1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include <sys/cdefs.h> 29 __FBSDID("$FreeBSD$"); 30 31 /* 32 * IEEE 802.11 station scanning support. 33 */ 34 #include "opt_wlan.h" 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/endian.h> 40 #include <sys/malloc.h> 41 #include <sys/module.h> 42 43 #include <sys/socket.h> 44 45 #include <net/if.h> 46 #include <net/if_var.h> 47 #include <net/if_media.h> 48 #include <net/ethernet.h> 49 50 #include <net80211/ieee80211_var.h> 51 #include <net80211/ieee80211_input.h> 52 #include <net80211/ieee80211_regdomain.h> 53 #ifdef IEEE80211_SUPPORT_TDMA 54 #include <net80211/ieee80211_tdma.h> 55 #endif 56 #ifdef IEEE80211_SUPPORT_MESH 57 #include <net80211/ieee80211_mesh.h> 58 #endif 59 #include <net80211/ieee80211_ratectl.h> 60 #include <net80211/ieee80211_vht.h> 61 62 #include <net/bpf.h> 63 64 /* 65 * Parameters for managing cache entries: 66 * 67 * o a station with STA_FAILS_MAX failures is not considered 68 * when picking a candidate 69 * o a station that hasn't had an update in STA_PURGE_SCANS 70 * (background) scans is discarded 71 * o after STA_FAILS_AGE seconds we clear the failure count 72 */ 73 #define STA_FAILS_MAX 2 /* assoc failures before ignored */ 74 #define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ 75 #define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ 76 77 /* XXX tunable */ 78 #define STA_RSSI_MIN 8 /* min acceptable rssi */ 79 #define STA_RSSI_MAX 40 /* max rssi for comparison */ 80 81 struct sta_entry { 82 struct ieee80211_scan_entry base; 83 TAILQ_ENTRY(sta_entry) se_list; 84 LIST_ENTRY(sta_entry) se_hash; 85 uint8_t se_fails; /* failure to associate count */ 86 uint8_t se_seen; /* seen during current scan */ 87 uint8_t se_notseen; /* not seen in previous scans */ 88 uint8_t se_flags; 89 #define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ 90 uint32_t se_avgrssi; /* LPF rssi state */ 91 unsigned long se_lastupdate; /* time of last update */ 92 unsigned long se_lastfail; /* time of last failure */ 93 unsigned long se_lastassoc; /* time of last association */ 94 u_int se_scangen; /* iterator scan gen# */ 95 u_int se_countrygen; /* gen# of last cc notify */ 96 }; 97 98 #define STA_HASHSIZE 32 99 /* simple hash is enough for variation of macaddr */ 100 #define STA_HASH(addr) \ 101 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) 102 103 #define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */ 104 CTASSERT(MAX_IEEE_CHAN >= 256); 105 106 struct sta_table { 107 ieee80211_scan_table_lock_t st_lock; /* on scan table */ 108 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 109 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 110 ieee80211_scan_iter_lock_t st_scanlock; /* on st_scaniter */ 111 u_int st_scaniter; /* gen# for iterator */ 112 u_int st_scangen; /* scan generation # */ 113 int st_newscan; 114 /* ap-related state */ 115 int st_maxrssi[MAX_IEEE_CHAN]; 116 }; 117 118 static void sta_flush_table(struct sta_table *); 119 /* 120 * match_bss returns a bitmask describing if an entry is suitable 121 * for use. If non-zero the entry was deemed not suitable and it's 122 * contents explains why. The following flags are or'd to this 123 * mask and can be used to figure out why the entry was rejected. 124 */ 125 #define MATCH_CHANNEL 0x00001 /* channel mismatch */ 126 #define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ 127 #define MATCH_PRIVACY 0x00004 /* privacy mismatch */ 128 #define MATCH_RATE 0x00008 /* rate set mismatch */ 129 #define MATCH_SSID 0x00010 /* ssid mismatch */ 130 #define MATCH_BSSID 0x00020 /* bssid mismatch */ 131 #define MATCH_FAILS 0x00040 /* too many failed auth attempts */ 132 #define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ 133 #define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ 134 #define MATCH_CC 0x00200 /* country code mismatch */ 135 #ifdef IEEE80211_SUPPORT_TDMA 136 #define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ 137 #define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ 138 #define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ 139 #define MATCH_TDMA_LOCAL 0x02000 /* local address */ 140 #define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ 141 #endif 142 #define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ 143 #define MATCH_MESHID 0x20000 /* meshid mismatch */ 144 static int match_bss(struct ieee80211vap *, 145 const struct ieee80211_scan_state *, struct sta_entry *, int); 146 static void adhoc_age(struct ieee80211_scan_state *); 147 148 static __inline int 149 isocmp(const uint8_t cc1[], const uint8_t cc2[]) 150 { 151 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 152 } 153 154 /* number of references from net80211 layer */ 155 static int nrefs = 0; 156 /* 157 * Module glue. 158 */ 159 IEEE80211_SCANNER_MODULE(sta, 1); 160 161 /* 162 * Attach prior to any scanning work. 163 */ 164 static int 165 sta_attach(struct ieee80211_scan_state *ss) 166 { 167 struct sta_table *st; 168 169 st = (struct sta_table *) IEEE80211_MALLOC(sizeof(struct sta_table), 170 M_80211_SCAN, 171 IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 172 if (st == NULL) 173 return 0; 174 IEEE80211_SCAN_TABLE_LOCK_INIT(st, "scantable"); 175 IEEE80211_SCAN_ITER_LOCK_INIT(st, "scangen"); 176 TAILQ_INIT(&st->st_entry); 177 ss->ss_priv = st; 178 nrefs++; /* NB: we assume caller locking */ 179 return 1; 180 } 181 182 /* 183 * Cleanup any private state. 184 */ 185 static int 186 sta_detach(struct ieee80211_scan_state *ss) 187 { 188 struct sta_table *st = ss->ss_priv; 189 190 if (st != NULL) { 191 sta_flush_table(st); 192 IEEE80211_SCAN_TABLE_LOCK_DESTROY(st); 193 IEEE80211_SCAN_ITER_LOCK_DESTROY(st); 194 IEEE80211_FREE(st, M_80211_SCAN); 195 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 196 nrefs--; /* NB: we assume caller locking */ 197 } 198 return 1; 199 } 200 201 /* 202 * Flush all per-scan state. 203 */ 204 static int 205 sta_flush(struct ieee80211_scan_state *ss) 206 { 207 struct sta_table *st = ss->ss_priv; 208 209 IEEE80211_SCAN_TABLE_LOCK(st); 210 sta_flush_table(st); 211 IEEE80211_SCAN_TABLE_UNLOCK(st); 212 ss->ss_last = 0; 213 return 0; 214 } 215 216 /* 217 * Flush all entries in the scan cache. 218 */ 219 static void 220 sta_flush_table(struct sta_table *st) 221 { 222 struct sta_entry *se, *next; 223 224 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 225 TAILQ_REMOVE(&st->st_entry, se, se_list); 226 LIST_REMOVE(se, se_hash); 227 ieee80211_ies_cleanup(&se->base.se_ies); 228 IEEE80211_FREE(se, M_80211_SCAN); 229 } 230 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 231 } 232 233 /* 234 * Process a beacon or probe response frame; create an 235 * entry in the scan cache or update any previous entry. 236 */ 237 static int 238 sta_add(struct ieee80211_scan_state *ss, 239 struct ieee80211_channel *curchan, 240 const struct ieee80211_scanparams *sp, 241 const struct ieee80211_frame *wh, 242 int subtype, int rssi, int noise) 243 { 244 #define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 245 #define PICK1ST(_ss) \ 246 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 247 IEEE80211_SCAN_PICK1ST) 248 struct sta_table *st = ss->ss_priv; 249 const uint8_t *macaddr = wh->i_addr2; 250 struct ieee80211vap *vap = ss->ss_vap; 251 struct ieee80211com *ic = vap->iv_ic; 252 struct ieee80211_channel *c; 253 struct sta_entry *se; 254 struct ieee80211_scan_entry *ise; 255 int hash; 256 257 hash = STA_HASH(macaddr); 258 259 IEEE80211_SCAN_TABLE_LOCK(st); 260 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 261 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 262 goto found; 263 se = (struct sta_entry *) IEEE80211_MALLOC(sizeof(struct sta_entry), 264 M_80211_SCAN, IEEE80211_M_NOWAIT | IEEE80211_M_ZERO); 265 if (se == NULL) { 266 IEEE80211_SCAN_TABLE_UNLOCK(st); 267 return 0; 268 } 269 se->se_scangen = st->st_scaniter-1; 270 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 271 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 272 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 273 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 274 found: 275 ise = &se->base; 276 /* XXX ap beaconing multiple ssid w/ same bssid */ 277 if (sp->ssid[1] != 0 && 278 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 279 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 280 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 281 ("rate set too large: %u", sp->rates[1])); 282 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 283 if (sp->xrates != NULL) { 284 /* XXX validate xrates[1] */ 285 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 286 ("xrate set too large: %u", sp->xrates[1])); 287 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 288 } else 289 ise->se_xrates[1] = 0; 290 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 291 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 292 /* 293 * Record rssi data using extended precision LPF filter. 