1 /*- 2 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include <sys/cdefs.h> 27 __FBSDID("$FreeBSD$"); 28 29 /* 30 * IEEE 802.11 station scanning support. 31 */ 32 #include "opt_wlan.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 #include <sys/module.h> 38 39 #include <sys/socket.h> 40 41 #include <net/if.h> 42 #include <net/if_media.h> 43 #include <net/ethernet.h> 44 45 #include <net80211/ieee80211_var.h> 46 #include <net80211/ieee80211_input.h> 47 #include <net80211/ieee80211_regdomain.h> 48 #ifdef IEEE80211_SUPPORT_TDMA 49 #include <net80211/ieee80211_tdma.h> 50 #endif 51 #ifdef IEEE80211_SUPPORT_MESH 52 #include <net80211/ieee80211_mesh.h> 53 #endif 54 55 #include <net/bpf.h> 56 57 /* 58 * Parameters for managing cache entries: 59 * 60 * o a station with STA_FAILS_MAX failures is not considered 61 * when picking a candidate 62 * o a station that hasn't had an update in STA_PURGE_SCANS 63 * (background) scans is discarded 64 * o after STA_FAILS_AGE seconds we clear the failure count 65 */ 66 #define STA_FAILS_MAX 2 /* assoc failures before ignored */ 67 #define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ 68 #define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ 69 70 /* XXX tunable */ 71 #define STA_RSSI_MIN 8 /* min acceptable rssi */ 72 #define STA_RSSI_MAX 40 /* max rssi for comparison */ 73 74 struct sta_entry { 75 struct ieee80211_scan_entry base; 76 TAILQ_ENTRY(sta_entry) se_list; 77 LIST_ENTRY(sta_entry) se_hash; 78 uint8_t se_fails; /* failure to associate count */ 79 uint8_t se_seen; /* seen during current scan */ 80 uint8_t se_notseen; /* not seen in previous scans */ 81 uint8_t se_flags; 82 #define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ 83 uint32_t se_avgrssi; /* LPF rssi state */ 84 unsigned long se_lastupdate; /* time of last update */ 85 unsigned long se_lastfail; /* time of last failure */ 86 unsigned long se_lastassoc; /* time of last association */ 87 u_int se_scangen; /* iterator scan gen# */ 88 u_int se_countrygen; /* gen# of last cc notify */ 89 }; 90 91 #define STA_HASHSIZE 32 92 /* simple hash is enough for variation of macaddr */ 93 #define STA_HASH(addr) \ 94 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) 95 96 #define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */ 97 CTASSERT(MAX_IEEE_CHAN >= 256); 98 99 struct sta_table { 100 ieee80211_scan_table_lock_t st_lock; /* on scan table */ 101 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 102 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 103 struct mtx st_scanlock; /* on st_scaniter */ 104 u_int st_scaniter; /* gen# for iterator */ 105 u_int st_scangen; /* scan generation # */ 106 int st_newscan; 107 /* ap-related state */ 108 int st_maxrssi[MAX_IEEE_CHAN]; 109 }; 110 111 static void sta_flush_table(struct sta_table *); 112 /* 113 * match_bss returns a bitmask describing if an entry is suitable 114 * for use. If non-zero the entry was deemed not suitable and it's 115 * contents explains why. The following flags are or'd to to this 116 * mask and can be used to figure out why the entry was rejected. 117 */ 118 #define MATCH_CHANNEL 0x00001 /* channel mismatch */ 119 #define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ 120 #define MATCH_PRIVACY 0x00004 /* privacy mismatch */ 121 #define MATCH_RATE 0x00008 /* rate set mismatch */ 122 #define MATCH_SSID 0x00010 /* ssid mismatch */ 123 #define MATCH_BSSID 0x00020 /* bssid mismatch */ 124 #define MATCH_FAILS 0x00040 /* too many failed auth attempts */ 125 #define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ 126 #define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ 127 #define MATCH_CC 0x00200 /* country code mismatch */ 128 #define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ 129 #define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ 130 #define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ 131 #define MATCH_TDMA_LOCAL 0x02000 /* local address */ 132 #define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ 133 #define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ 134 #define MATCH_MESHID 0x20000 /* meshid mismatch */ 135 static int match_bss(struct ieee80211vap *, 136 const struct ieee80211_scan_state *, struct sta_entry *, int); 137 static void adhoc_age(struct ieee80211_scan_state *); 138 139 static __inline int 140 isocmp(const uint8_t cc1[], const uint8_t cc2[]) 141 { 142 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 143 } 144 145 /* number of references from net80211 layer */ 146 static int nrefs = 0; 147 /* 148 * Module glue. 149 */ 150 IEEE80211_SCANNER_MODULE(sta, 1); 151 152 /* 153 * Attach prior to any scanning work. 154 */ 155 static int 156 sta_attach(struct ieee80211_scan_state *ss) 157 { 158 struct sta_table *st; 159 160 st = (struct sta_table *) malloc(sizeof(struct sta_table), 161 M_80211_SCAN, M_NOWAIT | M_ZERO); 162 if (st == NULL) 163 return 0; 164 IEEE80211_SCAN_TABLE_LOCK_INIT(st, "scantable"); 165 mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF); 166 TAILQ_INIT(&st->st_entry); 167 ss->ss_priv = st; 168 nrefs++; /* NB: we assume caller locking */ 169 return 1; 170 } 171 172 /* 173 * Cleanup any private state. 174 */ 175 static int 176 sta_detach(struct ieee80211_scan_state *ss) 177 { 178 struct sta_table *st = ss->ss_priv; 179 180 if (st != NULL) { 181 sta_flush_table(st); 182 IEEE80211_SCAN_TABLE_LOCK_DESTROY(st); 183 mtx_destroy(&st->st_scanlock); 184 free(st, M_80211_SCAN); 185 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 186 nrefs--; /* NB: we assume caller locking */ 187 } 188 return 1; 189 } 190 191 /* 192 * Flush all per-scan state. 193 */ 194 static int 195 sta_flush(struct ieee80211_scan_state *ss) 196 { 197 struct sta_table *st = ss->ss_priv; 198 199 IEEE80211_SCAN_TABLE_LOCK(st); 200 sta_flush_table(st); 201 IEEE80211_SCAN_TABLE_UNLOCK(st); 202 ss->ss_last = 0; 203 return 0; 204 } 205 206 /* 207 * Flush all entries in the scan cache. 208 */ 209 static void 210 sta_flush_table(struct sta_table *st) 211 { 212 struct sta_entry *se, *next; 213 214 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 215 TAILQ_REMOVE(&st->st_entry, se, se_list); 216 LIST_REMOVE(se, se_hash); 217 ieee80211_ies_cleanup(&se->base.se_ies); 218 free(se, M_80211_SCAN); 219 } 220 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 221 } 222 223 /* 224 * Process a beacon or probe response frame; create an 225 * entry in the scan cache or update any previous entry. 226 */ 227 static int 228 sta_add(struct ieee80211_scan_state *ss, 229 const struct ieee80211_scanparams *sp, 230 const struct ieee80211_frame *wh, 231 int subtype, int rssi, int noise) 232 { 233 #define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 234 #define PICK1ST(_ss) \ 235 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 236 IEEE80211_SCAN_PICK1ST) 237 struct sta_table *st = ss->ss_priv; 238 const uint8_t *macaddr = wh->i_addr2; 239 struct ieee80211vap *vap = ss->ss_vap; 240 struct ieee80211com *ic = vap->iv_ic; 241 struct ieee80211_channel *c; 242 struct sta_entry *se; 243 struct ieee80211_scan_entry *ise; 244 int hash; 245 246 hash = STA_HASH(macaddr); 247 248 IEEE80211_SCAN_TABLE_LOCK(st); 249 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 250 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 251 goto found; 252 se = (struct sta_entry *) malloc(sizeof(struct sta_entry), 253 M_80211_SCAN, M_NOWAIT | M_ZERO); 254 if (se == NULL) { 255 IEEE80211_SCAN_TABLE_UNLOCK(st); 256 return 0; 257 } 258 se->se_scangen = st->st_scaniter-1; 259 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 260 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 261 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 262 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 263 found: 264 ise = &se->base; 265 /* XXX ap beaconing multiple ssid w/ same bssid */ 266 if (sp->ssid[1] != 0 && 267 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 268 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 269 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 270 ("rate set too large: %u", sp->rates[1])); 271 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 272 if (sp->xrates != NULL) { 273 /* XXX validate xrates[1] */ 274 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 275 ("xrate set too large: %u", sp->xrates[1])); 276 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 277 } else 278 ise->se_xrates[1] = 0; 279 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 280 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 281 /* 282 * Record rssi data using extended precision LPF filter. 