ieee80211_scan.c revision 188782
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.c 188782 2009-02-19 05:21:54Z sam $"); 28 29/* 30 * IEEE 802.11 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 38#include <sys/socket.h> 39 40#include <net/if.h> 41#include <net/if_media.h> 42#include <net/ethernet.h> 43 44#include <net80211/ieee80211_var.h> 45 46#include <net/bpf.h> 47 48struct scan_state { 49 struct ieee80211_scan_state base; /* public state */ 50 51 u_int ss_iflags; /* flags used internally */ 52#define ISCAN_MINDWELL 0x0001 /* min dwell time reached */ 53#define ISCAN_DISCARD 0x0002 /* discard rx'd frames */ 54#define ISCAN_CANCEL 0x0004 /* cancel current scan */ 55#define ISCAN_START 0x0008 /* 1st time through next_scan */ 56 unsigned long ss_chanmindwell; /* min dwell on curchan */ 57 unsigned long ss_scanend; /* time scan must stop */ 58 u_int ss_duration; /* duration for next scan */ 59 struct callout ss_scan_timer; /* scan timer */ 60}; 61#define SCAN_PRIVATE(ss) ((struct scan_state *) ss) 62 63/* 64 * Amount of time to go off-channel during a background 65 * scan. This value should be large enough to catch most 66 * ap's but short enough that we can return on-channel 67 * before our listen interval expires. 68 * 69 * XXX tunable 70 * XXX check against configured listen interval 71 */ 72#define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150) 73 74/* 75 * Roaming-related defaults. RSSI thresholds are as returned by the 76 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e 77 * .5M units) or MCS. 78 */ 79/* rssi thresholds */ 80#define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */ 81#define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */ 82#define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */ 83/* transmit rate thresholds */ 84#define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */ 85#define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */ 86#define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */ 87#define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */ 88#define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */ 89#define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */ 90 91static void scan_restart_pwrsav(void *); 92static void scan_curchan(struct ieee80211_scan_state *, unsigned long); 93static void scan_mindwell(struct ieee80211_scan_state *); 94static void scan_next(void *); 95 96MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state"); 97 98void 99ieee80211_scan_attach(struct ieee80211com *ic) 100{ 101 struct scan_state *ss; 102 103 ss = (struct scan_state *) malloc(sizeof(struct scan_state), 104 M_80211_SCAN, M_NOWAIT | M_ZERO); 105 if (ss == NULL) { 106 ic->ic_scan = NULL; 107 return; 108 } 109 callout_init_mtx(&ss->ss_scan_timer, IEEE80211_LOCK_OBJ(ic), 0); 110 ic->ic_scan = &ss->base; 111 112 ic->ic_scan_curchan = scan_curchan; 113 ic->ic_scan_mindwell = scan_mindwell; 114} 115 116void 117ieee80211_scan_detach(struct ieee80211com *ic) 118{ 119 struct ieee80211_scan_state *ss = ic->ic_scan; 120 121 if (ss != NULL) { 122 callout_drain(&SCAN_PRIVATE(ss)->ss_scan_timer); 123 if (ss->ss_ops != NULL) { 124 ss->ss_ops->scan_detach(ss); 125 ss->ss_ops = NULL; 126 } 127 ic->ic_flags &= ~IEEE80211_F_SCAN; 128 ic->ic_scan = NULL; 129 free(SCAN_PRIVATE(ss), M_80211_SCAN); 130 } 131} 132 133static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = { 134 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT, 135 .rate = ROAM_RATE_11A_DEFAULT }, 136 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT, 137 .rate = ROAM_RATE_11B_DEFAULT }, 138 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT, 139 .rate = ROAM_RATE_11BONLY_DEFAULT }, 140 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT, 141 .rate = ROAM_RATE_11A_DEFAULT }, 142 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT, 143 .rate = ROAM_RATE_11A_DEFAULT }, 144 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT, 145 .rate = ROAM_RATE_11A_DEFAULT }, 146 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT, 147 .rate = ROAM_RATE_HALF_DEFAULT }, 148 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT, 149 .rate = ROAM_RATE_QUARTER_DEFAULT }, 150 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT, 151 .rate = ROAM_MCS_11N_DEFAULT }, 152 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT, 153 .rate = ROAM_MCS_11N_DEFAULT }, 154}; 155 156void 157ieee80211_scan_vattach(struct ieee80211vap *vap) 158{ 159 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz; 160 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz; 161 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz; 162 163 vap->iv_roaming = IEEE80211_ROAMING_AUTO; 164 memcpy(vap->iv_roamparms, defroam, sizeof(defroam)); 165} 166 167void 168ieee80211_scan_vdetach(struct ieee80211vap *vap) 169{ 170 struct ieee80211com *ic = vap->iv_ic; 171 struct ieee80211_scan_state *ss; 172 173 IEEE80211_LOCK(ic); 174 ss = ic->ic_scan; 175 if (ss != NULL && ss->ss_vap == vap) { 176 if (ic->ic_flags & IEEE80211_F_SCAN) { 177 /* XXX callout_drain */ 178 callout_stop(&SCAN_PRIVATE(ss)->ss_scan_timer); 179 ic->ic_flags &= ~IEEE80211_F_SCAN; 180 } 181 if (ss->ss_ops != NULL) { 182 ss->ss_ops->scan_detach(ss); 183 ss->ss_ops = NULL; 184 } 185 ss->ss_vap = NULL; 186 } 187 IEEE80211_UNLOCK(ic); 188} 189 190/* 191 * Simple-minded scanner module support. 