1b032f27cSSam Leffler /*- 2fe267a55SPedro F. Giffuni * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3fe267a55SPedro F. Giffuni * 4b032f27cSSam Leffler * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting 5b032f27cSSam Leffler * All rights reserved. 6b032f27cSSam Leffler * 7b032f27cSSam Leffler * Redistribution and use in source and binary forms, with or without 8b032f27cSSam Leffler * modification, are permitted provided that the following conditions 9b032f27cSSam Leffler * are met: 10b032f27cSSam Leffler * 1. Redistributions of source code must retain the above copyright 11b032f27cSSam Leffler * notice, this list of conditions and the following disclaimer. 12b032f27cSSam Leffler * 2. Redistributions in binary form must reproduce the above copyright 13b032f27cSSam Leffler * notice, this list of conditions and the following disclaimer in the 14b032f27cSSam Leffler * documentation and/or other materials provided with the distribution. 15b032f27cSSam Leffler * 16b032f27cSSam Leffler * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17b032f27cSSam Leffler * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18b032f27cSSam Leffler * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19b032f27cSSam Leffler * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20b032f27cSSam Leffler * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21b032f27cSSam Leffler * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22b032f27cSSam Leffler * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23b032f27cSSam Leffler * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24b032f27cSSam Leffler * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25b032f27cSSam Leffler * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26b032f27cSSam Leffler */ 27b032f27cSSam Leffler 28b032f27cSSam Leffler #include <sys/cdefs.h> 29b032f27cSSam Leffler #ifdef __FreeBSD__ 30b032f27cSSam Leffler __FBSDID("$FreeBSD$"); 31b032f27cSSam Leffler #endif 32b032f27cSSam Leffler 33b032f27cSSam Leffler /* 34b032f27cSSam Leffler * IEEE 802.11 DFS/Radar support. 35b032f27cSSam Leffler */ 36b032f27cSSam Leffler #include "opt_inet.h" 37b032f27cSSam Leffler #include "opt_wlan.h" 38b032f27cSSam Leffler 39b032f27cSSam Leffler #include <sys/param.h> 40b032f27cSSam Leffler #include <sys/systm.h> 41b032f27cSSam Leffler #include <sys/mbuf.h> 42b032f27cSSam Leffler #include <sys/malloc.h> 43b032f27cSSam Leffler #include <sys/kernel.h> 44b032f27cSSam Leffler 45b032f27cSSam Leffler #include <sys/socket.h> 46b032f27cSSam Leffler #include <sys/sockio.h> 47b032f27cSSam Leffler #include <sys/endian.h> 48b032f27cSSam Leffler #include <sys/errno.h> 49b032f27cSSam Leffler #include <sys/proc.h> 50b032f27cSSam Leffler #include <sys/sysctl.h> 51b032f27cSSam Leffler 52b032f27cSSam Leffler #include <net/if.h> 5376039bc8SGleb Smirnoff #include <net/if_var.h> 54b032f27cSSam Leffler #include <net/if_media.h> 55c3322cb9SGleb Smirnoff #include <net/ethernet.h> 56b032f27cSSam Leffler 57b032f27cSSam Leffler #include <net80211/ieee80211_var.h> 58b032f27cSSam Leffler 59d745c852SEd Schouten static MALLOC_DEFINE(M_80211_DFS, "80211dfs", "802.11 DFS state"); 60b032f27cSSam Leffler 61a77b10b3SSam Leffler