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ieee80211_proto.c revision 1.9
      1 /*	$NetBSD: ieee80211_proto.c,v 1.9 2004/07/16 02:38:34 dyoung Exp $	*/
      2 /*-
      3  * Copyright (c) 2001 Atsushi Onoe
      4  * Copyright (c) 2002, 2003 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_proto.c,v 1.8 2004/04/02 20:22:25 sam Exp $");
     37 #else
     38 __KERNEL_RCSID(0, "$NetBSD: ieee80211_proto.c,v 1.9 2004/07/16 02:38:34 dyoung Exp $");
     39 #endif
     40 
     41 /*
     42  * IEEE 802.11 protocol support.
     43  */
     44 
     45 #include "opt_inet.h"
     46 
     47 #include <sys/param.h>
     48 #include <sys/systm.h>
     49 #include <sys/mbuf.h>
     50 #include <sys/malloc.h>
     51 #include <sys/kernel.h>
     52 #include <sys/socket.h>
     53 #include <sys/sockio.h>
     54 #include <sys/endian.h>
     55 #include <sys/errno.h>
     56 #ifdef __FreeBSD__
     57 #include <sys/bus.h>
     58 #endif
     59 #include <sys/proc.h>
     60 #include <sys/sysctl.h>
     61 
     62 #ifdef __FreeBSD__
     63 #include <machine/atomic.h>
     64 #endif
     65 
     66 #include <net/if.h>
     67 #include <net/if_dl.h>
     68 #include <net/if_media.h>
     69 #include <net/if_arp.h>
     70 #ifdef __FreeBSD__
     71 #include <net/ethernet.h>
     72 #else
     73 #include <net/if_ether.h>
     74 #endif
     75 #include <net/if_llc.h>
     76 
     77 #include <net80211/ieee80211_var.h>
     78 #include <net80211/ieee80211_compat.h>
     79 
     80 #include <net/bpf.h>
     81 
     82 #ifdef INET
     83 #include <netinet/in.h>
     84 #ifdef __FreeBSD__
     85 #include <netinet/if_ether.h>
     86 #else
     87 #include <net/if_ether.h>
     88 #endif
     89 #endif
     90 
     91 #include <net/route.h>
     92 
     93 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
     94 
     95 const char *ieee80211_mgt_subtype_name[] = {
     96 	"assoc_req",	"assoc_resp",	"reassoc_req",	"reassoc_resp",
     97 	"probe_req",	"probe_resp",	"reserved#6",	"reserved#7",
     98 	"beacon",	"atim",		"disassoc",	"auth",
     99 	"deauth",	"reserved#13",	"reserved#14",	"reserved#15"
    100 };
    101 const char *ieee80211_state_name[IEEE80211_S_MAX] = {
    102 	"INIT",		/* IEEE80211_S_INIT */
    103 	"SCAN",		/* IEEE80211_S_SCAN */
    104 	"AUTH",		/* IEEE80211_S_AUTH */
    105 	"ASSOC",	/* IEEE80211_S_ASSOC */
    106 	"RUN"		/* IEEE80211_S_RUN */
    107 };
    108 
    109 static int ieee80211_newstate(struct ieee80211com *, enum ieee80211_state, int);
    110 
    111 void
    112 ieee80211_proto_attach(struct ifnet *ifp)
    113 {
    114 	struct ieee80211com *ic = (void *)ifp;
    115 
    116 	ifp->if_hdrlen = sizeof(struct ieee80211_frame);
    117 
    118 #ifdef notdef
    119 	ic->ic_rtsthreshold = IEEE80211_RTS_DEFAULT;
    120 #else
    121 	ic->ic_rtsthreshold = IEEE80211_RTS_MAX;
    122 #endif
    123 	ic->ic_fragthreshold = 2346;		/* XXX not used yet */
    124 	ic->ic_fixed_rate = -1;			/* no fixed rate */
    125 	ic->ic_protmode = IEEE80211_PROT_CTSONLY;
    126 
    127 #ifdef __FreeBSD__
    128 	mtx_init(&ic->ic_mgtq.ifq_mtx, ifp->if_xname, "mgmt send q", MTX_DEF);
    129 #endif
    130 
    131 	/* protocol state change handler */
    132 	ic->ic_newstate = ieee80211_newstate;
    133 
    134 	/* initialize management frame handlers */
    135 	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
    136 	ic->ic_send_mgmt = ieee80211_send_mgmt;
    137 }
    138 
    139 void
    140 ieee80211_proto_detach(struct ifnet *ifp)
    141 {
    142 	struct ieee80211com *ic = (void *)ifp;
