1 /*        $NetBSD: ieee80211.c,v 1.61 2021/08/21 11:55:25 andvar 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.c,v 1.22 2005/08/10 16:22:29 sam Exp $");
37 #endif
38 #ifdef __NetBSD__
39 __KERNEL_RCSID(0, "$NetBSD: ieee80211.c,v 1.61 2021/08/21 11:55:25 andvar Exp $");
40 #endif
41 
42 /*
43  * IEEE 802.11 generic handler
44  */
45 
46 #ifdef _KERNEL_OPT
47 #include "opt_inet.h"
48 #endif
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/kernel.h>
53 
54 #include <sys/socket.h>
55 #include <sys/sockio.h>
56 #include <sys/endian.h>
57 #include <sys/errno.h>
58 #include <sys/proc.h>
59 #include <sys/sysctl.h>
60 
61 #include <net/if.h>
62 #include <net/if_media.h>
63 #include <net/if_arp.h>
64 #include <net/if_ether.h>
65 #include <net/if_llc.h>
66 
67 #include <net80211/ieee80211_netbsd.h>
68 #include <net80211/ieee80211_var.h>
69 #include <net80211/ieee80211_sysctl.h>
70 
71 #include <net/bpf.h>
72 
73 #ifdef INET
74 #include <netinet/in.h>
75 #include <net/if_ether.h>
76 #endif
77 
78 const struct ieee80211_channel ieee80211_channel_anyc = {
79           0, 0
80 };
81 
82 struct ieee80211com_head ieee80211com_head =
83     LIST_HEAD_INITIALIZER(ieee80211com_head);
84 
85 const char *ieee80211_phymode_name[] = {
86           "auto",             /* IEEE80211_MODE_AUTO */
87           "11a",              /* IEEE80211_MODE_11A */
88           "11b",              /* IEEE80211_MODE_11B */
89           "11g",              /* IEEE80211_MODE_11G */
90           "FH",               /* IEEE80211_MODE_FH */
91           "turboA", /* IEEE80211_MODE_TURBO_A */
92           "turboG", /* IEEE80211_MODE_TURBO_G */
93 };
94 
95 /* list of all instances */
96 SLIST_HEAD(ieee80211_list, ieee80211com);
97 static struct ieee80211_list ieee80211_list =
98           SLIST_HEAD_INITIALIZER(ieee80211_list);
99 static u_int8_t ieee80211_vapmap[32];             /* enough for 256 */
100 
101 static void
ieee80211_add_vap(struct ieee80211com * ic)102 ieee80211_add_vap(struct ieee80211com *ic)
103 {
104 #define   N(a)      (sizeof(a)/sizeof(a[0]))
105           int i;
106           int s;
107           u_int8_t b;
108 
109           s = splnet();
110           ic->ic_vap = 0;
111           for (i = 0; i < N(ieee80211_vapmap) && ieee80211_vapmap[i] == 0xff; i++)
112                     ic->ic_vap += NBBY;
113           if (i == N(ieee80211_vapmap))
114                     panic("vap table full");
115           for (b = ieee80211_vapmap[i]; b & 1; b >>= 1)
116                     ic->ic_vap++;
117           setbit(ieee80211_vapmap, ic->ic_vap);
118           SLIST_INSERT_HEAD(&ieee80211_list, ic, ic_next);
119           splx(s);
120 #undef N
121 }
122 
123 static void
ieee80211_remove_vap(struct ieee80211com * ic)124 ieee80211_remove_vap(struct ieee80211com *ic)
125 {
126           int s;
127 
128           s = splnet();
129           SLIST_REMOVE(&ieee80211_list, ic, ieee80211com, ic_next);
130           IASSERT(ic->ic_vap < sizeof(ieee80211_vapmap)*NBBY,
131                     ("invalid vap id %d", ic->ic_vap));
132           IASSERT(isset(ieee80211_vapmap, ic->ic_vap),
133                     ("vap id %d not allocated", ic->ic_vap));
134           clrbit(ieee80211_vapmap, ic->ic_vap);
135           splx(s);
136 }
137 
138 /*
139  * Default reset method for use with the ioctl support.  This
140  * method is invoked after any state change in the 802.11
141  * layer that should be propagated to the hardware but not
142  * require re-initialization of the 802.11 state machine (e.g
143  * rescanning for an ap).  We always return ENETRESET which
144  * should cause the driver to re-initialize the device. Drivers
145  * can override this method to implement more optimized support.
146  */
147 static int
ieee80211_default_reset(struct ifnet * ifp)148 ieee80211_default_reset(struct ifnet *ifp)
149 {
150           return ENETRESET;
151 }
152 
153 static void
ieee80211_init_link_state(struct ieee80211com * ic)154 ieee80211_init_link_state(struct ieee80211com *ic)
155 {
156           struct ifnet *ifp = ic->ic_ifp;
157 
158           /*
159            * Link state does not make sense in IBSS or HOSTAP modes.
160            * We know that the link in MONITOR mode is DOWN as we cannot
161            * transmit, only monitor.
162            * That leaves BSS mode, which starts off DOWN and will
163            * transition to UP when it joins a node.
164            */
165           switch (ic->ic_opmode) {
166           case IEEE80211_M_AHDEMO:
167           case IEEE80211_M_HOSTAP:
168           case IEEE80211_M_IBSS:
169                     if_link_state_change(ifp, LINK_STATE_UNKNOWN);
170                     break;
171           default:
172                     if_link_state_change(ifp, LINK_STATE_DOWN);
173                     break;
174           }
175 }
176 
177 void
ieee80211_ifattach(struct ieee80211com * ic)178 ieee80211_ifattach(struct ieee80211com *ic)
179 {
180           struct ifnet *ifp = ic->ic_ifp;
181           struct ieee80211_channel *c;
182           int i;
183 
184 #ifdef __NetBSD__
185           ieee80211_init();
186 #endif /* __NetBSD__ */
187 
188           ether_ifattach(ifp, ic->ic_myaddr);
189           bpf_attach2(ifp, DLT_IEEE802_11,
190               sizeof(struct ieee80211_frame_addr4), &ic->ic_rawbpf);
191 
192           ieee80211_crypto_attach(ic);
193 
194           /*
195            * Fill in 802.11 available channel set, mark
196            * all available channels as active, and pick
197            * a default channel if not already specified.
