ieee80211_scan_sta.c revision 184302
1/*- 2 * Copyright (c) 2002-2008 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: head/sys/net80211/ieee80211_scan_sta.c 184302 2008-10-26 21:56:27Z sam $"); 28 29/* 30 * IEEE 802.11 station scanning support. 31 */ 32#include "opt_wlan.h" 33 34#include <sys/param.h> 35#include <sys/systm.h> 36#include <sys/kernel.h> 37#include <sys/module.h> 38 39#include <sys/socket.h> 40 41#include <net/if.h> 42#include <net/if_media.h> 43#include <net/ethernet.h> 44 45#include <net80211/ieee80211_var.h> 46#include <net80211/ieee80211_input.h> 47#include <net80211/ieee80211_regdomain.h> 48 49#include <net/bpf.h> 50 51/* 52 * Parameters for managing cache entries: 53 * 54 * o a station with STA_FAILS_MAX failures is not considered 55 * when picking a candidate 56 * o a station that hasn't had an update in STA_PURGE_SCANS 57 * (background) scans is discarded 58 * o after STA_FAILS_AGE seconds we clear the failure count 59 */ 60#define STA_FAILS_MAX 2 /* assoc failures before ignored */ 61#define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ 62#define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ 63 64/* XXX tunable */ 65#define STA_RSSI_MIN 8 /* min acceptable rssi */ 66#define STA_RSSI_MAX 40 /* max rssi for comparison */ 67 68struct sta_entry { 69 struct ieee80211_scan_entry base; 70 TAILQ_ENTRY(sta_entry) se_list; 71 LIST_ENTRY(sta_entry) se_hash; 72 uint8_t se_fails; /* failure to associate count */ 73 uint8_t se_seen; /* seen during current scan */ 74 uint8_t se_notseen; /* not seen in previous scans */ 75 uint8_t se_flags; 76#define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ 77 uint32_t se_avgrssi; /* LPF rssi state */ 78 unsigned long se_lastupdate; /* time of last update */ 79 unsigned long se_lastfail; /* time of last failure */ 80 unsigned long se_lastassoc; /* time of last association */ 81 u_int se_scangen; /* iterator scan gen# */ 82 u_int se_countrygen; /* gen# of last cc notify */ 83}; 84 85#define STA_HASHSIZE 32 86/* simple hash is enough for variation of macaddr */ 87#define STA_HASH(addr) \ 88 (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) 89 90struct sta_table { 91 struct mtx st_lock; /* on scan table */ 92 TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ 93 LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; 94 struct mtx st_scanlock; /* on st_scaniter */ 95 u_int st_scaniter; /* gen# for iterator */ 96 u_int st_scangen; /* scan generation # */ 97 int st_newscan; 98 /* ap-related state */ 99 int st_maxrssi[IEEE80211_CHAN_MAX]; 100}; 101 102static void sta_flush_table(struct sta_table *); 103/* 104 * match_bss returns a bitmask describing if an entry is suitable 105 * for use. If non-zero the entry was deemed not suitable and it's 106 * contents explains why. The following flags are or'd to to this 107 * mask and can be used to figure out why the entry was rejected. 108 */ 109#define MATCH_CHANNEL 0x0001 /* channel mismatch */ 110#define MATCH_CAPINFO 0x0002 /* capabilities mismatch, e.g. no ess */ 111#define MATCH_PRIVACY 0x0004 /* privacy mismatch */ 112#define MATCH_RATE 0x0008 /* rate set mismatch */ 113#define MATCH_SSID 0x0010 /* ssid mismatch */ 114#define MATCH_BSSID 0x0020 /* bssid mismatch */ 115#define MATCH_FAILS 0x0040 /* too many failed auth attempts */ 116#define MATCH_NOTSEEN 0x0080 /* not seen in recent scans */ 117#define MATCH_RSSI 0x0100 /* rssi deemed too low to use */ 118#define MATCH_CC 0x0200 /* country code mismatch */ 119static int match_bss(struct ieee80211vap *, 120 const struct ieee80211_scan_state *, struct sta_entry *, int); 121static void adhoc_age(struct ieee80211_scan_state *); 122 123static __inline int 124isocmp(const uint8_t cc1[], const uint8_t cc2[]) 125{ 126 return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); 127} 128 129/* number of references from net80211 layer */ 130static int nrefs = 0; 131 132/* 133 * Attach prior to any scanning work. 134 */ 135static int 136sta_attach(struct ieee80211_scan_state *ss) 137{ 138 struct sta_table *st; 139 140 MALLOC(st, struct sta_table *, sizeof(struct sta_table), 141 M_80211_SCAN, M_NOWAIT | M_ZERO); 142 if (st == NULL) 143 return 0; 144 mtx_init(&st->st_lock, "scantable", "802.11 scan table", MTX_DEF); 145 mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF); 146 TAILQ_INIT(&st->st_entry); 147 ss->ss_priv = st; 148 nrefs++; /* NB: we assume caller locking */ 149 return 1; 150} 151 152/* 153 * Cleanup any private state. 154 */ 155static int 156sta_detach(struct ieee80211_scan_state *ss) 157{ 158 struct sta_table *st = ss->ss_priv; 159 160 if (st != NULL) { 161 sta_flush_table(st); 162 mtx_destroy(&st->st_lock); 163 mtx_destroy(&st->st_scanlock); 164 FREE(st, M_80211_SCAN); 165 KASSERT(nrefs > 0, ("imbalanced attach/detach")); 166 nrefs--; /* NB: we assume caller locking */ 167 } 168 return 1; 169} 170 171/* 172 * Flush all per-scan state. 173 */ 174static int 175sta_flush(struct ieee80211_scan_state *ss) 176{ 177 struct sta_table *st = ss->ss_priv; 178 179 mtx_lock(&st->st_lock); 180 sta_flush_table(st); 181 mtx_unlock(&st->st_lock); 182 ss->ss_last = 0; 183 return 0; 184} 185 186/* 187 * Flush all entries in the scan cache. 188 */ 189static void 190sta_flush_table(struct sta_table *st) 191{ 192 struct sta_entry *se, *next; 193 194 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 195 TAILQ_REMOVE(&st->st_entry, se, se_list); 196 LIST_REMOVE(se, se_hash); 197 ieee80211_ies_cleanup(&se->base.se_ies); 198 FREE(se, M_80211_SCAN); 199 } 200 memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); 201} 202 203/* 204 * Process a beacon or probe response frame; create an 205 * entry in the scan cache or update any previous entry. 