ieee80211_scan_sta.c revision 298359
1/*- 2 * Copyright (c) 2002-2009 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 298359 2016-04-20 18:29:30Z avos $"); 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/endian.h> 38#include <sys/malloc.h> 39#include <sys/module.h> 40 41#include <sys/socket.h> 42 43#include <net/if.h> 44#include <net/if_var.h> 45#include <net/if_media.h> 46#include <net/ethernet.h> 47 48#include <net80211/ieee80211_var.h> 49#include <net80211/ieee80211_input.h> 50#include <net80211/ieee80211_regdomain.h> 51#ifdef IEEE80211_SUPPORT_TDMA 52#include <net80211/ieee80211_tdma.h> 53#endif 54#ifdef IEEE80211_SUPPORT_MESH 55#include <net80211/ieee80211_mesh.h> 56#endif 57#include <net80211/ieee80211_ratectl.h> 58 59#include <net/bpf.h> 60 61/* 62 * Parameters for managing cache entries: 63 * 64 * o a station with STA_FAILS_MAX failures is not considered 65 * when picking a candidate 66 * o a station that hasn't had an update in STA_PURGE_SCANS 67 * (background) scans is discarded 68 * o after STA_FAILS_AGE seconds we clear the failure count 69 */ 70#define STA_FAILS_MAX 2 /* assoc failures before ignored */ 71#define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ 72#define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ 73 74/* XXX tunable */ 75#define STA_RSSI_MIN 8 /* min acceptable rssi */ 76#define STA_RSSI_MAX 40 /* max rssi for comparison */ 77 78struct sta_entry { 79 struct ieee80211_scan_entry base; 80 TAILQ_ENTRY(sta_entry) se_list; 81 LIST_ENTRY(sta_entry) se_hash; 82 uint8_t se_fails; /* failure to associate count */ 83 uint8_t se_seen; /* seen during current scan */ 84 uint8_t se_notseen; /* not seen in previous scans */ 85 uint8_t se_flags; 86#define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ 87 uint32_t se_avgrssi; /* LPF rssi state */ 88 unsigned long se_lastupdate; /* time of last update */ 89 unsigned long se_lastfail; /* time of last failure */ 90 unsigned long se_lastassoc; /* time of last association */ 91 u_int se_scangen; /* iterator scan gen# */ 92 u_int se_countrygen; /* gen# of last cc notify */ 93}; 94 95#define STA_HASHSIZE 32 96/* simple hash is enough for variation of macaddr */ 97#define STA_HASH(addr) \ 98 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) 99 100#define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */ 101CTASSERT(MAX_IEEE_CHAN >= 256); 102 103struct sta_table { 104 ieee80211_scan_table_lock_t st_lock; /* on scan table */ 105 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 106 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 107 ieee80211_scan_iter_lock_t st_scanlock; /* on st_scaniter */ 108 u_int st_scaniter; /* gen# for iterator */ 109 u_int st_scangen; /* scan generation # */ 110 int st_newscan; 111 /* ap-related state */ 112 int st_maxrssi[MAX_IEEE_CHAN]; 113}; 114 115static void sta_flush_table(struct sta_table *); 116/* 117 * match_bss returns a bitmask describing if an entry is suitable 118 * for use. If non-zero the entry was deemed not suitable and it's 119 * contents explains why. The following flags are or'd to to this 120 * mask and can be used to figure out why the entry was rejected. 121 */ 122#define MATCH_CHANNEL 0x00001 /* channel mismatch */ 123#define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ 124#define MATCH_PRIVACY 0x00004 /* privacy mismatch */ 125#define MATCH_RATE 0x00008 /* rate set mismatch */ 126#define MATCH_SSID 0x00010 /* ssid mismatch */ 127#define MATCH_BSSID 0x00020 /* bssid mismatch */ 128#define MATCH_FAILS 0x00040 /* too many failed auth attempts */ 129#define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ 130#define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ 131#define MATCH_CC 0x00200 /* country code mismatch */ 132#define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ 133#define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ 134#define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ 135#define MATCH_TDMA_LOCAL 0x02000 /* local address */ 136#define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ 137#define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ 138#define MATCH_MESHID 0x20000 /* meshid mismatch */ 139static int match_bss(struct ieee80211vap *, 140 const struct ieee80211_scan_state *, struct sta_entry *, int); 141static void adhoc_age(struct ieee80211_scan_state *); 142 143static __inline int 144isocmp(const uint8_t cc1[], const uint8_t cc2[]) 145{ 146 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 147} 148 149/* number of references from net80211 layer */ 150static int nrefs = 0; 151/* 152 * Module glue. 153 */ 154IEEE80211_SCANNER_MODULE(sta, 1); 155 156/* 157 * Attach prior to any scanning work. 158 */ 159static int 160sta_attach(struct ieee80211_scan_state *ss) 161{ 162 struct sta_table *st; 163 164 st = (struct sta_table *) IEEE80211_MALLOC(sizeof(struct sta_table), 165 M_80211_SCAN, 166 IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 167 if (st == NULL) 168 return 0; 169 IEEE80211_SCAN_TABLE_LOCK_INIT(st, "scantable"); 170 IEEE80211_SCAN_ITER_LOCK_INIT(st, "scangen"); 171 TAILQ_INIT(&st->st_entry); 172 ss->ss_priv = st; 173 nrefs++; /* NB: we assume caller locking */ 174 return 1; 175} 176 177/* 178 * Cleanup any private state. 179 */ 180static int 181sta_detach(struct ieee80211_scan_state *ss) 182{ 183 struct sta_table *st = ss->ss_priv; 184 185 if (st != NULL) { 186 sta_flush_table(st); 187 IEEE80211_SCAN_TABLE_LOCK_DESTROY(st); 188 IEEE80211_SCAN_ITER_LOCK_DESTROY(st); 189 IEEE80211_FREE(st, M_80211_SCAN); 190 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 191 nrefs--; /* NB: we assume caller locking */ 192 } 193 return 1; 194} 195 196/* 197 * Flush all per-scan state. 198 */ 199static int 200sta_flush(struct ieee80211_scan_state *ss) 201{ 202 struct sta_table *st = ss->ss_priv; 203 204 IEEE80211_SCAN_TABLE_LOCK(st); 205 sta_flush_table(st); 206 IEEE80211_SCAN_TABLE_UNLOCK(st); 207 ss->ss_last = 0; 208 return 0; 209} 210 211/* 212 * Flush all entries in the scan cache. 213 */ 214static void 215sta_flush_table(struct sta_table *st) 216{ 217 struct sta_entry *se, *next; 218 219 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 220 TAILQ_REMOVE(&st->st_entry, se, se_list); 221 LIST_REMOVE(se, se_hash); 222 ieee80211_ies_cleanup(&se->base.se_ies); 223 IEEE80211_FREE(se, M_80211_SCAN); 224 } 225 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 226} 227 228/* 229 * Process a beacon or probe response frame; create an 230 * entry in the scan cache or update any previous entry. 