283 * 284 * NB: use only on-channel data to insure we get a good 285 * estimate of the signal we'll see when associated. 286 */ 287 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 288 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 289 ise->se_noise = noise; 290 } 291 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 292 ise->se_intval = sp->bintval; 293 ise->se_capinfo = sp->capinfo; 294 #ifdef IEEE80211_SUPPORT_MESH 295 if (sp->meshid != NULL && sp->meshid[1] != 0) 296 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); 297 #endif 298 /* 299 * Beware of overriding se_chan for frames seen 300 * off-channel; this can cause us to attempt an 301 * association on the wrong channel. 302 */ 303 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 304 /* 305 * Off-channel, locate the home/bss channel for the sta 306 * using the value broadcast in the DSPARMS ie. We know 307 * sp->chan has this value because it's used to calculate 308 * IEEE80211_BPARSE_OFFCHAN. 309 */ 310 c = ieee80211_find_channel_byieee(ic, sp->chan, 311 ic->ic_curchan->ic_flags); 312 if (c != NULL) { 313 ise->se_chan = c; 314 } else if (ise->se_chan == NULL) { 315 /* should not happen, pick something */ 316 ise->se_chan = ic->ic_curchan; 317 } 318 } else 319 ise->se_chan = ic->ic_curchan; 320 if (IEEE80211_IS_CHAN_HT(ise->se_chan) && sp->htcap == NULL) { 321 /* Demote legacy networks to a non-HT channel. */ 322 c = ieee80211_find_channel(ic, ise->se_chan->ic_freq, 323 ise->se_chan->ic_flags & ~IEEE80211_CHAN_HT); 324 KASSERT(c != NULL, 325 ("no legacy channel %u", ise->se_chan->ic_ieee)); 326 ise->se_chan = c; 327 } 328 ise->se_fhdwell = sp->fhdwell; 329 ise->se_fhindex = sp->fhindex; 330 ise->se_erp = sp->erp; 331 ise->se_timoff = sp->timoff; 332 if (sp->tim != NULL) { 333 const struct ieee80211_tim_ie *tim = 334 (const struct ieee80211_tim_ie *) sp->tim; 335 ise->se_dtimperiod = tim->tim_period; 336 } 337 if (sp->country != NULL) { 338 const struct ieee80211_country_ie *cie = 339 (const struct ieee80211_country_ie *) sp->country; 340 /* 341 * If 11d is enabled and we're attempting to join a bss 342 * that advertises it's country code then compare our 343 * current settings to what we fetched from the country ie. 344 * If our country code is unspecified or different then 345 * dispatch an event to user space that identifies the 346 * country code so our regdomain config can be changed. 347 */ 348 /* XXX only for STA mode? */ 349 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 350 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 351 (ic->ic_regdomain.country == CTRY_DEFAULT || 352 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 353 /* only issue one notify event per scan */ 354 if (se->se_countrygen != st->st_scangen) { 355 ieee80211_notify_country(vap, ise->se_bssid, 356 cie->cc); 357 se->se_countrygen = st->st_scangen; 358 } 359 } 360 ise->se_cc[0] = cie->cc[0]; 361 ise->se_cc[1] = cie->cc[1]; 362 } 363 /* NB: no need to setup ie ptrs; they are not (currently) used */ 364 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 365 366 /* clear failure count after STA_FAIL_AGE passes */ 367 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 368 se->se_fails = 0; 369 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 370 "%s: fails %u", __func__, se->se_fails); 371 } 372 373 se->se_lastupdate = ticks; /* update time */ 374 se->se_seen = 1; 375 se->se_notseen = 0; 376 377 KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); 378 if (rssi > st->st_maxrssi[sp->bchan]) 379 st->st_maxrssi[sp->bchan] = rssi; 380 381 IEEE80211_SCAN_TABLE_UNLOCK(st); 382 383 /* 384 * If looking for a quick choice and nothing's 385 * been found check here. 386 */ 387 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 388 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 389 390 return 1; 391 #undef PICK1ST 392 #undef ISPROBE 393 } 394 395 /* 396 * Check if a channel is excluded by user request. 397 */ 398 static int 399 isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 400 { 401 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 402 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 403 c->ic_freq != vap->iv_des_chan->ic_freq)); 404 } 405 406 static struct ieee80211_channel * 407 find11gchannel(struct ieee80211com *ic, int i, int freq) 408 { 409 struct ieee80211_channel *c; 410 int j; 411 412 /* 413 * The normal ordering in the channel list is b channel 414 * immediately followed by g so optimize the search for 415 * this. We'll still do a full search just in case. 416 */ 417 for (j = i+1; j < ic->ic_nchans; j++) { 418 c = &ic->ic_channels[j]; 419 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 420 return c; 421 } 422 for (j = 0; j < i; j++) { 423 c = &ic->ic_channels[j]; 424 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 425 return c; 426 } 427 return NULL; 428 } 429 430 static const u_int chanflags[IEEE80211_MODE_MAX] = { 431 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, 432 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, 433 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, 434 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, 435 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, 436 /* check base channel */ 437 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, 438 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, 439 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, 440 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, 441 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, 442 /* check legacy */ 443 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, 444 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, 445 }; 446 447 static void 448 add_channels(struct ieee80211vap *vap, 449 struct ieee80211_scan_state *ss, 450 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 451 { 452 #define N(a) (sizeof(a) / sizeof(a[0])) 453 struct ieee80211com *ic = vap->iv_ic; 454 struct ieee80211_channel *c, *cg; 455 u_int modeflags; 456 int i; 457 458 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode)); 459 modeflags = chanflags[mode]; 460 for (i = 0; i < nfreq; i++) { 461 if (ss->ss_last >= IEEE80211_SCAN_MAX) 462 break; 463 464 c = ieee80211_find_channel(ic, freq[i], modeflags); 465 if (c == NULL || isexcluded(vap, c)) 466 continue; 467 if (mode == IEEE80211_MODE_AUTO) { 468 /* 469 * XXX special-case 11b/g channels so we select 470 * the g channel if both are present. 