198            */
199           memset(ic->ic_chan_avail, 0, sizeof(ic->ic_chan_avail));
200           ic->ic_modecaps |= 1<<IEEE80211_MODE_AUTO;
201           for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
202                     c = &ic->ic_channels[i];
203                     if (c->ic_flags) {
204                               /*
205                                * Verify driver passed us valid data.
206                                */
207                               if (i != ieee80211_chan2ieee(ic, c)) {
208                                         if_printf(ifp, "bad channel ignored; "
209                                                   "freq %u flags %x number %u\n",
210                                                   c->ic_freq, c->ic_flags, i);
211                                         c->ic_flags = 0;    /* NB: remove */
212                                         continue;
213                               }
214                               setbit(ic->ic_chan_avail, i);
215                               /*
216                                * Identify mode capabilities.
217                                */
218                               if (IEEE80211_IS_CHAN_A(c))
219                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_11A;
220                               if (IEEE80211_IS_CHAN_B(c))
221                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_11B;
222                               if (IEEE80211_IS_CHAN_PUREG(c))
223                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_11G;
224                               if (IEEE80211_IS_CHAN_FHSS(c))
225                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_FH;
226                               if (IEEE80211_IS_CHAN_T(c))
227                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_TURBO_A;
228                               if (IEEE80211_IS_CHAN_108G(c))
229                                         ic->ic_modecaps |= 1<<IEEE80211_MODE_TURBO_G;
230                               if (ic->ic_curchan == NULL) {
231                                         /* arbitrarily pick the first channel */
232                                         ic->ic_curchan = &ic->ic_channels[i];
233                               }
234                     }
235           }
236           /* validate ic->ic_curmode */
237           if ((ic->ic_modecaps & (1<<ic->ic_curmode)) == 0)
238                     ic->ic_curmode = IEEE80211_MODE_AUTO;
239           ic->ic_des_chan = IEEE80211_CHAN_ANYC;  /* any channel is ok */
240 #if 0
241           /*
242            * Enable WME by default if we're capable.
243            */
244           if (ic->ic_caps & IEEE80211_C_WME)
245                     ic->ic_flags |= IEEE80211_F_WME;
246 #endif
247           (void) ieee80211_setmode(ic, ic->ic_curmode);
248 
249           if (ic->ic_bintval == 0)
250                     ic->ic_bintval = IEEE80211_BINTVAL_DEFAULT;
251           ic->ic_bmisstimeout = 7*ic->ic_bintval; /* default 7 beacons */
252           ic->ic_dtim_period = IEEE80211_DTIM_DEFAULT;
253           IEEE80211_BEACON_LOCK_INIT(ic, "beacon");
254 
255           if (ic->ic_lintval == 0)
256                     ic->ic_lintval = ic->ic_bintval;
257           ic->ic_txpowlimit = IEEE80211_TXPOWER_MAX;
258 
259           LIST_INSERT_HEAD(&ieee80211com_head, ic, ic_list);
260           ieee80211_node_attach(ic);
261           ieee80211_proto_attach(ic);
262 
263           ieee80211_add_vap(ic);
264 
265           ieee80211_sysctl_attach(ic);            /* NB: requires ic_vap */
266 
267           /*
268            * Install a default reset method for the ioctl support.
269            * The driver is expected to fill this in before calling us.
270            */
271           if (ic->ic_reset == NULL)
272                     ic->ic_reset = ieee80211_default_reset;
273 
274           ieee80211_init_link_state(ic);
275 }
276 
277 void
ieee80211_ifdetach(struct ieee80211com * ic)278 ieee80211_ifdetach(struct ieee80211com *ic)
279 {
280           struct ifnet *ifp = ic->ic_ifp;
281 
282           ieee80211_remove_vap(ic);
283 
284           ieee80211_sysctl_detach(ic);
285           ieee80211_proto_detach(ic);
286           ieee80211_crypto_detach(ic);
287           ieee80211_node_detach(ic);
288           LIST_REMOVE(ic, ic_list);
289           ifmedia_fini(&ic->ic_media);
290 
291           IEEE80211_BEACON_LOCK_DESTROY(ic);
292 
293           bpf_detach(ifp);
294           ether_ifdetach(ifp);
295 }
296 
297 /*
298  * Convert MHz frequency to IEEE channel number.
299  */
300 u_int
ieee80211_mhz2ieee(u_int freq,u_int flags)301 ieee80211_mhz2ieee(u_int freq, u_int flags)
302 {
303           if (flags & IEEE80211_CHAN_2GHZ) {      /* 2GHz band */
304                     if (freq == 2484)
305                               return 14;
306                     if (freq < 2484)
307                               return (freq - 2407) / 5;
308                     else
309                               return 15 + ((freq - 2512) / 20);
310           } else if (flags & IEEE80211_CHAN_5GHZ) {         /* 5 GHz band */
311                     return (freq - 5000) / 5;
312           } else {                                /* either, guess */
313                     if (freq == 2484)
314                               return 14;
315                     if (freq < 2484)
316                               return (freq - 2407) / 5;
317                     if (freq < 5000)
318                               return 15 + ((freq - 2512) / 20);
319                     return (freq - 5000) / 5;
320           }
321 }
322 
323 /*
324  * Convert channel to IEEE channel number.
