ieee80211_proto.c revision 116742 
1/*-
2 * Copyright (c) 2002, 2003 Sam Leffler, Errno Consulting
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer,
10 *    without modification.
11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
12 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
13 *    redistribution must be conditioned upon including a substantially
14 *    similar Disclaimer requirement for further binary redistribution.
15 * 3. Neither the names of the above-listed copyright holders nor the names
16 *    of any contributors may be used to endorse or promote products derived
17 *    from this software without specific prior written permission.
18 *
19 * Alternatively, this software may be distributed under the terms of the
20 * GNU General Public License ("GPL") version 2 as published by the Free
21 * Software Foundation.
22 *
23 * NO WARRANTY
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
27 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
28 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
29 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
32 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
34 * THE POSSIBILITY OF SUCH DAMAGES.
35 */
36
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_proto.c 116742 2003-06-23 16:55:01Z sam $");
39
40/*
41 * IEEE 802.11 protocol support.
42 */
43
44#include "opt_inet.h"
45
46#include <sys/param.h>
47#include <sys/systm.h>
48#include <sys/mbuf.h>
49#include <sys/malloc.h>
50#include <sys/kernel.h>
51#include <sys/socket.h>
52#include <sys/sockio.h>
53#include <sys/endian.h>
54#include <sys/errno.h>
55#include <sys/bus.h>
56#include <sys/proc.h>
57#include <sys/sysctl.h>
58
59#include <machine/atomic.h>
60
61#include <net/if.h>
62#include <net/if_dl.h>
63#include <net/if_media.h>
64#include <net/if_arp.h>
65#include <net/ethernet.h>
66#include <net/if_llc.h>
67
68#include <net80211/ieee80211_var.h>
69
70#include <net/bpf.h>
71
72#ifdef INET
73#include <netinet/in.h>
74#include <netinet/if_ether.h>
75#endif
76
77#define	IEEE80211_RATE2MBS(r)	(((r) & IEEE80211_RATE_VAL) / 2)
78
79const char *ieee80211_mgt_subtype_name[] = {
80	"assoc_req",	"assoc_resp",	"reassoc_req",	"reassoc_resp",
81	"probe_req",	"probe_resp",	"reserved#6",	"reserved#7",
82	"beacon",	"atim",		"disassoc",	"auth",
83	"deauth",	"reserved#13",	"reserved#14",	"reserved#15"
84};
85
86void
87ieee80211_proto_attach(struct ifnet *ifp)
88{
89	struct ieee80211com *ic = (void *)ifp;
90
91	ifp->if_hdrlen = sizeof(struct ieee80211_frame);
92
93#ifdef notdef
94	ic->ic_rtsthreshold = IEEE80211_RTS_DEFAULT;
95#else
96	ic->ic_rtsthreshold = IEEE80211_RTS_MAX;
97#endif
98	ic->ic_fragthreshold = 2346;		/* XXX not used yet */
99	ic->ic_fixed_rate = -1;			/* no fixed rate */
100
101	mtx_init(&ic->ic_mgtq.ifq_mtx, ifp->if_name, "mgmt send q", MTX_DEF);
102
103	/* initialize management frame handlers */
104	ic->ic_recv_mgmt = ieee80211_recv_mgmt;
105	ic->ic_send_mgmt = ieee80211_send_mgmt;
106}
107
108void
109ieee80211_proto_detach(struct ifnet *ifp)
110{
111	struct ieee80211com *ic = (void *)ifp;
112
113	IF_DRAIN(&ic->ic_mgtq);
114	mtx_destroy(&ic->ic_mgtq.ifq_mtx);
115}
116
117void
118ieee80211_print_essid(u_int8_t *essid, int len)
119{
120	int i;
121	u_int8_t *p;
122
123	if (len > IEEE80211_NWID_LEN)
124		len = IEEE80211_NWID_LEN;
125	/* determine printable or not */
126	for (i = 0, p = essid; i < len; i++, p++) {
127		if (*p < ' ' || *p > 0x7e)
128			break;
129	}
130	if (i == len) {
131		printf("\"");
132		for (i = 0, p = essid; i < len; i++, p++)
133			printf("%c", *p);
134		printf("\"");
135	} else {
136		printf("0x");
137		for (i = 0, p = essid; i < len; i++, p++)