231 */ 232static int 233sta_add(struct ieee80211_scan_state *ss, 234 struct ieee80211_channel *curchan, 235 const struct ieee80211_scanparams *sp, 236 const struct ieee80211_frame *wh, 237 int subtype, int rssi, int noise) 238{ 239#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 240#define PICK1ST(_ss) \ 241 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 242 IEEE80211_SCAN_PICK1ST) 243 struct sta_table *st = ss->ss_priv; 244 const uint8_t *macaddr = wh->i_addr2; 245 struct ieee80211vap *vap = ss->ss_vap; 246 struct ieee80211com *ic = vap->iv_ic; 247 struct ieee80211_channel *c; 248 struct sta_entry *se; 249 struct ieee80211_scan_entry *ise; 250 int hash; 251 252 hash = STA_HASH(macaddr); 253 254 IEEE80211_SCAN_TABLE_LOCK(st); 255 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 256 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 257 goto found; 258 se = (struct sta_entry *) IEEE80211_MALLOC(sizeof(struct sta_entry), 259 M_80211_SCAN, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 260 if (se == NULL) { 261 IEEE80211_SCAN_TABLE_UNLOCK(st); 262 return 0; 263 } 264 se->se_scangen = st->st_scaniter-1; 265 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 266 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 267 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 268 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 269found: 270 ise = &se->base; 271 /* XXX ap beaconing multiple ssid w/ same bssid */ 272 if (sp->ssid[1] != 0 && 273 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 274 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 275 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 276 ("rate set too large: %u", sp->rates[1])); 277 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 278 if (sp->xrates != NULL) { 279 /* XXX validate xrates[1] */ 280 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 281 ("xrate set too large: %u", sp->xrates[1])); 282 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 283 } else 284 ise->se_xrates[1] = 0; 285 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 286 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 287 /* 288 * Record rssi data using extended precision LPF filter. 289 * 290 * NB: use only on-channel data to insure we get a good 291 * estimate of the signal we'll see when associated. 292 */ 293 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 294 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 295 ise->se_noise = noise; 296 } 297 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 298 ise->se_intval = sp->bintval; 299 ise->se_capinfo = sp->capinfo; 300#ifdef IEEE80211_SUPPORT_MESH 301 if (sp->meshid != NULL && sp->meshid[1] != 0) 302 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); 303#endif 304 /* 305 * Beware of overriding se_chan for frames seen 306 * off-channel; this can cause us to attempt an 307 * association on the wrong channel. 308 */ 309 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 310 /* 311 * Off-channel, locate the home/bss channel for the sta 312 * using the value broadcast in the DSPARMS ie. We know 313 * sp->chan has this value because it's used to calculate 314 * IEEE80211_BPARSE_OFFCHAN. 315 */ 316 c = ieee80211_find_channel_byieee(ic, sp->chan, 317 curchan->ic_flags); 318 if (c != NULL) { 319 ise->se_chan = c; 320 } else if (ise->se_chan == NULL) { 321 /* should not happen, pick something */ 322 ise->se_chan = curchan; 323 } 324 } else 325 ise->se_chan = curchan; 326 if (IEEE80211_IS_CHAN_HT(ise->se_chan) && sp->htcap == NULL) { 327 /* Demote legacy networks to a non-HT channel. */ 328 c = ieee80211_find_channel(ic, ise->se_chan->ic_freq, 329 ise->se_chan->ic_flags & ~IEEE80211_CHAN_HT); 330 KASSERT(c != NULL, 331 ("no legacy channel %u", ise->se_chan->ic_ieee)); 332 ise->se_chan = c; 333 } 334 ise->se_fhdwell = sp->fhdwell; 335 ise->se_fhindex = sp->fhindex; 336 ise->se_erp = sp->erp; 337 ise->se_timoff = sp->timoff; 338 if (sp->tim != NULL) { 339 const struct ieee80211_tim_ie *tim = 340 (const struct ieee80211_tim_ie *) sp->tim; 341 ise->se_dtimperiod = tim->tim_period; 342 } 343 if (sp->country != NULL) { 344 const struct ieee80211_country_ie *cie = 345 (const struct ieee80211_country_ie *) sp->country; 346 /* 347 * If 11d is enabled and we're attempting to join a bss 348 * that advertises it's country code then compare our 349 * current settings to what we fetched from the country ie. 350 * If our country code is unspecified or different then 351 * dispatch an event to user space that identifies the 352 * country code so our regdomain config can be changed. 353 */ 354 /* XXX only for STA mode? */ 355 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 356 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 357 (ic->ic_regdomain.country == CTRY_DEFAULT || 358 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 359 /* only issue one notify event per scan */ 360 if (se->se_countrygen != st->st_scangen) { 361 ieee80211_notify_country(vap, ise->se_bssid, 362 cie->cc); 363 se->se_countrygen = st->st_scangen; 364 } 365 } 366 ise->se_cc[0] = cie->cc[0]; 367 ise->se_cc[1] = cie->cc[1]; 368 } 369 /* NB: no need to setup ie ptrs; they are not (currently) used */ 370 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 371 372 /* clear failure count after STA_FAIL_AGE passes */ 373 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 374 se->se_fails = 0; 375 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 376 "%s: fails %u", __func__, se->se_fails); 377 } 378 379 se->se_lastupdate = ticks; /* update time */ 380 se->se_seen = 1; 381 se->se_notseen = 0; 382 383 KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); 384 if (rssi > st->st_maxrssi[sp->bchan]) 385 st->st_maxrssi[sp->bchan] = rssi; 386 387 IEEE80211_SCAN_TABLE_UNLOCK(st); 388 389 /* 390 * If looking for a quick choice and nothing's 391 * been found check here. 392 */ 393 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 394 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 395 396 return 1; 397#undef PICK1ST 398#undef ISPROBE 399} 400 401/* 402 * Check if a channel is excluded by user request. 403 */ 404static int 405isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 406{ 407 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 408 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 409 c->ic_freq != vap->iv_des_chan->ic_freq)); 410} 411 412static struct ieee80211_channel * 413find11gchannel(struct ieee80211com *ic, int i, int freq) 414{ 415 struct ieee80211_channel *c; 416 int j; 417 418 /* 419 * The normal ordering in the channel list is b channel 420 * immediately followed by g so optimize the search for 421 * this. We'll still do a full search just in case. 422 */ 423 for (j = i+1; j < ic->ic_nchans; j++) { 424 c = &ic->ic_channels[j]; 425 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 426 return c; 427 } 428 for (j = 0; j < i; j++) { 429 c = &ic->ic_channels[j]; 430 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 431 return c; 432 } 433 return NULL; 434} 435 436static const u_int chanflags[IEEE80211_MODE_MAX] = { 437 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, 438 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, 439 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, 440 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, 441 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, 442 /* check base channel */ 443 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, 444 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, 445 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, 446 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, 447 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, 448 /* check legacy */ 449 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, 450 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, 451}; 452 453static void 454add_channels(struct ieee80211vap *vap, 455 struct ieee80211_scan_state *ss, 456 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 457{ 458 struct ieee80211com *ic = vap->iv_ic; 459 struct ieee80211_channel *c, *cg; 460 u_int modeflags; 461 int i; 462 463 KASSERT(mode < nitems(chanflags), ("Unexpected mode %u", mode)); 464 modeflags = chanflags[mode]; 465 for (i = 0; i < nfreq; i++) { 466 if (ss->ss_last >= IEEE80211_SCAN_MAX) 467 break; 468 469 c = ieee80211_find_channel(ic, freq[i], modeflags); 470 if (c == NULL || isexcluded(vap, c)) 471 continue; 472 if (mode == IEEE80211_MODE_AUTO) { 473 /* 474 * XXX special-case 11b/g channels so we select 475 * the g channel if both are present. 