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ieee80211_scan_sta.c (184205) ieee80211_scan_sta.c (184210)
1/*-
2 * Copyright (c) 2002-2008 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 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
1/*-
2 * Copyright (c) 2002-2008 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 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#include <sys/cdefs.h>
27__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_scan_sta.c 184205 2008-10-23 15:53:51Z des $");
27__FBSDID("$FreeBSD: head/sys/net80211/ieee80211_scan_sta.c 184210 2008-10-23 19:57:13Z des $");
28
29/*
30 * IEEE 802.11 station scanning support.
31 */
32#include "opt_wlan.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/module.h>
38
39#include <sys/socket.h>
40
41#include <net/if.h>
42#include <net/if_media.h>
43#include <net/ethernet.h>
44
45#include <net80211/ieee80211_var.h>
46#include <net80211/ieee80211_input.h>
47#include <net80211/ieee80211_regdomain.h>
48
49#include <net/bpf.h>
50
51/*
52 * Parameters for managing cache entries:
53 *
54 * o a station with STA_FAILS_MAX failures is not considered
55 * when picking a candidate
56 * o a station that hasn't had an update in STA_PURGE_SCANS
57 * (background) scans is discarded
58 * o after STA_FAILS_AGE seconds we clear the failure count
59 */
60#define STA_FAILS_MAX 2 /* assoc failures before ignored */
61#define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */
62#define STA_PURGE_SCANS 2 /* age for purging entries (scans) */
63
64/* XXX tunable */
65#define STA_RSSI_MIN 8 /* min acceptable rssi */
66#define STA_RSSI_MAX 40 /* max rssi for comparison */
67
68struct sta_entry {
69 struct ieee80211_scan_entry base;
70 TAILQ_ENTRY(sta_entry) se_list;
71 LIST_ENTRY(sta_entry) se_hash;
72 uint8_t se_fails; /* failure to associate count */
73 uint8_t se_seen; /* seen during current scan */
74 uint8_t se_notseen; /* not seen in previous scans */
75 uint8_t se_flags;
76#define STA_SSID_MATCH 0x01
77#define STA_BSSID_MATCH 0x02
78 uint32_t se_avgrssi; /* LPF rssi state */
79 unsigned long se_lastupdate; /* time of last update */
80 unsigned long se_lastfail; /* time of last failure */
81 unsigned long se_lastassoc; /* time of last association */
82 u_int se_scangen; /* iterator scan gen# */
83 u_int se_countrygen; /* gen# of last cc notify */
84};
85
86#define STA_HASHSIZE 32
87/* simple hash is enough for variation of macaddr */
88#define STA_HASH(addr) \
89 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE)
90
91struct sta_table {
92 struct mtx st_lock; /* on scan table */
93 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */
94 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE];
95 struct mtx st_scanlock; /* on st_scaniter */
96 u_int st_scaniter; /* gen# for iterator */
97 u_int st_scangen; /* scan generation # */
98 int st_newscan;
99 /* ap-related state */
100 int st_maxrssi[IEEE80211_CHAN_MAX];
101};
102
103static void sta_flush_table(struct sta_table *);
104/*
105 * match_bss returns a bitmask describing if an entry is suitable
106 * for use. If non-zero the entry was deemed not suitable and it's
107 * contents explains why. The following flags are or'd to to this
108 * mask and can be used to figure out why the entry was rejected.
109 */
110#define MATCH_CHANNEL 0x001 /* channel mismatch */
111#define MATCH_CAPINFO 0x002 /* capabilities mismatch, e.g. no ess */
112#define MATCH_PRIVACY 0x004 /* privacy mismatch */
113#define MATCH_RATE 0x008 /* rate set mismatch */
114#define MATCH_SSID 0x010 /* ssid mismatch */
115#define MATCH_BSSID 0x020 /* bssid mismatch */
116#define MATCH_FAILS 0x040 /* too many failed auth attempts */
117#define MATCH_NOTSEEN 0x080 /* not seen in recent scans */
118#define MATCH_RSSI 0x100 /* rssi deemed too low to use */
119#define MATCH_CC 0x200 /* country code mismatch */
120static int match_bss(struct ieee80211vap *,
121 const struct ieee80211_scan_state *, struct sta_entry *, int);
122static void adhoc_age(struct ieee80211_scan_state *);
123
124static __inline int
125isocmp(const uint8_t cc1[], const uint8_t cc2[])
126{
127 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]);
128}
129
130/* number of references from net80211 layer */
131static int nrefs = 0;
132
133/*
134 * Attach prior to any scanning work.
135 */
136static int
137sta_attach(struct ieee80211_scan_state *ss)
138{
139 struct sta_table *st;
140
28
29/*
30 * IEEE 802.11 station scanning support.
31 */
32#include "opt_wlan.h"
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/module.h>
38
39#include <sys/socket.h>
40
41#include <net/if.h>
42#include <net/if_media.h>
43#include <net/ethernet.h>
44
45#include <net80211/ieee80211_var.h>
46#include <net80211/ieee80211_input.h>
47#include <net80211/ieee80211_regdomain.h>
48
49#include <net/bpf.h>
50
51/*
52 * Parameters for managing cache entries:
53 *
54 * o a station with STA_FAILS_MAX failures is not considered
55 * when picking a candidate
56 * o a station that hasn't had an update in STA_PURGE_SCANS
57 * (background) scans is discarded
58 * o after STA_FAILS_AGE seconds we clear the failure count
59 */
60#define STA_FAILS_MAX 2 /* assoc failures before ignored */
61#define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */
62#define STA_PURGE_SCANS 2 /* age for purging entries (scans) */
63
64/* XXX tunable */
65#define STA_RSSI_MIN 8 /* min acceptable rssi */
66#define STA_RSSI_MAX 40 /* max rssi for comparison */
67
68struct sta_entry {
69 struct ieee80211_scan_entry base;
70 TAILQ_ENTRY(sta_entry) se_list;
71 LIST_ENTRY(sta_entry) se_hash;
72 uint8_t se_fails; /* failure to associate count */
73 uint8_t se_seen; /* seen during current scan */
74 uint8_t se_notseen; /* not seen in previous scans */
75 uint8_t se_flags;
76#define STA_SSID_MATCH 0x01
77#define STA_BSSID_MATCH 0x02
78 uint32_t se_avgrssi; /* LPF rssi state */
79 unsigned long se_lastupdate; /* time of last update */
80 unsigned long se_lastfail; /* time of last failure */
81 unsigned long se_lastassoc; /* time of last association */
82 u_int se_scangen; /* iterator scan gen# */
83 u_int se_countrygen; /* gen# of last cc notify */
84};
85
86#define STA_HASHSIZE 32
87/* simple hash is enough for variation of macaddr */
88#define STA_HASH(addr) \
89 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE)
90
91struct sta_table {
92 struct mtx st_lock; /* on scan table */
93 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */
94 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE];
95 struct mtx st_scanlock; /* on st_scaniter */
96 u_int st_scaniter; /* gen# for iterator */
97 u_int st_scangen; /* scan generation # */
98 int st_newscan;
99 /* ap-related state */
100 int st_maxrssi[IEEE80211_CHAN_MAX];
101};
102
103static void sta_flush_table(struct sta_table *);
104/*
105 * match_bss returns a bitmask describing if an entry is suitable
106 * for use. If non-zero the entry was deemed not suitable and it's
107 * contents explains why. The following flags are or'd to to this
108 * mask and can be used to figure out why the entry was rejected.
109 */
110#define MATCH_CHANNEL 0x001 /* channel mismatch */
111#define MATCH_CAPINFO 0x002 /* capabilities mismatch, e.g. no ess */
112#define MATCH_PRIVACY 0x004 /* privacy mismatch */
113#define MATCH_RATE 0x008 /* rate set mismatch */
114#define MATCH_SSID 0x010 /* ssid mismatch */
115#define MATCH_BSSID 0x020 /* bssid mismatch */
116#define MATCH_FAILS 0x040 /* too many failed auth attempts */
117#define MATCH_NOTSEEN 0x080 /* not seen in recent scans */
118#define MATCH_RSSI 0x100 /* rssi deemed too low to use */
119#define MATCH_CC 0x200 /* country code mismatch */
120static int match_bss(struct ieee80211vap *,
121 const struct ieee80211_scan_state *, struct sta_entry *, int);
122static void adhoc_age(struct ieee80211_scan_state *);
123
124static __inline int
125isocmp(const uint8_t cc1[], const uint8_t cc2[])
126{
127 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]);
128}
129
130/* number of references from net80211 layer */
131static int nrefs = 0;
132
133/*
134 * Attach prior to any scanning work.
135 */
136static int
137sta_attach(struct ieee80211_scan_state *ss)
138{
139 struct sta_table *st;
140
141 st = malloc(sizeof(struct sta_table),
141 MALLOC(st, struct sta_table *, sizeof(struct sta_table),
142 M_80211_SCAN, M_NOWAIT | M_ZERO);
143 if (st == NULL)
144 return 0;
145 mtx_init(&st->st_lock, "scantable", "802.11 scan table", MTX_DEF);
146 mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF);
147 TAILQ_INIT(&st->st_entry);
148 ss->ss_priv = st;
149 nrefs++; /* NB: we assume caller locking */
150 return 1;
151}
152
153/*
154 * Cleanup any private state.
155 */
156static int
157sta_detach(struct ieee80211_scan_state *ss)
158{
159 struct sta_table *st = ss->ss_priv;
160
161 if (st != NULL) {
162 sta_flush_table(st);
163 mtx_destroy(&st->st_lock);
164 mtx_destroy(&st->st_scanlock);
142 M_80211_SCAN, M_NOWAIT | M_ZERO);
143 if (st == NULL)
144 return 0;
145 mtx_init(&st->st_lock, "scantable", "802.11 scan table", MTX_DEF);
146 mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF);
147 TAILQ_INIT(&st->st_entry);
148 ss->ss_priv = st;
149 nrefs++; /* NB: we assume caller locking */
150 return 1;
151}
152
153/*
154 * Cleanup any private state.
155 */
156static int
157sta_detach(struct ieee80211_scan_state *ss)
158{
159 struct sta_table *st = ss->ss_priv;
160
161 if (st != NULL) {
162 sta_flush_table(st);
163 mtx_destroy(&st->st_lock);
164 mtx_destroy(&st->st_scanlock);
165 free(st, M_80211_SCAN);
165 FREE(st, M_80211_SCAN);
166 KASSERT(nrefs > 0, ("imbalanced attach/detach"));
167 nrefs--; /* NB: we assume caller locking */
168 }
169 return 1;
170}
171
172/*
173 * Flush all per-scan state.
174 */
175static int
176sta_flush(struct ieee80211_scan_state *ss)
177{
178 struct sta_table *st = ss->ss_priv;
179
180 mtx_lock(&st->st_lock);
181 sta_flush_table(st);
182 mtx_unlock(&st->st_lock);
183 ss->ss_last = 0;
184 return 0;
185}
186
187/*
188 * Flush all entries in the scan cache.
189 */
190static void
191sta_flush_table(struct sta_table *st)
192{
193 struct sta_entry *se, *next;
194
195 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) {
196 TAILQ_REMOVE(&st->st_entry, se, se_list);
197 LIST_REMOVE(se, se_hash);
198 ieee80211_ies_cleanup(&se->base.se_ies);
166 KASSERT(nrefs > 0, ("imbalanced attach/detach"));
167 nrefs--; /* NB: we assume caller locking */
168 }
169 return 1;
170}
171
172/*
173 * Flush all per-scan state.
174 */
175static int
176sta_flush(struct ieee80211_scan_state *ss)
177{
178 struct sta_table *st = ss->ss_priv;
179
180 mtx_lock(&st->st_lock);
181 sta_flush_table(st);
182 mtx_unlock(&st->st_lock);
183 ss->ss_last = 0;
184 return 0;
185}
186
187/*
188 * Flush all entries in the scan cache.
189 */
190static void
191sta_flush_table(struct sta_table *st)
192{
193 struct sta_entry *se, *next;
194
195 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) {
196 TAILQ_REMOVE(&st->st_entry, se, se_list);
197 LIST_REMOVE(se, se_hash);
198 ieee80211_ies_cleanup(&se->base.se_ies);
199 free(se, M_80211_SCAN);
199 FREE(se, M_80211_SCAN);
200 }
201 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi));
202}
203
204/*
205 * Process a beacon or probe response frame; create an
206 * entry in the scan cache or update any previous entry.
207 */
208static int
209sta_add(struct ieee80211_scan_state *ss,
210 const struct ieee80211_scanparams *sp,
211 const struct ieee80211_frame *wh,
212 int subtype, int rssi, int noise, int rstamp)
213{
214#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
215#define PICK1ST(_ss) \
216 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \
217 IEEE80211_SCAN_PICK1ST)
218 struct sta_table *st = ss->ss_priv;
219 const uint8_t *macaddr = wh->i_addr2;
220 struct ieee80211vap *vap = ss->ss_vap;
221 struct ieee80211com *ic = vap->iv_ic;
222 struct sta_entry *se;
223 struct ieee80211_scan_entry *ise;
224 int hash;
225
226 hash = STA_HASH(macaddr);
227
228 mtx_lock(&st->st_lock);
229 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
230 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
231 goto found;
200 }
201 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi));
202}
203
204/*
205 * Process a beacon or probe response frame; create an
206 * entry in the scan cache or update any previous entry.