471 */ 472 if (IEEE80211_IS_CHAN_B(c) && 473 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 474 c = cg; 475 } 476 ss->ss_chans[ss->ss_last++] = c; 477 } 478 #undef N 479 } 480 481 struct scanlist { 482 uint16_t mode; 483 uint16_t count; 484 const uint16_t *list; 485 }; 486 487 static int 488 checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 489 { 490 int i; 491 492 for (; scan->list != NULL; scan++) { 493 for (i = 0; i < scan->count; i++) 494 if (scan->list[i] == c->ic_freq) 495 return 1; 496 } 497 return 0; 498 } 499 500 static int 501 onscanlist(const struct ieee80211_scan_state *ss, 502 const struct ieee80211_channel *c) 503 { 504 int i; 505 506 for (i = 0; i < ss->ss_last; i++) 507 if (ss->ss_chans[i] == c) 508 return 1; 509 return 0; 510 } 511 512 static void 513 sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 514 const struct scanlist table[]) 515 { 516 struct ieee80211com *ic = vap->iv_ic; 517 struct ieee80211_channel *c; 518 int i; 519 520 for (i = 0; i < ic->ic_nchans; i++) { 521 if (ss->ss_last >= IEEE80211_SCAN_MAX) 522 break; 523 524 c = &ic->ic_channels[i]; 525 /* 526 * Ignore dynamic turbo channels; we scan them 527 * in normal mode (i.e. not boosted). Likewise 528 * for HT channels, they get scanned using 529 * legacy rates. 530 */ 531 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) 532 continue; 533 534 /* 535 * If a desired mode was specified, scan only 536 * channels that satisfy that constraint. 537 */ 538 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 539 vap->iv_des_mode != ieee80211_chan2mode(c)) 540 continue; 541 542 /* 543 * Skip channels excluded by user request. 544 */ 545 if (isexcluded(vap, c)) 546 continue; 547 548 /* 549 * Add the channel unless it is listed in the 550 * fixed scan order tables. This insures we 551 * don't sweep back in channels we filtered out 552 * above. 553 */ 554 if (checktable(table, c)) 555 continue; 556 557 /* Add channel to scanning list. */ 558 ss->ss_chans[ss->ss_last++] = c; 559 } 560 /* 561 * Explicitly add any desired channel if: 562 * - not already on the scan list 563 * - allowed by any desired mode constraint 564 * - there is space in the scan list 565 * This allows the channel to be used when the filtering 566 * mechanisms would otherwise elide it (e.g HT, turbo). 567 */ 568 c = vap->iv_des_chan; 569 if (c != IEEE80211_CHAN_ANYC && 570 !onscanlist(ss, c) && 571 (vap->iv_des_mode == IEEE80211_MODE_AUTO || 572 vap->iv_des_mode == ieee80211_chan2mode(c)) && 573 ss->ss_last < IEEE80211_SCAN_MAX) 574 ss->ss_chans[ss->ss_last++] = c; 575 } 576 577 static void 578 makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 579 const struct scanlist table[]) 580 { 581 const struct scanlist *scan; 582 enum ieee80211_phymode mode; 583 584 ss->ss_last = 0; 585 /* 586 * Use the table of ordered channels to construct the list 587 * of channels for scanning. Any channels in the ordered 588 * list not in the master list will be discarded. 589 */ 590 for (scan = table; scan->list != NULL; scan++) { 591 mode = scan->mode; 592 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { 593 /* 594 * If a desired mode was specified, scan only 595 * channels that satisfy that constraint. 596 */ 597 if (vap->iv_des_mode != mode) { 598 /* 599 * The scan table marks 2.4Ghz channels as b 600 * so if the desired mode is 11g, then use 601 * the 11b channel list but upgrade the mode. 602 */ 603 if (vap->iv_des_mode != IEEE80211_MODE_11G || 604 mode != IEEE80211_MODE_11B) 605 continue; 606 mode = IEEE80211_MODE_11G; /* upgrade */ 607 } 608 } else { 609 /* 610 * This lets add_channels upgrade an 11b channel 611 * to 11g if available. 612 */ 613 if (mode == IEEE80211_MODE_11B) 614 mode = IEEE80211_MODE_AUTO; 615 } 616 #ifdef IEEE80211_F_XR 617 /* XR does not operate on turbo channels */ 618 if ((vap->iv_flags & IEEE80211_F_XR) && 619 (mode == IEEE80211_MODE_TURBO_A || 620 mode == IEEE80211_MODE_TURBO_G || 621 mode == IEEE80211_MODE_STURBO_A)) 622 continue; 623 #endif 624 /* 625 * Add the list of the channels; any that are not 626 * in the master channel list will be discarded. 627 */ 628 add_channels(vap, ss, mode, scan->list, scan->count); 629 } 630 631 /* 632 * Add the channels from the ic that are not present 633 * in the table. 634 */ 635 sweepchannels(ss, vap, table); 636 } 637 638 static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 639 { 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 640 static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 641 { 5170, 5190, 5210, 5230 }; 642 static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 643 { 2412, 2437, 2462, 2442, 2472 }; 644 static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 645 { 5745, 5765, 5785, 5805, 5825 }; 646 static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 647 { 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 648 static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 649 { 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 650 static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 651 { 2484 }; 652 static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 653 { 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 654 static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 655 { 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 656 #ifdef ATH_TURBO_SCAN 657 static const uint16_t rcl5[] = /* 3 static turbo channels */ 658 { 5210, 5250, 5290 }; 659 static const uint16_t rcl6[] = /* 2 static turbo channels */ 660 { 5760, 5800 }; 661 static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 662 { 5540, 5580, 5620, 5660 }; 663 static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 664 { 2437 }; 665 static const uint16_t rcl13[] = /* dynamic Turbo channels */ 666 { 5200, 5240, 5280, 5765, 5805 }; 667 #endif /* ATH_TURBO_SCAN */ 668 669 #define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 670 671 static const struct scanlist staScanTable[] = { 672 { IEEE80211_MODE_11B, X(rcl3) }, 673 { IEEE80211_MODE_11A, X(rcl1) }, 674 { IEEE80211_MODE_11A, X(rcl2) }, 675 { IEEE80211_MODE_11B, X(rcl8) }, 676 { IEEE80211_MODE_11B, X(rcl9) }, 677 { IEEE80211_MODE_11A, X(rcl4) }, 678 #ifdef ATH_TURBO_SCAN 679 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 680 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 681 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 682 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 683 #endif /* ATH_TURBO_SCAN */ 684 { IEEE80211_MODE_11A, X(rcl7) }, 685 { IEEE80211_MODE_11B, X(rcl10) }, 686 { IEEE80211_MODE_11A, X(rcl11) }, 687 #ifdef ATH_TURBO_SCAN 688 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 689 #endif /* ATH_TURBO_SCAN */ 690 { .list = NULL } 691 }; 692 693 /* 694 * Start a station-mode scan by populating the channel list. 695 */ 696 static int 697 sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 698 { 699 struct sta_table *st = ss->ss_priv; 700 701 makescanlist(ss, vap, staScanTable); 702 703 if (ss->ss_mindwell == 0) 704 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 705 if (ss->ss_maxdwell == 0) 706 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 707 708 st->st_scangen++; 709 st->st_newscan = 1; 710 711 return 0; 712 } 713 714 /* 715 * Restart a scan, typically a bg scan but can 716 * also be a fg scan that came up empty. 717 */ 718 static int 719 sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 720 { 721 struct sta_table *st = ss->ss_priv; 722 723 st->st_newscan = 1; 724 return 0; 725 } 726 727 /* 728 * Cancel an ongoing scan. 729 */ 730 static int 731 sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 732 { 733 return 0; 734 } 735 736 /* unalligned little endian access */ 737 #define LE_READ_2(p) \ 738 ((uint16_t) \ 739 ((((const uint8_t *)(p))[0] ) | \ 740 (((const uint8_t *)(p))[1] << 8))) 741 742 /* 743 * Demote any supplied 11g channel to 11b. There should 744 * always be an 11b channel but we check anyway... 