325  */
326 u_int
ieee80211_chan2ieee(struct ieee80211com * ic,struct ieee80211_channel * c)327 ieee80211_chan2ieee(struct ieee80211com *ic, struct ieee80211_channel *c)
328 {
329           if (ic->ic_channels <= c && c <= &ic->ic_channels[IEEE80211_CHAN_MAX])
330                     return c - ic->ic_channels;
331           else if (c == IEEE80211_CHAN_ANYC)
332                     return IEEE80211_CHAN_ANY;
333           else if (c != NULL) {
334                     if_printf(ic->ic_ifp, "invalid channel freq %u flags %x\n",
335                               c->ic_freq, c->ic_flags);
336                     return 0;           /* XXX */
337           } else {
338                     if_printf(ic->ic_ifp, "invalid channel (NULL)\n");
339                     return 0;           /* XXX */
340           }
341 }
342 
343 /*
344  * Convert IEEE channel number to MHz frequency.
345  */
346 u_int
ieee80211_ieee2mhz(u_int chan,u_int flags)347 ieee80211_ieee2mhz(u_int chan, u_int flags)
348 {
349           if (flags & IEEE80211_CHAN_2GHZ) {      /* 2GHz band */
350                     if (chan == 14)
351                               return 2484;
352                     if (chan < 14)
353                               return 2407 + chan*5;
354                     else
355                               return 2512 + ((chan-15)*20);
356           } else if (flags & IEEE80211_CHAN_5GHZ) {/* 5 GHz band */
357                     return 5000 + (chan*5);
358           } else {                                /* either, guess */
359                     if (chan == 14)
360                               return 2484;
361                     if (chan < 14)                          /* 0-13 */
362                               return 2407 + chan*5;
363                     if (chan < 27)                          /* 15-26 */
364                               return 2512 + ((chan-15)*20);
365                     return 5000 + (chan*5);
366           }
367 }
368 
369 /*
370  * Setup the media data structures according to the channel and
371  * rate tables.  This must be called by the driver after
372  * ieee80211_attach and before most anything else.
373  */
374 void
ieee80211_media_init_with_lock(struct ieee80211com * ic,ifm_change_cb_t media_change,ifm_stat_cb_t media_stat,ieee80211_media_lock_t * lock)375 ieee80211_media_init_with_lock(struct ieee80211com *ic,
376           ifm_change_cb_t media_change, ifm_stat_cb_t media_stat,
377           ieee80211_media_lock_t *lock)
378 {
379 #define   ADD(_ic, _s, _o) \
380           ifmedia_add(&(_ic)->ic_media, \
381                     IFM_MAKEWORD(IFM_IEEE80211, (_s), (_o), 0), 0, NULL)
382           struct ifnet *ifp = ic->ic_ifp;
383           struct ifmediareq imr;
384           int i, j, mode, rate, maxrate, mword, mopt, r;
385           const struct ieee80211_rateset *rs;
386           struct ieee80211_rateset allrates;
387 
388           /*
389            * Do late attach work that must wait for any subclass
390            * (i.e. driver) work such as overriding methods.
391            */
392           ieee80211_node_lateattach(ic);
393 
394 #ifdef IEEE80211_NO_HOSTAP
395           ic->ic_caps &= ~IEEE80211_C_HOSTAP;
396 #endif /* IEEE80211_NO_HOSTAP */
397 
398           /*
399            * Fill in media characteristics.
400            */
401           ifmedia_init_with_lock(&ic->ic_media, 0,
402               media_change, media_stat, lock);
403           maxrate = 0;
404           memset(&allrates, 0, sizeof(allrates));
405           for (mode = IEEE80211_MODE_AUTO; mode < IEEE80211_MODE_MAX; mode++) {
406                     static const u_int mopts[] = {
407                               IFM_AUTO,
408                               IFM_IEEE80211_11A,
409                               IFM_IEEE80211_11B,
410                               IFM_IEEE80211_11G,
411                               IFM_IEEE80211_FH,
412                               IFM_IEEE80211_11A | IFM_IEEE80211_TURBO,
413                               IFM_IEEE80211_11G | IFM_IEEE80211_TURBO,
414                     };
415                     if ((ic->ic_modecaps & (1<<mode)) == 0)
416                               continue;
417                     mopt = mopts[mode];
418                     ADD(ic, IFM_AUTO, mopt);      /* e.g. 11a auto */
419                     if (ic->ic_caps & IEEE80211_C_IBSS)
420                               ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_ADHOC);
421                     if (ic->ic_caps & IEEE80211_C_HOSTAP)
422                               ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_HOSTAP);
423                     if (ic->ic_caps & IEEE80211_C_AHDEMO)
424                               ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_ADHOC | IFM_FLAG0);
425                     if (ic->ic_caps & IEEE80211_C_MONITOR)
426                               ADD(ic, IFM_AUTO, mopt | IFM_IEEE80211_MONITOR);
427                     if (mode == IEEE80211_MODE_AUTO)
428                               continue;
429                     rs = &ic->ic_sup_rates[mode];
430                     for (i = 0; i < rs->rs_nrates; i++) {
431                               rate = rs->rs_rates[i];
432                               mword = ieee80211_rate2media(ic, rate, mode);
433                               if (mword == 0)
434                                         continue;
435                               ADD(ic, mword, mopt);
436                               if (ic->ic_caps & IEEE80211_C_IBSS)
437                                         ADD(ic, mword, mopt | IFM_IEEE80211_ADHOC);
438                               if (ic->ic_caps & IEEE80211_C_HOSTAP)
439                                         ADD(ic, mword, mopt | IFM_IEEE80211_HOSTAP);
440                               if (ic->ic_caps & IEEE80211_C_AHDEMO)
441                                         ADD(ic, mword, mopt | IFM_IEEE80211_ADHOC | IFM_FLAG0);
442                               if (ic->ic_caps & IEEE80211_C_MONITOR)
443                                         ADD(ic, mword, mopt | IFM_IEEE80211_MONITOR);
444                               /*
445                                * Add rate to the collection of all rates.
