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_var.h> 43 #include <net/if_media.h> 44 #include <net/ethernet.h> 45 46 #include <netproto/802_11/ieee80211_var.h> 47 #include <netproto/802_11/ieee80211_input.h> 48 #include <netproto/802_11/ieee80211_regdomain.h> 49 #ifdef IEEE80211_SUPPORT_TDMA 50 #include <netproto/802_11/ieee80211_tdma.h> 51 #endif 52 #ifdef IEEE80211_SUPPORT_MESH 53 #include <netproto/802_11/ieee80211_mesh.h> 54 #endif 55 #include <netproto/802_11/ieee80211_ratectl.h> 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 ieee80211_scan_table_lock_t st_lock; /* on scan table */ 103 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 104 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 105 #if defined(__DragonFly__) 106 struct lock st_scanlock; /* on st_scaniter */ 107 #else 108 struct mtx st_scanlock; /* on st_scaniter */ 109 #endif 110 u_int st_scaniter; /* gen# for iterator */ 111 u_int st_scangen; /* scan generation # */ 112 int st_newscan; 113 /* ap-related state */ 114 int st_maxrssi[MAX_IEEE_CHAN]; 115 }; 116 117 static void sta_flush_table(struct sta_table *); 118 /* 119 * match_bss returns a bitmask describing if an entry is suitable 120 * for use. If non-zero the entry was deemed not suitable and it's 121 * contents explains why. The following flags are or'd to to this 122 * mask and can be used to figure out why the entry was rejected. 123 */ 124 #define MATCH_CHANNEL 0x00001 /* channel mismatch */ 125 #define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ 126 #define MATCH_PRIVACY 0x00004 /* privacy mismatch */ 127 #define MATCH_RATE 0x00008 /* rate set mismatch */ 128 #define MATCH_SSID 0x00010 /* ssid mismatch */ 129 #define MATCH_BSSID 0x00020 /* bssid mismatch */ 130 #define MATCH_FAILS 0x00040 /* too many failed auth attempts */ 131 #define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ 132 #define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ 133 #define MATCH_CC 0x00200 /* country code mismatch */ 134 #define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ 135 #define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ 136 #define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ 137 #define MATCH_TDMA_LOCAL 0x02000 /* local address */ 138 #define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ 139 #define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ 140 #define MATCH_MESHID 0x20000 /* meshid mismatch */ 141 static int match_bss(struct ieee80211vap *, 142 const struct ieee80211_scan_state *, struct sta_entry *, int); 143 static void adhoc_age(struct ieee80211_scan_state *); 144 145 static __inline int 146 isocmp(const uint8_t cc1[], const uint8_t cc2[]) 147 { 148 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 149 } 150 151 /* number of references from net80211 layer */ 152 static int nrefs = 0; 153 /* 154 * Module glue. 155 */ 156 IEEE80211_SCANNER_MODULE(sta, 1); 157 158 /* 159 * Attach prior to any scanning work. 160 */ 161 static int 162 sta_attach(struct ieee80211_scan_state *ss) 163 { 164 struct sta_table *st; 165 166 st = (struct sta_table *) kmalloc(sizeof(struct sta_table), 167 M_80211_SCAN, M_INTWAIT | M_ZERO); 168 if (st == NULL) 169 return 0; 170 IEEE80211_SCAN_TABLE_LOCK_INIT(st, "scantable"); 171 #if defined(__DragonFly__) 172 lockinit(&st->st_scanlock, "scangen", 0, 0); 173 #else 174 mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF); 175 #endif 176 TAILQ_INIT(&st->st_entry); 177 ss->ss_priv = st; 178 nrefs++; /* NB: we assume caller locking */ 179 return 1; 180 } 181 182 /* 183 * Cleanup any private state. 184 */ 185 static int 186 sta_detach(struct ieee80211_scan_state *ss) 187 { 188 struct sta_table *st = ss->ss_priv; 189 190 if (st != NULL) { 191 sta_flush_table(st); 192 IEEE80211_SCAN_TABLE_LOCK_DESTROY(st); 193 #if defined(__DragonFly__) 194 lockuninit(&st->st_scanlock); 195 #else 196 mtx_destroy(&st->st_scanlock); 197 #endif 198 kfree(st, M_80211_SCAN); 199 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 200 nrefs--; /* NB: we assume caller locking */ 201 } 202 return 1; 203 } 204 205 /* 206 * Flush all per-scan state. 207 */ 208 static int 209 sta_flush(struct ieee80211_scan_state *ss) 210 { 211 struct sta_table *st = ss->ss_priv; 212 213 IEEE80211_SCAN_TABLE_LOCK(st); 214 sta_flush_table(st); 215 IEEE80211_SCAN_TABLE_UNLOCK(st); 216 ss->ss_last = 0; 217 return 0; 218 } 219 220 /* 221 * Flush all entries in the scan cache. 222 */ 223 static void 224 sta_flush_table(struct sta_table *st) 225 { 226 struct sta_entry *se, *next; 227 228 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 229 TAILQ_REMOVE(&st->st_entry, se, se_list); 230 LIST_REMOVE(se, se_hash); 231 ieee80211_ies_cleanup(&se->base.se_ies); 232 kfree(se, M_80211_SCAN); 233 } 234 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 235 } 236 237 /* 238 * Process a beacon or probe response frame; create an 239 * entry in the scan cache or update any previous entry. 240 */ 241 static int 242 sta_add(struct ieee80211_scan_state *ss, 243 const struct ieee80211_scanparams *sp, 244 const struct ieee80211_frame *wh, 245 int subtype, int rssi, int noise) 246 { 247 #define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 248 #define PICK1ST(_ss) \ 249 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 250 IEEE80211_SCAN_PICK1ST) 251 struct sta_table *st = ss->ss_priv; 252 const uint8_t *macaddr = wh->i_addr2; 253 struct ieee80211vap *vap = ss->ss_vap; 254 struct ieee80211com *ic = vap->iv_ic; 255 struct ieee80211_channel *c; 256 struct sta_entry *se; 257 struct ieee80211_scan_entry *ise; 258 int hash; 259 260 hash = STA_HASH(macaddr); 261 262 IEEE80211_SCAN_TABLE_LOCK(st); 263 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 264 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 265 goto found; 266 se = (struct sta_entry *) kmalloc(sizeof(struct sta_entry), 267 M_80211_SCAN, M_INTWAIT | M_ZERO); 268 if (se == NULL) { 269 IEEE80211_SCAN_TABLE_UNLOCK(st); 270 return 0; 271 } 272 se->se_scangen = st->st_scaniter-1; 273 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 274 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 275 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 276 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 277 found: 278 ise = &se->base; 279 /* XXX ap beaconing multiple ssid w/ same bssid */ 280 if (sp->ssid[1] != 0 && 281 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 282 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 283 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 284 ("rate set too large: %u", sp->rates[1])); 285 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 286 if (sp->xrates != NULL) { 287 /* XXX validate xrates[1] */ 288 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 289 ("xrate set too large: %u", sp->xrates[1])); 290 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 291 } else 292 ise->se_xrates[1] = 0; 293 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 294 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 295 /* 296 * Record rssi data using extended precision LPF filter. 297 * 298 * NB: use only on-channel data to insure we get a good 299 * estimate of the signal we'll see when associated. 