ieee80211_proto.c revision 116904 
1/*-
2 * Copyright (c) 2001 Atsushi Onoe
3 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * Alternatively, this software may be distributed under the terms of the
18 * GNU General Public License ("GPL") version 2 as published by the Free
19 * Software Foundation.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33#include <sys/cdefs.h>
34__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_proto.c 116904 2003-06-27 05:13:52Z sam $");
35
36/*
37 * IEEE 802.11 protocol support.
38 */
39
40#include "opt_inet.h"
41
42#include <sys/param.h>
43#include <sys/systm.h>
44#include <sys/mbuf.h>
45#include <sys/malloc.h>
46#include <sys/kernel.h>
47#include <sys/socket.h>
48#include <sys/sockio.h>
49#include <sys/endian.h>
50#include <sys/errno.h>
51#include <sys/bus.h>
52#include <sys/proc.h>
53#include <sys/sysctl.h>
54
55#include <machine/atomic.h>
56
57#include <net/if.h>
58#include <net/if_dl.h>
59#include <net/if_media.h>
60#include <net/if_arp.h>
61#include <net/ethernet.h>
62#include <net/if_llc.h>
63
64#include <net80211/ieee80211_var.h>
65
66#include <net/bpf.h>
67
68#ifdef INET
69#include <netinet/in.h>
70#include <netinet/if_ether.h>
71#endif
72
73#define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
74
75const char *ieee80211_mgt_subtype_name[] = {
76	"assoc_req",	"assoc_resp",	"reassoc_req",	"reassoc_resp",
77	"probe_req",	"probe_resp",	"reserved#6",	"reserved#7",
78	"beacon",	"atim",		"disassoc",	"auth",
79	"deauth",	"reserved#13",	"reserved#14",	"reserved#15"
80};
81
82void
83ieee80211_proto_attach(struct ifnet *ifp)
84{
85	struct ieee80211com *ic = (void *)ifp;
86
87	ifp->if_hdrlen = sizeof(struct ieee80211_frame);
88
89#ifdef notdef
90	ic->ic_rtsthreshold = IEEE80211_RTS_DEFAULT;
91#else
92	ic->ic_rtsthreshold = IEEE80211_RTS_MAX;
93#endif
94	ic->ic_fragthreshold = 2346;		/* XXX not used yet */
95	ic->ic_fixed_rate = -1;			/* no fixed rate */
96
97	mtx_init(&ic->ic_mgtq.ifq_mtx, ifp->if_name, "mgmt send q", MTX_DEF);
98
99	/* initialize management frame handlers */
100	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
101	ic->ic_send_mgmt = ieee80211_send_mgmt;
102}
103
104void
105ieee80211_proto_detach(struct ifnet *ifp)
106{
107	struct ieee80211com *ic = (void *)ifp;
108
109	IF_DRAIN(&ic->ic_mgtq);
110	mtx_destroy(&ic->ic_mgtq.ifq_mtx);
111}
112
113void
114ieee80211_print_essid(u_int8_t *essid, int len)
115{
116	int i;
117	u_int8_t *p;
118
119	if (len > IEEE80211_NWID_LEN)
120		len = IEEE80211_NWID_LEN;
121	/* determine printable or not */
122	for (i = 0, p = essid; i < len; i++, p++) {
123		if (*p < ' ' || *p > 0x7e)
124			break;
125	}
126	if (i == len) {
127		printf("\"");
128		for (i = 0, p = essid; i < len; i++, p++)
129			printf("%c", *p);
130		printf("\"");
131	} else {
132		printf("0x");
133		for (i = 0, p = essid; i < len; i++, p++)
134			printf("%02x", *p);
135	}
136}
137
138void
139ieee80211_dump_pkt(u_int8_t *buf, int len, int rate, int rssi)
140{
141	struct ieee80211_frame *wh;
142	int i;
143
144	wh = (struct ieee80211_frame *)buf;
145	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
146	case IEEE80211_FC1_DIR_NODS:
147		printf("NODS %s", ether_sprintf(wh->i_addr2));
148		printf("->%s", ether_sprintf(wh->i_addr1));
