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 * $FreeBSD: head/sys/net80211/ieee80211_scan_sta.c 196005 2009-07-31 19:13:16Z sam $ 26 * $DragonFly$ 27 */ 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 #include <sys/lock.h> 39 40 #include <sys/socket.h> 41 42 #include <net/if.h> 43 #include <net/if_media.h> 44 #include <net/ethernet.h> 45 #include <net/route.h> 46 47 #include <netproto/802_11/ieee80211_var.h> 48 #include <netproto/802_11/ieee80211_input.h> 49 #include <netproto/802_11/ieee80211_regdomain.h> 50 #ifdef IEEE80211_SUPPORT_TDMA 51 #include <netproto/802_11/ieee80211_tdma.h> 52 #endif 53 #ifdef IEEE80211_SUPPORT_MESH 54 #include <netproto/802_11/ieee80211_mesh.h> 55 #endif 56 57 #include <net/bpf.h> 58 59 /* 60 * Parameters for managing cache entries: 61 * 62 * o a station with STA_FAILS_MAX failures is not considered 63 * when picking a candidate 64 * o a station that hasn't had an update in STA_PURGE_SCANS 65 * (background) scans is discarded 66 * o after STA_FAILS_AGE seconds we clear the failure count 67 */ 68 #define STA_FAILS_MAX 2 /* assoc failures before ignored */ 69 #define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ 70 #define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ 71 72 /* XXX tunable */ 73 #define STA_RSSI_MIN 8 /* min acceptable rssi */ 74 #define STA_RSSI_MAX 40 /* max rssi for comparison */ 75 76 struct sta_entry { 77 struct ieee80211_scan_entry base; 78 TAILQ_ENTRY(sta_entry) se_list; 79 LIST_ENTRY(sta_entry) se_hash; 80 uint8_t se_fails; /* failure to associate count */ 81 uint8_t se_seen; /* seen during current scan */ 82 uint8_t se_notseen; /* not seen in previous scans */ 83 uint8_t se_flags; 84 #define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ 85 uint32_t se_avgrssi; /* LPF rssi state */ 86 unsigned long se_lastupdate; /* time of last update */ 87 unsigned long se_lastfail; /* time of last failure */ 88 unsigned long se_lastassoc; /* time of last association */ 89 u_int se_scangen; /* iterator scan gen# */ 90 u_int se_countrygen; /* gen# of last cc notify */ 91 }; 92 93 #define STA_HASHSIZE 32 94 /* simple hash is enough for variation of macaddr */ 95 #define STA_HASH(addr) \ 96 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) 97 98 #define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */ 99 CTASSERT(MAX_IEEE_CHAN >= 256); 100 101 struct sta_table { 102 struct lock st_lock; /* on scan table */ 103 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 104 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 105 struct lock st_scanlock; /* on st_scaniter */ 106 u_int st_scaniter; /* gen# for iterator */ 107 u_int st_scangen; /* scan generation # */ 108 int st_newscan; 109 /* ap-related state */ 110 int st_maxrssi[MAX_IEEE_CHAN]; 111 }; 112 113 static void sta_flush_table(struct sta_table *); 114 /* 115 * match_bss returns a bitmask describing if an entry is suitable 116 * for use. If non-zero the entry was deemed not suitable and it's 117 * contents explains why. The following flags are or'd to to this 118 * mask and can be used to figure out why the entry was rejected. 119 */ 120 #define MATCH_CHANNEL 0x00001 /* channel mismatch */ 121 #define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ 122 #define MATCH_PRIVACY 0x00004 /* privacy mismatch */ 123 #define MATCH_RATE 0x00008 /* rate set mismatch */ 124 #define MATCH_SSID 0x00010 /* ssid mismatch */ 125 #define MATCH_BSSID 0x00020 /* bssid mismatch */ 126 #define MATCH_FAILS 0x00040 /* too many failed auth attempts */ 127 #define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ 128 #define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ 129 #define MATCH_CC 0x00200 /* country code mismatch */ 130 #define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ 131 #define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ 132 #define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ 133 #define MATCH_TDMA_LOCAL 0x02000 /* local address */ 134 #define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ 135 #define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ 136 #define MATCH_MESHID 0x20000 /* meshid mismatch */ 137 static int match_bss(struct ieee80211vap *, 138 const struct ieee80211_scan_state *, struct sta_entry *, int); 139 static void adhoc_age(struct ieee80211_scan_state *); 140 141 static __inline int 142 isocmp(const uint8_t cc1[], const uint8_t cc2[]) 143 { 144 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 145 } 146 147 /* number of references from net80211 layer */ 148 static int nrefs = 0; 149 /* 150 * Module glue. 151 */ 152 IEEE80211_SCANNER_MODULE(sta, 1); 153 154 /* 155 * Attach prior to any scanning work. 156 */ 157 static int 158 sta_attach(struct ieee80211_scan_state *ss) 159 { 160 struct sta_table *st; 161 162 st = (struct sta_table *) kmalloc(sizeof(struct sta_table), 163 M_80211_SCAN, M_INTWAIT | M_ZERO); 164 if (st == NULL) 165 return 0; 166 lockinit(&st->st_lock, "scantable", 0, 0); 167 lockinit(&st->st_scanlock, "scangen", 0, 0); 168 TAILQ_INIT(&st->st_entry); 169 ss->ss_priv = st; 170 nrefs++; /* NB: we assume caller locking */ 171 return 1; 172 } 173 174 /* 175 * Cleanup any private state. 176 */ 177 static int 178 sta_detach(struct ieee80211_scan_state *ss) 179 { 180 struct sta_table *st = ss->ss_priv; 181 182 if (st != NULL) { 183 sta_flush_table(st); 184 lockuninit(&st->st_lock); 185 lockuninit(&st->st_scanlock); 186 kfree(st, M_80211_SCAN); 187 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 188 nrefs--; /* NB: we assume caller locking */ 189 } 190 return 1; 191 } 192 193 /* 194 * Flush all per-scan state. 195 */ 196 static int 197 sta_flush(struct ieee80211_scan_state *ss) 198 { 199 struct sta_table *st = ss->ss_priv; 200 201 lockmgr(&st->st_lock, LK_EXCLUSIVE); 202 sta_flush_table(st); 203 lockmgr(&st->st_lock, LK_RELEASE); 204 ss->ss_last = 0; 205 return 0; 206 } 207 208 /* 209 * Flush all entries in the scan cache. 210 */ 211 static void 212 sta_flush_table(struct sta_table *st) 213 { 214 struct sta_entry *se, *next; 215 216 TAILQ_FOREACH_MUTABLE(se, &st->st_entry, se_list, next) { 217 TAILQ_REMOVE(&st->st_entry, se, se_list); 218 LIST_REMOVE(se, se_hash); 219 ieee80211_ies_cleanup(&se->base.se_ies); 220 kfree(se, M_80211_SCAN); 221 } 222 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 223 } 224 225 /* 226 * Process a beacon or probe response frame; create an 227 * entry in the scan cache or update any previous entry. 