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 * $FreeBSD: head/sys/net80211/ieee80211_scan.c 195618 2009-07-11 15:02:45Z rpaulo $ 26 */ 27 28 /* 29 * IEEE 802.11 scanning support. 30 */ 31 #include "opt_wlan.h" 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/proc.h> 36 #include <sys/kernel.h> 37 38 #include <sys/condvar.h> 39 #include <sys/socket.h> 40 41 #include <net/if.h> 42 #include <net/if_media.h> 43 #include <net/ethernet.h> 44 #include <net/route.h> 45 46 #include <netproto/802_11/ieee80211_var.h> 47 48 #include <net/bpf.h> 49 50 struct scan_state { 51 struct ieee80211_scan_state base; /* public state */ 52 53 u_int ss_iflags; /* flags used internally */ 54 #define ISCAN_MINDWELL 0x0001 /* min dwell time reached */ 55 #define ISCAN_DISCARD 0x0002 /* discard rx'd frames */ 56 #define ISCAN_CANCEL 0x0004 /* cancel current scan */ 57 #define ISCAN_ABORT 0x0008 /* end the scan immediately */ 58 unsigned long ss_chanmindwell; /* min dwell on curchan */ 59 unsigned long ss_scanend; /* time scan must stop */ 60 u_int ss_duration; /* duration for next scan */ 61 struct task ss_scan_task; /* scan execution */ 62 struct cv ss_scan_cv; /* scan signal */ 63 struct callout ss_scan_timer; /* scan timer */ 64 }; 65 #define SCAN_PRIVATE(ss) ((struct scan_state *) ss) 66 67 /* 68 * Amount of time to go off-channel during a background 69 * scan. This value should be large enough to catch most 70 * ap's but short enough that we can return on-channel 71 * before our listen interval expires. 72 * 73 * XXX tunable 74 * XXX check against configured listen interval 75 */ 76 #define IEEE80211_SCAN_OFFCHANNEL msecs_to_ticks(150) 77 78 /* 79 * Roaming-related defaults. RSSI thresholds are as returned by the 80 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e 81 * .5M units) or MCS. 82 */ 83 /* rssi thresholds */ 84 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */ 85 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */ 86 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */ 87 /* transmit rate thresholds */ 88 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */ 89 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */ 90 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */ 91 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */ 92 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */ 93 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */ 94 95 static void scan_curchan(struct ieee80211_scan_state *, unsigned long); 96 static void scan_mindwell(struct ieee80211_scan_state *); 97 static void scan_signal_callout(void *); 98 static void scan_signal(struct ieee80211_scan_state *ss); 99 static void scan_task(void *, int); 100 101 MALLOC_DEFINE(M_80211_SCAN, "80211scan", "802.11 scan state"); 102 103 void 104 ieee80211_scan_attach(struct ieee80211com *ic) 105 { 106 struct scan_state *ss; 107 108 ss = (struct scan_state *) kmalloc(sizeof(struct scan_state), 109 M_80211_SCAN, M_INTWAIT | M_ZERO); 110 if (ss == NULL) { 111 ic->ic_scan = NULL; 112 return; 113 } 114 wlan_cv_init(&ss->ss_scan_cv, "scan"); 115 callout_init(&ss->ss_scan_timer); 116 TASK_INIT(&ss->ss_scan_task, 0, scan_task, ss); 117 ic->ic_scan = &ss->base; 118 ss->base.ss_ic = ic; 119 120 ic->ic_scan_curchan = scan_curchan; 121 ic->ic_scan_mindwell = scan_mindwell; 122 } 123 124 void 125 ieee80211_scan_detach(struct ieee80211com *ic) 126 { 127 struct ieee80211_scan_state *ss = ic->ic_scan; 128 129 if (ss != NULL) { 130 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT; 131 scan_signal(ss); 132 ieee80211_draintask(ic, &SCAN_PRIVATE(ss)->ss_scan_task); 133 callout_stop(&SCAN_PRIVATE(ss)->ss_scan_timer); 134 KASSERT((ic->ic_flags & IEEE80211_F_SCAN) == 0, 135 ("scan still running")); 136 if (ss->ss_ops != NULL) { 137 ss->ss_ops->scan_detach(ss); 138 ss->ss_ops = NULL; 139 } 140 ic->ic_scan = NULL; 141 kfree(SCAN_PRIVATE(ss), M_80211_SCAN); 142 } 143 } 144 145 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = { 146 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT, 147 .rate = ROAM_RATE_11A_DEFAULT }, 148 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT, 149 .rate = ROAM_RATE_11B_DEFAULT }, 150 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT, 151 .rate = ROAM_RATE_11BONLY_DEFAULT }, 152 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT, 153 .rate = ROAM_RATE_11A_DEFAULT }, 154 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT, 155 .rate = ROAM_RATE_11A_DEFAULT }, 156 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT, 157 .rate = ROAM_RATE_11A_DEFAULT }, 158 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT, 159 .rate = ROAM_RATE_HALF_DEFAULT }, 160 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT, 161 .rate = ROAM_RATE_QUARTER_DEFAULT }, 162 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT, 163 .rate = ROAM_MCS_11N_DEFAULT }, 164 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT, 165 .rate = ROAM_MCS_11N_DEFAULT }, 166 }; 167 168 void 169 ieee80211_scan_vattach(struct ieee80211vap *vap) 170 { 171 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz; 172 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz; 173 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz; 174 175 vap->iv_roaming = IEEE80211_ROAMING_AUTO; 176 memcpy(vap->iv_roamparms, defroam, sizeof(defroam)); 177 } 178 179 void 180 ieee80211_scan_vdetach(struct ieee80211vap *vap) 181 { 182 struct ieee80211com *ic = vap->iv_ic; 183 struct ieee80211_scan_state *ss; 184 185 ss = ic->ic_scan; 186 if (ss != NULL && ss->ss_vap == vap) { 187 if (ic->ic_flags & IEEE80211_F_SCAN) { 188 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_ABORT; 189 scan_signal(ss); 190 } 191 if (ss->ss_ops != NULL) { 192 ss->ss_ops->scan_detach(ss); 193 ss->ss_ops = NULL; 194 } 195 ss->ss_vap = NULL; 196 } 197 } 198 199 /* 200 * Simple-minded scanner module support. 201 */ 202 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = { 203 "wlan_scan_sta", /* IEEE80211_M_IBSS */ 204 "wlan_scan_sta", /* IEEE80211_M_STA */ 205 "wlan_scan_wds", /* IEEE80211_M_WDS */ 206 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */ 207 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */ 208 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */ 209 "wlan_scan_sta", /* IEEE80211_M_MBSS */ 210 }; 211 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX]; 212 213 const struct ieee80211_scanner * 214 ieee80211_scanner_get(enum ieee80211_opmode mode) 215 { 216 if (mode >= IEEE80211_OPMODE_MAX) 217 return NULL; 218 if (scanners[mode] == NULL) 219 ieee80211_load_module(scan_modnames[mode]); 220 return scanners[mode]; 221 } 222 223 void 224 ieee80211_scanner_register(enum ieee80211_opmode mode, 225 const struct ieee80211_scanner *scan) 226 { 227 if (mode >= IEEE80211_OPMODE_MAX) 228 return; 229 scanners[mode] = scan; 230 } 231 232 void 233 ieee80211_scanner_unregister(enum ieee80211_opmode mode, 234 const struct ieee80211_scanner *scan) 235 { 236 if (mode >= IEEE80211_OPMODE_MAX) 237 return; 238 if (scanners[mode] == scan) 239 scanners[mode] = NULL; 240 } 241 242 void 243 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan) 244 { 245 int m; 246 247 for (m = 0; m < IEEE80211_OPMODE_MAX; m++) 248 if (scanners[m] == scan) 249 scanners[m] = NULL; 250 } 251 252 /* 253 * Update common scanner state to reflect the current 254 * operating mode. This is called when the state machine 255 * is transitioned to RUN state w/o scanning--e.g. when 256 * operating in monitor mode. The purpose of this is to 257 * ensure later callbacks find ss_ops set to properly 258 * reflect current operating mode. 259 */ 260 static void 261 scan_update_locked(struct ieee80211vap *vap, 262 const struct ieee80211_scanner *scan) 263 { 264 struct ieee80211com *ic = vap->iv_ic; 265 struct ieee80211_scan_state *ss = ic->ic_scan; 266 267 #ifdef IEEE80211_DEBUG 268 if (ss->ss_vap != vap || ss->ss_ops != scan) { 269 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 270 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n", 271 __func__, 272 ss->ss_vap != NULL ? 273 ss->ss_vap->iv_ifp->if_xname : "none", 274 ss->ss_vap != NULL ? 275 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none", 276 vap->iv_ifp->if_xname, 277 ieee80211_opmode_name[vap->iv_opmode]); 278 } 279 #endif 280 ss->ss_vap = vap; 281 if (ss->ss_ops != scan) { 282 /* 283 * Switch scanners; detach old, attach new. Special 284 * case where a single scan module implements multiple 285 * policies by using different scan ops but a common 286 * core. We assume if the old and new attach methods 287 * are identical then it's ok to just change ss_ops 288 * and not flush the internal state of the module. 