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("$FreeBSD$"); 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/proc.h> 37 #include <sys/kernel.h> 38 #include <sys/malloc.h> 39 #include <sys/condvar.h> 40 41 #include <sys/socket.h> 42 43 #include <net/if.h> 44 #include <net/if_var.h> 45 #include <net/if_media.h> 46 #include <net/ethernet.h> 47 48 #include <net80211/ieee80211_var.h> 49 50 /* XXX until it's implemented as attach ops */ 51 #include <net80211/ieee80211_scan_sw.h> 52 53 #include <net/bpf.h> 54 55 /* 56 * Roaming-related defaults. RSSI thresholds are as returned by the 57 * driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e 58 * .5M units) or MCS. 59 */ 60 /* rssi thresholds */ 61 #define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */ 62 #define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */ 63 #define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */ 64 /* transmit rate thresholds */ 65 #define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */ 66 #define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */ 67 #define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */ 68 #define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */ 69 #define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */ 70 #define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */ 71 72 void 73 ieee80211_scan_attach(struct ieee80211com *ic) 74 { 75 /* 76 * If there's no scan method pointer, attach the 77 * swscan set as a default. 78 */ 79 if (ic->ic_scan_methods == NULL) 80 ieee80211_swscan_attach(ic); 81 else 82 ic->ic_scan_methods->sc_attach(ic); 83 } 84 85 void 86 ieee80211_scan_detach(struct ieee80211com *ic) 87 { 88 89 /* 90 * Ideally we'd do the ss_ops detach call here; 91 * but then sc_detach() would need to be split in two. 92 * 93 * I'll do that later. 94 */ 95 ic->ic_scan_methods->sc_detach(ic); 96 } 97 98 static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = { 99 [IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT, 100 .rate = ROAM_RATE_11A_DEFAULT }, 101 [IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT, 102 .rate = ROAM_RATE_11B_DEFAULT }, 103 [IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT, 104 .rate = ROAM_RATE_11BONLY_DEFAULT }, 105 [IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT, 106 .rate = ROAM_RATE_11A_DEFAULT }, 107 [IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT, 108 .rate = ROAM_RATE_11A_DEFAULT }, 109 [IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT, 110 .rate = ROAM_RATE_11A_DEFAULT }, 111 [IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT, 112 .rate = ROAM_RATE_HALF_DEFAULT }, 113 [IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT, 114 .rate = ROAM_RATE_QUARTER_DEFAULT }, 115 [IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT, 116 .rate = ROAM_MCS_11N_DEFAULT }, 117 [IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT, 118 .rate = ROAM_MCS_11N_DEFAULT }, 119 }; 120 121 void 122 ieee80211_scan_vattach(struct ieee80211vap *vap) 123 { 124 struct ieee80211com *ic = vap->iv_ic; 125 126 vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz; 127 vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz; 128 vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz; 129 130 vap->iv_roaming = IEEE80211_ROAMING_AUTO; 131 memcpy(vap->iv_roamparms, defroam, sizeof(defroam)); 132 133 ic->ic_scan_methods->sc_vattach(vap); 134 } 135 136 void 137 ieee80211_scan_vdetach(struct ieee80211vap *vap) 138 { 139 struct ieee80211com *ic = vap->iv_ic; 140 struct ieee80211_scan_state *ss; 141 142 IEEE80211_LOCK(ic); 143 ss = ic->ic_scan; 144 145 ic->ic_scan_methods->sc_vdetach(vap); 146 147 if (ss != NULL && ss->ss_vap == vap) { 148 if (ss->ss_ops != NULL) { 149 ss->ss_ops->scan_detach(ss); 150 ss->ss_ops = NULL; 151 } 152 ss->ss_vap = NULL; 153 } 154 IEEE80211_UNLOCK(ic); 155 } 156 157 /* 158 * Simple-minded scanner module support. 