 	struct ieee80211com *ic = (void *)ifp;
380 	struct ifmedia_entry *ime;
381 	enum ieee80211_opmode newopmode;
382 	enum ieee80211_phymode newphymode;
383 	int i, j, newrate, error = 0;
384 
385 	ime = ic->ic_media.ifm_cur;
386 	/*
387 	 * First, identify the phy mode.
388 	 */
389 	switch (IFM_MODE(ime->ifm_media)) {
390 	case IFM_IEEE80211_11A:
391 		newphymode = IEEE80211_MODE_11A;
392 		break;
393 	case IFM_IEEE80211_11B:
394 		newphymode = IEEE80211_MODE_11B;
395 		break;
396 	case IFM_IEEE80211_11G:
397 		newphymode = IEEE80211_MODE_11G;
398 		break;
399 	case IFM_AUTO:
400 		newphymode = IEEE80211_MODE_AUTO;
401 		break;
402 	default:
403 		return EINVAL;
404 	}
405 	/*
406 	 * Turbo mode is an ``option''.  Eventually it
407 	 * needs to be applied to 11g too.
408 	 */
409 	if (ime->ifm_media & IFM_IEEE80211_TURBO) {
410 		if (newphymode != IEEE80211_MODE_11A)
411 			return EINVAL;
412 		newphymode = IEEE80211_MODE_TURBO;
413 	}
414 	/*
415 	 * Validate requested mode is available.
416 	 */
417 	if ((ic->ic_modecaps & (1<<newphymode)) == 0)
418 		return EINVAL;
419 
420 	/*
421 	 * Next, the fixed/variable rate.
422 	 */
423 	i = -1;
424 	if (IFM_SUBTYPE(ime->ifm_media) != IFM_AUTO) {
425 		/*
426 		 * Convert media subtype to rate.
427 		 */
428 		newrate = ieee80211_media2rate(ime->ifm_media);
429 		if (newrate == 0)
430 			return EINVAL;
431 		/*
432 		 * Check the rate table for the specified/current phy.
433 		 */
434 		if (newphymode == IEEE80211_MODE_AUTO) {
435 			/*
436 			 * In autoselect mode search for the rate.
437 			 */
438 			for (j = IEEE80211_MODE_11A;
439 			     j < IEEE80211_MODE_MAX; j++) {
440 				if ((ic->ic_modecaps & (1<<j)) == 0)
441 					continue;
442 				i = ieee80211_findrate(ic, j, newrate);
443 				if (i != -1) {
444 					/* lock mode too */
445 					newphymode = j;
446 					break;
447 				}
448 			}
449 		} else {
450 			i = ieee80211_findrate(ic, newphymode, newrate);
451 		}
452 		if (i == -1)			/* mode/rate mismatch */
453 			return EINVAL;
454 	}
455 	/* NB: defer rate setting to later */
456 
457 	/*
458 	 * Deduce new operating mode but don't install it just yet.
459 	 */
460 #ifndef IEEE80211_STA_ONLY
461 	if (ime->ifm_media & IFM_IEEE80211_ADHOC)
462 		newopmode = IEEE80211_M_AHDEMO;
463 	else if (ime->ifm_media & IFM_IEEE80211_HOSTAP)
464 		newopmode = IEEE80211_M_HOSTAP;
465 	else if (ime->ifm_media & IFM_IEEE80211_IBSS)
466 		newopmode = IEEE80211_M_IBSS;
467 	else
468 #endif
469 	if (ime->ifm_media & IFM_IEEE80211_MONITOR)
470 		newopmode = IEEE80211_M_MONITOR;
471 	else
472 		newopmode = IEEE80211_M_STA;
473 
474 #ifndef IEEE80211_STA_ONLY
475 	/*
476 	 * Autoselect doesn't make sense when operating as an AP.
477 	 * If no phy mode has been selected, pick one and lock it
478 	 * down so rate tables can be used in forming beacon frames
479 	 * and the like.
480 	 */
481 	if (newopmode == IEEE80211_M_HOSTAP &&
482 	    newphymode == IEEE80211_MODE_AUTO) {
483 		for (j = IEEE80211_MODE_11A; j < IEEE80211_MODE_MAX; j++)
484 			if (ic->ic_modecaps & (1<<j)) {
485 				newphymode = j;
486 				break;
487 			}
488 	}
489 #endif
490 
491 	/*
492 	 * Handle phy mode change.
