xref: /netbsd-src/sys/net80211/ieee80211_proto.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8)
1 /*	$NetBSD: ieee80211_proto.c,v 1.8 2004/04/30 23:58:20 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 1.8 2004/04/30 23:58:20 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 #define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
92 
93 const char *ieee80211_mgt_subtype_name[] = {
94 	"assoc_req",	"assoc_resp",	"reassoc_req",	"reassoc_resp",
95 	"probe_req",	"probe_resp",	"reserved#6",	"reserved#7",
96 	"beacon",	"atim",		"disassoc",	"auth",
97 	"deauth",	"reserved#13",	"reserved#14",	"reserved#15"
98 };
99 const char *ieee80211_state_name[IEEE80211_S_MAX] = {
100 	"INIT",		/* IEEE80211_S_INIT */
101 	"SCAN",		/* IEEE80211_S_SCAN */
102 	"AUTH",		/* IEEE80211_S_AUTH */
103 	"ASSOC",	/* IEEE80211_S_ASSOC */
104 	"RUN"		/* IEEE80211_S_RUN */
105 };
106 
107 static int ieee80211_newstate(struct ieee80211com *, enum ieee80211_state, int);
108 
109 void
110 ieee80211_proto_attach(struct ifnet *ifp)
111 {
112 	struct ieee80211com *ic = (void *)ifp;
113 
114 	ifp->if_hdrlen = sizeof(struct ieee80211_frame);
115 
116 #ifdef notdef
117 	ic->ic_rtsthreshold = IEEE80211_RTS_DEFAULT;
118 #else
119 	ic->ic_rtsthreshold = IEEE80211_RTS_MAX;
120 #endif
121 	ic->ic_fragthreshold = 2346;		/* XXX not used yet */
122 	ic->ic_fixed_rate = -1;			/* no fixed rate */
123 	ic->ic_protmode = IEEE80211_PROT_CTSONLY;
124 
125 #ifdef __FreeBSD__
126 	mtx_init(&ic->ic_mgtq.ifq_mtx, ifp->if_xname, "mgmt send q", MTX_DEF);
127 #endif
128 
129 	/* protocol state change handler */
130 	ic->ic_newstate = ieee80211_newstate;
131 
132 	/* initialize management frame handlers */
133 	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
134 	ic->ic_send_mgmt = ieee80211_send_mgmt;
135 }
136 
137 void
138 ieee80211_proto_detach(struct ifnet *ifp)
139 {
140 	struct ieee80211com *ic = (void *)ifp;
141 
142 #ifdef __FreeBSD__
143 	IF_DRAIN(&ic->ic_mgtq);
144 	mtx_destroy(&ic->ic_mgtq.ifq_mtx);
145 #else
146 	IF_PURGE(&ic->ic_mgtq);
147 	IF_PURGE(&ic->ic_pwrsaveq);
148 #endif
149 }
150 
151 void
152 ieee80211_print_essid(u_int8_t *essid, int len)
153 {
154 	int i;
155 	u_int8_t *p;
156 
157 	if (len > IEEE80211_NWID_LEN)
158 		len = IEEE80211_NWID_LEN;
159 	/* determine printable or not */
160 	for (i = 0, p = essid; i < len; i++, p++) {
161 		if (*p < ' ' || *p > 0x7e)
162 			break;
163 	}
164 	if (i == len) {
165 		printf("\"");
166 		for (i = 0, p = essid; i < len; i++, p++)
167 			printf("%c", *p);
168 		printf("\"");
169 	} else {
170 		printf("0x");
171 		for (i = 0, p = essid; i < len; i++, p++)
172 			printf("%02x", *p);
173 	}
174 }
175 
176 void
177 ieee80211_dump_pkt(u_int8_t *buf, int len, int rate, int rssi)
178 {
179 	struct ieee80211_frame *wh;
180 	int i;
181 
182 	wh = (struct ieee80211_frame *)buf;
183 	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
184 	case IEEE80211_FC1_DIR_NODS:
185 		printf("NODS %s", ether_sprintf(wh->i_addr2));
186 		printf("->%s", ether_sprintf(wh->i_addr1));
187 		printf("(%s)", ether_sprintf(wh->i_addr3));
188 		break;
189 	case IEEE80211_FC1_DIR_TODS:
190 		printf("TODS %s", ether_sprintf(wh->i_addr2));
191 		printf("->%s", ether_sprintf(wh->i_addr3));
192 		printf("(%s)", ether_sprintf(wh->i_addr1));
193 		break;
194 	case IEEE80211_FC1_DIR_FROMDS:
195 		printf("FRDS %s", ether_sprintf(wh->i_addr3));
196 		printf("->%s", ether_sprintf(wh->i_addr1));
197 		printf("(%s)", ether_sprintf(wh->i_addr2));
198 		break;
199 	case IEEE80211_FC1_DIR_DSTODS:
200 		printf("DSDS %s", ether_sprintf((u_int8_t *)&wh[1]));
201 		printf("->%s", ether_sprintf(wh->i_addr3));
202 		printf("(%s", ether_sprintf(wh->i_addr2));
203 		printf("->%s)", ether_sprintf(wh->i_addr1));
204 		break;
205 	}
206 	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
207 	case IEEE80211_FC0_TYPE_DATA:
208 		printf(" data");
209 		break;
210 	case IEEE80211_FC0_TYPE_MGT:
211 		printf(" %s", ieee80211_mgt_subtype_name[
212 		    (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
213 		    >> IEEE80211_FC0_SUBTYPE_SHIFT]);
214 		break;
215 	default:
216 		printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
217 		break;
218 	}
219 	if (wh->i_fc[1] & IEEE80211_FC1_WEP)
220 		printf(" WEP");
221 	if (rate >= 0)
222 		printf(" %dM", rate / 2);
223 	if (rssi >= 0)
224 		printf(" +%d", rssi);
225 	printf("\n");
226 	if (len > 0) {
227 		for (i = 0; i < len; i++) {
228 			if ((i & 1) == 0)
229 				printf(" ");
230 			printf("%02x", buf[i]);
231 		}
232 		printf("\n");
233 	}
234 }
235 
236 int
237 ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
238 {
239 #define	RV(v)	((v) & IEEE80211_RATE_VAL)
240 	int i, j, ignore, error;
241 	int okrate, badrate;
242 	struct ieee80211_rateset *srs, *nrs;
243 	u_int8_t r;
244 
245 	error = 0;
246 	okrate = badrate = 0;
247 	srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
248 	nrs = &ni->ni_rates;
249 	for (i = 0; i < nrs->rs_nrates; ) {
250 		ignore = 0;
251 		if (flags & IEEE80211_F_DOSORT) {
252 			/*
253 			 * Sort rates.
254 			 */
255 			for (j = i + 1; j < nrs->rs_nrates; j++) {
256 				if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
257 					r = nrs->rs_rates[i];
258 					nrs->rs_rates[i] = nrs->rs_rates[j];
259 					nrs->rs_rates[j] = r;
260 				}
261 			}
262 		}
263 		r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
264 		badrate = r;
265 		if (flags & IEEE80211_F_DOFRATE) {
266 			/*
267 			 * Apply fixed rate constraint.  Note that we do
268 			 * not apply the constraint to basic rates as
269 			 * otherwise we may not be able to associate if
270 			 * the rate set we submit to the AP is invalid
271 			 * (e.g. fix rate at 36Mb/s which is not a basic
272 			 * rate for 11a operation).
273 			 */
274 			if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
275 			    ic->ic_fixed_rate >= 0 &&
276 			    r != RV(srs->rs_rates[ic->ic_fixed_rate]))
277 				ignore++;
278 		}
279 		if (flags & IEEE80211_F_DONEGO) {
280 			/*
281 			 * Check against supported rates.
282 			 */
283 			for (j = 0; j < srs->rs_nrates; j++) {
284 				if (r == RV(srs->rs_rates[j])) {
285 					/*
286 					 * Overwrite with the supported rate
287 					 * value so any basic rate bit is set.
288 					 * This insures that response we send
289 					 * to stations have the necessary basic
290 					 * rate bit set.
291 					 */
292 					nrs->rs_rates[i] = srs->rs_rates[j];
293 					break;
294 				}
295 			}
296 			if (j == srs->rs_nrates) {
297 				/*
298 				 * A rate in the node's rate set is not
299 				 * supported.  If this is a basic rate and we
300 				 * are operating as an AP then this is an error.
301 				 * Otherwise we just discard/ignore the rate.
302 				 * Note that this is important for 11b stations
303 				 * when they want to associate with an 11g AP.
304 				 */
305 				if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
306 				    (nrs->rs_rates[i] & IEEE80211_RATE_BASIC))
307 					error++;
308 				ignore++;
309 			}
310 		}
311 		if (flags & IEEE80211_F_DODEL) {
312 			/*
313 			 * Delete unacceptable rates.