294 * 295 * NB: use only on-channel data to insure we get a good 296 * estimate of the signal we'll see when associated. 297 */ 298 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 299 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 300 ise->se_noise = noise; 301 } 302 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 303 ise->se_intval = sp->bintval; 304 ise->se_capinfo = sp->capinfo; 305 #ifdef IEEE80211_SUPPORT_MESH 306 if (sp->meshid != NULL && sp->meshid[1] != 0) 307 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); 308 #endif 309 /* 310 * Beware of overriding se_chan for frames seen 311 * off-channel; this can cause us to attempt an 312 * association on the wrong channel. 313 */ 314 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 315 /* 316 * Off-channel, locate the home/bss channel for the sta 317 * using the value broadcast in the DSPARMS ie. We know 318 * sp->chan has this value because it's used to calculate 319 * IEEE80211_BPARSE_OFFCHAN. 320 */ 321 c = ieee80211_find_channel_byieee(ic, sp->chan, 322 curchan->ic_flags); 323 if (c != NULL) { 324 ise->se_chan = c; 325 } else if (ise->se_chan == NULL) { 326 /* should not happen, pick something */ 327 ise->se_chan = curchan; 328 } 329 } else 330 ise->se_chan = curchan; 331 332 /* VHT demotion */ 333 if (IEEE80211_IS_CHAN_VHT(ise->se_chan) && sp->vhtcap == NULL) { 334 IEEE80211_DPRINTF(vap, IEEE80211_MSG_11N, 335 "%s: demoting VHT->HT %d/0x%08x\n", 336 __func__, ise->se_chan->ic_freq, ise->se_chan->ic_flags); 337 /* Demote legacy networks to a non-VHT channel. */ 338 c = ieee80211_find_channel(ic, ise->se_chan->ic_freq, 339 ise->se_chan->ic_flags & ~IEEE80211_CHAN_VHT); 340 KASSERT(c != NULL, 341 ("no non-VHT channel %u", ise->se_chan->ic_ieee)); 342 ise->se_chan = c; 343 } 344 345 /* HT demotion */ 346 if (IEEE80211_IS_CHAN_HT(ise->se_chan) && sp->htcap == NULL) { 347 /* Demote legacy networks to a non-HT channel. */ 348 IEEE80211_DPRINTF(vap, IEEE80211_MSG_11N, 349 "%s: demoting HT->legacy %d/0x%08x\n", 350 __func__, ise->se_chan->ic_freq, ise->se_chan->ic_flags); 351 c = ieee80211_find_channel(ic, ise->se_chan->ic_freq, 352 ise->se_chan->ic_flags & ~IEEE80211_CHAN_HT); 353 KASSERT(c != NULL, 354 ("no legacy channel %u", ise->se_chan->ic_ieee)); 355 ise->se_chan = c; 356 } 357 358 ise->se_fhdwell = sp->fhdwell; 359 ise->se_fhindex = sp->fhindex; 360 ise->se_erp = sp->erp; 361 ise->se_timoff = sp->timoff; 362 if (sp->tim != NULL) { 363 const struct ieee80211_tim_ie *tim = 364 (const struct ieee80211_tim_ie *) sp->tim; 365 ise->se_dtimperiod = tim->tim_period; 366 } 367 if (sp->country != NULL) { 368 const struct ieee80211_country_ie *cie = 369 (const struct ieee80211_country_ie *) sp->country; 370 /* 371 * If 11d is enabled and we're attempting to join a bss 372 * that advertises it's country code then compare our 373 * current settings to what we fetched from the country ie. 374 * If our country code is unspecified or different then 375 * dispatch an event to user space that identifies the 376 * country code so our regdomain config can be changed. 377 */ 378 /* XXX only for STA mode? */ 379 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 380 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 381 (ic->ic_regdomain.country == CTRY_DEFAULT || 382 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 383 /* only issue one notify event per scan */ 384 if (se->se_countrygen != st->st_scangen) { 385 ieee80211_notify_country(vap, ise->se_bssid, 386 cie->cc); 387 se->se_countrygen = st->st_scangen; 388 } 389 } 390 ise->se_cc[0] = cie->cc[0]; 391 ise->se_cc[1] = cie->cc[1]; 392 } 393 /* NB: no need to setup ie ptrs; they are not (currently) used */ 394 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 395 396 /* clear failure count after STA_FAIL_AGE passes */ 397 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 398 se->se_fails = 0; 399 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 400 "%s: fails %u", __func__, se->se_fails); 401 } 402 403 se->se_lastupdate = ticks; /* update time */ 404 se->se_seen = 1; 405 se->se_notseen = 0; 406 407 KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); 408 if (rssi > st->st_maxrssi[sp->bchan]) 409 st->st_maxrssi[sp->bchan] = rssi; 410 411 IEEE80211_SCAN_TABLE_UNLOCK(st); 412 413 /* 414 * If looking for a quick choice and nothing's 415 * been found check here. 416 */ 417 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 418 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 419 420 return 1; 421 #undef PICK1ST 422 #undef ISPROBE 423 } 424 425 /* 426 * Check if a channel is excluded by user request. 427 */ 428 static int 429 isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 430 { 431 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 432 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 433 c->ic_freq != vap->iv_des_chan->ic_freq)); 434 } 435 436 static struct ieee80211_channel * 437 find11gchannel(struct ieee80211com *ic, int i, int freq) 438 { 439 struct ieee80211_channel *c; 440 int j; 441 442 /* 443 * The normal ordering in the channel list is b channel 444 * immediately followed by g so optimize the search for 445 * this. We'll still do a full search just in case. 446 */ 447 for (j = i+1; j < ic->ic_nchans; j++) { 448 c = &ic->ic_channels[j]; 449 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 450 return c; 451 } 452 for (j = 0; j < i; j++) { 453 c = &ic->ic_channels[j]; 454 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 455 return c; 456 } 457 return NULL; 458 } 459 460 static const u_int chanflags[IEEE80211_MODE_MAX] = { 461 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, 462 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, 463 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, 464 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, 465 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, 466 /* check base channel */ 467 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, 468 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, 469 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, 470 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, 471 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, 472 /* check legacy */ 473 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, 474 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, 475 [IEEE80211_MODE_VHT_5GHZ] = IEEE80211_CHAN_A, 476 [IEEE80211_MODE_VHT_2GHZ] = IEEE80211_CHAN_G, 477 }; 478 479 static void 480 add_channels(struct ieee80211vap *vap, 481 struct ieee80211_scan_state *ss, 482 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 483 { 484 struct ieee80211com *ic = vap->iv_ic; 485 struct ieee80211_channel *c, *cg; 486 u_int modeflags; 487 int i; 488 489 KASSERT(mode < nitems(chanflags), ("Unexpected mode %u", mode)); 490 modeflags = chanflags[mode]; 491 for (i = 0; i < nfreq; i++) { 492 if (ss->ss_last >= IEEE80211_SCAN_MAX) 493 break; 494 495 c = ieee80211_find_channel(ic, freq[i], modeflags); 496 if (c == NULL || isexcluded(vap, c)) 497 continue; 498 if (mode == IEEE80211_MODE_AUTO) { 499 KASSERT(IEEE80211_IS_CHAN_B(c), 500 ("%s: wrong channel for 'auto' mode %u / %u\n", 501 __func__, c->ic_freq, c->ic_flags)); 502 503 /* 504 * XXX special-case 11b/g channels so we select 505 * the g channel if both are present. 