300 */ 301 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 302 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 303 ise->se_noise = noise; 304 } 305 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 306 ise->se_intval = sp->bintval; 307 ise->se_capinfo = sp->capinfo; 308 #ifdef IEEE80211_SUPPORT_MESH 309 if (sp->meshid != NULL && sp->meshid[1] != 0) 310 memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); 311 #endif 312 /* 313 * Beware of overriding se_chan for frames seen 314 * off-channel; this can cause us to attempt an 315 * association on the wrong channel. 316 */ 317 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 318 /* 319 * Off-channel, locate the home/bss channel for the sta 320 * using the value broadcast in the DSPARMS ie. We know 321 * sp->chan has this value because it's used to calculate 322 * IEEE80211_BPARSE_OFFCHAN. 323 */ 324 c = ieee80211_find_channel_byieee(ic, sp->chan, 325 ic->ic_curchan->ic_flags); 326 if (c != NULL) { 327 ise->se_chan = c; 328 } else if (ise->se_chan == NULL) { 329 /* should not happen, pick something */ 330 ise->se_chan = ic->ic_curchan; 331 } 332 } else 333 ise->se_chan = ic->ic_curchan; 334 if (IEEE80211_IS_CHAN_HT(ise->se_chan) && sp->htcap == NULL) { 335 /* Demote legacy networks to a non-HT channel. */ 336 c = ieee80211_find_channel(ic, ise->se_chan->ic_freq, 337 ise->se_chan->ic_flags & ~IEEE80211_CHAN_HT); 338 KASSERT(c != NULL, 339 ("no legacy channel %u", ise->se_chan->ic_ieee)); 340 ise->se_chan = c; 341 } 342 ise->se_fhdwell = sp->fhdwell; 343 ise->se_fhindex = sp->fhindex; 344 ise->se_erp = sp->erp; 345 ise->se_timoff = sp->timoff; 346 if (sp->tim != NULL) { 347 const struct ieee80211_tim_ie *tim = 348 (const struct ieee80211_tim_ie *) sp->tim; 349 ise->se_dtimperiod = tim->tim_period; 350 } 351 if (sp->country != NULL) { 352 const struct ieee80211_country_ie *cie = 353 (const struct ieee80211_country_ie *) sp->country; 354 /* 355 * If 11d is enabled and we're attempting to join a bss 356 * that advertises it's country code then compare our 357 * current settings to what we fetched from the country ie. 358 * If our country code is unspecified or different then 359 * dispatch an event to user space that identifies the 360 * country code so our regdomain config can be changed. 361 */ 362 /* XXX only for STA mode? */ 363 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 364 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 365 (ic->ic_regdomain.country == CTRY_DEFAULT || 366 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 367 /* only issue one notify event per scan */ 368 if (se->se_countrygen != st->st_scangen) { 369 ieee80211_notify_country(vap, ise->se_bssid, 370 cie->cc); 371 se->se_countrygen = st->st_scangen; 372 } 373 } 374 ise->se_cc[0] = cie->cc[0]; 375 ise->se_cc[1] = cie->cc[1]; 376 } 377 /* NB: no need to setup ie ptrs; they are not (currently) used */ 378 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 379 380 /* clear failure count after STA_FAIL_AGE passes */ 381 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 382 se->se_fails = 0; 383 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 384 "%s: fails %u", __func__, se->se_fails); 385 } 386 387 se->se_lastupdate = ticks; /* update time */ 388 se->se_seen = 1; 389 se->se_notseen = 0; 390 391 KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); 392 if (rssi > st->st_maxrssi[sp->bchan]) 393 st->st_maxrssi[sp->bchan] = rssi; 394 395 IEEE80211_SCAN_TABLE_UNLOCK(st); 396 397 /* 398 * If looking for a quick choice and nothing's 399 * been found check here. 400 */ 401 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 402 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 403 404 return 1; 405 #undef PICK1ST 406 #undef ISPROBE 407 } 408 409 /* 410 * Check if a channel is excluded by user request. 411 */ 412 static int 413 isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 414 { 415 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 416 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 417 c->ic_freq != vap->iv_des_chan->ic_freq)); 418 } 419 420 static struct ieee80211_channel * 421 find11gchannel(struct ieee80211com *ic, int i, int freq) 422 { 423 struct ieee80211_channel *c; 424 int j; 425 426 /* 427 * The normal ordering in the channel list is b channel 428 * immediately followed by g so optimize the search for 429 * this. We'll still do a full search just in case. 430 */ 431 for (j = i+1; j < ic->ic_nchans; j++) { 432 c = &ic->ic_channels[j]; 433 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 434 return c; 435 } 436 for (j = 0; j < i; j++) { 437 c = &ic->ic_channels[j]; 438 if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) 439 return c; 440 } 441 return NULL; 442 } 443 444 static const u_int chanflags[IEEE80211_MODE_MAX] = { 445 [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, 446 [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, 447 [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, 448 [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, 449 [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, 450 /* check base channel */ 451 [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, 452 [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, 453 [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, 454 [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, 455 [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, 456 /* check legacy */ 457 [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, 458 [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, 459 }; 460 461 static void 462 add_channels(struct ieee80211vap *vap, 463 struct ieee80211_scan_state *ss, 464 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 465 { 466 struct ieee80211com *ic = vap->iv_ic; 467 struct ieee80211_channel *c, *cg; 468 u_int modeflags; 469 int i; 470 471 KASSERT(mode < nitems(chanflags), ("Unexpected mode %u", mode)); 472 modeflags = chanflags[mode]; 473 for (i = 0; i < nfreq; i++) { 474 if (ss->ss_last >= IEEE80211_SCAN_MAX) 475 break; 476 477 c = ieee80211_find_channel(ic, freq[i], modeflags); 478 if (c == NULL || isexcluded(vap, c)) 479 continue; 480 if (mode == IEEE80211_MODE_AUTO) { 481 /* 482 * XXX special-case 11b/g channels so we select 483 * the g channel if both are present. 484 */ 485 if (IEEE80211_IS_CHAN_B(c) && 486 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 487 c = cg; 488 } 489 ss->ss_chans[ss->ss_last++] = c; 490 } 491 } 492 493 struct scanlist { 494 uint16_t mode; 495 uint16_t count; 496 const uint16_t *list; 497 }; 498 499 static int 500 checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 501 { 502 int i; 503 504 for (; scan->list != NULL; scan++) { 505 for (i = 0; i < scan->count; i++) 506 if (scan->list[i] == c->ic_freq) 507 return 1; 508 } 509 return 0; 510 } 511 512 static int 513 onscanlist(const struct ieee80211_scan_state *ss, 514 const struct ieee80211_channel *c) 515 { 516 int i; 517 518 for (i = 0; i < ss->ss_last; i++) 519 if (ss->ss_chans[i] == c) 520 return 1; 521 return 0; 522 } 523 524 static void 525 sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 526 const struct scanlist table[]) 527 { 528 struct ieee80211com *ic = vap->iv_ic; 529 struct ieee80211_channel *c; 530 int i; 531 532 for (i = 0; i < ic->ic_nchans; i++) { 533 if (ss->ss_last >= IEEE80211_SCAN_MAX) 534 break; 535 536 c = &ic->ic_channels[i]; 537 /* 538 * Ignore dynamic turbo channels; we scan them 539 * in normal mode (i.e. not boosted). Likewise 540 * for HT channels, they get scanned using 541 * legacy rates. 542 */ 543 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) 544 continue; 545 546 /* 547 * If a desired mode was specified, scan only 548 * channels that satisfy that constraint. 