207 */
208static int
209sta_add(struct ieee80211_scan_state *ss,
210 const struct ieee80211_scanparams *sp,
211 const struct ieee80211_frame *wh,
212 int subtype, int rssi, int noise, int rstamp)
213{
214#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
215#define PICK1ST(_ss) \
216 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \
217 IEEE80211_SCAN_PICK1ST)
218 struct sta_table *st = ss->ss_priv;
219 const uint8_t *macaddr = wh->i_addr2;
220 struct ieee80211vap *vap = ss->ss_vap;
221 struct ieee80211com *ic = vap->iv_ic;
222 struct sta_entry *se;
223 struct ieee80211_scan_entry *ise;
224 int hash;
225
226 hash = STA_HASH(macaddr);
227
228 mtx_lock(&st->st_lock);
229 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
230 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
231 goto found;
232 se = malloc(sizeof(struct sta_entry),
232 MALLOC(se, struct sta_entry *, sizeof(struct sta_entry),
233 M_80211_SCAN, M_NOWAIT | M_ZERO);
234 if (se == NULL) {
235 mtx_unlock(&st->st_lock);
236 return 0;
237 }
238 se->se_scangen = st->st_scaniter-1;
239 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER;
240 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr);
241 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list);
242 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash);
243found:
244 ise = &se->base;
245 /* XXX ap beaconing multiple ssid w/ same bssid */
246 if (sp->ssid[1] != 0 &&
247 (ISPROBE(subtype) || ise->se_ssid[1] == 0))
248 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]);
249 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE,
250 ("rate set too large: %u", sp->rates[1]));
251 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]);
252 if (sp->xrates != NULL) {
253 /* XXX validate xrates[1] */
254 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE,
255 ("xrate set too large: %u", sp->xrates[1]));
256 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]);
257 } else
258 ise->se_xrates[1] = 0;
259 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3);
260 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) {
261 /*
262 * Record rssi data using extended precision LPF filter.
263 *
264 * NB: use only on-channel data to insure we get a good
265 * estimate of the signal we'll see when associated.
266 */
267 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi);
268 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi);
269 ise->se_noise = noise;
270 }
271 ise->se_rstamp = rstamp;
272 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp));
273 ise->se_intval = sp->bintval;
274 ise->se_capinfo = sp->capinfo;
275 /*
276 * Beware of overriding se_chan for frames seen
277 * off-channel; this can cause us to attempt an
278 * association on the wrong channel.
279 */
280 if (sp->status & IEEE80211_BPARSE_OFFCHAN) {
281 struct ieee80211_channel *c;
282 /*
283 * Off-channel, locate the home/bss channel for the sta
284 * using the value broadcast in the DSPARMS ie. We know
285 * sp->chan has this value because it's used to calculate
286 * IEEE80211_BPARSE_OFFCHAN.
287 */
288 c = ieee80211_find_channel_byieee(ic, sp->chan,
289 ic->ic_curchan->ic_flags);
290 if (c != NULL) {
291 ise->se_chan = c;
292 } else if (ise->se_chan == NULL) {
293 /* should not happen, pick something */
294 ise->se_chan = ic->ic_curchan;
295 }
296 } else
297 ise->se_chan = ic->ic_curchan;
298 ise->se_fhdwell = sp->fhdwell;
299 ise->se_fhindex = sp->fhindex;
300 ise->se_erp = sp->erp;
301 ise->se_timoff = sp->timoff;
302 if (sp->tim != NULL) {
303 const struct ieee80211_tim_ie *tim =
304 (const struct ieee80211_tim_ie *) sp->tim;
305 ise->se_dtimperiod = tim->tim_period;
306 }
307 if (sp->country != NULL) {
308 const struct ieee80211_country_ie *cie =
309 (const struct ieee80211_country_ie *) sp->country;
310 /*
311 * If 11d is enabled and we're attempting to join a bss
312 * that advertises it's country code then compare our
313 * current settings to what we fetched from the country ie.
314 * If our country code is unspecified or different then
315 * dispatch an event to user space that identifies the
316 * country code so our regdomain config can be changed.
317 */
318 /* XXX only for STA mode? */
319 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) ||
320 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
321 (ic->ic_regdomain.country == CTRY_DEFAULT ||
322 !isocmp(cie->cc, ic->ic_regdomain.isocc))) {
323 /* only issue one notify event per scan */
324 if (se->se_countrygen != st->st_scangen) {
325 ieee80211_notify_country(vap, ise->se_bssid,
326 cie->cc);
327 se->se_countrygen = st->st_scangen;
328 }
329 }
330 ise->se_cc[0] = cie->cc[0];
331 ise->se_cc[1] = cie->cc[1];
332 }
333 /* NB: no need to setup ie ptrs; they are not (currently) used */
334 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len);
335
336 /* clear failure count after STA_FAIL_AGE passes */
337 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) {
338 se->se_fails = 0;
339 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr,
340 "%s: fails %u", __func__, se->se_fails);
341 }
342
343 se->se_lastupdate = ticks; /* update time */
344 se->se_seen = 1;
345 se->se_notseen = 0;
346
347 if (rssi > st->st_maxrssi[sp->bchan])
348 st->st_maxrssi[sp->bchan] = rssi;
349
350 mtx_unlock(&st->st_lock);
351
352 /*
353 * If looking for a quick choice and nothing's
354 * been found check here.
355 */
356 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0)
357 ss->ss_flags |= IEEE80211_SCAN_GOTPICK;
358
359 return 1;
360#undef PICK1ST
361#undef ISPROBE
362}
363
364/*
365 * Check if a channel is excluded by user request.
366 */
367static int
368isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c)
369{
370 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) ||
371 (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
372 c->ic_freq != vap->iv_des_chan->ic_freq));
373}
374
375static struct ieee80211_channel *
376find11gchannel(struct ieee80211com *ic, int i, int freq)
377{
378 struct ieee80211_channel *c;
379 int j;
380
381 /*
382 * The normal ordering in the channel list is b channel
383 * immediately followed by g so optimize the search for
384 * this. We'll still do a full search just in case.
385 */
386 for (j = i+1; j < ic->ic_nchans; j++) {
387 c = &ic->ic_channels[j];
388 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c))
389 return c;
390 }
391 for (j = 0; j < i; j++) {
392 c = &ic->ic_channels[j];
393 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c))
394 return c;
395 }
396 return NULL;
397}
398static const u_int chanflags[IEEE80211_MODE_MAX] = {
399 IEEE80211_CHAN_B, /* IEEE80211_MODE_AUTO */
400 IEEE80211_CHAN_A, /* IEEE80211_MODE_11A */
401 IEEE80211_CHAN_B, /* IEEE80211_MODE_11B */
402 IEEE80211_CHAN_G, /* IEEE80211_MODE_11G */
403 IEEE80211_CHAN_FHSS, /* IEEE80211_MODE_FH */
404 IEEE80211_CHAN_A, /* IEEE80211_MODE_TURBO_A (check base channel)*/
405 IEEE80211_CHAN_G, /* IEEE80211_MODE_TURBO_G */
406 IEEE80211_CHAN_ST, /* IEEE80211_MODE_STURBO_A */
407 IEEE80211_CHAN_A, /* IEEE80211_MODE_11NA (check legacy) */
408 IEEE80211_CHAN_G, /* IEEE80211_MODE_11NG (check legacy) */
409};
410
411static void
412add_channels(struct ieee80211vap *vap,
413 struct ieee80211_scan_state *ss,
414 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq)
415{
416#define N(a) (sizeof(a) / sizeof(a[0]))
417 struct ieee80211com *ic = vap->iv_ic;
418 struct ieee80211_channel *c, *cg;
419 u_int modeflags;
420 int i;
421
422 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode));
423 modeflags = chanflags[mode];
424 for (i = 0; i < nfreq; i++) {
425 if (ss->ss_last >= IEEE80211_SCAN_MAX)
426 break;
427
428 c = ieee80211_find_channel(ic, freq[i], modeflags);
429 if (c == NULL || isexcluded(vap, c))
430 continue;
431 if (mode == IEEE80211_MODE_AUTO) {
432 /*
433 * XXX special-case 11b/g channels so we select
434 * the g channel if both are present.
435 */
436 if (IEEE80211_IS_CHAN_B(c) &&
437 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL)
438 c = cg;
439 }
440 ss->ss_chans[ss->ss_last++] = c;
441 }
442#undef N
443}
444
445struct scanlist {
446 uint16_t mode;
447 uint16_t count;
448 const uint16_t *list;
449};
450
451static int
452checktable(const struct scanlist *scan, const struct ieee80211_channel *c)
453{
454 int i;
455
456 for (; scan->list != NULL; scan++) {
457 for (i = 0; i < scan->count; i++)
458 if (scan->list[i] == c->ic_freq)
459 return 1;
460 }
461 return 0;
462}
463
464static void
465sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
466 const struct scanlist table[])
467{
468 struct ieee80211com *ic = vap->iv_ic;
469 struct ieee80211_channel *c;
470 int i;
471
472 for (i = 0; i < ic->ic_nchans; i++) {
473 if (ss->ss_last >= IEEE80211_SCAN_MAX)
474 break;
475
476 c = &ic->ic_channels[i];
477 /*
478 * Ignore dynamic turbo channels; we scan them
479 * in normal mode (i.e. not boosted). Likewise
480 * for HT channels, they get scanned using
481 * legacy rates.
482 */
483 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c))
484 continue;
485
486 /*
487 * If a desired mode was specified, scan only
488 * channels that satisfy that constraint.
489 */
490 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
491 vap->iv_des_mode != ieee80211_chan2mode(c))
492 continue;
493
494 /*
495 * Skip channels excluded by user request.
496 */
497 if (isexcluded(vap, c))
498 continue;
499
500 /*
501 * Add the channel unless it is listed in the
502 * fixed scan order tables. This insures we
503 * don't sweep back in channels we filtered out
504 * above.
505 */
506 if (checktable(table, c))
507 continue;
508
509 /* Add channel to scanning list. */
510 ss->ss_chans[ss->ss_last++] = c;
511 }
512}
513
514static void
515makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
516 const struct scanlist table[])
517{
518 const struct scanlist *scan;
519 enum ieee80211_phymode mode;
520
521 ss->ss_last = 0;
522 /*
523 * Use the table of ordered channels to construct the list
524 * of channels for scanning. Any channels in the ordered
525 * list not in the master list will be discarded.
526 */
527 for (scan = table; scan->list != NULL; scan++) {
528 mode = scan->mode;
529 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) {
530 /*
531 * If a desired mode was specified, scan only
532 * channels that satisfy that constraint.
533 */
534 if (vap->iv_des_mode != mode) {
535 /*
536 * The scan table marks 2.4Ghz channels as b
537 * so if the desired mode is 11g, then use
538 * the 11b channel list but upgrade the mode.
539 */
540 if (vap->iv_des_mode != IEEE80211_MODE_11G ||
541 mode != IEEE80211_MODE_11B)
542 continue;
543 mode = IEEE80211_MODE_11G; /* upgrade */
544 }
545 } else {
546 /*
547 * This lets add_channels upgrade an 11b channel
548 * to 11g if available.
549 */
550 if (mode == IEEE80211_MODE_11B)
551 mode = IEEE80211_MODE_AUTO;
552 }
553#ifdef IEEE80211_F_XR
554 /* XR does not operate on turbo channels */
555 if ((vap->iv_flags & IEEE80211_F_XR) &&
556 (mode == IEEE80211_MODE_TURBO_A ||
557 mode == IEEE80211_MODE_TURBO_G ||
558 mode == IEEE80211_MODE_STURBO_A))
559 continue;
560#endif
561 /*
562 * Add the list of the channels; any that are not
563 * in the master channel list will be discarded.
564 */
565 add_channels(vap, ss, mode, scan->list, scan->count);
566 }
567
568 /*
569 * Add the channels from the ic that are not present
570 * in the table.