static int ieee80211_nol_timeout = 30*60; /* 30 minutes */ 62a77b10b3SSam Leffler SYSCTL_INT(_net_wlan, OID_AUTO, nol_timeout, CTLFLAG_RW, 63a77b10b3SSam Leffler &ieee80211_nol_timeout, 0, "NOL timeout (secs)"); 64b032f27cSSam Leffler #define NOL_TIMEOUT msecs_to_ticks(ieee80211_nol_timeout*1000) 65a77b10b3SSam Leffler 66a77b10b3SSam Leffler static int ieee80211_cac_timeout = 60; /* 60 seconds */ 67a77b10b3SSam Leffler SYSCTL_INT(_net_wlan, OID_AUTO, cac_timeout, CTLFLAG_RW, 68a77b10b3SSam Leffler &ieee80211_cac_timeout, 0, "CAC timeout (secs)"); 69b032f27cSSam Leffler #define CAC_TIMEOUT msecs_to_ticks(ieee80211_cac_timeout*1000) 70b032f27cSSam Leffler 7162f8a13aSAdrian Chadd /* 7262f8a13aSAdrian Chadd DFS* In order to facilitate debugging, a couple of operating 7362f8a13aSAdrian Chadd * modes aside from the default are needed. 7462f8a13aSAdrian Chadd * 7562f8a13aSAdrian Chadd * 0 - default CAC/NOL behaviour - ie, start CAC, place 7662f8a13aSAdrian Chadd * channel on NOL list. 7762f8a13aSAdrian Chadd * 1 - send CAC, but don't change channel or add the channel 7862f8a13aSAdrian Chadd * to the NOL list. 7962f8a13aSAdrian Chadd * 2 - just match on radar, don't send CAC or place channel in 8062f8a13aSAdrian Chadd * the NOL list. 8162f8a13aSAdrian Chadd */ 8262f8a13aSAdrian Chadd static int ieee80211_dfs_debug = DFS_DBG_NONE; 8362f8a13aSAdrian Chadd 8462f8a13aSAdrian Chadd /* 8562f8a13aSAdrian Chadd * This option must not be included in the default kernel 8662f8a13aSAdrian Chadd * as it allows users to plainly disable CAC/NOL handling. 8762f8a13aSAdrian Chadd */ 8862f8a13aSAdrian Chadd #ifdef IEEE80211_DFS_DEBUG 8962f8a13aSAdrian Chadd SYSCTL_INT(_net_wlan, OID_AUTO, dfs_debug, CTLFLAG_RW, 9062f8a13aSAdrian Chadd &ieee80211_dfs_debug, 0, "DFS debug behaviour"); 9162f8a13aSAdrian Chadd #endif 9262f8a13aSAdrian Chadd 9332b0e64bSAdrian Chadd static int 9432b0e64bSAdrian Chadd null_set_quiet(struct ieee80211_node *ni, u_int8_t *quiet_elm) 9532b0e64bSAdrian Chadd { 9632b0e64bSAdrian Chadd return ENOSYS; 9732b0e64bSAdrian Chadd } 9832b0e64bSAdrian Chadd 99b032f27cSSam Leffler void 100b032f27cSSam Leffler ieee80211_dfs_attach(struct ieee80211com *ic) 101b032f27cSSam Leffler { 102b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 103b032f27cSSam Leffler 10492c4a81cSSam Leffler callout_init_mtx(&dfs->nol_timer, IEEE80211_LOCK_OBJ(ic), 0); 10592c4a81cSSam Leffler callout_init_mtx(&dfs->cac_timer, IEEE80211_LOCK_OBJ(ic), 0); 10632b0e64bSAdrian Chadd 10732b0e64bSAdrian Chadd ic->ic_set_quiet = null_set_quiet; 108b032f27cSSam Leffler } 109b032f27cSSam Leffler 110b032f27cSSam Leffler void 111b032f27cSSam Leffler ieee80211_dfs_detach(struct ieee80211com *ic) 112b032f27cSSam Leffler { 113b032f27cSSam Leffler /* NB: we assume no locking is needed */ 114b032f27cSSam Leffler ieee80211_dfs_reset(ic); 115b032f27cSSam Leffler } 116b032f27cSSam Leffler 117b032f27cSSam Leffler void 118b032f27cSSam Leffler ieee80211_dfs_reset(struct ieee80211com *ic) 119b032f27cSSam Leffler { 120b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 121b032f27cSSam Leffler int i; 122b032f27cSSam Leffler 123b032f27cSSam Leffler /* NB: we assume no locking is needed */ 124b032f27cSSam