138			printf("%02x", *p);
139	}
140}
141
142void
143ieee80211_dump_pkt(u_int8_t *buf, int len, int rate, int rssi)
144{
145	struct ieee80211_frame *wh;
146	int i;
147
148	wh = (struct ieee80211_frame *)buf;
149	switch (wh->i_fc[1] & IEEE80211_FC1_DIR_MASK) {
150	case IEEE80211_FC1_DIR_NODS:
151		printf("NODS %s", ether_sprintf(wh->i_addr2));
152		printf("->%s", ether_sprintf(wh->i_addr1));
153		printf("(%s)", ether_sprintf(wh->i_addr3));
154		break;
155	case IEEE80211_FC1_DIR_TODS:
156		printf("TODS %s", ether_sprintf(wh->i_addr2));
157		printf("->%s", ether_sprintf(wh->i_addr3));
158		printf("(%s)", ether_sprintf(wh->i_addr1));
159		break;
160	case IEEE80211_FC1_DIR_FROMDS:
161		printf("FRDS %s", ether_sprintf(wh->i_addr3));
162		printf("->%s", ether_sprintf(wh->i_addr1));
163		printf("(%s)", ether_sprintf(wh->i_addr2));
164		break;
165	case IEEE80211_FC1_DIR_DSTODS:
166		printf("DSDS %s", ether_sprintf((u_int8_t *)&wh[1]));
167		printf("->%s", ether_sprintf(wh->i_addr3));
168		printf("(%s", ether_sprintf(wh->i_addr2));
169		printf("->%s)", ether_sprintf(wh->i_addr1));
170		break;
171	}
172	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
173	case IEEE80211_FC0_TYPE_DATA:
174		printf(" data");
175		break;
176	case IEEE80211_FC0_TYPE_MGT:
177		printf(" %s", ieee80211_mgt_subtype_name[
178		    (wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK)
179		    >> IEEE80211_FC0_SUBTYPE_SHIFT]);
180		break;
181	default:
182		printf(" type#%d", wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK);
183		break;
184	}
185	if (wh->i_fc[1] & IEEE80211_FC1_WEP)
186		printf(" WEP");
187	if (rate >= 0)
188		printf(" %dM", rate / 2);
189	if (rssi >= 0)
190		printf(" +%d", rssi);
191	printf("\n");
192	if (len > 0) {
193		for (i = 0; i < len; i++) {
194			if ((i & 1) == 0)
195				printf(" ");
196			printf("%02x", buf[i]);
197		}
198		printf("\n");
199	}
200}
201
202int
203ieee80211_fix_rate(struct ieee80211com *ic, struct ieee80211_node *ni, int flags)
204{
205#define	RV(v)	((v) & IEEE80211_RATE_VAL)
206	int i, j, ignore, error;
207	int okrate, badrate;
208	struct ieee80211_rateset *srs, *nrs;
209	u_int8_t r;
210
211	error = 0;
212	okrate = badrate = 0;
213	srs = &ic->ic_sup_rates[ieee80211_chan2mode(ic, ni->ni_chan)];
214	nrs = &ni->ni_rates;
215	for (i = 0; i < ni->ni_rates.rs_nrates; ) {
216		ignore = 0;
217		if (flags & IEEE80211_F_DOSORT) {
218			/*
219			 * Sort rates.
220			 */
221			for (j = i + 1; j < nrs->rs_nrates; j++) {
222				if (RV(nrs->rs_rates[i]) > RV(nrs->rs_rates[j])) {
223					r = nrs->rs_rates[i];
224					nrs->rs_rates[i] = nrs->rs_rates[j];
225					nrs->rs_rates[j] = r;
226				}
227			}
228		}
229		r = nrs->rs_rates[i] & IEEE80211_RATE_VAL;
230		badrate = r;
231		if (flags & IEEE80211_F_DOFRATE) {
232			/*
233			 * Apply fixed rate constraint.  Note that we do
234			 * not apply the constraint to basic rates as
235			 * otherwise we may not be able to associate if
236			 * the rate set we submit to the AP is invalid
237			 * (e.g. fix rate at 36Mb/s which is not a basic
238			 * rate for 11a operation).
239			 */
240			if ((nrs->rs_rates[i] & IEEE80211_RATE_BASIC) == 0 &&
241			    ic->ic_fixed_rate >= 0 &&
242			    r != RV(srs->rs_rates[ic->ic_fixed_rate]))
243				ignore++;
244		}
245		if (flags & IEEE80211_F_DONEGO) {
246			/*
247			 * Check against supported rates.
248			 */
249			for (j = 0; j < srs->rs_nrates; j++) {
250				if (r == RV(srs->rs_rates[j]))
251					break;
252			}
253			if (j == srs->rs_nrates) {
254				if (nrs->rs_rates[i] & IEEE80211_RATE_BASIC)
255					error++;
256				ignore++;
257			}
258		}
259		if (flags & IEEE80211_F_DODEL) {
260			/*
261			 * Delete unacceptable rates.