159 */ 160 static const char *scan_modnames[IEEE80211_OPMODE_MAX] = { 161 "wlan_scan_sta", /* IEEE80211_M_IBSS */ 162 "wlan_scan_sta", /* IEEE80211_M_STA */ 163 "wlan_scan_wds", /* IEEE80211_M_WDS */ 164 "wlan_scan_sta", /* IEEE80211_M_AHDEMO */ 165 "wlan_scan_ap", /* IEEE80211_M_HOSTAP */ 166 "wlan_scan_monitor", /* IEEE80211_M_MONITOR */ 167 "wlan_scan_sta", /* IEEE80211_M_MBSS */ 168 }; 169 static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX]; 170 171 const struct ieee80211_scanner * 172 ieee80211_scanner_get(enum ieee80211_opmode mode) 173 { 174 if (mode >= IEEE80211_OPMODE_MAX) 175 return NULL; 176 if (scanners[mode] == NULL) 177 ieee80211_load_module(scan_modnames[mode]); 178 return scanners[mode]; 179 } 180 181 void 182 ieee80211_scanner_register(enum ieee80211_opmode mode, 183 const struct ieee80211_scanner *scan) 184 { 185 if (mode >= IEEE80211_OPMODE_MAX) 186 return; 187 scanners[mode] = scan; 188 } 189 190 void 191 ieee80211_scanner_unregister(enum ieee80211_opmode mode, 192 const struct ieee80211_scanner *scan) 193 { 194 if (mode >= IEEE80211_OPMODE_MAX) 195 return; 196 if (scanners[mode] == scan) 197 scanners[mode] = NULL; 198 } 199 200 void 201 ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan) 202 { 203 int m; 204 205 for (m = 0; m < IEEE80211_OPMODE_MAX; m++) 206 if (scanners[m] == scan) 207 scanners[m] = NULL; 208 } 209 210 /* 211 * Update common scanner state to reflect the current 212 * operating mode. This is called when the state machine 213 * is transitioned to RUN state w/o scanning--e.g. when 214 * operating in monitor mode. The purpose of this is to 215 * ensure later callbacks find ss_ops set to properly 216 * reflect current operating mode. 217 */ 218 void 219 ieee80211_scan_update_locked(struct ieee80211vap *vap, 220 const struct ieee80211_scanner *scan) 221 { 222 struct ieee80211com *ic = vap->iv_ic; 223 struct ieee80211_scan_state *ss = ic->ic_scan; 224 225 IEEE80211_LOCK_ASSERT(ic); 226 227 #ifdef IEEE80211_DEBUG 228 if (ss->ss_vap != vap || ss->ss_ops != scan) { 229 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 230 "%s: current scanner is <%s:%s>, switch to <%s:%s>\n", 231 __func__, 232 ss->ss_vap != NULL ? 233 ss->ss_vap->iv_ifp->if_xname : "none", 234 ss->ss_vap != NULL ? 235 ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none", 236 vap->iv_ifp->if_xname, 237 ieee80211_opmode_name[vap->iv_opmode]); 238 } 239 #endif 240 ss->ss_vap = vap; 241 if (ss->ss_ops != scan) { 242 /* 243 * Switch scanners; detach old, attach new. Special 244 * case where a single scan module implements multiple 245 * policies by using different scan ops but a common 246 * core. We assume if the old and new attach methods 247 * are identical then it's ok to just change ss_ops 248 * and not flush the internal state of the module. 249 */ 250 if (scan == NULL || ss->ss_ops == NULL || 251 ss->ss_ops->scan_attach != scan->scan_attach) { 252 if (ss->ss_ops != NULL) 253 ss->ss_ops->scan_detach(ss); 254 if (scan != NULL && !scan->scan_attach(ss)) { 255 /* XXX attach failure */ 256 /* XXX stat+msg */ 257 scan = NULL; 258 } 259 } 260 ss->ss_ops = scan; 261 } 262 } 263 264 void 265 ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss) 266 { 267 struct ieee80211com *ic = ss->ss_ic; 268 const char *sep; 269 int i; 270 271 sep = ""; 272 for (i = ss->ss_next; i < ss->ss_last; i++) { 273 const struct ieee80211_channel *c = ss->ss_chans[i]; 