506 */ 507 if ((cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 508 c = cg; 509 } 510 ss->ss_chans[ss->ss_last++] = c; 511 } 512 } 513 514 struct scanlist { 515 uint16_t mode; 516 uint16_t count; 517 const uint16_t *list; 518 }; 519 520 static int 521 checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 522 { 523 int i; 524 525 for (; scan->list != NULL; scan++) { 526 for (i = 0; i < scan->count; i++) 527 if (scan->list[i] == c->ic_freq) 528 return 1; 529 } 530 return 0; 531 } 532 533 static int 534 onscanlist(const struct ieee80211_scan_state *ss, 535 const struct ieee80211_channel *c) 536 { 537 int i; 538 539 for (i = 0; i < ss->ss_last; i++) 540 if (ss->ss_chans[i] == c) 541 return 1; 542 return 0; 543 } 544 545 static void 546 sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 547 const struct scanlist table[]) 548 { 549 struct ieee80211com *ic = vap->iv_ic; 550 struct ieee80211_channel *c; 551 int i; 552 553 for (i = 0; i < ic->ic_nchans; i++) { 554 if (ss->ss_last >= IEEE80211_SCAN_MAX) 555 break; 556 557 c = &ic->ic_channels[i]; 558 /* 559 * Ignore dynamic turbo channels; we scan them 560 * in normal mode (i.e. not boosted). Likewise 561 * for HT/VHT channels, they get scanned using 562 * legacy rates. 563 */ 564 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c) || 565 IEEE80211_IS_CHAN_VHT(c)) 566 continue; 567 568 /* 569 * If a desired mode was specified, scan only 570 * channels that satisfy that constraint. 571 */ 572 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 573 vap->iv_des_mode != ieee80211_chan2mode(c)) 574 continue; 575 576 /* 577 * Skip channels excluded by user request. 578 */ 579 if (isexcluded(vap, c)) 580 continue; 581 582 /* 583 * Add the channel unless it is listed in the 584 * fixed scan order tables. This insures we 585 * don't sweep back in channels we filtered out 586 * above. 587 */ 588 if (checktable(table, c)) 589 continue; 590 591 /* Add channel to scanning list. */ 592 ss->ss_chans[ss->ss_last++] = c; 593 } 594 /* 595 * Explicitly add any desired channel if: 596 * - not already on the scan list 597 * - allowed by any desired mode constraint 598 * - there is space in the scan list 599 * This allows the channel to be used when the filtering 600 * mechanisms would otherwise elide it (e.g HT, turbo). 601 */ 602 c = vap->iv_des_chan; 603 if (c != IEEE80211_CHAN_ANYC && 604 !onscanlist(ss, c) && 605 (vap->iv_des_mode == IEEE80211_MODE_AUTO || 606 vap->iv_des_mode == ieee80211_chan2mode(c)) && 607 ss->ss_last < IEEE80211_SCAN_MAX) 608 ss->ss_chans[ss->ss_last++] = c; 609 } 610 611 static void 612 makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 613 const struct scanlist table[]) 614 { 615 const struct scanlist *scan; 616 enum ieee80211_phymode mode; 617 618 ss->ss_last = 0; 619 /* 620 * Use the table of ordered channels to construct the list 621 * of channels for scanning. Any channels in the ordered 622 * list not in the master list will be discarded. 623 */ 624 for (scan = table; scan->list != NULL; scan++) { 625 mode = scan->mode; 626 627 switch (mode) { 628 case IEEE80211_MODE_11B: 629 if (vap->iv_des_mode == IEEE80211_MODE_11B) 630 break; 631 632 /* 633 * The scan table marks 2.4Ghz channels as b 634 * so if the desired mode is 11g / 11ng / 11acg, 635 * then use the 11b channel list but upgrade the mode. 636 * 637 * NB: 11b -> AUTO lets add_channels upgrade an 638 * 11b channel to 11g if available. 639 */ 640 if (vap->iv_des_mode == IEEE80211_MODE_AUTO || 641 vap->iv_des_mode == IEEE80211_MODE_11G || 642 vap->iv_des_mode == IEEE80211_MODE_11NG || 643 vap->iv_des_mode == IEEE80211_MODE_VHT_2GHZ) { 644 mode = vap->iv_des_mode; 645 break; 646 } 647 648 continue; 649 case IEEE80211_MODE_11A: 650 /* Use 11a channel list for 11na / 11ac modes */ 651 if (vap->iv_des_mode == IEEE80211_MODE_11NA || 652 vap->iv_des_mode == IEEE80211_MODE_VHT_5GHZ) { 653 mode = vap->iv_des_mode; 654 break; 655 } 656 657 /* FALLTHROUGH */ 658 default: 659 /* 660 * If a desired mode was specified, scan only 661 * channels that satisfy that constraint. 662 */ 663 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 664 vap->iv_des_mode != mode) 665 continue; 666 } 667 668 #ifdef IEEE80211_F_XR 669 /* XR does not operate on turbo channels */ 670 if ((vap->iv_flags & IEEE80211_F_XR) && 671 (mode == IEEE80211_MODE_TURBO_A || 672 mode == IEEE80211_MODE_TURBO_G || 673 mode == IEEE80211_MODE_STURBO_A)) 674 continue; 675 #endif 676 /* 677 * Add the list of the channels; any that are not 678 * in the master channel list will be discarded. 679 */ 680 add_channels(vap, ss, mode, scan->list, scan->count); 681 } 682 683 /* 684 * Add the channels from the ic that are not present 685 * in the table. 686 */ 687 sweepchannels(ss, vap, table); 688 } 689 690 static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 691 { 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 692 static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 693 { 5170, 5190, 5210, 5230 }; 694 static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 695 { 2412, 2437, 2462, 2442, 2472 }; 696 static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 697 { 5745, 5765, 5785, 5805, 5825 }; 698 static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 699 { 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 700 static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 701 { 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 702 static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 703 { 2484 }; 704 static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 705 { 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 706 static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 707 { 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 708 #ifdef ATH_TURBO_SCAN 709 static const uint16_t rcl5[] = /* 3 static turbo channels */ 710 { 5210, 5250, 5290 }; 711 static const uint16_t rcl6[] = /* 2 static turbo channels */ 712 { 5760, 5800 }; 713 static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 714 { 5540, 5580, 5620, 5660 }; 715 static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 716 { 2437 }; 717 static const uint16_t rcl13[] = /* dynamic Turbo channels */ 718 { 5200, 5240, 5280, 5765, 5805 }; 719 #endif /* ATH_TURBO_SCAN */ 720 721 #define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 722 723 static const struct scanlist staScanTable[] = { 724 { IEEE80211_MODE_11B, X(rcl3) }, 725 { IEEE80211_MODE_11A, X(rcl1) }, 726 { IEEE80211_MODE_11A, X(rcl2) }, 727 { IEEE80211_MODE_11B, X(rcl8) }, 728 { IEEE80211_MODE_11B, X(rcl9) }, 729 { IEEE80211_MODE_11A, X(rcl4) }, 730 #ifdef ATH_TURBO_SCAN 731 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 732 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 733 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 734 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 735 #endif /* ATH_TURBO_SCAN */ 736 { IEEE80211_MODE_11A, X(rcl7) }, 737 { IEEE80211_MODE_11B, X(rcl10) }, 738 { IEEE80211_MODE_11A, X(rcl11) }, 739 #ifdef ATH_TURBO_SCAN 740 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 741 #endif /* ATH_TURBO_SCAN */ 742 { .list = NULL } 743 }; 744 745 /* 746 * Start a station-mode scan by populating the channel list. 747 */ 748 static int 749 sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 750 { 751 struct sta_table *st = ss->ss_priv; 752 753 makescanlist(ss, vap, staScanTable); 754 755 if (ss->ss_mindwell == 0) 756 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 757 if (ss->ss_maxdwell == 0) 758 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 759 760 st->st_scangen++; 761 st->st_newscan = 1; 762 763 return 0; 764 } 765 766 /* 767 * Restart a scan, typically a bg scan but can 768 * also be a fg scan that came up empty. 