476 */ 477 if (IEEE80211_IS_CHAN_B(c) && 478 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 479 c = cg; 480 } 481 ss->ss_chans[ss->ss_last++] = c; 482 } 483} 484 485struct scanlist { 486 uint16_t mode; 487 uint16_t count; 488 const uint16_t *list; 489}; 490 491static int 492checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 493{ 494 int i; 495 496 for (; scan->list != NULL; scan++) { 497 for (i = 0; i < scan->count; i++) 498 if (scan->list[i] == c->ic_freq) 499 return 1; 500 } 501 return 0; 502} 503 504static int 505onscanlist(const struct ieee80211_scan_state *ss, 506 const struct ieee80211_channel *c) 507{ 508 int i; 509 510 for (i = 0; i < ss->ss_last; i++) 511 if (ss->ss_chans[i] == c) 512 return 1; 513 return 0; 514} 515 516static void 517sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 518 const struct scanlist table[]) 519{ 520 struct ieee80211com *ic = vap->iv_ic; 521 struct ieee80211_channel *c; 522 int i; 523 524 for (i = 0; i < ic->ic_nchans; i++) { 525 if (ss->ss_last >= IEEE80211_SCAN_MAX) 526 break; 527 528 c = &ic->ic_channels[i]; 529 /* 530 * Ignore dynamic turbo channels; we scan them 531 * in normal mode (i.e. not boosted). Likewise 532 * for HT channels, they get scanned using 533 * legacy rates. 534 */ 535 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) 536 continue; 537 538 /* 539 * If a desired mode was specified, scan only 540 * channels that satisfy that constraint. 541 */ 542 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 543 vap->iv_des_mode != ieee80211_chan2mode(c)) 544 continue; 545 546 /* 547 * Skip channels excluded by user request. 548 */ 549 if (isexcluded(vap, c)) 550 continue; 551 552 /* 553 * Add the channel unless it is listed in the 554 * fixed scan order tables. This insures we 555 * don't sweep back in channels we filtered out 556 * above. 557 */ 558 if (checktable(table, c)) 559 continue; 560 561 /* Add channel to scanning list. */ 562 ss->ss_chans[ss->ss_last++] = c; 563 } 564 /* 565 * Explicitly add any desired channel if: 566 * - not already on the scan list 567 * - allowed by any desired mode constraint 568 * - there is space in the scan list 569 * This allows the channel to be used when the filtering 570 * mechanisms would otherwise elide it (e.g HT, turbo). 571 */ 572 c = vap->iv_des_chan; 573 if (c != IEEE80211_CHAN_ANYC && 574 !onscanlist(ss, c) && 575 (vap->iv_des_mode == IEEE80211_MODE_AUTO || 576 vap->iv_des_mode == ieee80211_chan2mode(c)) && 577 ss->ss_last < IEEE80211_SCAN_MAX) 578 ss->ss_chans[ss->ss_last++] = c; 579} 580 581static void 582makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 583 const struct scanlist table[]) 584{ 585 const struct scanlist *scan; 586 enum ieee80211_phymode mode; 587 588 ss->ss_last = 0; 589 /* 590 * Use the table of ordered channels to construct the list 591 * of channels for scanning. Any channels in the ordered 592 * list not in the master list will be discarded. 593 */ 594 for (scan = table; scan->list != NULL; scan++) { 595 mode = scan->mode; 596 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { 597 /* 598 * If a desired mode was specified, scan only 599 * channels that satisfy that constraint. 600 */ 601 if (vap->iv_des_mode != mode) { 602 /* 603 * The scan table marks 2.4Ghz channels as b 604 * so if the desired mode is 11g, then use 605 * the 11b channel list but upgrade the mode. 606 */ 607 if (vap->iv_des_mode == IEEE80211_MODE_11G) { 608 if (mode == IEEE80211_MODE_11G) /* Skip the G check */ 609 continue; 610 else if (mode == IEEE80211_MODE_11B) 611 mode = IEEE80211_MODE_11G; /* upgrade */ 612 } 613 } 614 } else { 615 /* 616 * This lets add_channels upgrade an 11b channel 617 * to 11g if available. 618 */ 619 if (mode == IEEE80211_MODE_11B) 620 mode = IEEE80211_MODE_AUTO; 621 } 622#ifdef IEEE80211_F_XR 623 /* XR does not operate on turbo channels */ 624 if ((vap->iv_flags & IEEE80211_F_XR) && 625 (mode == IEEE80211_MODE_TURBO_A || 626 mode == IEEE80211_MODE_TURBO_G || 627 mode == IEEE80211_MODE_STURBO_A)) 628 continue; 629#endif 630 /* 631 * Add the list of the channels; any that are not 632 * in the master channel list will be discarded. 633 */ 634 add_channels(vap, ss, mode, scan->list, scan->count); 635 } 636 637 /* 638 * Add the channels from the ic that are not present 639 * in the table. 640 */ 641 sweepchannels(ss, vap, table); 642} 643 644static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 645{ 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 646static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 647{ 5170, 5190, 5210, 5230 }; 648static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 649{ 2412, 2437, 2462, 2442, 2472 }; 650static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 651{ 5745, 5765, 5785, 5805, 5825 }; 652static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 653{ 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 654static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 655{ 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 656static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 657{ 2484 }; 658static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 659{ 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 660static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 661{ 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 662#ifdef ATH_TURBO_SCAN 663static const uint16_t rcl5[] = /* 3 static turbo channels */ 664{ 5210, 5250, 5290 }; 665static const uint16_t rcl6[] = /* 2 static turbo channels */ 666{ 5760, 5800 }; 667static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 668{ 5540, 5580, 5620, 5660 }; 669static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 670{ 2437 }; 671static const uint16_t rcl13[] = /* dynamic Turbo channels */ 672{ 5200, 5240, 5280, 5765, 5805 }; 673#endif /* ATH_TURBO_SCAN */ 674 675#define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 676 677static const struct scanlist staScanTable[] = { 678 { IEEE80211_MODE_11B, X(rcl3) }, 679 { IEEE80211_MODE_11A, X(rcl1) }, 680 { IEEE80211_MODE_11A, X(rcl2) }, 681 { IEEE80211_MODE_11B, X(rcl8) }, 682 { IEEE80211_MODE_11B, X(rcl9) }, 683 { IEEE80211_MODE_11A, X(rcl4) }, 684#ifdef ATH_TURBO_SCAN 685 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 686 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 687 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 688 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 689#endif /* ATH_TURBO_SCAN */ 690 { IEEE80211_MODE_11A, X(rcl7) }, 691 { IEEE80211_MODE_11B, X(rcl10) }, 692 { IEEE80211_MODE_11A, X(rcl11) }, 693#ifdef ATH_TURBO_SCAN 694 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 695#endif /* ATH_TURBO_SCAN */ 696 { .list = NULL } 697}; 698 699/* 700 * Start a station-mode scan by populating the channel list. 701 */ 702static int 703sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 704{ 705 struct sta_table *st = ss->ss_priv; 706 707 makescanlist(ss, vap, staScanTable); 708 709 if (ss->ss_mindwell == 0) 710 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 711 if (ss->ss_maxdwell == 0) 712 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 713 714 st->st_scangen++; 715 st->st_newscan = 1; 716 717 return 0; 718} 719 720/* 721 * Restart a scan, typically a bg scan but can 722 * also be a fg scan that came up empty. 