446                                */
447                               r = rate & IEEE80211_RATE_VAL;
448                               for (j = 0; j < allrates.rs_nrates; j++)
449                                         if (allrates.rs_rates[j] == r)
450                                                   break;
451                               if (j == allrates.rs_nrates) {
452                                         /* unique, add to the set */
453                                         allrates.rs_rates[j] = r;
454                                         allrates.rs_nrates++;
455                               }
456                               rate = (rate & IEEE80211_RATE_VAL) / 2;
457                               if (rate > maxrate)
458                                         maxrate = rate;
459                     }
460           }
461           for (i = 0; i < allrates.rs_nrates; i++) {
462                     mword = ieee80211_rate2media(ic, allrates.rs_rates[i],
463                                         IEEE80211_MODE_AUTO);
464                     if (mword == 0)
465                               continue;
466                     mword = IFM_SUBTYPE(mword);   /* remove media options */
467                     ADD(ic, mword, 0);
468                     if (ic->ic_caps & IEEE80211_C_IBSS)
469                               ADD(ic, mword, IFM_IEEE80211_ADHOC);
470                     if (ic->ic_caps & IEEE80211_C_HOSTAP)
471                               ADD(ic, mword, IFM_IEEE80211_HOSTAP);
472                     if (ic->ic_caps & IEEE80211_C_AHDEMO)
473                               ADD(ic, mword, IFM_IEEE80211_ADHOC | IFM_FLAG0);
474                     if (ic->ic_caps & IEEE80211_C_MONITOR)
475                               ADD(ic, mword, IFM_IEEE80211_MONITOR);
476           }
477           ieee80211_media_status(ifp, &imr);
478           ifmedia_set(&ic->ic_media, imr.ifm_active);
479 
480           if (maxrate)
481                     ifp->if_baudrate = IF_Mbps(maxrate);
482 #undef ADD
483 }
484 
485 void
ieee80211_media_init(struct ieee80211com * ic,ifm_change_cb_t media_change,ifm_stat_cb_t media_stat)486 ieee80211_media_init(struct ieee80211com *ic,
487           ifm_change_cb_t media_change, ifm_stat_cb_t media_stat)
488 {
489 
490           ieee80211_media_init_with_lock(ic, media_change, media_stat, NULL);
491 }
492 
493 void
ieee80211_announce(struct ieee80211com * ic)494 ieee80211_announce(struct ieee80211com *ic)
495 {
496           struct ifnet *ifp = ic->ic_ifp;
497           int i, mode, rate, mword;
498           struct ieee80211_rateset *rs;
499 
500           for (mode = IEEE80211_MODE_11A; mode < IEEE80211_MODE_MAX; mode++) {
501                     if ((ic->ic_modecaps & (1<<mode)) == 0)
502                               continue;
503                     aprint_debug("%s: %s rates: ", ifp->if_xname,
504                         ieee80211_phymode_name[mode]);
505                     rs = &ic->ic_sup_rates[mode];
506                     for (i = 0; i < rs->rs_nrates; i++) {
507                               rate = rs->rs_rates[i];
508                               mword = ieee80211_rate2media(ic, rate, mode);
509                               if (mword == 0)
510                                         continue;
511                               aprint_debug("%s%d%sMbps", (i != 0 ? " " : ""),
512                                   (rate & IEEE80211_RATE_VAL) / 2,
513                                   ((rate & 0x1) != 0 ? ".5" : ""));
514                     }
515                     aprint_debug("\n");
516           }
517 }
518 
519 static int
findrate(struct ieee80211com * ic,enum ieee80211_phymode mode,int rate)520 findrate(struct ieee80211com *ic, enum ieee80211_phymode mode, int rate)
521 {
522 #define   IEEERATE(_ic,_m,_i) \
523           ((_ic)->ic_sup_rates[_m].rs_rates[_i] & IEEE80211_RATE_VAL)
524           int i, nrates = ic->ic_sup_rates[mode].rs_nrates;
525           for (i = 0; i < nrates; i++)
526                     if (IEEERATE(ic, mode, i) == rate)
527                               return i;
528           return -1;
529 #undef IEEERATE
530 }
531 
532 /*
533  * Find an instance by its mac address.
534  */
535 struct ieee80211com *
ieee80211_find_vap(const u_int8_t mac[IEEE80211_ADDR_LEN])536 ieee80211_find_vap(const u_int8_t mac[IEEE80211_ADDR_LEN])
537 {
538           int s;
539           struct ieee80211com *ic;
540 
541           s = splnet();
542           SLIST_FOREACH(ic, &ieee80211_list, ic_next)
543                     if (IEEE80211_ADDR_EQ(mac, ic->ic_myaddr))
544                               break;
545           splx(s);
546           return ic;
547 }
548 
549 static struct ieee80211com *
ieee80211_find_instance(struct ifnet * ifp)550 ieee80211_find_instance(struct ifnet *ifp)
551 {
552           int s;
553           struct ieee80211com *ic;
554 
555           s = splnet();
556           /* XXX not right for multiple instances but works for now */
557           SLIST_FOREACH(ic, &ieee80211_list, ic_next)
558                     if (ic->ic_ifp == ifp)
559                               break;
560           splx(s);
561           return ic;
562 }
563 
564 /*
565  * Handle a media change request.
566  */
567 int
ieee80211_media_change(struct ifnet * ifp)568 ieee80211_media_change(struct ifnet *ifp)
569 {
570           struct ieee80211com *ic;
571           struct ifmedia_entry *ime;
572           enum ieee80211_opmode newopmode;
573           enum ieee80211_phymode newphymode;
574           int i, j, newrate, error = 0;
575 
576           ic = ieee80211_find_instance(ifp);
577           if (!ic) {
578                     if_printf(ifp, "%s: no 802.11 instance!\n", __func__);
579                     return EINVAL;
580           }
581           ime = ic->ic_media.ifm_cur;
582           /*
583            * First, identify the phy mode.