206 */ 207static int 208sta_add(struct ieee80211_scan_state *ss, 209 const struct ieee80211_scanparams *sp, 210 const struct ieee80211_frame *wh, 211 int subtype, int rssi, int noise, int rstamp) 212{ 213#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) 214#define PICK1ST(_ss) \ 215 ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ 216 IEEE80211_SCAN_PICK1ST) 217 struct sta_table *st = ss->ss_priv; 218 const uint8_t *macaddr = wh->i_addr2; 219 struct ieee80211vap *vap = ss->ss_vap; 220 struct ieee80211com *ic = vap->iv_ic; 221 struct sta_entry *se; 222 struct ieee80211_scan_entry *ise; 223 int hash; 224 225 hash = STA_HASH(macaddr); 226 227 mtx_lock(&st->st_lock); 228 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 229 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 230 goto found; 231 MALLOC(se, struct sta_entry *, sizeof(struct sta_entry), 232 M_80211_SCAN, M_NOWAIT | M_ZERO); 233 if (se == NULL) { 234 mtx_unlock(&st->st_lock); 235 return 0; 236 } 237 se->se_scangen = st->st_scaniter-1; 238 se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; 239 IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); 240 TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); 241 LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); 242found: 243 ise = &se->base; 244 /* XXX ap beaconing multiple ssid w/ same bssid */ 245 if (sp->ssid[1] != 0 && 246 (ISPROBE(subtype) || ise->se_ssid[1] == 0)) 247 memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); 248 KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, 249 ("rate set too large: %u", sp->rates[1])); 250 memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); 251 if (sp->xrates != NULL) { 252 /* XXX validate xrates[1] */ 253 KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, 254 ("xrate set too large: %u", sp->xrates[1])); 255 memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); 256 } else 257 ise->se_xrates[1] = 0; 258 IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); 259 if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { 260 /* 261 * Record rssi data using extended precision LPF filter. 262 * 263 * NB: use only on-channel data to insure we get a good 264 * estimate of the signal we'll see when associated. 265 */ 266 IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); 267 ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); 268 ise->se_noise = noise; 269 } 270 ise->se_rstamp = rstamp; 271 memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); 272 ise->se_intval = sp->bintval; 273 ise->se_capinfo = sp->capinfo; 274 /* 275 * Beware of overriding se_chan for frames seen 276 * off-channel; this can cause us to attempt an 277 * association on the wrong channel. 278 */ 279 if (sp->status & IEEE80211_BPARSE_OFFCHAN) { 280 struct ieee80211_channel *c; 281 /* 282 * Off-channel, locate the home/bss channel for the sta 283 * using the value broadcast in the DSPARMS ie. We know 284 * sp->chan has this value because it's used to calculate 285 * IEEE80211_BPARSE_OFFCHAN. 286 */ 287 c = ieee80211_find_channel_byieee(ic, sp->chan, 288 ic->ic_curchan->ic_flags); 289 if (c != NULL) { 290 ise->se_chan = c; 291 } else if (ise->se_chan == NULL) { 292 /* should not happen, pick something */ 293 ise->se_chan = ic->ic_curchan; 294 } 295 } else 296 ise->se_chan = ic->ic_curchan; 297 ise->se_fhdwell = sp->fhdwell; 298 ise->se_fhindex = sp->fhindex; 299 ise->se_erp = sp->erp; 300 ise->se_timoff = sp->timoff; 301 if (sp->tim != NULL) { 302 const struct ieee80211_tim_ie *tim = 303 (const struct ieee80211_tim_ie *) sp->tim; 304 ise->se_dtimperiod = tim->tim_period; 305 } 306 if (sp->country != NULL) { 307 const struct ieee80211_country_ie *cie = 308 (const struct ieee80211_country_ie *) sp->country; 309 /* 310 * If 11d is enabled and we're attempting to join a bss 311 * that advertises it's country code then compare our 312 * current settings to what we fetched from the country ie. 313 * If our country code is unspecified or different then 314 * dispatch an event to user space that identifies the 315 * country code so our regdomain config can be changed. 316 */ 317 /* XXX only for STA mode? */ 318 if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || 319 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 320 (ic->ic_regdomain.country == CTRY_DEFAULT || 321 !isocmp(cie->cc, ic->ic_regdomain.isocc))) { 322 /* only issue one notify event per scan */ 323 if (se->se_countrygen != st->st_scangen) { 324 ieee80211_notify_country(vap, ise->se_bssid, 325 cie->cc); 326 se->se_countrygen = st->st_scangen; 327 } 328 } 329 ise->se_cc[0] = cie->cc[0]; 330 ise->se_cc[1] = cie->cc[1]; 331 } 332 /* NB: no need to setup ie ptrs; they are not (currently) used */ 333 (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); 334 335 /* clear failure count after STA_FAIL_AGE passes */ 336 if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { 337 se->se_fails = 0; 338 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, 339 "%s: fails %u", __func__, se->se_fails); 340 } 341 342 se->se_lastupdate = ticks; /* update time */ 343 se->se_seen = 1; 344 se->se_notseen = 0; 345 346 if (rssi > st->st_maxrssi[sp->bchan]) 347 st->st_maxrssi[sp->bchan] = rssi; 348 349 mtx_unlock(&st->st_lock); 350 351 /* 352 * If looking for a quick choice and nothing's 353 * been found check here. 354 */ 355 if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) 356 ss->ss_flags |= IEEE80211_SCAN_GOTPICK; 357 358 return 1; 359#undef PICK1ST 360#undef ISPROBE 361} 362 363/* 364 * Check if a channel is excluded by user request. 365 */ 366static int 367isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) 368{ 369 return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || 370 (vap->iv_des_chan != IEEE80211_CHAN_ANYC && 371 c->ic_freq != vap->iv_des_chan->ic_freq)); 372} 373 374static struct ieee80211_channel * 375find11gchannel(struct ieee80211com *ic, int i, int freq) 376{ 377 struct ieee80211_channel *c; 378 int j; 379 380 /* 381 * The normal ordering in the channel list is b channel 382 * immediately followed by g so optimize the search for 383 * this. We'll still do a full search just in case. 384 */ 385 for (j = i+1; j < ic->ic_nchans; j++) { 386 c = &ic->ic_channels[j]; 387 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c)) 388 return c; 389 } 390 for (j = 0; j < i; j++) { 391 c = &ic->ic_channels[j]; 392 if (c->ic_freq == freq && IEEE80211_IS_CHAN_ANYG(c)) 393 return c; 394 } 395 return NULL; 396} 397static const u_int chanflags[IEEE80211_MODE_MAX] = { 398 IEEE80211_CHAN_B, /* IEEE80211_MODE_AUTO */ 399 IEEE80211_CHAN_A, /* IEEE80211_MODE_11A */ 400 IEEE80211_CHAN_B, /* IEEE80211_MODE_11B */ 401 IEEE80211_CHAN_G, /* IEEE80211_MODE_11G */ 402 IEEE80211_CHAN_FHSS, /* IEEE80211_MODE_FH */ 403 IEEE80211_CHAN_A, /* IEEE80211_MODE_TURBO_A (check base channel)*/ 404 IEEE80211_CHAN_G, /* IEEE80211_MODE_TURBO_G */ 405 IEEE80211_CHAN_ST, /* IEEE80211_MODE_STURBO_A */ 406 IEEE80211_CHAN_A, /* IEEE80211_MODE_11NA (check legacy) */ 407 IEEE80211_CHAN_G, /* IEEE80211_MODE_11NG (check legacy) */ 408}; 409 410static void 411add_channels(struct ieee80211vap *vap, 412 struct ieee80211_scan_state *ss, 413 enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) 414{ 415#define N(a) (sizeof(a) / sizeof(a[0])) 416 struct ieee80211com *ic = vap->iv_ic; 417 struct ieee80211_channel *c, *cg; 418 u_int modeflags; 419 int i; 420 421 KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode)); 422 modeflags = chanflags[mode]; 423 for (i = 0; i < nfreq; i++) { 424 if (ss->ss_last >= IEEE80211_SCAN_MAX) 425 break; 426 427 c = ieee80211_find_channel(ic, freq[i], modeflags); 428 if (c == NULL || isexcluded(vap, c)) 429 continue; 430 if (mode == IEEE80211_MODE_AUTO) { 431 /* 432 * XXX special-case 11b/g channels so we select 433 * the g channel if both are present. 