493 	 */
494 	if (ic->ic_curmode != newphymode) {		/* change phy mode */
495 		error = ieee80211_setmode(ic, newphymode);
496 		if (error != 0)
497 			return error;
498 		error = ENETRESET;
499 	}
500 
501 	/*
502 	 * Committed to changes, install the rate setting.
503 	 */
504 	if (ic->ic_fixed_rate != i) {
505 		ic->ic_fixed_rate = i;			/* set fixed tx rate */
506 		error = ENETRESET;
507 	}
508 
509 	/*
510 	 * Handle operating mode change.
511 	 */
512 	if (ic->ic_opmode != newopmode) {
513 		ic->ic_opmode = newopmode;
514 #ifndef IEEE80211_STA_ONLY
515 		switch (newopmode) {
516 		case IEEE80211_M_AHDEMO:
517 		case IEEE80211_M_HOSTAP:
518 		case IEEE80211_M_STA:
519 		case IEEE80211_M_MONITOR:
520 			ic->ic_flags &= ~IEEE80211_F_IBSSON;
521 			break;
522 		case IEEE80211_M_IBSS:
523 			ic->ic_flags |= IEEE80211_F_IBSSON;
524 			break;
525 		}
526 #endif
527 		/*
528 		 * Yech, slot time may change depending on the
529 		 * operating mode so reset it to be sure everything
530 		 * is setup appropriately.
531 		 */
532 		ieee80211_reset_erp(ic);
533 		error = ENETRESET;
534 	}
535 #ifdef notdef
536 	if (error == 0)
537 		ifp->if_baudrate = ifmedia_baudrate(ime->ifm_media);
538 #endif
539 	return error;
540 }
541 
542 void
543 ieee80211_media_status(struct ifnet *ifp, struct ifmediareq *imr)
544 {
545 	struct ieee80211com *ic = (void *)ifp;
546 	const struct ieee80211_node *ni = NULL;
547 
548 	imr->ifm_status = IFM_AVALID;
549 	imr->ifm_active = IFM_IEEE80211;
550 	if (ic->ic_state == IEEE80211_S_RUN &&
551 	    (ic->ic_opmode != IEEE80211_M_STA ||
552 	     !(ic->ic_flags & IEEE80211_F_RSNON) ||
553 	     ic->ic_bss->ni_port_valid))
554 		imr->ifm_status |= IFM_ACTIVE;
555 	imr->ifm_active |= IFM_AUTO;
556 	switch (ic->ic_opmode) {
557 	case IEEE80211_M_STA:
558 		ni = ic->ic_bss;
559 		/* calculate rate subtype */
560 		imr->ifm_active |= ieee80211_rate2media(ic,
561 			ni->ni_rates.rs_rates[ni->ni_txrate], ic->ic_curmode);
562 		break;
563 #ifndef IEEE80211_STA_ONLY
564 	case IEEE80211_M_IBSS:
565 		imr->ifm_active |= IFM_IEEE80211_IBSS;
566 		break;
567 	case IEEE80211_M_AHDEMO:
568 		imr->ifm_active |= IFM_IEEE80211_ADHOC;
569 		break;
570 	case IEEE80211_M_HOSTAP:
571 		imr->ifm_active |= IFM_IEEE80211_HOSTAP;
572 		break;
573 #endif
574 	case IEEE80211_M_MONITOR:
575 		imr->ifm_active |= IFM_IEEE80211_MONITOR;
576 		break;
577 	default:
578 		break;
579 	}
580 	switch (ic->ic_curmode) {
581 	case IEEE80211_MODE_11A:
582 		imr->ifm_active |= IFM_IEEE80211_11A;
583 		break;
584 	case IEEE80211_MODE_11B:
585 		imr->ifm_active |= IFM_IEEE80211_11B;
586 		break;
587 	case IEEE80211_MODE_11G:
588 		imr->ifm_active |= IFM_IEEE80211_11G;
589 		break;
590 	case IEEE80211_MODE_TURBO:
591 		imr->ifm_active |= IFM_IEEE80211_11A
592 				|  IFM_IEEE80211_TURBO;
593 		break;
594 	}
595 }
596 
597 void
598 ieee80211_watchdog(struct ifnet *ifp)
599 {