Leffler /* NB: cac_timer should be cleared by the state machine */ 125b032f27cSSam Leffler callout_drain(&dfs->nol_timer); 126b032f27cSSam Leffler for (i = 0; i < ic->ic_nchans; i++) 127b032f27cSSam Leffler ic->ic_channels[i].ic_state = 0; 128b032f27cSSam Leffler dfs->lastchan = NULL; 129b032f27cSSam Leffler } 130b032f27cSSam Leffler 131b032f27cSSam Leffler static void 132b032f27cSSam Leffler cac_timeout(void *arg) 133b032f27cSSam Leffler { 134b032f27cSSam Leffler struct ieee80211vap *vap = arg; 135b032f27cSSam Leffler struct ieee80211com *ic = vap->iv_ic; 136b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 137b032f27cSSam Leffler int i; 138b032f27cSSam Leffler 13992c4a81cSSam Leffler IEEE80211_LOCK_ASSERT(ic); 14092c4a81cSSam Leffler 141b032f27cSSam Leffler if (vap->iv_state != IEEE80211_S_CAC) /* NB: just in case */ 142b032f27cSSam Leffler return; 143b032f27cSSam Leffler /* 144b032f27cSSam Leffler * When radar is detected during a CAC we are woken 145b032f27cSSam Leffler * up prematurely to switch to a new channel. 146b032f27cSSam Leffler * Check the channel to decide how to act. 147b032f27cSSam Leffler */ 148b032f27cSSam Leffler if (IEEE80211_IS_CHAN_RADAR(ic->ic_curchan)) { 149b032f27cSSam Leffler ieee80211_notify_cac(ic, ic->ic_curchan, 150b032f27cSSam Leffler IEEE80211_NOTIFY_CAC_RADAR); 151b032f27cSSam Leffler 152b032f27cSSam Leffler if_printf(vap->iv_ifp, 153b032f27cSSam Leffler "CAC timer on channel %u (%u MHz) stopped due to radar\n", 154b032f27cSSam Leffler ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq); 155b032f27cSSam Leffler 156b032f27cSSam Leffler /* XXX clobbers any existing desired channel */ 157b032f27cSSam Leffler /* NB: dfs->newchan may be NULL, that's ok */ 158b032f27cSSam Leffler vap->iv_des_chan = dfs->newchan; 1594ab4d681SAndriy Voskoboinyk ieee80211_new_state_locked(vap, IEEE80211_S_SCAN, 0); 160b032f27cSSam Leffler } else { 161b032f27cSSam Leffler if_printf(vap->iv_ifp, 162b032f27cSSam Leffler "CAC timer on channel %u (%u MHz) expired; " 163b032f27cSSam Leffler "no radar detected\n", 164b032f27cSSam Leffler ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq); 165b032f27cSSam Leffler /* 166b032f27cSSam Leffler * Mark all channels with the current frequency 167b032f27cSSam Leffler * as having completed CAC; this keeps us from 168b032f27cSSam Leffler * doing it again until we change channels. 169b032f27cSSam Leffler */ 170b032f27cSSam Leffler for (i = 0; i < ic->ic_nchans; i++) { 171b032f27cSSam Leffler struct ieee80211_channel *c = &ic->ic_channels[i]; 172b032f27cSSam Leffler if (c->ic_freq == ic->ic_curchan->ic_freq) 173b032f27cSSam Leffler c->ic_state |= IEEE80211_CHANSTATE_CACDONE; 174b032f27cSSam Leffler } 175b032f27cSSam Leffler ieee80211_notify_cac(ic, ic->ic_curchan, 176b032f27cSSam Leffler IEEE80211_NOTIFY_CAC_EXPIRE); 177b032f27cSSam Leffler ieee80211_cac_completeswitch(vap); 178b032f27cSSam Leffler } 179b032f27cSSam Leffler } 180b032f27cSSam Leffler 181b032f27cSSam Leffler /* 182b032f27cSSam Leffler * Initiate the CAC timer. The driver is responsible 183b032f27cSSam Leffler * for setting up the hardware to scan for radar on the 184b032f27cSSam Leffler * channnel, we just handle timing