274 275 printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c), 276 ieee80211_channel_type_char(c)); 277 sep = ", "; 278 } 279 } 280 281 #ifdef IEEE80211_DEBUG 282 void 283 ieee80211_scan_dump(struct ieee80211_scan_state *ss) 284 { 285 struct ieee80211vap *vap = ss->ss_vap; 286 287 if_printf(vap->iv_ifp, "scan set "); 288 ieee80211_scan_dump_channels(ss); 289 printf(" dwell min %lums max %lums\n", 290 ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell)); 291 } 292 #endif /* IEEE80211_DEBUG */ 293 294 void 295 ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss, 296 int nssid, const struct ieee80211_scan_ssid ssids[]) 297 { 298 if (nssid > IEEE80211_SCAN_MAX_SSID) { 299 /* XXX printf */ 300 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 301 "%s: too many ssid %d, ignoring all of them\n", 302 __func__, nssid); 303 return; 304 } 305 memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0])); 306 ss->ss_nssid = nssid; 307 } 308 309 /* 310 * Start a scan unless one is already going. 311 */ 312 int 313 ieee80211_start_scan(struct ieee80211vap *vap, int flags, 314 u_int duration, u_int mindwell, u_int maxdwell, 315 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 316 { 317 const struct ieee80211_scanner *scan; 318 struct ieee80211com *ic = vap->iv_ic; 319 320 scan = ieee80211_scanner_get(vap->iv_opmode); 321 if (scan == NULL) { 322 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 323 "%s: no scanner support for %s mode\n", 324 __func__, ieee80211_opmode_name[vap->iv_opmode]); 325 /* XXX stat */ 326 return 0; 327 } 328 329 return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration, 330 mindwell, maxdwell, nssid, ssids); 331 } 332 333 /* 334 * Check the scan cache for an ap/channel to use; if that 335 * fails then kick off a new scan. 336 */ 337 int 338 ieee80211_check_scan(struct ieee80211vap *vap, int flags, 339 u_int duration, u_int mindwell, u_int maxdwell, 340 u_int nssid, const struct ieee80211_scan_ssid ssids[]) 341 { 342 struct ieee80211com *ic = vap->iv_ic; 343 struct ieee80211_scan_state *ss = ic->ic_scan; 344 const struct ieee80211_scanner *scan; 345 int result; 346 347 scan = ieee80211_scanner_get(vap->iv_opmode); 348 if (scan == NULL) { 349 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 350 "%s: no scanner support for %s mode\n", 351 __func__, vap->iv_opmode); 352 /* XXX stat */ 353 return 0; 354 } 355 356 /* 357 * Check if there's a list of scan candidates already. 358 * XXX want more than the ap we're currently associated with 359 */ 360 361 IEEE80211_LOCK(ic); 362 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 363 "%s: %s scan, %s%s%s%s%s\n" 364 , __func__ 365 , flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive" 366 , flags & IEEE80211_SCAN_FLUSH ? "flush" : "append" 367 , flags & IEEE80211_SCAN_NOPICK ? ", nopick" : "" 368 , flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : "" 369 , flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : "" 370 , flags & IEEE80211_SCAN_ONCE ? ", once" : "" 371 ); 372 373 if (ss->ss_ops != scan) { 374 /* XXX re-use cache contents? e.g. adhoc<->sta */ 375 flags |= IEEE80211_SCAN_FLUSH; 376 } 377 378 /* 379 * XXX TODO: separate things out a bit better. 380 */ 381 ieee80211_scan_update_locked(vap, scan); 382 383 result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration, 384 mindwell, maxdwell, nssid, ssids); 385 386 IEEE80211_UNLOCK(ic); 387 388 return (result); 389 } 390 391 /* 392 * Check the scan cache for an ap/channel to use; if that fails 393 * then kick off a scan using the current settings. 