584            */
585           switch (IFM_MODE(ime->ifm_media)) {
586           case IFM_IEEE80211_11A:
587                     newphymode = IEEE80211_MODE_11A;
588                     break;
589           case IFM_IEEE80211_11B:
590                     newphymode = IEEE80211_MODE_11B;
591                     break;
592           case IFM_IEEE80211_11G:
593                     newphymode = IEEE80211_MODE_11G;
594                     break;
595           case IFM_IEEE80211_FH:
596                     newphymode = IEEE80211_MODE_FH;
597                     break;
598           case IFM_AUTO:
599                     newphymode = IEEE80211_MODE_AUTO;
600                     break;
601           default:
602                     return EINVAL;
603           }
604           /*
605            * Turbo mode is an ``option''.
606            * XXX does not apply to AUTO
607            */
608           if (ime->ifm_media & IFM_IEEE80211_TURBO) {
609                     if (newphymode == IEEE80211_MODE_11A)
610                               newphymode = IEEE80211_MODE_TURBO_A;
611                     else if (newphymode == IEEE80211_MODE_11G)
612                               newphymode = IEEE80211_MODE_TURBO_G;
613                     else
614                               return EINVAL;
615           }
616           /*
617            * Validate requested mode is available.
618            */
619           if ((ic->ic_modecaps & (1<<newphymode)) == 0)
620                     return EINVAL;
621 
622           /*
623            * Next, the fixed/variable rate.
624            */
625           i = -1;
626           if (IFM_SUBTYPE(ime->ifm_media) != IFM_AUTO) {
627                     /*
628                      * Convert media subtype to rate.
629                      */
630                     newrate = ieee80211_media2rate(ime->ifm_media);
631                     if (newrate == 0)
632                               return EINVAL;
633                     /*
634                      * Check the rate table for the specified/current phy.
635                      */
636                     if (newphymode == IEEE80211_MODE_AUTO) {
637                               /*
638                                * In autoselect mode search for the rate.
639                                */
640                               for (j = IEEE80211_MODE_11A;
641                                    j < IEEE80211_MODE_MAX; j++) {
642                                         if ((ic->ic_modecaps & (1<<j)) == 0)
643                                                   continue;
644                                         i = findrate(ic, j, newrate);
645                                         if (i != -1) {
646                                                   /* lock mode too */
647                                                   newphymode = j;
648                                                   break;
649                                         }
650                               }
651                     } else {
652                               i = findrate(ic, newphymode, newrate);
653                     }
654                     if (i == -1)                            /* mode/rate mismatch */
655                               return EINVAL;
656           }
657           /* NB: defer rate setting to later */
658 
659           /*
660            * Deduce new operating mode but don't install it just yet.
661            */
662           if ((ime->ifm_media & (IFM_IEEE80211_ADHOC|IFM_FLAG0)) ==
663               (IFM_IEEE80211_ADHOC|IFM_FLAG0))
664                     newopmode = IEEE80211_M_AHDEMO;
665           else if (ime->ifm_media & IFM_IEEE80211_HOSTAP)
666                     newopmode = IEEE80211_M_HOSTAP;
667           else if (ime->ifm_media & IFM_IEEE80211_ADHOC)
668                     newopmode = IEEE80211_M_IBSS;
669           else if (ime->ifm_media & IFM_IEEE80211_MONITOR)
670                     newopmode = IEEE80211_M_MONITOR;
671           else
672                     newopmode = IEEE80211_M_STA;
673 
674 #ifndef IEEE80211_NO_HOSTAP
675           /*
676            * Autoselect doesn't make sense when operating as an AP.
677            * If no phy mode has been selected, pick one and lock it
678            * down so rate tables can be used in forming beacon frames
679            * and the like.
680            */
681           if (newopmode == IEEE80211_M_HOSTAP &&
682               newphymode == IEEE80211_MODE_AUTO) {
683                     for (j = IEEE80211_MODE_11A; j < IEEE80211_MODE_MAX; j++)
684                               if (ic->ic_modecaps & (1<<j)) {
685                                         newphymode = j;
686                                         break;
687                               }
688           }
689 #endif /* !IEEE80211_NO_HOSTAP */
690 
691           /*
692            * Handle phy mode change.
693            */
694           if (ic->ic_curmode != newphymode) {               /* change phy mode */
695                     error = ieee80211_setmode(ic, newphymode);
696                     if (error != 0)
697                               return error;
698                     error = ENETRESET;
699           }
700 
701           /*
702            * Committed to changes, install the rate setting.
703            */
704           if (ic->ic_fixed_rate != i) {
705                     ic->ic_fixed_rate = i;                            /* set fixed tx rate */
706                     error = ENETRESET;
707           }
708 
709           /*
710            * Handle operating mode change.
711            */
712           if (ic->ic_opmode != newopmode) {
713                     ic->ic_opmode = newopmode;
714                     switch (newopmode) {
715                     case IEEE80211_M_AHDEMO:
716                     case IEEE80211_M_HOSTAP:
717                     case IEEE80211_M_STA:
718                     case IEEE80211_M_MONITOR:
719                               ic->ic_flags &= ~IEEE80211_F_IBSSON;
720                               break;
721                     case IEEE80211_M_IBSS:
722                               ic->ic_flags |= IEEE80211_F_IBSSON;
723                               break;
724                     }
725                     /*
726                      * Yech, slot time may change depending on the
727                      * operating mode so reset it to be sure everything
728                      * is setup appropriately.