571 */
572 sweepchannels(ss, vap, table);
573}
574
575static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */
576{ 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 };
577static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */
578{ 5170, 5190, 5210, 5230 };
579static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */
580{ 2412, 2437, 2462, 2442, 2472 };
581static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */
582{ 5745, 5765, 5785, 5805, 5825 };
583static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */
584{ 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 };
585static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */
586{ 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 };
587static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */
588{ 2484 };
589static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */
590{ 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 };
591static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */
592{ 5040, 5060, 5080, 4920, 4940, 4960, 4980 };
593#ifdef ATH_TURBO_SCAN
594static const uint16_t rcl5[] = /* 3 static turbo channels */
595{ 5210, 5250, 5290 };
596static const uint16_t rcl6[] = /* 2 static turbo channels */
597{ 5760, 5800 };
598static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */
599{ 5540, 5580, 5620, 5660 };
600static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */
601{ 2437 };
602static const uint16_t rcl13[] = /* dynamic Turbo channels */
603{ 5200, 5240, 5280, 5765, 5805 };
604#endif /* ATH_TURBO_SCAN */
605
606#define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a
607
608static const struct scanlist staScanTable[] = {
609 { IEEE80211_MODE_11B, X(rcl3) },
610 { IEEE80211_MODE_11A, X(rcl1) },
611 { IEEE80211_MODE_11A, X(rcl2) },
612 { IEEE80211_MODE_11B, X(rcl8) },
613 { IEEE80211_MODE_11B, X(rcl9) },
614 { IEEE80211_MODE_11A, X(rcl4) },
615#ifdef ATH_TURBO_SCAN
616 { IEEE80211_MODE_STURBO_A, X(rcl5) },
617 { IEEE80211_MODE_STURBO_A, X(rcl6) },
618 { IEEE80211_MODE_TURBO_A, X(rcl6x) },
619 { IEEE80211_MODE_TURBO_A, X(rcl13) },
620#endif /* ATH_TURBO_SCAN */
621 { IEEE80211_MODE_11A, X(rcl7) },
622 { IEEE80211_MODE_11B, X(rcl10) },
623 { IEEE80211_MODE_11A, X(rcl11) },
624#ifdef ATH_TURBO_SCAN
625 { IEEE80211_MODE_TURBO_G, X(rcl12) },
626#endif /* ATH_TURBO_SCAN */
627 { .list = NULL }
628};
629
630/*
631 * Start a station-mode scan by populating the channel list.
632 */
633static int
634sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
635{
636 struct sta_table *st = ss->ss_priv;
637
638 makescanlist(ss, vap, staScanTable);
639
640 if (ss->ss_mindwell == 0)
641 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */
642 if (ss->ss_maxdwell == 0)
643 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
644
645 st->st_scangen++;
646 st->st_newscan = 1;
647
648 return 0;
649}
650
651/*
652 * Restart a scan, typically a bg scan but can
653 * also be a fg scan that came up empty.
654 */
655static int
656sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
657{
658 struct sta_table *st = ss->ss_priv;
659
660 st->st_newscan = 1;
661 return 0;
662}
663
664/*
665 * Cancel an ongoing scan.
666 */
667static int
668sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
669{
670 return 0;
671}
672
673/* unalligned little endian access */
674#define LE_READ_2(p) \
675 ((uint16_t) \
676 ((((const uint8_t *)(p))[0] ) | \
677 (((const uint8_t *)(p))[1] << 8)))
678
679static int
680maxrate(const struct ieee80211_scan_entry *se)
681{
682 const struct ieee80211_ie_htcap *htcap =
683 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie;
684 int rmax, r, i;
685 uint16_t caps;
686
687 rmax = 0;
688 if (htcap != NULL) {
689 /*
690 * HT station; inspect supported MCS and then adjust
691 * rate by channel width. Could also include short GI
692 * in this if we want to be extra accurate.
693 */
694 /* XXX assumes MCS15 is max */
695 for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--)
696 ;
697 if (i >= 0) {
698 caps = LE_READ_2(&htcap->hc_cap);
699 /* XXX short/long GI */
700 if (caps & IEEE80211_HTCAP_CHWIDTH40)
701 rmax = ieee80211_htrates[i].ht40_rate_400ns;
702 else
703 rmax = ieee80211_htrates[i].ht40_rate_800ns;
704 }
705 }
706 for (i = 0; i < se->se_rates[1]; i++) {
707 r = se->se_rates[2+i] & IEEE80211_RATE_VAL;
708 if (r > rmax)
709 rmax = r;
710 }
711 for (i = 0; i < se->se_xrates[1]; i++) {
712 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL;
713 if (r > rmax)
714 rmax = r;
715 }
716 return rmax;
717}
718
719/*
720 * Compare the capabilities of two entries and decide which is
721 * more desirable (return >0 if a is considered better). Note
722 * that we assume compatibility/usability has already been checked
723 * so we don't need to (e.g. validate whether privacy is supported).
724 * Used to select the best scan candidate for association in a BSS.
725 */
726static int
727sta_compare(const struct sta_entry *a, const struct sta_entry *b)
728{
729#define PREFER(_a,_b,_what) do { \
730 if (((_a) ^ (_b)) & (_what)) \
731 return ((_a) & (_what)) ? 1 : -1; \
732} while (0)
733 int maxa, maxb;
734 int8_t rssia, rssib;
735 int weight;
736
737 /* privacy support */
738 PREFER(a->base.se_capinfo, b->base.se_capinfo,
739 IEEE80211_CAPINFO_PRIVACY);
740
741 /* compare count of previous failures */
742 weight = b->se_fails - a->se_fails;
743 if (abs(weight) > 1)
744 return weight;
745
746 /*
747 * Compare rssi. If the two are considered equivalent
748 * then fallback to other criteria. We threshold the
749 * comparisons to avoid selecting an ap purely by rssi
750 * when both values may be good but one ap is otherwise
751 * more desirable (e.g. an 11b-only ap with stronger
752 * signal than an 11g ap).
753 */
754 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX);
755 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX);
756 if (abs(rssib - rssia) < 5) {
757 /* best/max rate preferred if signal level close enough XXX */
758 maxa = maxrate(&a->base);
759 maxb = maxrate(&b->base);
760 if (maxa != maxb)
761 return maxa - maxb;
762 /* XXX use freq for channel preference */
763 /* for now just prefer 5Ghz band to all other bands */
764 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan),
765 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1);
766 }
767 /* all things being equal, use signal level */
768 return a->base.se_rssi - b->base.se_rssi;
769#undef PREFER
770}
771
772/*
773 * Check rate set suitability and return the best supported rate.
774 * XXX inspect MCS for HT
775 */
776static int
777check_rate(struct ieee80211vap *vap, const struct ieee80211_scan_entry *se)
778{
779#define RV(v) ((v) & IEEE80211_RATE_VAL)
780 const struct ieee80211_rateset *srs;
781 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate;
782 const uint8_t *rs;
783
784 okrate = badrate = 0;
785
786 srs = ieee80211_get_suprates(vap->iv_ic, se->se_chan);
787 nrs = se->se_rates[1];
788 rs = se->se_rates+2;
789 /* XXX MCS */
790 ucastrate = vap->iv_txparms[ieee80211_chan2mode(se->se_chan)].ucastrate;
791 fixedrate = IEEE80211_FIXED_RATE_NONE;
792again:
793 for (i = 0; i < nrs; i++) {
794 r = RV(rs[i]);
795 badrate = r;
796 /*
797 * Check any fixed rate is included.
798 */
799 if (r == ucastrate)
800 fixedrate = r;
801 /*
802 * Check against our supported rates.
803 */
804 for (j = 0; j < srs->rs_nrates; j++)
805 if (r == RV(srs->rs_rates[j])) {
806 if (r > okrate) /* NB: track max */
807 okrate = r;
808 break;
809 }
810
811 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) {
812 /*
813 * Don't try joining a BSS, if we don't support
814 * one of its basic rates.
815 */
816 okrate = 0;
817 goto back;
818 }
819 }
820 if (rs == se->se_rates+2) {
821 /* scan xrates too; sort of an algol68-style for loop */
822 nrs = se->se_xrates[1];
823 rs = se->se_xrates+2;
824 goto again;
825 }
826
827back:
828 if (okrate == 0 || ucastrate != fixedrate)
829 return badrate | IEEE80211_RATE_BASIC;
830 else
831 return RV(okrate);
832#undef RV
833}
834
835static int
836match_ssid(const uint8_t *ie,
837 int nssid, const struct ieee80211_scan_ssid ssids[])
838{
839 int i;
840
841 for (i = 0; i < nssid; i++) {
842 if (ie[1] == ssids[i].len &&
843 memcmp(ie+2, ssids[i].ssid, ie[1]) == 0)
844 return 1;
845 }
846 return 0;
847}
848
849/*
850 * Test a scan candidate for suitability/compatibility.
851 */
852static int
853match_bss(struct ieee80211vap *vap,
854 const struct ieee80211_scan_state *ss, struct sta_entry *se0,
855 int debug)
856{
857 struct ieee80211com *ic = vap->iv_ic;
858 struct ieee80211_scan_entry *se = &se0->base;
859 uint8_t rate;
860 int fail;
861
862 fail = 0;
863 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan)))
864 fail |= MATCH_CHANNEL;
865 /*
866 * NB: normally the desired mode is used to construct
867 * the channel list, but it's possible for the scan
868 * cache to include entries for stations outside this
869 * list so we check the desired mode here to weed them
870 * out.
871 */
872 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
873 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) !=
874 chanflags[vap->iv_des_mode])
875 fail |= MATCH_CHANNEL;
876 if (vap->iv_opmode == IEEE80211_M_IBSS) {
877 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
878 fail |= MATCH_CAPINFO;
879 } else {
880 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0)
881 fail |= MATCH_CAPINFO;
882 /*
883 * If 11d is enabled and we're attempting to join a bss
884 * that advertises it's country code then compare our
885 * current settings to what we fetched from the country ie.
886 * If our country code is unspecified or different then do
887 * not attempt to join the bss. We should have already
888 * dispatched an event to user space that identifies the
889 * new country code so our regdomain config should match.
890 */
891 if ((IEEE80211_IS_CHAN_11D(se->se_chan) ||
892 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
893 se->se_cc[0] != 0 &&
894 (ic->ic_regdomain.country == CTRY_DEFAULT ||
895 !isocmp(se->se_cc, ic->ic_regdomain.isocc)))
896 fail |= MATCH_CC;
897 }
898 if (vap->iv_flags & IEEE80211_F_PRIVACY) {
899 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
900 fail |= MATCH_PRIVACY;
901 } else {
902 /* XXX does this mean privacy is supported or required? */
903 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY)
904 fail |= MATCH_PRIVACY;
905 }
906 rate = check_rate(vap, se);
907 if (rate & IEEE80211_RATE_BASIC)
908 fail |= MATCH_RATE;
909 if (ss->ss_nssid != 0 &&
910 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid))
911 fail |= MATCH_SSID;
912 if ((vap->iv_flags & IEEE80211_F_DESBSSID) &&
913 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid))
914 fail |= MATCH_BSSID;
915 if (se0->se_fails >= STA_FAILS_MAX)
916 fail |= MATCH_FAILS;
917 if (se0->se_notseen >= STA_PURGE_SCANS)
918 fail |= MATCH_NOTSEEN;
919 if (se->se_rssi < STA_RSSI_MIN)
920 fail |= MATCH_RSSI;
921#ifdef IEEE80211_DEBUG
922 if (ieee80211_msg(vap, debug)) {
923 printf(" %c %s",
924 fail & MATCH_FAILS ? '=' :
925 fail & MATCH_NOTSEEN ? '^' :
926 fail & MATCH_CC ? '$' :
927 fail ? '-' : '+', ether_sprintf(se->se_macaddr));
928 printf(" %s%c", ether_sprintf(se->se_bssid),
929 fail & MATCH_BSSID ? '!' : ' ');
930 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan),
931 fail & MATCH_CHANNEL ? '!' : ' ');
932 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' ');
933 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
934 fail & MATCH_RATE ? '!' : ' ');
935 printf(" %4s%c",
936 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
937 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
938 "????",
939 fail & MATCH_CAPINFO ? '!' : ' ');
940 printf(" %3s%c ",
941 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
942 "wep" : "no",
943 fail & MATCH_PRIVACY ? '!' : ' ');
944 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]);
945 printf("%s\n", fail & MATCH_SSID ? "!" : "");
946 }
947#endif
948 return fail;
949}
950
951static void
952sta_update_notseen(struct sta_table *st)
953{
954 struct sta_entry *se;
955
956 mtx_lock(&st->st_lock);
957 TAILQ_FOREACH(se, &st->st_entry, se_list) {
958 /*
959 * If seen the reset and don't bump the count;
960 * otherwise bump the ``not seen'' count. Note
961 * that this insures that stations for which we
962 * see frames while not scanning but not during
963 * this scan will not be penalized.
964 */
965 if (se->se_seen)
966 se->se_seen = 0;
967 else
968 se->se_notseen++;
969 }
970 mtx_unlock(&st->st_lock);
971}
972
973static void
974sta_dec_fails(struct sta_table *st)
975{
976 struct sta_entry *se;
977
978 mtx_lock(&st->st_lock);
979 TAILQ_FOREACH(se, &st->st_entry, se_list)
980 if (se->se_fails)
981 se->se_fails--;
982 mtx_unlock(&st->st_lock);
983}
984
985static struct sta_entry *
986select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug)
987{
988 struct sta_table *st = ss->ss_priv;
989 struct sta_entry *se, *selbs = NULL;
990
991 IEEE80211_DPRINTF(vap, debug, " %s\n",
992 "macaddr bssid chan rssi rate flag wep essid");
993 mtx_lock(&st->st_lock);
994 TAILQ_FOREACH(se, &st->st_entry, se_list) {
995 if (match_bss(vap, ss, se, debug) == 0) {
996 ieee80211_ies_expand(&se->base.se_ies);
997 if (selbs == NULL)
998 selbs = se;
999 else if (sta_compare(se, selbs) > 0)
1000 selbs = se;
1001 }
1002 }
1003 mtx_unlock(&st->st_lock);
1004
1005 return selbs;
1006}
1007
1008/*
1009 * Pick an ap or ibss network to join or find a channel
1010 * to use to start an ibss network.