600 	struct ieee80211com *ic = (void *)ifp;
601 
602 	if (ic->ic_mgt_timer && --ic->ic_mgt_timer == 0)
603 		ieee80211_new_state(ic, IEEE80211_S_SCAN, -1);
604 
605 	if (ic->ic_mgt_timer != 0)
606 		ifp->if_timer = 1;
607 }
608 
609 const struct ieee80211_rateset ieee80211_std_rateset_11a =
610 	{ 8, { 12, 18, 24, 36, 48, 72, 96, 108 } };
611 
612 const struct ieee80211_rateset ieee80211_std_rateset_11b =
613 	{ 4, { 2, 4, 11, 22 } };
614 
615 const struct ieee80211_rateset ieee80211_std_rateset_11g =
616 	{ 12, { 2, 4, 11, 22, 12, 18, 24, 36, 48, 72, 96, 108 } };
617 
618 /*
619  * Mark the basic rates for the 11g rate table based on the
620  * operating mode.  For real 11g we mark all the 11b rates
621  * and 6, 12, and 24 OFDM.  For 11b compatibility we mark only
622  * 11b rates.  There's also a pseudo 11a-mode used to mark only
623  * the basic OFDM rates.
624  */
625 void
626 ieee80211_setbasicrates(struct ieee80211com *ic)
627 {
628 	static const struct ieee80211_rateset basic[] = {
629 	    { 0 },				/* IEEE80211_MODE_AUTO */
630 	    { 3, { 12, 24, 48 } },		/* IEEE80211_MODE_11A */
631 	    { 2, { 2, 4 } },			/* IEEE80211_MODE_11B */
632 	    { 4, { 2, 4, 11, 22 } },		/* IEEE80211_MODE_11G */
633 	    { 0 },				/* IEEE80211_MODE_TURBO	*/
634 	};
635 	enum ieee80211_phymode mode;
636 	struct ieee80211_rateset *rs;
637 	int i, j;
638 
639 	for (mode = 0; mode < IEEE80211_MODE_MAX; mode++) {
640 		rs = &ic->ic_sup_rates[mode];
641 		for (i = 0; i < rs->rs_nrates; i++) {
642 			rs->rs_rates[i] &= IEEE80211_RATE_VAL;
643 			for (j = 0; j < basic[mode].rs_nrates; j++) {
644 				if (basic[mode].rs_rates[j] ==
645 				    rs->rs_rates[i]) {
646 					rs->rs_rates[i] |=
647 					    IEEE80211_RATE_BASIC;
648 					break;
649 				}
650 			}
651 		}
652 	}
653 }
654 
655 /*
656  * Set the current phy mode and recalculate the active channel
657  * set based on the available channels for this mode.  Also
658  * select a new default/current channel if the current one is
659  * inappropriate for this mode.
660  */
661 int
662 ieee80211_setmode(struct ieee80211com *ic, enum ieee80211_phymode mode)
663 {
664 #define	N(a)	(sizeof(a) / sizeof(a[0]))
665 	struct ifnet *ifp = &ic->ic_if;
666 	static const u_int chanflags[] = {
667 		0,			/* IEEE80211_MODE_AUTO */
668 		IEEE80211_CHAN_A,	/* IEEE80211_MODE_11A */
669 		IEEE80211_CHAN_B,	/* IEEE80211_MODE_11B */
670 		IEEE80211_CHAN_PUREG,	/* IEEE80211_MODE_11G */
671 		IEEE80211_CHAN_T,	/* IEEE80211_MODE_TURBO	*/
672 	};
673 	const struct ieee80211_channel *c;
674 	u_int modeflags;
675 	int i;
676 
677 	/* validate new mode */
678 	if ((ic->ic_modecaps & (1<<mode)) == 0) {
679 		DPRINTF(("mode %u not supported (caps 0x%x)\n",
680 		    mode, ic->ic_modecaps));
681 		return EINVAL;
682 	}
683 
684 	/*
685 	 * Verify at least one channel is present in the available
686 	 * channel list before committing to the new mode.