723 */ 724static int 725sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 726{ 727 struct sta_table *st = ss->ss_priv; 728 729 st->st_newscan = 1; 730 return 0; 731} 732 733/* 734 * Cancel an ongoing scan. 735 */ 736static int 737sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 738{ 739 return 0; 740} 741 742/* 743 * Demote any supplied 11g channel to 11b. There should 744 * always be an 11b channel but we check anyway... 745 */ 746static struct ieee80211_channel * 747demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 748{ 749 struct ieee80211_channel *c; 750 751 if (IEEE80211_IS_CHAN_ANYG(chan) && 752 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 753 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 754 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 755 IEEE80211_CHAN_B); 756 if (c != NULL) 757 chan = c; 758 } 759 return chan; 760} 761 762static int 763maxrate(const struct ieee80211_scan_entry *se) 764{ 765 const struct ieee80211_ie_htcap *htcap = 766 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 767 int rmax, r, i, txstream; 768 uint16_t caps; 769 uint8_t txparams; 770 771 rmax = 0; 772 if (htcap != NULL) { 773 /* 774 * HT station; inspect supported MCS and then adjust 775 * rate by channel width. 776 */ 777 txparams = htcap->hc_mcsset[12]; 778 if (txparams & 0x3) { 779 /* 780 * TX MCS parameters defined and not equal to RX, 781 * extract the number of spartial streams and 782 * map it to the highest MCS rate. 783 */ 784 txstream = ((txparams & 0xc) >> 2) + 1; 785 i = txstream * 8 - 1; 786 } else 787 for (i = 31; i >= 0 && isclr(htcap->hc_mcsset, i); i--); 788 if (i >= 0) { 789 caps = le16dec(&htcap->hc_cap); 790 if ((caps & IEEE80211_HTCAP_CHWIDTH40) && 791 (caps & IEEE80211_HTCAP_SHORTGI40)) 792 rmax = ieee80211_htrates[i].ht40_rate_400ns; 793 else if (caps & IEEE80211_HTCAP_CHWIDTH40) 794 rmax = ieee80211_htrates[i].ht40_rate_800ns; 795 else if (caps & IEEE80211_HTCAP_SHORTGI20) 796 rmax = ieee80211_htrates[i].ht20_rate_400ns; 797 else 798 rmax = ieee80211_htrates[i].ht20_rate_800ns; 799 } 800 } 801 for (i = 0; i < se->se_rates[1]; i++) { 802 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 803 if (r > rmax) 804 rmax = r; 805 } 806 for (i = 0; i < se->se_xrates[1]; i++) { 807 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 808 if (r > rmax) 809 rmax = r; 810 } 811 return rmax; 812} 813 814/* 815 * Compare the capabilities of two entries and decide which is 816 * more desirable (return >0 if a is considered better). Note 817 * that we assume compatibility/usability has already been checked 818 * so we don't need to (e.g. validate whether privacy is supported). 819 * Used to select the best scan candidate for association in a BSS. 820 */ 821static int 822sta_compare(const struct sta_entry *a, const struct sta_entry *b) 823{ 824#define PREFER(_a,_b,_what) do { \ 825 if (((_a) ^ (_b)) & (_what)) \ 826 return ((_a) & (_what)) ? 1 : -1; \ 827} while (0) 828 int maxa, maxb; 829 int8_t rssia, rssib; 830 int weight; 831 832 /* privacy support */ 833 PREFER(a->base.se_capinfo, b->base.se_capinfo, 834 IEEE80211_CAPINFO_PRIVACY); 835 836 /* compare count of previous failures */ 837 weight = b->se_fails - a->se_fails; 838 if (abs(weight) > 1) 839 return weight; 840 841 /* 842 * Compare rssi. If the two are considered equivalent 843 * then fallback to other criteria. We threshold the 844 * comparisons to avoid selecting an ap purely by rssi 845 * when both values may be good but one ap is otherwise 846 * more desirable (e.g. an 11b-only ap with stronger 847 * signal than an 11g ap). 848 */ 849 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 850 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 851 if (abs(rssib - rssia) < 5) { 852 /* best/max rate preferred if signal level close enough XXX */ 853 maxa = maxrate(&a->base); 854 maxb = maxrate(&b->base); 855 if (maxa != maxb) 856 return maxa - maxb; 857 /* XXX use freq for channel preference */ 858 /* for now just prefer 5Ghz band to all other bands */ 859 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 860 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 861 } 862 /* all things being equal, use signal level */ 863 return a->base.se_rssi - b->base.se_rssi; 864#undef PREFER 865} 866 867/* 868 * Check rate set suitability and return the best supported rate. 869 * XXX inspect MCS for HT 870 */ 871static int 872check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 873 const struct ieee80211_scan_entry *se) 874{ 875 const struct ieee80211_rateset *srs; 876 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 877 const uint8_t *rs; 878 879 okrate = badrate = 0; 880 881 srs = ieee80211_get_suprates(vap->iv_ic, chan); 882 nrs = se->se_rates[1]; 883 rs = se->se_rates+2; 884 /* XXX MCS */ 885 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 886 fixedrate = IEEE80211_FIXED_RATE_NONE; 887again: 888 for (i = 0; i < nrs; i++) { 889 r = IEEE80211_RV(rs[i]); 890 badrate = r; 891 /* 892 * Check any fixed rate is included. 893 */ 894 if (r == ucastrate) 895 fixedrate = r; 896 /* 897 * Check against our supported rates. 898 */ 899 for (j = 0; j < srs->rs_nrates; j++) 900 if (r == IEEE80211_RV(srs->rs_rates[j])) { 901 if (r > okrate) /* NB: track max */ 902 okrate = r; 903 break; 904 } 905 906 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 907 /* 908 * Don't try joining a BSS, if we don't support 909 * one of its basic rates. 910 */ 911 okrate = 0; 912 goto back; 913 } 914 } 915 if (rs == se->se_rates+2) { 916 /* scan xrates too; sort of an algol68-style for loop */ 917 nrs = se->se_xrates[1]; 918 rs = se->se_xrates+2; 919 goto again; 920 } 921 922back: 923 if (okrate == 0 || ucastrate != fixedrate) 924 return badrate | IEEE80211_RATE_BASIC; 925 else 926 return IEEE80211_RV(okrate); 927} 928 929static __inline int 930match_id(const uint8_t *ie, const uint8_t *val, int len) 931{ 932 return (ie[1] == len && memcmp(ie+2, val, len) == 0); 933} 934 935static int 936match_ssid(const uint8_t *ie, 937 int nssid, const struct ieee80211_scan_ssid ssids[]) 938{ 939 int i; 940 941 for (i = 0; i < nssid; i++) { 942 if (match_id(ie, ssids[i].ssid, ssids[i].len)) 943 return 1; 944 } 945 return 0; 946} 947 948#ifdef IEEE80211_SUPPORT_TDMA 949static int 950tdma_isfull(const struct ieee80211_tdma_param *tdma) 951{ 952 int slot, slotcnt; 953 954 slotcnt = tdma->tdma_slotcnt; 955 for (slot = slotcnt-1; slot >= 0; slot--) 956 if (isclr(tdma->tdma_inuse, slot)) 957 return 0; 958 return 1; 959} 960#endif /* IEEE80211_SUPPORT_TDMA */ 961 962/* 963 * Test a scan candidate for suitability/compatibility. 964 */ 965static int 966match_bss(struct ieee80211vap *vap, 967 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 968 int debug) 969{ 970 struct ieee80211com *ic = vap->iv_ic; 971 struct ieee80211_scan_entry *se = &se0->base; 972 uint8_t rate; 973 int fail; 974 975 fail = 0; 976 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 977 fail |= MATCH_CHANNEL; 978 /* 979 * NB: normally the desired mode is used to construct 980 * the channel list, but it's possible for the scan 981 * cache to include entries for stations outside this 982 * list so we check the desired mode here to weed them 983 * out. 984 */ 985 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 986 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 987 chanflags[vap->iv_des_mode]) 988 fail |= MATCH_CHANNEL; 989 if (vap->iv_opmode == IEEE80211_M_IBSS) { 990 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 991 fail |= MATCH_CAPINFO; 992#ifdef IEEE80211_SUPPORT_TDMA 993 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { 994 /* 995 * Adhoc demo network setup shouldn't really be scanning 996 * but just in case skip stations operating in IBSS or 997 * BSS mode. 998 */ 999 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1000 fail |= MATCH_CAPINFO; 1001 /* 1002 * TDMA operation cannot coexist with a normal 802.11 network; 1003 * skip if IBSS or ESS capabilities are marked and require 1004 * the beacon have a TDMA ie present. 