1011 */
1012static int
1013sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1014{
1015 struct sta_table *st = ss->ss_priv;
1016 struct sta_entry *selbs;
1017
1018 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1019 ("wrong mode %u", vap->iv_opmode));
1020
1021 if (st->st_newscan) {
1022 sta_update_notseen(st);
1023 st->st_newscan = 0;
1024 }
1025 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1026 /*
1027 * Manual/background scan, don't select+join the
1028 * bss, just return. The scanning framework will
1029 * handle notification that this has completed.
1030 */
1031 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1032 return 1;
1033 }
1034 /*
1035 * Automatic sequencing; look for a candidate and
1036 * if found join the network.
1037 */
1038 /* NB: unlocked read should be ok */
1039 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1040 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1041 "%s: no scan candidate\n", __func__);
1042 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1043 return 0;
1044notfound:
1045 /*
1046 * If nothing suitable was found decrement
1047 * the failure counts so entries will be
1048 * reconsidered the next time around. We
1049 * really want to do this only for sta's
1050 * where we've previously had some success.
1051 */
1052 sta_dec_fails(st);
1053 st->st_newscan = 1;
1054 return 0; /* restart scan */
1055 }
1056 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1057 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1058 return (selbs != NULL);
1059 if (selbs == NULL || !ieee80211_sta_join(vap, &selbs->base))
1060 goto notfound;
1061 return 1; /* terminate scan */
1062}
1063
1064/*
1065 * Lookup an entry in the scan cache. We assume we're
1066 * called from the bottom half or such that we don't need
1067 * to block the bottom half so that it's safe to return
1068 * a reference to an entry w/o holding the lock on the table.
1069 */
1070static struct sta_entry *
1071sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN])
1072{
1073 struct sta_entry *se;
1074 int hash = STA_HASH(macaddr);
1075
1076 mtx_lock(&st->st_lock);
1077 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
1078 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
1079 break;
1080 mtx_unlock(&st->st_lock);
1081
1082 return se; /* NB: unlocked */
1083}
1084
1085static void
1086sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1087{
1088 struct ieee80211com *ic = vap->iv_ic;
1089 struct ieee80211_node *ni = vap->iv_bss;
1090 struct sta_table *st = ss->ss_priv;
1091 enum ieee80211_phymode mode;
1092 struct sta_entry *se, *selbs;
1093 uint8_t roamRate, curRate, ucastRate;
1094 int8_t roamRssi, curRssi;
1095
1096 se = sta_lookup(st, ni->ni_macaddr);
1097 if (se == NULL) {
1098 /* XXX something is wrong */
1099 return;
1100 }
1101
1102 mode = ieee80211_chan2mode(ic->ic_bsschan);
1103 roamRate = vap->iv_roamparms[mode].rate;
1104 roamRssi = vap->iv_roamparms[mode].rssi;
1105 ucastRate = vap->iv_txparms[mode].ucastrate;
1106 /* NB: the most up to date rssi is in the node, not the scan cache */
1107 curRssi = ic->ic_node_getrssi(ni);
1108 if (ucastRate == IEEE80211_FIXED_RATE_NONE) {
1109 curRate = ni->ni_txrate;
1110 roamRate &= IEEE80211_RATE_VAL;
1111 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1112 "%s: currssi %d currate %u roamrssi %d roamrate %u\n",
1113 __func__, curRssi, curRate, roamRssi, roamRate);
1114 } else {
1115 curRate = roamRate; /* NB: insure compare below fails */
1116 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1117 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi);
1118 }
1119 /*
1120 * Check if a new ap should be used and switch.
1121 * XXX deauth current ap
1122 */
1123 if (curRate < roamRate || curRssi < roamRssi) {
1124 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
1125 /*
1126 * Scan cache contents are too old; force a scan now
1127 * if possible so we have current state to make a
1128 * decision with. We don't kick off a bg scan if
1129 * we're using dynamic turbo and boosted or if the
1130 * channel is busy.
1131 * XXX force immediate switch on scan complete
1132 */
1133 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) &&
1134 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle))
1135 ieee80211_bg_scan(vap, 0);
1136 return;
1137 }
1138 se->base.se_rssi = curRssi;
1139 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM);
1140 if (selbs != NULL && selbs != se) {
1141 IEEE80211_DPRINTF(vap,
1142 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG,
1143 "%s: ROAM: curRate %u, roamRate %u, "
1144 "curRssi %d, roamRssi %d\n", __func__,
1145 curRate, roamRate, curRssi, roamRssi);
1146 ieee80211_sta_join(vap, &selbs->base);
1147 }
1148 }
1149}
1150
1151/*
1152 * Age entries in the scan cache.
1153 * XXX also do roaming since it's convenient
1154 */
1155static void
1156sta_age(struct ieee80211_scan_state *ss)
1157{
1158 struct ieee80211vap *vap = ss->ss_vap;
1159
1160 adhoc_age(ss);
1161 /*
1162 * If rate control is enabled check periodically to see if
1163 * we should roam from our current connection to one that
1164 * might be better. This only applies when we're operating
1165 * in sta mode and automatic roaming is set.
1166 * XXX defer if busy
1167 * XXX repeater station
1168 * XXX do when !bgscan?
1169 */
1170 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1171 ("wrong mode %u", vap->iv_opmode));
1172 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO &&
1173 (vap->iv_ic->ic_flags & IEEE80211_F_BGSCAN) &&
1174 vap->iv_state >= IEEE80211_S_RUN)
1175 /* XXX vap is implicit */
1176 sta_roam_check(ss, vap);
1177}
1178
1179/*
1180 * Iterate over the entries in the scan cache, invoking
1181 * the callback function on each one.
1182 */
1183static void
1184sta_iterate(struct ieee80211_scan_state *ss,
1185 ieee80211_scan_iter_func *f, void *arg)
1186{
1187 struct sta_table *st = ss->ss_priv;
1188 struct sta_entry *se;
1189 u_int gen;
1190
1191 mtx_lock(&st->st_scanlock);
1192 gen = st->st_scaniter++;
1193restart:
1194 mtx_lock(&st->st_lock);
1195 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1196 if (se->se_scangen != gen) {
1197 se->se_scangen = gen;
1198 /* update public state */
1199 se->base.se_age = ticks - se->se_lastupdate;
1200 mtx_unlock(&st->st_lock);
1201 (*f)(arg, &se->base);
1202 goto restart;
1203 }
1204 }
1205 mtx_unlock(&st->st_lock);
1206
1207 mtx_unlock(&st->st_scanlock);
1208}
1209
1210static void
1211sta_assoc_fail(struct ieee80211_scan_state *ss,
1212 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason)
1213{
1214 struct sta_table *st = ss->ss_priv;
1215 struct sta_entry *se;
1216
1217 se = sta_lookup(st, macaddr);
1218 if (se != NULL) {
1219 se->se_fails++;
1220 se->se_lastfail = ticks;
1221 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1222 macaddr, "%s: reason %u fails %u",
1223 __func__, reason, se->se_fails);
1224 }
1225}
1226
1227static void
1228sta_assoc_success(struct ieee80211_scan_state *ss,
1229 const uint8_t macaddr[IEEE80211_ADDR_LEN])
1230{
1231 struct sta_table *st = ss->ss_priv;
1232 struct sta_entry *se;
1233
1234 se = sta_lookup(st, macaddr);
1235 if (se != NULL) {
1236#if 0
1237 se->se_fails = 0;
1238 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1239 macaddr, "%s: fails %u",
1240 __func__, se->se_fails);
1241#endif
1242 se->se_lastassoc = ticks;
1243 }
1244}
1245
1246static const struct ieee80211_scanner sta_default = {
1247 .scan_name = "default",
1248 .scan_attach = sta_attach,
1249 .scan_detach = sta_detach,
1250 .scan_start = sta_start,
1251 .scan_restart = sta_restart,
1252 .scan_cancel = sta_cancel,
1253 .scan_end = sta_pick_bss,
1254 .scan_flush = sta_flush,
1255 .scan_add = sta_add,
1256 .scan_age = sta_age,
1257 .scan_iterate = sta_iterate,
1258 .scan_assoc_fail = sta_assoc_fail,
1259 .scan_assoc_success = sta_assoc_success,
1260};
1261
1262/*
1263 * Adhoc mode-specific support.
1264 */
1265
1266static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */
1267{ 5180, 5200, 5220, 5240 };
1268static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */
1269{ 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 };
1270static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */
1271{ 5170, 5190, 5210, 5230 };
1272static const uint16_t adhoc11b[] = /* 10, 11 */
1273{ 2457, 2462 };
1274
1275static const struct scanlist adhocScanTable[] = {
1276 { IEEE80211_MODE_11B, X(adhoc11b) },
1277 { IEEE80211_MODE_11A, X(adhocWorld) },
1278 { IEEE80211_MODE_11A, X(adhocFcc3) },
1279 { IEEE80211_MODE_11B, X(adhocMkk) },
1280 { .list = NULL }
1281};
1282#undef X
1283
1284/*
1285 * Start an adhoc-mode scan by populating the channel list.
1286 */
1287static int
1288adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1289{
1290 struct sta_table *st = ss->ss_priv;
1291
1292 makescanlist(ss, vap, adhocScanTable);
1293
1294 if (ss->ss_mindwell == 0)
1295 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1296 if (ss->ss_maxdwell == 0)
1297 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1298
1299 st->st_scangen++;
1300 st->st_newscan = 1;
1301
1302 return 0;
1303}
1304
1305/*
1306 * Select a channel to start an adhoc network on.
1307 * The channel list was populated with appropriate
1308 * channels so select one that looks least occupied.
1309 */
1310static struct ieee80211_channel *
1311adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags)
1312{
1313 struct sta_table *st = ss->ss_priv;
1314 struct sta_entry *se;
1315 struct ieee80211_channel *c, *bestchan;
1316 int i, bestrssi, maxrssi;
1317
1318 bestchan = NULL;
1319 bestrssi = -1;
1320
1321 mtx_lock(&st->st_lock);
1322 for (i = 0; i < ss->ss_last; i++) {
1323 c = ss->ss_chans[i];
1324 /* never consider a channel with radar */
1325 if (IEEE80211_IS_CHAN_RADAR(c))
1326 continue;
1327 /* skip channels disallowed by regulatory settings */
1328 if (IEEE80211_IS_CHAN_NOADHOC(c))
1329 continue;
1330 /* check channel attributes for band compatibility */
1331 if (flags != 0 && (c->ic_flags & flags) != flags)
1332 continue;
1333 maxrssi = 0;
1334 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1335 if (se->base.se_chan != c)
1336 continue;
1337 if (se->base.se_rssi > maxrssi)
1338 maxrssi = se->base.se_rssi;
1339 }
1340 if (bestchan == NULL || maxrssi < bestrssi)
1341 bestchan = c;
1342 }
1343 mtx_unlock(&st->st_lock);
1344
1345 return bestchan;
1346}
1347
1348/*
1349 * Pick an ibss network to join or find a channel
1350 * to use to start an ibss network.
1351 */
1352static int
1353adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1354{
1355 struct sta_table *st = ss->ss_priv;
1356 struct sta_entry *selbs;
1357 struct ieee80211_channel *chan;
1358
1359 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS ||
1360 vap->iv_opmode == IEEE80211_M_AHDEMO,
1361 ("wrong opmode %u", vap->iv_opmode));
1362
1363 if (st->st_newscan) {
1364 sta_update_notseen(st);
1365 st->st_newscan = 0;
1366 }
1367 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1368 /*
1369 * Manual/background scan, don't select+join the
1370 * bss, just return. The scanning framework will
1371 * handle notification that this has completed.
1372 */
1373 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1374 return 1;
1375 }
1376 /*
1377 * Automatic sequencing; look for a candidate and
1378 * if found join the network.
1379 */
1380 /* NB: unlocked read should be ok */
1381 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1382 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1383 "%s: no scan candidate\n", __func__);
1384 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1385 return 0;
1386notfound:
1387 if (vap->iv_des_nssid) {
1388 /*
1389 * No existing adhoc network to join and we have
1390 * an ssid; start one up. If no channel was
1391 * specified, try to select a channel.
1392 */
1393 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC ||
1394 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
1395 struct ieee80211com *ic = vap->iv_ic;
1396
1397 chan = adhoc_pick_channel(ss, 0);
1398 if (chan != NULL)
1399 chan = ieee80211_ht_adjust_channel(ic,
1400 chan, vap->iv_flags_ext);
1401 } else
1402 chan = vap->iv_des_chan;
1403 if (chan != NULL) {
1404 ieee80211_create_ibss(vap, chan);
1405 return 1;
1406 }
1407 }
1408 /*
1409 * If nothing suitable was found decrement
1410 * the failure counts so entries will be
1411 * reconsidered the next time around. We
1412 * really want to do this only for sta's
1413 * where we've previously had some success.