things out. 185b032f27cSSam Leffler */ 186b032f27cSSam Leffler void 187b032f27cSSam Leffler ieee80211_dfs_cac_start(struct ieee80211vap *vap) 188b032f27cSSam Leffler { 189b032f27cSSam Leffler struct ieee80211com *ic = vap->iv_ic; 190b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 191b032f27cSSam Leffler 192b032f27cSSam Leffler IEEE80211_LOCK_ASSERT(ic); 193b032f27cSSam Leffler 194b032f27cSSam Leffler callout_reset(&dfs->cac_timer, CAC_TIMEOUT, cac_timeout, vap); 195b032f27cSSam Leffler if_printf(vap->iv_ifp, "start %d second CAC timer on channel %u (%u MHz)\n", 196b032f27cSSam Leffler ticks_to_secs(CAC_TIMEOUT), 197b032f27cSSam Leffler ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq); 198b032f27cSSam Leffler ieee80211_notify_cac(ic, ic->ic_curchan, IEEE80211_NOTIFY_CAC_START); 199b032f27cSSam Leffler } 200b032f27cSSam Leffler 201b032f27cSSam Leffler /* 202b032f27cSSam Leffler * Clear the CAC timer. 203b032f27cSSam Leffler */ 204b032f27cSSam Leffler void 205b032f27cSSam Leffler ieee80211_dfs_cac_stop(struct ieee80211vap *vap) 206b032f27cSSam Leffler { 207b032f27cSSam Leffler struct ieee80211com *ic = vap->iv_ic; 208b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 209b032f27cSSam Leffler 210b032f27cSSam Leffler IEEE80211_LOCK_ASSERT(ic); 211b032f27cSSam Leffler 212b032f27cSSam Leffler /* NB: racey but not important */ 213b032f27cSSam Leffler if (callout_pending(&dfs->cac_timer)) { 214b032f27cSSam Leffler if_printf(vap->iv_ifp, "stop CAC timer on channel %u (%u MHz)\n", 215b032f27cSSam Leffler ic->ic_curchan->ic_ieee, ic->ic_curchan->ic_freq); 216b032f27cSSam Leffler ieee80211_notify_cac(ic, ic->ic_curchan, 217b032f27cSSam Leffler IEEE80211_NOTIFY_CAC_STOP); 218b032f27cSSam Leffler } 219b032f27cSSam Leffler callout_stop(&dfs->cac_timer); 220b032f27cSSam Leffler } 221b032f27cSSam Leffler 222b032f27cSSam Leffler void 223b032f27cSSam Leffler ieee80211_dfs_cac_clear(struct ieee80211com *ic, 224b032f27cSSam Leffler const struct ieee80211_channel *chan) 225b032f27cSSam Leffler { 226b032f27cSSam Leffler int i; 227b032f27cSSam Leffler 228b032f27cSSam Leffler for (i = 0; i < ic->ic_nchans; i++) { 229b032f27cSSam Leffler struct ieee80211_channel *c = &ic->ic_channels[i]; 230b032f27cSSam Leffler if (c->ic_freq == chan->ic_freq) 231b032f27cSSam Leffler c->ic_state &= ~IEEE80211_CHANSTATE_CACDONE; 232b032f27cSSam Leffler } 233b032f27cSSam Leffler } 234b032f27cSSam Leffler 235b032f27cSSam Leffler static void 236b032f27cSSam Leffler dfs_timeout(void *arg) 237b032f27cSSam Leffler { 238b032f27cSSam Leffler struct ieee80211com *ic = arg; 239b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 240b032f27cSSam Leffler struct ieee80211_channel *c; 241b032f27cSSam Leffler int i, oldest, now; 242b032f27cSSam Leffler 24392c4a81cSSam Leffler IEEE80211_LOCK_ASSERT(ic); 24492c4a81cSSam Leffler 245b032f27cSSam Leffler now = oldest = ticks; 246b032f27cSSam Leffler for (i = 0; i < ic->ic_nchans; i++) { 247b032f27cSSam Leffler c = &ic->ic_channels[i]; 248b032f27cSSam Leffler if (IEEE80211_IS_CHAN_RADAR(c)) { 249b8e29e06SAdrian Chadd if (ieee80211_time_after_eq(now, dfs->nol_event[i]+NOL_TIMEOUT)) { 250b032f27cSSam Leffler c->ic_state &= ~IEEE80211_CHANSTATE_RADAR; 251b032f27cSSam Leffler if (c->ic_state & IEEE80211_CHANSTATE_NORADAR) { 252b032f27cSSam Leffler /* 253b032f27cSSam Leffler * NB: do this here so we get only one 254b032f27cSSam Leffler * msg instead of one for every channel 255b032f27cSSam Leffler * table entry. 