769 */ 770 static int 771 sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 772 { 773 struct sta_table *st = ss->ss_priv; 774 775 st->st_newscan = 1; 776 return 0; 777 } 778 779 /* 780 * Cancel an ongoing scan. 781 */ 782 static int 783 sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 784 { 785 return 0; 786 } 787 788 /* 789 * Demote any supplied 11g channel to 11b. There should 790 * always be an 11b channel but we check anyway... 791 */ 792 static struct ieee80211_channel * 793 demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 794 { 795 struct ieee80211_channel *c; 796 797 if (IEEE80211_IS_CHAN_ANYG(chan) && 798 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 799 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 800 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 801 IEEE80211_CHAN_B); 802 if (c != NULL) 803 chan = c; 804 } 805 return chan; 806 } 807 808 static int 809 maxrate(const struct ieee80211_scan_entry *se) 810 { 811 const struct ieee80211_ie_htcap *htcap = 812 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 813 int rmax, r, i, txstream; 814 uint16_t caps; 815 uint8_t txparams; 816 817 rmax = 0; 818 if (htcap != NULL) { 819 /* 820 * HT station; inspect supported MCS and then adjust 821 * rate by channel width. 822 */ 823 txparams = htcap->hc_mcsset[12]; 824 if (txparams & 0x3) { 825 /* 826 * TX MCS parameters defined and not equal to RX, 827 * extract the number of spartial streams and 828 * map it to the highest MCS rate. 829 */ 830 txstream = ((txparams & 0xc) >> 2) + 1; 831 i = txstream * 8 - 1; 832 } else 833 for (i = 31; i >= 0 && isclr(htcap->hc_mcsset, i); i--); 834 if (i >= 0) { 835 caps = le16dec(&htcap->hc_cap); 836 if ((caps & IEEE80211_HTCAP_CHWIDTH40) && 837 (caps & IEEE80211_HTCAP_SHORTGI40)) 838 rmax = ieee80211_htrates[i].ht40_rate_400ns; 839 else if (caps & IEEE80211_HTCAP_CHWIDTH40) 840 rmax = ieee80211_htrates[i].ht40_rate_800ns; 841 else if (caps & IEEE80211_HTCAP_SHORTGI20) 842 rmax = ieee80211_htrates[i].ht20_rate_400ns; 843 else 844 rmax = ieee80211_htrates[i].ht20_rate_800ns; 845 } 846 } 847 for (i = 0; i < se->se_rates[1]; i++) { 848 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 849 if (r > rmax) 850 rmax = r; 851 } 852 for (i = 0; i < se->se_xrates[1]; i++) { 853 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 854 if (r > rmax) 855 rmax = r; 856 } 857 return rmax; 858 } 859 860 /* 861 * Compare the capabilities of two entries and decide which is 862 * more desirable (return >0 if a is considered better). Note 863 * that we assume compatibility/usability has already been checked 864 * so we don't need to (e.g. validate whether privacy is supported). 865 * Used to select the best scan candidate for association in a BSS. 866 * 867 * TODO: should we take 11n, 11ac into account when selecting the 868 * best? Right now it just compares frequency band and RSSI. 869 */ 870 static int 871 sta_compare(const struct sta_entry *a, const struct sta_entry *b) 872 { 873 #define PREFER(_a,_b,_what) do { \ 874 if (((_a) ^ (_b)) & (_what)) \ 875 return ((_a) & (_what)) ? 1 : -1; \ 876 } while (0) 877 int maxa, maxb; 878 int8_t rssia, rssib; 879 int weight; 880 881 /* privacy support */ 882 PREFER(a->base.se_capinfo, b->base.se_capinfo, 883 IEEE80211_CAPINFO_PRIVACY); 884 885 /* compare count of previous failures */ 886 weight = b->se_fails - a->se_fails; 887 if (abs(weight) > 1) 888 return weight; 889 890 /* 891 * Compare rssi. If the two are considered equivalent 892 * then fallback to other criteria. We threshold the 893 * comparisons to avoid selecting an ap purely by rssi 894 * when both values may be good but one ap is otherwise 895 * more desirable (e.g. an 11b-only ap with stronger 896 * signal than an 11g ap). 897 */ 898 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 899 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 900 if (abs(rssib - rssia) < 5) { 901 /* best/max rate preferred if signal level close enough XXX */ 902 maxa = maxrate(&a->base); 903 maxb = maxrate(&b->base); 904 if (maxa != maxb) 905 return maxa - maxb; 906 /* XXX use freq for channel preference */ 907 /* for now just prefer 5Ghz band to all other bands */ 908 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 909 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 910 } 911 /* all things being equal, use signal level */ 912 return a->base.se_rssi - b->base.se_rssi; 913 #undef PREFER 914 } 915 916 /* 917 * Check rate set suitability and return the best supported rate. 918 * XXX inspect MCS for HT 919 */ 920 static int 921 check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 922 const struct ieee80211_scan_entry *se) 923 { 924 const struct ieee80211_rateset *srs; 925 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 926 const uint8_t *rs; 927 928 okrate = badrate = 0; 929 930 srs = ieee80211_get_suprates(vap->iv_ic, chan); 931 nrs = se->se_rates[1]; 932 rs = se->se_rates+2; 933 /* XXX MCS */ 934 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 935 fixedrate = IEEE80211_FIXED_RATE_NONE; 936 again: 937 for (i = 0; i < nrs; i++) { 938 r = IEEE80211_RV(rs[i]); 939 badrate = r; 940 /* 941 * Check any fixed rate is included. 942 */ 943 if (r == ucastrate) 944 fixedrate = r; 945 /* 946 * Check against our supported rates. 947 */ 948 for (j = 0; j < srs->rs_nrates; j++) 949 if (r == IEEE80211_RV(srs->rs_rates[j])) { 950 if (r > okrate) /* NB: track max */ 951 okrate = r; 952 break; 953 } 954 955 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 956 /* 957 * Don't try joining a BSS, if we don't support 958 * one of its basic rates. 959 */ 960 okrate = 0; 961 goto back; 962 } 963 } 964 if (rs == se->se_rates+2) { 965 /* scan xrates too; sort of an algol68-style for loop */ 966 nrs = se->se_xrates[1]; 967 rs = se->se_xrates+2; 968 goto again; 969 } 970 971 back: 972 if (okrate == 0 || ucastrate != fixedrate) 973 return badrate | IEEE80211_RATE_BASIC; 974 else 975 return IEEE80211_RV(okrate); 976 } 977 978 static __inline int 979 match_id(const uint8_t *ie, const uint8_t *val, int len) 980 { 981 return (ie[1] == len && memcmp(ie+2, val, len) == 0); 982 } 983 984 static int 985 match_ssid(const uint8_t *ie, 986 int nssid, const struct ieee80211_scan_ssid ssids[]) 987 { 988 int i; 989 990 for (i = 0; i < nssid; i++) { 991 if (match_id(ie, ssids[i].ssid, ssids[i].len)) 992 return 1; 993 } 994 return 0; 995 } 996 997 #ifdef IEEE80211_SUPPORT_TDMA 998 static int 999 tdma_isfull(const struct ieee80211_tdma_param *tdma) 1000 { 1001 int slot, slotcnt; 1002 1003 slotcnt = tdma->tdma_slotcnt; 1004 for (slot = slotcnt-1; slot >= 0; slot--) 1005 if (isclr(tdma->tdma_inuse, slot)) 1006 return 0; 1007 return 1; 1008 } 1009 #endif /* IEEE80211_SUPPORT_TDMA */ 1010 1011 /* 1012 * Test a scan candidate for suitability/compatibility. 