289 */ 290 if (scan == NULL || ss->ss_ops == NULL || 291 ss->ss_ops->scan_attach != scan->scan_attach) { 292 if (ss->ss_ops != NULL) 293 ss->ss_ops->scan_detach(ss); 294 if (scan != NULL && !scan->scan_attach(ss)) { 295 /* XXX attach failure */ 296 /* XXX stat+msg */ 297 scan = NULL; 298 } 299 } 300 ss->ss_ops = scan; 301 } 302 } 303 304 static char 305 channel_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 } 323 324 void 325 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss) 326 { 327 struct ieee80211com *ic = ss->ss_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 kprintf("%s%u%c", sep, ieee80211_chan2ieee(ic, c), 336 channel_type(c)); 337 sep = ", "; 338 } 339 } 340 341 #ifdef IEEE80211_DEBUG 342 static void 343 scan_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 kprintf(" dwell min %lums max %lums\n", 350 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell)); 351 } 352 #endif /* IEEE80211_DEBUG */ 353 354 static void 355 copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss, 356 int nssid, const struct ieee80211_scan_ssid ssids[]) 357 { 358 if (nssid > IEEE80211_SCAN_MAX_SSID) { 359 /* XXX printf */ 360 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 361 "%s: too many ssid %d, ignoring all of them\n", 362 __func__, nssid); 363 return; 364 } 365 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0])); 366 ss->ss_nssid = nssid; 367 } 368 369 /* 370 * Start a scan unless one is already going. 371 */ 372 static int 373 start_scan_locked(const struct ieee80211_scanner *scan, 374 struct ieee80211vap *vap, int flags, u_int duration, 375 u_int mindwell, u_int maxdwell, 376 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 377 { 378 struct ieee80211com *ic = vap->iv_ic; 379 struct ieee80211_scan_state *ss = ic->ic_scan; 380 381 if (ic->ic_flags & IEEE80211_F_CSAPENDING) { 382 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 383 "%s: scan inhibited by pending channel change\n", __func__); 384 } else if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) { 385 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 386 "%s: %s scan, duration %u mindwell %u maxdwell %u, desired mode %s, %s%s%s%s%s%s\n" 387 , __func__ 388 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive" 389 , duration, mindwell, maxdwell 390 , ieee80211_phymode_name[vap->iv_des_mode] 391 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append" 392 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : "" 393 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : "" 394 , flags & IEEE80211_SCAN_NOBCAST ? ", nobcast" : "" 395 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : "" 396 , flags & IEEE80211_SCAN_ONCE ? ", once" : "" 397 ); 398 399 scan_update_locked(vap, scan); 400 if (ss->ss_ops != NULL) { 401 if ((flags & IEEE80211_SCAN_NOSSID) == 0) 402 copy_ssid(vap, ss, nssid, ssids); 403 404 /* NB: top 4 bits for internal use */ 405 ss->ss_flags = flags & 0xfff; 406 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 407 vap->iv_stats.is_scan_active++; 408 else 409 vap->iv_stats.is_scan_passive++; 410 if (flags & IEEE80211_SCAN_FLUSH) 411 ss->ss_ops->scan_flush(ss); 412 413 /* NB: flush frames rx'd before 1st channel change */ 414 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 415 SCAN_PRIVATE(ss)->ss_duration = duration; 416 ss->ss_next = 0; 417 ss->ss_mindwell = mindwell; 418 ss->ss_maxdwell = maxdwell; 419 /* NB: scan_start must be before the scan runtask */ 420 ss->ss_ops->scan_start(ss, vap); 421 #ifdef IEEE80211_DEBUG 422 if (ieee80211_msg_scan(vap)) 423 scan_dump(ss); 424 #endif /* IEEE80211_DEBUG */ 425 ic->ic_flags |= IEEE80211_F_SCAN; 426 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task); 427 } 428 } else { 429 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 430 "%s: %s scan already in progress\n", __func__, 431 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"); 432 } 433 return (ic->ic_flags & IEEE80211_F_SCAN); 434 } 435 436 /* 437 * Start a scan unless one is already going. 438 */ 439 int 440 ieee80211_start_scan(struct ieee80211vap *vap, int flags, 441 u_int duration, u_int mindwell, u_int maxdwell, 442 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 443 { 444 const struct ieee80211_scanner *scan; 445 int result; 446 447 scan = ieee80211_scanner_get(vap->iv_opmode); 448 if (scan == NULL) { 449 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 450 "%s: no scanner support for %s mode\n", 451 __func__, ieee80211_opmode_name[vap->iv_opmode]); 452 /* XXX stat */ 453 return 0; 454 } 455 456 result = start_scan_locked(scan, vap, flags, duration, 457 mindwell, maxdwell, nssid, ssids); 458 459 return result; 460 } 461 462 /* 463 * Check the scan cache for an ap/channel to use; if that 464 * fails then kick off a new scan. 465 */ 466 int 467 ieee80211_check_scan(struct ieee80211vap *vap, int flags, 468 u_int duration, u_int mindwell, u_int maxdwell, 469 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 470 { 471 struct ieee80211com *ic = vap->iv_ic; 472 struct ieee80211_scan_state *ss = ic->ic_scan; 473 const struct ieee80211_scanner *scan; 474 int result; 475 476 scan = ieee80211_scanner_get(vap->iv_opmode); 477 if (scan == NULL) { 478 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 479 "%s: no scanner support for %d mode\n", 480 __func__, vap->iv_opmode); 481 /* XXX stat */ 482 return 0; 483 } 484 485 /* 486 * Check if there's a list of scan candidates already. 