192 */ 193static const char *scan_modnames[IEEE80211_OPMODE_MAX] = { 194 "wlan_scan_sta", /* IEEE80211_M_IBSS */ 195 "wlan_scan_sta", /* IEEE80211_M_STA */ 196 "wlan_scan_wds", /* IEEE80211_M_WDS */ 197 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */ 198 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */ 199 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */ 200}; 201static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX]; 202 203const struct ieee80211_scanner * 204ieee80211_scanner_get(enum ieee80211_opmode mode) 205{ 206 if (mode >= IEEE80211_OPMODE_MAX) 207 return NULL; 208 if (scanners[mode] == NULL) 209 ieee80211_load_module(scan_modnames[mode]); 210 return scanners[mode]; 211} 212 213void 214ieee80211_scanner_register(enum ieee80211_opmode mode, 215 const struct ieee80211_scanner *scan) 216{ 217 if (mode >= IEEE80211_OPMODE_MAX) 218 return; 219 scanners[mode] = scan; 220} 221 222void 223ieee80211_scanner_unregister(enum ieee80211_opmode mode, 224 const struct ieee80211_scanner *scan) 225{ 226 if (mode >= IEEE80211_OPMODE_MAX) 227 return; 228 if (scanners[mode] == scan) 229 scanners[mode] = NULL; 230} 231 232void 233ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan) 234{ 235 int m; 236 237 for (m = 0; m < IEEE80211_OPMODE_MAX; m++) 238 if (scanners[m] == scan) 239 scanners[m] = NULL; 240} 241 242/* 243 * Update common scanner state to reflect the current 244 * operating mode. This is called when the state machine 245 * is transitioned to RUN state w/o scanning--e.g. when 246 * operating in monitor mode. The purpose of this is to 247 * ensure later callbacks find ss_ops set to properly 248 * reflect current operating mode. 249 */ 250static void 251scan_update_locked(struct ieee80211vap *vap, 252 const struct ieee80211_scanner *scan) 253{ 254 struct ieee80211com *ic = vap->iv_ic; 255 struct ieee80211_scan_state *ss = ic->ic_scan; 256 257 IEEE80211_LOCK_ASSERT(ic); 258 259#ifdef IEEE80211_DEBUG 260 if (ss->ss_vap != vap || ss->ss_ops != scan) { 261 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 262 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n", 263 __func__, 264 ss->ss_vap != NULL ? 265 ss->ss_vap->iv_ifp->if_xname : "none", 266 ss->ss_vap != NULL ? 267 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none", 268 vap->iv_ifp->if_xname, 269 ieee80211_opmode_name[vap->iv_opmode]); 270 } 271#endif 272 ss->ss_vap = vap; 273 if (ss->ss_ops != scan) { 274 /* 275 * Switch scanners; detach old, attach new. Special 276 * case where a single scan module implements multiple 277 * policies by using different scan ops but a common 278 * core. We assume if the old and new attach methods 279 * are identical then it's ok to just change ss_ops 280 * and not flush the internal state of the module. 281 */ 282 if (scan == NULL || ss->ss_ops == NULL || 283 ss->ss_ops->scan_attach != scan->scan_attach) { 284 if (ss->ss_ops != NULL) 285 ss->ss_ops->scan_detach(ss); 286 if (scan != NULL && !scan->scan_attach(ss)) { 287 /* XXX attach failure */ 288 /* XXX stat+msg */ 289 scan = NULL; 290 } 291 } 292 ss->ss_ops = scan; 293 } 294} 295 296static void 297change_channel(struct ieee80211com *ic, 298 struct ieee80211_channel *chan) 299{ 300 ic->ic_curchan = chan; 301 ic->ic_set_channel(ic); 302} 303 304static char 305channel_type(const struct ieee80211_channel *c) 306{ 307 if (IEEE80211_IS_CHAN_ST(c)) 308 return 'S'; 309 if (IEEE80211_IS_CHAN_108A(c)) 310 return 'T'; 311 if (IEEE80211_IS_CHAN_108G(c)) 312 return 'G'; 313 if (IEEE80211_IS_CHAN_HT(c)) 314 return 'n'; 315 if (IEEE80211_IS_CHAN_A(c)) 316 return 'a'; 317 if (IEEE80211_IS_CHAN_ANYG(c)) 318 return 'g'; 319 if (IEEE80211_IS_CHAN_B(c)) 320 return 'b'; 321 return 'f'; 322} 323 324void 325ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss) 326{ 327 struct ieee80211com *ic = ss->ss_vap->iv_ic; 328 const char *sep; 329 int i; 330 331 sep = ""; 332 for (i = ss->ss_next; i < ss->ss_last; i++) { 333 const struct ieee80211_channel *c = ss->ss_chans[i]; 334 335 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c), 336 channel_type(c)); 337 sep = ", "; 338 } 339} 340 341#ifdef IEEE80211_DEBUG 342static void 343scan_dump(struct ieee80211_scan_state *ss) 344{ 345 struct ieee80211vap *vap = ss->ss_vap; 346 347 if_printf(vap->iv_ifp, "scan set "); 348 ieee80211_scan_dump_channels(ss); 349 printf(" dwell min %lu max %lu\n", ss->ss_mindwell, ss->ss_maxdwell); 350} 351#endif /* IEEE80211_DEBUG */ 352 353/* 354 * Enable station power save mode and start/restart the scanning thread. 