228 */ 229 static int 230 sta_add(struct ieee80211_scan_state *ss, 231 const struct ieee80211_scanparams *sp, 232 const struct ieee80211_frame *wh, 233 int subtype, int rssi, int noise) 234 { 235 #define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 236 #define PICK1ST(_ss) \ 237 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 238 IEEE80211_SCAN_PICK1ST) 239 struct sta_table *st = ss->ss_priv; 240 const uint8_t *macaddr = wh->i_addr2; 241 struct ieee80211vap *vap = ss->ss_vap; 242 struct ieee80211com *ic = vap->iv_ic; 243 struct sta_entry *se; 244 struct ieee80211_scan_entry *ise; 245 int hash; 246 247 hash = STA_HASH(macaddr); 248 249 lockmgr(&st->st_lock, LK_EXCLUSIVE); 250 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 251 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 252 goto found; 253 se = (struct sta_entry *) kmalloc(sizeof(struct sta_entry), 254 M_80211_SCAN, M_INTWAIT | M_ZERO); 255 if (se == NULL) { 256 lockmgr(&st->st_lock, LK_RELEASE); 257 return 0; 258 } 259 se->se_scangen = st->st_scaniter-1; 260 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 261 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 262 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 263 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 264 found: 265 ise = &se->base; 266 /* XXX ap beaconing multiple ssid w/ same bssid */ 267 if (sp->ssid[1] != 0 && 268 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 269 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 270 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 271 ("rate set too large: %u", sp->rates[1])); 272 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 273 if (sp->xrates != NULL) { 274 /* XXX validate xrates[1] */ 275 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 276 ("xrate set too large: %u", sp->xrates[1])); 277 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 278 } else 279 ise->se_xrates[1] = 0; 280 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 281 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 282 /* 283 * Record rssi data using extended precision LPF filter. 284 * 285 * NB: use only on-channel data to insure we get a good 286 * estimate of the signal we'll see when associated. 287 */ 288 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 289 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 290 ise->se_noise = noise; 291 } 292 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 293 ise->se_intval = sp->bintval; 294 ise->se_capinfo = sp->capinfo; 295 #ifdef IEEE80211_SUPPORT_MESH 296 if (sp->meshid != NULL && sp->meshid[1] != 0) 297 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); 298 #endif 299 /* 300 * Beware of overriding se_chan for frames seen 301 * off-channel; this can cause us to attempt an 302 * association on the wrong channel. 303 */ 304 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 305 struct ieee80211_channel *c; 306 /* 307 * Off-channel, locate the home/bss channel for the sta 308 * using the value broadcast in the DSPARMS ie. We know 309 * sp->chan has this value because it's used to calculate 310 * IEEE80211_BPARSE_OFFCHAN. 311 */ 312 c = ieee80211_find_channel_byieee(ic, sp->chan, 313 ic->ic_curchan->ic_flags); 314 if (c != NULL) { 315 ise->se_chan = c; 316 } else if (ise->se_chan == NULL) { 317 /* should not happen, pick something */ 318 ise->se_chan = ic->ic_curchan; 319 } 320 } else 321 ise->se_chan = ic->ic_curchan; 322 ise->se_fhdwell = sp->fhdwell; 323 ise->se_fhindex = sp->fhindex; 324 ise->se_erp = sp->erp; 325 ise->se_timoff = sp->timoff; 326 if (sp->tim != NULL) { 327 const struct ieee80211_tim_ie *tim = 328 (const struct ieee80211_tim_ie *) sp->tim; 329 ise->se_dtimperiod = tim->tim_period; 330 } 331 if (sp->country != NULL) { 332 const struct ieee80211_country_ie *cie = 333 (const struct ieee80211_country_ie *) sp->country; 334 /* 335 * If 11d is enabled and we're attempting to join a bss 336 * that advertises it's country code then compare our 337 * current settings to what we fetched from the country ie. 338 * If our country code is unspecified or different then 339 * dispatch an event to user space that identifies the 340 * country code so our regdomain config can be changed. 341 */ 342 /* XXX only for STA mode? */ 343 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 344 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 345 (ic->ic_regdomain.country == CTRY_DEFAULT || 346 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 347 /* only issue one notify event per scan */ 348 if (se->se_countrygen != st->st_scangen) { 349 ieee80211_notify_country(vap, ise->se_bssid, 350 cie->cc); 351 se->se_countrygen = st->st_scangen; 352 } 353 } 354 ise->se_cc[0] = cie->cc[0]; 355 ise->se_cc[1] = cie->cc[1]; 356 } 357 /* NB: no need to setup ie ptrs; they are not (currently) used */ 358 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 359 360 /* clear failure count after STA_FAIL_AGE passes */ 361 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 362 se->se_fails = 0; 363 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 364 "%s: fails %u", __func__, se->se_fails); 365 } 366 367 se->se_lastupdate = ticks; /* update time */ 368 se->se_seen = 1; 369 se->se_notseen = 0; 370 371 KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); 372 if (rssi > st->st_maxrssi[sp->bchan]) 373 st->st_maxrssi[sp->bchan] = rssi; 374 375 lockmgr(&st->st_lock, LK_RELEASE); 376 377 /* 378 * If looking for a quick choice and nothing's 379 * been found check here. 380 */ 381 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 382 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 383 384 return 1; 385 #undef PICK1ST 386 #undef ISPROBE 387 } 388 389 /* 390 * Check if a channel is excluded by user request. 391 */ 392 static int 393 isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 394 { 395 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 396 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 397 c->ic_freq != vap->iv_des_chan->ic_freq)); 398 } 399 400 static struct ieee80211_channel * 401 find11gchannel(struct ieee80211com *ic, int i, int freq) 402 { 403 struct ieee80211_channel *c; 404 int j; 405 406 /* 407 * The normal ordering in the channel list is b channel 408 * immediately followed by g so optimize the search for 409 * this. We'll still do a full search just in case. 410 */ 411 for (j = i+1; j < ic->ic_nchans; j++) { 412 c = &ic->ic_channels[j]; 413 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 414 return c; 415 } 416 for (j = 0; j < i; j++) { 417 c = &ic->ic_channels[j]; 418 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 419 return c; 420 } 421 return NULL; 422 } 423 424 static const u_int chanflags[IEEE80211_MODE_MAX] = { 425 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, 426 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, 427 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, 428 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, 429 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, 430 /* check base channel */ 431 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, 432 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, 433 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, 434 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, 435 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, 436 /* check legacy */ 437 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, 438 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, 439 }; 440 441 static void 442 add_channels(struct ieee80211vap *vap, 443 struct ieee80211_scan_state *ss, 444 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 445 { 446 #define N(a) (sizeof(a) / sizeof(a[0])) 447 struct ieee80211com *ic = vap->iv_ic; 448 struct ieee80211_channel *c, *cg; 449 u_int modeflags; 450 int i; 451 452 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode)); 453 modeflags = chanflags[mode]; 454 for (i = 0; i < nfreq; i++) { 455 if (ss->ss_last >= IEEE80211_SCAN_MAX) 456 break; 457 458 c = ieee80211_find_channel(ic, freq[i], modeflags); 459 if (c == NULL || isexcluded(vap, c)) 460 continue; 461 if (mode == IEEE80211_MODE_AUTO) { 462 /* 463 * XXX special-case 11b/g channels so we select 464 * the g channel if both are present. 