729                      */
730                     ieee80211_reset_erp(ic);
731                     ieee80211_wme_initparams(ic); /* after opmode change */
732                     ieee80211_init_link_state(ic);          /* after opmode change */
733                     error = ENETRESET;
734           }
735 #ifdef notdef
736           if (error == 0)
737                     ifp->if_baudrate = ifmedia_baudrate(ime->ifm_media);
738 #endif
739           return error;
740 }
741 
742 void
ieee80211_media_status(struct ifnet * ifp,struct ifmediareq * imr)743 ieee80211_media_status(struct ifnet *ifp, struct ifmediareq *imr)
744 {
745           struct ieee80211com *ic;
746           struct ieee80211_rateset *rs;
747 
748           ic = ieee80211_find_instance(ifp);
749           if (!ic) {
750                     if_printf(ifp, "%s: no 802.11 instance!\n", __func__);
751                     return;
752           }
753           imr->ifm_status = IFM_AVALID;
754           imr->ifm_active = IFM_IEEE80211;
755           if (ic->ic_state == IEEE80211_S_RUN)
756                     imr->ifm_status |= IFM_ACTIVE;
757           /*
758            * Calculate a current rate if possible.
759            */
760           if (ic->ic_fixed_rate != IEEE80211_FIXED_RATE_NONE) {
761                     /*
762                      * A fixed rate is set, report that.
763                      */
764                     rs = &ic->ic_sup_rates[ic->ic_curmode];
765                     imr->ifm_active |= ieee80211_rate2media(ic,
766                               rs->rs_rates[ic->ic_fixed_rate], ic->ic_curmode);
767           } else if (ic->ic_opmode == IEEE80211_M_STA) {
768                     /*
769                      * In station mode report the current transmit rate.
770                      */
771                     rs = &ic->ic_bss->ni_rates;
772                     imr->ifm_active |= ieee80211_rate2media(ic,
773                               rs->rs_rates[ic->ic_bss->ni_txrate], ic->ic_curmode);
774           } else
775                     imr->ifm_active |= IFM_AUTO;
776           switch (ic->ic_opmode) {
777           case IEEE80211_M_STA:
778                     break;
779           case IEEE80211_M_IBSS:
780                     imr->ifm_active |= IFM_IEEE80211_ADHOC;
781                     break;
782           case IEEE80211_M_AHDEMO:
783                     /* should not come here */
784                     break;
785           case IEEE80211_M_HOSTAP:
786                     imr->ifm_active |= IFM_IEEE80211_HOSTAP;
787                     break;
788           case IEEE80211_M_MONITOR:
789                     imr->ifm_active |= IFM_IEEE80211_MONITOR;
790                     break;
791           }
792           switch (ic->ic_curmode) {
793           case IEEE80211_MODE_11A:
794                     imr->ifm_active |= IFM_IEEE80211_11A;
795                     break;
796           case IEEE80211_MODE_11B:
797                     imr->ifm_active |= IFM_IEEE80211_11B;
798                     break;
799           case IEEE80211_MODE_11G:
800                     imr->ifm_active |= IFM_IEEE80211_11G;
801                     break;
802           case IEEE80211_MODE_FH:
803                     imr->ifm_active |= IFM_IEEE80211_FH;
804                     break;
805           case IEEE80211_MODE_TURBO_A:
806                     imr->ifm_active |= IFM_IEEE80211_11A
807                                         |  IFM_IEEE80211_TURBO;
808                     break;
809           case IEEE80211_MODE_TURBO_G:
810                     imr->ifm_active |= IFM_IEEE80211_11G
811                                         |  IFM_IEEE80211_TURBO;
812                     break;
813           }
814 }
815 
816 void
ieee80211_watchdog(struct ieee80211com * ic)817 ieee80211_watchdog(struct ieee80211com *ic)
818 {
819           struct ieee80211_node_table *nt;
820           int need_inact_timer = 0;
821 
822           if (ic->ic_state != IEEE80211_S_INIT) {
823                     if (ic->ic_mgt_timer && --ic->ic_mgt_timer == 0)
824                               ieee80211_new_state(ic, IEEE80211_S_SCAN, 0);
825                     nt = &ic->ic_scan;
826                     if (nt->nt_inact_timer) {
827                               if (--nt->nt_inact_timer == 0)
828                                         nt->nt_timeout(nt);
829                               need_inact_timer += nt->nt_inact_timer;
830                     }
831                     nt = &ic->ic_sta;
832                     if (nt->nt_inact_timer) {
833                               if (--nt->nt_inact_timer == 0)
834                                         nt->nt_timeout(nt);
835                               need_inact_timer += nt->nt_inact_timer;
836                     }
837           }
838           if (ic->ic_mgt_timer != 0 || need_inact_timer)
839                     ic->ic_ifp->if_timer = 1;
840 }
841 
842 const struct ieee80211_rateset ieee80211_std_rateset_11a =
843           { 8, { 12, 18, 24, 36, 48, 72, 96, 108 } };
844 
845 const struct ieee80211_rateset ieee80211_std_rateset_11b =
846           { 4, { 2, 4, 11, 22 } };
847 
848 const struct ieee80211_rateset ieee80211_std_rateset_11g =
849           { 12, { 2, 4, 11, 22, 12, 18, 24, 36, 48, 72, 96, 108 } };
850 
851 /*
852  * Set the current phy mode and recalculate the active channel
853  * set based on the available channels for this mode.  Also
854  * select a new default/current channel if the current one is
855  * inappropriate for this mode.
856  */
857 int
ieee80211_setmode(struct ieee80211com * ic,enum ieee80211_phymode mode)858 ieee80211_setmode(struct ieee80211com *ic, enum ieee80211_phymode mode)
859 {
860 #define   N(a)      (sizeof(a) / sizeof(a[0]))
861           static const u_int chanflags[] = {
862                     0,                            /* IEEE80211_MODE_AUTO */
863                     IEEE80211_CHAN_A,   /* IEEE80211_MODE_11A */
864                     IEEE80211_CHAN_B,   /* IEEE80211_MODE_11B */
865                     IEEE80211_CHAN_PUREG,         /* IEEE80211_MODE_11G */
866                     IEEE80211_CHAN_FHSS,          /* IEEE80211_MODE_FH */
867                     IEEE80211_CHAN_T,   /* IEEE80211_MODE_TURBO_A */
868                     IEEE80211_CHAN_108G,          /* IEEE80211_MODE_TURBO_G */
869           };
870           struct ieee80211_channel *c;
871           u_int modeflags;
872           int i;
873 
874           /* validate new mode */
875           if ((ic->ic_modecaps & (1<<mode)) == 0) {
876                     IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
877                               "%s: mode %u not supported (caps 0x%x)\n",
878                               __func__, mode, ic->ic_modecaps);
879                     return EINVAL;
880           }
881 
882           /*
883            * Verify at least one channel is present in the available
884            * channel list before committing to the new mode.