355 */ 356static void 357scan_restart_pwrsav(void *arg) 358{ 359 struct scan_state *ss = (struct scan_state *) arg; 360 struct ieee80211vap *vap = ss->base.ss_vap; 361 struct ieee80211com *ic = vap->iv_ic; 362 int ticksdelay; 363 364 ieee80211_sta_pwrsave(vap, 1); 365 /* 366 * Use an initial 1ms delay so the null 367 * data frame has a chance to go out. 368 * XXX 1ms is a lot, better to trigger scan 369 * on tx complete. 370 */ 371 ticksdelay = msecs_to_ticks(1); 372 if (ticksdelay < 1) 373 ticksdelay = 1; 374 ic->ic_scan_start(ic); /* notify driver */ 375 ss->ss_scanend = ticks + ticksdelay + ss->ss_duration; 376 ss->ss_iflags |= ISCAN_START; 377 callout_reset(&ss->ss_scan_timer, ticksdelay, scan_next, ss); 378} 379 380/* 381 * Start/restart scanning. If we're operating in station mode 382 * and associated notify the ap we're going into power save mode 383 * and schedule a callback to initiate the work (where there's a 384 * better context for doing the work). Otherwise, start the scan 385 * directly. 386 */ 387static int 388scan_restart(struct scan_state *ss, u_int duration) 389{ 390 struct ieee80211vap *vap = ss->base.ss_vap; 391 struct ieee80211com *ic = vap->iv_ic; 392 int defer = 0; 393 394 if (ss->base.ss_next == ss->base.ss_last) { 395 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 396 "%s: no channels to scan\n", __func__); 397 return 0; 398 } 399 if (vap->iv_opmode == IEEE80211_M_STA && 400 vap->iv_state == IEEE80211_S_RUN) { 401 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) { 402 /* 403 * Initiate power save before going off-channel. 404 * Note that we cannot do this directly because 405 * of locking issues; instead we defer it to a 406 * tasklet. 407 */ 408 ss->ss_duration = duration; 409 defer = 1; 410 } 411 } 412 413 if (!defer) { 414 ic->ic_scan_start(ic); /* notify driver */ 415 ss->ss_scanend = ticks + duration; 416 ss->ss_iflags |= ISCAN_START; 417 callout_reset(&ss->ss_scan_timer, 0, scan_next, ss); 418 } else 419 scan_restart_pwrsav(ss); 420 return 1; 421} 422 423static void 424copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss, 425 int nssid, const struct ieee80211_scan_ssid ssids[]) 426{ 427 if (nssid > IEEE80211_SCAN_MAX_SSID) { 428 /* XXX printf */ 429 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 430 "%s: too many ssid %d, ignoring all of them\n", 431 __func__, nssid); 432 return; 433 } 434 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0])); 435 ss->ss_nssid = nssid; 436} 437 438/* 439 * Start a scan unless one is already going. 440 */ 441static int 442start_scan_locked(const struct ieee80211_scanner *scan, 443 struct ieee80211vap *vap, int flags, u_int duration, 444 u_int mindwell, u_int maxdwell, 445 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 446{ 447 struct ieee80211com *ic = vap->iv_ic; 448 struct ieee80211_scan_state *ss = ic->ic_scan; 449 450 IEEE80211_LOCK_ASSERT(ic); 451 452 if (ic->ic_flags & IEEE80211_F_CSAPENDING) { 453 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 454 "%s: scan inhibited by pending channel change\n", __func__); 455 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) { 456 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 457 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n" 458 , __func__ 459 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive" 460 , duration, mindwell, maxdwell 461 , ieee80211_phymode_name[vap->iv_des_mode] 462 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append" 463 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : "" 464 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : "" 465 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : "" 466 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : "" 467 , flags & IEEE80211_SCAN_ONCE ? ", once" : "" 468 ); 469 470 scan_update_locked(vap, scan); 471 if (ss->ss_ops != NULL) { 472 if ((flags & IEEE80211_SCAN_NOSSID) == 0) 473 copy_ssid(vap, ss, nssid, ssids); 474 475 /* NB: top 4 bits for internal use */ 476 ss->ss_flags = flags & 0xfff; 477 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 478 vap->iv_stats.is_scan_active++; 479 else 480 vap->iv_stats.is_scan_passive++; 481 if (flags & IEEE80211_SCAN_FLUSH) 482 ss->ss_ops->scan_flush(ss); 483 484 /* NB: flush frames rx'd before 1st channel change */ 485 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 486 ss->ss_next = 0; 487 ss->ss_mindwell = mindwell; 488 ss->ss_maxdwell = maxdwell; 489 ss->ss_ops->scan_start(ss, vap); 490#ifdef IEEE80211_DEBUG 491 if (ieee80211_msg_scan(vap)) 492 scan_dump(ss); 493#endif /* IEEE80211_DEBUG */ 494 if (scan_restart(SCAN_PRIVATE(ss), duration)) 495 ic->ic_flags |= IEEE80211_F_SCAN; 496 } 497 } else { 498 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 499 "%s: %s scan already in progress\n", __func__, 500 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"); 501 } 502 return (ic->ic_flags & IEEE80211_F_SCAN); 503} 504 505/* 506 * Start a scan unless one is already going. 507 */ 508int 509ieee80211_start_scan(struct ieee80211vap *vap, int flags, 510 u_int duration, u_int mindwell, u_int maxdwell, 511 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 512{ 513 struct ieee80211com *ic = vap->iv_ic; 514 const struct ieee80211_scanner *scan; 515 int result; 516 517 scan = ieee80211_scanner_get(vap->iv_opmode); 518 if (scan == NULL) { 519 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 520 "%s: no scanner support for %s mode\n", 521 __func__, ieee80211_opmode_name[vap->iv_opmode]); 522 /* XXX stat */ 523 return 0; 524 } 525 526 IEEE80211_LOCK(ic); 527 result = start_scan_locked(scan, vap, flags, duration, 528 mindwell, maxdwell, nssid, ssids); 529 IEEE80211_UNLOCK(ic); 530 531 return result; 532} 533 534/* 535 * Check the scan cache for an ap/channel to use; if that 536 * fails then kick off a new scan. 537 */ 538int 539ieee80211_check_scan(struct ieee80211vap *vap, int flags, 540 u_int duration, u_int mindwell, u_int maxdwell, 541 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 542{ 543 struct ieee80211com *ic = vap->iv_ic; 544 struct ieee80211_scan_state *ss = ic->ic_scan; 545 const struct ieee80211_scanner *scan; 546 int result; 547 548 scan = ieee80211_scanner_get(vap->iv_opmode); 549 if (scan == NULL) { 550 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 551 "%s: no scanner support for %s mode\n", 552 __func__, vap->iv_opmode); 553 /* XXX stat */ 554 return 0; 555 } 556 557 /* 558 * Check if there's a list of scan candidates already. 559 * XXX want more than the ap we're currently associated with 560 */ 561 562 IEEE80211_LOCK(ic); 563 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 564 "%s: %s scan, %s%s%s%s%s\n" 565 , __func__ 566 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive" 567 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append" 568 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : "" 569 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : "" 570 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : "" 571 , flags & IEEE80211_SCAN_ONCE ? ", once" : "" 572 ); 573 574 if (ss->ss_ops != scan) { 575 /* XXX re-use cache contents? e.g. adhoc<->sta */ 576 flags |= IEEE80211_SCAN_FLUSH; 577 } 578 scan_update_locked(vap, scan); 579 if (ss->ss_ops != NULL) { 580 /* XXX verify ss_ops matches vap->iv_opmode */ 581 if ((flags & IEEE80211_SCAN_NOSSID) == 0) { 582 /* 583 * Update the ssid list and mark flags so if 584 * we call start_scan it doesn't duplicate work. 585 */ 586 copy_ssid(vap, ss, nssid, ssids); 587 flags |= IEEE80211_SCAN_NOSSID; 588 } 589 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 && 590 (flags & IEEE80211_SCAN_FLUSH) == 0 && 591 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 592 /* 593 * We're not currently scanning and the cache is 594 * deemed hot enough to consult. Lock out others 595 * by marking IEEE80211_F_SCAN while we decide if 596 * something is already in the scan cache we can 597 * use. Also discard any frames that might come 598 * in while temporarily marked as scanning. 599 */ 600 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 601 ic->ic_flags |= IEEE80211_F_SCAN; 602 603 /* NB: need to use supplied flags in check */ 604 ss->ss_flags = flags & 0xff; 605 result = ss->ss_ops->scan_end(ss, vap); 606 607 ic->ic_flags &= ~IEEE80211_F_SCAN; 608 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD; 609 if (result) { 610 ieee80211_notify_scan_done(vap); 611 IEEE80211_UNLOCK(ic); 612 return 1; 613 } 614 } 615 } 616 result = start_scan_locked(scan, vap, flags, duration, 617 mindwell, maxdwell, nssid, ssids); 618 IEEE80211_UNLOCK(ic); 619 620 return result; 621} 622 623/* 624 * Check the scan cache for an ap/channel to use; if that fails 625 * then kick off a scan using the current settings. 