1414 */
1415 sta_dec_fails(st);
1416 st->st_newscan = 1;
1417 return 0; /* restart scan */
1418 }
1419 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1420 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1421 return (selbs != NULL);
1422 if (selbs == NULL || !ieee80211_sta_join(vap, &selbs->base))
1423 goto notfound;
1424 return 1; /* terminate scan */
1425}
1426
1427/*
1428 * Age entries in the scan cache.
1429 */
1430static void
1431adhoc_age(struct ieee80211_scan_state *ss)
1432{
1433 struct sta_table *st = ss->ss_priv;
1434 struct sta_entry *se, *next;
1435
1436 mtx_lock(&st->st_lock);
1437 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) {
1438 if (se->se_notseen > STA_PURGE_SCANS) {
1439 TAILQ_REMOVE(&st->st_entry, se, se_list);
1440 LIST_REMOVE(se, se_hash);
1441 ieee80211_ies_cleanup(&se->base.se_ies);
233 M_80211_SCAN, M_NOWAIT | M_ZERO);
234 if (se == NULL) {
235 mtx_unlock(&st->st_lock);
236 return 0;
237 }
238 se->se_scangen = st->st_scaniter-1;
239 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER;
240 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr);
241 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list);
242 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash);
243found:
244 ise = &se->base;
245 /* XXX ap beaconing multiple ssid w/ same bssid */
246 if (sp->ssid[1] != 0 &&
247 (ISPROBE(subtype) || ise->se_ssid[1] == 0))
248 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]);
249 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE,
250 ("rate set too large: %u", sp->rates[1]));
251 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]);
252 if (sp->xrates != NULL) {
253 /* XXX validate xrates[1] */
254 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE,
255 ("xrate set too large: %u", sp->xrates[1]));
256 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]);
257 } else
258 ise->se_xrates[1] = 0;
259 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3);
260 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) {
261 /*
262 * Record rssi data using extended precision LPF filter.
263 *
264 * NB: use only on-channel data to insure we get a good
265 * estimate of the signal we'll see when associated.
266 */
267 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi);
268 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi);
269 ise->se_noise = noise;
270 }
271 ise->se_rstamp = rstamp;
272 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp));
273 ise->se_intval = sp->bintval;
274 ise->se_capinfo = sp->capinfo;
275 /*
276 * Beware of overriding se_chan for frames seen
277 * off-channel; this can cause us to attempt an
278 * association on the wrong channel.
279 */
280 if (sp->status & IEEE80211_BPARSE_OFFCHAN) {
281 struct ieee80211_channel *c;
282 /*
283 * Off-channel, locate the home/bss channel for the sta
284 * using the value broadcast in the DSPARMS ie. We know
285 * sp->chan has this value because it's used to calculate
286 * IEEE80211_BPARSE_OFFCHAN.
287 */
288 c = ieee80211_find_channel_byieee(ic, sp->chan,
289 ic->ic_curchan->ic_flags);
290 if (c != NULL) {
291 ise->se_chan = c;
292 } else if (ise->se_chan == NULL) {
293 /* should not happen, pick something */
294 ise->se_chan = ic->ic_curchan;
295 }
296 } else
297 ise->se_chan = ic->ic_curchan;
298 ise->se_fhdwell = sp->fhdwell;
299 ise->se_fhindex = sp->fhindex;
300 ise->se_erp = sp->erp;
301 ise->se_timoff = sp->timoff;
302 if (sp->tim != NULL) {
303 const struct ieee80211_tim_ie *tim =
304 (const struct ieee80211_tim_ie *) sp->tim;
305 ise->se_dtimperiod = tim->tim_period;
306 }
307 if (sp->country != NULL) {
308 const struct ieee80211_country_ie *cie =
309 (const struct ieee80211_country_ie *) sp->country;
310 /*
311 * If 11d is enabled and we're attempting to join a bss
312 * that advertises it's country code then compare our
313 * current settings to what we fetched from the country ie.
314 * If our country code is unspecified or different then
315 * dispatch an event to user space that identifies the
316 * country code so our regdomain config can be changed.
317 */
318 /* XXX only for STA mode? */
319 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) ||
320 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
321 (ic->ic_regdomain.country == CTRY_DEFAULT ||
322 !isocmp(cie->cc, ic->ic_regdomain.isocc))) {
323 /* only issue one notify event per scan */
324 if (se->se_countrygen != st->st_scangen) {
325 ieee80211_notify_country(vap, ise->se_bssid,
326 cie->cc);
327 se->se_countrygen = st->st_scangen;
328 }
329 }
330 ise->se_cc[0] = cie->cc[0];
331 ise->se_cc[1] = cie->cc[1];
332 }
333 /* NB: no need to setup ie ptrs; they are not (currently) used */
334 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len);
335
336 /* clear failure count after STA_FAIL_AGE passes */
337 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) {
338 se->se_fails = 0;
339 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr,
340 "%s: fails %u", __func__, se->se_fails);
341 }
342
343 se->se_lastupdate = ticks; /* update time */
344 se->se_seen = 1;
345 se->se_notseen = 0;
346
347 if (rssi > st->st_maxrssi[sp->bchan])
348 st->st_maxrssi[sp->bchan] = rssi;
349
350 mtx_unlock(&st->st_lock);
351
352 /*
353 * If looking for a quick choice and nothing's
354 * been found check here.
355 */
356 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0)
357 ss->ss_flags |= IEEE80211_SCAN_GOTPICK;
358
359 return 1;
360#undef PICK1ST
361#undef ISPROBE
362}
363
364/*
365 * Check if a channel is excluded by user request.
366 */
367static int
368isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c)
369{
370 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) ||
371 (vap->iv_des_chan != IEEE80211_CHAN_ANYC &&
372 c->ic_freq != vap->iv_des_chan->ic_freq));
373}
374
375static struct ieee80211_channel *
376find11gchannel(struct ieee80211com *ic, int i, int freq)
377{
378 struct ieee80211_channel *c;
379 int j;
380
381 /*
382 * The normal ordering in the channel list is b channel
383 * immediately followed by g so optimize the search for
384 * this. We'll still do a full search just in case.
385 */
386 for (j = i+1; j < ic->ic_nchans; j++) {
387 c = &ic->ic_channels[j];
388 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c))
389 return c;
390 }
391 for (j = 0; j < i; j++) {
392 c = &ic->ic_channels[j];
393 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c))
394 return c;
395 }
396 return NULL;
397}
398static const u_int chanflags[IEEE80211_MODE_MAX] = {
399 IEEE80211_CHAN_B, /* IEEE80211_MODE_AUTO */
400 IEEE80211_CHAN_A, /* IEEE80211_MODE_11A */
401 IEEE80211_CHAN_B, /* IEEE80211_MODE_11B */
402 IEEE80211_CHAN_G, /* IEEE80211_MODE_11G */
403 IEEE80211_CHAN_FHSS, /* IEEE80211_MODE_FH */
404 IEEE80211_CHAN_A, /* IEEE80211_MODE_TURBO_A (check base channel)*/
405 IEEE80211_CHAN_G, /* IEEE80211_MODE_TURBO_G */
406 IEEE80211_CHAN_ST, /* IEEE80211_MODE_STURBO_A */
407 IEEE80211_CHAN_A, /* IEEE80211_MODE_11NA (check legacy) */
408 IEEE80211_CHAN_G, /* IEEE80211_MODE_11NG (check legacy) */
409};
410
411static void
412add_channels(struct ieee80211vap *vap,
413 struct ieee80211_scan_state *ss,
414 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq)
415{
416#define N(a) (sizeof(a) / sizeof(a[0]))
417 struct ieee80211com *ic = vap->iv_ic;
418 struct ieee80211_channel *c, *cg;
419 u_int modeflags;
420 int i;
421
422 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode));
423 modeflags = chanflags[mode];
424 for (i = 0; i < nfreq; i++) {
425 if (ss->ss_last >= IEEE80211_SCAN_MAX)
426 break;
427
428 c = ieee80211_find_channel(ic, freq[i], modeflags);
429 if (c == NULL || isexcluded(vap, c))
430 continue;
431 if (mode == IEEE80211_MODE_AUTO) {
432 /*
433 * XXX special-case 11b/g channels so we select
434 * the g channel if both are present.
435 */
436 if (IEEE80211_IS_CHAN_B(c) &&
437 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL)
438 c = cg;
439 }
440 ss->ss_chans[ss->ss_last++] = c;
441 }
442#undef N
443}
444
445struct scanlist {
446 uint16_t mode;
447 uint16_t count;
448 const uint16_t *list;
449};
450
451static int
452checktable(const struct scanlist *scan, const struct ieee80211_channel *c)
453{
454 int i;
455
456 for (; scan->list != NULL; scan++) {
457 for (i = 0; i < scan->count; i++)
458 if (scan->list[i] == c->ic_freq)
459 return 1;
460 }
461 return 0;
462}
463
464static void
465sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
466 const struct scanlist table[])
467{
468 struct ieee80211com *ic = vap->iv_ic;
469 struct ieee80211_channel *c;
470 int i;
471
472 for (i = 0; i < ic->ic_nchans; i++) {
473 if (ss->ss_last >= IEEE80211_SCAN_MAX)
474 break;
475
476 c = &ic->ic_channels[i];
477 /*
478 * Ignore dynamic turbo channels; we scan them
479 * in normal mode (i.e. not boosted). Likewise
480 * for HT channels, they get scanned using
481 * legacy rates.
482 */
483 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c))
484 continue;
485
486 /*
487 * If a desired mode was specified, scan only
488 * channels that satisfy that constraint.
489 */
490 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
491 vap->iv_des_mode != ieee80211_chan2mode(c))
492 continue;
493
494 /*
495 * Skip channels excluded by user request.
496 */
497 if (isexcluded(vap, c))
498 continue;
499
500 /*
501 * Add the channel unless it is listed in the
502 * fixed scan order tables. This insures we
503 * don't sweep back in channels we filtered out
504 * above.
505 */
506 if (checktable(table, c))
507 continue;
508
509 /* Add channel to scanning list. */
510 ss->ss_chans[ss->ss_last++] = c;
511 }
512}
513
514static void
515makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap,
516 const struct scanlist table[])
517{
518 const struct scanlist *scan;
519 enum ieee80211_phymode mode;
520
521 ss->ss_last = 0;
522 /*
523 * Use the table of ordered channels to construct the list
524 * of channels for scanning. Any channels in the ordered
525 * list not in the master list will be discarded.
526 */
527 for (scan = table; scan->list != NULL; scan++) {
528 mode = scan->mode;
529 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) {
530 /*
531 * If a desired mode was specified, scan only
532 * channels that satisfy that constraint.
533 */
534 if (vap->iv_des_mode != mode) {
535 /*
536 * The scan table marks 2.4Ghz channels as b
537 * so if the desired mode is 11g, then use
538 * the 11b channel list but upgrade the mode.
539 */
540 if (vap->iv_des_mode != IEEE80211_MODE_11G ||
541 mode != IEEE80211_MODE_11B)
542 continue;
543 mode = IEEE80211_MODE_11G; /* upgrade */
544 }
545 } else {
546 /*
547 * This lets add_channels upgrade an 11b channel
548 * to 11g if available.
549 */
550 if (mode == IEEE80211_MODE_11B)
551 mode = IEEE80211_MODE_AUTO;
552 }
553#ifdef IEEE80211_F_XR
554 /* XR does not operate on turbo channels */
555 if ((vap->iv_flags & IEEE80211_F_XR) &&
556 (mode == IEEE80211_MODE_TURBO_A ||
557 mode == IEEE80211_MODE_TURBO_G ||
558 mode == IEEE80211_MODE_STURBO_A))
559 continue;
560#endif
561 /*
562 * Add the list of the channels; any that are not
563 * in the master channel list will be discarded.
564 */
565 add_channels(vap, ss, mode, scan->list, scan->count);
566 }
567
568 /*
569 * Add the channels from the ic that are not present
570 * in the table.