1005 */ 1006 if (vap->iv_caps & IEEE80211_C_TDMA) { 1007 const struct ieee80211_tdma_param *tdma = 1008 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; 1009 const struct ieee80211_tdma_state *ts = vap->iv_tdma; 1010 1011 if (tdma == NULL) 1012 fail |= MATCH_TDMA_NOIE; 1013 else if (tdma->tdma_version != ts->tdma_version) 1014 fail |= MATCH_TDMA_VERSION; 1015 else if (tdma->tdma_slot != 0) 1016 fail |= MATCH_TDMA_NOTMASTER; 1017 else if (tdma_isfull(tdma)) 1018 fail |= MATCH_TDMA_NOSLOT; 1019#if 0 1020 else if (ieee80211_local_address(se->se_macaddr)) 1021 fail |= MATCH_TDMA_LOCAL; 1022#endif 1023 } 1024#endif /* IEEE80211_SUPPORT_TDMA */ 1025#ifdef IEEE80211_SUPPORT_MESH 1026 } else if (vap->iv_opmode == IEEE80211_M_MBSS) { 1027 const struct ieee80211_mesh_state *ms = vap->iv_mesh; 1028 /* 1029 * Mesh nodes have IBSS & ESS bits in capinfo turned off 1030 * and two special ie's that must be present. 1031 */ 1032 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1033 fail |= MATCH_CAPINFO; 1034 else if (se->se_meshid[0] != IEEE80211_ELEMID_MESHID) 1035 fail |= MATCH_MESH_NOID; 1036 else if (ms->ms_idlen != 0 && 1037 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) 1038 fail |= MATCH_MESHID; 1039#endif 1040 } else { 1041 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 1042 fail |= MATCH_CAPINFO; 1043 /* 1044 * If 11d is enabled and we're attempting to join a bss 1045 * that advertises it's country code then compare our 1046 * current settings to what we fetched from the country ie. 1047 * If our country code is unspecified or different then do 1048 * not attempt to join the bss. We should have already 1049 * dispatched an event to user space that identifies the 1050 * new country code so our regdomain config should match. 1051 */ 1052 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 1053 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 1054 se->se_cc[0] != 0 && 1055 (ic->ic_regdomain.country == CTRY_DEFAULT || 1056 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 1057 fail |= MATCH_CC; 1058 } 1059 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 1060 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 1061 fail |= MATCH_PRIVACY; 1062 } else { 1063 /* XXX does this mean privacy is supported or required? */ 1064 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 1065 fail |= MATCH_PRIVACY; 1066 } 1067 se0->se_flags &= ~STA_DEMOTE11B; 1068 rate = check_rate(vap, se->se_chan, se); 1069 if (rate & IEEE80211_RATE_BASIC) { 1070 fail |= MATCH_RATE; 1071 /* 1072 * An 11b-only ap will give a rate mismatch if there is an 1073 * OFDM fixed tx rate for 11g. Try downgrading the channel 1074 * in the scan list to 11b and retry the rate check. 1075 */ 1076 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 1077 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 1078 if ((rate & IEEE80211_RATE_BASIC) == 0) { 1079 fail &= ~MATCH_RATE; 1080 se0->se_flags |= STA_DEMOTE11B; 1081 } 1082 } 1083 } else if (rate < 2*24) { 1084 /* 1085 * This is an 11b-only ap. Check the desired mode in 1086 * case that needs to be honored (mode 11g filters out 1087 * 11b-only ap's). Otherwise force any 11g channel used 1088 * in scanning to be demoted. 1089 * 1090 * NB: we cheat a bit here by looking at the max rate; 1091 * we could/should check the rates. 1092 */ 1093 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 1094 vap->iv_des_mode == IEEE80211_MODE_11B)) 1095 fail |= MATCH_RATE; 1096 else 1097 se0->se_flags |= STA_DEMOTE11B; 1098 } 1099 if (ss->ss_nssid != 0 && 1100 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 1101 fail |= MATCH_SSID; 1102 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 1103 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 1104 fail |= MATCH_BSSID; 1105 if (se0->se_fails >= STA_FAILS_MAX) 1106 fail |= MATCH_FAILS; 1107 if (se0->se_notseen >= STA_PURGE_SCANS) 1108 fail |= MATCH_NOTSEEN; 1109 if (se->se_rssi < STA_RSSI_MIN) 1110 fail |= MATCH_RSSI; 1111#ifdef IEEE80211_DEBUG 1112 if (ieee80211_msg(vap, debug)) { 1113 printf(" %c %s", 1114 fail & MATCH_FAILS ? '=' : 1115 fail & MATCH_NOTSEEN ? '^' : 1116 fail & MATCH_CC ? '$' : 1117#ifdef IEEE80211_SUPPORT_TDMA 1118 fail & MATCH_TDMA_NOIE ? '&' : 1119 fail & MATCH_TDMA_VERSION ? 'v' : 1120 fail & MATCH_TDMA_NOTMASTER ? 's' : 1121 fail & MATCH_TDMA_NOSLOT ? 'f' : 1122 fail & MATCH_TDMA_LOCAL ? 'l' : 1123#endif 1124 fail & MATCH_MESH_NOID ? 'm' : 1125 fail ? '-' : '+', ether_sprintf(se->se_macaddr)); 1126 printf(" %s%c", ether_sprintf(se->se_bssid), 1127 fail & MATCH_BSSID ? '!' : ' '); 1128 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 1129 fail & MATCH_CHANNEL ? '!' : ' '); 1130 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 1131 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 1132 fail & MATCH_RATE ? '!' : ' '); 1133 printf(" %4s%c", 1134 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 1135 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", 1136 fail & MATCH_CAPINFO ? '!' : ' '); 1137 printf(" %3s%c ", 1138 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 1139 "wep" : "no", 1140 fail & MATCH_PRIVACY ? '!' : ' '); 1141 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 1142 printf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); 1143 } 1144#endif 1145 return fail; 1146} 1147 1148static void 1149sta_update_notseen(struct sta_table *st) 1150{ 1151 struct sta_entry *se; 1152 1153 IEEE80211_SCAN_TABLE_LOCK(st); 1154 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1155 /* 1156 * If seen the reset and don't bump the count; 1157 * otherwise bump the ``not seen'' count. Note 1158 * that this insures that stations for which we 1159 * see frames while not scanning but not during 1160 * this scan will not be penalized. 1161 */ 1162 if (se->se_seen) 1163 se->se_seen = 0; 1164 else 1165 se->se_notseen++; 1166 } 1167 IEEE80211_SCAN_TABLE_UNLOCK(st); 1168} 1169 1170static void 1171sta_dec_fails(struct sta_table *st) 1172{ 1173 struct sta_entry *se; 1174 1175 IEEE80211_SCAN_TABLE_LOCK(st); 1176 TAILQ_FOREACH(se, &st->st_entry, se_list) 1177 if (se->se_fails) 1178 se->se_fails--; 1179 IEEE80211_SCAN_TABLE_UNLOCK(st); 1180} 1181 1182static struct sta_entry * 1183select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1184{ 1185 struct sta_table *st = ss->ss_priv; 1186 struct sta_entry *se, *selbs = NULL; 1187 1188 IEEE80211_DPRINTF(vap, debug, " %s\n", 1189 "macaddr bssid chan rssi rate flag wep essid"); 1190 IEEE80211_SCAN_TABLE_LOCK(st); 1191 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1192 ieee80211_ies_expand(&se->base.se_ies); 1193 if (match_bss(vap, ss, se, debug) == 0) { 1194 if (selbs == NULL) 1195 selbs = se; 1196 else if (sta_compare(se, selbs) > 0) 1197 selbs = se; 1198 } 1199 } 1200 IEEE80211_SCAN_TABLE_UNLOCK(st); 1201 1202 return selbs; 1203} 1204 1205/* 1206 * Pick an ap or ibss network to join or find a channel 1207 * to use to start an ibss network. 