434 */ 435 if (IEEE80211_IS_CHAN_B(c) && 436 (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) 437 c = cg; 438 } 439 ss->ss_chans[ss->ss_last++] = c; 440 } 441#undef N 442} 443 444struct scanlist { 445 uint16_t mode; 446 uint16_t count; 447 const uint16_t *list; 448}; 449 450static int 451checktable(const struct scanlist *scan, const struct ieee80211_channel *c) 452{ 453 int i; 454 455 for (; scan->list != NULL; scan++) { 456 for (i = 0; i < scan->count; i++) 457 if (scan->list[i] == c->ic_freq) 458 return 1; 459 } 460 return 0; 461} 462 463static void 464sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 465 const struct scanlist table[]) 466{ 467 struct ieee80211com *ic = vap->iv_ic; 468 struct ieee80211_channel *c; 469 int i; 470 471 for (i = 0; i < ic->ic_nchans; i++) { 472 if (ss->ss_last >= IEEE80211_SCAN_MAX) 473 break; 474 475 c = &ic->ic_channels[i]; 476 /* 477 * Ignore dynamic turbo channels; we scan them 478 * in normal mode (i.e. not boosted). Likewise 479 * for HT channels, they get scanned using 480 * legacy rates. 481 */ 482 if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) 483 continue; 484 485 /* 486 * If a desired mode was specified, scan only 487 * channels that satisfy that constraint. 488 */ 489 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 490 vap->iv_des_mode != ieee80211_chan2mode(c)) 491 continue; 492 493 /* 494 * Skip channels excluded by user request. 495 */ 496 if (isexcluded(vap, c)) 497 continue; 498 499 /* 500 * Add the channel unless it is listed in the 501 * fixed scan order tables. This insures we 502 * don't sweep back in channels we filtered out 503 * above. 504 */ 505 if (checktable(table, c)) 506 continue; 507 508 /* Add channel to scanning list. */ 509 ss->ss_chans[ss->ss_last++] = c; 510 } 511} 512 513static void 514makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, 515 const struct scanlist table[]) 516{ 517 const struct scanlist *scan; 518 enum ieee80211_phymode mode; 519 520 ss->ss_last = 0; 521 /* 522 * Use the table of ordered channels to construct the list 523 * of channels for scanning. Any channels in the ordered 524 * list not in the master list will be discarded. 525 */ 526 for (scan = table; scan->list != NULL; scan++) { 527 mode = scan->mode; 528 if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { 529 /* 530 * If a desired mode was specified, scan only 531 * channels that satisfy that constraint. 532 */ 533 if (vap->iv_des_mode != mode) { 534 /* 535 * The scan table marks 2.4Ghz channels as b 536 * so if the desired mode is 11g, then use 537 * the 11b channel list but upgrade the mode. 538 */ 539 if (vap->iv_des_mode != IEEE80211_MODE_11G || 540 mode != IEEE80211_MODE_11B) 541 continue; 542 mode = IEEE80211_MODE_11G; /* upgrade */ 543 } 544 } else { 545 /* 546 * This lets add_channels upgrade an 11b channel 547 * to 11g if available. 548 */ 549 if (mode == IEEE80211_MODE_11B) 550 mode = IEEE80211_MODE_AUTO; 551 } 552#ifdef IEEE80211_F_XR 553 /* XR does not operate on turbo channels */ 554 if ((vap->iv_flags & IEEE80211_F_XR) && 555 (mode == IEEE80211_MODE_TURBO_A || 556 mode == IEEE80211_MODE_TURBO_G || 557 mode == IEEE80211_MODE_STURBO_A)) 558 continue; 559#endif 560 /* 561 * Add the list of the channels; any that are not 562 * in the master channel list will be discarded. 563 */ 564 add_channels(vap, ss, mode, scan->list, scan->count); 565 } 566 567 /* 568 * Add the channels from the ic that are not present 569 * in the table. 570 */ 571 sweepchannels(ss, vap, table); 572} 573 574static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ 575{ 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; 576static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ 577{ 5170, 5190, 5210, 5230 }; 578static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ 579{ 2412, 2437, 2462, 2442, 2472 }; 580static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ 581{ 5745, 5765, 5785, 5805, 5825 }; 582static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ 583{ 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; 584static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ 585{ 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; 586static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ 587{ 2484 }; 588static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ 589{ 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; 590static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ 591{ 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; 592#ifdef ATH_TURBO_SCAN 593static const uint16_t rcl5[] = /* 3 static turbo channels */ 594{ 5210, 5250, 5290 }; 595static const uint16_t rcl6[] = /* 2 static turbo channels */ 596{ 5760, 5800 }; 597static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ 598{ 5540, 5580, 5620, 5660 }; 599static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ 600{ 2437 }; 601static const uint16_t rcl13[] = /* dynamic Turbo channels */ 602{ 5200, 5240, 5280, 5765, 5805 }; 603#endif /* ATH_TURBO_SCAN */ 604 605#define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a 606 607static const struct scanlist staScanTable[] = { 608 { IEEE80211_MODE_11B, X(rcl3) }, 609 { IEEE80211_MODE_11A, X(rcl1) }, 610 { IEEE80211_MODE_11A, X(rcl2) }, 611 { IEEE80211_MODE_11B, X(rcl8) }, 612 { IEEE80211_MODE_11B, X(rcl9) }, 613 { IEEE80211_MODE_11A, X(rcl4) }, 614#ifdef ATH_TURBO_SCAN 615 { IEEE80211_MODE_STURBO_A, X(rcl5) }, 616 { IEEE80211_MODE_STURBO_A, X(rcl6) }, 617 { IEEE80211_MODE_TURBO_A, X(rcl6x) }, 618 { IEEE80211_MODE_TURBO_A, X(rcl13) }, 619#endif /* ATH_TURBO_SCAN */ 620 { IEEE80211_MODE_11A, X(rcl7) }, 621 { IEEE80211_MODE_11B, X(rcl10) }, 622 { IEEE80211_MODE_11A, X(rcl11) }, 623#ifdef ATH_TURBO_SCAN 624 { IEEE80211_MODE_TURBO_G, X(rcl12) }, 625#endif /* ATH_TURBO_SCAN */ 626 { .list = NULL } 627}; 628 629/* 630 * Start a station-mode scan by populating the channel list. 631 */ 632static int 633sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 634{ 635 struct sta_table *st = ss->ss_priv; 636 637 makescanlist(ss, vap, staScanTable); 638 639 if (ss->ss_mindwell == 0) 640 ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ 641 if (ss->ss_maxdwell == 0) 642 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 643 644 st->st_scangen++; 645 st->st_newscan = 1; 646 647 return 0; 648} 649 650/* 651 * Restart a scan, typically a bg scan but can 652 * also be a fg scan that came up empty. 