571 */
572 sweepchannels(ss, vap, table);
573}
574
575static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */
576{ 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 };
577static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */
578{ 5170, 5190, 5210, 5230 };
579static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */
580{ 2412, 2437, 2462, 2442, 2472 };
581static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */
582{ 5745, 5765, 5785, 5805, 5825 };
583static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */
584{ 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 };
585static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */
586{ 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 };
587static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */
588{ 2484 };
589static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */
590{ 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 };
591static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */
592{ 5040, 5060, 5080, 4920, 4940, 4960, 4980 };
593#ifdef ATH_TURBO_SCAN
594static const uint16_t rcl5[] = /* 3 static turbo channels */
595{ 5210, 5250, 5290 };
596static const uint16_t rcl6[] = /* 2 static turbo channels */
597{ 5760, 5800 };
598static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */
599{ 5540, 5580, 5620, 5660 };
600static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */
601{ 2437 };
602static const uint16_t rcl13[] = /* dynamic Turbo channels */
603{ 5200, 5240, 5280, 5765, 5805 };
604#endif /* ATH_TURBO_SCAN */
605
606#define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a
607
608static const struct scanlist staScanTable[] = {
609 { IEEE80211_MODE_11B, X(rcl3) },
610 { IEEE80211_MODE_11A, X(rcl1) },
611 { IEEE80211_MODE_11A, X(rcl2) },
612 { IEEE80211_MODE_11B, X(rcl8) },
613 { IEEE80211_MODE_11B, X(rcl9) },
614 { IEEE80211_MODE_11A, X(rcl4) },
615#ifdef ATH_TURBO_SCAN
616 { IEEE80211_MODE_STURBO_A, X(rcl5) },
617 { IEEE80211_MODE_STURBO_A, X(rcl6) },
618 { IEEE80211_MODE_TURBO_A, X(rcl6x) },
619 { IEEE80211_MODE_TURBO_A, X(rcl13) },
620#endif /* ATH_TURBO_SCAN */
621 { IEEE80211_MODE_11A, X(rcl7) },
622 { IEEE80211_MODE_11B, X(rcl10) },
623 { IEEE80211_MODE_11A, X(rcl11) },
624#ifdef ATH_TURBO_SCAN
625 { IEEE80211_MODE_TURBO_G, X(rcl12) },
626#endif /* ATH_TURBO_SCAN */
627 { .list = NULL }
628};
629
630/*
631 * Start a station-mode scan by populating the channel list.
632 */
633static int
634sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
635{
636 struct sta_table *st = ss->ss_priv;
637
638 makescanlist(ss, vap, staScanTable);
639
640 if (ss->ss_mindwell == 0)
641 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */
642 if (ss->ss_maxdwell == 0)
643 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
644
645 st->st_scangen++;
646 st->st_newscan = 1;
647
648 return 0;
649}
650
651/*
652 * Restart a scan, typically a bg scan but can
653 * also be a fg scan that came up empty.
654 */
655static int
656sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
657{
658 struct sta_table *st = ss->ss_priv;
659
660 st->st_newscan = 1;
661 return 0;
662}
663
664/*
665 * Cancel an ongoing scan.
666 */
667static int
668sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
669{
670 return 0;
671}
672
673/* unalligned little endian access */
674#define LE_READ_2(p) \
675 ((uint16_t) \
676 ((((const uint8_t *)(p))[0] ) | \
677 (((const uint8_t *)(p))[1] << 8)))
678
679static int
680maxrate(const struct ieee80211_scan_entry *se)
681{
682 const struct ieee80211_ie_htcap *htcap =
683 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie;
684 int rmax, r, i;
685 uint16_t caps;
686
687 rmax = 0;
688 if (htcap != NULL) {
689 /*
690 * HT station; inspect supported MCS and then adjust
691 * rate by channel width. Could also include short GI
692 * in this if we want to be extra accurate.
693 */
694 /* XXX assumes MCS15 is max */
695 for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--)
696 ;
697 if (i >= 0) {
698 caps = LE_READ_2(&htcap->hc_cap);
699 /* XXX short/long GI */
700 if (caps & IEEE80211_HTCAP_CHWIDTH40)
701 rmax = ieee80211_htrates[i].ht40_rate_400ns;
702 else
703 rmax = ieee80211_htrates[i].ht40_rate_800ns;
704 }
705 }
706 for (i = 0; i < se->se_rates[1]; i++) {
707 r = se->se_rates[2+i] & IEEE80211_RATE_VAL;
708 if (r > rmax)
709 rmax = r;
710 }
711 for (i = 0; i < se->se_xrates[1]; i++) {
712 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL;
713 if (r > rmax)
714 rmax = r;
715 }
716 return rmax;
717}
718
719/*
720 * Compare the capabilities of two entries and decide which is
721 * more desirable (return >0 if a is considered better). Note
722 * that we assume compatibility/usability has already been checked
723 * so we don't need to (e.g. validate whether privacy is supported).
724 * Used to select the best scan candidate for association in a BSS.
725 */
726static int
727sta_compare(const struct sta_entry *a, const struct sta_entry *b)
728{
729#define PREFER(_a,_b,_what) do { \
730 if (((_a) ^ (_b)) & (_what)) \
731 return ((_a) & (_what)) ? 1 : -1; \
732} while (0)
733 int maxa, maxb;
734 int8_t rssia, rssib;
735 int weight;
736
737 /* privacy support */
738 PREFER(a->base.se_capinfo, b->base.se_capinfo,
739 IEEE80211_CAPINFO_PRIVACY);
740
741 /* compare count of previous failures */
742 weight = b->se_fails - a->se_fails;
743 if (abs(weight) > 1)
744 return weight;
745
746 /*
747 * Compare rssi. If the two are considered equivalent
748 * then fallback to other criteria. We threshold the
749 * comparisons to avoid selecting an ap purely by rssi
750 * when both values may be good but one ap is otherwise
751 * more desirable (e.g. an 11b-only ap with stronger
752 * signal than an 11g ap).
753 */
754 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX);
755 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX);
756 if (abs(rssib - rssia) < 5) {
757 /* best/max rate preferred if signal level close enough XXX */
758 maxa = maxrate(&a->base);
759 maxb = maxrate(&b->base);
760 if (maxa != maxb)
761 return maxa - maxb;
762 /* XXX use freq for channel preference */
763 /* for now just prefer 5Ghz band to all other bands */
764 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan),
765 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1);
766 }
767 /* all things being equal, use signal level */
768 return a->base.se_rssi - b->base.se_rssi;
769#undef PREFER
770}
771
772/*
773 * Check rate set suitability and return the best supported rate.
774 * XXX inspect MCS for HT
775 */
776static int
777check_rate(struct ieee80211vap *vap, const struct ieee80211_scan_entry *se)
778{
779#define RV(v) ((v) & IEEE80211_RATE_VAL)
780 const struct ieee80211_rateset *srs;
781 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate;
782 const uint8_t *rs;
783
784 okrate = badrate = 0;
785
786 srs = ieee80211_get_suprates(vap->iv_ic, se->se_chan);
787 nrs = se->se_rates[1];
788 rs = se->se_rates+2;
789 /* XXX MCS */
790 ucastrate = vap->iv_txparms[ieee80211_chan2mode(se->se_chan)].ucastrate;
791 fixedrate = IEEE80211_FIXED_RATE_NONE;
792again:
793 for (i = 0; i < nrs; i++) {
794 r = RV(rs[i]);
795 badrate = r;
796 /*
797 * Check any fixed rate is included.
798 */
799 if (r == ucastrate)
800 fixedrate = r;
801 /*
802 * Check against our supported rates.
803 */
804 for (j = 0; j < srs->rs_nrates; j++)
805 if (r == RV(srs->rs_rates[j])) {
806 if (r > okrate) /* NB: track max */
807 okrate = r;
808 break;
809 }
810
811 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) {
812 /*
813 * Don't try joining a BSS, if we don't support
814 * one of its basic rates.
815 */
816 okrate = 0;
817 goto back;
818 }
819 }
820 if (rs == se->se_rates+2) {
821 /* scan xrates too; sort of an algol68-style for loop */
822 nrs = se->se_xrates[1];
823 rs = se->se_xrates+2;
824 goto again;
825 }
826
827back:
828 if (okrate == 0 || ucastrate != fixedrate)
829 return badrate | IEEE80211_RATE_BASIC;
830 else
831 return RV(okrate);
832#undef RV
833}
834
835static int
836match_ssid(const uint8_t *ie,
837 int nssid, const struct ieee80211_scan_ssid ssids[])
838{
839 int i;
840
841 for (i = 0; i < nssid; i++) {
842 if (ie[1] == ssids[i].len &&
843 memcmp(ie+2, ssids[i].ssid, ie[1]) == 0)
844 return 1;
845 }
846 return 0;
847}
848
849/*
850 * Test a scan candidate for suitability/compatibility.
851 */
852static int
853match_bss(struct ieee80211vap *vap,
854 const struct ieee80211_scan_state *ss, struct sta_entry *se0,
855 int debug)
856{
857 struct ieee80211com *ic = vap->iv_ic;
858 struct ieee80211_scan_entry *se = &se0->base;
859 uint8_t rate;
860 int fail;
861
862 fail = 0;
863 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan)))
864 fail |= MATCH_CHANNEL;
865 /*
866 * NB: normally the desired mode is used to construct
867 * the channel list, but it's possible for the scan
868 * cache to include entries for stations outside this
869 * list so we check the desired mode here to weed them
870 * out.
871 */
872 if (vap->iv_des_mode != IEEE80211_MODE_AUTO &&
873 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) !=
874 chanflags[vap->iv_des_mode])
875 fail |= MATCH_CHANNEL;
876 if (vap->iv_opmode == IEEE80211_M_IBSS) {
877 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0)
878 fail |= MATCH_CAPINFO;
879 } else {
880 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0)
881 fail |= MATCH_CAPINFO;
882 /*
883 * If 11d is enabled and we're attempting to join a bss
884 * that advertises it's country code then compare our
885 * current settings to what we fetched from the country ie.
886 * If our country code is unspecified or different then do
887 * not attempt to join the bss. We should have already
888 * dispatched an event to user space that identifies the
889 * new country code so our regdomain config should match.
890 */
891 if ((IEEE80211_IS_CHAN_11D(se->se_chan) ||
892 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) &&
893 se->se_cc[0] != 0 &&
894 (ic->ic_regdomain.country == CTRY_DEFAULT ||
895 !isocmp(se->se_cc, ic->ic_regdomain.isocc)))
896 fail |= MATCH_CC;
897 }
898 if (vap->iv_flags & IEEE80211_F_PRIVACY) {
899 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0)
900 fail |= MATCH_PRIVACY;
901 } else {
902 /* XXX does this mean privacy is supported or required? */
903 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY)
904 fail |= MATCH_PRIVACY;
905 }
906 rate = check_rate(vap, se);
907 if (rate & IEEE80211_RATE_BASIC)
908 fail |= MATCH_RATE;
909 if (ss->ss_nssid != 0 &&
910 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid))
911 fail |= MATCH_SSID;
912 if ((vap->iv_flags & IEEE80211_F_DESBSSID) &&
913 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid))
914 fail |= MATCH_BSSID;
915 if (se0->se_fails >= STA_FAILS_MAX)
916 fail |= MATCH_FAILS;
917 if (se0->se_notseen >= STA_PURGE_SCANS)
918 fail |= MATCH_NOTSEEN;
919 if (se->se_rssi < STA_RSSI_MIN)
920 fail |= MATCH_RSSI;
921#ifdef IEEE80211_DEBUG
922 if (ieee80211_msg(vap, debug)) {
923 printf(" %c %s",
924 fail & MATCH_FAILS ? '=' :
925 fail & MATCH_NOTSEEN ? '^' :
926 fail & MATCH_CC ? '$' :
927 fail ? '-' : '+', ether_sprintf(se->se_macaddr));
928 printf(" %s%c", ether_sprintf(se->se_bssid),
929 fail & MATCH_BSSID ? '!' : ' ');
930 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan),
931 fail & MATCH_CHANNEL ? '!' : ' ');
932 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' ');
933 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2,
934 fail & MATCH_RATE ? '!' : ' ');
935 printf(" %4s%c",
936 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" :
937 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" :
938 "????",
939 fail & MATCH_CAPINFO ? '!' : ' ');
940 printf(" %3s%c ",
941 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ?
942 "wep" : "no",
943 fail & MATCH_PRIVACY ? '!' : ' ');
944 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]);
945 printf("%s\n", fail & MATCH_SSID ? "!" : "");
946 }
947#endif
948 return fail;
949}
950
951static void
952sta_update_notseen(struct sta_table *st)
953{
954 struct sta_entry *se;
955
956 mtx_lock(&st->st_lock);
957 TAILQ_FOREACH(se, &st->st_entry, se_list) {
958 /*
959 * If seen the reset and don't bump the count;
960 * otherwise bump the ``not seen'' count. Note
961 * that this insures that stations for which we
962 * see frames while not scanning but not during
963 * this scan will not be penalized.
964 */
965 if (se->se_seen)
966 se->se_seen = 0;
967 else
968 se->se_notseen++;
969 }
970 mtx_unlock(&st->st_lock);
971}
972
973static void
974sta_dec_fails(struct sta_table *st)
975{
976 struct sta_entry *se;
977
978 mtx_lock(&st->st_lock);
979 TAILQ_FOREACH(se, &st->st_entry, se_list)
980 if (se->se_fails)
981 se->se_fails--;
982 mtx_unlock(&st->st_lock);
983}
984
985static struct sta_entry *
986select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug)
987{
988 struct sta_table *st = ss->ss_priv;
989 struct sta_entry *se, *selbs = NULL;
990
991 IEEE80211_DPRINTF(vap, debug, " %s\n",
992 "macaddr bssid chan rssi rate flag wep essid");
993 mtx_lock(&st->st_lock);
994 TAILQ_FOREACH(se, &st->st_entry, se_list) {
995 if (match_bss(vap, ss, se, debug) == 0) {
996 ieee80211_ies_expand(&se->base.se_ies);
997 if (selbs == NULL)
998 selbs = se;
999 else if (sta_compare(se, selbs) > 0)
1000 selbs = se;
1001 }
1002 }
1003 mtx_unlock(&st->st_lock);
1004
1005 return selbs;
1006}
1007
1008/*
1009 * Pick an ap or ibss network to join or find a channel
1010 * to use to start an ibss network.