549 */ 550 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 551 vap->iv_des_mode != ieee80211_chan2mode(c)) 552 continue; 553 554 /* 555 * Skip channels excluded by user request. 556 */ 557 if (isexcluded(vap, c)) 558 continue; 559 560 /* 561 * Add the channel unless it is listed in the 562 * fixed scan order tables. This insures we 563 * don't sweep back in channels we filtered out 564 * above. 565 */ 566 if (checktable(table, c)) 567 continue; 568 569 /* Add channel to scanning list. */ 570 ss->ss_chans[ss->ss_last++] = c; 571 } 572 /* 573 * Explicitly add any desired channel if: 574 * - not already on the scan list 575 * - allowed by any desired mode constraint 576 * - there is space in the scan list 577 * This allows the channel to be used when the filtering 578 * mechanisms would otherwise elide it (e.g HT, turbo). 579 */ 580 c = vap->iv_des_chan; 581 if (c != IEEE80211_CHAN_ANYC && 582 !onscanlist(ss, c) && 583 (vap->iv_des_mode == IEEE80211_MODE_AUTO || 584 vap->iv_des_mode == ieee80211_chan2mode(c)) && 585 ss->ss_last < IEEE80211_SCAN_MAX) 586 ss->ss_chans[ss->ss_last++] = c; 587 } 588 589 static void 590 makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 591 const struct scanlist table[]) 592 { 593 const struct scanlist *scan; 594 enum ieee80211_phymode mode; 595 596 ss->ss_last = 0; 597 /* 598 * Use the table of ordered channels to construct the list 599 * of channels for scanning. Any channels in the ordered 600 * list not in the master list will be discarded. 601 */ 602 for (scan = table; scan->list != NULL; scan++) { 603 mode = scan->mode; 604 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { 605 /* 606 * If a desired mode was specified, scan only 607 * channels that satisfy that constraint. 608 */ 609 if (vap->iv_des_mode != mode) { 610 /* 611 * The scan table marks 2.4Ghz channels as b 612 * so if the desired mode is 11g, then use 613 * the 11b channel list but upgrade the mode. 614 */ 615 if (vap->iv_des_mode != IEEE80211_MODE_11G || 616 mode != IEEE80211_MODE_11B) 617 continue; 618 mode = IEEE80211_MODE_11G; /* upgrade */ 619 } 620 } else { 621 /* 622 * This lets add_channels upgrade an 11b channel 623 * to 11g if available. 624 */ 625 if (mode == IEEE80211_MODE_11B) 626 mode = IEEE80211_MODE_AUTO; 627 } 628 #ifdef IEEE80211_F_XR 629 /* XR does not operate on turbo channels */ 630 if ((vap->iv_flags & IEEE80211_F_XR) && 631 (mode == IEEE80211_MODE_TURBO_A || 632 mode == IEEE80211_MODE_TURBO_G || 633 mode == IEEE80211_MODE_STURBO_A)) 634 continue; 635 #endif 636 /* 637 * Add the list of the channels; any that are not 638 * in the master channel list will be discarded. 639 */ 640 add_channels(vap, ss, mode, scan->list, scan->count); 641 } 642 643 /* 644 * Add the channels from the ic that are not present 645 * in the table. 646 */ 647 sweepchannels(ss, vap, table); 648 } 649 650 static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 651 { 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 652 static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 653 { 5170, 5190, 5210, 5230 }; 654 static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 655 { 2412, 2437, 2462, 2442, 2472 }; 656 static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 657 { 5745, 5765, 5785, 5805, 5825 }; 658 static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 659 { 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 660 static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 661 { 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 662 static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 663 { 2484 }; 664 static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 665 { 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 666 static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 667 { 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 668 #ifdef ATH_TURBO_SCAN 669 static const uint16_t rcl5[] = /* 3 static turbo channels */ 670 { 5210, 5250, 5290 }; 671 static const uint16_t rcl6[] = /* 2 static turbo channels */ 672 { 5760, 5800 }; 673 static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 674 { 5540, 5580, 5620, 5660 }; 675 static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 676 { 2437 }; 677 static const uint16_t rcl13[] = /* dynamic Turbo channels */ 678 { 5200, 5240, 5280, 5765, 5805 }; 679 #endif /* ATH_TURBO_SCAN */ 680 681 #define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 682 683 static const struct scanlist staScanTable[] = { 684 { IEEE80211_MODE_11B, X(rcl3) }, 685 { IEEE80211_MODE_11A, X(rcl1) }, 686 { IEEE80211_MODE_11A, X(rcl2) }, 687 { IEEE80211_MODE_11B, X(rcl8) }, 688 { IEEE80211_MODE_11B, X(rcl9) }, 689 { IEEE80211_MODE_11A, X(rcl4) }, 690 #ifdef ATH_TURBO_SCAN 691 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 692 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 693 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 694 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 695 #endif /* ATH_TURBO_SCAN */ 696 { IEEE80211_MODE_11A, X(rcl7) }, 697 { IEEE80211_MODE_11B, X(rcl10) }, 698 { IEEE80211_MODE_11A, X(rcl11) }, 699 #ifdef ATH_TURBO_SCAN 700 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 701 #endif /* ATH_TURBO_SCAN */ 702 { .list = NULL } 703 }; 704 705 /* 706 * Start a station-mode scan by populating the channel list. 707 */ 708 static int 709 sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 710 { 711 struct sta_table *st = ss->ss_priv; 712 713 makescanlist(ss, vap, staScanTable); 714 715 if (ss->ss_mindwell == 0) 716 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 717 if (ss->ss_maxdwell == 0) 718 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 719 720 st->st_scangen++; 721 st->st_newscan = 1; 722 723 return 0; 724 } 725 726 /* 727 * Restart a scan, typically a bg scan but can 728 * also be a fg scan that came up empty. 729 */ 730 static int 731 sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 732 { 733 struct sta_table *st = ss->ss_priv; 734 735 st->st_newscan = 1; 736 return 0; 737 } 738 739 /* 740 * Cancel an ongoing scan. 741 */ 742 static int 743 sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 744 { 745 return 0; 746 } 747 748 /* unaligned little endian access */ 749 #define LE_READ_2(p) \ 750 ((uint16_t) \ 751 ((((const uint8_t *)(p))[0] ) | \ 752 (((const uint8_t *)(p))[1] << 8))) 753 754 /* 755 * Demote any supplied 11g channel to 11b. There should 756 * always be an 11b channel but we check anyway... 757 */ 758 static struct ieee80211_channel * 759 demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 760 { 761 struct ieee80211_channel *c; 762 763 if (IEEE80211_IS_CHAN_ANYG(chan) && 764 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 765 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 766 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 767 IEEE80211_CHAN_B); 768 if (c != NULL) 769 chan = c; 770 } 771 return chan; 772 } 773 774 static int 775 maxrate(const struct ieee80211_scan_entry *se) 776 { 777 const struct ieee80211_ie_htcap *htcap = 778 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 779 int rmax, r, i, txstream; 780 uint16_t caps; 781 uint8_t txparams; 782 783 rmax = 0; 784 if (htcap != NULL) { 785 /* 786 * HT station; inspect supported MCS and then adjust 787 * rate by channel width. 