653 */ 654static int 655sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 656{ 657 struct sta_table *st = ss->ss_priv; 658 659 st->st_newscan = 1; 660 return 0; 661} 662 663/* 664 * Cancel an ongoing scan. 665 */ 666static int 667sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 668{ 669 return 0; 670} 671 672/* unalligned little endian access */ 673#define LE_READ_2(p) \ 674 ((uint16_t) \ 675 ((((const uint8_t *)(p))[0] ) | \ 676 (((const uint8_t *)(p))[1] << 8))) 677 678/* 679 * Demote any supplied 11g channel to 11b. There should 680 * always be an 11b channel but we check anyway... 681 */ 682static struct ieee80211_channel * 683demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) 684{ 685 struct ieee80211_channel *c; 686 687 if (IEEE80211_IS_CHAN_ANYG(chan) && 688 vap->iv_des_mode == IEEE80211_MODE_AUTO) { 689 c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, 690 (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | 691 IEEE80211_CHAN_B); 692 if (c != NULL) 693 chan = c; 694 } 695 return chan; 696} 697 698static int 699maxrate(const struct ieee80211_scan_entry *se) 700{ 701 const struct ieee80211_ie_htcap *htcap = 702 (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; 703 int rmax, r, i; 704 uint16_t caps; 705 706 rmax = 0; 707 if (htcap != NULL) { 708 /* 709 * HT station; inspect supported MCS and then adjust 710 * rate by channel width. Could also include short GI 711 * in this if we want to be extra accurate. 712 */ 713 /* XXX assumes MCS15 is max */ 714 for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--) 715 ; 716 if (i >= 0) { 717 caps = LE_READ_2(&htcap->hc_cap); 718 /* XXX short/long GI */ 719 if (caps & IEEE80211_HTCAP_CHWIDTH40) 720 rmax = ieee80211_htrates[i].ht40_rate_400ns; 721 else 722 rmax = ieee80211_htrates[i].ht40_rate_800ns; 723 } 724 } 725 for (i = 0; i < se->se_rates[1]; i++) { 726 r = se->se_rates[2+i] & IEEE80211_RATE_VAL; 727 if (r > rmax) 728 rmax = r; 729 } 730 for (i = 0; i < se->se_xrates[1]; i++) { 731 r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; 732 if (r > rmax) 733 rmax = r; 734 } 735 return rmax; 736} 737 738/* 739 * Compare the capabilities of two entries and decide which is 740 * more desirable (return >0 if a is considered better). Note 741 * that we assume compatibility/usability has already been checked 742 * so we don't need to (e.g. validate whether privacy is supported). 743 * Used to select the best scan candidate for association in a BSS. 744 */ 745static int 746sta_compare(const struct sta_entry *a, const struct sta_entry *b) 747{ 748#define PREFER(_a,_b,_what) do { \ 749 if (((_a) ^ (_b)) & (_what)) \ 750 return ((_a) & (_what)) ? 1 : -1; \ 751} while (0) 752 int maxa, maxb; 753 int8_t rssia, rssib; 754 int weight; 755 756 /* privacy support */ 757 PREFER(a->base.se_capinfo, b->base.se_capinfo, 758 IEEE80211_CAPINFO_PRIVACY); 759 760 /* compare count of previous failures */ 761 weight = b->se_fails - a->se_fails; 762 if (abs(weight) > 1) 763 return weight; 764 765 /* 766 * Compare rssi. If the two are considered equivalent 767 * then fallback to other criteria. We threshold the 768 * comparisons to avoid selecting an ap purely by rssi 769 * when both values may be good but one ap is otherwise 770 * more desirable (e.g. an 11b-only ap with stronger 771 * signal than an 11g ap). 772 */ 773 rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); 774 rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); 775 if (abs(rssib - rssia) < 5) { 776 /* best/max rate preferred if signal level close enough XXX */ 777 maxa = maxrate(&a->base); 778 maxb = maxrate(&b->base); 779 if (maxa != maxb) 780 return maxa - maxb; 781 /* XXX use freq for channel preference */ 782 /* for now just prefer 5Ghz band to all other bands */ 783 PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), 784 IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); 785 } 786 /* all things being equal, use signal level */ 787 return a->base.se_rssi - b->base.se_rssi; 788#undef PREFER 789} 790 791/* 792 * Check rate set suitability and return the best supported rate. 793 * XXX inspect MCS for HT 794 */ 795static int 796check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, 797 const struct ieee80211_scan_entry *se) 798{ 799#define RV(v) ((v) & IEEE80211_RATE_VAL) 800 const struct ieee80211_rateset *srs; 801 int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; 802 const uint8_t *rs; 803 804 okrate = badrate = 0; 805 806 srs = ieee80211_get_suprates(vap->iv_ic, chan); 807 nrs = se->se_rates[1]; 808 rs = se->se_rates+2; 809 /* XXX MCS */ 810 ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; 811 fixedrate = IEEE80211_FIXED_RATE_NONE; 812again: 813 for (i = 0; i < nrs; i++) { 814 r = RV(rs[i]); 815 badrate = r; 816 /* 817 * Check any fixed rate is included. 818 */ 819 if (r == ucastrate) 820 fixedrate = r; 821 /* 822 * Check against our supported rates. 823 */ 824 for (j = 0; j < srs->rs_nrates; j++) 825 if (r == RV(srs->rs_rates[j])) { 826 if (r > okrate) /* NB: track max */ 827 okrate = r; 828 break; 829 } 830 831 if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { 832 /* 833 * Don't try joining a BSS, if we don't support 834 * one of its basic rates. 835 */ 836 okrate = 0; 837 goto back; 838 } 839 } 840 if (rs == se->se_rates+2) { 841 /* scan xrates too; sort of an algol68-style for loop */ 842 nrs = se->se_xrates[1]; 843 rs = se->se_xrates+2; 844 goto again; 845 } 846 847back: 848 if (okrate == 0 || ucastrate != fixedrate) 849 return badrate | IEEE80211_RATE_BASIC; 850 else 851 return RV(okrate); 852#undef RV 853} 854 855static int 856match_ssid(const uint8_t *ie, 857 int nssid, const struct ieee80211_scan_ssid ssids[]) 858{ 859 int i; 860 861 for (i = 0; i < nssid; i++) { 862 if (ie[1] == ssids[i].len && 863 memcmp(ie+2, ssids[i].ssid, ie[1]) == 0) 864 return 1; 865 } 866 return 0; 867} 868 869/* 870 * Test a scan candidate for suitability/compatibility. 