687 	 */
688 	if (mode >= N(chanflags))
689 		panic("Unexpected mode %u", mode);
690 	modeflags = chanflags[mode];
691 	for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
692 		c = &ic->ic_channels[i];
693 		if (mode == IEEE80211_MODE_AUTO) {
694 			/* ignore turbo channels for autoselect */
695 			if ((c->ic_flags &~ IEEE80211_CHAN_TURBO) != 0)
696 				break;
697 		} else {
698 			if ((c->ic_flags & modeflags) == modeflags)
699 				break;
700 		}
701 	}
702 	if (i > IEEE80211_CHAN_MAX) {
703 		DPRINTF(("no channels found for mode %u\n", mode));
704 		return EINVAL;
705 	}
706 
707 	/*
708 	 * Calculate the active channel set.
709 	 */
710 	memset(ic->ic_chan_active, 0, sizeof(ic->ic_chan_active));
711 	for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
712 		c = &ic->ic_channels[i];
713 		if (mode == IEEE80211_MODE_AUTO) {
714 			/* take anything but pure turbo channels */
715 			if ((c->ic_flags &~ IEEE80211_CHAN_TURBO) != 0)
716 				setbit(ic->ic_chan_active, i);
717 		} else {
718 			if ((c->ic_flags & modeflags) == modeflags)
719 				setbit(ic->ic_chan_active, i);
720 		}
721 	}
722 	/*
723 	 * If no current/default channel is setup or the current
724 	 * channel is wrong for the mode then pick the first
725 	 * available channel from the active list.  This is likely
726 	 * not the right one.
727 	 */
728 	if (ic->ic_ibss_chan == NULL || isclr(ic->ic_chan_active,
729 	    ieee80211_chan2ieee(ic, ic->ic_ibss_chan))) {
730 		for (i = 0; i <= IEEE80211_CHAN_MAX; i++)
731 			if (isset(ic->ic_chan_active, i)) {
732 				ic->ic_ibss_chan = &ic->ic_channels[i];
733 				break;
734 			}
735 		if ((ic->ic_ibss_chan == NULL) || isclr(ic->ic_chan_active,
736 		    ieee80211_chan2ieee(ic, ic->ic_ibss_chan)))
737 			panic("Bad IBSS channel %u",
738 			    ieee80211_chan2ieee(ic, ic->ic_ibss_chan));
739 	}
740 
741 	/*
742 	 * Reset the scan state for the new mode. This avoids scanning
743 	 * of invalid channels, ie. 5GHz channels in 11b mode.
744 	 */
745 	ieee80211_reset_scan(ifp);
746 
747 	ic->ic_curmode = mode;
748 	ieee80211_reset_erp(ic);	/* reset ERP state */
749 
750 	return 0;
751 #undef N
752 }
753 
754 enum ieee80211_phymode
755 ieee80211_next_mode(struct ifnet *ifp)
756 {
757 	struct ieee80211com *ic = (void *)ifp;
758 
759 	if (IFM_MODE(ic->ic_media.ifm_cur->ifm_media) != IFM_AUTO) {
760 		/*
761 		 * Reset the scan state and indicate a wrap around
762 		 * if we're running in a fixed, user-specified phy mode.
763 		 */
764 		ieee80211_reset_scan(ifp);
765 		return (IEEE80211_MODE_AUTO);
766 	}
767 
768 	/*
769 	 * Get the next supported mode
770 	 */
771 	for (++ic->ic_curmode;
772 	    ic->ic_curmode <= IEEE80211_MODE_TURBO;
773 	    ic->ic_curmode++) {
774 		/* Wrap around and ignore turbo mode */
775 		if (ic->ic_curmode >= IEEE80211_MODE_TURBO) {
776 			ic->ic_curmode = IEEE80211_MODE_AUTO;
777 			break;
778 		}
779 
780 		if (ic->ic_modecaps & (1 << ic->ic_curmode))
781 			break;
782 	}
783 
784 	ieee80211_setmode(ic, ic->ic_curmode);
785 
786 	return (ic->ic_curmode);
787 }
788 
789 /*
790  * Return the phy mode for with the specified channel so the
791  * caller can select a rate set.  This is problematic and the
792  * work here assumes how things work elsewhere in this code.