745 */ 746 static struct ieee80211_channel * 747 demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 748 { 749 struct ieee80211_channel *c; 750 751 if (IEEE80211_IS_CHAN_ANYG(chan) && 752 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 753 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 754 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 755 IEEE80211_CHAN_B); 756 if (c != NULL) 757 chan = c; 758 } 759 return chan; 760 } 761 762 static int 763 maxrate(const struct ieee80211_scan_entry *se) 764 { 765 const struct ieee80211_ie_htcap *htcap = 766 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 767 int rmax, r, i, txstream; 768 uint16_t caps; 769 uint8_t txparams; 770 771 rmax = 0; 772 if (htcap != NULL) { 773 /* 774 * HT station; inspect supported MCS and then adjust 775 * rate by channel width. 776 */ 777 txparams = htcap->hc_mcsset[12]; 778 if (txparams & 0x3) { 779 /* 780 * TX MCS parameters defined and not equal to RX, 781 * extract the number of spartial streams and 782 * map it to the highest MCS rate. 783 */ 784 txstream = ((txparams & 0xc) >> 2) + 1; 785 i = txstream * 8 - 1; 786 } else 787 for (i = 31; i >= 0 && isclr(htcap->hc_mcsset, i); i--); 788 if (i >= 0) { 789 caps = LE_READ_2(&htcap->hc_cap); 790 if ((caps & IEEE80211_HTCAP_CHWIDTH40) && 791 (caps & IEEE80211_HTCAP_SHORTGI40)) 792 rmax = ieee80211_htrates[i].ht40_rate_400ns; 793 else if (caps & IEEE80211_HTCAP_CHWIDTH40) 794 rmax = ieee80211_htrates[i].ht40_rate_800ns; 795 else if (caps & IEEE80211_HTCAP_SHORTGI20) 796 rmax = ieee80211_htrates[i].ht20_rate_400ns; 797 else 798 rmax = ieee80211_htrates[i].ht20_rate_800ns; 799 } 800 } 801 for (i = 0; i < se->se_rates[1]; i++) { 802 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 803 if (r > rmax) 804 rmax = r; 805 } 806 for (i = 0; i < se->se_xrates[1]; i++) { 807 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 808 if (r > rmax) 809 rmax = r; 810 } 811 return rmax; 812 } 813 814 /* 815 * Compare the capabilities of two entries and decide which is 816 * more desirable (return >0 if a is considered better). Note 817 * that we assume compatibility/usability has already been checked 818 * so we don't need to (e.g. validate whether privacy is supported). 819 * Used to select the best scan candidate for association in a BSS. 820 */ 821 static int 822 sta_compare(const struct sta_entry *a, const struct sta_entry *b) 823 { 824 #define PREFER(_a,_b,_what) do { \ 825 if (((_a) ^ (_b)) & (_what)) \ 826 return ((_a) & (_what)) ? 1 : -1; \ 827 } while (0) 828 int maxa, maxb; 829 int8_t rssia, rssib; 830 int weight; 831 832 /* privacy support */ 833 PREFER(a->base.se_capinfo, b->base.se_capinfo, 834 IEEE80211_CAPINFO_PRIVACY); 835 836 /* compare count of previous failures */ 837 weight = b->se_fails - a->se_fails; 838 if (abs(weight) > 1) 839 return weight; 840 841 /* 842 * Compare rssi. If the two are considered equivalent 843 * then fallback to other criteria. We threshold the 844 * comparisons to avoid selecting an ap purely by rssi 845 * when both values may be good but one ap is otherwise 846 * more desirable (e.g. an 11b-only ap with stronger 847 * signal than an 11g ap). 848 */ 849 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 850 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 851 if (abs(rssib - rssia) < 5) { 852 /* best/max rate preferred if signal level close enough XXX */ 853 maxa = maxrate(&a->base); 854 maxb = maxrate(&b->base); 855 if (maxa != maxb) 856 return maxa - maxb; 857 /* XXX use freq for channel preference */ 858 /* for now just prefer 5Ghz band to all other bands */ 859 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 860 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 861 } 862 /* all things being equal, use signal level */ 863 return a->base.se_rssi - b->base.se_rssi; 864 #undef PREFER 865 } 866 867 /* 868 * Check rate set suitability and return the best supported rate. 869 * XXX inspect MCS for HT 870 */ 871 static int 872 check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 873 const struct ieee80211_scan_entry *se) 874 { 875 #define RV(v) ((v) & IEEE80211_RATE_VAL) 876 const struct ieee80211_rateset *srs; 877 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 878 const uint8_t *rs; 879 880 okrate = badrate = 0; 881 882 srs = ieee80211_get_suprates(vap->iv_ic, chan); 883 nrs = se->se_rates[1]; 884 rs = se->se_rates+2; 885 /* XXX MCS */ 886 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 887 fixedrate = IEEE80211_FIXED_RATE_NONE; 888 again: 889 for (i = 0; i < nrs; i++) { 890 r = RV(rs[i]); 891 badrate = r; 892 /* 893 * Check any fixed rate is included. 894 */ 895 if (r == ucastrate) 896 fixedrate = r; 897 /* 898 * Check against our supported rates. 899 */ 900 for (j = 0; j < srs->rs_nrates; j++) 901 if (r == RV(srs->rs_rates[j])) { 902 if (r > okrate) /* NB: track max */ 903 okrate = r; 904 break; 905 } 906 907 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 908 /* 909 * Don't try joining a BSS, if we don't support 910 * one of its basic rates. 911 */ 912 okrate = 0; 913 goto back; 914 } 915 } 916 if (rs == se->se_rates+2) { 917 /* scan xrates too; sort of an algol68-style for loop */ 918 nrs = se->se_xrates[1]; 919 rs = se->se_xrates+2; 920 goto again; 921 } 922 923 back: 924 if (okrate == 0 || ucastrate != fixedrate) 925 return badrate | IEEE80211_RATE_BASIC; 926 else 927 return RV(okrate); 928 #undef RV 929 } 930 931 static __inline int 932 match_id(const uint8_t *ie, const uint8_t *val, int len) 933 { 934 return (ie[1] == len && memcmp(ie+2, val, len) == 0); 935 } 936 937 static int 938 match_ssid(const uint8_t *ie, 939 int nssid, const struct ieee80211_scan_ssid ssids[]) 940 { 941 int i; 942 943 for (i = 0; i < nssid; i++) { 944 if (match_id(ie, ssids[i].ssid, ssids[i].len)) 945 return 1; 946 } 947 return 0; 948 } 949 950 #ifdef IEEE80211_SUPPORT_TDMA 951 static int 952 tdma_isfull(const struct ieee80211_tdma_param *tdma) 953 { 954 int slot, slotcnt; 955 956 slotcnt = tdma->tdma_slotcnt; 957 for (slot = slotcnt-1; slot >= 0; slot--) 958 if (isclr(tdma->tdma_inuse, slot)) 959 return 0; 960 return 1; 961 } 962 #endif /* IEEE80211_SUPPORT_TDMA */ 963 964 /* 965 * Test a scan candidate for suitability/compatibility. 966 */ 967 static int 968 match_bss(struct ieee80211vap *vap, 969 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 970 int debug) 971 { 972 struct ieee80211com *ic = vap->iv_ic; 973 struct ieee80211_scan_entry *se = &se0->base; 974 uint8_t rate; 975 int fail; 976 977 fail = 0; 978 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 979 fail |= MATCH_CHANNEL; 980 /* 981 * NB: normally the desired mode is used to construct 982 * the channel list, but it's possible for the scan 983 * cache to include entries for stations outside this 984 * list so we check the desired mode here to weed them 985 * out. 986 */ 987 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 988 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 989 chanflags[vap->iv_des_mode]) 990 fail |= MATCH_CHANNEL; 991 if (vap->iv_opmode == IEEE80211_M_IBSS) { 992 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 993 fail |= MATCH_CAPINFO; 994 #ifdef IEEE80211_SUPPORT_TDMA 995 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { 996 /* 997 * Adhoc demo network setup shouldn't really be scanning 998 * but just in case skip stations operating in IBSS or 999 * BSS mode. 1000 */ 1001 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1002 fail |= MATCH_CAPINFO; 1003 /* 1004 * TDMA operation cannot coexist with a normal 802.11 network; 1005 * skip if IBSS or ESS capabilities are marked and require 1006 * the beacon have a TDMA ie present. 