256b032f27cSSam Leffler */ 257c8f5794eSGleb Smirnoff ic_printf(ic, "radar on channel %u " 258c8f5794eSGleb Smirnoff "(%u MHz) cleared after timeout\n", 259b032f27cSSam Leffler c->ic_ieee, c->ic_freq); 260b032f27cSSam Leffler /* notify user space */ 261b032f27cSSam Leffler c->ic_state &= 262b032f27cSSam Leffler ~IEEE80211_CHANSTATE_NORADAR; 263b032f27cSSam Leffler ieee80211_notify_radar(ic, c); 264b032f27cSSam Leffler } 265b032f27cSSam Leffler } else if (dfs->nol_event[i] < oldest) 266b032f27cSSam Leffler oldest = dfs->nol_event[i]; 267b032f27cSSam Leffler } 268b032f27cSSam Leffler } 269b032f27cSSam Leffler if (oldest != now) { 270b032f27cSSam Leffler /* arrange to process next channel up for a status change */ 2718460188cSSam Leffler callout_schedule(&dfs->nol_timer, oldest + NOL_TIMEOUT - now); 272b032f27cSSam Leffler } 273b032f27cSSam Leffler } 274b032f27cSSam Leffler 275b032f27cSSam Leffler static void 276c8f5794eSGleb Smirnoff announce_radar(struct ieee80211com *ic, const struct ieee80211_channel *curchan, 277b032f27cSSam Leffler const struct ieee80211_channel *newchan) 278b032f27cSSam Leffler { 279b032f27cSSam Leffler if (newchan == NULL) 280c8f5794eSGleb Smirnoff ic_printf(ic, "radar detected on channel %u (%u MHz)\n", 281b032f27cSSam Leffler curchan->ic_ieee, curchan->ic_freq); 282b032f27cSSam Leffler else 283c8f5794eSGleb Smirnoff ic_printf(ic, "radar detected on channel %u (%u MHz), " 284b032f27cSSam Leffler "moving to channel %u (%u MHz)\n", 285b032f27cSSam Leffler curchan->ic_ieee, curchan->ic_freq, 286b032f27cSSam Leffler newchan->ic_ieee, newchan->ic_freq); 287b032f27cSSam Leffler } 288b032f27cSSam Leffler 289b032f27cSSam Leffler /* 290b032f27cSSam Leffler * Handle a radar detection event on a channel. The channel is 291b032f27cSSam Leffler * added to the NOL list and we record the time of the event. 292b032f27cSSam Leffler * Entries are aged out after NOL_TIMEOUT. If radar was 293b032f27cSSam Leffler * detected while doing CAC we force a state/channel change. 294b032f27cSSam Leffler * Otherwise radar triggers a channel switch using the CSA 295b032f27cSSam Leffler * mechanism (when the channel is the bss channel). 296b032f27cSSam Leffler */ 297b032f27cSSam Leffler void 298b032f27cSSam Leffler ieee80211_dfs_notify_radar(struct ieee80211com *ic, struct ieee80211_channel *chan) 299b032f27cSSam Leffler { 300b032f27cSSam Leffler struct ieee80211_dfs_state *dfs = &ic->ic_dfs; 301b032f27cSSam Leffler int i, now; 302b032f27cSSam Leffler 303b032f27cSSam Leffler IEEE80211_LOCK_ASSERT(ic); 304b032f27cSSam Leffler 305b032f27cSSam Leffler /* 30662f8a13aSAdrian Chadd * If doing DFS debugging (mode 2), don't bother 30762f8a13aSAdrian Chadd * running the rest of this function. 30862f8a13aSAdrian Chadd * 30962f8a13aSAdrian Chadd * Simply announce the presence of the radar and continue 31062f8a13aSAdrian Chadd * along merrily. 