394 */ 395 int 396 ieee80211_check_scan_current(struct ieee80211vap *vap) 397 { 398 return ieee80211_check_scan(vap, 399 IEEE80211_SCAN_ACTIVE, 400 IEEE80211_SCAN_FOREVER, 0, 0, 401 vap->iv_des_nssid, vap->iv_des_ssid); 402 } 403 404 /* 405 * Restart a previous scan. If the previous scan completed 406 * then we start again using the existing channel list. 407 */ 408 int 409 ieee80211_bg_scan(struct ieee80211vap *vap, int flags) 410 { 411 struct ieee80211com *ic = vap->iv_ic; 412 const struct ieee80211_scanner *scan; 413 414 // IEEE80211_UNLOCK_ASSERT(sc); 415 416 scan = ieee80211_scanner_get(vap->iv_opmode); 417 if (scan == NULL) { 418 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, 419 "%s: no scanner support for %s mode\n", 420 __func__, vap->iv_opmode); 421 /* XXX stat */ 422 return 0; 423 } 424 425 /* 426 * XXX TODO: pull apart the bgscan logic into whatever 427 * belongs here and whatever belongs in the software 428 * scanner. 429 */ 430 return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags)); 431 } 432 433 /* 434 * Cancel any scan currently going on for the specified vap. 435 */ 436 void 437 ieee80211_cancel_scan(struct ieee80211vap *vap) 438 { 439 struct ieee80211com *ic = vap->iv_ic; 440 441 ic->ic_scan_methods->sc_cancel_scan(vap); 442 } 443 444 /* 445 * Cancel any scan currently going on. 446 */ 447 void 448 ieee80211_cancel_anyscan(struct ieee80211vap *vap) 449 { 450 struct ieee80211com *ic = vap->iv_ic; 451 452 ic->ic_scan_methods->sc_cancel_anyscan(vap); 453 } 454 455 /* 456 * Public access to scan_next for drivers that manage 457 * scanning themselves (e.g. for firmware-based devices). 458 */ 459 void 460 ieee80211_scan_next(struct ieee80211vap *vap) 461 { 462 struct ieee80211com *ic = vap->iv_ic; 463 464 ic->ic_scan_methods->sc_scan_next(vap); 465 } 466 467 /* 468 * Public access to scan_next for drivers that are not able to scan single 469 * channels (e.g. for firmware-based devices). 470 */ 471 void 472 ieee80211_scan_done(struct ieee80211vap *vap) 473 { 474 struct ieee80211com *ic = vap->iv_ic; 475 struct ieee80211_scan_state *ss; 476 477 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__); 478 479 IEEE80211_LOCK(ic); 480 ss = ic->ic_scan; 481 ss->ss_next = ss->ss_last; /* all channels are complete */ 482 483 ic->ic_scan_methods->sc_scan_done(vap); 484 485 IEEE80211_UNLOCK(ic); 486 } 487 488 /* 489 * Probe the curent channel, if allowed, while scanning. 490 * If the channel is not marked passive-only then send 491 * a probe request immediately. Otherwise mark state and 492 * listen for beacons on the channel; if we receive something 493 * then we'll transmit a probe request. 494 */ 495 void 496 ieee80211_probe_curchan(struct ieee80211vap *vap, int force) 497 { 498 struct ieee80211com *ic = vap->iv_ic; 499 500 if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) { 501 ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN; 502 return; 503 } 504 505 ic->ic_scan_methods->sc_scan_probe_curchan(vap, force); 506 } 507 508 #ifdef IEEE80211_DEBUG 509 static void 510 dump_country(const uint8_t *ie) 511 { 512 const struct ieee80211_country_ie *cie = 513 (const struct ieee80211_country_ie *) ie; 514 int i, nbands, schan, nchan; 515 516 if (cie->len < 3) { 517 printf(" <bogus country ie, len %d>", cie->len); 518 return; 519 } 520 printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]); 521 nbands = (cie->len - 3) / sizeof(cie->band[0]); 522 for (i = 0; i < nbands; i++) { 523 schan = cie->band[i].schan; 524 nchan = cie->band[i].nchan; 525 if (nchan != 1) 526 printf(" %u-%u,%u", schan, schan + nchan-1, 527 cie->band[i].maxtxpwr); 528 else 529 printf(" %u,%u", schan, cie->band[i].maxtxpwr); 530 } 531 printf("]"); 532 } 533 534 void 535 ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew, 536 const uint8_t mac[IEEE80211_ADDR_LEN], 537 const struct ieee80211_scanparams *sp, int rssi) 538 { 539 540 printf("[%s] %s%s on chan %u (bss chan %u) ", 541 ether_sprintf(mac), isnew ? "new " : "", 542 ieee80211_mgt_subtype_name[subtype >> IEEE80211_FC0_SUBTYPE_SHIFT], 543 sp->chan, sp->bchan); 544 ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]); 545 printf(" rssi %d\n", rssi); 546 547 if (isnew) { 548 printf("[%s] caps 0x%x bintval %u erp 0x%x", 549 ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp); 550 if (sp->country != NULL) 551 dump_country(sp->country); 552 printf("\n"); 553 } 554 } 555 #endif /* IEEE80211_DEBUG */ 556 557 /* 558 * Process a beacon or probe response frame. 559 */ 560 void 561 ieee80211_add_scan(struct ieee80211vap *vap, 562 struct ieee80211_channel *curchan, 563 const struct ieee80211_scanparams *sp, 564 const struct ieee80211_frame *wh, 565 int subtype, int rssi, int noise) 566 { 567 struct ieee80211com *ic = vap->iv_ic; 568 569 return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype, 570 rssi, noise)); 571 } 572 573 /* 574 * Timeout/age scan cache entries; called from sta timeout 575 * timer (XXX should be self-contained). 576 */ 577 void 578 ieee80211_scan_timeout(struct ieee80211com *ic) 579 { 580 struct ieee80211_scan_state *ss = ic->ic_scan; 581 582 if (ss->ss_ops != NULL) 583 ss->ss_ops->scan_age(ss); 584 } 585 586 /* 587 * Mark a scan cache entry after a successful associate. 588 */ 589 void 590 ieee80211_scan_assoc_success(struct ieee80211vap *vap, const uint8_t mac[]) 591 { 592 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 593 594 if (ss->ss_ops != NULL) { 595 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, 596 mac, "%s", __func__); 597 ss->ss_ops->scan_assoc_success(ss, mac); 598 } 599 } 600 601 /* 602 * Demerit a scan cache entry after failing to associate. 603 */ 604 void 605 ieee80211_scan_assoc_fail(struct ieee80211vap *vap, 606 const uint8_t mac[], int reason) 607 { 608 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 609 610 if (ss->ss_ops != NULL) { 611 IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac, 612 "%s: reason %u", __func__, reason); 613 ss->ss_ops->scan_assoc_fail(ss, mac, reason); 614 } 615 } 616 617 /* 618 * Iterate over the contents of the scan cache. 619 */ 620 void 621 ieee80211_scan_iterate(struct ieee80211vap *vap, 622 ieee80211_scan_iter_func *f, void *arg) 623 { 624 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 625 626 if (ss->ss_ops != NULL) 627 ss->ss_ops->scan_iterate(ss, f, arg); 628 } 629 630 /* 631 * Flush the contents of the scan cache. 632 */ 633 void 634 ieee80211_scan_flush(struct ieee80211vap *vap) 635 { 636 struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan; 637 638 if (ss->ss_ops != NULL && ss->ss_vap == vap) { 639 IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__); 640 ss->ss_ops->scan_flush(ss); 641 } 642 } 643 644 /* 645 * Check the scan cache for an ap/channel to use; if that 646 * fails then kick off a new scan. 647 */ 648 struct ieee80211_channel * 649 ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags) 650 { 651 struct ieee80211_scan_state *ss = ic->ic_scan; 652 653 IEEE80211_LOCK_ASSERT(ic); 654 655 if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) { 656 /* XXX printf? */ 657 return NULL; 658 } 659 if (ss->ss_ops->scan_pickchan == NULL) { 660 IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN, 661 "%s: scan module does not support picking a channel, " 662 "opmode %s\n", __func__, ss->ss_vap->iv_opmode); 663 return NULL; 664 } 665 return ss->ss_ops->scan_pickchan(ss, flags); 666 } 667