149		printf("(%s)", ether_sprintf(wh->i_addr3));
150		break;
151	case IEEE80211_FC1_DIR_TODS:
152		printf("TODS %s", ether_sprintf(wh->i_addr2));
153		printf("->%s", ether_sprintf(wh->i_addr3));
154		printf("(%s)", ether_sprintf(wh->i_addr1));
155		break;
156	case IEEE80211_FC1_DIR_FROMDS:
157		printf("FRDS %s", ether_sprintf(wh->i_addr3));
158		printf("->%s", ether_sprintf(wh->i_addr1));
159		printf("(%s)", ether_sprintf(wh->i_addr2));
160		break;
161	case IEEE80211_FC1_DIR_DSTODS:
162		printf("DSDS %s", ether_sprintf((u_int8_t *)&wh[1]));
163		printf("->%s", ether_sprintf(wh->i_addr3));
164		printf("(%s", ether_sprintf(wh->i_addr2));
165		printf("->%s)", ether_sprintf(wh->i_addr1));
166		break;
167	}
168	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
169	case IEEE80211_FC0_TYPE_DATA:
170		printf(" data");
171		break;
172	case IEEE80211_FC0_TYPE_MGT:
173		printf(" %s", ieee80211_mgt_subtype_name[
174		    (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
175		    >> IEEE80211_FC0_SUBTYPE_SHIFT]);
176		break;
177	default:
178		printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
179		break;
180	}
181	if (wh->i_fc[1] & IEEE80211_FC1_WEP)
182		printf(" WEP");
183	if (rate >= 0)
184		printf(" %dM", rate / 2);
185	if (rssi >= 0)
186		printf(" +%d", rssi);
187	printf("\n");
188	if (len > 0) {
189		for (i = 0; i < len; i++) {
190			if ((i & 1) == 0)
191				printf(" ");
192			printf("%02x", buf[i]);
193		}
194		printf("\n");
195	}
196}
197
198int
199ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
200{
201#define	RV(v)	((v) & IEEE80211_RATE_VAL)
202	int i, j, ignore, error;
203	int okrate, badrate;
204	struct ieee80211_rateset *srs, *nrs;
205	u_int8_t r;
206
207	error = 0;
208	okrate = badrate = 0;
209	srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
210	nrs = &ni->ni_rates;
211	for (i = 0; i < ni->ni_rates.rs_nrates; ) {
212		ignore = 0;
213		if (flags & IEEE80211_F_DOSORT) {
214			/*
215			 * Sort rates.
216			 */
217			for (j = i + 1; j < nrs->rs_nrates; j++) {
218				if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
219					r = nrs->rs_rates[i];
220					nrs->rs_rates[i] = nrs->rs_rates[j];
221					nrs->rs_rates[j] = r;
222				}
223			}
224		}
225		r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
226		badrate = r;
227		if (flags & IEEE80211_F_DOFRATE) {
228			/*
229			 * Apply fixed rate constraint.  Note that we do
230			 * not apply the constraint to basic rates as
231			 * otherwise we may not be able to associate if
232			 * the rate set we submit to the AP is invalid
233			 * (e.g. fix rate at 36Mb/s which is not a basic
234			 * rate for 11a operation).
235			 */
236			if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
237			    ic->ic_fixed_rate >= 0 &&
238			    r != RV(srs->rs_rates[ic->ic_fixed_rate]))
239				ignore++;
240		}
241		if (flags & IEEE80211_F_DONEGO) {
242			/*
243			 * Check against supported rates.
244			 */
245			for (j = 0; j < srs->rs_nrates; j++) {
246				if (r == RV(srs->rs_rates[j]))
247					break;
248			}
249			if (j == srs->rs_nrates) {
250				if (nrs->rs_rates[i] & IEEE80211_RATE_BASIC)
251					error++;
252				ignore++;
253			}
254		}
255		if (flags & IEEE80211_F_DODEL) {
256			/*
257			 * Delete unacceptable rates.