626 */ 627int 628ieee80211_check_scan_current(struct ieee80211vap *vap) 629{ 630 return ieee80211_check_scan(vap, 631 IEEE80211_SCAN_ACTIVE, 632 IEEE80211_SCAN_FOREVER, 0, 0, 633 vap->iv_des_nssid, vap->iv_des_ssid); 634} 635 636/* 637 * Restart a previous scan. If the previous scan completed 638 * then we start again using the existing channel list. 639 */ 640int 641ieee80211_bg_scan(struct ieee80211vap *vap, int flags) 642{ 643 struct ieee80211com *ic = vap->iv_ic; 644 struct ieee80211_scan_state *ss = ic->ic_scan; 645 const struct ieee80211_scanner *scan; 646 647 scan = ieee80211_scanner_get(vap->iv_opmode); 648 if (scan == NULL) { 649 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 650 "%s: no scanner support for %s mode\n", 651 __func__, vap->iv_opmode); 652 /* XXX stat */ 653 return 0; 654 } 655 656 IEEE80211_LOCK(ic); 657 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) { 658 u_int duration; 659 /* 660 * Go off-channel for a fixed interval that is large 661 * enough to catch most ap's but short enough that 662 * we can return on-channel before our listen interval 663 * expires. 664 */ 665 duration = IEEE80211_SCAN_OFFCHANNEL; 666 667 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 668 "%s: %s scan, ticks %u duration %lu\n", __func__, 669 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive", 670 ticks, duration); 671 672 scan_update_locked(vap, scan); 673 if (ss->ss_ops != NULL) { 674 ss->ss_vap = vap; 675 /* 676 * A background scan does not select a new sta; it 677 * just refreshes the scan cache. Also, indicate 678 * the scan logic should follow the beacon schedule: 679 * we go off-channel and scan for a while, then 680 * return to the bss channel to receive a beacon, 681 * then go off-channel again. All during this time 682 * we notify the ap we're in power save mode. When 683 * the scan is complete we leave power save mode. 684 * If any beacon indicates there are frames pending 685 * for us then we drop out of power save mode 686 * (and background scan) automatically by way of the 687 * usual sta power save logic. 688 */ 689 ss->ss_flags |= IEEE80211_SCAN_NOPICK 690 | IEEE80211_SCAN_BGSCAN 691 | flags 692 ; 693 /* if previous scan completed, restart */ 694 if (ss->ss_next >= ss->ss_last) { 695 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 696 vap->iv_stats.is_scan_active++; 697 else 698 vap->iv_stats.is_scan_passive++; 699 /* 700 * NB: beware of the scan cache being flushed; 701 * if the channel list is empty use the 702 * scan_start method to populate it. 703 */ 704 ss->ss_next = 0; 705 if (ss->ss_last != 0) 706 ss->ss_ops->scan_restart(ss, vap); 707 else { 708 ss->ss_ops->scan_start(ss, vap); 709#ifdef IEEE80211_DEBUG 710 if (ieee80211_msg_scan(vap)) 711 scan_dump(ss); 712#endif /* IEEE80211_DEBUG */ 713 } 714 } 715 /* NB: flush frames rx'd before 1st channel change */ 716 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 717 ss->ss_maxdwell = duration; 718 if (scan_restart(SCAN_PRIVATE(ss), duration)) { 719 ic->ic_flags |= IEEE80211_F_SCAN; 720 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN; 721 } 722 } else { 723 /* XXX msg+stat */ 724 } 725 } else { 726 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 727 "%s: %s scan already in progress\n", __func__, 728 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"); 729 } 730 IEEE80211_UNLOCK(ic); 731 732 /* NB: racey, does it matter? */ 733 return (ic->ic_flags & IEEE80211_F_SCAN); 734} 735 736/* 737 * Cancel any scan currently going on for the specified vap. 738 */ 739void 740ieee80211_cancel_scan(struct ieee80211vap *vap) 741{ 742 struct ieee80211com *ic = vap->iv_ic; 743 struct ieee80211_scan_state *ss = ic->ic_scan; 744 745 IEEE80211_LOCK(ic); 746 if ((ic->ic_flags & IEEE80211_F_SCAN) && 747 ss->ss_vap == vap && 748 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) { 749 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 750 "%s: cancel %s scan\n", __func__, 751 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? 752 "active" : "passive"); 753 754 /* clear bg scan NOPICK and mark cancel request */ 755 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 756 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL; 757 /* force it to fire asap */ 758 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 759 0, scan_next, ss); 760 } 761 IEEE80211_UNLOCK(ic); 762} 763 764/* 765 * Cancel any scan currently going on. 766 */ 767void 768ieee80211_cancel_anyscan(struct ieee80211vap *vap) 769{ 770 struct ieee80211com *ic = vap->iv_ic; 771 struct ieee80211_scan_state *ss = ic->ic_scan; 772 773 IEEE80211_LOCK(ic); 774 if ((ic->ic_flags & IEEE80211_F_SCAN) && 775 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) { 776 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 777 "%s: cancel %s scan\n", __func__, 778 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? 