788 */ 789 txparams = htcap->hc_mcsset[12]; 790 if (txparams & 0x3) { 791 /* 792 * TX MCS parameters defined and not equal to RX, 793 * extract the number of spartial streams and 794 * map it to the highest MCS rate. 795 */ 796 txstream = ((txparams & 0xc) >> 2) + 1; 797 i = txstream * 8 - 1; 798 } else 799 for (i = 31; i >= 0 && isclr(htcap->hc_mcsset, i); i--); 800 if (i >= 0) { 801 caps = LE_READ_2(&htcap->hc_cap); 802 if ((caps & IEEE80211_HTCAP_CHWIDTH40) && 803 (caps & IEEE80211_HTCAP_SHORTGI40)) 804 rmax = ieee80211_htrates[i].ht40_rate_400ns; 805 else if (caps & IEEE80211_HTCAP_CHWIDTH40) 806 rmax = ieee80211_htrates[i].ht40_rate_800ns; 807 else if (caps & IEEE80211_HTCAP_SHORTGI20) 808 rmax = ieee80211_htrates[i].ht20_rate_400ns; 809 else 810 rmax = ieee80211_htrates[i].ht20_rate_800ns; 811 } 812 } 813 for (i = 0; i < se->se_rates[1]; i++) { 814 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 815 if (r > rmax) 816 rmax = r; 817 } 818 for (i = 0; i < se->se_xrates[1]; i++) { 819 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 820 if (r > rmax) 821 rmax = r; 822 } 823 return rmax; 824 } 825 826 /* 827 * Compare the capabilities of two entries and decide which is 828 * more desirable (return >0 if a is considered better). Note 829 * that we assume compatibility/usability has already been checked 830 * so we don't need to (e.g. validate whether privacy is supported). 831 * Used to select the best scan candidate for association in a BSS. 832 */ 833 static int 834 sta_compare(const struct sta_entry *a, const struct sta_entry *b) 835 { 836 #define PREFER(_a,_b,_what) do { \ 837 if (((_a) ^ (_b)) & (_what)) \ 838 return ((_a) & (_what)) ? 1 : -1; \ 839 } while (0) 840 int maxa, maxb; 841 int8_t rssia, rssib; 842 int weight; 843 844 /* privacy support */ 845 PREFER(a->base.se_capinfo, b->base.se_capinfo, 846 IEEE80211_CAPINFO_PRIVACY); 847 848 /* compare count of previous failures */ 849 weight = b->se_fails - a->se_fails; 850 if (abs(weight) > 1) 851 return weight; 852 853 /* 854 * Compare rssi. If the two are considered equivalent 855 * then fallback to other criteria. We threshold the 856 * comparisons to avoid selecting an ap purely by rssi 857 * when both values may be good but one ap is otherwise 858 * more desirable (e.g. an 11b-only ap with stronger 859 * signal than an 11g ap). 860 */ 861 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 862 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 863 if (abs(rssib - rssia) < 5) { 864 /* best/max rate preferred if signal level close enough XXX */ 865 maxa = maxrate(&a->base); 866 maxb = maxrate(&b->base); 867 if (maxa != maxb) 868 return maxa - maxb; 869 /* XXX use freq for channel preference */ 870 /* for now just prefer 5Ghz band to all other bands */ 871 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 872 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 873 } 874 /* all things being equal, use signal level */ 875 return a->base.se_rssi - b->base.se_rssi; 876 #undef PREFER 877 } 878 879 /* 880 * Check rate set suitability and return the best supported rate. 881 * XXX inspect MCS for HT 882 */ 883 static int 884 check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 885 const struct ieee80211_scan_entry *se) 886 { 887 #define RV(v) ((v) & IEEE80211_RATE_VAL) 888 const struct ieee80211_rateset *srs; 889 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 890 const uint8_t *rs; 891 892 okrate = badrate = 0; 893 894 srs = ieee80211_get_suprates(vap->iv_ic, chan); 895 nrs = se->se_rates[1]; 896 rs = se->se_rates+2; 897 /* XXX MCS */ 898 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 899 fixedrate = IEEE80211_FIXED_RATE_NONE; 900 again: 901 for (i = 0; i < nrs; i++) { 902 r = RV(rs[i]); 903 badrate = r; 904 /* 905 * Check any fixed rate is included. 906 */ 907 if (r == ucastrate) 908 fixedrate = r; 909 /* 910 * Check against our supported rates. 911 */ 912 for (j = 0; j < srs->rs_nrates; j++) 913 if (r == RV(srs->rs_rates[j])) { 914 if (r > okrate) /* NB: track max */ 915 okrate = r; 916 break; 917 } 918 919 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 920 /* 921 * Don't try joining a BSS, if we don't support 922 * one of its basic rates. 923 */ 924 okrate = 0; 925 goto back; 926 } 927 } 928 if (rs == se->se_rates+2) { 929 /* scan xrates too; sort of an algol68-style for loop */ 930 nrs = se->se_xrates[1]; 931 rs = se->se_xrates+2; 932 goto again; 933 } 934 935 back: 936 if (okrate == 0 || ucastrate != fixedrate) 937 return badrate | IEEE80211_RATE_BASIC; 938 else 939 return RV(okrate); 940 #undef RV 941 } 942 943 static __inline int 944 match_id(const uint8_t *ie, const uint8_t *val, int len) 945 { 946 return (ie[1] == len && memcmp(ie+2, val, len) == 0); 947 } 948 949 static int 950 match_ssid(const uint8_t *ie, 951 int nssid, const struct ieee80211_scan_ssid ssids[]) 952 { 953 int i; 954 955 for (i = 0; i < nssid; i++) { 956 if (match_id(ie, ssids[i].ssid, ssids[i].len)) 957 return 1; 958 } 959 return 0; 960 } 961 962 #ifdef IEEE80211_SUPPORT_TDMA 963 static int 964 tdma_isfull(const struct ieee80211_tdma_param *tdma) 965 { 966 int slot, slotcnt; 967 968 slotcnt = tdma->tdma_slotcnt; 969 for (slot = slotcnt-1; slot >= 0; slot--) 970 if (isclr(tdma->tdma_inuse, slot)) 971 return 0; 972 return 1; 973 } 974 #endif /* IEEE80211_SUPPORT_TDMA */ 975 976 /* 977 * Test a scan candidate for suitability/compatibility. 978 */ 979 static int 980 match_bss(struct ieee80211vap *vap, 981 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 982 int debug) 983 { 984 struct ieee80211com *ic = vap->iv_ic; 985 struct ieee80211_scan_entry *se = &se0->base; 986 uint8_t rate; 987 int fail; 988 989 fail = 0; 990 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 991 fail |= MATCH_CHANNEL; 992 /* 993 * NB: normally the desired mode is used to construct 994 * the channel list, but it's possible for the scan 995 * cache to include entries for stations outside this 996 * list so we check the desired mode here to weed them 997 * out. 998 */ 999 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 1000 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 1001 chanflags[vap->iv_des_mode]) 1002 fail |= MATCH_CHANNEL; 1003 if (vap->iv_opmode == IEEE80211_M_IBSS) { 1004 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 1005 fail |= MATCH_CAPINFO; 1006 #ifdef IEEE80211_SUPPORT_TDMA 1007 } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { 1008 /* 1009 * Adhoc demo network setup shouldn't really be scanning 1010 * but just in case skip stations operating in IBSS or 1011 * BSS mode. 1012 */ 1013 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1014 fail |= MATCH_CAPINFO; 1015 /* 1016 * TDMA operation cannot coexist with a normal 802.11 network; 1017 * skip if IBSS or ESS capabilities are marked and require 1018 * the beacon have a TDMA ie present. 1019 */ 1020 if (vap->iv_caps & IEEE80211_C_TDMA) { 1021 const struct ieee80211_tdma_param *tdma = 1022 (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; 1023 const struct ieee80211_tdma_state *ts = vap->iv_tdma; 1024 1025 if (tdma == NULL) 1026 fail |= MATCH_TDMA_NOIE; 1027 else if (tdma->tdma_version != ts->tdma_version) 1028 fail |= MATCH_TDMA_VERSION; 1029 else if (tdma->tdma_slot != 0) 1030 fail |= MATCH_TDMA_NOTMASTER; 1031 else if (tdma_isfull(tdma)) 1032 fail |= MATCH_TDMA_NOSLOT; 1033 #if 0 1034 else if (ieee80211_local_address(se->se_macaddr)) 1035 fail |= MATCH_TDMA_LOCAL; 1036 #endif 1037 } 1038 #endif /* IEEE80211_SUPPORT_TDMA */ 1039 #ifdef IEEE80211_SUPPORT_MESH 1040 } else if (vap->iv_opmode == IEEE80211_M_MBSS) { 1041 const struct ieee80211_mesh_state *ms = vap->iv_mesh; 1042 /* 1043 * Mesh nodes have IBSS & ESS bits in capinfo turned off 1044 * and two special ie's that must be present. 