1007 */ 1008 if (vap->iv_caps & IEEE80211_C_TDMA) { 1009 const struct ieee80211_tdma_param *tdma = 1010 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; 1011 const struct ieee80211_tdma_state *ts = vap->iv_tdma; 1012 1013 if (tdma == NULL) 1014 fail |= MATCH_TDMA_NOIE; 1015 else if (tdma->tdma_version != ts->tdma_version) 1016 fail |= MATCH_TDMA_VERSION; 1017 else if (tdma->tdma_slot != 0) 1018 fail |= MATCH_TDMA_NOTMASTER; 1019 else if (tdma_isfull(tdma)) 1020 fail |= MATCH_TDMA_NOSLOT; 1021 #if 0 1022 else if (ieee80211_local_address(se->se_macaddr)) 1023 fail |= MATCH_TDMA_LOCAL; 1024 #endif 1025 } 1026 #endif /* IEEE80211_SUPPORT_TDMA */ 1027 #ifdef IEEE80211_SUPPORT_MESH 1028 } else if (vap->iv_opmode == IEEE80211_M_MBSS) { 1029 const struct ieee80211_mesh_state *ms = vap->iv_mesh; 1030 /* 1031 * Mesh nodes have IBSS & ESS bits in capinfo turned off 1032 * and two special ie's that must be present. 1033 */ 1034 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1035 fail |= MATCH_CAPINFO; 1036 else if (se->se_meshid[0] != IEEE80211_ELEMID_MESHID) 1037 fail |= MATCH_MESH_NOID; 1038 else if (ms->ms_idlen != 0 && 1039 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) 1040 fail |= MATCH_MESHID; 1041 #endif 1042 } else { 1043 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 1044 fail |= MATCH_CAPINFO; 1045 /* 1046 * If 11d is enabled and we're attempting to join a bss 1047 * that advertises it's country code then compare our 1048 * current settings to what we fetched from the country ie. 1049 * If our country code is unspecified or different then do 1050 * not attempt to join the bss. We should have already 1051 * dispatched an event to user space that identifies the 1052 * new country code so our regdomain config should match. 1053 */ 1054 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 1055 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 1056 se->se_cc[0] != 0 && 1057 (ic->ic_regdomain.country == CTRY_DEFAULT || 1058 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 1059 fail |= MATCH_CC; 1060 } 1061 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 1062 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 1063 fail |= MATCH_PRIVACY; 1064 } else { 1065 /* XXX does this mean privacy is supported or required? */ 1066 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 1067 fail |= MATCH_PRIVACY; 1068 } 1069 se0->se_flags &= ~STA_DEMOTE11B; 1070 rate = check_rate(vap, se->se_chan, se); 1071 if (rate & IEEE80211_RATE_BASIC) { 1072 fail |= MATCH_RATE; 1073 /* 1074 * An 11b-only ap will give a rate mismatch if there is an 1075 * OFDM fixed tx rate for 11g. Try downgrading the channel 1076 * in the scan list to 11b and retry the rate check. 1077 */ 1078 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 1079 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 1080 if ((rate & IEEE80211_RATE_BASIC) == 0) { 1081 fail &= ~MATCH_RATE; 1082 se0->se_flags |= STA_DEMOTE11B; 1083 } 1084 } 1085 } else if (rate < 2*24) { 1086 /* 1087 * This is an 11b-only ap. Check the desired mode in 1088 * case that needs to be honored (mode 11g filters out 1089 * 11b-only ap's). Otherwise force any 11g channel used 1090 * in scanning to be demoted. 1091 * 1092 * NB: we cheat a bit here by looking at the max rate; 1093 * we could/should check the rates. 1094 */ 1095 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 1096 vap->iv_des_mode == IEEE80211_MODE_11B)) 1097 fail |= MATCH_RATE; 1098 else 1099 se0->se_flags |= STA_DEMOTE11B; 1100 } 1101 if (ss->ss_nssid != 0 && 1102 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 1103 fail |= MATCH_SSID; 1104 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 1105 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 1106 fail |= MATCH_BSSID; 1107 if (se0->se_fails >= STA_FAILS_MAX) 1108 fail |= MATCH_FAILS; 1109 if (se0->se_notseen >= STA_PURGE_SCANS) 1110 fail |= MATCH_NOTSEEN; 1111 if (se->se_rssi < STA_RSSI_MIN) 1112 fail |= MATCH_RSSI; 1113 #ifdef IEEE80211_DEBUG 1114 if (ieee80211_msg(vap, debug)) { 1115 printf(" %c %s", 1116 fail & MATCH_FAILS ? '=' : 1117 fail & MATCH_NOTSEEN ? '^' : 1118 fail & MATCH_CC ? '$' : 1119 #ifdef IEEE80211_SUPPORT_TDMA 1120 fail & MATCH_TDMA_NOIE ? '&' : 1121 fail & MATCH_TDMA_VERSION ? 'v' : 1122 fail & MATCH_TDMA_NOTMASTER ? 's' : 1123 fail & MATCH_TDMA_NOSLOT ? 'f' : 1124 fail & MATCH_TDMA_LOCAL ? 'l' : 1125 #endif 1126 fail & MATCH_MESH_NOID ? 'm' : 1127 fail ? '-' : '+', ether_sprintf(se->se_macaddr)); 1128 printf(" %s%c", ether_sprintf(se->se_bssid), 1129 fail & MATCH_BSSID ? '!' : ' '); 1130 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 1131 fail & MATCH_CHANNEL ? '!' : ' '); 1132 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 1133 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 1134 fail & MATCH_RATE ? '!' : ' '); 1135 printf(" %4s%c", 1136 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 1137 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", 1138 fail & MATCH_CAPINFO ? '!' : ' '); 1139 printf(" %3s%c ", 1140 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 1141 "wep" : "no", 1142 fail & MATCH_PRIVACY ? '!' : ' '); 1143 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 1144 printf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); 1145 } 1146 #endif 1147 return fail; 1148 } 1149 1150 static void 1151 sta_update_notseen(struct sta_table *st) 1152 { 1153 struct sta_entry *se; 1154 1155 IEEE80211_SCAN_TABLE_LOCK(st); 1156 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1157 /* 1158 * If seen the reset and don't bump the count; 1159 * otherwise bump the ``not seen'' count. Note 1160 * that this insures that stations for which we 1161 * see frames while not scanning but not during 1162 * this scan will not be penalized. 1163 */ 1164 if (se->se_seen) 1165 se->se_seen = 0; 1166 else 1167 se->se_notseen++; 1168 } 1169 IEEE80211_SCAN_TABLE_UNLOCK(st); 1170 } 1171 1172 static void 1173 sta_dec_fails(struct sta_table *st) 1174 { 1175 struct sta_entry *se; 1176 1177 IEEE80211_SCAN_TABLE_LOCK(st); 1178 TAILQ_FOREACH(se, &st->st_entry, se_list) 1179 if (se->se_fails) 1180 se->se_fails--; 1181 IEEE80211_SCAN_TABLE_UNLOCK(st); 1182 } 1183 1184 static struct sta_entry * 1185 select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1186 { 1187 struct sta_table *st = ss->ss_priv; 1188 struct sta_entry *se, *selbs = NULL; 1189 1190 IEEE80211_DPRINTF(vap, debug, " %s\n", 1191 "macaddr bssid chan rssi rate flag wep essid"); 1192 IEEE80211_SCAN_TABLE_LOCK(st); 1193 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1194 ieee80211_ies_expand(&se->base.se_ies); 1195 if (match_bss(vap, ss, se, debug) == 0) { 1196 if (selbs == NULL) 1197 selbs = se; 1198 else if (sta_compare(se, selbs) > 0) 1199 selbs = se; 1200 } 1201 } 1202 IEEE80211_SCAN_TABLE_UNLOCK(st); 1203 1204 return selbs; 1205 } 1206 1207 /* 1208 * Pick an ap or ibss network to join or find a channel 1209 * to use to start an ibss network. 1210 */ 1211 static int 1212 sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1213 { 1214 struct sta_table *st = ss->ss_priv; 1215 struct sta_entry *selbs; 1216 struct ieee80211_channel *chan; 1217 1218 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1219 ("wrong mode %u", vap->iv_opmode)); 1220 1221 if (st->st_newscan) { 1222 sta_update_notseen(st); 1223 st->st_newscan = 0; 1224 } 1225 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1226 /* 1227 * Manual/background scan, don't select+join the 1228 * bss, just return. The scanning framework will 1229 * handle notification that this has completed. 