    143 
    144 #ifdef __FreeBSD__
    145 	IF_DRAIN(&ic->ic_mgtq);
    146 	mtx_destroy(&ic->ic_mgtq.ifq_mtx);
    147 #else
    148 	IF_PURGE(&ic->ic_mgtq);
    149 	IF_PURGE(&ic->ic_pwrsaveq);
    150 #endif
    151 }
    152 
    153 void
    154 ieee80211_print_essid(u_int8_t *essid, int len)
    155 {
    156 	int i;
    157 	u_int8_t *p;
    158 
    159 	if (len > IEEE80211_NWID_LEN)
    160 		len = IEEE80211_NWID_LEN;
    161 	/* determine printable or not */
    162 	for (i = 0, p = essid; i < len; i++, p++) {
    163 		if (*p < ' ' || *p > 0x7e)
    164 			break;
    165 	}
    166 	if (i == len) {
    167 		printf("\"");
    168 		for (i = 0, p = essid; i < len; i++, p++)
    169 			printf("%c", *p);
    170 		printf("\"");
    171 	} else {
    172 		printf("0x");
    173 		for (i = 0, p = essid; i < len; i++, p++)
    174 			printf("%02x", *p);
    175 	}
    176 }
    177 
    178 void
    179 ieee80211_dump_pkt(u_int8_t *buf, int len, int rate, int rssi)
    180 {
    181 	struct ieee80211_frame *wh;
    182 	int i;
    183 
    184 	wh = (struct ieee80211_frame *)buf;
    185 	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
    186 	case IEEE80211_FC1_DIR_NODS:
    187 		printf("NODS %s", ether_sprintf(wh->i_addr2));
    188 		printf("->%s", ether_sprintf(wh->i_addr1));
    189 		printf("(%s)", ether_sprintf(wh->i_addr3));
    190 		break;
    191 	case IEEE80211_FC1_DIR_TODS:
    192 		printf("TODS %s", ether_sprintf(wh->i_addr2));
    193 		printf("->%s", ether_sprintf(wh->i_addr3));
    194 		printf("(%s)", ether_sprintf(wh->i_addr1));
    195 		break;
    196 	case IEEE80211_FC1_DIR_FROMDS:
    197 		printf("FRDS %s", ether_sprintf(wh->i_addr3));
    198 		printf("->%s", ether_sprintf(wh->i_addr1));
    199 		printf("(%s)", ether_sprintf(wh->i_addr2));
    200 		break;
    201 	case IEEE80211_FC1_DIR_DSTODS:
    202 		printf("DSDS %s", ether_sprintf((u_int8_t *)&wh[1]));
    203 		printf("->%s", ether_sprintf(wh->i_addr3));
    204 		printf("(%s", ether_sprintf(wh->i_addr2));
    205 		printf("->%s)", ether_sprintf(wh->i_addr1));
    206 		break;
    207 	}
    208 	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
    209 	case IEEE80211_FC0_TYPE_DATA:
    210 		printf(" data");
    211 		break;
    212 	case IEEE80211_FC0_TYPE_MGT:
    213 		printf(" %s", ieee80211_mgt_subtype_name[
    214 		    (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
    215 		    >> IEEE80211_FC0_SUBTYPE_SHIFT]);
    216 		break;
    217 	default:
    218 		printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
    219 		break;
    220 	}
    221 	if (wh->i_fc[1] & IEEE80211_FC1_WEP)
    222 		printf(" WEP");
    223 	if (rate >= 0)
    224 		printf(" %dM", rate / 2);
    225 	if (rssi >= 0)
    226 		printf(" +%d", rssi);
    227 	printf("\n");
    228 	if (len > 0) {
    229 		for (i = 0; i < len; i++) {
    230 			if ((i & 1) == 0)
    231 				printf(" ");
    232 			printf("%02x", buf[i]);
    233 		}
    234 		printf("\n");
    235 	}
    236 }
    237 
    238 int
    239 ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
    240 {
    241 #define	RV(v)	((v) & IEEE80211_RATE_VAL)
    242 	int i, j, ignore, error;
    243 	int okrate, badrate;
    244 	struct ieee80211_rateset *srs, *nrs;
    245 	u_int8_t r;
    246 
    247 	error = 0;
    248 	okrate = badrate = 0;
    249 	srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
    250 	nrs = &ni->ni_rates;
    251 	for (i = 0; i < nrs->rs_nrates; ) {
    252 		ignore = 0;
    253 		if (flags & IEEE80211_F_DOSORT) {
    254 			/*
    255 			 * Sort rates.
