diff options
Diffstat (limited to 'freebsd/sys/net80211/ieee80211_scan_sta.c')
| -rw-r--r-- | freebsd/sys/net80211/ieee80211_scan_sta.c | 1928 |
1 files changed, 1928 insertions, 0 deletions
diff --git a/freebsd/sys/net80211/ieee80211_scan_sta.c b/freebsd/sys/net80211/ieee80211_scan_sta.c new file mode 100644 index 00000000..aa9d67ec --- /dev/null +++ b/freebsd/sys/net80211/ieee80211_scan_sta.c @@ -0,0 +1,1928 @@ +#include <freebsd/machine/rtems-bsd-config.h> + +/*- + * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <freebsd/sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +/* + * IEEE 802.11 station scanning support. + */ +#include <freebsd/local/opt_wlan.h> + +#include <freebsd/sys/param.h> +#include <freebsd/sys/systm.h> +#include <freebsd/sys/kernel.h> +#include <freebsd/sys/module.h> + +#include <freebsd/sys/socket.h> + +#include <freebsd/net/if.h> +#include <freebsd/net/if_media.h> +#include <freebsd/net/ethernet.h> + +#include <freebsd/net80211/ieee80211_var.h> +#include <freebsd/net80211/ieee80211_input.h> +#include <freebsd/net80211/ieee80211_regdomain.h> +#ifdef IEEE80211_SUPPORT_TDMA +#include <freebsd/net80211/ieee80211_tdma.h> +#endif +#ifdef IEEE80211_SUPPORT_MESH +#include <freebsd/net80211/ieee80211_mesh.h> +#endif + +#include <freebsd/net/bpf.h> + +/* + * Parameters for managing cache entries: + * + * o a station with STA_FAILS_MAX failures is not considered + * when picking a candidate + * o a station that hasn't had an update in STA_PURGE_SCANS + * (background) scans is discarded + * o after STA_FAILS_AGE seconds we clear the failure count + */ +#define STA_FAILS_MAX 2 /* assoc failures before ignored */ +#define STA_FAILS_AGE (2*60) /* time before clearing fails (secs) */ +#define STA_PURGE_SCANS 2 /* age for purging entries (scans) */ + +/* XXX tunable */ +#define STA_RSSI_MIN 8 /* min acceptable rssi */ +#define STA_RSSI_MAX 40 /* max rssi for comparison */ + +struct sta_entry { + struct ieee80211_scan_entry base; + TAILQ_ENTRY(sta_entry) se_list; + LIST_ENTRY(sta_entry) se_hash; + uint8_t se_fails; /* failure to associate count */ + uint8_t se_seen; /* seen during current scan */ + uint8_t se_notseen; /* not seen in previous scans */ + uint8_t se_flags; +#define STA_DEMOTE11B 0x01 /* match w/ demoted 11b chan */ + uint32_t se_avgrssi; /* LPF rssi state */ + unsigned long se_lastupdate; /* time of last update */ + unsigned long se_lastfail; /* time of last failure */ + unsigned long se_lastassoc; /* time of last association */ + u_int se_scangen; /* iterator scan gen# */ + u_int se_countrygen; /* gen# of last cc notify */ +}; + +#define STA_HASHSIZE 32 +/* simple hash is enough for variation of macaddr */ +#define STA_HASH(addr) \ + (((const uint8_t *)(addr))[IEEE80211_ADDR_LEN - 1] % STA_HASHSIZE) + +#define MAX_IEEE_CHAN 256 /* max acceptable IEEE chan # */ +CTASSERT(MAX_IEEE_CHAN >= 256); + +struct sta_table { + ieee80211_scan_table_lock_t st_lock; /* on scan table */ + TAILQ_HEAD(, sta_entry) st_entry; /* all entries */ + LIST_HEAD(, sta_entry) st_hash[STA_HASHSIZE]; + struct mtx st_scanlock; /* on st_scaniter */ + u_int st_scaniter; /* gen# for iterator */ + u_int st_scangen; /* scan generation # */ + int st_newscan; + /* ap-related state */ + int st_maxrssi[MAX_IEEE_CHAN]; +}; + +static void sta_flush_table(struct sta_table *); +/* + * match_bss returns a bitmask describing if an entry is suitable + * for use. If non-zero