1013 */ 1014 static int 1015 match_bss(struct ieee80211vap *vap, 1016 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 1017 int debug) 1018 { 1019 struct ieee80211com *ic = vap->iv_ic; 1020 struct ieee80211_scan_entry *se = &se0->base; 1021 uint8_t rate; 1022 int fail; 1023 1024 fail = 0; 1025 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 1026 fail |= MATCH_CHANNEL; 1027 /* 1028 * NB: normally the desired mode is used to construct 1029 * the channel list, but it's possible for the scan 1030 * cache to include entries for stations outside this 1031 * list so we check the desired mode here to weed them 1032 * out. 1033 */ 1034 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 1035 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 1036 chanflags[vap->iv_des_mode]) 1037 fail |= MATCH_CHANNEL; 1038 if (vap->iv_opmode == IEEE80211_M_IBSS) { 1039 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 1040 fail |= MATCH_CAPINFO; 1041 #ifdef IEEE80211_SUPPORT_TDMA 1042 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { 1043 /* 1044 * Adhoc demo network setup shouldn't really be scanning 1045 * but just in case skip stations operating in IBSS or 1046 * BSS mode. 1047 */ 1048 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1049 fail |= MATCH_CAPINFO; 1050 /* 1051 * TDMA operation cannot coexist with a normal 802.11 network; 1052 * skip if IBSS or ESS capabilities are marked and require 1053 * the beacon have a TDMA ie present. 1054 */ 1055 if (vap->iv_caps & IEEE80211_C_TDMA) { 1056 const struct ieee80211_tdma_param *tdma = 1057 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; 1058 const struct ieee80211_tdma_state *ts = vap->iv_tdma; 1059 1060 if (tdma == NULL) 1061 fail |= MATCH_TDMA_NOIE; 1062 else if (tdma->tdma_version != ts->tdma_version) 1063 fail |= MATCH_TDMA_VERSION; 1064 else if (tdma->tdma_slot != 0) 1065 fail |= MATCH_TDMA_NOTMASTER; 1066 else if (tdma_isfull(tdma)) 1067 fail |= MATCH_TDMA_NOSLOT; 1068 #if 0 1069 else if (ieee80211_local_address(se->se_macaddr)) 1070 fail |= MATCH_TDMA_LOCAL; 1071 #endif 1072 } 1073 #endif /* IEEE80211_SUPPORT_TDMA */ 1074 #ifdef IEEE80211_SUPPORT_MESH 1075 } else if (vap->iv_opmode == IEEE80211_M_MBSS) { 1076 const struct ieee80211_mesh_state *ms = vap->iv_mesh; 1077 /* 1078 * Mesh nodes have IBSS & ESS bits in capinfo turned off 1079 * and two special ie's that must be present. 1080 */ 1081 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1082 fail |= MATCH_CAPINFO; 1083 else if (se->se_meshid[0] != IEEE80211_ELEMID_MESHID) 1084 fail |= MATCH_MESH_NOID; 1085 else if (ms->ms_idlen != 0 && 1086 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) 1087 fail |= MATCH_MESHID; 1088 #endif 1089 } else { 1090 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 1091 fail |= MATCH_CAPINFO; 1092 /* 1093 * If 11d is enabled and we're attempting to join a bss 1094 * that advertises it's country code then compare our 1095 * current settings to what we fetched from the country ie. 1096 * If our country code is unspecified or different then do 1097 * not attempt to join the bss. We should have already 1098 * dispatched an event to user space that identifies the 1099 * new country code so our regdomain config should match. 1100 */ 1101 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 1102 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 1103 se->se_cc[0] != 0 && 1104 (ic->ic_regdomain.country == CTRY_DEFAULT || 1105 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 1106 fail |= MATCH_CC; 1107 } 1108 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 1109 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 1110 fail |= MATCH_PRIVACY; 1111 } else { 1112 /* XXX does this mean privacy is supported or required? */ 1113 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 1114 fail |= MATCH_PRIVACY; 1115 } 1116 se0->se_flags &= ~STA_DEMOTE11B; 1117 rate = check_rate(vap, se->se_chan, se); 1118 if (rate & IEEE80211_RATE_BASIC) { 1119 fail |= MATCH_RATE; 1120 /* 1121 * An 11b-only ap will give a rate mismatch if there is an 1122 * OFDM fixed tx rate for 11g. Try downgrading the channel 1123 * in the scan list to 11b and retry the rate check. 1124 */ 1125 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 1126 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 1127 if ((rate & IEEE80211_RATE_BASIC) == 0) { 1128 fail &= ~MATCH_RATE; 1129 se0->se_flags |= STA_DEMOTE11B; 1130 } 1131 } 1132 } else if (rate < 2*24) { 1133 /* 1134 * This is an 11b-only ap. Check the desired mode in 1135 * case that needs to be honored (mode 11g filters out 1136 * 11b-only ap's). Otherwise force any 11g channel used 1137 * in scanning to be demoted. 1138 * 1139 * NB: we cheat a bit here by looking at the max rate; 1140 * we could/should check the rates. 1141 */ 1142 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 1143 vap->iv_des_mode == IEEE80211_MODE_11B)) 1144 fail |= MATCH_RATE; 1145 else 1146 se0->se_flags |= STA_DEMOTE11B; 1147 } 1148 if (ss->ss_nssid != 0 && 1149 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 1150 fail |= MATCH_SSID; 1151 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 1152 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 1153 fail |= MATCH_BSSID; 1154 if (se0->se_fails >= STA_FAILS_MAX) 1155 fail |= MATCH_FAILS; 1156 if (se0->se_notseen >= STA_PURGE_SCANS) 1157 fail |= MATCH_NOTSEEN; 1158 if (se->se_rssi < STA_RSSI_MIN) 1159 fail |= MATCH_RSSI; 1160 #ifdef IEEE80211_DEBUG 1161 if (ieee80211_msg(vap, debug)) { 1162 printf(" %c %s", 1163 fail & MATCH_FAILS ? '=' : 1164 fail & MATCH_NOTSEEN ? '^' : 1165 fail & MATCH_CC ? '$' : 1166 #ifdef IEEE80211_SUPPORT_TDMA 1167 fail & MATCH_TDMA_NOIE ? '&' : 1168 fail & MATCH_TDMA_VERSION ? 'v' : 1169 fail & MATCH_TDMA_NOTMASTER ? 's' : 1170 fail & MATCH_TDMA_NOSLOT ? 'f' : 1171 fail & MATCH_TDMA_LOCAL ? 'l' : 1172 #endif 1173 fail & MATCH_MESH_NOID ? 'm' : 1174 fail ? '-' : '+', ether_sprintf(se->se_macaddr)); 1175 printf(" %s%c", ether_sprintf(se->se_bssid), 1176 fail & MATCH_BSSID ? '!' : ' '); 1177 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 1178 fail & MATCH_CHANNEL ? '!' : ' '); 1179 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 1180 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 1181 fail & MATCH_RATE ? '!' : ' '); 1182 printf(" %4s%c", 1183 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 1184 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", 1185 fail & MATCH_CAPINFO ? '!' : ' '); 1186 printf(" %3s%c ", 1187 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 1188 "wep" : "no", 1189 fail & MATCH_PRIVACY ? '!' : ' '); 1190 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 1191 printf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); 1192 } 1193 #endif 1194 return fail; 1195 } 1196 1197 static void 1198 sta_update_notseen(struct sta_table *st) 1199 { 1200 struct sta_entry *se; 1201 1202 IEEE80211_SCAN_TABLE_LOCK(st); 1203 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1204 /* 1205 * If seen the reset and don't bump the count; 1206 * otherwise bump the ``not seen'' count. Note 1207 * that this insures that stations for which we 1208 * see frames while not scanning but not during 1209 * this scan will not be penalized. 1210 */ 1211 if (se->se_seen) 1212 se->se_seen = 0; 1213 else 1214 se->se_notseen++; 1215 } 1216 IEEE80211_SCAN_TABLE_UNLOCK(st); 1217 } 1218 1219 static void 1220 sta_dec_fails(struct sta_table *st) 1221 { 1222 struct sta_entry *se; 1223 1224 IEEE80211_SCAN_TABLE_LOCK(st); 1225 TAILQ_FOREACH(se, &st->st_entry, se_list) 1226 if (se->se_fails) 1227 se->se_fails--; 1228 IEEE80211_SCAN_TABLE_UNLOCK(st); 1229 } 1230 1231 static struct sta_entry * 1232 select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1233 { 1234 struct sta_table *st = ss->ss_priv; 1235 struct sta_entry *se, *selbs = NULL; 1236 1237 IEEE80211_DPRINTF(vap, debug, " %s\n", 1238 "macaddr bssid chan rssi rate flag wep essid"); 1239 IEEE80211_SCAN_TABLE_LOCK(st); 1240 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1241 ieee80211_ies_expand(&se->base.se_ies); 1242 if (match_bss(vap, ss, se, debug) == 0) { 1243 if (selbs == NULL) 1244 selbs = se; 1245 else if (sta_compare(se, selbs) > 0) 1246 selbs = se; 1247 } 1248 } 1249 IEEE80211_SCAN_TABLE_UNLOCK(st); 1250 1251 return selbs; 1252 } 1253 1254 /* 1255 * Pick an ap or ibss network to join or find a channel 1256 * to use to start an ibss network. 