314 			 */
315 			if (ignore) {
316 				nrs->rs_nrates--;
317 				for (j = i; j < nrs->rs_nrates; j++)
318 					nrs->rs_rates[j] = nrs->rs_rates[j + 1];
319 				nrs->rs_rates[j] = 0;
320 				continue;
321 			}
322 		}
323 		if (!ignore)
324 			okrate = nrs->rs_rates[i];
325 		i++;
326 	}
327 	if (okrate == 0 || error != 0)
328 		return badrate | IEEE80211_RATE_BASIC;
329 	else
330 		return RV(okrate);
331 #undef RV
332 }
333 
334 static int
335 ieee80211_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int mgt)
336 {
337 	struct ifnet *ifp = &ic->ic_if;
338 	struct ieee80211_node *ni;
339 	enum ieee80211_state ostate;
340 	ieee80211_node_critsec_decl(s);
341 
342 	ostate = ic->ic_state;
343 	IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
344 		ieee80211_state_name[ostate], ieee80211_state_name[nstate]));
345 	ic->ic_state = nstate;			/* state transition */
346 	ni = ic->ic_bss;			/* NB: no reference held */
347 	switch (nstate) {
348 	case IEEE80211_S_INIT:
349 		switch (ostate) {
350 		case IEEE80211_S_INIT:
351 			break;
352 		case IEEE80211_S_RUN:
353 			switch (ic->ic_opmode) {
354 			case IEEE80211_M_STA:
355 				IEEE80211_SEND_MGMT(ic, ni,
356 				    IEEE80211_FC0_SUBTYPE_DISASSOC,
357 				    IEEE80211_REASON_ASSOC_LEAVE);
358 				break;
359 			case IEEE80211_M_HOSTAP:
360 				ieee80211_node_critsec_begin(ic, s);
361 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
362 					if (ni->ni_associd == 0)
363 						continue;
364 					IEEE80211_SEND_MGMT(ic, ni,
365 					    IEEE80211_FC0_SUBTYPE_DISASSOC,
366 					    IEEE80211_REASON_ASSOC_LEAVE);
367 				}
368 				ieee80211_node_critsec_end(ic, s);
369 				break;
370 			default:
371 				break;
372 			}
373 			/* FALLTHRU */
374 		case IEEE80211_S_ASSOC:
375 			switch (ic->ic_opmode) {
376 			case IEEE80211_M_STA:
377 				IEEE80211_SEND_MGMT(ic, ni,
378 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
379 				    IEEE80211_REASON_AUTH_LEAVE);
380 				break;
381 			case IEEE80211_M_HOSTAP:
382 				ieee80211_node_critsec_begin(ic, s);
383 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
384 					IEEE80211_SEND_MGMT(ic, ni,
385 					    IEEE80211_FC0_SUBTYPE_DEAUTH,
386 					    IEEE80211_REASON_AUTH_LEAVE);
387 				}
388 				ieee80211_node_critsec_end(ic, s);
389 				break;
390 			default:
391 				break;
392 			}
393 			/* FALLTHRU */
394 		case IEEE80211_S_AUTH:
395 		case IEEE80211_S_SCAN:
396 			ic->ic_mgt_timer = 0;
397 #ifdef __FreeBSD__
398 			IF_DRAIN(&ic->ic_mgtq);
399 #else
400 			IF_PURGE(&ic->ic_mgtq);
401 			IF_PURGE(&ic->ic_pwrsaveq);
402 #endif
403 			if (ic->ic_wep_ctx != NULL) {
404 				free(ic->ic_wep_ctx, M_DEVBUF);
405 				ic->ic_wep_ctx = NULL;
406 			}
407 			ieee80211_free_allnodes(ic);
408 			break;
409 		}
410 		break;
411 	case IEEE80211_S_SCAN:
412 		ic->ic_flags &= ~IEEE80211_F_SIBSS;
413 		/* initialize bss for probe request */
414 		IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
415 		IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
416 		ni->ni_rates = ic->ic_sup_rates[
417 			ieee80211_chan2mode(ic, ni->ni_chan)];
418 		ni->ni_associd = 0;
419 		ni->ni_rstamp = 0;
420 		switch (ostate) {
421 		case IEEE80211_S_INIT:
422 			if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
423 			    ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
424 				/*
425 				 * AP operation and we already have a channel;
426 				 * bypass the scan and startup immediately.