871 */ 872static int 873match_bss(struct ieee80211vap *vap, 874 const struct ieee80211_scan_state *ss, struct sta_entry *se0, 875 int debug) 876{ 877 struct ieee80211com *ic = vap->iv_ic; 878 struct ieee80211_scan_entry *se = &se0->base; 879 uint8_t rate; 880 int fail; 881 882 fail = 0; 883 if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) 884 fail |= MATCH_CHANNEL; 885 /* 886 * NB: normally the desired mode is used to construct 887 * the channel list, but it's possible for the scan 888 * cache to include entries for stations outside this 889 * list so we check the desired mode here to weed them 890 * out. 891 */ 892 if (vap->iv_des_mode != IEEE80211_MODE_AUTO && 893 (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != 894 chanflags[vap->iv_des_mode]) 895 fail |= MATCH_CHANNEL; 896 if (vap->iv_opmode == IEEE80211_M_IBSS) { 897 if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) 898 fail |= MATCH_CAPINFO; 899 } else { 900 if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) 901 fail |= MATCH_CAPINFO; 902 /* 903 * If 11d is enabled and we're attempting to join a bss 904 * that advertises it's country code then compare our 905 * current settings to what we fetched from the country ie. 906 * If our country code is unspecified or different then do 907 * not attempt to join the bss. We should have already 908 * dispatched an event to user space that identifies the 909 * new country code so our regdomain config should match. 910 */ 911 if ((IEEE80211_IS_CHAN_11D(se->se_chan) || 912 (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && 913 se->se_cc[0] != 0 && 914 (ic->ic_regdomain.country == CTRY_DEFAULT || 915 !isocmp(se->se_cc, ic->ic_regdomain.isocc))) 916 fail |= MATCH_CC; 917 } 918 if (vap->iv_flags & IEEE80211_F_PRIVACY) { 919 if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) 920 fail |= MATCH_PRIVACY; 921 } else { 922 /* XXX does this mean privacy is supported or required? */ 923 if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) 924 fail |= MATCH_PRIVACY; 925 } 926 se0->se_flags &= ~STA_DEMOTE11B; 927 rate = check_rate(vap, se->se_chan, se); 928 if (rate & IEEE80211_RATE_BASIC) { 929 fail |= MATCH_RATE; 930 /* 931 * An 11b-only ap will give a rate mismatch if there is an 932 * OFDM fixed tx rate for 11g. Try downgrading the channel 933 * in the scan list to 11b and retry the rate check. 934 */ 935 if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { 936 rate = check_rate(vap, demote11b(vap, se->se_chan), se); 937 if ((rate & IEEE80211_RATE_BASIC) == 0) { 938 fail &= ~MATCH_RATE; 939 se0->se_flags |= STA_DEMOTE11B; 940 } 941 } 942 } else if (rate < 2*24) { 943 /* 944 * This is an 11b-only ap. Check the desired mode in 945 * case that needs to be honored (mode 11g filters out 946 * 11b-only ap's). Otherwise force any 11g channel used 947 * in scanning to be demoted. 948 * 949 * NB: we cheat a bit here by looking at the max rate; 950 * we could/should check the rates. 951 */ 952 if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || 953 vap->iv_des_mode == IEEE80211_MODE_11B)) 954 fail |= MATCH_RATE; 955 else 956 se0->se_flags |= STA_DEMOTE11B; 957 } 958 if (ss->ss_nssid != 0 && 959 !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) 960 fail |= MATCH_SSID; 961 if ((vap->iv_flags & IEEE80211_F_DESBSSID) && 962 !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) 963 fail |= MATCH_BSSID; 964 if (se0->se_fails >= STA_FAILS_MAX) 965 fail |= MATCH_FAILS; 966 if (se0->se_notseen >= STA_PURGE_SCANS) 967 fail |= MATCH_NOTSEEN; 968 if (se->se_rssi < STA_RSSI_MIN) 969 fail |= MATCH_RSSI; 970#ifdef IEEE80211_DEBUG 971 if (ieee80211_msg(vap, debug)) { 972 printf(" %c %s", 973 fail & MATCH_FAILS ? '=' : 974 fail & MATCH_NOTSEEN ? '^' : 975 fail & MATCH_CC ? '$' : 976 fail ? '-' : '+', ether_sprintf(se->se_macaddr)); 977 printf(" %s%c", ether_sprintf(se->se_bssid), 978 fail & MATCH_BSSID ? '!' : ' '); 979 printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), 980 fail & MATCH_CHANNEL ? '!' : ' '); 981 printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); 982 printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, 983 fail & MATCH_RATE ? '!' : ' '); 984 printf(" %4s%c", 985 (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : 986 (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : 987 "????", 988 fail & MATCH_CAPINFO ? '!' : ' '); 989 printf(" %3s%c ", 990 (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? 991 "wep" : "no", 992 fail & MATCH_PRIVACY ? '!' : ' '); 993 ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); 994 printf("%s\n", fail & MATCH_SSID ? "!" : ""); 995 } 996#endif 997 return fail; 998} 999 1000static void 1001sta_update_notseen(struct sta_table *st) 1002{ 1003 struct sta_entry *se; 1004 1005 mtx_lock(&st->st_lock); 1006 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1007 /* 1008 * If seen the reset and don't bump the count; 1009 * otherwise bump the ``not seen'' count. Note 1010 * that this insures that stations for which we 1011 * see frames while not scanning but not during 1012 * this scan will not be penalized. 1013 */ 1014 if (se->se_seen) 1015 se->se_seen = 0; 1016 else 1017 se->se_notseen++; 1018 } 1019 mtx_unlock(&st->st_lock); 1020} 1021 1022static void 1023sta_dec_fails(struct sta_table *st) 1024{ 1025 struct sta_entry *se; 1026 1027 mtx_lock(&st->st_lock); 1028 TAILQ_FOREACH(se, &st->st_entry, se_list) 1029 if (se->se_fails) 1030 se->se_fails--; 1031 mtx_unlock(&st->st_lock); 1032} 1033 1034static struct sta_entry * 1035select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) 1036{ 1037 struct sta_table *st = ss->ss_priv; 1038 struct sta_entry *se, *selbs = NULL; 1039 1040 IEEE80211_DPRINTF(vap, debug, " %s\n", 1041 "macaddr bssid chan rssi rate flag wep essid"); 1042 mtx_lock(&st->st_lock); 1043 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1044 ieee80211_ies_expand(&se->base.se_ies); 1045 if (match_bss(vap, ss, se, debug) == 0) { 1046 if (selbs == NULL) 1047 selbs = se; 1048 else if (sta_compare(se, selbs) > 0) 1049 selbs = se; 1050 } 1051 } 1052 mtx_unlock(&st->st_lock); 1053 1054 return selbs; 1055} 1056 1057/* 1058 * Pick an ap or ibss network to join or find a channel 1059 * to use to start an ibss network. 