1257 */ 1258 static int 1259 sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1260 { 1261 struct sta_table *st = ss->ss_priv; 1262 struct sta_entry *selbs; 1263 struct ieee80211_channel *chan; 1264 1265 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1266 ("wrong mode %u", vap->iv_opmode)); 1267 1268 if (st->st_newscan) { 1269 sta_update_notseen(st); 1270 st->st_newscan = 0; 1271 } 1272 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1273 /* 1274 * Manual/background scan, don't select+join the 1275 * bss, just return. The scanning framework will 1276 * handle notification that this has completed. 1277 */ 1278 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1279 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1280 "%s: nopick; return 1\n", __func__); 1281 return 1; 1282 } 1283 /* 1284 * Automatic sequencing; look for a candidate and 1285 * if found join the network. 1286 */ 1287 /* NB: unlocked read should be ok */ 1288 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1289 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1290 "%s: no scan candidate, join=%d, return 0\n", 1291 __func__, 1292 !! (ss->ss_flags & IEEE80211_SCAN_NOJOIN)); 1293 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1294 return 0; 1295 notfound: 1296 /* 1297 * If nothing suitable was found decrement 1298 * the failure counts so entries will be 1299 * reconsidered the next time around. We 1300 * really want to do this only for sta's 1301 * where we've previously had some success. 1302 */ 1303 sta_dec_fails(st); 1304 st->st_newscan = 1; 1305 return 0; /* restart scan */ 1306 } 1307 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1308 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1309 return (selbs != NULL); 1310 if (selbs == NULL) 1311 goto notfound; 1312 chan = selbs->base.se_chan; 1313 if (selbs->se_flags & STA_DEMOTE11B) 1314 chan = demote11b(vap, chan); 1315 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1316 goto notfound; 1317 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1318 "%s: terminate scan; return 1\n", __func__); 1319 return 1; /* terminate scan */ 1320 } 1321 1322 /* 1323 * Lookup an entry in the scan cache. We assume we're 1324 * called from the bottom half or such that we don't need 1325 * to block the bottom half so that it's safe to return 1326 * a reference to an entry w/o holding the lock on the table. 1327 */ 1328 static struct sta_entry * 1329 sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1330 { 1331 struct sta_entry *se; 1332 int hash = STA_HASH(macaddr); 1333 1334 IEEE80211_SCAN_TABLE_LOCK(st); 1335 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1336 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1337 break; 1338 IEEE80211_SCAN_TABLE_UNLOCK(st); 1339 1340 return se; /* NB: unlocked */ 1341 } 1342 1343 static void 1344 sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1345 { 1346 struct ieee80211com *ic = vap->iv_ic; 1347 struct ieee80211_node *ni = vap->iv_bss; 1348 struct sta_table *st = ss->ss_priv; 1349 enum ieee80211_phymode mode; 1350 struct sta_entry *se, *selbs; 1351 uint8_t roamRate, curRate, ucastRate; 1352 int8_t roamRssi, curRssi; 1353 1354 se = sta_lookup(st, ni->ni_macaddr); 1355 if (se == NULL) { 1356 /* XXX something is wrong */ 1357 return; 1358 } 1359 1360 mode = ieee80211_chan2mode(ic->ic_bsschan); 1361 roamRate = vap->iv_roamparms[mode].rate; 1362 roamRssi = vap->iv_roamparms[mode].rssi; 1363 KASSERT(roamRate != 0 && roamRssi != 0, ("iv_roamparms are not" 1364 "initialized for %s mode!", ieee80211_phymode_name[mode])); 1365 1366 ucastRate = vap->iv_txparms[mode].ucastrate; 1367 /* NB: the most up to date rssi is in the node, not the scan cache */ 1368 curRssi = ic->ic_node_getrssi(ni); 1369 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1370 curRate = ni->ni_txrate; 1371 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1372 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1373 __func__, curRssi, curRate, roamRssi, roamRate); 1374 } else { 1375 curRate = roamRate; /* NB: insure compare below fails */ 1376 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1377 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1378 } 1379 /* 1380 * Check if a new ap should be used and switch. 1381 * XXX deauth current ap 1382 */ 1383 if (curRate < roamRate || curRssi < roamRssi) { 1384 if (ieee80211_time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1385 /* 1386 * Scan cache contents are too old; force a scan now 1387 * if possible so we have current state to make a 1388 * decision with. We don't kick off a bg scan if 1389 * we're using dynamic turbo and boosted or if the 1390 * channel is busy. 1391 * XXX force immediate switch on scan complete 1392 */ 1393 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1394 ((vap->iv_flags_ext & IEEE80211_FEXT_SCAN_OFFLOAD) || 1395 ieee80211_time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle))) 1396 ieee80211_bg_scan(vap, 0); 1397 return; 1398 } 1399 se->base.se_rssi = curRssi; 1400 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1401 if (selbs != NULL && selbs != se) { 1402 struct ieee80211_channel *chan; 1403 1404 IEEE80211_DPRINTF(vap, 1405 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1406 "%s: ROAM: curRate %u, roamRate %u, " 1407 "curRssi %d, roamRssi %d\n", __func__, 1408 curRate, roamRate, curRssi, roamRssi); 1409 1410 chan = selbs->base.se_chan; 1411 if (selbs->se_flags & STA_DEMOTE11B) 1412 chan = demote11b(vap, chan); 1413 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1414 } 1415 } 1416 } 1417 1418 /* 1419 * Age entries in the scan cache. 1420 * XXX also do roaming since it's convenient 1421 */ 1422 static void 1423 sta_age(struct ieee80211_scan_state *ss) 1424 { 1425 struct ieee80211vap *vap = ss->ss_vap; 1426 1427 adhoc_age(ss); 1428 /* 1429 * If rate control is enabled check periodically to see if 1430 * we should roam from our current connection to one that 1431 * might be better. This only applies when we're operating 1432 * in sta mode and automatic roaming is set. 1433 * XXX defer if busy 1434 * XXX repeater station 1435 * XXX do when !bgscan? 1436 */ 1437 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1438 ("wrong mode %u", vap->iv_opmode)); 1439 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1440 (vap->iv_flags & IEEE80211_F_BGSCAN) && 1441 vap->iv_state >= IEEE80211_S_RUN) 1442 /* XXX vap is implicit */ 1443 sta_roam_check(ss, vap); 1444 } 1445 1446 /* 1447 * Iterate over the entries in the scan cache, invoking 1448 * the callback function on each one. 1449 */ 1450 static void 1451 sta_iterate(struct ieee80211_scan_state *ss, 1452 ieee80211_scan_iter_func *f, void *arg) 1453 { 1454 struct sta_table *st = ss->ss_priv; 1455 struct sta_entry *se; 1456 u_int gen; 1457 1458 IEEE80211_SCAN_ITER_LOCK(st); 1459 gen = st->st_scaniter++; 1460 restart: 1461 IEEE80211_SCAN_TABLE_LOCK(st); 1462 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1463 if (se->se_scangen != gen) { 1464 se->se_scangen = gen; 1465 /* update public state */ 1466 se->base.se_age = ticks - se->se_lastupdate; 1467 IEEE80211_SCAN_TABLE_UNLOCK(st); 1468 (*f)(arg, &se->base); 1469 goto restart; 1470 } 1471 } 1472 IEEE80211_SCAN_TABLE_UNLOCK(st); 1473 1474 IEEE80211_SCAN_ITER_UNLOCK(st); 1475 } 1476 1477 static void 1478 sta_assoc_fail(struct ieee80211_scan_state *ss, 1479 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1480 { 1481 struct sta_table *st = ss->ss_priv; 1482 struct sta_entry *se; 1483 1484 se = sta_lookup(st, macaddr); 1485 if (se != NULL) { 1486 se->se_fails++; 1487 se->se_lastfail = ticks; 1488 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1489 macaddr, "%s: reason %u fails %u", 1490 __func__, reason, se->se_fails); 1491 } 1492 } 1493 1494 static void 1495 sta_assoc_success(struct ieee80211_scan_state *ss, 1496 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1497 { 1498 struct sta_table *st = ss->ss_priv; 1499 struct sta_entry *se; 1500 1501 se = sta_lookup(st, macaddr); 1502 if (se != NULL) { 1503 #if 0 1504 se->se_fails = 0; 1505 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1506 macaddr, "%s: fails %u", 1507 __func__, se->se_fails); 1508 #endif 1509 se->se_lastassoc = ticks; 1510 } 1511 } 1512 1513 static const struct ieee80211_scanner sta_default = { 1514 .scan_name = "default", 1515 .scan_attach = sta_attach, 1516 .scan_detach = sta_detach, 1517 .scan_start = sta_start, 1518 .scan_restart = sta_restart, 1519 .scan_cancel = sta_cancel, 1520 .scan_end = sta_pick_bss, 1521 .scan_flush = sta_flush, 1522 .scan_add = sta_add, 1523 .scan_age = sta_age, 1524 .scan_iterate = sta_iterate, 1525 .scan_assoc_fail = sta_assoc_fail, 1526 .scan_assoc_success = sta_assoc_success, 1527 }; 1528 IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); 1529 1530 /* 1531 * Adhoc mode-specific support. 