465 */ 466 if (IEEE80211_IS_CHAN_B(c) && 467 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 468 c = cg; 469 } 470 ss->ss_chans[ss->ss_last++] = c; 471 } 472 #undef N 473 } 474 475 struct scanlist { 476 uint16_t mode; 477 uint16_t count; 478 const uint16_t *list; 479 }; 480 481 static int 482 checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 483 { 484 int i; 485 486 for (; scan->list != NULL; scan++) { 487 for (i = 0; i < scan->count; i++) 488 if (scan->list[i] == c->ic_freq) 489 return 1; 490 } 491 return 0; 492 } 493 494 static int 495 onscanlist(const struct ieee80211_scan_state *ss, 496 const struct ieee80211_channel *c) 497 { 498 int i; 499 500 for (i = 0; i < ss->ss_last; i++) 501 if (ss->ss_chans[i] == c) 502 return 1; 503 return 0; 504 } 505 506 static void 507 sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 508 const struct scanlist table[]) 509 { 510 struct ieee80211com *ic = vap->iv_ic; 511 struct ieee80211_channel *c; 512 int i; 513 514 for (i = 0; i < ic->ic_nchans; i++) { 515 if (ss->ss_last >= IEEE80211_SCAN_MAX) 516 break; 517 518 c = &ic->ic_channels[i]; 519 /* 520 * Ignore dynamic turbo channels; we scan them 521 * in normal mode (i.e. not boosted). Likewise 522 * for HT channels, they get scanned using 523 * legacy rates. 524 */ 525 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) 526 continue; 527 528 /* 529 * If a desired mode was specified, scan only 530 * channels that satisfy that constraint. 531 */ 532 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 533 vap->iv_des_mode != ieee80211_chan2mode(c)) 534 continue; 535 536 /* 537 * Skip channels excluded by user request. 538 */ 539 if (isexcluded(vap, c)) 540 continue; 541 542 /* 543 * Add the channel unless it is listed in the 544 * fixed scan order tables. This insures we 545 * don't sweep back in channels we filtered out 546 * above. 547 */ 548 if (checktable(table, c)) 549 continue; 550 551 /* Add channel to scanning list. */ 552 ss->ss_chans[ss->ss_last++] = c; 553 } 554 /* 555 * Explicitly add any desired channel if: 556 * - not already on the scan list 557 * - allowed by any desired mode constraint 558 * - there is space in the scan list 559 * This allows the channel to be used when the filtering 560 * mechanisms would otherwise elide it (e.g HT, turbo). 561 */ 562 c = vap->iv_des_chan; 563 if (c != IEEE80211_CHAN_ANYC && 564 !onscanlist(ss, c) && 565 (vap->iv_des_mode == IEEE80211_MODE_AUTO || 566 vap->iv_des_mode == ieee80211_chan2mode(c)) && 567 ss->ss_last < IEEE80211_SCAN_MAX) 568 ss->ss_chans[ss->ss_last++] = c; 569 } 570 571 static void 572 makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 573 const struct scanlist table[]) 574 { 575 const struct scanlist *scan; 576 enum ieee80211_phymode mode; 577 578 ss->ss_last = 0; 579 /* 580 * Use the table of ordered channels to construct the list 581 * of channels for scanning. Any channels in the ordered 582 * list not in the master list will be discarded. 583 */ 584 for (scan = table; scan->list != NULL; scan++) { 585 mode = scan->mode; 586 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { 587 /* 588 * If a desired mode was specified, scan only 589 * channels that satisfy that constraint. 590 */ 591 if (vap->iv_des_mode != mode) { 592 /* 593 * The scan table marks 2.4Ghz channels as b 594 * so if the desired mode is 11g, then use 595 * the 11b channel list but upgrade the mode. 596 */ 597 if (vap->iv_des_mode != IEEE80211_MODE_11G || 598 mode != IEEE80211_MODE_11B) 599 continue; 600 mode = IEEE80211_MODE_11G; /* upgrade */ 601 } 602 } else { 603 /* 604 * This lets add_channels upgrade an 11b channel 605 * to 11g if available. 606 */ 607 if (mode == IEEE80211_MODE_11B) 608 mode = IEEE80211_MODE_AUTO; 609 } 610 #ifdef IEEE80211_F_XR 611 /* XR does not operate on turbo channels */ 612 if ((vap->iv_flags & IEEE80211_F_XR) && 613 (mode == IEEE80211_MODE_TURBO_A || 614 mode == IEEE80211_MODE_TURBO_G || 615 mode == IEEE80211_MODE_STURBO_A)) 616 continue; 617 #endif 618 /* 619 * Add the list of the channels; any that are not 620 * in the master channel list will be discarded. 621 */ 622 add_channels(vap, ss, mode, scan->list, scan->count); 623 } 624 625 /* 626 * Add the channels from the ic that are not present 627 * in the table. 628 */ 629 sweepchannels(ss, vap, table); 630 } 631 632 static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 633 { 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 634 static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 635 { 5170, 5190, 5210, 5230 }; 636 static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 637 { 2412, 2437, 2462, 2442, 2472 }; 638 static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 639 { 5745, 5765, 5785, 5805, 5825 }; 640 static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 641 { 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 642 static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 643 { 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 644 static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 645 { 2484 }; 646 static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 647 { 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 648 static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 649 { 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 650 #ifdef ATH_TURBO_SCAN 651 static const uint16_t rcl5[] = /* 3 static turbo channels */ 652 { 5210, 5250, 5290 }; 653 static const uint16_t rcl6[] = /* 2 static turbo channels */ 654 { 5760, 5800 }; 655 static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 656 { 5540, 5580, 5620, 5660 }; 657 static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 658 { 2437 }; 659 static const uint16_t rcl13[] = /* dynamic Turbo channels */ 660 { 5200, 5240, 5280, 5765, 5805 }; 661 #endif /* ATH_TURBO_SCAN */ 662 663 #define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 664 665 static const struct scanlist staScanTable[] = { 666 { IEEE80211_MODE_11B, X(rcl3) }, 667 { IEEE80211_MODE_11A, X(rcl1) }, 668 { IEEE80211_MODE_11A, X(rcl2) }, 669 { IEEE80211_MODE_11B, X(rcl8) }, 670 { IEEE80211_MODE_11B, X(rcl9) }, 671 { IEEE80211_MODE_11A, X(rcl4) }, 672 #ifdef ATH_TURBO_SCAN 673 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 674 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 675 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 676 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 677 #endif /* ATH_TURBO_SCAN */ 678 { IEEE80211_MODE_11A, X(rcl7) }, 679 { IEEE80211_MODE_11B, X(rcl10) }, 680 { IEEE80211_MODE_11A, X(rcl11) }, 681 #ifdef ATH_TURBO_SCAN 682 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 683 #endif /* ATH_TURBO_SCAN */ 684 { .list = NULL } 685 }; 686 687 /* 688 * Start a station-mode scan by populating the channel list. 689 */ 690 static int 691 sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 692 { 693 struct sta_table *st = ss->ss_priv; 694 695 makescanlist(ss, vap, staScanTable); 696 697 if (ss->ss_mindwell == 0) 698 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 699 if (ss->ss_maxdwell == 0) 700 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 701 702 st->st_scangen++; 703 st->st_newscan = 1; 704 705 return 0; 706 } 707 708 /* 709 * Restart a scan, typically a bg scan but can 710 * also be a fg scan that came up empty. 711 */ 712 static int 713 sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 714 { 715 struct sta_table *st = ss->ss_priv; 716 717 st->st_newscan = 1; 718 return 0; 719 } 720 721 /* 722 * Cancel an ongoing scan. 723 */ 724 static int 725 sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 726 { 727 return 0; 728 } 729 730 /* unalligned little endian access */ 731 #define LE_READ_2(p) \ 732 ((uint16_t) \ 733 ((((const uint8_t *)(p))[0] ) | \ 734 (((const uint8_t *)(p))[1] << 8))) 735 736 /* 737 * Demote any supplied 11g channel to 11b. There should 738 * always be an 11b channel but we check anyway... 