xref: /netbsd-src/sys/net80211/ieee80211_proto.c (revision d20841bb642898112fe68f0ad3f7b26dddf56f07)
1 /*	$NetBSD: ieee80211_proto.c,v 1.7 2004/01/13 23:37:30 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 1.6 2003/10/31 18:32:09 brooks Exp $");
37 #else
38 __KERNEL_RCSID(0, "$NetBSD: ieee80211_proto.c,v 1.7 2004/01/13 23:37:30 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 
124 #ifdef __FreeBSD__
125 	mtx_init(&ic->ic_mgtq.ifq_mtx, ifp->if_xname, "mgmt send q", MTX_DEF);
126 #endif
127 
128 	/* protocol state change handler */
129 	ic->ic_newstate = ieee80211_newstate;
130 
131 	/* initialize management frame handlers */
132 	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
133 	ic->ic_send_mgmt = ieee80211_send_mgmt;
134 }
135 
136 void
137 ieee80211_proto_detach(struct ifnet *ifp)
138 {
139 	struct ieee80211com *ic = (void *)ifp;
140 
141 #ifdef __FreeBSD__
142 	IF_DRAIN(&ic->ic_mgtq);
143 	mtx_destroy(&ic->ic_mgtq.ifq_mtx);
144 #else
145 	IF_PURGE(&ic->ic_mgtq);
146 	IF_PURGE(&ic->ic_pwrsaveq);
147 #endif
148 }
149 
150 void
151 ieee80211_print_essid(u_int8_t *essid, int len)
152 {
153 	int i;
154 	u_int8_t *p;
155 
156 	if (len > IEEE80211_NWID_LEN)
157 		len = IEEE80211_NWID_LEN;
158 	/* determine printable or not */
159 	for (i = 0, p = essid; i < len; i++, p++) {
160 		if (*p < ' ' || *p > 0x7e)
161 			break;
162 	}
163 	if (i == len) {
164 		printf("\"");
165 		for (i = 0, p = essid; i < len; i++, p++)
166 			printf("%c", *p);
167 		printf("\"");
168 	} else {
169 		printf("0x");
170 		for (i = 0, p = essid; i < len; i++, p++)
171 			printf("%02x", *p);
172 	}
173 }
174 
175 void
176 ieee80211_dump_pkt(u_int8_t *buf, int len, int rate, int rssi)
177 {
178 	struct ieee80211_frame *wh;
179 	int i;
180 
181 	wh = (struct ieee80211_frame *)buf;
182 	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
183 	case IEEE80211_FC1_DIR_NODS:
184 		printf("NODS %s", ether_sprintf(wh->i_addr2));
185 		printf("->%s", ether_sprintf(wh->i_addr1));
186 		printf("(%s)", ether_sprintf(wh->i_addr3));
187 		break;
188 	case IEEE80211_FC1_DIR_TODS:
189 		printf("TODS %s", ether_sprintf(wh->i_addr2));
190 		printf("->%s", ether_sprintf(wh->i_addr3));
191 		printf("(%s)", ether_sprintf(wh->i_addr1));
192 		break;
193 	case IEEE80211_FC1_DIR_FROMDS:
194 		printf("FRDS %s", ether_sprintf(wh->i_addr3));
195 		printf("->%s", ether_sprintf(wh->i_addr1));
196 		printf("(%s)", ether_sprintf(wh->i_addr2));
197 		break;
198 	case IEEE80211_FC1_DIR_DSTODS:
199 		printf("DSDS %s", ether_sprintf((u_int8_t *)&wh[1]));
200 		printf("->%s", ether_sprintf(wh->i_addr3));
201 		printf("(%s", ether_sprintf(wh->i_addr2));
202 		printf("->%s)", ether_sprintf(wh->i_addr1));
203 		break;
204 	}
205 	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
206 	case IEEE80211_FC0_TYPE_DATA:
207 		printf(" data");
208 		break;
209 	case IEEE80211_FC0_TYPE_MGT:
210 		printf(" %s", ieee80211_mgt_subtype_name[
211 		    (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
212 		    >> IEEE80211_FC0_SUBTYPE_SHIFT]);
213 		break;
214 	default:
215 		printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
216 		break;
217 	}
218 	if (wh->i_fc[1] & IEEE80211_FC1_WEP)
219 		printf(" WEP");
220 	if (rate >= 0)
221 		printf(" %dM", rate / 2);
222 	if (rssi >= 0)
223 		printf(" +%d", rssi);
224 	printf("\n");
225 	if (len > 0) {
226 		for (i = 0; i < len; i++) {
227 			if ((i & 1) == 0)
228 				printf(" ");
229 			printf("%02x", buf[i]);
230 		}
231 		printf("\n");
232 	}
233 }
234 
235 int
236 ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
237 {
238 #define	RV(v)	((v) & IEEE80211_RATE_VAL)
239 	int i, j, ignore, error;
240 	int okrate, badrate;
241 	struct ieee80211_rateset *srs, *nrs;
242 	u_int8_t r;
243 
244 	error = 0;
245 	okrate = badrate = 0;
246 	srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
247 	nrs = &ni->ni_rates;
248 	for (i = 0; i < nrs->rs_nrates; ) {
249 		ignore = 0;
250 		if (flags & IEEE80211_F_DOSORT) {
251 			/*
252 			 * Sort rates.