427 				 */
428 				ieee80211_create_ibss(ic, ic->ic_des_chan);
429 			} else {
430 				ieee80211_begin_scan(ifp);
431 			}
432 			break;
433 		case IEEE80211_S_SCAN:
434 			/* scan next */
435 			if (ic->ic_flags & IEEE80211_F_ASCAN) {
436 				IEEE80211_SEND_MGMT(ic, ni,
437 				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
438 			}
439 			break;
440 		case IEEE80211_S_RUN:
441 			/* beacon miss */
442 			if (ifp->if_flags & IFF_DEBUG) {
443 				/* XXX bssid clobbered above */
444 				if_printf(ifp, "no recent beacons from %s;"
445 				    " rescanning\n",
446 				    ether_sprintf(ic->ic_bss->ni_bssid));
447 			}
448 			ieee80211_free_allnodes(ic);
449 			/* FALLTHRU */
450 		case IEEE80211_S_AUTH:
451 		case IEEE80211_S_ASSOC:
452 			/* timeout restart scan */
453 			ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
454 			if (ni != NULL) {
455 				ni->ni_fails++;
456 				ieee80211_unref_node(&ni);
457 			}
458 			ieee80211_begin_scan(ifp);
459 			break;
460 		}
461 		break;
462 	case IEEE80211_S_AUTH:
463 		switch (ostate) {
464 		case IEEE80211_S_INIT:
465 			IEEE80211_DPRINTF(("%s: invalid transition\n",
466 				__func__));
467 			break;
468 		case IEEE80211_S_SCAN:
469 			IEEE80211_SEND_MGMT(ic, ni,
470 			    IEEE80211_FC0_SUBTYPE_AUTH, 1);
471 			break;
472 		case IEEE80211_S_AUTH:
473 		case IEEE80211_S_ASSOC:
474 			switch (mgt) {
475 			case IEEE80211_FC0_SUBTYPE_AUTH:
476 				/* ??? */
477 				IEEE80211_SEND_MGMT(ic, ni,
478 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
479 				break;
480 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
481 				/* ignore and retry scan on timeout */
482 				break;
483 			}
484 			break;
485 		case IEEE80211_S_RUN:
486 			switch (mgt) {
487 			case IEEE80211_FC0_SUBTYPE_AUTH:
488 				IEEE80211_SEND_MGMT(ic, ni,
489 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
490 				ic->ic_state = ostate;	/* stay RUN */
491 				break;
492 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
493 				/* try to reauth */
494 				IEEE80211_SEND_MGMT(ic, ni,
495 				    IEEE80211_FC0_SUBTYPE_AUTH, 1);
496 				break;
497 			}
498 			break;
499 		}
500 		break;
501 	case IEEE80211_S_ASSOC:
502 		switch (ostate) {
503 		case IEEE80211_S_INIT:
504 		case IEEE80211_S_SCAN:
505 		case IEEE80211_S_ASSOC:
506 			IEEE80211_DPRINTF(("%s: invalid transition\n",
507 				__func__));
508 			break;
509 		case IEEE80211_S_AUTH:
510 			IEEE80211_SEND_MGMT(ic, ni,
511 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
512 			break;
513 		case IEEE80211_S_RUN:
514 			IEEE80211_SEND_MGMT(ic, ni,
515 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
516 			break;
517 		}
518 		break;
519 	case IEEE80211_S_RUN:
520 		switch (ostate) {
521 		case IEEE80211_S_INIT:
522 		case IEEE80211_S_AUTH:
523 		case IEEE80211_S_RUN:
524 			IEEE80211_DPRINTF(("%s: invalid transition\n",
525 				__func__));
526 			break;
527 		case IEEE80211_S_SCAN:		/* adhoc/hostap mode */
528 		case IEEE80211_S_ASSOC:		/* infra mode */
529 			IASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
530 				("%s: bogus xmit rate %u setup\n", __func__,
531 					ni->ni_txrate));
532 			if (ifp->if_flags & IFF_DEBUG) {
533 				if_printf(ifp, " ");
534 				if (ic->ic_opmode == IEEE80211_M_STA)
535 					printf("associated ");
536 				else
537 					printf("synchronized ");
538 				printf("with %s ssid ",
539 				    ether_sprintf(ni->ni_bssid));
540 				ieee80211_print_essid(ic->ic_bss->ni_essid,
541 				    ni->ni_esslen);
542 				printf(" channel %d start %uMb\n",
543 					ieee80211_chan2ieee(ic, ni->ni_chan),
544 					IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
545 			}
546 			ic->ic_mgt_timer = 0;
547 			(*ifp->if_start)(ifp);
548 			break;
549 		}
550 		break;
551 	}
552 	return 0;
553 }
554