739 */ 740 static struct ieee80211_channel * 741 demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 742 { 743 struct ieee80211_channel *c; 744 745 if (IEEE80211_IS_CHAN_ANYG(chan) && 746 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 747 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 748 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 749 IEEE80211_CHAN_B); 750 if (c != NULL) 751 chan = c; 752 } 753 return chan; 754 } 755 756 static int 757 maxrate(const struct ieee80211_scan_entry *se) 758 { 759 const struct ieee80211_ie_htcap *htcap = 760 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 761 int rmax, r, i; 762 uint16_t caps; 763 764 rmax = 0; 765 if (htcap != NULL) { 766 /* 767 * HT station; inspect supported MCS and then adjust 768 * rate by channel width. Could also include short GI 769 * in this if we want to be extra accurate. 770 */ 771 /* XXX assumes MCS15 is max */ 772 for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--) 773 ; 774 if (i >= 0) { 775 caps = LE_READ_2(&htcap->hc_cap); 776 /* XXX short/long GI */ 777 if (caps & IEEE80211_HTCAP_CHWIDTH40) 778 rmax = ieee80211_htrates[i].ht40_rate_400ns; 779 else 780 rmax = ieee80211_htrates[i].ht40_rate_800ns; 781 } 782 } 783 for (i = 0; i < se->se_rates[1]; i++) { 784 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 785 if (r > rmax) 786 rmax = r; 787 } 788 for (i = 0; i < se->se_xrates[1]; i++) { 789 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 790 if (r > rmax) 791 rmax = r; 792 } 793 return rmax; 794 } 795 796 /* 797 * Compare the capabilities of two entries and decide which is 798 * more desirable (return >0 if a is considered better). Note 799 * that we assume compatibility/usability has already been checked 800 * so we don't need to (e.g. validate whether privacy is supported). 801 * Used to select the best scan candidate for association in a BSS. 802 */ 803 static int 804 sta_compare(const struct sta_entry *a, const struct sta_entry *b) 805 { 806 #define PREFER(_a,_b,_what) do { \ 807 if (((_a) ^ (_b)) & (_what)) \ 808 return ((_a) & (_what)) ? 1 : -1; \ 809 } while (0) 810 #define ABS(_a) ((_a) < 0 ? -(_a) : (_a)) 811 int maxa, maxb; 812 int8_t rssia, rssib; 813 int weight; 814 815 /* privacy support */ 816 PREFER(a->base.se_capinfo, b->base.se_capinfo, 817 IEEE80211_CAPINFO_PRIVACY); 818 819 /* compare count of previous failures */ 820 weight = b->se_fails - a->se_fails; 821 if (ABS(weight) > 1) 822 return weight; 823 824 /* 825 * Compare rssi. If the two are considered equivalent 826 * then fallback to other criteria. We threshold the 827 * comparisons to avoid selecting an ap purely by rssi 828 * when both values may be good but one ap is otherwise 829 * more desirable (e.g. an 11b-only ap with stronger 830 * signal than an 11g ap). 831 */ 832 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 833 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 834 if (ABS(rssib - rssia) < 5) { 835 /* best/max rate preferred if signal level close enough XXX */ 836 maxa = maxrate(&a->base); 837 maxb = maxrate(&b->base); 838 if (maxa != maxb) 839 return maxa - maxb; 840 /* XXX use freq for channel preference */ 841 /* for now just prefer 5Ghz band to all other bands */ 842 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 843 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 844 } 845 /* all things being equal, use signal level */ 846 return a->base.se_rssi - b->base.se_rssi; 847 #undef PREFER 848 #undef ABS 849 } 850 851 /* 852 * Check rate set suitability and return the best supported rate. 853 * XXX inspect MCS for HT 854 */ 855 static int 856 check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 857 const struct ieee80211_scan_entry *se) 858 { 859 #define RV(v) ((v) & IEEE80211_RATE_VAL) 860 const struct ieee80211_rateset *srs; 861 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 862 const uint8_t *rs; 863 864 okrate = badrate = 0; 865 866 srs = ieee80211_get_suprates(vap->iv_ic, chan); 867 nrs = se->se_rates[1]; 868 rs = se->se_rates+2; 869 /* XXX MCS */ 870 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 871 fixedrate = IEEE80211_FIXED_RATE_NONE; 872 again: 873 for (i = 0; i < nrs; i++) { 874 r = RV(rs[i]); 875 badrate = r; 876 /* 877 * Check any fixed rate is included. 878 */ 879 if (r == ucastrate) 880 fixedrate = r; 881 /* 882 * Check against our supported rates. 883 */ 884 for (j = 0; j < srs->rs_nrates; j++) 885 if (r == RV(srs->rs_rates[j])) { 886 if (r > okrate) /* NB: track max */ 887 okrate = r; 888 break; 889 } 890 891 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 892 /* 893 * Don't try joining a BSS, if we don't support 894 * one of its basic rates. 895 */ 896 okrate = 0; 897 goto back; 898 } 899 } 900 if (rs == se->se_rates+2) { 901 /* scan xrates too; sort of an algol68-style for loop */ 902 nrs = se->se_xrates[1]; 903 rs = se->se_xrates+2; 904 goto again; 905 } 906 907 back: 908 if (okrate == 0 || ucastrate != fixedrate) 909 return badrate | IEEE80211_RATE_BASIC; 910 else 911 return RV(okrate); 912 #undef RV 913 } 914 915 static __inline int 916 match_id(const uint8_t *ie, const uint8_t *val, int len) 917 { 918 return (ie[1] == len && memcmp(ie+2, val, len) == 0); 919 } 920 921 static int 922 match_ssid(const uint8_t *ie, 923 int nssid, const struct ieee80211_scan_ssid ssids[]) 924 { 925 int i; 926 927 for (i = 0; i < nssid; i++) { 928 if (match_id(ie, ssids[i].ssid, ssids[i].len)) 929 return 1; 930 } 931 return 0; 932 } 933 934 #ifdef IEEE80211_SUPPORT_TDMA 935 static int 936 tdma_isfull(const struct ieee80211_tdma_param *tdma) 937 { 938 int slot, slotcnt; 939 940 slotcnt = tdma->tdma_slotcnt; 941 for (slot = slotcnt-1; slot >= 0; slot--) 942 if (isclr(tdma->tdma_inuse, slot)) 943 return 0; 944 return 1; 945 } 946 #endif /* IEEE80211_SUPPORT_TDMA */ 947 948 /* 949 * Test a scan candidate for suitability/compatibility. 950 */ 951 static int 952 match_bss(struct ieee80211vap *vap, 953 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 954 int debug) 955 { 956 struct ieee80211com *ic = vap->iv_ic; 957 struct ieee80211_scan_entry *se = &se0->base; 958 uint8_t rate; 959 int fail; 960 961 fail = 0; 962 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 963 fail |= MATCH_CHANNEL; 964 /* 965 * NB: normally the desired mode is used to construct 966 * the channel list, but it's possible for the scan 967 * cache to include entries for stations outside this 968 * list so we check the desired mode here to weed them 969 * out. 970 */ 971 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 972 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 973 chanflags[vap->iv_des_mode]) 974 fail |= MATCH_CHANNEL; 975 if (vap->iv_opmode == IEEE80211_M_IBSS) { 976 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 977 fail |= MATCH_CAPINFO; 978 #ifdef IEEE80211_SUPPORT_TDMA 979 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { 980 /* 981 * Adhoc demo network setup shouldn't really be scanning 982 * but just in case skip stations operating in IBSS or 983 * BSS mode. 984 */ 985 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 986 fail |= MATCH_CAPINFO; 987 /* 988 * TDMA operation cannot coexist with a normal 802.11 network; 989 * skip if IBSS or ESS capabilities are marked and require 990 * the beacon have a TDMA ie present. 