885            */
886           IASSERT(mode < N(chanflags), ("Unexpected mode %u", mode));
887           modeflags = chanflags[mode];
888           for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
889                     c = &ic->ic_channels[i];
890                     if (c->ic_flags == 0)
891                               continue;
892                     if (mode == IEEE80211_MODE_AUTO) {
893                               /* ignore turbo channels for autoselect */
894                               if ((c->ic_flags & IEEE80211_CHAN_TURBO) == 0)
895                                         break;
896                     } else {
897                               if ((c->ic_flags & modeflags) == modeflags)
898                                         break;
899                     }
900           }
901           if (i > IEEE80211_CHAN_MAX) {
902                     IEEE80211_DPRINTF(ic, IEEE80211_MSG_ANY,
903                               "%s: no channels found for mode %u\n", __func__, mode);
904                     return EINVAL;
905           }
906 
907           /*
908            * Calculate the active channel set.
909            */
910           memset(ic->ic_chan_active, 0, sizeof(ic->ic_chan_active));
911           for (i = 0; i <= IEEE80211_CHAN_MAX; i++) {
912                     c = &ic->ic_channels[i];
913                     if (c->ic_flags == 0)
914                               continue;
915                     if (mode == IEEE80211_MODE_AUTO) {
916                               /* take anything but pure turbo channels */
917                               if ((c->ic_flags & IEEE80211_CHAN_TURBO) == 0)
918                                         setbit(ic->ic_chan_active, i);
919                     } else {
920                               if ((c->ic_flags & modeflags) == modeflags)
921                                         setbit(ic->ic_chan_active, i);
922                     }
923           }
924           /*
925            * If no current/default channel is setup or the current
926            * channel is wrong for the mode then pick the first
927            * available channel from the active list.  This is likely
928            * not the right one.
929            */
930           if (ic->ic_ibss_chan == NULL ||
931               isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ic->ic_ibss_chan))) {
932                     for (i = 0; i <= IEEE80211_CHAN_MAX; i++)
933                               if (isset(ic->ic_chan_active, i)) {
934                                         ic->ic_ibss_chan = &ic->ic_channels[i];
935                                         break;
936                               }
937                     IASSERT(ic->ic_ibss_chan != NULL &&
938                         isset(ic->ic_chan_active,
939                               ieee80211_chan2ieee(ic, ic->ic_ibss_chan)),
940                         ("Bad IBSS channel %u",
941                          ieee80211_chan2ieee(ic, ic->ic_ibss_chan)));
942           }
943           /*
944            * If the desired channel is set but no longer valid then reset it.
945            */
946           if (ic->ic_des_chan != IEEE80211_CHAN_ANYC &&
947               isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, ic->ic_des_chan)))
948                     ic->ic_des_chan = IEEE80211_CHAN_ANYC;
949 
950           /*
951            * Do mode-specific rate setup.
952            */
953           if (mode == IEEE80211_MODE_11G) {
954                     /*
955                      * Use a mixed 11b/11g rate set.
956                      */
957                     ieee80211_set11gbasicrates(&ic->ic_sup_rates[mode],
958                               IEEE80211_MODE_11G);
959           } else if (mode == IEEE80211_MODE_11B) {
960                     /*
961                      * Force pure 11b rate set.
962                      */
963                     ieee80211_set11gbasicrates(&ic->ic_sup_rates[mode],
964                               IEEE80211_MODE_11B);
965           }
966           /*
967            * Setup an initial rate set according to the
968            * current/default channel selected above.  This
969            * will be changed when scanning but must exist
970            * now so driver have a consistent state of ic_ibss_chan.
971            */
972           if (ic->ic_bss)               /* NB: can be called before lateattach */
973                     ic->ic_bss->ni_rates = ic->ic_sup_rates[mode];
974 
975           ic->ic_curmode = mode;
976           ieee80211_reset_erp(ic);      /* reset ERP state */
977           ieee80211_wme_initparams(ic); /* reset WME stat */
978 
979           return 0;
980 #undef N
981 }
982 
983 /*
984  * Return the phy mode for with the specified channel so the
985  * caller can select a rate set.  This is problematic for channels
986  * where multiple operating modes are possible (e.g. 11g+11b).
987  * In those cases we defer to the current operating mode when set.
988  */
989 enum ieee80211_phymode
ieee80211_chan2mode(struct ieee80211com * ic,struct ieee80211_channel * chan)990 ieee80211_chan2mode(struct ieee80211com *ic, struct ieee80211_channel *chan)
991 {
992           if (IEEE80211_IS_CHAN_T(chan)) {
993                     return IEEE80211_MODE_TURBO_A;
994           } else if (IEEE80211_IS_CHAN_5GHZ(chan)) {
995                     return IEEE80211_MODE_11A;
996           } else if (IEEE80211_IS_CHAN_FHSS(chan))
997                     return IEEE80211_MODE_FH;
998           else if (chan->ic_flags & (IEEE80211_CHAN_OFDM|IEEE80211_CHAN_DYN)) {
999                     /*
1000                      * This assumes all 11g channels are also usable
1001                      * for 11b, which is currently true.