1045 */ 1046 if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) 1047 fail |= MATCH_CAPINFO; 1048 else if (se->se_meshid[0] != IEEE80211_ELEMID_MESHID) 1049 fail |= MATCH_MESH_NOID; 1050 else if (ms->ms_idlen != 0 && 1051 match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) 1052 fail |= MATCH_MESHID; 1053 #endif 1054 } else { 1055 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 1056 fail |= MATCH_CAPINFO; 1057 /* 1058 * If 11d is enabled and we're attempting to join a bss 1059 * that advertises it's country code then compare our 1060 * current settings to what we fetched from the country ie. 1061 * If our country code is unspecified or different then do 1062 * not attempt to join the bss. We should have already 1063 * dispatched an event to user space that identifies the 1064 * new country code so our regdomain config should match. 1065 */ 1066 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 1067 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 1068 se->se_cc[0] != 0 && 1069 (ic->ic_regdomain.country == CTRY_DEFAULT || 1070 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 1071 fail |= MATCH_CC; 1072 } 1073 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 1074 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 1075 fail |= MATCH_PRIVACY; 1076 } else { 1077 /* XXX does this mean privacy is supported or required? */ 1078 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 1079 fail |= MATCH_PRIVACY; 1080 } 1081 se0->se_flags &= ~STA_DEMOTE11B; 1082 rate = check_rate(vap, se->se_chan, se); 1083 if (rate & IEEE80211_RATE_BASIC) { 1084 fail |= MATCH_RATE; 1085 /* 1086 * An 11b-only ap will give a rate mismatch if there is an 1087 * OFDM fixed tx rate for 11g. Try downgrading the channel 1088 * in the scan list to 11b and retry the rate check. 1089 */ 1090 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 1091 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 1092 if ((rate & IEEE80211_RATE_BASIC) == 0) { 1093 fail &= ~MATCH_RATE; 1094 se0->se_flags |= STA_DEMOTE11B; 1095 } 1096 } 1097 } else if (rate < 2*24) { 1098 /* 1099 * This is an 11b-only ap. Check the desired mode in 1100 * case that needs to be honored (mode 11g filters out 1101 * 11b-only ap's). Otherwise force any 11g channel used 1102 * in scanning to be demoted. 1103 * 1104 * NB: we cheat a bit here by looking at the max rate; 1105 * we could/should check the rates. 1106 */ 1107 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 1108 vap->iv_des_mode == IEEE80211_MODE_11B)) 1109 fail |= MATCH_RATE; 1110 else 1111 se0->se_flags |= STA_DEMOTE11B; 1112 } 1113 if (ss->ss_nssid != 0 && 1114 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 1115 fail |= MATCH_SSID; 1116 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 1117 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 1118 fail |= MATCH_BSSID; 1119 if (se0->se_fails >= STA_FAILS_MAX) 1120 fail |= MATCH_FAILS; 1121 if (se0->se_notseen >= STA_PURGE_SCANS) 1122 fail |= MATCH_NOTSEEN; 1123 if (se->se_rssi < STA_RSSI_MIN) 1124 fail |= MATCH_RSSI; 1125 #ifdef IEEE80211_DEBUG 1126 if (ieee80211_msg(vap, debug)) { 1127 kprintf(" %c %s", 1128 fail & MATCH_FAILS ? '=' : 1129 fail & MATCH_NOTSEEN ? '^' : 1130 fail & MATCH_CC ? '$' : 1131 #ifdef IEEE80211_SUPPORT_TDMA 1132 fail & MATCH_TDMA_NOIE ? '&' : 1133 fail & MATCH_TDMA_VERSION ? 'v' : 1134 fail & MATCH_TDMA_NOTMASTER ? 's' : 1135 fail & MATCH_TDMA_NOSLOT ? 'f' : 1136 fail & MATCH_TDMA_LOCAL ? 'l' : 1137 #endif 1138 fail & MATCH_MESH_NOID ? 'm' : 1139 fail ? '-' : '+', ether_sprintf(se->se_macaddr)); 1140 kprintf(" %s%c", ether_sprintf(se->se_bssid), 1141 fail & MATCH_BSSID ? '!' : ' '); 1142 kprintf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 1143 fail & MATCH_CHANNEL ? '!' : ' '); 1144 kprintf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 1145 kprintf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 1146 fail & MATCH_RATE ? '!' : ' '); 1147 kprintf(" %4s%c", 1148 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 1149 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", 1150 fail & MATCH_CAPINFO ? '!' : ' '); 1151 kprintf(" %3s%c ", 1152 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 1153 "wep" : "no", 1154 fail & MATCH_PRIVACY ? '!' : ' '); 1155 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 1156 kprintf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); 1157 } 1158 #endif 1159 return fail; 1160 } 1161 1162 static void 1163 sta_update_notseen(struct sta_table *st) 1164 { 1165 struct sta_entry *se; 1166 1167 IEEE80211_SCAN_TABLE_LOCK(st); 1168 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1169 /* 1170 * If seen the reset and don't bump the count; 1171 * otherwise bump the ``not seen'' count. Note 1172 * that this insures that stations for which we 1173 * see frames while not scanning but not during 1174 * this scan will not be penalized. 1175 */ 1176 if (se->se_seen) 1177 se->se_seen = 0; 1178 else 1179 se->se_notseen++; 1180 } 1181 IEEE80211_SCAN_TABLE_UNLOCK(st); 1182 } 1183 1184 static void 1185 sta_dec_fails(struct sta_table *st) 1186 { 1187 struct sta_entry *se; 1188 1189 IEEE80211_SCAN_TABLE_LOCK(st); 1190 TAILQ_FOREACH(se, &st->st_entry, se_list) 1191 if (se->se_fails) 1192 se->se_fails--; 1193 IEEE80211_SCAN_TABLE_UNLOCK(st); 1194 } 1195 1196 static struct sta_entry * 1197 select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1198 { 1199 struct sta_table *st = ss->ss_priv; 1200 struct sta_entry *se, *selbs = NULL; 1201 1202 IEEE80211_DPRINTF(vap, debug, " %s\n", 1203 "macaddr bssid chan rssi rate flag wep essid"); 1204 IEEE80211_SCAN_TABLE_LOCK(st); 1205 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1206 ieee80211_ies_expand(&se->base.se_ies); 1207 if (match_bss(vap, ss, se, debug) == 0) { 1208 if (selbs == NULL) 1209 selbs = se; 1210 else if (sta_compare(se, selbs) > 0) 1211 selbs = se; 1212 } 1213 } 1214 IEEE80211_SCAN_TABLE_UNLOCK(st); 1215 1216 return selbs; 1217 } 1218 1219 /* 1220 * Pick an ap or ibss network to join or find a channel 1221 * to use to start an ibss network. 1222 */ 1223 static int 1224 sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1225 { 1226 struct sta_table *st = ss->ss_priv; 1227 struct sta_entry *selbs; 1228 struct ieee80211_channel *chan; 1229 1230 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1231 ("wrong mode %u", vap->iv_opmode)); 1232 1233 if (st->st_newscan) { 1234 sta_update_notseen(st); 1235 st->st_newscan = 0; 1236 } 1237 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1238 /* 1239 * Manual/background scan, don't select+join the 1240 * bss, just return. The scanning framework will 1241 * handle notification that this has completed. 1242 */ 1243 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1244 return 1; 1245 } 1246 /* 1247 * Automatic sequencing; look for a candidate and 1248 * if found join the network. 1249 */ 1250 /* NB: unlocked read should be ok */ 1251 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1252 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1253 "%s: no scan candidate\n", __func__); 1254 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1255 return 0; 1256 notfound: 1257 /* 1258 * If nothing suitable was found decrement 1259 * the failure counts so entries will be 1260 * reconsidered the next time around. We 1261 * really want to do this only for sta's 1262 * where we've previously had some success. 