1532 */ 1533 1534 static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1535 { 5180, 5200, 5220, 5240 }; 1536 static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1537 { 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1538 static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1539 { 5170, 5190, 5210, 5230 }; 1540 static const uint16_t adhoc11b[] = /* 10, 11 */ 1541 { 2457, 2462 }; 1542 1543 static const struct scanlist adhocScanTable[] = { 1544 { IEEE80211_MODE_11B, X(adhoc11b) }, 1545 { IEEE80211_MODE_11A, X(adhocWorld) }, 1546 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1547 { IEEE80211_MODE_11B, X(adhocMkk) }, 1548 { .list = NULL } 1549 }; 1550 #undef X 1551 1552 /* 1553 * Start an adhoc-mode scan by populating the channel list. 1554 */ 1555 static int 1556 adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1557 { 1558 struct sta_table *st = ss->ss_priv; 1559 1560 makescanlist(ss, vap, adhocScanTable); 1561 1562 if (ss->ss_mindwell == 0) 1563 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1564 if (ss->ss_maxdwell == 0) 1565 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1566 1567 st->st_scangen++; 1568 st->st_newscan = 1; 1569 1570 return 0; 1571 } 1572 1573 /* 1574 * Select a channel to start an adhoc network on. 1575 * The channel list was populated with appropriate 1576 * channels so select one that looks least occupied. 1577 */ 1578 static struct ieee80211_channel * 1579 adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1580 { 1581 struct sta_table *st = ss->ss_priv; 1582 struct sta_entry *se; 1583 struct ieee80211_channel *c, *bestchan; 1584 int i, bestrssi, maxrssi; 1585 1586 bestchan = NULL; 1587 bestrssi = -1; 1588 1589 IEEE80211_SCAN_TABLE_LOCK(st); 1590 for (i = 0; i < ss->ss_last; i++) { 1591 c = ss->ss_chans[i]; 1592 /* never consider a channel with radar */ 1593 if (IEEE80211_IS_CHAN_RADAR(c)) 1594 continue; 1595 /* skip channels disallowed by regulatory settings */ 1596 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1597 continue; 1598 /* check channel attributes for band compatibility */ 1599 if (flags != 0 && (c->ic_flags & flags) != flags) 1600 continue; 1601 maxrssi = 0; 1602 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1603 if (se->base.se_chan != c) 1604 continue; 1605 if (se->base.se_rssi > maxrssi) 1606 maxrssi = se->base.se_rssi; 1607 } 1608 if (bestchan == NULL || maxrssi < bestrssi) 1609 bestchan = c; 1610 } 1611 IEEE80211_SCAN_TABLE_UNLOCK(st); 1612 1613 return bestchan; 1614 } 1615 1616 /* 1617 * Pick an ibss network to join or find a channel 1618 * to use to start an ibss network. 1619 */ 1620 static int 1621 adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1622 { 1623 struct sta_table *st = ss->ss_priv; 1624 struct sta_entry *selbs; 1625 struct ieee80211_channel *chan; 1626 struct ieee80211com *ic = vap->iv_ic; 1627 1628 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1629 vap->iv_opmode == IEEE80211_M_AHDEMO || 1630 vap->iv_opmode == IEEE80211_M_MBSS, 1631 ("wrong opmode %u", vap->iv_opmode)); 1632 1633 if (st->st_newscan) { 1634 sta_update_notseen(st); 1635 st->st_newscan = 0; 1636 } 1637 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1638 /* 1639 * Manual/background scan, don't select+join the 1640 * bss, just return. The scanning framework will 1641 * handle notification that this has completed. 1642 */ 1643 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1644 return 1; 1645 } 1646 /* 1647 * Automatic sequencing; look for a candidate and 1648 * if found join the network. 1649 */ 1650 /* NB: unlocked read should be ok */ 1651 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1652 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1653 "%s: no scan candidate\n", __func__); 1654 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1655 return 0; 1656 notfound: 1657 /* NB: never auto-start a tdma network for slot !0 */ 1658 #ifdef IEEE80211_SUPPORT_TDMA 1659 if (vap->iv_des_nssid && 1660 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || 1661 ieee80211_tdma_getslot(vap) == 0)) { 1662 #else 1663 if (vap->iv_des_nssid) { 1664 #endif 1665 /* 1666 * No existing adhoc network to join and we have 1667 * an ssid; start one up. If no channel was 1668 * specified, try to select a channel. 1669 */ 1670 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1671 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1672 chan = adhoc_pick_channel(ss, 0); 1673 } else 1674 chan = vap->iv_des_chan; 1675 if (chan != NULL) { 1676 /* 1677 * Create a HT capable IBSS; the per-node 1678 * probe request/response will result in 1679 * "correct" rate control capabilities being 1680 * negotiated. 1681 */ 1682 chan = ieee80211_ht_adjust_channel(ic, 1683 chan, vap->iv_flags_ht); 1684 chan = ieee80211_vht_adjust_channel(ic, 1685 chan, vap->iv_flags_vht); 1686 ieee80211_create_ibss(vap, chan); 1687 return 1; 1688 } 1689 } 1690 /* 1691 * If nothing suitable was found decrement 1692 * the failure counts so entries will be 1693 * reconsidered the next time around. We 1694 * really want to do this only for sta's 1695 * where we've previously had some success. 1696 */ 1697 sta_dec_fails(st); 1698 st->st_newscan = 1; 1699 return 0; /* restart scan */ 1700 } 1701 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1702 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1703 return (selbs != NULL); 1704 if (selbs == NULL) 1705 goto notfound; 1706 chan = selbs->base.se_chan; 1707 if (selbs->se_flags & STA_DEMOTE11B) 1708 chan = demote11b(vap, chan); 1709 /* 1710 * If HT is available, make it a possibility here. 1711 * The intent is to enable HT20/HT40 when joining a non-HT 1712 * IBSS node; we can then advertise HT IEs and speak HT 1713 * to any subsequent nodes that support it. 1714 */ 1715 chan = ieee80211_ht_adjust_channel(ic, 1716 chan, vap->iv_flags_ht); 1717 chan = ieee80211_vht_adjust_channel(ic, 1718 chan, vap->iv_flags_vht); 1719 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1720 goto notfound; 1721 return 1; /* terminate scan */ 1722 } 1723 1724 /* 1725 * Age entries in the scan cache. 