253 			 */
254 			for (j = i + 1; j < nrs->rs_nrates; j++) {
255 				if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
256 					r = nrs->rs_rates[i];
257 					nrs->rs_rates[i] = nrs->rs_rates[j];
258 					nrs->rs_rates[j] = r;
259 				}
260 			}
261 		}
262 		r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
263 		badrate = r;
264 		if (flags & IEEE80211_F_DOFRATE) {
265 			/*
266 			 * Apply fixed rate constraint.  Note that we do
267 			 * not apply the constraint to basic rates as
268 			 * otherwise we may not be able to associate if
269 			 * the rate set we submit to the AP is invalid
270 			 * (e.g. fix rate at 36Mb/s which is not a basic
271 			 * rate for 11a operation).
272 			 */
273 			if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
274 			    ic->ic_fixed_rate >= 0 &&
275 			    r != RV(srs->rs_rates[ic->ic_fixed_rate]))
276 				ignore++;
277 		}
278 		if (flags & IEEE80211_F_DONEGO) {
279 			/*
280 			 * Check against supported rates.
281 			 */
282 			for (j = 0; j < srs->rs_nrates; j++) {
283 				if (r == RV(srs->rs_rates[j]))
284 					break;
285 			}
286 			if (j == srs->rs_nrates) {
287 				/*
288 				 * A rate in the node's rate set is not
289 				 * supported.  If this is a basic rate and we
290 				 * are operating as an AP then this is an error.
291 				 * Otherwise we just discard/ignore the rate.
292 				 * Note that this is important for 11b stations
293 				 * when they want to associate with an 11g AP.
294 				 */
295 				if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
296 				    (nrs->rs_rates[i] & IEEE80211_RATE_BASIC))
297 					error++;
298 				ignore++;
299 			}
300 		}
301 		if (flags & IEEE80211_F_DODEL) {
302 			/*
303 			 * Delete unacceptable rates.