793  *
794  * XXX never returns turbo modes -dcy
795  */
796 enum ieee80211_phymode
797 ieee80211_chan2mode(struct ieee80211com *ic,
798     const struct ieee80211_channel *chan)
799 {
800 	/*
801 	 * NB: this assumes the channel would not be supplied to us
802 	 *     unless it was already compatible with the current mode.
803 	 */
804 	if (ic->ic_curmode != IEEE80211_MODE_AUTO ||
805 	    chan == IEEE80211_CHAN_ANYC)
806 		return ic->ic_curmode;
807 	/*
808 	 * In autoselect mode; deduce a mode based on the channel
809 	 * characteristics.  We assume that turbo-only channels
810 	 * are not considered when the channel set is constructed.
811 	 */
812 	if (IEEE80211_IS_CHAN_T(chan))
813 		return IEEE80211_MODE_TURBO;
814 	else if (IEEE80211_IS_CHAN_5GHZ(chan))
815 		return IEEE80211_MODE_11A;
816 	else if (chan->ic_flags & (IEEE80211_CHAN_OFDM|IEEE80211_CHAN_DYN))
817 		return IEEE80211_MODE_11G;
818 	else
819 		return IEEE80211_MODE_11B;
820 }
821 
822 /*
823  * convert IEEE80211 rate value to ifmedia subtype.
824  * ieee80211 rate is in unit of 0.5Mbps.
825  */
826 int
827 ieee80211_rate2media(struct ieee80211com *ic, int rate,
828     enum ieee80211_phymode mode)
829 {
830 #define	N(a)	(sizeof(a) / sizeof(a[0]))
831 	static const struct {
832 		u_int	m;	/* rate + mode */
833 		u_int	r;	/* if_media rate */
834 	} rates[] = {
835 		{   2 | IFM_IEEE80211_11B, IFM_IEEE80211_DS1 },
836 		{   4 | IFM_IEEE80211_11B, IFM_IEEE80211_DS2 },
837 		{  11 | IFM_IEEE80211_11B, IFM_IEEE80211_DS5 },
838 		{  22 | IFM_IEEE80211_11B, IFM_IEEE80211_DS11 },
839 		{  44 | IFM_IEEE80211_11B, IFM_IEEE80211_DS22 },
840 		{  12 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM6 },
841 		{  18 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM9 },
842 		{  24 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM12 },
843 		{  36 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM18 },
844 		{  48 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM24 },
845 		{  72 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM36 },
846 		{  96 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM48 },
847 		{ 108 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM54 },
848 		{   2 | IFM_IEEE80211_11G, IFM_IEEE80211_DS1 },
849 		{   4 | IFM_IEEE80211_11G, IFM_IEEE80211_DS2 },
850 		{  11 | IFM_IEEE80211_11G, IFM_IEEE80211_DS5 },
851 		{  22 | IFM_IEEE80211_11G, IFM_IEEE80211_DS11 },
852 		{  12 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM6 },
853 		{  18 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM9 },
854 		{  24 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM12 },
855 		{  36 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM18 },
856 		{  48 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM24 },
857 		{  72 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM36 },
858 		{  96 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM48 },
859 		{ 108 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM54 },
860 		/* NB: OFDM72 doesn't really exist so we don't handle it */
861 	};
862 	u_int mask, i;
863 
864 	mask = rate & IEEE80211_RATE_VAL;
865 	switch (mode) {
866 	case IEEE80211_MODE_11A:
867 	case IEEE80211_MODE_TURBO:
868 		mask |= IFM_IEEE80211_11A;
869 		break;
870 	case IEEE80211_MODE_11B:
871 		mask |= IFM_IEEE80211_11B;
