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