1060 */ 1061static int 1062sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1063{ 1064 struct sta_table *st = ss->ss_priv; 1065 struct sta_entry *selbs; 1066 struct ieee80211_channel *chan; 1067 1068 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1069 ("wrong mode %u", vap->iv_opmode)); 1070 1071 if (st->st_newscan) { 1072 sta_update_notseen(st); 1073 st->st_newscan = 0; 1074 } 1075 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1076 /* 1077 * Manual/background scan, don't select+join the 1078 * bss, just return. The scanning framework will 1079 * handle notification that this has completed. 1080 */ 1081 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1082 return 1; 1083 } 1084 /* 1085 * Automatic sequencing; look for a candidate and 1086 * if found join the network. 1087 */ 1088 /* NB: unlocked read should be ok */ 1089 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1090 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1091 "%s: no scan candidate\n", __func__); 1092 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1093 return 0; 1094notfound: 1095 /* 1096 * If nothing suitable was found decrement 1097 * the failure counts so entries will be 1098 * reconsidered the next time around. We 1099 * really want to do this only for sta's 1100 * where we've previously had some success. 1101 */ 1102 sta_dec_fails(st); 1103 st->st_newscan = 1; 1104 return 0; /* restart scan */ 1105 } 1106 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1107 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1108 return (selbs != NULL); 1109 if (selbs == NULL) 1110 goto notfound; 1111 chan = selbs->base.se_chan; 1112 if (selbs->se_flags & STA_DEMOTE11B) 1113 chan = demote11b(vap, chan); 1114 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1115 goto notfound; 1116 return 1; /* terminate scan */ 1117} 1118 1119/* 1120 * Lookup an entry in the scan cache. We assume we're 1121 * called from the bottom half or such that we don't need 1122 * to block the bottom half so that it's safe to return 1123 * a reference to an entry w/o holding the lock on the table. 1124 */ 1125static struct sta_entry * 1126sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1127{ 1128 struct sta_entry *se; 1129 int hash = STA_HASH(macaddr); 1130 1131 mtx_lock(&st->st_lock); 1132 LIST_FOREACH(se, &st->st_hash[hash], se_hash) 1133 if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) 1134 break; 1135 mtx_unlock(&st->st_lock); 1136 1137 return se; /* NB: unlocked */ 1138} 1139 1140static void 1141sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1142{ 1143 struct ieee80211com *ic = vap->iv_ic; 1144 struct ieee80211_node *ni = vap->iv_bss; 1145 struct sta_table *st = ss->ss_priv; 1146 enum ieee80211_phymode mode; 1147 struct sta_entry *se, *selbs; 1148 uint8_t roamRate, curRate, ucastRate; 1149 int8_t roamRssi, curRssi; 1150 1151 se = sta_lookup(st, ni->ni_macaddr); 1152 if (se == NULL) { 1153 /* XXX something is wrong */ 1154 return; 1155 } 1156 1157 mode = ieee80211_chan2mode(ic->ic_bsschan); 1158 roamRate = vap->iv_roamparms[mode].rate; 1159 roamRssi = vap->iv_roamparms[mode].rssi; 1160 ucastRate = vap->iv_txparms[mode].ucastrate; 1161 /* NB: the most up to date rssi is in the node, not the scan cache */ 1162 curRssi = ic->ic_node_getrssi(ni); 1163 if (ucastRate == IEEE80211_FIXED_RATE_NONE) { 1164 curRate = ni->ni_txrate; 1165 roamRate &= IEEE80211_RATE_VAL; 1166 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1167 "%s: currssi %d currate %u roamrssi %d roamrate %u\n", 1168 __func__, curRssi, curRate, roamRssi, roamRate); 1169 } else { 1170 curRate = roamRate; /* NB: insure compare below fails */ 1171 IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, 1172 "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); 1173 } 1174 /* 1175 * Check if a new ap should be used and switch. 1176 * XXX deauth current ap 1177 */ 1178 if (curRate < roamRate || curRssi < roamRssi) { 1179 if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 1180 /* 1181 * Scan cache contents are too old; force a scan now 1182 * if possible so we have current state to make a 1183 * decision with. We don't kick off a bg scan if 1184 * we're using dynamic turbo and boosted or if the 1185 * channel is busy. 1186 * XXX force immediate switch on scan complete 1187 */ 1188 if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && 1189 time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) 1190 ieee80211_bg_scan(vap, 0); 1191 return; 1192 } 1193 se->base.se_rssi = curRssi; 1194 selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); 1195 if (selbs != NULL && selbs != se) { 1196 struct ieee80211_channel *chan; 1197 1198 IEEE80211_DPRINTF(vap, 1199 IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, 1200 "%s: ROAM: curRate %u, roamRate %u, " 1201 "curRssi %d, roamRssi %d\n", __func__, 1202 curRate, roamRate, curRssi, roamRssi); 1203 1204 chan = selbs->base.se_chan; 1205 if (selbs->se_flags & STA_DEMOTE11B) 1206 chan = demote11b(vap, chan); 1207 (void) ieee80211_sta_join(vap, chan, &selbs->base); 1208 } 1209 } 1210} 1211 1212/* 1213 * Age entries in the scan cache. 1214 * XXX also do roaming since it's convenient 1215 */ 1216static void 1217sta_age(struct ieee80211_scan_state *ss) 1218{ 1219 struct ieee80211vap *vap = ss->ss_vap; 1220 1221 adhoc_age(ss); 1222 /* 1223 * If rate control is enabled check periodically to see if 1224 * we should roam from our current connection to one that 1225 * might be better. This only applies when we're operating 1226 * in sta mode and automatic roaming is set. 1227 * XXX defer if busy 1228 * XXX repeater station 1229 * XXX do when !bgscan? 