    256 			 */
    257 			for (j = i + 1; j < nrs->rs_nrates; j++) {
    258 				if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
    259 					r = nrs->rs_rates[i];
    260 					nrs->rs_rates[i] = nrs->rs_rates[j];
    261 					nrs->rs_rates[j] = r;
    262 				}
    263 			}
    264 		}
    265 		r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
    266 		badrate = r;
    267 		if (flags & IEEE80211_F_DOFRATE) {
    268 			/*
    269 			 * Apply fixed rate constraint.  Note that we do
    270 			 * not apply the constraint to basic rates as
    271 			 * otherwise we may not be able to associate if
    272 			 * the rate set we submit to the AP is invalid
    273 			 * (e.g. fix rate at 36Mb/s which is not a basic
    274 			 * rate for 11a operation).
    275 			 */
    276 			if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
    277 			    ic->ic_fixed_rate >= 0 &&
    278 			    r != RV(srs->rs_rates[ic->ic_fixed_rate]))
    279 				ignore++;
    280 		}
    281 		if (flags & IEEE80211_F_DONEGO) {
    282 			/*
    283 			 * Check against supported rates.
    284 			 */
    285 			for (j = 0; j < srs->rs_nrates; j++) {
    286 				if (r == RV(srs->rs_rates[j])) {
    287 					/*
    288 					 * Overwrite with the supported rate
    289 					 * value so any basic rate bit is set.
    290 					 * This insures that response we send
    291 					 * to stations have the necessary basic
    292 					 * rate bit set.
    293 					 */
    294 					nrs->rs_rates[i] = srs->rs_rates[j];
    295 					break;
    296 				}
    297 			}
    298 			if (j == srs->rs_nrates) {
    299 				/*
    300 				 * A rate in the node's rate set is not
    301 				 * supported.  If this is a basic rate and we
    302 				 * are operating as an AP then this is an error.
    303 				 * Otherwise we just discard/ignore the rate.
    304 				 * Note that this is important for 11b stations
    305 				 * when they want to associate with an 11g AP.
    306 				 */
    307 				if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
    308 				    (nrs->rs_rates[i] & IEEE80211_RATE_BASIC))
    309 					error++;
    310 				ignore++;
    311 			}
    312 		}
    313 		if (flags & IEEE80211_F_DODEL) {
    314 			/*
    315 			 * Delete unacceptable rates.
    316 			 */
    317 			if (ignore) {
    318 				nrs->rs_nrates--;
    319 				for (j = i; j < nrs->rs_nrates; j++)
    320 					nrs->rs_rates[j] = nrs->rs_rates[j + 1];
    321 				nrs->rs_rates[j] = 0;
    322 				continue;
    323 			}
    324 		}
    325 		if (!ignore)
    326 			okrate = nrs->rs_rates[i];
    327 		i++;
    328 	}
    329 	if (okrate == 0 || error != 0)
    330 		return badrate | IEEE80211_RATE_BASIC;
    331 	else
    332 		return RV(okrate);
    333 #undef RV
    334 }
    335 
    336 static int
    337 ieee80211_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int mgt)
    338 {
    339 	struct ifnet *ifp = &ic->ic_if;
    340 	struct ieee80211_node *ni;
    341 	enum ieee80211_state ostate;
    342 	ieee80211_node_critsec_decl(s);
    343 	int linkstate = LINK_STATE_DOWN;
    344 