991 */ 992 if (vap->iv_caps & IEEE80211_C_TDMA) { 993 const struct ieee80211_tdma_param *tdma = 994 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; 995 const struct ieee80211_tdma_state *ts = vap->iv_tdma; 996 997 if (tdma == NULL) 998 fail |= MATCH_TDMA_NOIE; 999 else if (tdma->tdma_version != ts->tdma_version) 1000 fail |= MATCH_TDMA_VERSION; 1001 else if (tdma->tdma_slot != 0) 1002 fail |= MATCH_TDMA_NOTMASTER; 1003 else if (tdma_isfull(tdma)) 1004 fail |= MATCH_TDMA_NOSLOT; 1005 #if 0 1006 else if (ieee80211_local_address(se->se_macaddr)) 1007 fail |= MATCH_TDMA_LOCAL; 1008 #endif 1009 } 1010 #endif /* IEEE80211_SUPPORT_TDMA */ 1011 #ifdef IEEE80211_SUPPORT_MESH 1012 } else if (vap->iv_opmode == IEEE80211_M_MBSS) { 1013 const struct ieee80211_mesh_state *ms = vap->iv_mesh; 1014 /* 1015 * Mesh nodes have IBSS & ESS bits in capinfo turned off 1016 * and two special ie's that must be present. 1017 */ 1018 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1019 fail |= MATCH_CAPINFO; 1020 else if (&se->se_meshid == NULL) 1021 fail |= MATCH_MESH_NOID; 1022 else if (ms->ms_idlen != 0 && 1023 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) 1024 fail |= MATCH_MESHID; 1025 #endif 1026 } else { 1027 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 1028 fail |= MATCH_CAPINFO; 1029 /* 1030 * If 11d is enabled and we're attempting to join a bss 1031 * that advertises it's country code then compare our 1032 * current settings to what we fetched from the country ie. 1033 * If our country code is unspecified or different then do 1034 * not attempt to join the bss. We should have already 1035 * dispatched an event to user space that identifies the 1036 * new country code so our regdomain config should match. 1037 */ 1038 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 1039 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 1040 se->se_cc[0] != 0 && 1041 (ic->ic_regdomain.country == CTRY_DEFAULT || 1042 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 1043 fail |= MATCH_CC; 1044 } 1045 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 1046 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 1047 fail |= MATCH_PRIVACY; 1048 } else { 1049 /* XXX does this mean privacy is supported or required? */ 1050 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 1051 fail |= MATCH_PRIVACY; 1052 } 1053 se0->se_flags &= ~STA_DEMOTE11B; 1054 rate = check_rate(vap, se->se_chan, se); 1055 if (rate & IEEE80211_RATE_BASIC) { 1056 fail |= MATCH_RATE; 1057 /* 1058 * An 11b-only ap will give a rate mismatch if there is an 1059 * OFDM fixed tx rate for 11g. Try downgrading the channel 1060 * in the scan list to 11b and retry the rate check. 1061 */ 1062 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 1063 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 1064 if ((rate & IEEE80211_RATE_BASIC) == 0) { 1065 fail &= ~MATCH_RATE; 1066 se0->se_flags |= STA_DEMOTE11B; 1067 } 1068 } 1069 } else if (rate < 2*24) { 1070 /* 1071 * This is an 11b-only ap. Check the desired mode in 1072 * case that needs to be honored (mode 11g filters out 1073 * 11b-only ap's). Otherwise force any 11g channel used 1074 * in scanning to be demoted. 1075 * 1076 * NB: we cheat a bit here by looking at the max rate; 1077 * we could/should check the rates. 1078 */ 1079 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 1080 vap->iv_des_mode == IEEE80211_MODE_11B)) 1081 fail |= MATCH_RATE; 1082 else 1083 se0->se_flags |= STA_DEMOTE11B; 1084 } 1085 if (ss->ss_nssid != 0 && 1086 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 1087 fail |= MATCH_SSID; 1088 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 1089 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 1090 fail |= MATCH_BSSID; 1091 if (se0->se_fails >= STA_FAILS_MAX) 1092 fail |= MATCH_FAILS; 1093 if (se0->se_notseen >= STA_PURGE_SCANS) 1094 fail |= MATCH_NOTSEEN; 1095 if (se->se_rssi < STA_RSSI_MIN) 1096 fail |= MATCH_RSSI; 1097 #ifdef IEEE80211_DEBUG 1098 if (ieee80211_msg(vap, debug)) { 1099 kprintf(" %c %6D", 1100 fail & MATCH_FAILS ? '=' : 1101 fail & MATCH_NOTSEEN ? '^' : 1102 fail & MATCH_CC ? '$' : 1103 #ifdef IEEE80211_SUPPORT_TDMA 1104 fail & MATCH_TDMA_NOIE ? '&' : 1105 fail & MATCH_TDMA_VERSION ? 'v' : 1106 fail & MATCH_TDMA_NOTMASTER ? 's' : 1107 fail & MATCH_TDMA_NOSLOT ? 'f' : 1108 fail & MATCH_TDMA_LOCAL ? 'l' : 1109 #endif 1110 fail & MATCH_MESH_NOID ? 'm' : 1111 fail ? '-' : '+', se->se_macaddr, ":"); 1112 kprintf(" %6D%c", se->se_bssid, ":", 1113 fail & MATCH_BSSID ? '!' : ' '); 1114 kprintf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 1115 fail & MATCH_CHANNEL ? '!' : ' '); 1116 kprintf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 1117 kprintf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 1118 fail & MATCH_RATE ? '!' : ' '); 1119 kprintf(" %4s%c", 1120 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 1121 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", 1122 fail & MATCH_CAPINFO ? '!' : ' '); 1123 kprintf(" %3s%c ", 1124 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 1125 "wep" : "no", 1126 fail & MATCH_PRIVACY ? '!' : ' '); 1127 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 1128 kprintf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); 1129 } 1130 #endif 1131 return fail; 1132 } 1133 1134 static void 1135 sta_update_notseen(struct sta_table *st) 1136 { 1137 struct sta_entry *se; 1138 1139 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1140 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1141 /* 1142 * If seen the reset and don't bump the count; 1143 * otherwise bump the ``not seen'' count. Note 1144 * that this insures that stations for which we 1145 * see frames while not scanning but not during 1146 * this scan will not be penalized. 1147 */ 1148 if (se->se_seen) 1149 se->se_seen = 0; 1150 else 1151 se->se_notseen++; 1152 } 1153 lockmgr(&st->st_lock, LK_RELEASE); 1154 } 1155 1156 static void 1157 sta_dec_fails(struct sta_table *st) 1158 { 1159 struct sta_entry *se; 1160 1161 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1162 TAILQ_FOREACH(se, &st->st_entry, se_list) 1163 if (se->se_fails) 1164 se->se_fails--; 1165 lockmgr(&st->st_lock, LK_RELEASE); 1166 } 1167 1168 static struct sta_entry * 1169 select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1170 { 1171 struct sta_table *st = ss->ss_priv; 1172 struct sta_entry *se, *selbs = NULL; 1173 1174 IEEE80211_DPRINTF(vap, debug, " %s\n", 1175 "macaddr bssid chan rssi rate flag wep essid"); 1176 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1177 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1178 ieee80211_ies_expand(&se->base.se_ies); 1179 if (match_bss(vap, ss, se, debug) == 0) { 1180 if (selbs == NULL) 1181 selbs = se; 1182 else if (sta_compare(se, selbs) > 0) 1183 selbs = se; 1184 } 1185 } 1186 lockmgr(&st->st_lock, LK_RELEASE); 1187 1188 return selbs; 1189 } 1190 1191 /* 1192 * Pick an ap or ibss network to join or find a channel 1193 * to use to start an ibss network. 1194 */ 1195 static int 1196 sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1197 { 1198 struct sta_table *st = ss->ss_priv; 1199 struct sta_entry *selbs; 1200 struct ieee80211_channel *chan; 1201 1202 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1203 ("wrong mode %u", vap->iv_opmode)); 1204 1205 if (st->st_newscan) { 1206 sta_update_notseen(st); 1207 st->st_newscan = 0; 1208 } 1209 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1210 /* 1211 * Manual/background scan, don't select+join the 1212 * bss, just return. The scanning framework will 1213 * handle notification that this has completed. 