262			 */
263			if (ignore) {
264				nrs->rs_nrates--;
265				for (j = i; j < nrs->rs_nrates; j++)
266					nrs->rs_rates[j] = nrs->rs_rates[j + 1];
267				nrs->rs_rates[j] = 0;
268				continue;
269			}
270		}
271		if (!ignore)
272			okrate = nrs->rs_rates[i];
273		i++;
274	}
275	if (okrate == 0 || error != 0)
276		return badrate | IEEE80211_RATE_BASIC;
277	else
278		return RV(okrate);
279#undef RV
280}
281
282int
283ieee80211_new_state(struct ifnet *ifp, enum ieee80211_state nstate, int mgt)
284{
285	struct ieee80211com *ic = (void *)ifp;
286	struct ieee80211_node *ni;
287	int error, ostate;
288#ifdef IEEE80211_DEBUG
289	static const char *stname[] =
290	    { "INIT", "SCAN", "AUTH", "ASSOC", "RUN" };
291#endif
292
293	ostate = ic->ic_state;
294	IEEE80211_DPRINTF(("%s: %s -> %s\n", __func__,
295		stname[ostate], stname[nstate]));
296	if (ic->ic_newstate) {
297		error = (*ic->ic_newstate)(ic->ic_softc, nstate);
298		if (error == EINPROGRESS)
299			return 0;
300		if (error != 0)
301			return error;
302	}
303
304	/* state transition */
305	ic->ic_state = nstate;
306	ni = ic->ic_bss;			/* NB: no reference held */
307	switch (nstate) {
308	case IEEE80211_S_INIT:
309		switch (ostate) {
310		case IEEE80211_S_INIT:
311			break;
312		case IEEE80211_S_RUN:
313			switch (ic->ic_opmode) {
314			case IEEE80211_M_STA:
315				IEEE80211_SEND_MGMT(ic, ni,
316				    IEEE80211_FC0_SUBTYPE_DISASSOC,
317				    IEEE80211_REASON_ASSOC_LEAVE);
318				break;
319			case IEEE80211_M_HOSTAP:
320				mtx_lock(&ic->ic_nodelock);
321				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
322					if (ni->ni_associd == 0)
323						continue;
324					IEEE80211_SEND_MGMT(ic, ni,
325					    IEEE80211_FC0_SUBTYPE_DISASSOC,
326					    IEEE80211_REASON_ASSOC_LEAVE);
327				}
328				mtx_unlock(&ic->ic_nodelock);
329				break;
330			default:
331				break;
332			}
333			/* FALLTHRU */
334		case IEEE80211_S_ASSOC:
335			switch (ic->ic_opmode) {
336			case IEEE80211_M_STA:
337				IEEE80211_SEND_MGMT(ic, ni,
338				    IEEE80211_FC0_SUBTYPE_DEAUTH,
339				    IEEE80211_REASON_AUTH_LEAVE);
340				break;
341			case IEEE80211_M_HOSTAP:
342				mtx_lock(&ic->ic_nodelock);
343				TAILQ_FOREACH(ni, &ic->ic_node, ni_list) {
344					IEEE80211_SEND_MGMT(ic, ni,
345					    IEEE80211_FC0_SUBTYPE_DEAUTH,
346					    IEEE80211_REASON_AUTH_LEAVE);
347				}
348				mtx_unlock(&ic->ic_nodelock);
349				break;
350			default:
351				break;
352			}
353			/* FALLTHRU */
354		case IEEE80211_S_AUTH:
355		case IEEE80211_S_SCAN:
356			ic->ic_mgt_timer = 0;
357			IF_DRAIN(&ic->ic_mgtq);
358			if (ic->ic_wep_ctx != NULL) {
359				free(ic->ic_wep_ctx, M_DEVBUF);
360				ic->ic_wep_ctx = NULL;
361			}
362			ieee80211_free_allnodes(ic);
363			break;
364		}
365		break;
366	case IEEE80211_S_SCAN:
367		ic->ic_flags &= ~IEEE80211_F_SIBSS;
368		/* initialize bss for probe request */
369		IEEE80211_ADDR_COPY(ni->ni_macaddr, ifp->if_broadcastaddr);
370		IEEE80211_ADDR_COPY(ni->ni_bssid, ifp->if_broadcastaddr);
371		ni->ni_rates = ic->ic_sup_rates[
372			ieee80211_chan2mode(ic, ni->ni_chan)];
373		ni->ni_associd = 0;
374		ni->ni_rstamp = 0;
375		switch (ostate) {
376		case IEEE80211_S_INIT:
377			if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
378			    ic->ic_des_chan != IEEE80211_CHAN_ANYC) {
379				/*
380				 * AP operation and we already have a channel;
381				 * bypass the scan and startup immediately.