487 * XXX want more than the ap we're currently associated with 488 */ 489 490 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 491 "%s: %s scan, %s%s%s%s%s\n" 492 , __func__ 493 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive" 494 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append" 495 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : "" 496 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : "" 497 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : "" 498 , flags & IEEE80211_SCAN_ONCE ? ", once" : "" 499 ); 500 501 if (ss->ss_ops != scan) { 502 /* XXX re-use cache contents? e.g. adhoc<->sta */ 503 flags |= IEEE80211_SCAN_FLUSH; 504 } 505 scan_update_locked(vap, scan); 506 if (ss->ss_ops != NULL) { 507 /* XXX verify ss_ops matches vap->iv_opmode */ 508 if ((flags & IEEE80211_SCAN_NOSSID) == 0) { 509 /* 510 * Update the ssid list and mark flags so if 511 * we call start_scan it doesn't duplicate work. 512 */ 513 copy_ssid(vap, ss, nssid, ssids); 514 flags |= IEEE80211_SCAN_NOSSID; 515 } 516 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0 && 517 (flags & IEEE80211_SCAN_FLUSH) == 0 && 518 time_before(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { 519 /* 520 * We're not currently scanning and the cache is 521 * deemed hot enough to consult. Lock out others 522 * by marking IEEE80211_F_SCAN while we decide if 523 * something is already in the scan cache we can 524 * use. Also discard any frames that might come 525 * in while temporarily marked as scanning. 526 */ 527 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 528 ic->ic_flags |= IEEE80211_F_SCAN; 529 530 /* NB: need to use supplied flags in check */ 531 ss->ss_flags = flags & 0xff; 532 result = ss->ss_ops->scan_end(ss, vap); 533 534 ic->ic_flags &= ~IEEE80211_F_SCAN; 535 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_DISCARD; 536 if (result) { 537 ieee80211_notify_scan_done(vap); 538 return 1; 539 } 540 } 541 } 542 result = start_scan_locked(scan, vap, flags, duration, 543 mindwell, maxdwell, nssid, ssids); 544 545 return result; 546 } 547 548 /* 549 * Check the scan cache for an ap/channel to use; if that fails 550 * then kick off a scan using the current settings. 551 */ 552 int 553 ieee80211_check_scan_current(struct ieee80211vap *vap) 554 { 555 return ieee80211_check_scan(vap, 556 IEEE80211_SCAN_ACTIVE, 557 IEEE80211_SCAN_FOREVER, 0, 0, 558 vap->iv_des_nssid, vap->iv_des_ssid); 559 } 560 561 /* 562 * Restart a previous scan. If the previous scan completed 563 * then we start again using the existing channel list. 564 */ 565 int 566 ieee80211_bg_scan(struct ieee80211vap *vap, int flags) 567 { 568 struct ieee80211com *ic = vap->iv_ic; 569 struct ieee80211_scan_state *ss = ic->ic_scan; 570 const struct ieee80211_scanner *scan; 571 572 scan = ieee80211_scanner_get(vap->iv_opmode); 573 if (scan == NULL) { 574 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 575 "%s: no scanner support for %d mode\n", 576 __func__, vap->iv_opmode); 577 /* XXX stat */ 578 return 0; 579 } 580 581 if ((ic->ic_flags & IEEE80211_F_SCAN) == 0) { 582 u_int duration; 583 /* 584 * Go off-channel for a fixed interval that is large 585 * enough to catch most ap's but short enough that 586 * we can return on-channel before our listen interval 587 * expires. 588 */ 589 duration = IEEE80211_SCAN_OFFCHANNEL; 590 591 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 592 "%s: %s scan, ticks %u duration %u\n", __func__, 593 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive", 594 ticks, duration); 595 596 scan_update_locked(vap, scan); 597 if (ss->ss_ops != NULL) { 598 ss->ss_vap = vap; 599 /* 600 * A background scan does not select a new sta; it 601 * just refreshes the scan cache. Also, indicate 602 * the scan logic should follow the beacon schedule: 603 * we go off-channel and scan for a while, then 604 * return to the bss channel to receive a beacon, 605 * then go off-channel again. All during this time 606 * we notify the ap we're in power save mode. When 607 * the scan is complete we leave power save mode. 608 * If any beacon indicates there are frames pending 609 * for us then we drop out of power save mode 610 * (and background scan) automatically by way of the 611 * usual sta power save logic. 