1230 */ 1231 KASSERT(vap->iv_opmode == IEEE80211_M_STA, 1232 ("wrong mode %u", vap->iv_opmode)); 1233 if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && 1234 (vap->iv_ic->ic_flags & IEEE80211_F_BGSCAN) && 1235 vap->iv_state >= IEEE80211_S_RUN) 1236 /* XXX vap is implicit */ 1237 sta_roam_check(ss, vap); 1238} 1239 1240/* 1241 * Iterate over the entries in the scan cache, invoking 1242 * the callback function on each one. 1243 */ 1244static void 1245sta_iterate(struct ieee80211_scan_state *ss, 1246 ieee80211_scan_iter_func *f, void *arg) 1247{ 1248 struct sta_table *st = ss->ss_priv; 1249 struct sta_entry *se; 1250 u_int gen; 1251 1252 mtx_lock(&st->st_scanlock); 1253 gen = st->st_scaniter++; 1254restart: 1255 mtx_lock(&st->st_lock); 1256 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1257 if (se->se_scangen != gen) { 1258 se->se_scangen = gen; 1259 /* update public state */ 1260 se->base.se_age = ticks - se->se_lastupdate; 1261 mtx_unlock(&st->st_lock); 1262 (*f)(arg, &se->base); 1263 goto restart; 1264 } 1265 } 1266 mtx_unlock(&st->st_lock); 1267 1268 mtx_unlock(&st->st_scanlock); 1269} 1270 1271static void 1272sta_assoc_fail(struct ieee80211_scan_state *ss, 1273 const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) 1274{ 1275 struct sta_table *st = ss->ss_priv; 1276 struct sta_entry *se; 1277 1278 se = sta_lookup(st, macaddr); 1279 if (se != NULL) { 1280 se->se_fails++; 1281 se->se_lastfail = ticks; 1282 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1283 macaddr, "%s: reason %u fails %u", 1284 __func__, reason, se->se_fails); 1285 } 1286} 1287 1288static void 1289sta_assoc_success(struct ieee80211_scan_state *ss, 1290 const uint8_t macaddr[IEEE80211_ADDR_LEN]) 1291{ 1292 struct sta_table *st = ss->ss_priv; 1293 struct sta_entry *se; 1294 1295 se = sta_lookup(st, macaddr); 1296 if (se != NULL) { 1297#if 0 1298 se->se_fails = 0; 1299 IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, 1300 macaddr, "%s: fails %u", 1301 __func__, se->se_fails); 1302#endif 1303 se->se_lastassoc = ticks; 1304 } 1305} 1306 1307static const struct ieee80211_scanner sta_default = { 1308 .scan_name = "default", 1309 .scan_attach = sta_attach, 1310 .scan_detach = sta_detach, 1311 .scan_start = sta_start, 1312 .scan_restart = sta_restart, 1313 .scan_cancel = sta_cancel, 1314 .scan_end = sta_pick_bss, 1315 .scan_flush = sta_flush, 1316 .scan_add = sta_add, 1317 .scan_age = sta_age, 1318 .scan_iterate = sta_iterate, 1319 .scan_assoc_fail = sta_assoc_fail, 1320 .scan_assoc_success = sta_assoc_success, 1321}; 1322 1323/* 1324 * Adhoc mode-specific support. 1325 */ 1326 1327static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ 1328{ 5180, 5200, 5220, 5240 }; 1329static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ 1330{ 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; 1331static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ 1332{ 5170, 5190, 5210, 5230 }; 1333static const uint16_t adhoc11b[] = /* 10, 11 */ 1334{ 2457, 2462 }; 1335 1336static const struct scanlist adhocScanTable[] = { 1337 { IEEE80211_MODE_11B, X(adhoc11b) }, 1338 { IEEE80211_MODE_11A, X(adhocWorld) }, 1339 { IEEE80211_MODE_11A, X(adhocFcc3) }, 1340 { IEEE80211_MODE_11B, X(adhocMkk) }, 1341 { .list = NULL } 1342}; 1343#undef X 1344 1345/* 1346 * Start an adhoc-mode scan by populating the channel list. 1347 */ 1348static int 1349adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1350{ 1351 struct sta_table *st = ss->ss_priv; 1352 1353 makescanlist(ss, vap, adhocScanTable); 1354 1355 if (ss->ss_mindwell == 0) 1356 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1357 if (ss->ss_maxdwell == 0) 1358 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1359 1360 st->st_scangen++; 1361 st->st_newscan = 1; 1362 1363 return 0; 1364} 1365 1366/* 1367 * Select a channel to start an adhoc network on. 1368 * The channel list was populated with appropriate 1369 * channels so select one that looks least occupied. 1370 */ 1371static struct ieee80211_channel * 1372adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) 1373{ 1374 struct sta_table *st = ss->ss_priv; 1375 struct sta_entry *se; 1376 struct ieee80211_channel *c, *bestchan; 1377 int i, bestrssi, maxrssi; 1378 1379 bestchan = NULL; 1380 bestrssi = -1; 1381 1382 mtx_lock(&st->st_lock); 1383 for (i = 0; i < ss->ss_last; i++) { 1384 c = ss->ss_chans[i]; 1385 /* never consider a channel with radar */ 1386 if (IEEE80211_IS_CHAN_RADAR(c)) 1387 continue; 1388 /* skip channels disallowed by regulatory settings */ 1389 if (IEEE80211_IS_CHAN_NOADHOC(c)) 1390 continue; 1391 /* check channel attributes for band compatibility */ 1392 if (flags != 0 && (c->ic_flags & flags) != flags) 1393 continue; 1394 maxrssi = 0; 1395 TAILQ_FOREACH(se, &st->st_entry, se_list) { 1396 if (se->base.se_chan != c) 1397 continue; 1398 if (se->base.se_rssi > maxrssi) 1399 maxrssi = se->base.se_rssi; 1400 } 1401 if (bestchan == NULL || maxrssi < bestrssi) 1402 bestchan = c; 1403 } 1404 mtx_unlock(&st->st_lock); 1405 1406 return bestchan; 1407} 1408 1409/* 1410 * Pick an ibss network to join or find a channel 1411 * to use to start an ibss network. 1412 */ 1413static int 1414adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1415{ 1416 struct sta_table *st = ss->ss_priv; 1417 struct sta_entry *selbs; 1418 struct ieee80211_channel *chan; 1419 1420 KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || 1421 vap->iv_opmode == IEEE80211_M_AHDEMO, 1422 ("wrong opmode %u", vap->iv_opmode)); 1423 1424 if (st->st_newscan) { 1425 sta_update_notseen(st); 1426 st->st_newscan = 0; 1427 } 1428 if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { 1429 /* 1430 * Manual/background scan, don't select+join the 1431 * bss, just return. The scanning framework will 1432 * handle notification that this has completed. 1433 */ 1434 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1435 return 1; 1436 } 1437 /* 1438 * Automatic sequencing; look for a candidate and 1439 * if found join the network. 1440 */ 1441 /* NB: unlocked read should be ok */ 1442 if (TAILQ_FIRST(&st->st_entry) == NULL) { 1443 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1444 "%s: no scan candidate\n", __func__); 1445 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1446 return 0; 1447notfound: 1448 if (vap->iv_des_nssid) { 1449 /* 1450 * No existing adhoc network to join and we have 1451 * an ssid; start one up. If no channel was 1452 * specified, try to select a channel. 1453 */ 1454 if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || 1455 IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { 1456 struct ieee80211com *ic = vap->iv_ic; 1457 1458 chan = adhoc_pick_channel(ss, 0); 1459 if (chan != NULL) 1460 chan = ieee80211_ht_adjust_channel(ic, 1461 chan, vap->iv_flags_ext); 1462 } else 1463 chan = vap->iv_des_chan; 1464 if (chan != NULL) { 1465 ieee80211_create_ibss(vap, chan); 1466 return 1; 1467 } 1468 } 1469 /* 1470 * If nothing suitable was found decrement 1471 * the failure counts so entries will be 1472 * reconsidered the next time around. We 1473 * really want to do this only for sta's 1474 * where we've previously had some success. 