    345 	ostate = ic->ic_state;
    346 	IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
    347 		ieee80211_state_name[ostate], ieee80211_state_name[nstate]));
    348 	ic->ic_state = nstate;			/* state transition */
    349 	ni = ic->ic_bss;			/* NB: no reference held */
    350 	switch (nstate) {
    351 	case IEEE80211_S_INIT:
    352 		switch (ostate) {
    353 		case IEEE80211_S_INIT:
    354 			break;
    355 		case IEEE80211_S_RUN:
    356 			switch (ic->ic_opmode) {
    357 			case IEEE80211_M_STA:
    358 				IEEE80211_SEND_MGMT(ic, ni,
    359 				    IEEE80211_FC0_SUBTYPE_DISASSOC,
    360 				    IEEE80211_REASON_ASSOC_LEAVE);
    361 				break;
    362 			case IEEE80211_M_HOSTAP:
    363 				ieee80211_node_critsec_begin(ic, s);
    364 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
    365 					if (ni->ni_associd == 0)
    366 						continue;
    367 					IEEE80211_SEND_MGMT(ic, ni,
    368 					    IEEE80211_FC0_SUBTYPE_DISASSOC,
    369 					    IEEE80211_REASON_ASSOC_LEAVE);
    370 				}
    371 				ieee80211_node_critsec_end(ic, s);
    372 				break;
    373 			default:
    374 				break;
    375 			}
    376 			/* FALLTHRU */
    377 		case IEEE80211_S_ASSOC:
    378 			switch (ic->ic_opmode) {
    379 			case IEEE80211_M_STA:
    380 				IEEE80211_SEND_MGMT(ic, ni,
    381 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
    382 				    IEEE80211_REASON_AUTH_LEAVE);
    383 				break;
    384 			case IEEE80211_M_HOSTAP:
    385 				ieee80211_node_critsec_begin(ic, s);
    386 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
    387 					IEEE80211_SEND_MGMT(ic, ni,
    388 					    IEEE80211_FC0_SUBTYPE_DEAUTH,
    389 					    IEEE80211_REASON_AUTH_LEAVE);
    390 				}
    391 				ieee80211_node_critsec_end(ic, s);
    392 				break;
    393 			default:
    394 				break;
    395 			}
    396 			/* FALLTHRU */
    397 		case IEEE80211_S_AUTH:
    398 		case IEEE80211_S_SCAN:
    399 			ic->ic_mgt_timer = 0;
    400 #ifdef __FreeBSD__
    401 			IF_DRAIN(&ic->ic_mgtq);
    402 #else
    403 			IF_PURGE(&ic->ic_mgtq);
    404 			IF_PURGE(&ic->ic_pwrsaveq);
    405 #endif
    406 			if (ic->ic_wep_ctx != NULL) {
    407 				free(ic->ic_wep_ctx, M_DEVBUF);
    408 				ic->ic_wep_ctx = NULL;
    409 			}
    410 			ieee80211_free_allnodes(ic);
    411 			break;
    412 		}
    413 		break;
    414 	case IEEE80211_S_SCAN:
    415 		ic->ic_flags &= ~IEEE80211_F_SIBSS;
    416 		/* initialize bss for probe request */
    417 		IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
    418 		IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
    419 		ni->ni_rates = ic->ic_sup_rates[
    420 			ieee80211_chan2mode(ic, ni->ni_chan)];
    421 		ni->ni_associd = 0;
    422 		ni->ni_rstamp = 0;
    423 		switch (ostate) {
    424 		case IEEE80211_S_INIT:
    425 			if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
    426 			    ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
    427 				/*
    428 				 * AP operation and we already have a channel;
    429 				 * bypass the scan and startup immediately.