382				 */
383				ieee80211_create_ibss(ic, ic->ic_des_chan);
384			} else {
385				ieee80211_begin_scan(ifp, ni);
386			}
387			break;
388		case IEEE80211_S_SCAN:
389			/* scan next */
390			if (ic->ic_flags & IEEE80211_F_ASCAN) {
391				IEEE80211_SEND_MGMT(ic, ni,
392				    IEEE80211_FC0_SUBTYPE_PROBE_REQ, 0);
393			}
394			break;
395		case IEEE80211_S_RUN:
396			/* beacon miss */
397			if (ifp->if_flags & IFF_DEBUG) {
398				/* XXX bssid clobbered above */
399				if_printf(ifp, "no recent beacons from %s;"
400				    " rescanning\n",
401				    ether_sprintf(ic->ic_bss->ni_bssid));
402			}
403			ieee80211_free_allnodes(ic);
404			/* FALLTHRU */
405		case IEEE80211_S_AUTH:
406		case IEEE80211_S_ASSOC:
407			/* timeout restart scan */
408			ni = ieee80211_find_node(ic, ic->ic_bss->ni_macaddr);
409			if (ni != NULL) {
410				ni->ni_fails++;
411				ieee80211_unref_node(&ni);
412			}
413			ieee80211_begin_scan(ifp, ic->ic_bss);
414			break;
415		}
416		break;
417	case IEEE80211_S_AUTH:
418		switch (ostate) {
419		case IEEE80211_S_INIT:
420			IEEE80211_DPRINTF(("%s: invalid transition\n",
421				__func__));
422			break;
423		case IEEE80211_S_SCAN:
424			IEEE80211_SEND_MGMT(ic, ni,
425			    IEEE80211_FC0_SUBTYPE_AUTH, 1);
426			break;
427		case IEEE80211_S_AUTH:
428		case IEEE80211_S_ASSOC:
429			switch (mgt) {
430			case IEEE80211_FC0_SUBTYPE_AUTH:
431				/* ??? */
432				IEEE80211_SEND_MGMT(ic, ni,
433				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
434				break;
435			case IEEE80211_FC0_SUBTYPE_DEAUTH:
436				/* ignore and retry scan on timeout */
437				break;
438			}
439			break;
440		case IEEE80211_S_RUN:
441			switch (mgt) {
442			case IEEE80211_FC0_SUBTYPE_AUTH:
443				IEEE80211_SEND_MGMT(ic, ni,
444				    IEEE80211_FC0_SUBTYPE_AUTH, 2);
445				ic->ic_state = ostate;	/* stay RUN */
446				break;
447			case IEEE80211_FC0_SUBTYPE_DEAUTH:
448				/* try to reauth */
449				IEEE80211_SEND_MGMT(ic, ni,
450				    IEEE80211_FC0_SUBTYPE_AUTH, 1);
451				break;
452			}
453			break;
454		}
455		break;
456	case IEEE80211_S_ASSOC:
457		switch (ostate) {
458		case IEEE80211_S_INIT:
459		case IEEE80211_S_SCAN:
460		case IEEE80211_S_ASSOC:
461			IEEE80211_DPRINTF(("%s: invalid transition\n",
462				__func__));
463			break;
464		case IEEE80211_S_AUTH:
465			IEEE80211_SEND_MGMT(ic, ni,
466			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 0);
467			break;
468		case IEEE80211_S_RUN:
469			IEEE80211_SEND_MGMT(ic, ni,
470			    IEEE80211_FC0_SUBTYPE_ASSOC_REQ, 1);
471			break;
472		}
473		break;
474	case IEEE80211_S_RUN:
475		switch (ostate) {
476		case IEEE80211_S_INIT:
477		case IEEE80211_S_AUTH:
478		case IEEE80211_S_RUN:
479			IEEE80211_DPRINTF(("%s: invalid transition\n",
480				__func__));
481			break;
482		case IEEE80211_S_SCAN:		/* adhoc/hostap mode */
483		case IEEE80211_S_ASSOC:		/* infra mode */
484			KASSERT(ni->ni_txrate < ni->ni_rates.rs_nrates,
485				("%s: bogus xmit rate %u setup\n", __func__,
486					ni->ni_txrate));
487			if (ifp->if_flags & IFF_DEBUG) {
488				if_printf(ifp, " ");
489				if (ic->ic_opmode == IEEE80211_M_STA)
490					printf("associated ");
491				else
492					printf("synchronized ");
493				printf("with %s ssid ",
494				    ether_sprintf(ni->ni_bssid));
495				ieee80211_print_essid(ic->ic_bss->ni_essid,
496				    ni->ni_esslen);
497				printf(" channel %d start %uMb\n",
498					ieee80211_chan2ieee(ic, ni->ni_chan),
499					IEEE80211_RATE2MBS(ni->ni_rates.rs_rates[ni->ni_txrate]));
500			}
501			ic->ic_mgt_timer = 0;
502			(*ifp->if_start)(ifp);
503			break;
504		}
505		break;
506	}
507	return 0;
508}
509