1208 */ 1209static int 1210sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1211{ 1212 struct sta_table *st = ss->ss_priv; 1213 struct sta_entry *selbs; 1214 struct ieee80211_channel *chan; 1215 1216 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1217 ("wrong mode %u", vap->iv_opmode)); 1218 1219 if (st->st_newscan) { 1220 sta_update_notseen(st); 1221 st->st_newscan = 0; 1222 } 1223 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1224 /* 1225 * Manual/background scan, don't select+join the 1226 * bss, just return. The scanning framework will 1227 * handle notification that this has completed. 1228 */ 1229 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1230 return 1; 1231 } 1232 /* 1233 * Automatic sequencing; look for a candidate and 1234 * if found join the network. 1235 */ 1236 /* NB: unlocked read should be ok */ 1237 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1238 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1239 "%s: no scan candidate\n", __func__); 1240 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1241 return 0; 1242notfound: 1243 /* 1244 * If nothing suitable was found decrement 1245 * the failure counts so entries will be 1246 * reconsidered the next time around. We 1247 * really want to do this only for sta's 1248 * where we've previously had some success. 1249 */ 1250 sta_dec_fails(st); 1251 st->st_newscan = 1; 1252 return 0; /* restart scan */ 1253 } 1254 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1255 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1256 return (selbs != NULL); 1257 if (selbs == NULL) 1258 goto notfound; 1259 chan = selbs->base.se_chan; 1260 if (selbs->se_flags & STA_DEMOTE11B) 1261 chan = demote11b(vap, chan); 1262 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1263 goto notfound; 1264 return 1; /* terminate scan */ 1265} 1266 1267/* 1268 * Lookup an entry in the scan cache. We assume we're 1269 * called from the bottom half or such that we don't need 1270 * to block the bottom half so that it's safe to return 1271 * a reference to an entry w/o holding the lock on the table. 1272 */ 1273static struct sta_entry * 1274sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1275{ 1276 struct sta_entry *se; 1277 int hash = STA_HASH(macaddr); 1278 1279 IEEE80211_SCAN_TABLE_LOCK(st); 1280 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1281 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1282 break; 1283 IEEE80211_SCAN_TABLE_UNLOCK(st); 1284 1285 return se; /* NB: unlocked */ 1286} 1287 1288static void 1289sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1290{ 1291 struct ieee80211com *ic = vap->iv_ic; 1292 struct ieee80211_node *ni = vap->iv_bss; 1293 struct sta_table *st = ss->ss_priv; 1294 enum ieee80211_phymode mode; 1295 struct sta_entry *se, *selbs; 1296 uint8_t roamRate, curRate, ucastRate; 1297 int8_t roamRssi, curRssi; 1298 1299 se = sta_lookup(st, ni->ni_macaddr); 1300 if (se == NULL) { 1301 /* XXX something is wrong */ 1302 return; 1303 } 1304 1305 mode = ieee80211_chan2mode(ic->ic_bsschan); 1306 roamRate = vap->iv_roamparms[mode].rate; 1307 roamRssi = vap->iv_roamparms[mode].rssi; 1308 ucastRate = vap->iv_txparms[mode].ucastrate; 1309 /* NB: the most up to date rssi is in the node, not the scan cache */ 1310 curRssi = ic->ic_node_getrssi(ni); 1311 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1312 curRate = ni->ni_txrate; 1313 roamRate &= IEEE80211_RATE_VAL; 1314 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1315 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1316 __func__, curRssi, curRate, roamRssi, roamRate); 1317 } else { 1318 curRate = roamRate; /* NB: insure compare below fails */ 1319 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1320 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1321 } 1322 /* 1323 * Check if a new ap should be used and switch. 1324 * XXX deauth current ap 1325 */ 1326 if (curRate < roamRate || curRssi < roamRssi) { 1327 if (ieee80211_time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1328 /* 1329 * Scan cache contents are too old; force a scan now 1330 * if possible so we have current state to make a 1331 * decision with. We don't kick off a bg scan if 1332 * we're using dynamic turbo and boosted or if the 1333 * channel is busy. 1334 * XXX force immediate switch on scan complete 1335 */ 1336 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1337 ieee80211_time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) 1338 ieee80211_bg_scan(vap, 0); 1339 return; 1340 } 1341 se->base.se_rssi = curRssi; 1342 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1343 if (selbs != NULL && selbs != se) { 1344 struct ieee80211_channel *chan; 1345 1346 IEEE80211_DPRINTF(vap, 1347 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1348 "%s: ROAM: curRate %u, roamRate %u, " 1349 "curRssi %d, roamRssi %d\n", __func__, 1350 curRate, roamRate, curRssi, roamRssi); 1351 1352 chan = selbs->base.se_chan; 1353 if (selbs->se_flags & STA_DEMOTE11B) 1354 chan = demote11b(vap, chan); 1355 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1356 } 1357 } 1358} 1359 1360/* 1361 * Age entries in the scan cache. 1362 * XXX also do roaming since it's convenient 1363 */ 1364static void 1365sta_age(struct ieee80211_scan_state *ss) 1366{ 1367 struct ieee80211vap *vap = ss->ss_vap; 1368 1369 adhoc_age(ss); 1370 /* 1371 * If rate control is enabled check periodically to see if 1372 * we should roam from our current connection to one that 1373 * might be better. This only applies when we're operating 1374 * in sta mode and automatic roaming is set. 1375 * XXX defer if busy 1376 * XXX repeater station 1377 * XXX do when !bgscan? 1378 */ 1379 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1380 ("wrong mode %u", vap->iv_opmode)); 1381 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1382 (vap->iv_flags & IEEE80211_F_BGSCAN) && 1383 vap->iv_state >= IEEE80211_S_RUN) 1384 /* XXX vap is implicit */ 1385 sta_roam_check(ss, vap); 1386} 1387 1388/* 1389 * Iterate over the entries in the scan cache, invoking 1390 * the callback function on each one. 1391 */ 1392static void 1393sta_iterate(struct ieee80211_scan_state *ss, 1394 ieee80211_scan_iter_func *f, void *arg) 1395{ 1396 struct sta_table *st = ss->ss_priv; 1397 struct sta_entry *se; 1398 u_int gen; 1399 1400 IEEE80211_SCAN_ITER_LOCK(st); 1401 gen = st->st_scaniter++; 1402restart: 1403 IEEE80211_SCAN_TABLE_LOCK(st); 1404 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1405 if (se->se_scangen != gen) { 1406 se->se_scangen = gen; 1407 /* update public state */ 1408 se->base.se_age = ticks - se->se_lastupdate; 1409 IEEE80211_SCAN_TABLE_UNLOCK(st); 1410 (*f)(arg, &se->base); 1411 goto restart; 1412 } 1413 } 1414 IEEE80211_SCAN_TABLE_UNLOCK(st); 1415 1416 IEEE80211_SCAN_ITER_UNLOCK(st); 1417} 1418 1419static void 1420sta_assoc_fail(struct ieee80211_scan_state *ss, 1421 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1422{ 1423 struct sta_table *st = ss->ss_priv; 1424 struct sta_entry *se; 1425 1426 se = sta_lookup(st, macaddr); 1427 if (se != NULL) { 1428 se->se_fails++; 1429 se->se_lastfail = ticks; 1430 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1431 macaddr, "%s: reason %u fails %u", 1432 __func__, reason, se->se_fails); 1433 } 1434} 1435 1436static void 1437sta_assoc_success(struct ieee80211_scan_state *ss, 1438 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1439{ 1440 struct sta_table *st = ss->ss_priv; 1441 struct sta_entry *se; 1442 1443 se = sta_lookup(st, macaddr); 1444 if (se != NULL) { 1445#if 0 1446 se->se_fails = 0; 1447 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1448 macaddr, "%s: fails %u", 1449 __func__, se->se_fails); 1450#endif 1451 se->se_lastassoc = ticks; 1452 } 1453} 1454 1455static const struct ieee80211_scanner sta_default = { 1456 .scan_name = "default", 1457 .scan_attach = sta_attach, 1458 .scan_detach = sta_detach, 1459 .scan_start = sta_start, 1460 .scan_restart = sta_restart, 1461 .scan_cancel = sta_cancel, 1462 .scan_end = sta_pick_bss, 1463 .scan_flush = sta_flush, 1464 .scan_add = sta_add, 1465 .scan_age = sta_age, 1466 .scan_iterate = sta_iterate, 1467 .scan_assoc_fail = sta_assoc_fail, 1468 .scan_assoc_success = sta_assoc_success, 1469}; 1470IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); 1471 1472/* 1473 * Adhoc mode-specific support. 