1214 */ 1215 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1216 return 1; 1217 } 1218 /* 1219 * Automatic sequencing; look for a candidate and 1220 * if found join the network. 1221 */ 1222 /* NB: unlocked read should be ok */ 1223 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1224 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1225 "%s: no scan candidate\n", __func__); 1226 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1227 return 0; 1228 notfound: 1229 /* 1230 * If nothing suitable was found decrement 1231 * the failure counts so entries will be 1232 * reconsidered the next time around. We 1233 * really want to do this only for sta's 1234 * where we've previously had some success. 1235 */ 1236 sta_dec_fails(st); 1237 st->st_newscan = 1; 1238 return 0; /* restart scan */ 1239 } 1240 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1241 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1242 return (selbs != NULL); 1243 if (selbs == NULL) 1244 goto notfound; 1245 chan = selbs->base.se_chan; 1246 if (selbs->se_flags & STA_DEMOTE11B) 1247 chan = demote11b(vap, chan); 1248 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1249 goto notfound; 1250 return 1; /* terminate scan */ 1251 } 1252 1253 /* 1254 * Lookup an entry in the scan cache. We assume we're 1255 * called from the bottom half or such that we don't need 1256 * to block the bottom half so that it's safe to return 1257 * a reference to an entry w/o holding the lock on the table. 1258 */ 1259 static struct sta_entry * 1260 sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1261 { 1262 struct sta_entry *se; 1263 int hash = STA_HASH(macaddr); 1264 1265 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1266 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1267 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1268 break; 1269 lockmgr(&st->st_lock, LK_RELEASE); 1270 1271 return se; /* NB: unlocked */ 1272 } 1273 1274 static void 1275 sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1276 { 1277 struct ieee80211com *ic = vap->iv_ic; 1278 struct ieee80211_node *ni = vap->iv_bss; 1279 struct sta_table *st = ss->ss_priv; 1280 enum ieee80211_phymode mode; 1281 struct sta_entry *se, *selbs; 1282 uint8_t roamRate, curRate, ucastRate; 1283 int8_t roamRssi, curRssi; 1284 1285 se = sta_lookup(st, ni->ni_macaddr); 1286 if (se == NULL) { 1287 /* XXX something is wrong */ 1288 return; 1289 } 1290 1291 mode = ieee80211_chan2mode(ic->ic_bsschan); 1292 roamRate = vap->iv_roamparms[mode].rate; 1293 roamRssi = vap->iv_roamparms[mode].rssi; 1294 ucastRate = vap->iv_txparms[mode].ucastrate; 1295 /* NB: the most up to date rssi is in the node, not the scan cache */ 1296 curRssi = ic->ic_node_getrssi(ni); 1297 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1298 curRate = ni->ni_txrate; 1299 roamRate &= IEEE80211_RATE_VAL; 1300 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1301 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1302 __func__, curRssi, curRate, roamRssi, roamRate); 1303 } else { 1304 curRate = roamRate; /* NB: insure compare below fails */ 1305 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1306 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1307 } 1308 /* 1309 * Check if a new ap should be used and switch. 1310 * XXX deauth current ap 1311 */ 1312 if (curRate < roamRate || curRssi < roamRssi) { 1313 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1314 /* 1315 * Scan cache contents are too old; force a scan now 1316 * if possible so we have current state to make a 1317 * decision with. We don't kick off a bg scan if 1318 * we're using dynamic turbo and boosted or if the 1319 * channel is busy. 1320 * XXX force immediate switch on scan complete 1321 */ 1322 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1323 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) 1324 ieee80211_bg_scan(vap, 0); 1325 return; 1326 } 1327 se->base.se_rssi = curRssi; 1328 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1329 if (selbs != NULL && selbs != se) { 1330 struct ieee80211_channel *chan; 1331 1332 IEEE80211_DPRINTF(vap, 1333 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1334 "%s: ROAM: curRate %u, roamRate %u, " 1335 "curRssi %d, roamRssi %d\n", __func__, 1336 curRate, roamRate, curRssi, roamRssi); 1337 1338 chan = selbs->base.se_chan; 1339 if (selbs->se_flags & STA_DEMOTE11B) 1340 chan = demote11b(vap, chan); 1341 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1342 } 1343 } 1344 } 1345 1346 /* 1347 * Age entries in the scan cache. 1348 * XXX also do roaming since it's convenient 1349 */ 1350 static void 1351 sta_age(struct ieee80211_scan_state *ss) 1352 { 1353 struct ieee80211vap *vap = ss->ss_vap; 1354 1355 adhoc_age(ss); 1356 /* 1357 * If rate control is enabled check periodically to see if 1358 * we should roam from our current connection to one that 1359 * might be better. This only applies when we're operating 1360 * in sta mode and automatic roaming is set. 1361 * XXX defer if busy 1362 * XXX repeater station 1363 * XXX do when !bgscan? 1364 */ 1365 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1366 ("wrong mode %u", vap->iv_opmode)); 1367 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1368 (vap->iv_ic->ic_flags & IEEE80211_F_BGSCAN) && 1369 vap->iv_state >= IEEE80211_S_RUN) 1370 /* XXX vap is implicit */ 1371 sta_roam_check(ss, vap); 1372 } 1373 1374 /* 1375 * Iterate over the entries in the scan cache, invoking 1376 * the callback function on each one. 1377 */ 1378 static void 1379 sta_iterate(struct ieee80211_scan_state *ss, 1380 ieee80211_scan_iter_func *f, void *arg) 1381 { 1382 struct sta_table *st = ss->ss_priv; 1383 struct sta_entry *se; 1384 u_int gen; 1385 1386 lockmgr(&st->st_scanlock, LK_EXCLUSIVE); 1387 gen = st->st_scaniter++; 1388 restart: 1389 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1390 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1391 if (se->se_scangen != gen) { 1392 se->se_scangen = gen; 1393 /* update public state */ 1394 se->base.se_age = ticks - se->se_lastupdate; 1395 lockmgr(&st->st_lock, LK_RELEASE); 1396 (*f)(arg, &se->base); 1397 goto restart; 1398 } 1399 } 1400 lockmgr(&st->st_lock, LK_RELEASE); 1401 1402 lockmgr(&st->st_scanlock, LK_RELEASE); 1403 } 1404 1405 static void 1406 sta_assoc_fail(struct ieee80211_scan_state *ss, 1407 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1408 { 1409 struct sta_table *st = ss->ss_priv; 1410 struct sta_entry *se; 1411 1412 se = sta_lookup(st, macaddr); 1413 if (se != NULL) { 1414 se->se_fails++; 1415 se->se_lastfail = ticks; 1416 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1417 macaddr, "%s: reason %u fails %u", 1418 __func__, reason, se->se_fails); 1419 } 1420 } 1421 1422 static void 1423 sta_assoc_success(struct ieee80211_scan_state *ss, 1424 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1425 { 1426 struct sta_table *st = ss->ss_priv; 1427 struct sta_entry *se; 1428 1429 se = sta_lookup(st, macaddr); 1430 if (se != NULL) { 1431 #if 0 1432 se->se_fails = 0; 1433 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1434 macaddr, "%s: fails %u", 1435 __func__, se->se_fails); 1436 #endif 1437 se->se_lastassoc = ticks; 1438 } 1439 } 1440 1441 static const struct ieee80211_scanner sta_default = { 1442 .scan_name = "default", 1443 .scan_attach = sta_attach, 1444 .scan_detach = sta_detach, 1445 .scan_start = sta_start, 1446 .scan_restart = sta_restart, 1447 .scan_cancel = sta_cancel, 1448 .scan_end = sta_pick_bss, 1449 .scan_flush = sta_flush, 1450 .scan_add = sta_add, 1451 .scan_age = sta_age, 1452 .scan_iterate = sta_iterate, 1453 .scan_assoc_fail = sta_assoc_fail, 1454 .scan_assoc_success = sta_assoc_success, 1455 }; 1456 IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); 1457 1458 /* 1459 * Adhoc mode-specific support. 