1263 */ 1264 sta_dec_fails(st); 1265 st->st_newscan = 1; 1266 return 0; /* restart scan */ 1267 } 1268 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1269 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1270 return (selbs != NULL); 1271 if (selbs == NULL) 1272 goto notfound; 1273 chan = selbs->base.se_chan; 1274 if (selbs->se_flags & STA_DEMOTE11B) 1275 chan = demote11b(vap, chan); 1276 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1277 goto notfound; 1278 return 1; /* terminate scan */ 1279 } 1280 1281 /* 1282 * Lookup an entry in the scan cache. We assume we're 1283 * called from the bottom half or such that we don't need 1284 * to block the bottom half so that it's safe to return 1285 * a reference to an entry w/o holding the lock on the table. 1286 */ 1287 static struct sta_entry * 1288 sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1289 { 1290 struct sta_entry *se; 1291 int hash = STA_HASH(macaddr); 1292 1293 IEEE80211_SCAN_TABLE_LOCK(st); 1294 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1295 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1296 break; 1297 IEEE80211_SCAN_TABLE_UNLOCK(st); 1298 1299 return se; /* NB: unlocked */ 1300 } 1301 1302 static void 1303 sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1304 { 1305 struct ieee80211com *ic = vap->iv_ic; 1306 struct ieee80211_node *ni = vap->iv_bss; 1307 struct sta_table *st = ss->ss_priv; 1308 enum ieee80211_phymode mode; 1309 struct sta_entry *se, *selbs; 1310 uint8_t roamRate, curRate, ucastRate; 1311 int8_t roamRssi, curRssi; 1312 1313 se = sta_lookup(st, ni->ni_macaddr); 1314 if (se == NULL) { 1315 /* XXX something is wrong */ 1316 return; 1317 } 1318 1319 mode = ieee80211_chan2mode(ic->ic_bsschan); 1320 roamRate = vap->iv_roamparms[mode].rate; 1321 roamRssi = vap->iv_roamparms[mode].rssi; 1322 ucastRate = vap->iv_txparms[mode].ucastrate; 1323 /* NB: the most up to date rssi is in the node, not the scan cache */ 1324 curRssi = ic->ic_node_getrssi(ni); 1325 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1326 curRate = ni->ni_txrate; 1327 roamRate &= IEEE80211_RATE_VAL; 1328 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1329 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1330 __func__, curRssi, curRate, roamRssi, roamRate); 1331 } else { 1332 curRate = roamRate; /* NB: insure compare below fails */ 1333 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1334 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1335 } 1336 /* 1337 * Check if a new ap should be used and switch. 1338 * XXX deauth current ap 1339 */ 1340 if (curRate < roamRate || curRssi < roamRssi) { 1341 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1342 /* 1343 * Scan cache contents are too old; force a scan now 1344 * if possible so we have current state to make a 1345 * decision with. We don't kick off a bg scan if 1346 * we're using dynamic turbo and boosted or if the 1347 * channel is busy. 1348 * XXX force immediate switch on scan complete 1349 */ 1350 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1351 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) 1352 ieee80211_bg_scan(vap, 0); 1353 return; 1354 } 1355 se->base.se_rssi = curRssi; 1356 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1357 if (selbs != NULL && selbs != se) { 1358 struct ieee80211_channel *chan; 1359 1360 IEEE80211_DPRINTF(vap, 1361 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1362 "%s: ROAM: curRate %u, roamRate %u, " 1363 "curRssi %d, roamRssi %d\n", __func__, 1364 curRate, roamRate, curRssi, roamRssi); 1365 1366 chan = selbs->base.se_chan; 1367 if (selbs->se_flags & STA_DEMOTE11B) 1368 chan = demote11b(vap, chan); 1369 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1370 } 1371 } 1372 } 1373 1374 /* 1375 * Age entries in the scan cache. 1376 * XXX also do roaming since it's convenient 1377 */ 1378 static void 1379 sta_age(struct ieee80211_scan_state *ss) 1380 { 1381 struct ieee80211vap *vap = ss->ss_vap; 1382 1383 adhoc_age(ss); 1384 /* 1385 * If rate control is enabled check periodically to see if 1386 * we should roam from our current connection to one that 1387 * might be better. This only applies when we're operating 1388 * in sta mode and automatic roaming is set. 1389 * XXX defer if busy 1390 * XXX repeater station 1391 * XXX do when !bgscan? 1392 */ 1393 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1394 ("wrong mode %u", vap->iv_opmode)); 1395 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1396 (vap->iv_flags & IEEE80211_F_BGSCAN) && 1397 vap->iv_state >= IEEE80211_S_RUN) 1398 /* XXX vap is implicit */ 1399 sta_roam_check(ss, vap); 1400 } 1401 1402 /* 1403 * Iterate over the entries in the scan cache, invoking 1404 * the callback function on each one. 1405 */ 1406 static void 1407 sta_iterate(struct ieee80211_scan_state *ss, 1408 ieee80211_scan_iter_func *f, void *arg) 1409 { 1410 struct sta_table *st = ss->ss_priv; 1411 struct sta_entry *se; 1412 u_int gen; 1413 1414 #if defined(__DragonFly__) 1415 lockmgr(&st->st_scanlock, LK_EXCLUSIVE); 1416 #else 1417 mtx_lock(&st->st_scanlock); 1418 #endif 1419 gen = st->st_scaniter++; 1420 restart: 1421 IEEE80211_SCAN_TABLE_LOCK(st); 1422 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1423 if (se->se_scangen != gen) { 1424 se->se_scangen = gen; 1425 /* update public state */ 1426 se->base.se_age = ticks - se->se_lastupdate; 1427 IEEE80211_SCAN_TABLE_UNLOCK(st); 1428 (*f)(arg, &se->base); 1429 goto restart; 1430 } 1431 } 1432 IEEE80211_SCAN_TABLE_UNLOCK(st); 1433 1434 #if defined(__DragonFly__) 1435 lockmgr(&st->st_scanlock, LK_RELEASE); 1436 #else 1437 mtx_unlock(&st->st_scanlock); 1438 #endif 1439 } 1440 1441 static void 1442 sta_assoc_fail(struct ieee80211_scan_state *ss, 1443 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1444 { 1445 struct sta_table *st = ss->ss_priv; 1446 struct sta_entry *se; 1447 1448 se = sta_lookup(st, macaddr); 1449 if (se != NULL) { 1450 se->se_fails++; 1451 se->se_lastfail = ticks; 1452 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1453 macaddr, "%s: reason %u fails %u", 1454 __func__, reason, se->se_fails); 1455 } 1456 } 1457 1458 static void 1459 sta_assoc_success(struct ieee80211_scan_state *ss, 1460 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1461 { 1462 struct sta_table *st = ss->ss_priv; 1463 struct sta_entry *se; 1464 1465 se = sta_lookup(st, macaddr); 1466 if (se != NULL) { 1467 #if 0 1468 se->se_fails = 0; 1469 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1470 macaddr, "%s: fails %u", 1471 __func__, se->se_fails); 1472 #endif 1473 se->se_lastassoc = ticks; 1474 } 1475 } 1476 1477 static const struct ieee80211_scanner sta_default = { 1478 .scan_name = "default", 1479 .scan_attach = sta_attach, 1480 .scan_detach = sta_detach, 1481 .scan_start = sta_start, 1482 .scan_restart = sta_restart, 1483 .scan_cancel = sta_cancel, 1484 .scan_end = sta_pick_bss, 1485 .scan_flush = sta_flush, 1486 .scan_add = sta_add, 1487 .scan_age = sta_age, 1488 .scan_iterate = sta_iterate, 1489 .scan_assoc_fail = sta_assoc_fail, 1490 .scan_assoc_success = sta_assoc_success, 1491 }; 1492 IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); 1493 1494 /* 1495 * Adhoc mode-specific support. 