304 			 */
305 			if (ignore) {
306 				nrs->rs_nrates--;
307 				for (j = i; j < nrs->rs_nrates; j++)
308 					nrs->rs_rates[j] = nrs->rs_rates[j + 1];
309 				nrs->rs_rates[j] = 0;
310 				continue;
311 			}
312 		}
313 		if (!ignore)
314 			okrate = nrs->rs_rates[i];
315 		i++;
316 	}
317 	if (okrate == 0 || error != 0)
318 		return badrate | IEEE80211_RATE_BASIC;
319 	else
320 		return RV(okrate);
321 #undef RV
322 }
323 
324 static int
325 ieee80211_newstate(struct ieee80211com *ic, enum ieee80211_state nstate, int mgt)
326 {
327 	struct ifnet *ifp = &ic->ic_if;
328 	struct ieee80211_node *ni;
329 	enum ieee80211_state ostate;
330 	ieee80211_node_critsec_decl(s);
331 
332 	ostate = ic->ic_state;
333 	IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
334 		ieee80211_state_name[ostate], ieee80211_state_name[nstate]));
335 	ic->ic_state = nstate;			/* state transition */
336 	ni = ic->ic_bss;			/* NB: no reference held */
337 	switch (nstate) {
338 	case IEEE80211_S_INIT:
339 		switch (ostate) {
340 		case IEEE80211_S_INIT:
341 			break;
342 		case IEEE80211_S_RUN:
343 			switch (ic->ic_opmode) {
344 			case IEEE80211_M_STA:
345 				IEEE80211_SEND_MGMT(ic, ni,
346 				    IEEE80211_FC0_SUBTYPE_DISASSOC,
347 				    IEEE80211_REASON_ASSOC_LEAVE);
348 				break;
349 			case IEEE80211_M_HOSTAP:
350 				ieee80211_node_critsec_begin(ic, s);
351 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
352 					if (ni->ni_associd == 0)
353 						continue;
354 					IEEE80211_SEND_MGMT(ic, ni,
355 					    IEEE80211_FC0_SUBTYPE_DISASSOC,
356 					    IEEE80211_REASON_ASSOC_LEAVE);
357 				}
358 				ieee80211_node_critsec_end(ic, s);
359 				break;
360 			default:
361 				break;
362 			}
363 			/* FALLTHRU */
364 		case IEEE80211_S_ASSOC:
365 			switch (ic->ic_opmode) {
366 			case IEEE80211_M_STA:
367 				IEEE80211_SEND_MGMT(ic, ni,
368 				    IEEE80211_FC0_SUBTYPE_DEAUTH,
369 				    IEEE80211_REASON_AUTH_LEAVE);
370 				break;
371 			case IEEE80211_M_HOSTAP:
372 				ieee80211_node_critsec_begin(ic, s);
373 				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
374 					IEEE80211_SEND_MGMT(ic, ni,
375 					    IEEE80211_FC0_SUBTYPE_DEAUTH,
376 					    IEEE80211_REASON_AUTH_LEAVE);
377 				}
378 				ieee80211_node_critsec_end(ic, s);
379 				break;
380 			default:
381 				break;
382 			}
383 			/* FALLTHRU */
384 		case IEEE80211_S_AUTH:
385 		case IEEE80211_S_SCAN:
386 			ic->ic_mgt_timer = 0;
387 #ifdef __FreeBSD__
388 			IF_DRAIN(&ic->ic_mgtq);
389 #else
390 			IF_PURGE(&ic->ic_mgtq);
391 			IF_PURGE(&ic->ic_pwrsaveq);
392 #endif
393 			if (ic->ic_wep_ctx != NULL) {
394 				free(ic->ic_wep_ctx, M_DEVBUF);
395 				ic->ic_wep_ctx = NULL;
396 			}
397 			ieee80211_free_allnodes(ic);
398 			break;
399 		}
400 		break;
401 	case IEEE80211_S_SCAN:
402 		ic->ic_flags &= ~IEEE80211_F_SIBSS;
403 		/* initialize bss for probe request */
404 		IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
405 		IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
406 		ni->ni_rates = ic->ic_sup_rates[
407 			ieee80211_chan2mode(ic, ni->ni_chan)];
408 		ni->ni_associd = 0;
409 		ni->ni_rstamp = 0;
410 		switch (ostate) {
411 		case IEEE80211_S_INIT:
412 			if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
413 			    ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
414 				/*
415 				 * AP operation and we already have a channel;
416 				 * bypass the scan and startup immediately.