the entry was deemed not suitable and it's + * contents explains why. The following flags are or'd to to this + * mask and can be used to figure out why the entry was rejected. + */ +#define MATCH_CHANNEL 0x00001 /* channel mismatch */ +#define MATCH_CAPINFO 0x00002 /* capabilities mismatch, e.g. no ess */ +#define MATCH_PRIVACY 0x00004 /* privacy mismatch */ +#define MATCH_RATE 0x00008 /* rate set mismatch */ +#define MATCH_SSID 0x00010 /* ssid mismatch */ +#define MATCH_BSSID 0x00020 /* bssid mismatch */ +#define MATCH_FAILS 0x00040 /* too many failed auth attempts */ +#define MATCH_NOTSEEN 0x00080 /* not seen in recent scans */ +#define MATCH_RSSI 0x00100 /* rssi deemed too low to use */ +#define MATCH_CC 0x00200 /* country code mismatch */ +#define MATCH_TDMA_NOIE 0x00400 /* no TDMA ie */ +#define MATCH_TDMA_NOTMASTER 0x00800 /* not TDMA master */ +#define MATCH_TDMA_NOSLOT 0x01000 /* all TDMA slots occupied */ +#define MATCH_TDMA_LOCAL 0x02000 /* local address */ +#define MATCH_TDMA_VERSION 0x04000 /* protocol version mismatch */ +#define MATCH_MESH_NOID 0x10000 /* no MESHID ie */ +#define MATCH_MESHID 0x20000 /* meshid mismatch */ +static int match_bss(struct ieee80211vap *, + const struct ieee80211_scan_state *, struct sta_entry *, int); +static void adhoc_age(struct ieee80211_scan_state *); + +static __inline int +isocmp(const uint8_t cc1[], const uint8_t cc2[]) +{ + return (cc1[0] == cc2[0] && cc1[1] == cc2[1]); +} + +/* number of references from net80211 layer */ +static int nrefs = 0; +/* + * Module glue. + */ +IEEE80211_SCANNER_MODULE(sta, 1); + +/* + * Attach prior to any scanning work. + */ +static int +sta_attach(struct ieee80211_scan_state *ss) +{ + struct sta_table *st; + + st = (struct sta_table *) malloc(sizeof(struct sta_table), + M_80211_SCAN, M_NOWAIT | M_ZERO); + if (st == NULL) + return 0; + IEEE80211_SCAN_TABLE_LOCK_INIT(st, "scantable"); + mtx_init(&st->st_scanlock, "scangen", "802.11 scangen", MTX_DEF); + TAILQ_INIT(&st->st_entry); + ss->ss_priv = st; + nrefs++; /* NB: we assume caller locking */ + return 1; +} + +/* + * Cleanup any private state. + */ +static int +sta_detach(struct ieee80211_scan_state *ss) +{ + struct sta_table *st = ss->ss_priv; + + if (st != NULL) { + sta_flush_table(st); + IEEE80211_SCAN_TABLE_LOCK_DESTROY(st); + mtx_destroy(&st->st_scanlock); + free(st, M_80211_SCAN); + KASSERT(nrefs > 0, ("imbalanced attach/detach")); + nrefs--; /* NB: we assume caller locking */ + } + return 1; +} + +/* + * Flush all per-scan state. + */ +static int +sta_flush(struct ieee80211_scan_state *ss) +{ + struct sta_table *st = ss->ss_priv; + + IEEE80211_SCAN_TABLE_LOCK(st); + sta_flush_table(st); + IEEE80211_SCAN_TABLE_UNLOCK(st); + ss->ss_last = 0; + return 0; +} + +/* + * Flush all entries in the scan cache. + */ +static void +sta_flush_table(struct sta_table *st) +{ + struct sta_entry *se, *next; + + TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { + TAILQ_REMOVE(&st->st_entry, se, se_list); + LIST_REMOVE(se, se_hash); + ieee80211_ies_cleanup(&se->base.se_ies); + free(se, M_80211_SCAN); + } + memset(st->st_maxrssi, 0, sizeof(st->st_maxrssi)); +} + +/* + * Process a beacon or probe response frame; create an + * entry in the scan cache or update any previous entry. + */ +static int +sta_add(struct ieee80211_scan_state *ss, + const struct ieee80211_scanparams *sp, + const struct ieee80211_frame *wh, + int subtype, int