1002                      */
1003                     if (ic->ic_curmode == IEEE80211_MODE_TURBO_G)
1004                               return IEEE80211_MODE_TURBO_G;
1005                     if (ic->ic_curmode == IEEE80211_MODE_11B)
1006                               return IEEE80211_MODE_11B;
1007                     return IEEE80211_MODE_11G;
1008           } else
1009                     return IEEE80211_MODE_11B;
1010 }
1011 
1012 /*
1013  * convert IEEE80211 rate value to ifmedia subtype.
1014  * ieee80211 rate is in unit of 0.5Mbps.
1015  */
1016 int
ieee80211_rate2media(struct ieee80211com * ic,int rate,enum ieee80211_phymode mode)1017 ieee80211_rate2media(struct ieee80211com *ic, int rate, enum ieee80211_phymode mode)
1018 {
1019 #define   N(a)      (sizeof(a) / sizeof(a[0]))
1020           static const struct {
1021                     u_int     m;        /* rate + mode */
1022                     u_int     r;        /* if_media rate */
1023           } rates[] = {
1024                     {   2 | IFM_IEEE80211_FH, IFM_IEEE80211_FH1 },
1025                     {   4 | IFM_IEEE80211_FH, IFM_IEEE80211_FH2 },
1026                     {   2 | IFM_IEEE80211_11B, IFM_IEEE80211_DS1 },
1027                     {   4 | IFM_IEEE80211_11B, IFM_IEEE80211_DS2 },
1028                     {  11 | IFM_IEEE80211_11B, IFM_IEEE80211_DS5 },
1029                     {  22 | IFM_IEEE80211_11B, IFM_IEEE80211_DS11 },
1030                     {  44 | IFM_IEEE80211_11B, IFM_IEEE80211_DS22 },
1031                     {  12 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM6 },
1032                     {  18 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM9 },
1033                     {  24 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM12 },
1034                     {  36 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM18 },
1035                     {  48 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM24 },
1036                     {  72 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM36 },
1037                     {  96 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM48 },
1038                     { 108 | IFM_IEEE80211_11A, IFM_IEEE80211_OFDM54 },
1039                     {   2 | IFM_IEEE80211_11G, IFM_IEEE80211_DS1 },
1040                     {   4 | IFM_IEEE80211_11G, IFM_IEEE80211_DS2 },
1041                     {  11 | IFM_IEEE80211_11G, IFM_IEEE80211_DS5 },
1042                     {  22 | IFM_IEEE80211_11G, IFM_IEEE80211_DS11 },
1043                     {  12 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM6 },
1044                     {  18 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM9 },
1045                     {  24 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM12 },
1046                     {  36 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM18 },
1047                     {  48 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM24 },
1048                     {  72 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM36 },
1049                     {  96 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM48 },
1050                     { 108 | IFM_IEEE80211_11G, IFM_IEEE80211_OFDM54 },
1051                     /* NB: OFDM72 doesn't really exist so we don't handle it */
1052           };
1053           u_int mask, i;
1054 
1055           mask = rate & IEEE80211_RATE_VAL;
1056           switch (mode) {
1057           case IEEE80211_MODE_11A:
1058           case IEEE80211_MODE_TURBO_A:
1059                     mask |= IFM_IEEE80211_11A;
1060                     break;
1061           case IEEE80211_MODE_11B:
1062                     mask |= IFM_IEEE80211_11B;
1063                     break;
1064           case IEEE80211_MODE_FH:
1065                     mask |= IFM_IEEE80211_FH;
1066                     break;
1067           case IEEE80211_MODE_AUTO:
1068                     /* NB: ic may be NULL for some drivers */
1069                     if (ic && ic->ic_phytype == IEEE80211_T_FH) {
1070                               mask |= IFM_IEEE80211_FH;
1071                               break;
1072                     }
1073                     /* NB: hack, 11g matches both 11b+11a rates */
1074                     /* fall thru... */
1075           case IEEE80211_MODE_11G:
1076           case IEEE80211_MODE_TURBO_G:
1077                     mask |= IFM_IEEE80211_11G;
1078                     break;
1079           }
1080           for (i = 0; i < N(rates); i++)
1081                     if (rates[i].m == mask)
1082                               return rates[i].r;
1083           return IFM_AUTO;
1084 #undef N
1085 }
1086 
1087 int
ieee80211_media2rate(int mword)1088 ieee80211_media2rate(int mword)
1089 {
1090 #define   N(a)      (sizeof(a) / sizeof(a[0]))
1091           static const int ieeerates[] = {
1092                     -1,                 /* IFM_AUTO */
1093                     0,                  /* IFM_MANUAL */
1094                     0,                  /* IFM_NONE */
1095                     2,                  /* IFM_IEEE80211_FH1 */
1096                     4,                  /* IFM_IEEE80211_FH2 */
1097                     4,                  /* IFM_IEEE80211_DS2 */
1098                     11,                 /* IFM_IEEE80211_DS5 */
1099                     22,                 /* IFM_IEEE80211_DS11 */
1100                     2,                  /* IFM_IEEE80211_DS1 */
1101                     44,                 /* IFM_IEEE80211_DS22 */
1102                     12,                 /* IFM_IEEE80211_OFDM6 */
1103                     18,                 /* IFM_IEEE80211_OFDM9 */
1104                     24,                 /* IFM_IEEE80211_OFDM12 */
1105                     36,                 /* IFM_IEEE80211_OFDM18 */
1106                     48,                 /* IFM_IEEE80211_OFDM24 */
1107                     72,                 /* IFM_IEEE80211_OFDM36 */
1108                     96,                 /* IFM_IEEE80211_OFDM48 */
1109                     108,                /* IFM_IEEE80211_OFDM54 */
1110                     144,                /* IFM_IEEE80211_OFDM72 */
1111           };
1112           return IFM_SUBTYPE(mword) < N(ieeerates) ?
1113                     ieeerates[IFM_SUBTYPE(mword)] : 0;
1114 #undef N
1115 }
1116