1474 */ 1475 1476static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1477{ 5180, 5200, 5220, 5240 }; 1478static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1479{ 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1480static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1481{ 5170, 5190, 5210, 5230 }; 1482static const uint16_t adhoc11b[] = /* 10, 11 */ 1483{ 2457, 2462 }; 1484 1485static const struct scanlist adhocScanTable[] = { 1486 { IEEE80211_MODE_11B, X(adhoc11b) }, 1487 { IEEE80211_MODE_11A, X(adhocWorld) }, 1488 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1489 { IEEE80211_MODE_11B, X(adhocMkk) }, 1490 { .list = NULL } 1491}; 1492#undef X 1493 1494/* 1495 * Start an adhoc-mode scan by populating the channel list. 1496 */ 1497static int 1498adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1499{ 1500 struct sta_table *st = ss->ss_priv; 1501 1502 makescanlist(ss, vap, adhocScanTable); 1503 1504 if (ss->ss_mindwell == 0) 1505 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1506 if (ss->ss_maxdwell == 0) 1507 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1508 1509 st->st_scangen++; 1510 st->st_newscan = 1; 1511 1512 return 0; 1513} 1514 1515/* 1516 * Select a channel to start an adhoc network on. 1517 * The channel list was populated with appropriate 1518 * channels so select one that looks least occupied. 1519 */ 1520static struct ieee80211_channel * 1521adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1522{ 1523 struct sta_table *st = ss->ss_priv; 1524 struct sta_entry *se; 1525 struct ieee80211_channel *c, *bestchan; 1526 int i, bestrssi, maxrssi; 1527 1528 bestchan = NULL; 1529 bestrssi = -1; 1530 1531 IEEE80211_SCAN_TABLE_LOCK(st); 1532 for (i = 0; i < ss->ss_last; i++) { 1533 c = ss->ss_chans[i]; 1534 /* never consider a channel with radar */ 1535 if (IEEE80211_IS_CHAN_RADAR(c)) 1536 continue; 1537 /* skip channels disallowed by regulatory settings */ 1538 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1539 continue; 1540 /* check channel attributes for band compatibility */ 1541 if (flags != 0 && (c->ic_flags & flags) != flags) 1542 continue; 1543 maxrssi = 0; 1544 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1545 if (se->base.se_chan != c) 1546 continue; 1547 if (se->base.se_rssi > maxrssi) 1548 maxrssi = se->base.se_rssi; 1549 } 1550 if (bestchan == NULL || maxrssi < bestrssi) 1551 bestchan = c; 1552 } 1553 IEEE80211_SCAN_TABLE_UNLOCK(st); 1554 1555 return bestchan; 1556} 1557 1558/* 1559 * Pick an ibss network to join or find a channel 1560 * to use to start an ibss network. 1561 */ 1562static int 1563adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1564{ 1565 struct sta_table *st = ss->ss_priv; 1566 struct sta_entry *selbs; 1567 struct ieee80211_channel *chan; 1568 struct ieee80211com *ic = vap->iv_ic; 1569 1570 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1571 vap->iv_opmode == IEEE80211_M_AHDEMO || 1572 vap->iv_opmode == IEEE80211_M_MBSS, 1573 ("wrong opmode %u", vap->iv_opmode)); 1574 1575 if (st->st_newscan) { 1576 sta_update_notseen(st); 1577 st->st_newscan = 0; 1578 } 1579 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1580 /* 1581 * Manual/background scan, don't select+join the 1582 * bss, just return. The scanning framework will 1583 * handle notification that this has completed. 1584 */ 1585 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1586 return 1; 1587 } 1588 /* 1589 * Automatic sequencing; look for a candidate and 1590 * if found join the network. 1591 */ 1592 /* NB: unlocked read should be ok */ 1593 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1594 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1595 "%s: no scan candidate\n", __func__); 1596 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1597 return 0; 1598notfound: 1599 /* NB: never auto-start a tdma network for slot !0 */ 1600#ifdef IEEE80211_SUPPORT_TDMA 1601 if (vap->iv_des_nssid && 1602 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || 1603 ieee80211_tdma_getslot(vap) == 0)) { 1604#else 1605 if (vap->iv_des_nssid) { 1606#endif 1607 /* 1608 * No existing adhoc network to join and we have 1609 * an ssid; start one up. If no channel was 1610 * specified, try to select a channel. 1611 */ 1612 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1613 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1614 chan = adhoc_pick_channel(ss, 0); 1615 } else 1616 chan = vap->iv_des_chan; 1617 if (chan != NULL) { 1618 struct ieee80211com *ic = vap->iv_ic; 1619 /* 1620 * Create a HT capable IBSS; the per-node 1621 * probe request/response will result in 1622 * "correct" rate control capabilities being 1623 * negotiated. 1624 */ 1625 chan = ieee80211_ht_adjust_channel(ic, 1626 chan, vap->iv_flags_ht); 1627 ieee80211_create_ibss(vap, chan); 1628 return 1; 1629 } 1630 } 1631 /* 1632 * If nothing suitable was found decrement 1633 * the failure counts so entries will be 1634 * reconsidered the next time around. We 1635 * really want to do this only for sta's 1636 * where we've previously had some success. 1637 */ 1638 sta_dec_fails(st); 1639 st->st_newscan = 1; 1640 return 0; /* restart scan */ 1641 } 1642 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1643 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1644 return (selbs != NULL); 1645 if (selbs == NULL) 1646 goto notfound; 1647 chan = selbs->base.se_chan; 1648 if (selbs->se_flags & STA_DEMOTE11B) 1649 chan = demote11b(vap, chan); 1650 /* 1651 * If HT is available, make it a possibility here. 1652 * The intent is to enable HT20/HT40 when joining a non-HT 1653 * IBSS node; we can then advertise HT IEs and speak HT 1654 * to any subsequent nodes that support it. 1655 */ 1656 chan = ieee80211_ht_adjust_channel(ic, 1657 chan, vap->iv_flags_ht); 1658 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1659 goto notfound; 1660 return 1; /* terminate scan */ 1661} 1662 1663/* 1664 * Age entries in the scan cache. 1665 */ 1666static void 1667adhoc_age(struct ieee80211_scan_state *ss) 1668{ 1669 struct sta_table *st = ss->ss_priv; 1670 struct sta_entry *se, *next; 1671 1672 IEEE80211_SCAN_TABLE_LOCK(st); 1673 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 1674 if (se->se_notseen > STA_PURGE_SCANS) { 1675 TAILQ_REMOVE(&st->st_entry, se, se_list); 1676 LIST_REMOVE(se, se_hash); 1677 ieee80211_ies_cleanup(&se->base.se_ies); 1678 IEEE80211_FREE(se, M_80211_SCAN); 1679 } 1680 } 1681 IEEE80211_SCAN_TABLE_UNLOCK(st); 1682} 1683 1684static const struct ieee80211_scanner adhoc_default = { 1685 .scan_name = "default", 1686 .scan_attach = sta_attach, 1687 .scan_detach = sta_detach, 1688 .scan_start = adhoc_start, 1689 .scan_restart = sta_restart, 1690 .scan_cancel = sta_cancel, 1691 .scan_end = adhoc_pick_bss, 1692 .scan_flush = sta_flush, 1693 .scan_pickchan = adhoc_pick_channel, 1694 .scan_add = sta_add, 1695 .scan_age = adhoc_age, 1696 .scan_iterate = sta_iterate, 1697 .scan_assoc_fail = sta_assoc_fail, 1698 .scan_assoc_success = sta_assoc_success, 1699}; 1700IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1701IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1702 1703static int 1704ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1705{ 1706 struct sta_table *st = ss->ss_priv; 1707 1708 makescanlist(ss, vap, staScanTable); 1709 1710 if (ss->ss_mindwell == 0) 1711 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1712 if (ss->ss_maxdwell == 0) 1713 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1714 1715 st->st_scangen++; 1716 st->st_newscan = 1; 1717 1718 return 0; 1719} 1720 1721/* 1722 * Cancel an ongoing scan. 1723 */ 1724static int 1725ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1726{ 1727 return 0; 1728} 1729 1730/* 1731 * Pick a quiet channel to use for ap operation. 