1230 */ 1231 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1232 return 1; 1233 } 1234 /* 1235 * Automatic sequencing; look for a candidate and 1236 * if found join the network. 1237 */ 1238 /* NB: unlocked read should be ok */ 1239 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1240 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1241 "%s: no scan candidate\n", __func__); 1242 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1243 return 0; 1244 notfound: 1245 /* 1246 * If nothing suitable was found decrement 1247 * the failure counts so entries will be 1248 * reconsidered the next time around. We 1249 * really want to do this only for sta's 1250 * where we've previously had some success. 1251 */ 1252 sta_dec_fails(st); 1253 st->st_newscan = 1; 1254 return 0; /* restart scan */ 1255 } 1256 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1257 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1258 return (selbs != NULL); 1259 if (selbs == NULL) 1260 goto notfound; 1261 chan = selbs->base.se_chan; 1262 if (selbs->se_flags & STA_DEMOTE11B) 1263 chan = demote11b(vap, chan); 1264 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1265 goto notfound; 1266 return 1; /* terminate scan */ 1267 } 1268 1269 /* 1270 * Lookup an entry in the scan cache. We assume we're 1271 * called from the bottom half or such that we don't need 1272 * to block the bottom half so that it's safe to return 1273 * a reference to an entry w/o holding the lock on the table. 1274 */ 1275 static struct sta_entry * 1276 sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1277 { 1278 struct sta_entry *se; 1279 int hash = STA_HASH(macaddr); 1280 1281 IEEE80211_SCAN_TABLE_LOCK(st); 1282 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1283 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1284 break; 1285 IEEE80211_SCAN_TABLE_UNLOCK(st); 1286 1287 return se; /* NB: unlocked */ 1288 } 1289 1290 static void 1291 sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1292 { 1293 struct ieee80211com *ic = vap->iv_ic; 1294 struct ieee80211_node *ni = vap->iv_bss; 1295 struct sta_table *st = ss->ss_priv; 1296 enum ieee80211_phymode mode; 1297 struct sta_entry *se, *selbs; 1298 uint8_t roamRate, curRate, ucastRate; 1299 int8_t roamRssi, curRssi; 1300 1301 se = sta_lookup(st, ni->ni_macaddr); 1302 if (se == NULL) { 1303 /* XXX something is wrong */ 1304 return; 1305 } 1306 1307 mode = ieee80211_chan2mode(ic->ic_bsschan); 1308 roamRate = vap->iv_roamparms[mode].rate; 1309 roamRssi = vap->iv_roamparms[mode].rssi; 1310 ucastRate = vap->iv_txparms[mode].ucastrate; 1311 /* NB: the most up to date rssi is in the node, not the scan cache */ 1312 curRssi = ic->ic_node_getrssi(ni); 1313 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1314 curRate = ni->ni_txrate; 1315 roamRate &= IEEE80211_RATE_VAL; 1316 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1317 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1318 __func__, curRssi, curRate, roamRssi, roamRate); 1319 } else { 1320 curRate = roamRate; /* NB: insure compare below fails */ 1321 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1322 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1323 } 1324 /* 1325 * Check if a new ap should be used and switch. 1326 * XXX deauth current ap 1327 */ 1328 if (curRate < roamRate || curRssi < roamRssi) { 1329 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1330 /* 1331 * Scan cache contents are too old; force a scan now 1332 * if possible so we have current state to make a 1333 * decision with. We don't kick off a bg scan if 1334 * we're using dynamic turbo and boosted or if the 1335 * channel is busy. 1336 * XXX force immediate switch on scan complete 1337 */ 1338 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1339 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) 1340 ieee80211_bg_scan(vap, 0); 1341 return; 1342 } 1343 se->base.se_rssi = curRssi; 1344 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1345 if (selbs != NULL && selbs != se) { 1346 struct ieee80211_channel *chan; 1347 1348 IEEE80211_DPRINTF(vap, 1349 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1350 "%s: ROAM: curRate %u, roamRate %u, " 1351 "curRssi %d, roamRssi %d\n", __func__, 1352 curRate, roamRate, curRssi, roamRssi); 1353 1354 chan = selbs->base.se_chan; 1355 if (selbs->se_flags & STA_DEMOTE11B) 1356 chan = demote11b(vap, chan); 1357 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1358 } 1359 } 1360 } 1361 1362 /* 1363 * Age entries in the scan cache. 1364 * XXX also do roaming since it's convenient 1365 */ 1366 static void 1367 sta_age(struct ieee80211_scan_state *ss) 1368 { 1369 struct ieee80211vap *vap = ss->ss_vap; 1370 1371 adhoc_age(ss); 1372 /* 1373 * If rate control is enabled check periodically to see if 1374 * we should roam from our current connection to one that 1375 * might be better. This only applies when we're operating 1376 * in sta mode and automatic roaming is set. 1377 * XXX defer if busy 1378 * XXX repeater station 1379 * XXX do when !bgscan? 1380 */ 1381 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1382 ("wrong mode %u", vap->iv_opmode)); 1383 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1384 (vap->iv_flags & IEEE80211_F_BGSCAN) && 1385 vap->iv_state >= IEEE80211_S_RUN) 1386 /* XXX vap is implicit */ 1387 sta_roam_check(ss, vap); 1388 } 1389 1390 /* 1391 * Iterate over the entries in the scan cache, invoking 1392 * the callback function on each one. 1393 */ 1394 static void 1395 sta_iterate(struct ieee80211_scan_state *ss, 1396 ieee80211_scan_iter_func *f, void *arg) 1397 { 1398 struct sta_table *st = ss->ss_priv; 1399 struct sta_entry *se; 1400 u_int gen; 1401 1402 mtx_lock(&st->st_scanlock); 1403 gen = st->st_scaniter++; 1404 restart: 1405 IEEE80211_SCAN_TABLE_LOCK(st); 1406 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1407 if (se->se_scangen != gen) { 1408 se->se_scangen = gen; 1409 /* update public state */ 1410 se->base.se_age = ticks - se->se_lastupdate; 1411 IEEE80211_SCAN_TABLE_UNLOCK(st); 1412 (*f)(arg, &se->base); 1413 goto restart; 1414 } 1415 } 1416 IEEE80211_SCAN_TABLE_UNLOCK(st); 1417 1418 mtx_unlock(&st->st_scanlock); 1419 } 1420 1421 static void 1422 sta_assoc_fail(struct ieee80211_scan_state *ss, 1423 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1424 { 1425 struct sta_table *st = ss->ss_priv; 1426 struct sta_entry *se; 1427 1428 se = sta_lookup(st, macaddr); 1429 if (se != NULL) { 1430 se->se_fails++; 1431 se->se_lastfail = ticks; 1432 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1433 macaddr, "%s: reason %u fails %u", 1434 __func__, reason, se->se_fails); 1435 } 1436 } 1437 1438 static void 1439 sta_assoc_success(struct ieee80211_scan_state *ss, 1440 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1441 { 1442 struct sta_table *st = ss->ss_priv; 1443 struct sta_entry *se; 1444 1445 se = sta_lookup(st, macaddr); 1446 if (se != NULL) { 1447 #if 0 1448 se->se_fails = 0; 1449 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1450 macaddr, "%s: fails %u", 1451 __func__, se->se_fails); 1452 #endif 1453 se->se_lastassoc = ticks; 1454 } 1455 } 1456 1457 static const struct ieee80211_scanner sta_default = { 1458 .scan_name = "default", 1459 .scan_attach = sta_attach, 1460 .scan_detach = sta_detach, 1461 .scan_start = sta_start, 1462 .scan_restart = sta_restart, 1463 .scan_cancel = sta_cancel, 1464 .scan_end = sta_pick_bss, 1465 .scan_flush = sta_flush, 1466 .scan_add = sta_add, 1467 .scan_age = sta_age, 1468 .scan_iterate = sta_iterate, 1469 .scan_assoc_fail = sta_assoc_fail, 1470 .scan_assoc_success = sta_assoc_success, 1471 }; 1472 1473 /* 1474 * Adhoc mode-specific support. 