1011 */
1012static int
1013sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1014{
1015 struct sta_table *st = ss->ss_priv;
1016 struct sta_entry *selbs;
1017
1018 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1019 ("wrong mode %u", vap->iv_opmode));
1020
1021 if (st->st_newscan) {
1022 sta_update_notseen(st);
1023 st->st_newscan = 0;
1024 }
1025 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1026 /*
1027 * Manual/background scan, don't select+join the
1028 * bss, just return. The scanning framework will
1029 * handle notification that this has completed.
1030 */
1031 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1032 return 1;
1033 }
1034 /*
1035 * Automatic sequencing; look for a candidate and
1036 * if found join the network.
1037 */
1038 /* NB: unlocked read should be ok */
1039 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1040 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1041 "%s: no scan candidate\n", __func__);
1042 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1043 return 0;
1044notfound:
1045 /*
1046 * If nothing suitable was found decrement
1047 * the failure counts so entries will be
1048 * reconsidered the next time around. We
1049 * really want to do this only for sta's
1050 * where we've previously had some success.
1051 */
1052 sta_dec_fails(st);
1053 st->st_newscan = 1;
1054 return 0; /* restart scan */
1055 }
1056 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1057 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1058 return (selbs != NULL);
1059 if (selbs == NULL || !ieee80211_sta_join(vap, &selbs->base))
1060 goto notfound;
1061 return 1; /* terminate scan */
1062}
1063
1064/*
1065 * Lookup an entry in the scan cache. We assume we're
1066 * called from the bottom half or such that we don't need
1067 * to block the bottom half so that it's safe to return
1068 * a reference to an entry w/o holding the lock on the table.
1069 */
1070static struct sta_entry *
1071sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN])
1072{
1073 struct sta_entry *se;
1074 int hash = STA_HASH(macaddr);
1075
1076 mtx_lock(&st->st_lock);
1077 LIST_FOREACH(se, &st->st_hash[hash], se_hash)
1078 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr))
1079 break;
1080 mtx_unlock(&st->st_lock);
1081
1082 return se; /* NB: unlocked */
1083}
1084
1085static void
1086sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1087{
1088 struct ieee80211com *ic = vap->iv_ic;
1089 struct ieee80211_node *ni = vap->iv_bss;
1090 struct sta_table *st = ss->ss_priv;
1091 enum ieee80211_phymode mode;
1092 struct sta_entry *se, *selbs;
1093 uint8_t roamRate, curRate, ucastRate;
1094 int8_t roamRssi, curRssi;
1095
1096 se = sta_lookup(st, ni->ni_macaddr);
1097 if (se == NULL) {
1098 /* XXX something is wrong */
1099 return;
1100 }
1101
1102 mode = ieee80211_chan2mode(ic->ic_bsschan);
1103 roamRate = vap->iv_roamparms[mode].rate;
1104 roamRssi = vap->iv_roamparms[mode].rssi;
1105 ucastRate = vap->iv_txparms[mode].ucastrate;
1106 /* NB: the most up to date rssi is in the node, not the scan cache */
1107 curRssi = ic->ic_node_getrssi(ni);
1108 if (ucastRate == IEEE80211_FIXED_RATE_NONE) {
1109 curRate = ni->ni_txrate;
1110 roamRate &= IEEE80211_RATE_VAL;
1111 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1112 "%s: currssi %d currate %u roamrssi %d roamrate %u\n",
1113 __func__, curRssi, curRate, roamRssi, roamRate);
1114 } else {
1115 curRate = roamRate; /* NB: insure compare below fails */
1116 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM,
1117 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi);
1118 }
1119 /*
1120 * Check if a new ap should be used and switch.
1121 * XXX deauth current ap
1122 */
1123 if (curRate < roamRate || curRssi < roamRssi) {
1124 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) {
1125 /*
1126 * Scan cache contents are too old; force a scan now
1127 * if possible so we have current state to make a
1128 * decision with. We don't kick off a bg scan if
1129 * we're using dynamic turbo and boosted or if the
1130 * channel is busy.
1131 * XXX force immediate switch on scan complete
1132 */
1133 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) &&
1134 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle))
1135 ieee80211_bg_scan(vap, 0);
1136 return;
1137 }
1138 se->base.se_rssi = curRssi;
1139 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM);
1140 if (selbs != NULL && selbs != se) {
1141 IEEE80211_DPRINTF(vap,
1142 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG,
1143 "%s: ROAM: curRate %u, roamRate %u, "
1144 "curRssi %d, roamRssi %d\n", __func__,
1145 curRate, roamRate, curRssi, roamRssi);
1146 ieee80211_sta_join(vap, &selbs->base);
1147 }
1148 }
1149}
1150
1151/*
1152 * Age entries in the scan cache.
1153 * XXX also do roaming since it's convenient
1154 */
1155static void
1156sta_age(struct ieee80211_scan_state *ss)
1157{
1158 struct ieee80211vap *vap = ss->ss_vap;
1159
1160 adhoc_age(ss);
1161 /*
1162 * If rate control is enabled check periodically to see if
1163 * we should roam from our current connection to one that
1164 * might be better. This only applies when we're operating
1165 * in sta mode and automatic roaming is set.
1166 * XXX defer if busy
1167 * XXX repeater station
1168 * XXX do when !bgscan?
1169 */
1170 KASSERT(vap->iv_opmode == IEEE80211_M_STA,
1171 ("wrong mode %u", vap->iv_opmode));
1172 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO &&
1173 (vap->iv_ic->ic_flags & IEEE80211_F_BGSCAN) &&
1174 vap->iv_state >= IEEE80211_S_RUN)
1175 /* XXX vap is implicit */
1176 sta_roam_check(ss, vap);
1177}
1178
1179/*
1180 * Iterate over the entries in the scan cache, invoking
1181 * the callback function on each one.
1182 */
1183static void
1184sta_iterate(struct ieee80211_scan_state *ss,
1185 ieee80211_scan_iter_func *f, void *arg)
1186{
1187 struct sta_table *st = ss->ss_priv;
1188 struct sta_entry *se;
1189 u_int gen;
1190
1191 mtx_lock(&st->st_scanlock);
1192 gen = st->st_scaniter++;
1193restart:
1194 mtx_lock(&st->st_lock);
1195 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1196 if (se->se_scangen != gen) {
1197 se->se_scangen = gen;
1198 /* update public state */
1199 se->base.se_age = ticks - se->se_lastupdate;
1200 mtx_unlock(&st->st_lock);
1201 (*f)(arg, &se->base);
1202 goto restart;
1203 }
1204 }
1205 mtx_unlock(&st->st_lock);
1206
1207 mtx_unlock(&st->st_scanlock);
1208}
1209
1210static void
1211sta_assoc_fail(struct ieee80211_scan_state *ss,
1212 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason)
1213{
1214 struct sta_table *st = ss->ss_priv;
1215 struct sta_entry *se;
1216
1217 se = sta_lookup(st, macaddr);
1218 if (se != NULL) {
1219 se->se_fails++;
1220 se->se_lastfail = ticks;
1221 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1222 macaddr, "%s: reason %u fails %u",
1223 __func__, reason, se->se_fails);
1224 }
1225}
1226
1227static void
1228sta_assoc_success(struct ieee80211_scan_state *ss,
1229 const uint8_t macaddr[IEEE80211_ADDR_LEN])
1230{
1231 struct sta_table *st = ss->ss_priv;
1232 struct sta_entry *se;
1233
1234 se = sta_lookup(st, macaddr);
1235 if (se != NULL) {
1236#if 0
1237 se->se_fails = 0;
1238 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN,
1239 macaddr, "%s: fails %u",
1240 __func__, se->se_fails);
1241#endif
1242 se->se_lastassoc = ticks;
1243 }
1244}
1245
1246static const struct ieee80211_scanner sta_default = {
1247 .scan_name = "default",
1248 .scan_attach = sta_attach,
1249 .scan_detach = sta_detach,
1250 .scan_start = sta_start,
1251 .scan_restart = sta_restart,
1252 .scan_cancel = sta_cancel,
1253 .scan_end = sta_pick_bss,
1254 .scan_flush = sta_flush,
1255 .scan_add = sta_add,
1256 .scan_age = sta_age,
1257 .scan_iterate = sta_iterate,
1258 .scan_assoc_fail = sta_assoc_fail,
1259 .scan_assoc_success = sta_assoc_success,
1260};
1261
1262/*
1263 * Adhoc mode-specific support.
1264 */
1265
1266static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */
1267{ 5180, 5200, 5220, 5240 };
1268static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */
1269{ 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 };
1270static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */
1271{ 5170, 5190, 5210, 5230 };
1272static const uint16_t adhoc11b[] = /* 10, 11 */
1273{ 2457, 2462 };
1274
1275static const struct scanlist adhocScanTable[] = {
1276 { IEEE80211_MODE_11B, X(adhoc11b) },
1277 { IEEE80211_MODE_11A, X(adhocWorld) },
1278 { IEEE80211_MODE_11A, X(adhocFcc3) },
1279 { IEEE80211_MODE_11B, X(adhocMkk) },
1280 { .list = NULL }
1281};
1282#undef X
1283
1284/*
1285 * Start an adhoc-mode scan by populating the channel list.
1286 */
1287static int
1288adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1289{
1290 struct sta_table *st = ss->ss_priv;
1291
1292 makescanlist(ss, vap, adhocScanTable);
1293
1294 if (ss->ss_mindwell == 0)
1295 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1296 if (ss->ss_maxdwell == 0)
1297 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1298
1299 st->st_scangen++;
1300 st->st_newscan = 1;
1301
1302 return 0;
1303}
1304
1305/*
1306 * Select a channel to start an adhoc network on.
1307 * The channel list was populated with appropriate
1308 * channels so select one that looks least occupied.
1309 */
1310static struct ieee80211_channel *
1311adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags)
1312{
1313 struct sta_table *st = ss->ss_priv;
1314 struct sta_entry *se;
1315 struct ieee80211_channel *c, *bestchan;
1316 int i, bestrssi, maxrssi;
1317
1318 bestchan = NULL;
1319 bestrssi = -1;
1320
1321 mtx_lock(&st->st_lock);
1322 for (i = 0; i < ss->ss_last; i++) {
1323 c = ss->ss_chans[i];
1324 /* never consider a channel with radar */
1325 if (IEEE80211_IS_CHAN_RADAR(c))
1326 continue;
1327 /* skip channels disallowed by regulatory settings */
1328 if (IEEE80211_IS_CHAN_NOADHOC(c))
1329 continue;
1330 /* check channel attributes for band compatibility */
1331 if (flags != 0 && (c->ic_flags & flags) != flags)
1332 continue;
1333 maxrssi = 0;
1334 TAILQ_FOREACH(se, &st->st_entry, se_list) {
1335 if (se->base.se_chan != c)
1336 continue;
1337 if (se->base.se_rssi > maxrssi)
1338 maxrssi = se->base.se_rssi;
1339 }
1340 if (bestchan == NULL || maxrssi < bestrssi)
1341 bestchan = c;
1342 }
1343 mtx_unlock(&st->st_lock);
1344
1345 return bestchan;
1346}
1347
1348/*
1349 * Pick an ibss network to join or find a channel
1350 * to use to start an ibss network.
1351 */
1352static int
1353adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1354{
1355 struct sta_table *st = ss->ss_priv;
1356 struct sta_entry *selbs;
1357 struct ieee80211_channel *chan;
1358
1359 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS ||
1360 vap->iv_opmode == IEEE80211_M_AHDEMO,
1361 ("wrong opmode %u", vap->iv_opmode));
1362
1363 if (st->st_newscan) {
1364 sta_update_notseen(st);
1365 st->st_newscan = 0;
1366 }
1367 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) {
1368 /*
1369 * Manual/background scan, don't select+join the
1370 * bss, just return. The scanning framework will
1371 * handle notification that this has completed.
1372 */
1373 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1374 return 1;
1375 }
1376 /*
1377 * Automatic sequencing; look for a candidate and
1378 * if found join the network.
1379 */
1380 /* NB: unlocked read should be ok */
1381 if (TAILQ_FIRST(&st->st_entry) == NULL) {
1382 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1383 "%s: no scan candidate\n", __func__);
1384 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1385 return 0;
1386notfound:
1387 if (vap->iv_des_nssid) {
1388 /*
1389 * No existing adhoc network to join and we have
1390 * an ssid; start one up. If no channel was
1391 * specified, try to select a channel.