1726 */ 1727 static void 1728 adhoc_age(struct ieee80211_scan_state *ss) 1729 { 1730 struct sta_table *st = ss->ss_priv; 1731 struct sta_entry *se, *next; 1732 1733 IEEE80211_SCAN_TABLE_LOCK(st); 1734 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 1735 if (se->se_notseen > STA_PURGE_SCANS) { 1736 TAILQ_REMOVE(&st->st_entry, se, se_list); 1737 LIST_REMOVE(se, se_hash); 1738 ieee80211_ies_cleanup(&se->base.se_ies); 1739 IEEE80211_FREE(se, M_80211_SCAN); 1740 } 1741 } 1742 IEEE80211_SCAN_TABLE_UNLOCK(st); 1743 } 1744 1745 static const struct ieee80211_scanner adhoc_default = { 1746 .scan_name = "default", 1747 .scan_attach = sta_attach, 1748 .scan_detach = sta_detach, 1749 .scan_start = adhoc_start, 1750 .scan_restart = sta_restart, 1751 .scan_cancel = sta_cancel, 1752 .scan_end = adhoc_pick_bss, 1753 .scan_flush = sta_flush, 1754 .scan_pickchan = adhoc_pick_channel, 1755 .scan_add = sta_add, 1756 .scan_age = adhoc_age, 1757 .scan_iterate = sta_iterate, 1758 .scan_assoc_fail = sta_assoc_fail, 1759 .scan_assoc_success = sta_assoc_success, 1760 }; 1761 IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1762 IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1763 1764 static int 1765 ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1766 { 1767 struct sta_table *st = ss->ss_priv; 1768 1769 makescanlist(ss, vap, staScanTable); 1770 1771 if (ss->ss_mindwell == 0) 1772 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1773 if (ss->ss_maxdwell == 0) 1774 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1775 1776 st->st_scangen++; 1777 st->st_newscan = 1; 1778 1779 return 0; 1780 } 1781 1782 /* 1783 * Cancel an ongoing scan. 1784 */ 1785 static int 1786 ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1787 { 1788 return 0; 1789 } 1790 1791 /* 1792 * Pick a quiet channel to use for ap operation. 1793 */ 1794 static struct ieee80211_channel * 1795 ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1796 { 1797 struct sta_table *st = ss->ss_priv; 1798 struct ieee80211_channel *bestchan = NULL; 1799 int i; 1800 1801 /* XXX select channel more intelligently, e.g. channel spread, power */ 1802 /* NB: use scan list order to preserve channel preference */ 1803 for (i = 0; i < ss->ss_last; i++) { 1804 struct ieee80211_channel *chan = ss->ss_chans[i]; 1805 /* 1806 * If the channel is unoccupied the max rssi 1807 * should be zero; just take it. Otherwise 1808 * track the channel with the lowest rssi and 1809 * use that when all channels appear occupied. 1810 */ 1811 if (IEEE80211_IS_CHAN_RADAR(chan)) 1812 continue; 1813 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1814 continue; 1815 /* check channel attributes for band compatibility */ 1816 if (flags != 0 && (chan->ic_flags & flags) != flags) 1817 continue; 1818 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); 1819 /* XXX channel have interference */ 1820 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1821 /* XXX use other considerations */ 1822 return chan; 1823 } 1824 if (bestchan == NULL || 1825 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1826 bestchan = chan; 1827 } 1828 return bestchan; 1829 } 1830 1831 /* 1832 * Pick a quiet channel to use for ap operation. 1833 */ 1834 static int 1835 ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1836 { 1837 struct ieee80211com *ic = vap->iv_ic; 1838 struct ieee80211_channel *bestchan, *chan; 1839 1840 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1841 ("wrong opmode %u", vap->iv_opmode)); 1842 bestchan = ap_pick_channel(ss, 0); 1843 if (bestchan == NULL) { 1844 /* no suitable channel, should not happen */ 1845 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1846 "%s: no suitable channel! (should not happen)\n", __func__); 1847 /* XXX print something? */ 1848 return 0; /* restart scan */ 1849 } 1850 /* 1851 * If this is a dynamic turbo channel, start with the unboosted one. 1852 */ 1853 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1854 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1855 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1856 if (bestchan == NULL) { 1857 /* should never happen ?? */ 1858 return 0; 1859 } 1860 } 1861 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1862 /* 1863 * Manual/background scan, don't select+join the 1864 * bss, just return. The scanning framework will 1865 * handle notification that this has completed. 1866 */ 1867 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1868 return 1; 1869 } 1870 chan = ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht); 1871 chan = ieee80211_vht_adjust_channel(ic, chan, vap->iv_flags_vht); 1872 ieee80211_create_ibss(vap, chan); 1873 1874 return 1; 1875 } 1876 1877 static const struct ieee80211_scanner ap_default = { 1878 .scan_name = "default", 1879 .scan_attach = sta_attach, 1880 .scan_detach = sta_detach, 1881 .scan_start = ap_start, 1882 .scan_restart = sta_restart, 1883 .scan_cancel = ap_cancel, 1884 .scan_end = ap_end, 1885 .scan_flush = sta_flush, 1886 .scan_pickchan = ap_pick_channel, 1887 .scan_add = sta_add, 1888 .scan_age = adhoc_age, 1889 .scan_iterate = sta_iterate, 1890 .scan_assoc_success = sta_assoc_success, 1891 .scan_assoc_fail = sta_assoc_fail, 1892 }; 1893 IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1894 1895 #ifdef IEEE80211_SUPPORT_MESH 1896 /* 1897 * Pick an mbss network to join or find a channel 1898 * to use to start an mbss network. 1899 */ 1900 static int 1901 mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1902 { 1903 struct sta_table *st = ss->ss_priv; 1904 struct ieee80211_mesh_state *ms = vap->iv_mesh; 1905 struct sta_entry *selbs; 1906 struct ieee80211_channel *chan; 1907 1908 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, 1909 ("wrong opmode %u", vap->iv_opmode)); 1910 1911 if (st->st_newscan) { 1912 sta_update_notseen(st); 1913 st->st_newscan = 0; 1914 } 1915 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1916 /* 1917 * Manual/background scan, don't select+join the 1918 * bss, just return. The scanning framework will 1919 * handle notification that this has completed. 1920 */ 1921 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1922 return 1; 1923 } 1924 /* 1925 * Automatic sequencing; look for a candidate and 1926 * if found join the network. 1927 */ 1928 /* NB: unlocked read should be ok */ 1929 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1930 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1931 "%s: no scan candidate\n", __func__); 1932 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1933 return 0; 1934 notfound: 1935 if (ms->ms_idlen != 0) { 1936 /* 1937 * No existing mbss network to join and we have 1938 * a meshid; start one up. If no channel was 1939 * specified, try to select a channel. 1940 */ 1941 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1942 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1943 struct ieee80211com *ic = vap->iv_ic; 1944 1945 /* XXX VHT */ 1946 chan = adhoc_pick_channel(ss, 0); 1947 if (chan != NULL) { 1948 chan = ieee80211_ht_adjust_channel(ic, 1949 chan, vap->iv_flags_ht); 1950 chan = ieee80211_vht_adjust_channel(ic, 1951 chan, vap->iv_flags_vht); 1952 } 1953 } else 1954 chan = vap->iv_des_chan; 1955 if (chan != NULL) { 1956 ieee80211_create_ibss(vap, chan); 1957 return 1; 1958 } 1959 } 1960 /* 1961 * If nothing suitable was found decrement 1962 * the failure counts so entries will be 1963 * reconsidered the next time around. We 1964 * really want to do this only for sta's 1965 * where we've previously had some success. 1966 */ 1967 sta_dec_fails(st); 1968 st->st_newscan = 1; 1969 return 0; /* restart scan */ 1970 } 1971 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1972 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1973 return (selbs != NULL); 1974 if (selbs == NULL) 1975 goto notfound; 1976 chan = selbs->base.se_chan; 1977 if (selbs->se_flags & STA_DEMOTE11B) 1978 chan = demote11b(vap, chan); 1979 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1980 goto notfound; 1981 return 1; /* terminate scan */ 1982 } 1983 1984 static const struct ieee80211_scanner mesh_default = { 1985 .scan_name = "default", 1986 .scan_attach = sta_attach, 1987 .scan_detach = sta_detach, 1988 .scan_start = adhoc_start, 1989 .scan_restart = sta_restart, 1990 .scan_cancel = sta_cancel, 1991 .scan_end = mesh_pick_bss, 1992 .scan_flush = sta_flush, 1993 .scan_pickchan = adhoc_pick_channel, 1994 .scan_add = sta_add, 1995 .scan_age = adhoc_age, 1996 .scan_iterate = sta_iterate, 1997 .scan_assoc_fail = sta_assoc_fail, 1998 .scan_assoc_success = sta_assoc_success, 1999 }; 2000 IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); 2001 #endif /* IEEE80211_SUPPORT_MESH */ 2002