31162f8a13aSAdrian Chadd */ 31262f8a13aSAdrian Chadd if (ieee80211_dfs_debug == DFS_DBG_NOCSANOL) { 313c8f5794eSGleb Smirnoff announce_radar(ic, chan, chan); 31462f8a13aSAdrian Chadd ieee80211_notify_radar(ic, chan); 31562f8a13aSAdrian Chadd return; 31662f8a13aSAdrian Chadd } 31762f8a13aSAdrian Chadd 31862f8a13aSAdrian Chadd /* 31962f8a13aSAdrian Chadd * Don't mark the channel and don't put it into NOL 32062f8a13aSAdrian Chadd * if we're doing DFS debugging. 32162f8a13aSAdrian Chadd */ 32262f8a13aSAdrian Chadd if (ieee80211_dfs_debug == DFS_DBG_NONE) { 32362f8a13aSAdrian Chadd /* 324b032f27cSSam Leffler * Mark all entries with this frequency. Notify user 325b032f27cSSam Leffler * space and arrange for notification when the radar 326b032f27cSSam Leffler * indication is cleared. Then kick the NOL processing 327b032f27cSSam Leffler * thread if not already running. 328b032f27cSSam Leffler */ 329b032f27cSSam Leffler now = ticks; 330b032f27cSSam Leffler for (i = 0; i < ic->ic_nchans; i++) { 331b032f27cSSam Leffler struct ieee80211_channel *c = &ic->ic_channels[i]; 332b032f27cSSam Leffler if (c->ic_freq == chan->ic_freq) { 333b032f27cSSam Leffler c->ic_state &= ~IEEE80211_CHANSTATE_CACDONE; 334b032f27cSSam Leffler c->ic_state |= IEEE80211_CHANSTATE_RADAR; 335b032f27cSSam Leffler dfs->nol_event[i] = now; 336b032f27cSSam Leffler } 337b032f27cSSam Leffler } 338b032f27cSSam Leffler ieee80211_notify_radar(ic, chan); 339b032f27cSSam Leffler chan->ic_state |= IEEE80211_CHANSTATE_NORADAR; 340b032f27cSSam Leffler if (!callout_pending(&dfs->nol_timer)) 34162f8a13aSAdrian Chadd callout_reset(&dfs->nol_timer, NOL_TIMEOUT, 34262f8a13aSAdrian Chadd dfs_timeout, ic); 34362f8a13aSAdrian Chadd } 344b032f27cSSam Leffler 345b032f27cSSam Leffler /* 346b032f27cSSam Leffler * If radar is detected on the bss channel while 347b032f27cSSam Leffler * doing CAC; force a state change by scheduling the 348b032f27cSSam Leffler * callout to be dispatched asap. Otherwise, if this 349b032f27cSSam Leffler * event is for the bss channel then we must quiet 350b032f27cSSam Leffler * traffic and schedule a channel switch. 351b032f27cSSam Leffler * 352b032f27cSSam Leffler * Note this allows us to receive notification about 353b032f27cSSam Leffler * channels other than the bss channel; not sure 354b032f27cSSam Leffler * that can/will happen but it's simple to support. 355b032f27cSSam Leffler */ 356b032f27cSSam Leffler if (chan == ic->ic_bsschan) { 357b032f27cSSam Leffler /* XXX need a way to defer to user app */ 35862f8a13aSAdrian Chadd 35962f8a13aSAdrian Chadd /* 36062f8a13aSAdrian Chadd * Don't flip over to a new channel if 36162f8a13aSAdrian Chadd * we are currently doing DFS debugging. 36262f8a13aSAdrian Chadd */ 36362f8a13aSAdrian Chadd if (ieee80211_dfs_debug == DFS_DBG_NONE) 364b032f27cSSam Leffler dfs->newchan = ieee80211_dfs_pickchannel(ic); 36562f8a13aSAdrian Chadd else 36662f8a13aSAdrian Chadd dfs->newchan = chan; 367b032f27cSSam Leffler 368c8f5794eSGleb Smirnoff announce_radar(ic, chan, dfs->newchan); 369b032f27cSSam Leffler 370b032f27cSSam Leffler if (callout_pending(&dfs->cac_timer)) 3715c9b0f1dSSam Leffler callout_schedule(&dfs->cac_timer, 0); 372b032f27cSSam Leffler else if (dfs->newchan != NULL) { 373b032f27cSSam