rssi, int noise) +{ +#define ISPROBE(_st) ((_st) == IEEE80211_FC0_SUBTYPE_PROBE_RESP) +#define PICK1ST(_ss) \ + ((ss->ss_flags & (IEEE80211_SCAN_PICK1ST | IEEE80211_SCAN_GOTPICK)) == \ + IEEE80211_SCAN_PICK1ST) + struct sta_table *st = ss->ss_priv; + const uint8_t *macaddr = wh->i_addr2; + struct ieee80211vap *vap = ss->ss_vap; + struct ieee80211com *ic = vap->iv_ic; + struct sta_entry *se; + struct ieee80211_scan_entry *ise; + int hash; + + hash = STA_HASH(macaddr); + + IEEE80211_SCAN_TABLE_LOCK(st); + LIST_FOREACH(se, &st->st_hash[hash], se_hash) + if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) + goto found; + se = (struct sta_entry *) malloc(sizeof(struct sta_entry), + M_80211_SCAN, M_NOWAIT | M_ZERO); + if (se == NULL) { + IEEE80211_SCAN_TABLE_UNLOCK(st); + return 0; + } + se->se_scangen = st->st_scaniter-1; + se->se_avgrssi = IEEE80211_RSSI_DUMMY_MARKER; + IEEE80211_ADDR_COPY(se->base.se_macaddr, macaddr); + TAILQ_INSERT_TAIL(&st->st_entry, se, se_list); + LIST_INSERT_HEAD(&st->st_hash[hash], se, se_hash); +found: + ise = &se->base; + /* XXX ap beaconing multiple ssid w/ same bssid */ + if (sp->ssid[1] != 0 && + (ISPROBE(subtype) || ise->se_ssid[1] == 0)) + memcpy(ise->se_ssid, sp->ssid, 2+sp->ssid[1]); + KASSERT(sp->rates[1] <= IEEE80211_RATE_MAXSIZE, + ("rate set too large: %u", sp->rates[1])); + memcpy(ise->se_rates, sp->rates, 2+sp->rates[1]); + if (sp->xrates != NULL) { + /* XXX validate xrates[1] */ + KASSERT(sp->xrates[1] <= IEEE80211_RATE_MAXSIZE, + ("xrate set too large: %u", sp->xrates[1])); + memcpy(ise->se_xrates, sp->xrates, 2+sp->xrates[1]); + } else + ise->se_xrates[1] = 0; + IEEE80211_ADDR_COPY(ise->se_bssid, wh->i_addr3); + if ((sp->status & IEEE80211_BPARSE_OFFCHAN) == 0) { + /* + * Record rssi data using extended precision LPF filter. + * + * NB: use only on-channel data to insure we get a good + * estimate of the signal we'll see when associated. + */ + IEEE80211_RSSI_LPF(se->se_avgrssi, rssi); + ise->se_rssi = IEEE80211_RSSI_GET(se->se_avgrssi); + ise->se_noise = noise; + } + memcpy(ise->se_tstamp.data, sp->tstamp, sizeof(ise->se_tstamp)); + ise->se_intval = sp->bintval; + ise->se_capinfo = sp->capinfo; +#ifdef IEEE80211_SUPPORT_MESH + if (sp->meshid != NULL && sp->meshid[1] != 0) + memcpy(ise->se_meshid, sp->meshid, 2+sp->meshid[1]); +#endif + /* + * Beware of overriding se_chan for frames seen + * off-channel; this can cause us to attempt an + * association on the wrong channel. + */ + if (sp->status & IEEE80211_BPARSE_OFFCHAN) { + struct ieee80211_channel *c; + /* + * Off-channel, locate the home/bss channel for the sta + * using the value broadcast in the DSPARMS ie. We know + * sp->chan has this value because it's used to calculate + * IEEE80211_BPARSE_OFFCHAN. + */ + c = ieee80211_find_channel_byieee(ic, sp->chan, + ic->ic_curchan->ic_flags); + if (c != NULL) { + ise->se_chan = c; + } else if (ise->se_chan == NULL) { + /* should not happen, pick something */ + ise->se_chan = ic->ic_curchan; + } + } else + ise->se_chan = ic->ic_curchan; + ise->se_fhdwell = sp->fhdwell; + ise->se_fhindex = sp->fhindex; + ise->se_erp = sp->erp; + ise->se_timoff = sp->timoff; + if (sp->tim != NULL) { + const struct ieee80211_tim_ie *tim = + (const struct ieee80211_tim_ie *) sp->tim; + ise->se_dtimperiod = tim->tim_period; + } + if (sp->country != NULL) { + const struct ieee80211_country_ie *cie = + (const struct ieee80211_country_ie *) sp->country; + /* + * If 11d is enabled and we're attempting to join a bss + * that advertises it's country code then compare our + * current settings to what we fetched from the country ie. + * If our country code is unspecified or different then + * dispatch an event to user space that identifies the + * country code so our regdomain config can be changed. + */ + /* XXX only for STA mode? */ + if ((IEEE80211_IS_CHAN_11D(ise->se_chan) || + (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && + (ic->ic_regdomain.country == CTRY_DEFAULT || + !isocmp(cie->cc, ic->ic_regdomain.isocc))) { + /* only issue one notify event per scan */ + if (se->se_countrygen != st->st_scangen) { + ieee80211_notify_country(vap, ise->se_bssid, + cie->cc); + se->se_countrygen = st->st_scangen; + } + } + ise->se_cc[0] = cie->cc[0]; + ise->se_cc[1] = cie->cc[1]; + } + /* NB: no need to setup ie ptrs; they are not (currently) used */ + (void) ieee80211_ies_init(&ise->se_ies, sp->ies, sp->ies_len); + + /* clear failure count after STA_FAIL_AGE passes */ + if (se->se_fails && (ticks - se->se_lastfail) > STA_FAILS_AGE*hz) { + se->se_fails = 0; + IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, macaddr, + "%s: fails %u", __func__, se->se_fails); + } + + se->se_lastupdate = ticks; /* update time */ + se->se_seen = 1; + se->se_notseen = 0; + + KASSERT(sizeof(sp->bchan) == 1, ("bchan size")); + if (rssi > st->st_maxrssi[sp->bchan]) + st->st_maxrssi[sp->bchan] = rssi; + + IEEE80211_SCAN_TABLE_UNLOCK(st); + + /* + * If looking for a quick choice and nothing's + * been found check here. + */ + if (PICK1ST(ss) && match_bss(vap, ss, se, IEEE80211_MSG_SCAN) == 0) + ss->ss_flags |= IEEE80211_SCAN_GOTPICK; + + return 1; +#undef PICK1ST +#undef ISPROBE +} + +/* + * Check if a channel is excluded by user request. + */ +static int +isexcluded(struct ieee80211vap *vap, const struct ieee80211_channel *c) +{ + return (isclr(vap->iv_ic->ic_chan_active, c->ic_ieee) || + (vap->iv_des_chan != IEEE80211_CHAN_ANYC && + c->ic_freq != vap->iv_des_chan->ic_freq)); +} + +static struct ieee80211_channel * +find11gchannel(struct ieee80211com *ic, int i, int freq) +{ + struct ieee80211_channel *c; + int j; + + /* + * The normal ordering in the channel list is b channel + * immediately followed by g so optimize the search for + * this. We'll still do a full search just in case. + */ + for (j = i+1; j < ic->ic_nchans; j++) { + c = &ic->ic_channels[j]; + if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) + return c; + } + for (j = 0; j < i; j++) { + c = &ic->ic_channels[j]; + if (c->ic_freq == freq && IEEE80211_IS_CHAN_G(c)) + return c; + } + return NULL; +} + +static const u_int chanflags[IEEE80211_MODE_MAX] = { + [IEEE80211_MODE_AUTO] = IEEE80211_CHAN_B, + [IEEE80211_MODE_11A] = IEEE80211_CHAN_A, + [IEEE80211_MODE_11B] = IEEE80211_CHAN_B, + [IEEE80211_MODE_11G] = IEEE80211_CHAN_G, + [IEEE80211_MODE_FH] = IEEE80211_CHAN_FHSS, + /* check base channel */ + [IEEE80211_MODE_TURBO_A] = IEEE80211_CHAN_A, + [IEEE80211_MODE_TURBO_G] = IEEE80211_CHAN_G, + [IEEE80211_MODE_STURBO_A] = IEEE80211_CHAN_ST, + [IEEE80211_MODE_HALF] = IEEE80211_CHAN_HALF, + [IEEE80211_MODE_QUARTER] = IEEE80211_CHAN_QUARTER, + /* check legacy */ + [IEEE80211_MODE_11NA] = IEEE80211_CHAN_A, + [IEEE80211_MODE_11NG] = IEEE80211_CHAN_G, +}; + +static void +add_channels(struct ieee80211vap *vap, + struct ieee80211_scan_state *ss, + enum