1496 */ 1497 1498 static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1499 { 5180, 5200, 5220, 5240 }; 1500 static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1501 { 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1502 static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1503 { 5170, 5190, 5210, 5230 }; 1504 static const uint16_t adhoc11b[] = /* 10, 11 */ 1505 { 2457, 2462 }; 1506 1507 static const struct scanlist adhocScanTable[] = { 1508 { IEEE80211_MODE_11B, X(adhoc11b) }, 1509 { IEEE80211_MODE_11A, X(adhocWorld) }, 1510 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1511 { IEEE80211_MODE_11B, X(adhocMkk) }, 1512 { .list = NULL } 1513 }; 1514 #undef X 1515 1516 /* 1517 * Start an adhoc-mode scan by populating the channel list. 1518 */ 1519 static int 1520 adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1521 { 1522 struct sta_table *st = ss->ss_priv; 1523 1524 makescanlist(ss, vap, adhocScanTable); 1525 1526 if (ss->ss_mindwell == 0) 1527 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1528 if (ss->ss_maxdwell == 0) 1529 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1530 1531 st->st_scangen++; 1532 st->st_newscan = 1; 1533 1534 return 0; 1535 } 1536 1537 /* 1538 * Select a channel to start an adhoc network on. 1539 * The channel list was populated with appropriate 1540 * channels so select one that looks least occupied. 1541 */ 1542 static struct ieee80211_channel * 1543 adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1544 { 1545 struct sta_table *st = ss->ss_priv; 1546 struct sta_entry *se; 1547 struct ieee80211_channel *c, *bestchan; 1548 int i, bestrssi, maxrssi; 1549 1550 bestchan = NULL; 1551 bestrssi = -1; 1552 1553 IEEE80211_SCAN_TABLE_LOCK(st); 1554 for (i = 0; i < ss->ss_last; i++) { 1555 c = ss->ss_chans[i]; 1556 /* never consider a channel with radar */ 1557 if (IEEE80211_IS_CHAN_RADAR(c)) 1558 continue; 1559 /* skip channels disallowed by regulatory settings */ 1560 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1561 continue; 1562 /* check channel attributes for band compatibility */ 1563 if (flags != 0 && (c->ic_flags & flags) != flags) 1564 continue; 1565 maxrssi = 0; 1566 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1567 if (se->base.se_chan != c) 1568 continue; 1569 if (se->base.se_rssi > maxrssi) 1570 maxrssi = se->base.se_rssi; 1571 } 1572 if (bestchan == NULL || maxrssi < bestrssi) 1573 bestchan = c; 1574 } 1575 IEEE80211_SCAN_TABLE_UNLOCK(st); 1576 1577 return bestchan; 1578 } 1579 1580 /* 1581 * Pick an ibss network to join or find a channel 1582 * to use to start an ibss network. 1583 */ 1584 static int 1585 adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1586 { 1587 struct sta_table *st = ss->ss_priv; 1588 struct sta_entry *selbs; 1589 struct ieee80211_channel *chan; 1590 struct ieee80211com *ic = vap->iv_ic; 1591 1592 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1593 vap->iv_opmode == IEEE80211_M_AHDEMO || 1594 vap->iv_opmode == IEEE80211_M_MBSS, 1595 ("wrong opmode %u", vap->iv_opmode)); 1596 1597 if (st->st_newscan) { 1598 sta_update_notseen(st); 1599 st->st_newscan = 0; 1600 } 1601 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1602 /* 1603 * Manual/background scan, don't select+join the 1604 * bss, just return. The scanning framework will 1605 * handle notification that this has completed. 1606 */ 1607 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1608 return 1; 1609 } 1610 /* 1611 * Automatic sequencing; look for a candidate and 1612 * if found join the network. 1613 */ 1614 /* NB: unlocked read should be ok */ 1615 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1616 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1617 "%s: no scan candidate\n", __func__); 1618 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1619 return 0; 1620 notfound: 1621 /* NB: never auto-start a tdma network for slot !0 */ 1622 #ifdef IEEE80211_SUPPORT_TDMA 1623 if (vap->iv_des_nssid && 1624 ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || 1625 ieee80211_tdma_getslot(vap) == 0)) { 1626 #else 1627 if (vap->iv_des_nssid) { 1628 #endif 1629 /* 1630 * No existing adhoc network to join and we have 1631 * an ssid; start one up. If no channel was 1632 * specified, try to select a channel. 1633 */ 1634 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1635 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1636 chan = adhoc_pick_channel(ss, 0); 1637 } else 1638 chan = vap->iv_des_chan; 1639 if (chan != NULL) { 1640 struct ieee80211com *ic = vap->iv_ic; 1641 /* 1642 * Create a HT capable IBSS; the per-node 1643 * probe request/response will result in 1644 * "correct" rate control capabilities being 1645 * negotiated. 1646 */ 1647 chan = ieee80211_ht_adjust_channel(ic, 1648 chan, vap->iv_flags_ht); 1649 ieee80211_create_ibss(vap, chan); 1650 return 1; 1651 } 1652 } 1653 /* 1654 * If nothing suitable was found decrement 1655 * the failure counts so entries will be 1656 * reconsidered the next time around. We 1657 * really want to do this only for sta's 1658 * where we've previously had some success. 1659 */ 1660 sta_dec_fails(st); 1661 st->st_newscan = 1; 1662 return 0; /* restart scan */ 1663 } 1664 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1665 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1666 return (selbs != NULL); 1667 if (selbs == NULL) 1668 goto notfound; 1669 chan = selbs->base.se_chan; 1670 if (selbs->se_flags & STA_DEMOTE11B) 1671 chan = demote11b(vap, chan); 1672 /* 1673 * If HT is available, make it a possibility here. 1674 * The intent is to enable HT20/HT40 when joining a non-HT 1675 * IBSS node; we can then advertise HT IEs and speak HT 1676 * to any subsequent nodes that support it. 1677 */ 1678 chan = ieee80211_ht_adjust_channel(ic, 1679 chan, vap->iv_flags_ht); 1680 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1681 goto notfound; 1682 return 1; /* terminate scan */ 1683 } 1684 1685 /* 1686 * Age entries in the scan cache. 1687 */ 1688 static void 1689 adhoc_age(struct ieee80211_scan_state *ss) 1690 { 1691 struct sta_table *st = ss->ss_priv; 1692 struct sta_entry *se, *next; 1693 1694 IEEE80211_SCAN_TABLE_LOCK(st); 1695 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 1696 if (se->se_notseen > STA_PURGE_SCANS) { 1697 TAILQ_REMOVE(&st->st_entry, se, se_list); 1698 LIST_REMOVE(se, se_hash); 1699 ieee80211_ies_cleanup(&se->base.se_ies); 1700 kfree(se, M_80211_SCAN); 1701 } 1702 } 1703 IEEE80211_SCAN_TABLE_UNLOCK(st); 1704 } 1705 1706 static const struct ieee80211_scanner adhoc_default = { 1707 .scan_name = "default", 1708 .scan_attach = sta_attach, 1709 .scan_detach = sta_detach, 1710 .scan_start = adhoc_start, 1711 .scan_restart = sta_restart, 1712 .scan_cancel = sta_cancel, 1713 .scan_end = adhoc_pick_bss, 1714 .scan_flush = sta_flush, 1715 .scan_pickchan = adhoc_pick_channel, 1716 .scan_add = sta_add, 1717 .scan_age = adhoc_age, 1718 .scan_iterate = sta_iterate, 1719 .scan_assoc_fail = sta_assoc_fail, 1720 .scan_assoc_success = sta_assoc_success, 1721 }; 1722 IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1723 IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1724 1725 static void 1726 ap_force_promisc(struct ieee80211com *ic) 1727 { 1728 struct ifnet *ifp = ic->ic_ifp; 1729 1730 IEEE80211_LOCK(ic); 1731 /* set interface into promiscuous mode */ 1732 ifp->if_flags |= IFF_PROMISC; 1733 ieee80211_runtask(ic, &ic->ic_promisc_task); 1734 IEEE80211_UNLOCK(ic); 1735 } 1736 1737 static void 1738 ap_reset_promisc(struct ieee80211com *ic) 1739 { 1740 IEEE80211_LOCK(ic); 1741 ieee80211_syncifflag_locked(ic, IFF_PROMISC); 1742 IEEE80211_UNLOCK(ic); 1743 } 1744 1745 static int 1746 ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1747 { 1748 struct sta_table *st = ss->ss_priv; 1749 1750 makescanlist(ss, vap, staScanTable); 1751 1752 if (ss->ss_mindwell == 0) 1753 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1754 if (ss->ss_maxdwell == 0) 1755 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1756 1757 st->st_scangen++; 1758 st->st_newscan = 1; 1759 1760 ap_force_promisc(vap->iv_ic); 1761 return 0; 1762 } 1763 1764 /* 1765 * Cancel an ongoing scan. 1766 */ 1767 static int 1768 ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1769 { 1770 ap_reset_promisc(vap->iv_ic); 1771 return 0; 1772 } 1773 1774 /* 1775 * Pick a quiet channel to use for ap operation. 