Leffler /* XXX mode 1, switch count 2 */ 374b032f27cSSam Leffler /* XXX calculate switch count based on max 375b032f27cSSam Leffler switch time and beacon interval? */ 376b032f27cSSam Leffler ieee80211_csa_startswitch(ic, dfs->newchan, 1, 2); 377b032f27cSSam Leffler } else { 378b032f27cSSam Leffler /* 379b032f27cSSam Leffler * Spec says to stop all transmissions and 380b032f27cSSam Leffler * wait on the current channel for an entry 381b032f27cSSam Leffler * on the NOL to expire. 382b032f27cSSam Leffler */ 383b032f27cSSam Leffler /*XXX*/ 384c8f5794eSGleb Smirnoff ic_printf(ic, "%s: No free channels; waiting for entry " 385e1ab183cSAdrian Chadd "on NOL to expire\n", __func__); 386b032f27cSSam Leffler } 387b032f27cSSam Leffler } else { 388b032f27cSSam Leffler /* 389b032f27cSSam Leffler * Issue rate-limited console msgs. 390b032f27cSSam Leffler */ 391b032f27cSSam Leffler if (dfs->lastchan != chan) { 392b032f27cSSam Leffler dfs->lastchan = chan; 393b032f27cSSam Leffler dfs->cureps = 0; 394c8f5794eSGleb Smirnoff announce_radar(ic, chan, NULL); 395b032f27cSSam Leffler } else if (ppsratecheck(&dfs->lastevent, &dfs->cureps, 1)) { 396c8f5794eSGleb Smirnoff announce_radar(ic, chan, NULL); 397b032f27cSSam Leffler } 398b032f27cSSam Leffler } 399b032f27cSSam Leffler } 400b032f27cSSam Leffler 401b032f27cSSam Leffler struct ieee80211_channel * 402b032f27cSSam Leffler ieee80211_dfs_pickchannel(struct ieee80211com *ic) 403b032f27cSSam Leffler { 404b032f27cSSam Leffler struct ieee80211_channel *c; 405b032f27cSSam Leffler int i, flags; 406b032f27cSSam Leffler uint16_t v; 407b032f27cSSam Leffler 408b032f27cSSam Leffler /* 409b032f27cSSam Leffler * Consult the scan cache first. 410b032f27cSSam Leffler */ 411b032f27cSSam Leffler flags = ic->ic_curchan->ic_flags & IEEE80211_CHAN_ALL; 412b032f27cSSam Leffler /* 413b032f27cSSam Leffler * XXX if curchan is HT this will never find a channel 414b032f27cSSam Leffler * XXX 'cuz we scan only legacy channels 415b032f27cSSam Leffler */ 416b032f27cSSam Leffler c = ieee80211_scan_pickchannel(ic, flags); 417b032f27cSSam Leffler if (c != NULL) 418b032f27cSSam Leffler return c; 419b032f27cSSam Leffler /* 420b032f27cSSam Leffler * No channel found in scan cache; select a compatible 421b032f27cSSam Leffler * one at random (skipping channels where radar has 422b032f27cSSam Leffler * been detected). 423b032f27cSSam Leffler */ 424*af7d9f8eSBjoern A. Zeeb net80211_get_random_bytes(&v, sizeof(v)); 425b032f27cSSam Leffler v %= ic->ic_nchans; 426b032f27cSSam Leffler for (i = v; i < ic->ic_nchans; i++) { 427b032f27cSSam Leffler c = &ic->ic_channels[i]; 428b032f27cSSam Leffler if (!IEEE80211_IS_CHAN_RADAR(c) && 429b032f27cSSam Leffler (c->ic_flags & flags) == flags) 430b032f27cSSam Leffler return c; 431b032f27cSSam Leffler } 432b032f27cSSam Leffler for (i = 0; i < v; i++) { 433b032f27cSSam Leffler c = &ic->ic_channels[i]; 434b032f27cSSam Leffler if (!IEEE80211_IS_CHAN_RADAR(c) && 435b032f27cSSam Leffler (c->ic_flags & flags) == flags) 436b032f27cSSam Leffler return c; 437b032f27cSSam Leffler } 438c8f5794eSGleb Smirnoff ic_printf(ic, "HELP, no channel located to switch to!\n"); 439b032f27cSSam Leffler return NULL; 440b032f27cSSam Leffler } 441