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