779 "active" : "passive"); 780 781 /* clear bg scan NOPICK and mark cancel request */ 782 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 783 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL; 784 /* force it to fire asap */ 785 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 786 0, scan_next, ss); 787 } 788 IEEE80211_UNLOCK(ic); 789} 790 791/* 792 * Public access to scan_next for drivers that manage 793 * scanning themselves (e.g. for firmware-based devices). 794 */ 795void 796ieee80211_scan_next(struct ieee80211vap *vap) 797{ 798 struct ieee80211com *ic = vap->iv_ic; 799 struct ieee80211_scan_state *ss = ic->ic_scan; 800 801 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss); 802} 803 804/* 805 * Public access to scan_next for drivers that are not able to scan single 806 * channels (e.g. for firmware-based devices). 807 */ 808void 809ieee80211_scan_done(struct ieee80211vap *vap) 810{ 811 struct ieee80211com *ic = vap->iv_ic; 812 struct ieee80211_scan_state *ss; 813 814 IEEE80211_LOCK(ic); 815 ss = ic->ic_scan; 816 ss->ss_next = ss->ss_last; /* all channels are complete */ 817 scan_next(ss); 818 IEEE80211_UNLOCK(ic); 819} 820 821/* 822 * Probe the curent channel, if allowed, while scanning. 823 * If the channel is not marked passive-only then send 824 * a probe request immediately. Otherwise mark state and 825 * listen for beacons on the channel; if we receive something 826 * then we'll transmit a probe request. 827 */ 828void 829ieee80211_probe_curchan(struct ieee80211vap *vap, int force) 830{ 831 struct ieee80211com *ic = vap->iv_ic; 832 struct ieee80211_scan_state *ss = ic->ic_scan; 833 struct ifnet *ifp = vap->iv_ifp; 834 int i; 835 836 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) { 837 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN; 838 return; 839 } 840 /* 841 * Send directed probe requests followed by any 842 * broadcast probe request. 843 * XXX remove dependence on ic/vap->iv_bss 844 */ 845 for (i = 0; i < ss->ss_nssid; i++) 846 ieee80211_send_probereq(vap->iv_bss, 847 vap->iv_myaddr, ifp->if_broadcastaddr, 848 ifp->if_broadcastaddr, 849 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len); 850 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0) 851 ieee80211_send_probereq(vap->iv_bss, 852 vap->iv_myaddr, ifp->if_broadcastaddr, 853 ifp->if_broadcastaddr, 854 "", 0); 855} 856 857/* 858 * Scan curchan. If this is an active scan and the channel 859 * is not marked passive then send probe request frame(s). 860 * Arrange for the channel change after maxdwell ticks. 861 */ 862static void 863scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell) 864{ 865 struct ieee80211vap *vap = ss->ss_vap; 866 867 IEEE80211_LOCK_ASSERT(vap->iv_ic); 868 869 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 870 ieee80211_probe_curchan(vap, 0); 871 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 872 maxdwell, scan_next, ss); 873} 874 875/* 876 * Handle mindwell requirements completed; initiate a channel 877 * change to the next channel asap. 878 */ 879static void 880scan_mindwell(struct ieee80211_scan_state *ss) 881{ 882 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 0, scan_next, ss); 883} 884 885/* 886 * Switch to the next channel marked for scanning. 887 */ 888static void 889scan_next(void *arg) 890{ 891#define ISCAN_REP (ISCAN_MINDWELL | ISCAN_START | ISCAN_DISCARD) 892 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg; 893 struct ieee80211vap *vap = ss->ss_vap; 894 struct ieee80211com *ic = vap->iv_ic; 895 struct ieee80211_channel *chan; 896 unsigned long maxdwell, scanend; 897 int scandone; 898 899 IEEE80211_LOCK_ASSERT(ic); 900 901 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) 902 return; 903again: 904 scandone = (ss->ss_next >= ss->ss_last) || 905 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0; 906 scanend = SCAN_PRIVATE(ss)->ss_scanend; 907 if (!scandone && 908 (ss->ss_flags & IEEE80211_SCAN_GOTPICK) == 0 && 909 ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_START) || 910 time_before(ticks + ss->ss_mindwell, scanend))) { 911 chan = ss->ss_chans[ss->ss_next++]; 912 913 /* 914 * Watch for truncation due to the scan end time. 915 */ 916 if (time_after(ticks + ss->ss_maxdwell, scanend)) 917 maxdwell = scanend - ticks; 918 else 919 maxdwell = ss->ss_maxdwell; 920 921 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 922 "%s: chan %3d%c -> %3d%c [%s, dwell min %lu max %lu]\n", 923 __func__, 924 ieee80211_chan2ieee(ic, ic->ic_curchan), 925 channel_type(ic->ic_curchan), 926 ieee80211_chan2ieee(ic, chan), channel_type(chan), 927 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) && 928 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ? 