612 */ 613 ss->ss_flags |= IEEE80211_SCAN_NOPICK 614 | IEEE80211_SCAN_BGSCAN 615 | flags 616 ; 617 /* if previous scan completed, restart */ 618 if (ss->ss_next >= ss->ss_last) { 619 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 620 vap->iv_stats.is_scan_active++; 621 else 622 vap->iv_stats.is_scan_passive++; 623 /* 624 * NB: beware of the scan cache being flushed; 625 * if the channel list is empty use the 626 * scan_start method to populate it. 627 */ 628 ss->ss_next = 0; 629 if (ss->ss_last != 0) 630 ss->ss_ops->scan_restart(ss, vap); 631 else { 632 ss->ss_ops->scan_start(ss, vap); 633 #ifdef IEEE80211_DEBUG 634 if (ieee80211_msg_scan(vap)) 635 scan_dump(ss); 636 #endif /* IEEE80211_DEBUG */ 637 } 638 } 639 /* NB: flush frames rx'd before 1st channel change */ 640 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_DISCARD; 641 SCAN_PRIVATE(ss)->ss_duration = duration; 642 ss->ss_maxdwell = duration; 643 ic->ic_flags |= IEEE80211_F_SCAN; 644 ic->ic_flags_ext |= IEEE80211_FEXT_BGSCAN; 645 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task); 646 } else { 647 /* XXX msg+stat */ 648 } 649 } else { 650 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 651 "%s: %s scan already in progress\n", __func__, 652 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"); 653 } 654 655 /* NB: racey, does it matter? */ 656 return (ic->ic_flags & IEEE80211_F_SCAN); 657 } 658 659 /* 660 * Cancel any scan currently going on for the specified vap. 661 */ 662 void 663 ieee80211_cancel_scan(struct ieee80211vap *vap) 664 { 665 struct ieee80211com *ic = vap->iv_ic; 666 struct ieee80211_scan_state *ss = ic->ic_scan; 667 668 if ((ic->ic_flags & IEEE80211_F_SCAN) && 669 ss->ss_vap == vap && 670 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) { 671 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 672 "%s: cancel %s scan\n", __func__, 673 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? 674 "active" : "passive"); 675 676 /* clear bg scan NOPICK and mark cancel request */ 677 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 678 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL; 679 /* wake up the scan task */ 680 scan_signal(ss); 681 } 682 } 683 684 /* 685 * Cancel any scan currently going on. 686 */ 687 void 688 ieee80211_cancel_anyscan(struct ieee80211vap *vap) 689 { 690 struct ieee80211com *ic = vap->iv_ic; 691 struct ieee80211_scan_state *ss = ic->ic_scan; 692 693 if ((ic->ic_flags & IEEE80211_F_SCAN) && 694 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0) { 695 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 696 "%s: cancel %s scan\n", __func__, 697 ss->ss_flags & IEEE80211_SCAN_ACTIVE ? 698 "active" : "passive"); 699 700 /* clear bg scan NOPICK and mark cancel request */ 701 ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; 702 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_CANCEL; 703 /* wake up the scan task */ 704 scan_signal(ss); 705 } 706 } 707 708 /* 709 * Public access to scan_next for drivers that manage 710 * scanning themselves (e.g. for firmware-based devices). 711 */ 712 void 713 ieee80211_scan_next(struct ieee80211vap *vap) 714 { 715 struct ieee80211com *ic = vap->iv_ic; 716 struct ieee80211_scan_state *ss = ic->ic_scan; 717 718 /* wake up the scan task */ 719 scan_signal(ss); 720 } 721 722 /* 723 * Public access to scan_next for drivers that are not able to scan single 724 * channels (e.g. for firmware-based devices). 725 */ 726 void 727 ieee80211_scan_done(struct ieee80211vap *vap) 728 { 729 struct ieee80211com *ic = vap->iv_ic; 730 struct ieee80211_scan_state *ss; 731 732 ss = ic->ic_scan; 733 ss->ss_next = ss->ss_last; /* all channels are complete */ 734 scan_signal(ss); 735 } 736 737 /* 738 * Probe the curent channel, if allowed, while scanning. 739 * If the channel is not marked passive-only then send 740 * a probe request immediately. Otherwise mark state and 741 * listen for beacons on the channel; if we receive something 742 * then we'll transmit a probe request. 743 */ 744 void 745 ieee80211_probe_curchan(struct ieee80211vap *vap, int force) 746 { 747 struct ieee80211com *ic = vap->iv_ic; 748 struct ieee80211_scan_state *ss = ic->ic_scan; 749 struct ifnet *ifp = vap->iv_ifp; 750 int i; 751 752 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) { 753 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN; 754 return; 755 } 756 /* 757 * Send directed probe requests followed by any 758 * broadcast probe request. 759 * XXX remove dependence on ic/vap->iv_bss 760 */ 761 for (i = 0; i < ss->ss_nssid; i++) 762 ieee80211_send_probereq(vap->iv_bss, 763 vap->iv_myaddr, ifp->if_broadcastaddr, 764 ifp->if_broadcastaddr, 765 ss->ss_ssid[i].ssid, ss->ss_ssid[i].len); 766 if ((ss->ss_flags & IEEE80211_SCAN_NOBCAST) == 0) 767 ieee80211_send_probereq(vap->iv_bss, 768 vap->iv_myaddr, ifp->if_broadcastaddr, 769 ifp->if_broadcastaddr, 770 "", 0); 771 } 772 773 /* 774 * Scan curchan. If this is an active scan and the channel 775 * is not marked passive then send probe request frame(s). 