1460 */ 1461 1462 static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1463 { 5180, 5200, 5220, 5240 }; 1464 static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1465 { 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1466 static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1467 { 5170, 5190, 5210, 5230 }; 1468 static const uint16_t adhoc11b[] = /* 10, 11 */ 1469 { 2457, 2462 }; 1470 1471 static const struct scanlist adhocScanTable[] = { 1472 { IEEE80211_MODE_11B, X(adhoc11b) }, 1473 { IEEE80211_MODE_11A, X(adhocWorld) }, 1474 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1475 { IEEE80211_MODE_11B, X(adhocMkk) }, 1476 { .list = NULL } 1477 }; 1478 #undef X 1479 1480 /* 1481 * Start an adhoc-mode scan by populating the channel list. 1482 */ 1483 static int 1484 adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1485 { 1486 struct sta_table *st = ss->ss_priv; 1487 1488 makescanlist(ss, vap, adhocScanTable); 1489 1490 if (ss->ss_mindwell == 0) 1491 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1492 if (ss->ss_maxdwell == 0) 1493 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1494 1495 st->st_scangen++; 1496 st->st_newscan = 1; 1497 1498 return 0; 1499 } 1500 1501 /* 1502 * Select a channel to start an adhoc network on. 1503 * The channel list was populated with appropriate 1504 * channels so select one that looks least occupied. 1505 */ 1506 static struct ieee80211_channel * 1507 adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1508 { 1509 struct sta_table *st = ss->ss_priv; 1510 struct sta_entry *se; 1511 struct ieee80211_channel *c, *bestchan; 1512 int i, bestrssi, maxrssi; 1513 1514 bestchan = NULL; 1515 bestrssi = -1; 1516 1517 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1518 for (i = 0; i < ss->ss_last; i++) { 1519 c = ss->ss_chans[i]; 1520 /* never consider a channel with radar */ 1521 if (IEEE80211_IS_CHAN_RADAR(c)) 1522 continue; 1523 /* skip channels disallowed by regulatory settings */ 1524 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1525 continue; 1526 /* check channel attributes for band compatibility */ 1527 if (flags != 0 && (c->ic_flags & flags) != flags) 1528 continue; 1529 maxrssi = 0; 1530 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1531 if (se->base.se_chan != c) 1532 continue; 1533 if (se->base.se_rssi > maxrssi) 1534 maxrssi = se->base.se_rssi; 1535 } 1536 if (bestchan == NULL || maxrssi < bestrssi) 1537 bestchan = c; 1538 } 1539 lockmgr(&st->st_lock, LK_RELEASE); 1540 1541 return bestchan; 1542 } 1543 1544 /* 1545 * Pick an ibss network to join or find a channel 1546 * to use to start an ibss network. 1547 */ 1548 static int 1549 adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1550 { 1551 struct sta_table *st = ss->ss_priv; 1552 struct sta_entry *selbs; 1553 struct ieee80211_channel *chan; 1554 1555 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1556 vap->iv_opmode == IEEE80211_M_AHDEMO || 1557 vap->iv_opmode == IEEE80211_M_MBSS, 1558 ("wrong opmode %u", vap->iv_opmode)); 1559 1560 if (st->st_newscan) { 1561 sta_update_notseen(st); 1562 st->st_newscan = 0; 1563 } 1564 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1565 /* 1566 * Manual/background scan, don't select+join the 1567 * bss, just return. The scanning framework will 1568 * handle notification that this has completed. 1569 */ 1570 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1571 return 1; 1572 } 1573 /* 1574 * Automatic sequencing; look for a candidate and 1575 * if found join the network. 1576 */ 1577 /* NB: unlocked read should be ok */ 1578 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1579 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1580 "%s: no scan candidate\n", __func__); 1581 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1582 return 0; 1583 notfound: 1584 /* NB: never auto-start a tdma network for slot !0 */ 1585 #ifdef IEEE80211_SUPPORT_TDMA 1586 if (vap->iv_des_nssid && 1587 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || 1588 ieee80211_tdma_getslot(vap) == 0)) { 1589 #else 1590 if (vap->iv_des_nssid) { 1591 #endif 1592 /* 1593 * No existing adhoc network to join and we have 1594 * an ssid; start one up. If no channel was 1595 * specified, try to select a channel. 1596 */ 1597 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1598 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1599 struct ieee80211com *ic = vap->iv_ic; 1600 1601 chan = adhoc_pick_channel(ss, 0); 1602 if (chan != NULL) 1603 chan = ieee80211_ht_adjust_channel(ic, 1604 chan, vap->iv_flags_ht); 1605 } else 1606 chan = vap->iv_des_chan; 1607 if (chan != NULL) { 1608 ieee80211_create_ibss(vap, chan); 1609 return 1; 1610 } 1611 } 1612 /* 1613 * If nothing suitable was found decrement 1614 * the failure counts so entries will be 1615 * reconsidered the next time around. We 1616 * really want to do this only for sta's 1617 * where we've previously had some success. 1618 */ 1619 sta_dec_fails(st); 1620 st->st_newscan = 1; 1621 return 0; /* restart scan */ 1622 } 1623 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1624 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1625 return (selbs != NULL); 1626 if (selbs == NULL) 1627 goto notfound; 1628 chan = selbs->base.se_chan; 1629 if (selbs->se_flags & STA_DEMOTE11B) 1630 chan = demote11b(vap, chan); 1631 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1632 goto notfound; 1633 return 1; /* terminate scan */ 1634 } 1635 1636 /* 1637 * Age entries in the scan cache. 1638 */ 1639 static void 1640 adhoc_age(struct ieee80211_scan_state *ss) 1641 { 1642 struct sta_table *st = ss->ss_priv; 1643 struct sta_entry *se, *next; 1644 1645 lockmgr(&st->st_lock, LK_EXCLUSIVE); 1646 TAILQ_FOREACH_MUTABLE(se, &st->st_entry, se_list, next) { 1647 if (se->se_notseen > STA_PURGE_SCANS) { 1648 TAILQ_REMOVE(&st->st_entry, se, se_list); 1649 LIST_REMOVE(se, se_hash); 1650 ieee80211_ies_cleanup(&se->base.se_ies); 1651 kfree(se, M_80211_SCAN); 1652 } 1653 } 1654 lockmgr(&st->st_lock, LK_RELEASE); 1655 } 1656 1657 static const struct ieee80211_scanner adhoc_default = { 1658 .scan_name = "default", 1659 .scan_attach = sta_attach, 1660 .scan_detach = sta_detach, 1661 .scan_start = adhoc_start, 1662 .scan_restart = sta_restart, 1663 .scan_cancel = sta_cancel, 1664 .scan_end = adhoc_pick_bss, 1665 .scan_flush = sta_flush, 1666 .scan_pickchan = adhoc_pick_channel, 1667 .scan_add = sta_add, 1668 .scan_age = adhoc_age, 1669 .scan_iterate = sta_iterate, 1670 .scan_assoc_fail = sta_assoc_fail, 1671 .scan_assoc_success = sta_assoc_success, 1672 }; 1673 IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1674 IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1675 1676 static void 1677 ap_force_promisc(struct ieee80211com *ic) 1678 { 1679 struct ifnet *ifp = ic->ic_ifp; 1680 1681 /* set interface into promiscuous mode */ 1682 ifp->if_flags |= IFF_PROMISC; 1683 ieee80211_runtask(ic, &ic->ic_promisc_task); 1684 } 1685 1686 static void 1687 ap_reset_promisc(struct ieee80211com *ic) 1688 { 1689 ieee80211_syncifflag_locked(ic, IFF_PROMISC); 1690 } 1691 1692 static int 1693 ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1694 { 1695 struct sta_table *st = ss->ss_priv; 1696 1697 makescanlist(ss, vap, staScanTable); 1698 1699 if (ss->ss_mindwell == 0) 1700 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1701 if (ss->ss_maxdwell == 0) 1702 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1703 1704 st->st_scangen++; 1705 st->st_newscan = 1; 1706 1707 ap_force_promisc(vap->iv_ic); 1708 return 0; 1709 } 1710 1711 /* 1712 * Cancel an ongoing scan. 1713 */ 1714 static int 1715 ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1716 { 1717 ap_reset_promisc(vap->iv_ic); 1718 return 0; 1719 } 1720 1721 /* 1722 * Pick a quiet channel to use for ap operation. 