929 "active" : "passive", 930 ss->ss_mindwell, maxdwell); 931 932 /* 933 * Potentially change channel and phy mode. 934 */ 935 change_channel(ic, chan); 936 937 /* 938 * Scan curchan. Drivers for "intelligent hardware" 939 * override ic_scan_curchan to tell the device to do 940 * the work. Otherwise we manage the work outselves; 941 * sending a probe request (as needed), and arming the 942 * timeout to switch channels after maxdwell ticks. 943 */ 944 ic->ic_scan_curchan(ss, maxdwell); 945 946 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell; 947 /* clear mindwell lock and initial channel change flush */ 948 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP; 949 } else { 950 ic->ic_scan_end(ic); /* notify driver */ 951 /* 952 * Record scan complete time. Note that we also do 953 * this when canceled so any background scan will 954 * not be restarted for a while. 955 */ 956 if (scandone) 957 ic->ic_lastscan = ticks; 958 /* return to the bss channel */ 959 if (ic->ic_bsschan != IEEE80211_CHAN_ANYC && 960 ic->ic_curchan != ic->ic_bsschan) 961 ieee80211_setcurchan(ic, ic->ic_bsschan); 962 /* clear internal flags and any indication of a pick */ 963 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP; 964 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK; 965 966 /* 967 * If not canceled and scan completed, do post-processing. 968 * If the callback function returns 0, then it wants to 969 * continue/restart scanning. Unfortunately we needed to 970 * notify the driver to end the scan above to avoid having 971 * rx frames alter the scan candidate list. 972 */ 973 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 && 974 !ss->ss_ops->scan_end(ss, vap) && 975 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 && 976 time_before(ticks + ss->ss_mindwell, scanend)) { 977 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 978 "%s: done, restart " 979 "[ticks %u, dwell min %lu scanend %lu]\n", 980 __func__, 981 ticks, ss->ss_mindwell, scanend); 982 ss->ss_next = 0; /* reset to begining */ 983 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 984 vap->iv_stats.is_scan_active++; 985 else 986 vap->iv_stats.is_scan_passive++; 987 988 ss->ss_ops->scan_restart(ss, vap); /* XXX? */ 989 ic->ic_scan_start(ic); /* notify driver */ 990 goto again; 991 } else { 992 /* past here, scandone is ``true'' if not in bg mode */ 993 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0) 994 scandone = 1; 995 996 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 997 "%s: %s, " 998 "[ticks %u, dwell min %lu scanend %lu]\n", 999 __func__, scandone ? "done" : "stopped", 1000 ticks, ss->ss_mindwell, scanend); 1001 1002 /* 1003 * Clear the SCAN bit first in case frames are 1004 * pending on the station power save queue. If 1005 * we defer this then the dispatch of the frames 1006 * may generate a request to cancel scanning. 1007 */ 1008 ic->ic_flags &= ~IEEE80211_F_SCAN; 1009 /* 1010 * Drop out of power save mode when a scan has 1011 * completed. If this scan was prematurely terminated 1012 * because it is a background scan then don't notify 1013 * the ap; we'll either return to scanning after we 1014 * receive the beacon frame or we'll drop out of power 1015 * save mode because the beacon indicates we have frames 1016 * waiting for us. 1017 */ 1018 if (scandone) { 1019 ieee80211_sta_pwrsave(vap, 0); 1020 if (ss->ss_next >= ss->ss_last) { 1021 ieee80211_notify_scan_done(vap); 1022 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN; 1023 } 1024 } 1025 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_CANCEL; 1026 ss->ss_flags &= 1027 ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST); 1028 } 1029 } 1030#undef ISCAN_REP 1031} 1032 1033#ifdef IEEE80211_DEBUG 1034static void 1035dump_country(const uint8_t *ie) 1036{ 1037 const struct ieee80211_country_ie *cie = 1038 (const struct ieee80211_country_ie *) ie; 1039 int i, nbands, schan, nchan; 1040 1041 if (cie->len < 3) { 1042 printf(" <bogus country ie, len %d>", cie->len); 1043 return; 1044 } 1045 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]); 1046 nbands = (cie->len - 3) / sizeof(cie->band[0]); 1047 for (i = 0; i < nbands; i++) { 1048 schan = cie->band[i].schan; 1049 nchan = cie->band[i].nchan; 1050 if (nchan != 1) 1051 printf(" %u-%u,%u", schan, schan + nchan-1, 1052 cie->band[i].maxtxpwr); 1053 else 1054 printf(" %u,%u", schan, cie->band[i].maxtxpwr); 1055 } 1056 printf("]"); 1057} 1058 1059static void 1060dump_probe_beacon(uint8_t subtype, int isnew, 1061 const uint8_t mac[IEEE80211_ADDR_LEN], 1062 const struct ieee80211_scanparams *sp, int rssi) 1063{ 1064 1065 printf("[%s] %s%s on chan %u (bss chan %u) ", 1066 ether_sprintf(mac), isnew ? "new " : "", 1067 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT], 1068 sp->chan, sp->bchan); 1069 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]); 1070 printf(" rssi %d\n", rssi); 1071 1072 if (isnew) { 1073 printf("[%s] caps 0x%x bintval %u erp 0x%x", 1074 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp); 1075 if (sp->country != NULL) 1076 dump_country(sp->country); 1077 printf("\n"); 1078 } 1079} 1080#endif /* IEEE80211_DEBUG */ 1081 1082/* 1083 * Process a beacon or probe response frame. 