776 * Arrange for the channel change after maxdwell ticks. 777 */ 778 static void 779 scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell) 780 { 781 struct ieee80211vap *vap = ss->ss_vap; 782 783 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 784 ieee80211_probe_curchan(vap, 0); 785 callout_reset(&SCAN_PRIVATE(ss)->ss_scan_timer, 786 maxdwell, scan_signal_callout, ss); 787 } 788 789 static void 790 scan_signal_callout(void *arg) 791 { 792 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg; 793 794 wlan_serialize_enter(); 795 scan_signal(ss); 796 wlan_serialize_exit(); 797 } 798 799 static void 800 scan_signal(struct ieee80211_scan_state *ss) 801 { 802 wlan_cv_signal(&SCAN_PRIVATE(ss)->ss_scan_cv, 0); 803 } 804 805 /* 806 * Handle mindwell requirements completed; initiate a channel 807 * change to the next channel asap. 808 */ 809 static void 810 scan_mindwell(struct ieee80211_scan_state *ss) 811 { 812 scan_signal(ss); 813 } 814 815 static void 816 scan_task(void *arg, int pending) 817 { 818 #define ISCAN_REP (ISCAN_MINDWELL | ISCAN_DISCARD) 819 struct ieee80211_scan_state *ss = (struct ieee80211_scan_state *) arg; 820 struct ieee80211vap *vap; 821 struct ieee80211com *ic; 822 struct ieee80211_channel *chan; 823 unsigned long maxdwell, scanend; 824 int scandone = 0; 825 826 wlan_serialize_enter(); 827 vap = ss->ss_vap; 828 ic = ss->ss_ic; 829 830 if (vap == NULL || (ic->ic_flags & IEEE80211_F_SCAN) == 0 || 831 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT)) { 832 /* Cancelled before we started */ 833 goto done; 834 } 835 836 if (ss->ss_next == ss->ss_last) { 837 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 838 "%s: no channels to scan\n", __func__); 839 goto done; 840 } 841 842 if (vap->iv_opmode == IEEE80211_M_STA && 843 vap->iv_state == IEEE80211_S_RUN) { 844 if ((vap->iv_bss->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) { 845 /* Enable station power save mode */ 846 ieee80211_sta_pwrsave(vap, 1); 847 /* 848 * Use an 1ms delay so the null data frame has a chance 849 * to go out. Minimum one tick. 850 * XXX Should use M_TXCB mechanism to eliminate this. 851 */ 852 wlan_cv_timedwait(&SCAN_PRIVATE(ss)->ss_scan_cv, 853 hz / 1000 + 1); 854 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) 855 goto done; 856 } 857 } 858 859 scanend = ticks + SCAN_PRIVATE(ss)->ss_duration; 860 ic->ic_scan_start(ic); /* notify driver */ 861 862 for (;;) { 863 scandone = (ss->ss_next >= ss->ss_last) || 864 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) != 0; 865 if (scandone || (ss->ss_flags & IEEE80211_SCAN_GOTPICK) || 866 (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) || 867 time_after(ticks + ss->ss_mindwell, scanend)) 868 break; 869 870 chan = ss->ss_chans[ss->ss_next++]; 871 872 /* 873 * Watch for truncation due to the scan end time. 874 */ 875 if (time_after(ticks + ss->ss_maxdwell, scanend)) 876 maxdwell = scanend - ticks; 877 else 878 maxdwell = ss->ss_maxdwell; 879 880 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 881 "%s: chan %3d%c -> %3d%c [%s, dwell min %lums max %lums]\n", 882 __func__, 883 ieee80211_chan2ieee(ic, ic->ic_curchan), 884 channel_type(ic->ic_curchan), 885 ieee80211_chan2ieee(ic, chan), channel_type(chan), 886 (ss->ss_flags & IEEE80211_SCAN_ACTIVE) && 887 (chan->ic_flags & IEEE80211_CHAN_PASSIVE) == 0 ? 888 "active" : "passive", 889 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(maxdwell)); 890 891 /* 892 * Potentially change channel and phy mode. 893 */ 894 ic->ic_curchan = chan; 895 ic->ic_rt = ieee80211_get_ratetable(chan); 896 /* 897 * Perform the channel change and scan unlocked so the driver 898 * may sleep. Once set_channel returns the hardware has 899 * completed the channel change. 900 */ 901 ic->ic_set_channel(ic); 902 ieee80211_radiotap_chan_change(ic); 903 904 /* 905 * Scan curchan. Drivers for "intelligent hardware" 906 * override ic_scan_curchan to tell the device to do 907 * the work. Otherwise we manage the work outselves; 908 * sending a probe request (as needed), and arming the 909 * timeout to switch channels after maxdwell ticks. 910 * 911 * scan_curchan should only pause for the time required to 912 * prepare/initiate the hardware for the scan (if at all), the 913 * below condvar is used to sleep for the channels dwell time 914 * and allows it to be signalled for abort. 