1475 */ 1476 1477 static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1478 { 5180, 5200, 5220, 5240 }; 1479 static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1480 { 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1481 static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1482 { 5170, 5190, 5210, 5230 }; 1483 static const uint16_t adhoc11b[] = /* 10, 11 */ 1484 { 2457, 2462 }; 1485 1486 static const struct scanlist adhocScanTable[] = { 1487 { IEEE80211_MODE_11B, X(adhoc11b) }, 1488 { IEEE80211_MODE_11A, X(adhocWorld) }, 1489 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1490 { IEEE80211_MODE_11B, X(adhocMkk) }, 1491 { .list = NULL } 1492 }; 1493 #undef X 1494 1495 /* 1496 * Start an adhoc-mode scan by populating the channel list. 1497 */ 1498 static int 1499 adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1500 { 1501 struct sta_table *st = ss->ss_priv; 1502 1503 makescanlist(ss, vap, adhocScanTable); 1504 1505 if (ss->ss_mindwell == 0) 1506 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1507 if (ss->ss_maxdwell == 0) 1508 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1509 1510 st->st_scangen++; 1511 st->st_newscan = 1; 1512 1513 return 0; 1514 } 1515 1516 /* 1517 * Select a channel to start an adhoc network on. 1518 * The channel list was populated with appropriate 1519 * channels so select one that looks least occupied. 1520 */ 1521 static struct ieee80211_channel * 1522 adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1523 { 1524 struct sta_table *st = ss->ss_priv; 1525 struct sta_entry *se; 1526 struct ieee80211_channel *c, *bestchan; 1527 int i, bestrssi, maxrssi; 1528 1529 bestchan = NULL; 1530 bestrssi = -1; 1531 1532 IEEE80211_SCAN_TABLE_LOCK(st); 1533 for (i = 0; i < ss->ss_last; i++) { 1534 c = ss->ss_chans[i]; 1535 /* never consider a channel with radar */ 1536 if (IEEE80211_IS_CHAN_RADAR(c)) 1537 continue; 1538 /* skip channels disallowed by regulatory settings */ 1539 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1540 continue; 1541 /* check channel attributes for band compatibility */ 1542 if (flags != 0 && (c->ic_flags & flags) != flags) 1543 continue; 1544 maxrssi = 0; 1545 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1546 if (se->base.se_chan != c) 1547 continue; 1548 if (se->base.se_rssi > maxrssi) 1549 maxrssi = se->base.se_rssi; 1550 } 1551 if (bestchan == NULL || maxrssi < bestrssi) 1552 bestchan = c; 1553 } 1554 IEEE80211_SCAN_TABLE_UNLOCK(st); 1555 1556 return bestchan; 1557 } 1558 1559 /* 1560 * Pick an ibss network to join or find a channel 1561 * to use to start an ibss network. 1562 */ 1563 static int 1564 adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1565 { 1566 struct sta_table *st = ss->ss_priv; 1567 struct sta_entry *selbs; 1568 struct ieee80211_channel *chan; 1569 1570 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1571 vap->iv_opmode == IEEE80211_M_AHDEMO || 1572 vap->iv_opmode == IEEE80211_M_MBSS, 1573 ("wrong opmode %u", vap->iv_opmode)); 1574 1575 if (st->st_newscan) { 1576 sta_update_notseen(st); 1577 st->st_newscan = 0; 1578 } 1579 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1580 /* 1581 * Manual/background scan, don't select+join the 1582 * bss, just return. The scanning framework will 1583 * handle notification that this has completed. 1584 */ 1585 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1586 return 1; 1587 } 1588 /* 1589 * Automatic sequencing; look for a candidate and 1590 * if found join the network. 1591 */ 1592 /* NB: unlocked read should be ok */ 1593 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1594 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1595 "%s: no scan candidate\n", __func__); 1596 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1597 return 0; 1598 notfound: 1599 /* NB: never auto-start a tdma network for slot !0 */ 1600 #ifdef IEEE80211_SUPPORT_TDMA 1601 if (vap->iv_des_nssid && 1602 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || 1603 ieee80211_tdma_getslot(vap) == 0)) { 1604 #else 1605 if (vap->iv_des_nssid) { 1606 #endif 1607 /* 1608 * No existing adhoc network to join and we have 1609 * an ssid; start one up. If no channel was 1610 * specified, try to select a channel. 1611 */ 1612 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1613 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1614 struct ieee80211com *ic = vap->iv_ic; 1615 1616 chan = adhoc_pick_channel(ss, 0); 1617 if (chan != NULL) 1618 chan = ieee80211_ht_adjust_channel(ic, 1619 chan, vap->iv_flags_ht); 1620 } else 1621 chan = vap->iv_des_chan; 1622 if (chan != NULL) { 1623 ieee80211_create_ibss(vap, chan); 1624 return 1; 1625 } 1626 } 1627 /* 1628 * If nothing suitable was found decrement 1629 * the failure counts so entries will be 1630 * reconsidered the next time around. We 1631 * really want to do this only for sta's 1632 * where we've previously had some success. 1633 */ 1634 sta_dec_fails(st); 1635 st->st_newscan = 1; 1636 return 0; /* restart scan */ 1637 } 1638 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1639 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1640 return (selbs != NULL); 1641 if (selbs == NULL) 1642 goto notfound; 1643 chan = selbs->base.se_chan; 1644 if (selbs->se_flags & STA_DEMOTE11B) 1645 chan = demote11b(vap, chan); 1646 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1647 goto notfound; 1648 return 1; /* terminate scan */ 1649 } 1650 1651 /* 1652 * Age entries in the scan cache. 1653 */ 1654 static void 1655 adhoc_age(struct ieee80211_scan_state *ss) 1656 { 1657 struct sta_table *st = ss->ss_priv; 1658 struct sta_entry *se, *next; 1659 1660 IEEE80211_SCAN_TABLE_LOCK(st); 1661 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 1662 if (se->se_notseen > STA_PURGE_SCANS) { 1663 TAILQ_REMOVE(&st->st_entry, se, se_list); 1664 LIST_REMOVE(se, se_hash); 1665 ieee80211_ies_cleanup(&se->base.se_ies); 1666 free(se, M_80211_SCAN); 1667 } 1668 } 1669 IEEE80211_SCAN_TABLE_UNLOCK(st); 1670 } 1671 1672 static const struct ieee80211_scanner adhoc_default = { 1673 .scan_name = "default", 1674 .scan_attach = sta_attach, 1675 .scan_detach = sta_detach, 1676 .scan_start = adhoc_start, 1677 .scan_restart = sta_restart, 1678 .scan_cancel = sta_cancel, 1679 .scan_end = adhoc_pick_bss, 1680 .scan_flush = sta_flush, 1681 .scan_pickchan = adhoc_pick_channel, 1682 .scan_add = sta_add, 1683 .scan_age = adhoc_age, 1684 .scan_iterate = sta_iterate, 1685 .scan_assoc_fail = sta_assoc_fail, 1686 .scan_assoc_success = sta_assoc_success, 1687 }; 1688 IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1689 IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1690 1691 static void 1692 ap_force_promisc(struct ieee80211com *ic) 1693 { 1694 struct ifnet *ifp = ic->ic_ifp; 1695 1696 IEEE80211_LOCK(ic); 1697 /* set interface into promiscuous mode */ 1698 ifp->if_flags |= IFF_PROMISC; 1699 ieee80211_runtask(ic, &ic->ic_promisc_task); 1700 IEEE80211_UNLOCK(ic); 1701 } 1702 1703 static void 1704 ap_reset_promisc(struct ieee80211com *ic) 1705 { 1706 IEEE80211_LOCK(ic); 1707 ieee80211_syncifflag_locked(ic, IFF_PROMISC); 1708 IEEE80211_UNLOCK(ic); 1709 } 1710 1711 static int 1712 ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1713 { 1714 struct sta_table *st = ss->ss_priv; 1715 1716 makescanlist(ss, vap, staScanTable); 1717 1718 if (ss->ss_mindwell == 0) 1719 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1720 if (ss->ss_maxdwell == 0) 1721 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1722 1723 st->st_scangen++; 1724 st->st_newscan = 1; 1725 1726 ap_force_promisc(vap->iv_ic); 1727 return 0; 1728 } 1729 1730 /* 1731 * Cancel an ongoing scan. 1732 */ 1733 static int 1734 ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1735 { 1736 ap_reset_promisc(vap->iv_ic); 1737 return 0; 1738 } 1739 1740 /* 1741 * Pick a quiet channel to use for ap operation. 