258			 */
259			if (ignore) {
260				nrs->rs_nrates--;
261				for (j = i; j < nrs->rs_nrates; j++)
262					nrs->rs_rates[j] = nrs->rs_rates[j + 1];
263				nrs->rs_rates[j] = 0;
264				continue;
265			}
266		}
267		if (!ignore)
268			okrate = nrs->rs_rates[i];
269		i++;
270	}
271	if (okrate == 0 || error != 0)
272		return badrate | IEEE80211_RATE_BASIC;
273	else
274		return RV(okrate);
275#undef RV
276}
277
278int
279ieee80211_new_state(struct ifnet *ifp, enum ieee80211_state nstate, int mgt)
280{
281	struct ieee80211com *ic = (void *)ifp;
282	struct ieee80211_node *ni;
283	int error, ostate;
284#ifdef IEEE80211_DEBUG
285	static const char *stname[] =
286	    { "INIT", "SCAN", "AUTH", "ASSOC", "RUN" };
287#endif
288
289	ostate = ic->ic_state;
290	IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
291		stname[ostate], stname[nstate]));
292	if (ic->ic_newstate) {
293		error = (*ic->ic_newstate)(ic->ic_softc, nstate);
294		if (error == EINPROGRESS)
295			return 0;
296		if (error != 0)
297			return error;
298	}
299
300	/* state transition */
301	ic->ic_state = nstate;
302	ni = ic->ic_bss;			/* NB: no reference held */
303	switch (nstate) {
304	case IEEE80211_S_INIT:
305		switch (ostate) {
306		case IEEE80211_S_INIT:
307			break;
308		case IEEE80211_S_RUN:
309			switch (ic->ic_opmode) {
310			case IEEE80211_M_STA:
311				IEEE80211_SEND_MGMT(ic, ni,
312				    IEEE80211_FC0_SUBTYPE_DISASSOC,
313				    IEEE80211_REASON_ASSOC_LEAVE);
314				break;
315			case IEEE80211_M_HOSTAP:
316				mtx_lock(&ic->ic_nodelock);
317				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
318					if (ni->ni_associd == 0)
319						continue;
320					IEEE80211_SEND_MGMT(ic, ni,
321					    IEEE80211_FC0_SUBTYPE_DISASSOC,
322					    IEEE80211_REASON_ASSOC_LEAVE);
323				}
324				mtx_unlock(&ic->ic_nodelock);
325				break;
326			default:
327				break;
328			}
329			/* FALLTHRU */
330		case IEEE80211_S_ASSOC:
331			switch (ic->ic_opmode) {
332			case IEEE80211_M_STA:
333				IEEE80211_SEND_MGMT(ic, ni,
334				    IEEE80211_FC0_SUBTYPE_DEAUTH,
335				    IEEE80211_REASON_AUTH_LEAVE);
336				break;
337			case IEEE80211_M_HOSTAP:
338				mtx_lock(&ic->ic_nodelock);
339				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
340					IEEE80211_SEND_MGMT(ic, ni,
341					    IEEE80211_FC0_SUBTYPE_DEAUTH,
342					    IEEE80211_REASON_AUTH_LEAVE);
343				}
344				mtx_unlock(&ic->ic_nodelock);
345				break;
346			default:
347				break;
348			}
349			/* FALLTHRU */
350		case IEEE80211_S_AUTH:
351		case IEEE80211_S_SCAN:
352			ic->ic_mgt_timer = 0;
353			IF_DRAIN(&ic->ic_mgtq);
354			if (ic->ic_wep_ctx != NULL) {
355				free(ic->ic_wep_ctx, M_DEVBUF);
356				ic->ic_wep_ctx = NULL;
357			}
358			ieee80211_free_allnodes(ic);
359			break;
360		}
361		break;
362	case IEEE80211_S_SCAN:
363		ic->ic_flags &= ~IEEE80211_F_SIBSS;
364		/* initialize bss for probe request */
365		IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
366		IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
367		ni->ni_rates = ic->ic_sup_rates[
368			ieee80211_chan2mode(ic, ni->ni_chan)];
369		ni->ni_associd = 0;
370		ni->ni_rstamp = 0;
371		switch (ostate) {
372		case IEEE80211_S_INIT:
373			if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
374			    ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
375				/*
376				 * AP operation and we already have a channel;
377				 * bypass the scan and startup immediately.