417 				 */
418 				ieee80211_create_ibss(ic, ic->ic_des_chan);
419 			} else {
420 				ieee80211_begin_scan(ifp);
421 			}
422 			break;
423 		case IEEE80211_S_SCAN:
424 			/* scan next */
425 			if (ic->ic_flags & IEEE80211_F_ASCAN) {
426 				IEEE80211_SEND_MGMT(ic, ni,
427 				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
428 			}
429 			break;
430 		case IEEE80211_S_RUN:
431 			/* beacon miss */
432 			if (ifp->if_flags & IFF_DEBUG) {
433 				/* XXX bssid clobbered above */
434 				if_printf(ifp, "no recent beacons from %s;"
435 				    " rescanning\n",
436 				    ether_sprintf(ic->ic_bss->ni_bssid));
437 			}
438 			ieee80211_free_allnodes(ic);
439 			/* FALLTHRU */
440 		case IEEE80211_S_AUTH:
441 		case IEEE80211_S_ASSOC:
442 			/* timeout restart scan */
443 			ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
444 			if (ni != NULL) {
445 				ni->ni_fails++;
446 				ieee80211_unref_node(&ni);
447 			}
448 			ieee80211_begin_scan(ifp);
449 			break;
450 		}
451 		break;
452 	case IEEE80211_S_AUTH:
453 		switch (ostate) {
454 		case IEEE80211_S_INIT:
455 			IEEE80211_DPRINTF(("%s: invalid transition\n",
456 				__func__));
457 			break;
458 		case IEEE80211_S_SCAN:
459 			IEEE80211_SEND_MGMT(ic, ni,
460 			    IEEE80211_FC0_SUBTYPE_AUTH, 1);
461 			break;
462 		case IEEE80211_S_AUTH:
463 		case IEEE80211_S_ASSOC:
464 			switch (mgt) {
465 			case IEEE80211_FC0_SUBTYPE_AUTH:
466 				/* ??? */
467 				IEEE80211_SEND_MGMT(ic, ni,
468 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
469 				break;
470 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
471 				/* ignore and retry scan on timeout */
472 				break;
473 			}
474 			break;
475 		case IEEE80211_S_RUN:
476 			switch (mgt) {
477 			case IEEE80211_FC0_SUBTYPE_AUTH:
478 				IEEE80211_SEND_MGMT(ic, ni,
479 				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
480 				ic->ic_state = ostate;	/* stay RUN */
481 				break;
482 			case IEEE80211_FC0_SUBTYPE_DEAUTH:
483 				/* try to reauth */
484 				IEEE80211_SEND_MGMT(ic, ni,
485 				    IEEE80211_FC0_SUBTYPE_AUTH, 1);
486 				break;
487 			}
488 			break;
489 		}
490 		break;
491 	case IEEE80211_S_ASSOC:
492 		switch (ostate) {
493 		case IEEE80211_S_INIT:
494 		case IEEE80211_S_SCAN:
495 		case IEEE80211_S_ASSOC:
496 			IEEE80211_DPRINTF(("%s: invalid transition\n",
497 				__func__));
498 			break;
499 		case IEEE80211_S_AUTH:
500 			IEEE80211_SEND_MGMT(ic, ni,
501 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
502 			break;
503 		case IEEE80211_S_RUN:
504 			IEEE80211_SEND_MGMT(ic, ni,
505 			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
506 			break;
507 		}
508 		break;
509 	case IEEE80211_S_RUN:
510 		switch (ostate) {
511 		case IEEE80211_S_INIT:
512 		case IEEE80211_S_AUTH:
513 		case IEEE80211_S_RUN:
514 			IEEE80211_DPRINTF(("%s: invalid transition\n",
515 				__func__));
516 			break;
517 		case IEEE80211_S_SCAN:		/* adhoc/hostap mode */
518 		case IEEE80211_S_ASSOC:		/* infra mode */
519 			IASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
520 				("%s: bogus xmit rate %u setup\n", __func__,
521 					ni->ni_txrate));
522 			if (ifp->if_flags & IFF_DEBUG) {
523 				if_printf(ifp, " ");
524 				if (ic->ic_opmode == IEEE80211_M_STA)
525 					printf("associated ");
526 				else
527 					printf("synchronized ");
528 				printf("with %s ssid ",
529 				    ether_sprintf(ni->ni_bssid));
530 				ieee80211_print_essid(ic->ic_bss->ni_essid,
531 				    ni->ni_esslen);
532 				printf(" channel %d start %uMb\n",
533 					ieee80211_chan2ieee(ic, ni->ni_chan),
534 					IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
535 			}
536 			ic->ic_mgt_timer = 0;
537 			(*ifp->if_start)(ifp);
538 			break;
539 		}
540 		break;
541 	}
542 	return 0;
543 }
544