1723 */ 1724 static struct ieee80211_channel * 1725 ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1726 { 1727 struct sta_table *st = ss->ss_priv; 1728 struct ieee80211_channel *bestchan = NULL; 1729 int i; 1730 1731 /* XXX select channel more intelligently, e.g. channel spread, power */ 1732 /* NB: use scan list order to preserve channel preference */ 1733 for (i = 0; i < ss->ss_last; i++) { 1734 struct ieee80211_channel *chan = ss->ss_chans[i]; 1735 /* 1736 * If the channel is unoccupied the max rssi 1737 * should be zero; just take it. Otherwise 1738 * track the channel with the lowest rssi and 1739 * use that when all channels appear occupied. 1740 */ 1741 if (IEEE80211_IS_CHAN_RADAR(chan)) 1742 continue; 1743 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1744 continue; 1745 /* check channel attributes for band compatibility */ 1746 if (flags != 0 && (chan->ic_flags & flags) != flags) 1747 continue; 1748 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); 1749 /* XXX channel have interference */ 1750 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1751 /* XXX use other considerations */ 1752 return chan; 1753 } 1754 if (bestchan == NULL || 1755 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1756 bestchan = chan; 1757 } 1758 return bestchan; 1759 } 1760 1761 /* 1762 * Pick a quiet channel to use for ap operation. 1763 */ 1764 static int 1765 ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1766 { 1767 struct ieee80211com *ic = vap->iv_ic; 1768 struct ieee80211_channel *bestchan; 1769 1770 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1771 ("wrong opmode %u", vap->iv_opmode)); 1772 bestchan = ap_pick_channel(ss, 0); 1773 if (bestchan == NULL) { 1774 /* no suitable channel, should not happen */ 1775 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1776 "%s: no suitable channel! (should not happen)\n", __func__); 1777 /* XXX print something? */ 1778 return 0; /* restart scan */ 1779 } 1780 /* 1781 * If this is a dynamic turbo channel, start with the unboosted one. 1782 */ 1783 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1784 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1785 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1786 if (bestchan == NULL) { 1787 /* should never happen ?? */ 1788 return 0; 1789 } 1790 } 1791 ap_reset_promisc(ic); 1792 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1793 /* 1794 * Manual/background scan, don't select+join the 1795 * bss, just return. The scanning framework will 1796 * handle notification that this has completed. 1797 */ 1798 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1799 return 1; 1800 } 1801 ieee80211_create_ibss(vap, 1802 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht)); 1803 return 1; 1804 } 1805 1806 static const struct ieee80211_scanner ap_default = { 1807 .scan_name = "default", 1808 .scan_attach = sta_attach, 1809 .scan_detach = sta_detach, 1810 .scan_start = ap_start, 1811 .scan_restart = sta_restart, 1812 .scan_cancel = ap_cancel, 1813 .scan_end = ap_end, 1814 .scan_flush = sta_flush, 1815 .scan_pickchan = ap_pick_channel, 1816 .scan_add = sta_add, 1817 .scan_age = adhoc_age, 1818 .scan_iterate = sta_iterate, 1819 .scan_assoc_success = sta_assoc_success, 1820 .scan_assoc_fail = sta_assoc_fail, 1821 }; 1822 IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1823 1824 #ifdef IEEE80211_SUPPORT_MESH 1825 /* 1826 * Pick an mbss network to join or find a channel 1827 * to use to start an mbss network. 1828 */ 1829 static int 1830 mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1831 { 1832 struct sta_table *st = ss->ss_priv; 1833 struct ieee80211_mesh_state *ms = vap->iv_mesh; 1834 struct sta_entry *selbs; 1835 struct ieee80211_channel *chan; 1836 1837 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, 1838 ("wrong opmode %u", vap->iv_opmode)); 1839 1840 if (st->st_newscan) { 1841 sta_update_notseen(st); 1842 st->st_newscan = 0; 1843 } 1844 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1845 /* 1846 * Manual/background scan, don't select+join the 1847 * bss, just return. The scanning framework will 1848 * handle notification that this has completed. 1849 */ 1850 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1851 return 1; 1852 } 1853 /* 1854 * Automatic sequencing; look for a candidate and 1855 * if found join the network. 1856 */ 1857 /* NB: unlocked read should be ok */ 1858 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1859 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1860 "%s: no scan candidate\n", __func__); 1861 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1862 return 0; 1863 notfound: 1864 if (ms->ms_idlen != 0) { 1865 /* 1866 * No existing mbss network to join and we have 1867 * a meshid; start one up. If no channel was 1868 * specified, try to select a channel. 1869 */ 1870 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1871 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1872 struct ieee80211com *ic = vap->iv_ic; 1873 1874 chan = adhoc_pick_channel(ss, 0); 1875 if (chan != NULL) 1876 chan = ieee80211_ht_adjust_channel(ic, 1877 chan, vap->iv_flags_ht); 1878 } else 1879 chan = vap->iv_des_chan; 1880 if (chan != NULL) { 1881 ieee80211_create_ibss(vap, chan); 1882 return 1; 1883 } 1884 } 1885 /* 1886 * If nothing suitable was found decrement 1887 * the failure counts so entries will be 1888 * reconsidered the next time around. We 1889 * really want to do this only for sta's 1890 * where we've previously had some success. 1891 */ 1892 sta_dec_fails(st); 1893 st->st_newscan = 1; 1894 return 0; /* restart scan */ 1895 } 1896 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1897 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1898 return (selbs != NULL); 1899 if (selbs == NULL) 1900 goto notfound; 1901 chan = selbs->base.se_chan; 1902 if (selbs->se_flags & STA_DEMOTE11B) 1903 chan = demote11b(vap, chan); 1904 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1905 goto notfound; 1906 return 1; /* terminate scan */ 1907 } 1908 1909 static const struct ieee80211_scanner mesh_default = { 1910 .scan_name = "default", 1911 .scan_attach = sta_attach, 1912 .scan_detach = sta_detach, 1913 .scan_start = adhoc_start, 1914 .scan_restart = sta_restart, 1915 .scan_cancel = sta_cancel, 1916 .scan_end = mesh_pick_bss, 1917 .scan_flush = sta_flush, 1918 .scan_pickchan = adhoc_pick_channel, 1919 .scan_add = sta_add, 1920 .scan_age = adhoc_age, 1921 .scan_iterate = sta_iterate, 1922 .scan_assoc_fail = sta_assoc_fail, 1923 .scan_assoc_success = sta_assoc_success, 1924 }; 1925 IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); 1926 #endif /* IEEE80211_SUPPORT_MESH */ 1927