    430 				 */
    431 				ieee80211_create_ibss(ic, ic->ic_des_chan);
    432 			} else {
    433 				ieee80211_begin_scan(ifp);
    434 			}
    435 			break;
    436 		case IEEE80211_S_SCAN:
    437 			/* scan next */
    438 			if (ic->ic_flags & IEEE80211_F_ASCAN) {
    439 				IEEE80211_SEND_MGMT(ic, ni,
    440 				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
    441 			}
    442 			break;
    443 		case IEEE80211_S_RUN:
    444 			/* beacon miss */
    445 			if (ifp->if_flags & IFF_DEBUG) {
    446 				/* XXX bssid clobbered above */
    447 				if_printf(ifp, "no recent beacons from %s;"
    448 				    " rescanning\n",
    449 				    ether_sprintf(ic->ic_bss->ni_bssid));
    450 			}
    451 			ieee80211_free_allnodes(ic);
    452 			/* FALLTHRU */
    453 		case IEEE80211_S_AUTH:
    454 		case IEEE80211_S_ASSOC:
    455 			/* timeout restart scan */
    456 			ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
    457 			if (ni != NULL) {
    458 				ni->ni_fails++;
    459 				ieee80211_unref_node(&ni);
    460 			}
    461 			ieee80211_begin_scan(ifp);
    462 			break;
    463 		}
    464 		break;
    465 	case IEEE80211_S_AUTH:
    466 		switch (ostate) {
    467 		case IEEE80211_S_INIT:
    468 			IEEE80211_DPRINTF(("%s: invalid transition\n",
    469 				__func__));
    470 			break;
    471 		case IEEE80211_S_SCAN:
    472 			IEEE80211_SEND_MGMT(ic, ni,
    473 			    IEEE80211_FC0_SUBTYPE_AUTH, 1);
    474 			break;
    475 		case IEEE80211_S_AUTH:
    476 		case IEEE80211_S_ASSOC:
    477 			switch (mgt) {
    478 			case IEEE80211_FC0_SUBTYPE_AUTH:
    479 				/* ??? */
    480 				IEEE80211_SEND_MGMT(ic, ni,
    481 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
    482 				break;
    483 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
    484 				/* ignore and retry scan on timeout */
    485 				break;
    486 			}
    487 			break;
    488 		case IEEE80211_S_RUN:
    489 			switch (mgt) {
    490 			case IEEE80211_FC0_SUBTYPE_AUTH:
    491 				IEEE80211_SEND_MGMT(ic, ni,
    492 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
    493 				ic->ic_state = ostate;	/* stay RUN */
    494 				break;
    495 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
    496 				/* try to reauth */
    497 				IEEE80211_SEND_MGMT(ic, ni,
    498 				    IEEE80211_FC0_SUBTYPE_AUTH, 1);
    499 				break;
    500 			}
    501 			break;
    502 		}
    503 		break;
    504 	case IEEE80211_S_ASSOC:
    505 		switch (ostate) {
    506 		case IEEE80211_S_INIT:
    507 		case IEEE80211_S_SCAN:
    508 		case IEEE80211_S_ASSOC:
    509 			IEEE80211_DPRINTF(("%s: invalid transition\n",
    510 				__func__));
    511 			break;
    512 		case IEEE80211_S_AUTH:
    513 			IEEE80211_SEND_MGMT(ic, ni,
    514 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
    515 			break;
    516 		case IEEE80211_S_RUN:
    517 			IEEE80211_SEND_MGMT(ic, ni,
    518 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
    519 			break;
    520 		}
    521 		break;
    522 	case IEEE80211_S_RUN:
    523 		linkstate = LINK_STATE_UP;
    524 		switch (ostate) {
    525 		case IEEE80211_S_INIT:
    526 		case IEEE80211_S_AUTH:
    527 		case IEEE80211_S_RUN:
    528 			IEEE80211_DPRINTF(("%s: invalid transition\n",
    529 				__func__));
    530 			break;
    531 		case IEEE80211_S_SCAN:		/* adhoc/hostap mode */
    532 		case IEEE80211_S_ASSOC:		/* infra mode */
    533 			IASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
    534 				("%s: bogus xmit rate %u setup\n", __func__,
    535 					ni->ni_txrate));
    536 			if (ifp->if_flags & IFF_DEBUG) {
    537 				if_printf(ifp, " ");
    538 				if (ic->ic_opmode == IEEE80211_M_STA)
    539 					printf("associated ");
    540 				else
    541 					printf("synchronized ");
    542 				printf("with %s ssid ",
    543 				    ether_sprintf(ni->ni_bssid));
    544 				ieee80211_print_essid(ic->ic_bss->ni_essid,
    545 				    ni->ni_esslen);
    546 				printf(" channel %d start %uMb\n",
    547 					ieee80211_chan2ieee(ic, ni->ni_chan),
    548 					IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
    549 			}
    550 			ic->ic_mgt_timer = 0;
    551 			(*ifp->if_start)(ifp);
    552 			break;
    553 		}
    554 		break;
    555 	}
    556 	if (ifp->if_link_state != linkstate) {
    557 		ifp->if_link_state = linkstate;
    558 		s = splnet();
    559 		rt_ifmsg(ifp);
    560 		splx(s);
    561 	}
    562 	return 0;
    563 }
    564