1732 */ 1733static struct ieee80211_channel * 1734ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1735{ 1736 struct sta_table *st = ss->ss_priv; 1737 struct ieee80211_channel *bestchan = NULL; 1738 int i; 1739 1740 /* XXX select channel more intelligently, e.g. channel spread, power */ 1741 /* NB: use scan list order to preserve channel preference */ 1742 for (i = 0; i < ss->ss_last; i++) { 1743 struct ieee80211_channel *chan = ss->ss_chans[i]; 1744 /* 1745 * If the channel is unoccupied the max rssi 1746 * should be zero; just take it. Otherwise 1747 * track the channel with the lowest rssi and 1748 * use that when all channels appear occupied. 1749 */ 1750 if (IEEE80211_IS_CHAN_RADAR(chan)) 1751 continue; 1752 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1753 continue; 1754 /* check channel attributes for band compatibility */ 1755 if (flags != 0 && (chan->ic_flags & flags) != flags) 1756 continue; 1757 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); 1758 /* XXX channel have interference */ 1759 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1760 /* XXX use other considerations */ 1761 return chan; 1762 } 1763 if (bestchan == NULL || 1764 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1765 bestchan = chan; 1766 } 1767 return bestchan; 1768} 1769 1770/* 1771 * Pick a quiet channel to use for ap operation. 1772 */ 1773static int 1774ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1775{ 1776 struct ieee80211com *ic = vap->iv_ic; 1777 struct ieee80211_channel *bestchan; 1778 1779 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1780 ("wrong opmode %u", vap->iv_opmode)); 1781 bestchan = ap_pick_channel(ss, 0); 1782 if (bestchan == NULL) { 1783 /* no suitable channel, should not happen */ 1784 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1785 "%s: no suitable channel! (should not happen)\n", __func__); 1786 /* XXX print something? */ 1787 return 0; /* restart scan */ 1788 } 1789 /* 1790 * If this is a dynamic turbo channel, start with the unboosted one. 1791 */ 1792 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1793 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1794 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1795 if (bestchan == NULL) { 1796 /* should never happen ?? */ 1797 return 0; 1798 } 1799 } 1800 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1801 /* 1802 * Manual/background scan, don't select+join the 1803 * bss, just return. The scanning framework will 1804 * handle notification that this has completed. 1805 */ 1806 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1807 return 1; 1808 } 1809 ieee80211_create_ibss(vap, 1810 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht)); 1811 return 1; 1812} 1813 1814static const struct ieee80211_scanner ap_default = { 1815 .scan_name = "default", 1816 .scan_attach = sta_attach, 1817 .scan_detach = sta_detach, 1818 .scan_start = ap_start, 1819 .scan_restart = sta_restart, 1820 .scan_cancel = ap_cancel, 1821 .scan_end = ap_end, 1822 .scan_flush = sta_flush, 1823 .scan_pickchan = ap_pick_channel, 1824 .scan_add = sta_add, 1825 .scan_age = adhoc_age, 1826 .scan_iterate = sta_iterate, 1827 .scan_assoc_success = sta_assoc_success, 1828 .scan_assoc_fail = sta_assoc_fail, 1829}; 1830IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1831 1832#ifdef IEEE80211_SUPPORT_MESH 1833/* 1834 * Pick an mbss network to join or find a channel 1835 * to use to start an mbss network. 1836 */ 1837static int 1838mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1839{ 1840 struct sta_table *st = ss->ss_priv; 1841 struct ieee80211_mesh_state *ms = vap->iv_mesh; 1842 struct sta_entry *selbs; 1843 struct ieee80211_channel *chan; 1844 1845 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, 1846 ("wrong opmode %u", vap->iv_opmode)); 1847 1848 if (st->st_newscan) { 1849 sta_update_notseen(st); 1850 st->st_newscan = 0; 1851 } 1852 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1853 /* 1854 * Manual/background scan, don't select+join the 1855 * bss, just return. The scanning framework will 1856 * handle notification that this has completed. 1857 */ 1858 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1859 return 1; 1860 } 1861 /* 1862 * Automatic sequencing; look for a candidate and 1863 * if found join the network. 1864 */ 1865 /* NB: unlocked read should be ok */ 1866 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1867 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1868 "%s: no scan candidate\n", __func__); 1869 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1870 return 0; 1871notfound: 1872 if (ms->ms_idlen != 0) { 1873 /* 1874 * No existing mbss network to join and we have 1875 * a meshid; start one up. If no channel was 1876 * specified, try to select a channel. 1877 */ 1878 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1879 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1880 struct ieee80211com *ic = vap->iv_ic; 1881 1882 chan = adhoc_pick_channel(ss, 0); 1883 if (chan != NULL) 1884 chan = ieee80211_ht_adjust_channel(ic, 1885 chan, vap->iv_flags_ht); 1886 } else 1887 chan = vap->iv_des_chan; 1888 if (chan != NULL) { 1889 ieee80211_create_ibss(vap, chan); 1890 return 1; 1891 } 1892 } 1893 /* 1894 * If nothing suitable was found decrement 1895 * the failure counts so entries will be 1896 * reconsidered the next time around. We 1897 * really want to do this only for sta's 1898 * where we've previously had some success. 1899 */ 1900 sta_dec_fails(st); 1901 st->st_newscan = 1; 1902 return 0; /* restart scan */ 1903 } 1904 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1905 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1906 return (selbs != NULL); 1907 if (selbs == NULL) 1908 goto notfound; 1909 chan = selbs->base.se_chan; 1910 if (selbs->se_flags & STA_DEMOTE11B) 1911 chan = demote11b(vap, chan); 1912 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1913 goto notfound; 1914 return 1; /* terminate scan */ 1915} 1916 1917static const struct ieee80211_scanner mesh_default = { 1918 .scan_name = "default", 1919 .scan_attach = sta_attach, 1920 .scan_detach = sta_detach, 1921 .scan_start = adhoc_start, 1922 .scan_restart = sta_restart, 1923 .scan_cancel = sta_cancel, 1924 .scan_end = mesh_pick_bss, 1925 .scan_flush = sta_flush, 1926 .scan_pickchan = adhoc_pick_channel, 1927 .scan_add = sta_add, 1928 .scan_age = adhoc_age, 1929 .scan_iterate = sta_iterate, 1930 .scan_assoc_fail = sta_assoc_fail, 1931 .scan_assoc_success = sta_assoc_success, 1932}; 1933IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); 1934#endif /* IEEE80211_SUPPORT_MESH */ 1935