915 */ 916 ic->ic_scan_curchan(ss, maxdwell); 917 918 SCAN_PRIVATE(ss)->ss_chanmindwell = ticks + ss->ss_mindwell; 919 /* clear mindwell lock and initial channel change flush */ 920 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP; 921 922 if ((SCAN_PRIVATE(ss)->ss_iflags & (ISCAN_CANCEL|ISCAN_ABORT))) 923 continue; 924 925 /* Wait to be signalled to scan the next channel */ 926 wlan_cv_wait(&SCAN_PRIVATE(ss)->ss_scan_cv); 927 } 928 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_ABORT) 929 goto done; 930 931 ic->ic_scan_end(ic); /* notify driver */ 932 933 /* 934 * Record scan complete time. Note that we also do 935 * this when canceled so any background scan will 936 * not be restarted for a while. 937 */ 938 if (scandone) 939 ic->ic_lastscan = ticks; 940 /* return to the bss channel */ 941 if (ic->ic_bsschan != IEEE80211_CHAN_ANYC && 942 ic->ic_curchan != ic->ic_bsschan) { 943 ieee80211_setupcurchan(ic, ic->ic_bsschan); 944 ic->ic_set_channel(ic); 945 ieee80211_radiotap_chan_change(ic); 946 } 947 /* clear internal flags and any indication of a pick */ 948 SCAN_PRIVATE(ss)->ss_iflags &= ~ISCAN_REP; 949 ss->ss_flags &= ~IEEE80211_SCAN_GOTPICK; 950 951 /* 952 * If not canceled and scan completed, do post-processing. 953 * If the callback function returns 0, then it wants to 954 * continue/restart scanning. Unfortunately we needed to 955 * notify the driver to end the scan above to avoid having 956 * rx frames alter the scan candidate list. 957 */ 958 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_CANCEL) == 0 && 959 !ss->ss_ops->scan_end(ss, vap) && 960 (ss->ss_flags & IEEE80211_SCAN_ONCE) == 0 && 961 time_before(ticks + ss->ss_mindwell, scanend)) { 962 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 963 "%s: done, restart " 964 "[ticks %u, dwell min %lu scanend %lu]\n", 965 __func__, 966 ticks, ss->ss_mindwell, scanend); 967 ss->ss_next = 0; /* reset to begining */ 968 if (ss->ss_flags & IEEE80211_SCAN_ACTIVE) 969 vap->iv_stats.is_scan_active++; 970 else 971 vap->iv_stats.is_scan_passive++; 972 973 ss->ss_ops->scan_restart(ss, vap); /* XXX? */ 974 ieee80211_runtask(ic, &SCAN_PRIVATE(ss)->ss_scan_task); 975 goto done2; 976 } 977 978 /* past here, scandone is ``true'' if not in bg mode */ 979 if ((ss->ss_flags & IEEE80211_SCAN_BGSCAN) == 0) 980 scandone = 1; 981 982 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 983 "%s: %s, [ticks %u, dwell min %lu scanend %lu]\n", 984 __func__, scandone ? "done" : "stopped", 985 ticks, ss->ss_mindwell, scanend); 986 987 /* 988 * Clear the SCAN bit first in case frames are 989 * pending on the station power save queue. If 990 * we defer this then the dispatch of the frames 991 * may generate a request to cancel scanning. 992 */ 993 done: 994 ic->ic_flags &= ~IEEE80211_F_SCAN; 995 /* 996 * Drop out of power save mode when a scan has 997 * completed. If this scan was prematurely terminated 998 * because it is a background scan then don't notify 999 * the ap; we'll either return to scanning after we 1000 * receive the beacon frame or we'll drop out of power 1001 * save mode because the beacon indicates we have frames 1002 * waiting for us. 1003 */ 1004 if (scandone) { 1005 ieee80211_sta_pwrsave(vap, 0); 1006 if (ss->ss_next >= ss->ss_last) { 1007 ieee80211_notify_scan_done(vap); 1008 ic->ic_flags_ext &= ~IEEE80211_FEXT_BGSCAN; 1009 } 1010 } 1011 SCAN_PRIVATE(ss)->ss_iflags &= ~(ISCAN_CANCEL|ISCAN_ABORT); 1012 ss->ss_flags &= ~(IEEE80211_SCAN_ONCE | IEEE80211_SCAN_PICK1ST); 1013 done2: 1014 wlan_serialize_exit(); 1015 #undef ISCAN_REP 1016 } 1017 1018 #ifdef IEEE80211_DEBUG 1019 static void 1020 dump_country(const uint8_t *ie) 1021 { 1022 const struct ieee80211_country_ie *cie = 1023 (const struct ieee80211_country_ie *) ie; 1024 int i, nbands, schan, nchan; 1025 1026 if (cie->len < 3) { 1027 kprintf(" <bogus country ie, len %d>", cie->len); 1028 return; 1029 } 1030 kprintf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]); 1031 nbands = (cie->len - 3) / sizeof(cie->band[0]); 1032 for (i = 0; i < nbands; i++) { 1033 schan = cie->band[i].schan; 1034 nchan = cie->band[i].nchan; 1035 if (nchan != 1) 1036 kprintf(" %u-%u,%u", schan, schan + nchan-1, 1037 cie->band[i].maxtxpwr); 1038 else 1039 kprintf(" %u,%u", schan, cie->band[i].maxtxpwr); 1040 } 1041 kprintf("]"); 1042 } 1043 1044 static void 1045 dump_probe_beacon(uint8_t subtype, int isnew, 1046 const uint8_t mac[IEEE80211_ADDR_LEN], 1047 const struct ieee80211_scanparams *sp, int rssi) 1048 { 1049 char ethstr[ETHER_ADDRSTRLEN + 1]; 1050 1051 kprintf("[%s] %s%s on chan %u (bss chan %u) ", 1052 kether_ntoa(mac, ethstr), isnew ? "new " : "", 1053 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT], 1054 sp->chan, sp->bchan); 1055 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]); 1056 kprintf(" rssi %d\n", rssi); 1057 1058 if (isnew) { 1059 kprintf("[%s] caps 0x%x bintval %u erp 0x%x", 1060 kether_ntoa(mac, ethstr), sp->capinfo, sp->bintval, sp->erp); 1061 if (sp->country != NULL) 1062 dump_country(sp->country); 1063 kprintf("\n"); 1064 } 1065 } 1066 #endif /* IEEE80211_DEBUG */ 1067 1068 /* 1069 * Process a beacon or probe response frame. 