872 		break;
873 	case IEEE80211_MODE_AUTO:
874 		/* NB: hack, 11g matches both 11b+11a rates */
875 		/* FALLTHROUGH */
876 	case IEEE80211_MODE_11G:
877 		mask |= IFM_IEEE80211_11G;
878 		break;
879 	}
880 	for (i = 0; i < N(rates); i++)
881 		if (rates[i].m == mask)
882 			return rates[i].r;
883 	return IFM_AUTO;
884 #undef N
885 }
886 
887 int
888 ieee80211_media2rate(int mword)
889 {
890 #define	N(a)	(sizeof(a) / sizeof(a[0]))
891 	int i;
892 	static const struct {
893 		int subtype;
894 		int rate;
895 	} ieeerates[] = {
896 		{ IFM_AUTO,		-1	},
897 		{ IFM_MANUAL,		0	},
898 		{ IFM_NONE,		0	},
899 		{ IFM_IEEE80211_DS1,	2	},
900 		{ IFM_IEEE80211_DS2,	4	},
901 		{ IFM_IEEE80211_DS5,	11	},
902 		{ IFM_IEEE80211_DS11,	22	},
903 		{ IFM_IEEE80211_DS22,	44	},
904 		{ IFM_IEEE80211_OFDM6,	12	},
905 		{ IFM_IEEE80211_OFDM9,	18	},
906 		{ IFM_IEEE80211_OFDM12,	24	},
907 		{ IFM_IEEE80211_OFDM18,	36	},
908 		{ IFM_IEEE80211_OFDM24,	48	},
909 		{ IFM_IEEE80211_OFDM36,	72	},
910 		{ IFM_IEEE80211_OFDM48,	96	},
911 		{ IFM_IEEE80211_OFDM54,	108	},
912 		{ IFM_IEEE80211_OFDM72,	144	},
913 	};
914 	for (i = 0; i < N(ieeerates); i++) {
915 		if (ieeerates[i].subtype == IFM_SUBTYPE(mword))
916 			return ieeerates[i].rate;
917 	}
918 	return 0;
919 #undef N
920 }
921 
922 /*
923  * Convert bit rate (in 0.5Mbps units) to PLCP signal (R4-R1) and vice versa.
924  */
925 u_int8_t
926 ieee80211_rate2plcp(u_int8_t rate, enum ieee80211_phymode mode)
927 {
928 	rate &= IEEE80211_RATE_VAL;
929 
930 	if (mode == IEEE80211_MODE_11B) {
931 		/* IEEE Std 802.11b-1999 page 15, subclause 18.2.3.3 */
932 		switch (rate) {
933 		case 2:		return 10;
934 		case 4:		return 20;
935 		case 11:	return 55;
936 		case 22:	return 110;
937 		/* IEEE Std 802.11g-2003 page 19, subclause 19.3.2.1 */
938 		case 44:	return 220;
939 		}
940 	} else if (mode == IEEE80211_MODE_11G || mode == IEEE80211_MODE_11A) {
941 		/* IEEE Std 802.11a-1999 page 14, subclause 17.3.4.1 */
942 		switch (rate) {
943 		case 12:	return 0x0b;
944 		case 18:	return 0x0f;
945 		case 24:	return 0x0a;
946 		case 36:	return 0x0e;
947 		case 48:	return 0x09;
948 		case 72:	return 0x0d;
949 		case 96:	return 0x08;
950 		case 108:	return 0x0c;
951 		}
952         } else
953 		panic("Unexpected mode %u", mode);
954 
955 	DPRINTF(("unsupported rate %u\n", rate));
956 
957 	return 0;
958 }
959 
960 u_int8_t
961 ieee80211_plcp2rate(u_int8_t plcp, enum ieee80211_phymode mode)
962 {
963 	if (mode == IEEE80211_MODE_11B) {
964 		/* IEEE Std 802.11g-2003 page 19, subclause 19.3.2.1 */
965 		switch (plcp) {
966 		case 10:	return 2;
967 		case 20:	return 4;
968 		case 55:	return 11;
969 		case 110:	return 22;
970 		/* IEEE Std 802.11g-2003 page 19, subclause 19.3.2.1 */
971 		case 220:	return 44;
972 		}
973 	} else if (mode == IEEE80211_MODE_11G || mode == IEEE80211_MODE_11A) {
974 		/* IEEE Std 802.11a-1999 page 14, subclause 17.3.4.1 */
975 		switch (plcp) {
976 		case 0x0b:	return 12;
977 		case 0x0f:	return 18;
978 		case 0x0a:	return 24;
979 		case 0x0e:	return 36;
980 		case 0x09:	return 48;
981 		case 0x0d:	return 72;
982 		case 0x08:	return 96;
983 		case 0x0c:	return 108;
984 		}
985 	} else
986 		panic("unexpected mode %u", mode);
987 
988 	DPRINTF(("unsupported plcp %u\n", plcp));
989 
990 	return 0;
991 }
992