1475 */ 1476 sta_dec_fails(st); 1477 st->st_newscan = 1; 1478 return 0; /* restart scan */ 1479 } 1480 selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); 1481 if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) 1482 return (selbs != NULL); 1483 if (selbs == NULL) 1484 goto notfound; 1485 chan = selbs->base.se_chan; 1486 if (selbs->se_flags & STA_DEMOTE11B) 1487 chan = demote11b(vap, chan); 1488 if (!ieee80211_sta_join(vap, chan, &selbs->base)) 1489 goto notfound; 1490 return 1; /* terminate scan */ 1491} 1492 1493/* 1494 * Age entries in the scan cache. 1495 */ 1496static void 1497adhoc_age(struct ieee80211_scan_state *ss) 1498{ 1499 struct sta_table *st = ss->ss_priv; 1500 struct sta_entry *se, *next; 1501 1502 mtx_lock(&st->st_lock); 1503 TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { 1504 if (se->se_notseen > STA_PURGE_SCANS) { 1505 TAILQ_REMOVE(&st->st_entry, se, se_list); 1506 LIST_REMOVE(se, se_hash); 1507 ieee80211_ies_cleanup(&se->base.se_ies); 1508 FREE(se, M_80211_SCAN); 1509 } 1510 } 1511 mtx_unlock(&st->st_lock); 1512} 1513 1514static const struct ieee80211_scanner adhoc_default = { 1515 .scan_name = "default", 1516 .scan_attach = sta_attach, 1517 .scan_detach = sta_detach, 1518 .scan_start = adhoc_start, 1519 .scan_restart = sta_restart, 1520 .scan_cancel = sta_cancel, 1521 .scan_end = adhoc_pick_bss, 1522 .scan_flush = sta_flush, 1523 .scan_pickchan = adhoc_pick_channel, 1524 .scan_add = sta_add, 1525 .scan_age = adhoc_age, 1526 .scan_iterate = sta_iterate, 1527 .scan_assoc_fail = sta_assoc_fail, 1528 .scan_assoc_success = sta_assoc_success, 1529}; 1530 1531static void 1532ap_force_promisc(struct ieee80211com *ic) 1533{ 1534 struct ifnet *ifp = ic->ic_ifp; 1535 1536 IEEE80211_LOCK(ic); 1537 /* set interface into promiscuous mode */ 1538 ifp->if_flags |= IFF_PROMISC; 1539 ic->ic_update_promisc(ifp); 1540 IEEE80211_UNLOCK(ic); 1541} 1542 1543static void 1544ap_reset_promisc(struct ieee80211com *ic) 1545{ 1546 IEEE80211_LOCK(ic); 1547 ieee80211_syncifflag_locked(ic, IFF_PROMISC); 1548 IEEE80211_UNLOCK(ic); 1549} 1550 1551static int 1552ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1553{ 1554 struct sta_table *st = ss->ss_priv; 1555 1556 makescanlist(ss, vap, staScanTable); 1557 1558 if (ss->ss_mindwell == 0) 1559 ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ 1560 if (ss->ss_maxdwell == 0) 1561 ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ 1562 1563 st->st_scangen++; 1564 st->st_newscan = 1; 1565 1566 ap_force_promisc(vap->iv_ic); 1567 return 0; 1568} 1569 1570/* 1571 * Cancel an ongoing scan. 1572 */ 1573static int 1574ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1575{ 1576 ap_reset_promisc(vap->iv_ic); 1577 return 0; 1578} 1579 1580/* 1581 * Pick a quiet channel to use for ap operation. 1582 */ 1583static struct ieee80211_channel * 1584ap_pick_channel(struct ieee80211_scan_state *ss, int flags) 1585{ 1586 struct sta_table *st = ss->ss_priv; 1587 struct ieee80211_channel *bestchan = NULL; 1588 int i; 1589 1590 /* XXX select channel more intelligently, e.g. channel spread, power */ 1591 /* NB: use scan list order to preserve channel preference */ 1592 for (i = 0; i < ss->ss_last; i++) { 1593 struct ieee80211_channel *chan = ss->ss_chans[i]; 1594 /* 1595 * If the channel is unoccupied the max rssi 1596 * should be zero; just take it. Otherwise 1597 * track the channel with the lowest rssi and 1598 * use that when all channels appear occupied. 1599 */ 1600 if (IEEE80211_IS_CHAN_RADAR(chan)) 1601 continue; 1602 if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) 1603 continue; 1604 /* check channel attributes for band compatibility */ 1605 if (flags != 0 && (chan->ic_flags & flags) != flags) 1606 continue; 1607 /* XXX channel have interference */ 1608 if (st->st_maxrssi[chan->ic_ieee] == 0) { 1609 /* XXX use other considerations */ 1610 return chan; 1611 } 1612 if (bestchan == NULL || 1613 st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) 1614 bestchan = chan; 1615 } 1616 return bestchan; 1617} 1618 1619/* 1620 * Pick a quiet channel to use for ap operation. 1621 */ 1622static int 1623ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) 1624{ 1625 struct ieee80211com *ic = vap->iv_ic; 1626 struct ieee80211_channel *bestchan; 1627 1628 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, 1629 ("wrong opmode %u", vap->iv_opmode)); 1630 bestchan = ap_pick_channel(ss, 0); 1631 if (bestchan == NULL) { 1632 /* no suitable channel, should not happen */ 1633 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1634 "%s: no suitable channel! (should not happen)\n", __func__); 1635 /* XXX print something? */ 1636 return 0; /* restart scan */ 1637 } 1638 /* 1639 * If this is a dynamic turbo channel, start with the unboosted one. 1640 */ 1641 if (IEEE80211_IS_CHAN_TURBO(bestchan)) { 1642 bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, 1643 bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); 1644 if (bestchan == NULL) { 1645 /* should never happen ?? */ 1646 return 0; 1647 } 1648 } 1649 ap_reset_promisc(ic); 1650 if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { 1651 /* 1652 * Manual/background scan, don't select+join the 1653 * bss, just return. The scanning framework will 1654 * handle notification that this has completed. 1655 */ 1656 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 1657 return 1; 1658 } 1659 ieee80211_create_ibss(vap, 1660 ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ext)); 1661 return 1; 1662} 1663 1664static const struct ieee80211_scanner ap_default = { 1665 .scan_name = "default", 1666 .scan_attach = sta_attach, 1667 .scan_detach = sta_detach, 1668 .scan_start = ap_start, 1669 .scan_restart = sta_restart, 1670 .scan_cancel = ap_cancel, 1671 .scan_end = ap_end, 1672 .scan_flush = sta_flush, 1673 .scan_pickchan = ap_pick_channel, 1674 .scan_add = sta_add, 1675 .scan_age = adhoc_age, 1676 .scan_iterate = sta_iterate, 1677 .scan_assoc_success = sta_assoc_success, 1678 .scan_assoc_fail = sta_assoc_fail, 1679}; 1680 1681/* 1682 * Module glue. 1683 */ 1684IEEE80211_SCANNER_MODULE(sta, 1); 1685IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); 1686IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); 1687IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); 1688IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); 1689