378				 */
379				ieee80211_create_ibss(ic, ic->ic_des_chan);
380			} else {
381				ieee80211_begin_scan(ifp, ni);
382			}
383			break;
384		case IEEE80211_S_SCAN:
385			/* scan next */
386			if (ic->ic_flags & IEEE80211_F_ASCAN) {
387				IEEE80211_SEND_MGMT(ic, ni,
388				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
389			}
390			break;
391		case IEEE80211_S_RUN:
392			/* beacon miss */
393			if (ifp->if_flags & IFF_DEBUG) {
394				/* XXX bssid clobbered above */
395				if_printf(ifp, "no recent beacons from %s;"
396				    " rescanning\n",
397				    ether_sprintf(ic->ic_bss->ni_bssid));
398			}
399			ieee80211_free_allnodes(ic);
400			/* FALLTHRU */
401		case IEEE80211_S_AUTH:
402		case IEEE80211_S_ASSOC:
403			/* timeout restart scan */
404			ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
405			if (ni != NULL) {
406				ni->ni_fails++;
407				ieee80211_unref_node(&ni);
408			}
409			ieee80211_begin_scan(ifp, ic->ic_bss);
410			break;
411		}
412		break;
413	case IEEE80211_S_AUTH:
414		switch (ostate) {
415		case IEEE80211_S_INIT:
416			IEEE80211_DPRINTF(("%s: invalid transition\n",
417				__func__));
418			break;
419		case IEEE80211_S_SCAN:
420			IEEE80211_SEND_MGMT(ic, ni,
421			    IEEE80211_FC0_SUBTYPE_AUTH, 1);
422			break;
423		case IEEE80211_S_AUTH:
424		case IEEE80211_S_ASSOC:
425			switch (mgt) {
426			case IEEE80211_FC0_SUBTYPE_AUTH:
427				/* ??? */
428				IEEE80211_SEND_MGMT(ic, ni,
429				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
430				break;
431			case IEEE80211_FC0_SUBTYPE_DEAUTH:
432				/* ignore and retry scan on timeout */
433				break;
434			}
435			break;
436		case IEEE80211_S_RUN:
437			switch (mgt) {
438			case IEEE80211_FC0_SUBTYPE_AUTH:
439				IEEE80211_SEND_MGMT(ic, ni,
440				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
441				ic->ic_state = ostate;	/* stay RUN */
442				break;
443			case IEEE80211_FC0_SUBTYPE_DEAUTH:
444				/* try to reauth */
445				IEEE80211_SEND_MGMT(ic, ni,
446				    IEEE80211_FC0_SUBTYPE_AUTH, 1);
447				break;
448			}
449			break;
450		}
451		break;
452	case IEEE80211_S_ASSOC:
453		switch (ostate) {
454		case IEEE80211_S_INIT:
455		case IEEE80211_S_SCAN:
456		case IEEE80211_S_ASSOC:
457			IEEE80211_DPRINTF(("%s: invalid transition\n",
458				__func__));
459			break;
460		case IEEE80211_S_AUTH:
461			IEEE80211_SEND_MGMT(ic, ni,
462			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
463			break;
464		case IEEE80211_S_RUN:
465			IEEE80211_SEND_MGMT(ic, ni,
466			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
467			break;
468		}
469		break;
470	case IEEE80211_S_RUN:
471		switch (ostate) {
472		case IEEE80211_S_INIT:
473		case IEEE80211_S_AUTH:
474		case IEEE80211_S_RUN:
475			IEEE80211_DPRINTF(("%s: invalid transition\n",
476				__func__));
477			break;
478		case IEEE80211_S_SCAN:		/* adhoc/hostap mode */
479		case IEEE80211_S_ASSOC:		/* infra mode */
480			KASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
481				("%s: bogus xmit rate %u setup\n", __func__,
482					ni->ni_txrate));
483			if (ifp->if_flags & IFF_DEBUG) {
484				if_printf(ifp, " ");
485				if (ic->ic_opmode == IEEE80211_M_STA)
486					printf("associated ");
487				else
488					printf("synchronized ");
489				printf("with %s ssid ",
490				    ether_sprintf(ni->ni_bssid));
491				ieee80211_print_essid(ic->ic_bss->ni_essid,
492				    ni->ni_esslen);
493				printf(" channel %d start %uMb\n",
494					ieee80211_chan2ieee(ic, ni->ni_chan),
495					IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
496			}
497			ic->ic_mgt_timer = 0;
498			(*ifp->if_start)(ifp);
499			break;
500		}
501		break;
502	}
503	return 0;
504}
505