1070 */ 1071 void 1072 ieee80211_add_scan(struct ieee80211vap *vap, 1073 const struct ieee80211_scanparams *sp, 1074 const struct ieee80211_frame *wh, 1075 int subtype, int rssi, int noise) 1076 { 1077 struct ieee80211com *ic = vap->iv_ic; 1078 struct ieee80211_scan_state *ss = ic->ic_scan; 1079 1080 /* XXX locking */ 1081 /* 1082 * Frames received during startup are discarded to avoid 1083 * using scan state setup on the initial entry to the timer 1084 * callback. This can occur because the device may enable 1085 * rx prior to our doing the initial channel change in the 1086 * timer routine. 1087 */ 1088 if (SCAN_PRIVATE(ss)->ss_iflags & ISCAN_DISCARD) 1089 return; 1090 #ifdef IEEE80211_DEBUG 1091 if (ieee80211_msg_scan(vap) && (ic->ic_flags & IEEE80211_F_SCAN)) 1092 dump_probe_beacon(subtype, 1, wh->i_addr2, sp, rssi); 1093 #endif 1094 if (ss->ss_ops != NULL && 1095 ss->ss_ops->scan_add(ss, sp, wh, subtype, rssi, noise)) { 1096 /* 1097 * If we've reached the min dwell time terminate 1098 * the timer so we'll switch to the next channel. 1099 */ 1100 if ((SCAN_PRIVATE(ss)->ss_iflags & ISCAN_MINDWELL) == 0 && 1101 time_after_eq(ticks, SCAN_PRIVATE(ss)->ss_chanmindwell)) { 1102 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 1103 "%s: chan %3d%c min dwell met (%u > %lu)\n", 1104 __func__, 1105 ieee80211_chan2ieee(ic, ic->ic_curchan), 1106 channel_type(ic->ic_curchan), 1107 ticks, SCAN_PRIVATE(ss)->ss_chanmindwell); 1108 SCAN_PRIVATE(ss)->ss_iflags |= ISCAN_MINDWELL; 1109 /* 1110 * NB: trigger at next clock tick or wait for the 1111 * hardware. 1112 */ 1113 ic->ic_scan_mindwell(ss); 1114 } 1115 } 1116 } 1117 1118 /* 1119 * Timeout/age scan cache entries; called from sta timeout 1120 * timer (XXX should be self-contained). 1121 */ 1122 void 1123 ieee80211_scan_timeout(struct ieee80211com *ic) 1124 { 1125 struct ieee80211_scan_state *ss = ic->ic_scan; 1126 1127 if (ss->ss_ops != NULL) 1128 ss->ss_ops->scan_age(ss); 1129 } 1130 1131 /* 1132 * Mark a scan cache entry after a successful associate. 1133 */ 1134 void 1135 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[]) 1136 { 1137 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1138 1139 if (ss->ss_ops != NULL) { 1140 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, 1141 mac, "%s", __func__); 1142 ss->ss_ops->scan_assoc_success(ss, mac); 1143 } 1144 } 1145 1146 /* 1147 * Demerit a scan cache entry after failing to associate. 1148 */ 1149 void 1150 ieee80211_scan_assoc_fail(struct ieee80211vap *vap, 1151 const uint8_t mac[], int reason) 1152 { 1153 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1154 1155 if (ss->ss_ops != NULL) { 1156 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac, 1157 "%s: reason %u", __func__, reason); 1158 ss->ss_ops->scan_assoc_fail(ss, mac, reason); 1159 } 1160 } 1161 1162 /* 1163 * Iterate over the contents of the scan cache. 1164 */ 1165 void 1166 ieee80211_scan_iterate(struct ieee80211vap *vap, 1167 ieee80211_scan_iter_func *f, void *arg) 1168 { 1169 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1170 1171 if (ss->ss_ops != NULL) 1172 ss->ss_ops->scan_iterate(ss, f, arg); 1173 } 1174 1175 /* 1176 * Flush the contents of the scan cache. 1177 */ 1178 void 1179 ieee80211_scan_flush(struct ieee80211vap *vap) 1180 { 1181 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 1182 1183 if (ss->ss_ops != NULL && ss->ss_vap == vap) { 1184 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__); 1185 ss->ss_ops->scan_flush(ss); 1186 } 1187 } 1188 1189 /* 1190 * Check the scan cache for an ap/channel to use; if that 1191 * fails then kick off a new scan. 1192 */ 1193 struct ieee80211_channel * 1194 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags) 1195 { 1196 struct ieee80211_scan_state *ss = ic->ic_scan; 1197 1198 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) { 1199 /* XXX printf? */ 1200 return NULL; 1201 } 1202 if (ss->ss_ops->scan_pickchan == NULL) { 1203 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN, 1204 "%s: scan module does not support picking a channel, " 1205 "opmode %d\n", __func__, ss->ss_vap->iv_opmode); 1206 return NULL; 1207 } 1208 return ss->ss_ops->scan_pickchan(ss, flags); 1209 } 1210