1776 */ 1777 static struct ieee80211_channel * 1778 ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1779 { 1780 struct sta_table *st = ss->ss_priv; 1781 struct ieee80211_channel *bestchan = NULL; 1782 int i; 1783 1784 /* XXX select channel more intelligently, e.g. channel spread, power */ 1785 /* NB: use scan list order to preserve channel preference */ 1786 for (i = 0; i < ss->ss_last; i++) { 1787 struct ieee80211_channel *chan = ss->ss_chans[i]; 1788 /* 1789 * If the channel is unoccupied the max rssi 1790 * should be zero; just take it. Otherwise 1791 * track the channel with the lowest rssi and 1792 * use that when all channels appear occupied. 1793 */ 1794 if (IEEE80211_IS_CHAN_RADAR(chan)) 1795 continue; 1796 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1797 continue; 1798 /* check channel attributes for band compatibility */ 1799 if (flags != 0 && (chan->ic_flags & flags) != flags) 1800 continue; 1801 KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); 1802 /* XXX channel have interference */ 1803 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1804 /* XXX use other considerations */ 1805 return chan; 1806 } 1807 if (bestchan == NULL || 1808 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1809 bestchan = chan; 1810 } 1811 return bestchan; 1812 } 1813 1814 /* 1815 * Pick a quiet channel to use for ap operation. 1816 */ 1817 static int 1818 ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1819 { 1820 struct ieee80211com *ic = vap->iv_ic; 1821 struct ieee80211_channel *bestchan; 1822 1823 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1824 ("wrong opmode %u", vap->iv_opmode)); 1825 bestchan = ap_pick_channel(ss, 0); 1826 if (bestchan == NULL) { 1827 /* no suitable channel, should not happen */ 1828 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1829 "%s: no suitable channel! (should not happen)\n", __func__); 1830 /* XXX print something? */ 1831 return 0; /* restart scan */ 1832 } 1833 /* 1834 * If this is a dynamic turbo channel, start with the unboosted one. 1835 */ 1836 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1837 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1838 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1839 if (bestchan == NULL) { 1840 /* should never happen ?? */ 1841 return 0; 1842 } 1843 } 1844 ap_reset_promisc(ic); 1845 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1846 /* 1847 * Manual/background scan, don't select+join the 1848 * bss, just return. The scanning framework will 1849 * handle notification that this has completed. 1850 */ 1851 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1852 return 1; 1853 } 1854 ieee80211_create_ibss(vap, 1855 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht)); 1856 return 1; 1857 } 1858 1859 static const struct ieee80211_scanner ap_default = { 1860 .scan_name = "default", 1861 .scan_attach = sta_attach, 1862 .scan_detach = sta_detach, 1863 .scan_start = ap_start, 1864 .scan_restart = sta_restart, 1865 .scan_cancel = ap_cancel, 1866 .scan_end = ap_end, 1867 .scan_flush = sta_flush, 1868 .scan_pickchan = ap_pick_channel, 1869 .scan_add = sta_add, 1870 .scan_age = adhoc_age, 1871 .scan_iterate = sta_iterate, 1872 .scan_assoc_success = sta_assoc_success, 1873 .scan_assoc_fail = sta_assoc_fail, 1874 }; 1875 IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1876 1877 #ifdef IEEE80211_SUPPORT_MESH 1878 /* 1879 * Pick an mbss network to join or find a channel 1880 * to use to start an mbss network. 1881 */ 1882 static int 1883 mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1884 { 1885 struct sta_table *st = ss->ss_priv; 1886 struct ieee80211_mesh_state *ms = vap->iv_mesh; 1887 struct sta_entry *selbs; 1888 struct ieee80211_channel *chan; 1889 1890 KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, 1891 ("wrong opmode %u", vap->iv_opmode)); 1892 1893 if (st->st_newscan) { 1894 sta_update_notseen(st); 1895 st->st_newscan = 0; 1896 } 1897 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1898 /* 1899 * Manual/background scan, don't select+join the 1900 * bss, just return. The scanning framework will 1901 * handle notification that this has completed. 1902 */ 1903 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1904 return 1; 1905 } 1906 /* 1907 * Automatic sequencing; look for a candidate and 1908 * if found join the network. 1909 */ 1910 /* NB: unlocked read should be ok */ 1911 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1912 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1913 "%s: no scan candidate\n", __func__); 1914 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1915 return 0; 1916 notfound: 1917 if (ms->ms_idlen != 0) { 1918 /* 1919 * No existing mbss network to join and we have 1920 * a meshid; start one up. If no channel was 1921 * specified, try to select a channel. 1922 */ 1923 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1924 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1925 struct ieee80211com *ic = vap->iv_ic; 1926 1927 chan = adhoc_pick_channel(ss, 0); 1928 if (chan != NULL) 1929 chan = ieee80211_ht_adjust_channel(ic, 1930 chan, vap->iv_flags_ht); 1931 } else 1932 chan = vap->iv_des_chan; 1933 if (chan != NULL) { 1934 ieee80211_create_ibss(vap, chan); 1935 return 1; 1936 } 1937 } 1938 /* 1939 * If nothing suitable was found decrement 1940 * the failure counts so entries will be 1941 * reconsidered the next time around. We 1942 * really want to do this only for sta's 1943 * where we've previously had some success. 1944 */ 1945 sta_dec_fails(st); 1946 st->st_newscan = 1; 1947 return 0; /* restart scan */ 1948 } 1949 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1950 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1951 return (selbs != NULL); 1952 if (selbs == NULL) 1953 goto notfound; 1954 chan = selbs->base.se_chan; 1955 if (selbs->se_flags & STA_DEMOTE11B) 1956 chan = demote11b(vap, chan); 1957 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1958 goto notfound; 1959 return 1; /* terminate scan */ 1960 } 1961 1962 static const struct ieee80211_scanner mesh_default = { 1963 .scan_name = "default", 1964 .scan_attach = sta_attach, 1965 .scan_detach = sta_detach, 1966 .scan_start = adhoc_start, 1967 .scan_restart = sta_restart, 1968 .scan_cancel = sta_cancel, 1969 .scan_end = mesh_pick_bss, 1970 .scan_flush = sta_flush, 1971 .scan_pickchan = adhoc_pick_channel, 1972 .scan_add = sta_add, 1973 .scan_age = adhoc_age, 1974 .scan_iterate = sta_iterate, 1975 .scan_assoc_fail = sta_assoc_fail, 1976 .scan_assoc_success = sta_assoc_success, 1977 }; 1978 IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); 1979 #endif /* IEEE80211_SUPPORT_MESH */ 1980