1392 */
1393 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC ||
1394 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) {
1395 struct ieee80211com *ic = vap->iv_ic;
1396
1397 chan = adhoc_pick_channel(ss, 0);
1398 if (chan != NULL)
1399 chan = ieee80211_ht_adjust_channel(ic,
1400 chan, vap->iv_flags_ext);
1401 } else
1402 chan = vap->iv_des_chan;
1403 if (chan != NULL) {
1404 ieee80211_create_ibss(vap, chan);
1405 return 1;
1406 }
1407 }
1408 /*
1409 * If nothing suitable was found decrement
1410 * the failure counts so entries will be
1411 * reconsidered the next time around. We
1412 * really want to do this only for sta's
1413 * where we've previously had some success.
1414 */
1415 sta_dec_fails(st);
1416 st->st_newscan = 1;
1417 return 0; /* restart scan */
1418 }
1419 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN);
1420 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN)
1421 return (selbs != NULL);
1422 if (selbs == NULL || !ieee80211_sta_join(vap, &selbs->base))
1423 goto notfound;
1424 return 1; /* terminate scan */
1425}
1426
1427/*
1428 * Age entries in the scan cache.
1429 */
1430static void
1431adhoc_age(struct ieee80211_scan_state *ss)
1432{
1433 struct sta_table *st = ss->ss_priv;
1434 struct sta_entry *se, *next;
1435
1436 mtx_lock(&st->st_lock);
1437 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) {
1438 if (se->se_notseen > STA_PURGE_SCANS) {
1439 TAILQ_REMOVE(&st->st_entry, se, se_list);
1440 LIST_REMOVE(se, se_hash);
1441 ieee80211_ies_cleanup(&se->base.se_ies);
1442 free(se, M_80211_SCAN);
1442 FREE(se, M_80211_SCAN);
1443 }
1444 }
1445 mtx_unlock(&st->st_lock);
1446}
1447
1448static const struct ieee80211_scanner adhoc_default = {
1449 .scan_name = "default",
1450 .scan_attach = sta_attach,
1451 .scan_detach = sta_detach,
1452 .scan_start = adhoc_start,
1453 .scan_restart = sta_restart,
1454 .scan_cancel = sta_cancel,
1455 .scan_end = adhoc_pick_bss,
1456 .scan_flush = sta_flush,
1457 .scan_pickchan = adhoc_pick_channel,
1458 .scan_add = sta_add,
1459 .scan_age = adhoc_age,
1460 .scan_iterate = sta_iterate,
1461 .scan_assoc_fail = sta_assoc_fail,
1462 .scan_assoc_success = sta_assoc_success,
1463};
1464
1465static void
1466ap_force_promisc(struct ieee80211com *ic)
1467{
1468 struct ifnet *ifp = ic->ic_ifp;
1469
1470 IEEE80211_LOCK(ic);
1471 /* set interface into promiscuous mode */
1472 ifp->if_flags |= IFF_PROMISC;
1473 ic->ic_update_promisc(ifp);
1474 IEEE80211_UNLOCK(ic);
1475}
1476
1477static void
1478ap_reset_promisc(struct ieee80211com *ic)
1479{
1480 IEEE80211_LOCK(ic);
1481 ieee80211_syncifflag_locked(ic, IFF_PROMISC);
1482 IEEE80211_UNLOCK(ic);
1483}
1484
1485static int
1486ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1487{
1488 struct sta_table *st = ss->ss_priv;
1489
1490 makescanlist(ss, vap, staScanTable);
1491
1492 if (ss->ss_mindwell == 0)
1493 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1494 if (ss->ss_maxdwell == 0)
1495 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1496
1497 st->st_scangen++;
1498 st->st_newscan = 1;
1499
1500 ap_force_promisc(vap->iv_ic);
1501 return 0;
1502}
1503
1504/*
1505 * Cancel an ongoing scan.
1506 */
1507static int
1508ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1509{
1510 ap_reset_promisc(vap->iv_ic);
1511 return 0;
1512}
1513
1514/*
1515 * Pick a quiet channel to use for ap operation.
1516 */
1517static struct ieee80211_channel *
1518ap_pick_channel(struct ieee80211_scan_state *ss, int flags)
1519{
1520 struct sta_table *st = ss->ss_priv;
1521 struct ieee80211_channel *bestchan = NULL;
1522 int i;
1523
1524 /* XXX select channel more intelligently, e.g. channel spread, power */
1525 /* NB: use scan list order to preserve channel preference */
1526 for (i = 0; i < ss->ss_last; i++) {
1527 struct ieee80211_channel *chan = ss->ss_chans[i];
1528 /*
1529 * If the channel is unoccupied the max rssi
1530 * should be zero; just take it. Otherwise
1531 * track the channel with the lowest rssi and
1532 * use that when all channels appear occupied.
1533 */
1534 if (IEEE80211_IS_CHAN_RADAR(chan))
1535 continue;
1536 if (IEEE80211_IS_CHAN_NOHOSTAP(chan))
1537 continue;
1538 /* check channel attributes for band compatibility */
1539 if (flags != 0 && (chan->ic_flags & flags) != flags)
1540 continue;
1541 /* XXX channel have interference */
1542 if (st->st_maxrssi[chan->ic_ieee] == 0) {
1543 /* XXX use other considerations */
1544 return chan;
1545 }
1546 if (bestchan == NULL ||
1547 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee])
1548 bestchan = chan;
1549 }
1550 return bestchan;
1551}
1552
1553/*
1554 * Pick a quiet channel to use for ap operation.
1555 */
1556static int
1557ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1558{
1559 struct ieee80211com *ic = vap->iv_ic;
1560 struct ieee80211_channel *bestchan;
1561
1562 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP,
1563 ("wrong opmode %u", vap->iv_opmode));
1564 bestchan = ap_pick_channel(ss, 0);
1565 if (bestchan == NULL) {
1566 /* no suitable channel, should not happen */
1567 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1568 "%s: no suitable channel! (should not happen)\n", __func__);
1569 /* XXX print something? */
1570 return 0; /* restart scan */
1571 }
1572 /*
1573 * If this is a dynamic turbo channel, start with the unboosted one.
1574 */
1575 if (IEEE80211_IS_CHAN_TURBO(bestchan)) {
1576 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq,
1577 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO);
1578 if (bestchan == NULL) {
1579 /* should never happen ?? */
1580 return 0;
1581 }
1582 }
1583 ap_reset_promisc(ic);
1584 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) {
1585 /*
1586 * Manual/background scan, don't select+join the
1587 * bss, just return. The scanning framework will
1588 * handle notification that this has completed.
1589 */
1590 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1591 return 1;
1592 }
1593 ieee80211_create_ibss(vap,
1594 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ext));
1595 return 1;
1596}
1597
1598static const struct ieee80211_scanner ap_default = {
1599 .scan_name = "default",
1600 .scan_attach = sta_attach,
1601 .scan_detach = sta_detach,
1602 .scan_start = ap_start,
1603 .scan_restart = sta_restart,
1604 .scan_cancel = ap_cancel,
1605 .scan_end = ap_end,
1606 .scan_flush = sta_flush,
1607 .scan_pickchan = ap_pick_channel,
1608 .scan_add = sta_add,
1609 .scan_age = adhoc_age,
1610 .scan_iterate = sta_iterate,
1611 .scan_assoc_success = sta_assoc_success,
1612 .scan_assoc_fail = sta_assoc_fail,
1613};
1614
1615/*
1616 * Module glue.
1617 */
1618IEEE80211_SCANNER_MODULE(sta, 1);
1619IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default);
1620IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default);
1621IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default);
1622IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default);
1443 }
1444 }
1445 mtx_unlock(&st->st_lock);
1446}
1447
1448static const struct ieee80211_scanner adhoc_default = {
1449 .scan_name = "default",
1450 .scan_attach = sta_attach,
1451 .scan_detach = sta_detach,
1452 .scan_start = adhoc_start,
1453 .scan_restart = sta_restart,
1454 .scan_cancel = sta_cancel,
1455 .scan_end = adhoc_pick_bss,
1456 .scan_flush = sta_flush,
1457 .scan_pickchan = adhoc_pick_channel,
1458 .scan_add = sta_add,
1459 .scan_age = adhoc_age,
1460 .scan_iterate = sta_iterate,
1461 .scan_assoc_fail = sta_assoc_fail,
1462 .scan_assoc_success = sta_assoc_success,
1463};
1464
1465static void
1466ap_force_promisc(struct ieee80211com *ic)
1467{
1468 struct ifnet *ifp = ic->ic_ifp;
1469
1470 IEEE80211_LOCK(ic);
1471 /* set interface into promiscuous mode */
1472 ifp->if_flags |= IFF_PROMISC;
1473 ic->ic_update_promisc(ifp);
1474 IEEE80211_UNLOCK(ic);
1475}
1476
1477static void
1478ap_reset_promisc(struct ieee80211com *ic)
1479{
1480 IEEE80211_LOCK(ic);
1481 ieee80211_syncifflag_locked(ic, IFF_PROMISC);
1482 IEEE80211_UNLOCK(ic);
1483}
1484
1485static int
1486ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1487{
1488 struct sta_table *st = ss->ss_priv;
1489
1490 makescanlist(ss, vap, staScanTable);
1491
1492 if (ss->ss_mindwell == 0)
1493 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */
1494 if (ss->ss_maxdwell == 0)
1495 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */
1496
1497 st->st_scangen++;
1498 st->st_newscan = 1;
1499
1500 ap_force_promisc(vap->iv_ic);
1501 return 0;
1502}
1503
1504/*
1505 * Cancel an ongoing scan.
1506 */
1507static int
1508ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1509{
1510 ap_reset_promisc(vap->iv_ic);
1511 return 0;
1512}
1513
1514/*
1515 * Pick a quiet channel to use for ap operation.
1516 */
1517static struct ieee80211_channel *
1518ap_pick_channel(struct ieee80211_scan_state *ss, int flags)
1519{
1520 struct sta_table *st = ss->ss_priv;
1521 struct ieee80211_channel *bestchan = NULL;
1522 int i;
1523
1524 /* XXX select channel more intelligently, e.g. channel spread, power */
1525 /* NB: use scan list order to preserve channel preference */
1526 for (i = 0; i < ss->ss_last; i++) {
1527 struct ieee80211_channel *chan = ss->ss_chans[i];
1528 /*
1529 * If the channel is unoccupied the max rssi
1530 * should be zero; just take it. Otherwise
1531 * track the channel with the lowest rssi and
1532 * use that when all channels appear occupied.
1533 */
1534 if (IEEE80211_IS_CHAN_RADAR(chan))
1535 continue;
1536 if (IEEE80211_IS_CHAN_NOHOSTAP(chan))
1537 continue;
1538 /* check channel attributes for band compatibility */
1539 if (flags != 0 && (chan->ic_flags & flags) != flags)
1540 continue;
1541 /* XXX channel have interference */
1542 if (st->st_maxrssi[chan->ic_ieee] == 0) {
1543 /* XXX use other considerations */
1544 return chan;
1545 }
1546 if (bestchan == NULL ||
1547 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee])
1548 bestchan = chan;
1549 }
1550 return bestchan;
1551}
1552
1553/*
1554 * Pick a quiet channel to use for ap operation.
1555 */
1556static int
1557ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap)
1558{
1559 struct ieee80211com *ic = vap->iv_ic;
1560 struct ieee80211_channel *bestchan;
1561
1562 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP,
1563 ("wrong opmode %u", vap->iv_opmode));
1564 bestchan = ap_pick_channel(ss, 0);
1565 if (bestchan == NULL) {
1566 /* no suitable channel, should not happen */
1567 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
1568 "%s: no suitable channel! (should not happen)\n", __func__);
1569 /* XXX print something? */
1570 return 0; /* restart scan */
1571 }
1572 /*
1573 * If this is a dynamic turbo channel, start with the unboosted one.
1574 */
1575 if (IEEE80211_IS_CHAN_TURBO(bestchan)) {
1576 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq,
1577 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO);
1578 if (bestchan == NULL) {
1579 /* should never happen ?? */
1580 return 0;
1581 }
1582 }
1583 ap_reset_promisc(ic);
1584 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) {
1585 /*
1586 * Manual/background scan, don't select+join the
1587 * bss, just return. The scanning framework will
1588 * handle notification that this has completed.
1589 */
1590 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK;
1591 return 1;
1592 }
1593 ieee80211_create_ibss(vap,
1594 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ext));
1595 return 1;
1596}
1597
1598static const struct ieee80211_scanner ap_default = {
1599 .scan_name = "default",
1600 .scan_attach = sta_attach,
1601 .scan_detach = sta_detach,
1602 .scan_start = ap_start,
1603 .scan_restart = sta_restart,
1604 .scan_cancel = ap_cancel,
1605 .scan_end = ap_end,
1606 .scan_flush = sta_flush,
1607 .scan_pickchan = ap_pick_channel,
1608 .scan_add = sta_add,
1609 .scan_age = adhoc_age,
1610 .scan_iterate = sta_iterate,
1611 .scan_assoc_success = sta_assoc_success,
1612 .scan_assoc_fail = sta_assoc_fail,
1613};
1614
1615/*
1616 * Module glue.
1617 */
1618IEEE80211_SCANNER_MODULE(sta, 1);
1619IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default);
1620IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default);
1621IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default);
1622IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default);