1084 */ 1085void 1086ieee80211_add_scan(struct ieee80211vap *vap, 1087 const struct ieee80211_scanparams *sp, 1088 const struct ieee80211_frame *wh, 1089 int subtype, int rssi, int noise, int rstamp) 1090{ 1091 struct ieee80211com *ic = vap->iv_ic; 1092 struct ieee80211_scan_state *ss = ic->ic_scan; 1093 1094 /* XXX locking */ 1095 /* 1096 * Frames received during startup are discarded to avoid 1097 * using scan state setup on the initial entry to the timer 1098 * callback. This can occur because the device may enable 1099 * rx prior to our doing the initial channel change in the 1100 * timer routine. 1101 */ 1102 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD) 1103 return; 1104#ifdef IEEE80211_DEBUG 1105 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN)) 1106 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi); 1107#endif 1108 if (ss->ss_ops != NULL && 1109 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise, rstamp)) { 1110 /* 1111 * If we've reached the min dwell time terminate 1112 * the timer so we'll switch to the next channel. 1113 */ 1114 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 && 1115 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) { 1116 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1117 "%s: chan %3d%c min dwell met (%u > %lu)\n", 1118 __func__, 1119 ieee80211_chan2ieee(ic, ic->ic_curchan), 1120 channel_type(ic->ic_curchan), 1121 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell); 1122 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL; 1123 /* 1124 * NB: trigger at next clock tick or wait for the 1125 * hardware. 1126 */ 1127 ic->ic_scan_mindwell(ss); 1128 } 1129 } 1130} 1131 1132/* 1133 * Timeout/age scan cache entries; called from sta timeout 1134 * timer (XXX should be self-contained). 1135 */ 1136void 1137ieee80211_scan_timeout(struct ieee80211com *ic) 1138{ 1139 struct ieee80211_scan_state *ss = ic->ic_scan; 1140 1141 if (ss->ss_ops != NULL) 1142 ss->ss_ops->scan_age(ss); 1143} 1144 1145/* 1146 * Mark a scan cache entry after a successful associate. 1147 */ 1148void 1149ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[]) 1150{ 1151 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1152 1153 if (ss->ss_ops != NULL) { 1154 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, 1155 mac, "%s", __func__); 1156 ss->ss_ops->scan_assoc_success(ss, mac); 1157 } 1158} 1159 1160/* 1161 * Demerit a scan cache entry after failing to associate. 1162 */ 1163void 1164ieee80211_scan_assoc_fail(struct ieee80211vap *vap, 1165 const uint8_t mac[], int reason) 1166{ 1167 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1168 1169 if (ss->ss_ops != NULL) { 1170 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac, 1171 "%s: reason %u", __func__, reason); 1172 ss->ss_ops->scan_assoc_fail(ss, mac, reason); 1173 } 1174} 1175 1176/* 1177 * Iterate over the contents of the scan cache. 1178 */ 1179void 1180ieee80211_scan_iterate(struct ieee80211vap *vap, 1181 ieee80211_scan_iter_func *f, void *arg) 1182{ 1183 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1184 1185 if (ss->ss_ops != NULL) 1186 ss->ss_ops->scan_iterate(ss, f, arg); 1187} 1188 1189/* 1190 * Flush the contents of the scan cache. 1191 */ 1192void 1193ieee80211_scan_flush(struct ieee80211vap *vap) 1194{ 1195 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1196 1197 if (ss->ss_ops != NULL && ss->ss_vap == vap) { 1198 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__); 1199 ss->ss_ops->scan_flush(ss); 1200 } 1201} 1202 1203/* 1204 * Check the scan cache for an ap/channel to use; if that 1205 * fails then kick off a new scan. 1206 */ 1207struct ieee80211_channel * 1208ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags) 1209{ 1210 struct ieee80211_scan_state *ss = ic->ic_scan; 1211 1212 IEEE80211_LOCK_ASSERT(ic); 1213 1214 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) { 1215 /* XXX printf? */ 1216 return NULL; 1217 } 1218 if (ss->ss_ops->scan_pickchan == NULL) { 1219 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN, 1220 "%s: scan module does not support picking a channel, " 1221 "opmode %s\n", __func__, ss->ss_vap->iv_opmode); 1222 return NULL; 1223 } 1224 return ss->ss_ops->scan_pickchan(ss, flags); 1225} 1226