1742 */ 1743 static struct ieee80211_channel * 1744 ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1745 { 1746 struct sta_table *st = ss->ss_priv; 1747 struct ieee80211_channel *bestchan = NULL; 1748 int i; 1749 1750 /* XXX select channel more intelligently, e.g. channel spread, power */ 1751 /* NB: use scan list order to preserve channel preference */ 1752 for (i = 0; i < ss->ss_last; i++) { 1753 struct ieee80211_channel *chan = ss->ss_chans[i]; 1754 /* 1755 * If the channel is unoccupied the max rssi 1756 * should be zero; just take it. Otherwise 1757 * track the channel with the lowest rssi and 1758 * use that when all channels appear occupied. 1759 */ 1760 if (IEEE80211_IS_CHAN_RADAR(chan)) 1761 continue; 1762 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1763 continue; 1764 /* check channel attributes for band compatibility */ 1765 if (flags != 0 && (chan->ic_flags & flags) != flags) 1766 continue; 1767 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); 1768 /* XXX channel have interference */ 1769 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1770 /* XXX use other considerations */ 1771 return chan; 1772 } 1773 if (bestchan == NULL || 1774 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1775 bestchan = chan; 1776 } 1777 return bestchan; 1778 } 1779 1780 /* 1781 * Pick a quiet channel to use for ap operation. 1782 */ 1783 static int 1784 ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1785 { 1786 struct ieee80211com *ic = vap->iv_ic; 1787 struct ieee80211_channel *bestchan; 1788 1789 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1790 ("wrong opmode %u", vap->iv_opmode)); 1791 bestchan = ap_pick_channel(ss, 0); 1792 if (bestchan == NULL) { 1793 /* no suitable channel, should not happen */ 1794 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1795 "%s: no suitable channel! (should not happen)\n", __func__); 1796 /* XXX print something? */ 1797 return 0; /* restart scan */ 1798 } 1799 /* 1800 * If this is a dynamic turbo channel, start with the unboosted one. 1801 */ 1802 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1803 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1804 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1805 if (bestchan == NULL) { 1806 /* should never happen ?? */ 1807 return 0; 1808 } 1809 } 1810 ap_reset_promisc(ic); 1811 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1812 /* 1813 * Manual/background scan, don't select+join the 1814 * bss, just return. The scanning framework will 1815 * handle notification that this has completed. 1816 */ 1817 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1818 return 1; 1819 } 1820 ieee80211_create_ibss(vap, 1821 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht)); 1822 return 1; 1823 } 1824 1825 static const struct ieee80211_scanner ap_default = { 1826 .scan_name = "default", 1827 .scan_attach = sta_attach, 1828 .scan_detach = sta_detach, 1829 .scan_start = ap_start, 1830 .scan_restart = sta_restart, 1831 .scan_cancel = ap_cancel, 1832 .scan_end = ap_end, 1833 .scan_flush = sta_flush, 1834 .scan_pickchan = ap_pick_channel, 1835 .scan_add = sta_add, 1836 .scan_age = adhoc_age, 1837 .scan_iterate = sta_iterate, 1838 .scan_assoc_success = sta_assoc_success, 1839 .scan_assoc_fail = sta_assoc_fail, 1840 }; 1841 IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1842 1843 #ifdef IEEE80211_SUPPORT_MESH 1844 /* 1845 * Pick an mbss network to join or find a channel 1846 * to use to start an mbss network. 1847 */ 1848 static int 1849 mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1850 { 1851 struct sta_table *st = ss->ss_priv; 1852 struct ieee80211_mesh_state *ms = vap->iv_mesh; 1853 struct sta_entry *selbs; 1854 struct ieee80211_channel *chan; 1855 1856 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, 1857 ("wrong opmode %u", vap->iv_opmode)); 1858 1859 if (st->st_newscan) { 1860 sta_update_notseen(st); 1861 st->st_newscan = 0; 1862 } 1863 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1864 /* 1865 * Manual/background scan, don't select+join the 1866 * bss, just return. The scanning framework will 1867 * handle notification that this has completed. 1868 */ 1869 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1870 return 1; 1871 } 1872 /* 1873 * Automatic sequencing; look for a candidate and 1874 * if found join the network. 1875 */ 1876 /* NB: unlocked read should be ok */ 1877 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1878 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1879 "%s: no scan candidate\n", __func__); 1880 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1881 return 0; 1882 notfound: 1883 if (ms->ms_idlen != 0) { 1884 /* 1885 * No existing mbss network to join and we have 1886 * a meshid; start one up. If no channel was 1887 * specified, try to select a channel. 1888 */ 1889 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1890 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1891 struct ieee80211com *ic = vap->iv_ic; 1892 1893 chan = adhoc_pick_channel(ss, 0); 1894 if (chan != NULL) 1895 chan = ieee80211_ht_adjust_channel(ic, 1896 chan, vap->iv_flags_ht); 1897 } else 1898 chan = vap->iv_des_chan; 1899 if (chan != NULL) { 1900 ieee80211_create_ibss(vap, chan); 1901 return 1; 1902 } 1903 } 1904 /* 1905 * If nothing suitable was found decrement 1906 * the failure counts so entries will be 1907 * reconsidered the next time around. We 1908 * really want to do this only for sta's 1909 * where we've previously had some success. 1910 */ 1911 sta_dec_fails(st); 1912 st->st_newscan = 1; 1913 return 0; /* restart scan */ 1914 } 1915 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1916 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1917 return (selbs != NULL); 1918 if (selbs == NULL) 1919 goto notfound; 1920 chan = selbs->base.se_chan; 1921 if (selbs->se_flags & STA_DEMOTE11B) 1922 chan = demote11b(vap, chan); 1923 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1924 goto notfound; 1925 return 1; /* terminate scan */ 1926 } 1927 1928 static const struct ieee80211_scanner mesh_default = { 1929 .scan_name = "default", 1930 .scan_attach = sta_attach, 1931 .scan_detach = sta_detach, 1932 .scan_start = adhoc_start, 1933 .scan_restart = sta_restart, 1934 .scan_cancel = sta_cancel, 1935 .scan_end = mesh_pick_bss, 1936 .scan_flush = sta_flush, 1937 .scan_pickchan = adhoc_pick_channel, 1938 .scan_add = sta_add, 1939 .scan_age = adhoc_age, 1940 .scan_iterate = sta_iterate, 1941 .scan_assoc_fail = sta_assoc_fail, 1942 .scan_assoc_success = sta_assoc_success, 1943 }; 1944 IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); 1945 #endif /* IEEE80211_SUPPORT_MESH */ 1946 1947 #if defined(__HAIKU__) 1948 void 1949 ieee80211_scan_sta_init() 1950 { 1951 ieee80211_scanner_register(IEEE80211_M_STA, &sta_default); 1952 ieee80211_scanner_register(IEEE80211_M_IBSS, &adhoc_default); 1953 } 1954 1955 void 1956 ieee80211_scan_sta_uninit() 1957 { 1958 ieee80211_scanner_unregister(IEEE80211_M_STA, &sta_default); 1959 ieee80211_scanner_unregister(IEEE80211_M_IBSS, &adhoc_default); 1960 } 1961 #endif /* __HAIKU__ */ 1962