ieee80211_phymode mode, const uint16_t freq[], int nfreq) +{ +#define N(a) (sizeof(a) / sizeof(a[0])) + struct ieee80211com *ic = vap->iv_ic; + struct ieee80211_channel *c, *cg; + u_int modeflags; + int i; + + KASSERT(mode < N(chanflags), ("Unexpected mode %u", mode)); + modeflags = chanflags[mode]; + for (i = 0; i < nfreq; i++) { + if (ss->ss_last >= IEEE80211_SCAN_MAX) + break; + + c = ieee80211_find_channel(ic, freq[i], modeflags); + if (c == NULL || isexcluded(vap, c)) + continue; + if (mode == IEEE80211_MODE_AUTO) { + /* + * XXX special-case 11b/g channels so we select + * the g channel if both are present. + */ + if (IEEE80211_IS_CHAN_B(c) && + (cg = find11gchannel(ic, i, c->ic_freq)) != NULL) + c = cg; + } + ss->ss_chans[ss->ss_last++] = c; + } +#undef N +} + +struct scanlist { + uint16_t mode; + uint16_t count; + const uint16_t *list; +}; + +static int +checktable(const struct scanlist *scan, const struct ieee80211_channel *c) +{ + int i; + + for (; scan->list != NULL; scan++) { + for (i = 0; i < scan->count; i++) + if (scan->list[i] == c->ic_freq) + return 1; + } + return 0; +} + +static int +onscanlist(const struct ieee80211_scan_state *ss, + const struct ieee80211_channel *c) +{ + int i; + + for (i = 0; i < ss->ss_last; i++) + if (ss->ss_chans[i] == c) + return 1; + return 0; +} + +static void +sweepchannels(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, + const struct scanlist table[]) +{ + struct ieee80211com *ic = vap->iv_ic; + struct ieee80211_channel *c; + int i; + + for (i = 0; i < ic->ic_nchans; i++) { + if (ss->ss_last >= IEEE80211_SCAN_MAX) + break; + + c = &ic->ic_channels[i]; + /* + * Ignore dynamic turbo channels; we scan them + * in normal mode (i.e. not boosted). Likewise + * for HT channels, they get scanned using + * legacy rates. + */ + if (IEEE80211_IS_CHAN_DTURBO(c) || IEEE80211_IS_CHAN_HT(c)) + continue; + + /* + * If a desired mode was specified, scan only + * channels that satisfy that constraint. + */ + if (vap->iv_des_mode != IEEE80211_MODE_AUTO && + vap->iv_des_mode != ieee80211_chan2mode(c)) + continue; + + /* + * Skip channels excluded by user request. + */ + if (isexcluded(vap, c)) + continue; + + /* + * Add the channel unless it is listed in the + * fixed scan order tables. This insures we + * don't sweep back in channels we filtered out + * above. + */ + if (checktable(table, c)) + continue; + + /* Add channel to scanning list. */ + ss->ss_chans[ss->ss_last++] = c; + } + /* + * Explicitly add any desired channel if: + * - not already on the scan list + * - allowed by any desired mode constraint + * - there is space in the scan list + * This allows the channel to be used when the filtering + * mechanisms would otherwise elide it (e.g HT, turbo). + */ + c = vap->iv_des_chan; + if (c != IEEE80211_CHAN_ANYC && + !onscanlist(ss, c) && + (vap->iv_des_mode == IEEE80211_MODE_AUTO || + vap->iv_des_mode == ieee80211_chan2mode(c)) && + ss->ss_last < IEEE80211_SCAN_MAX) + ss->ss_chans[ss->ss_last++] = c; +} + +static void +makescanlist(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, + const struct scanlist table[]) +{ + const struct scanlist *scan; + enum ieee80211_phymode mode; + + ss->ss_last = 0; + /* + * Use the table of ordered channels to construct the list + * of channels for scanning. Any channels in the ordered + * list not in the master list will be discarded. + */ + for (scan = table; scan->list != NULL; scan++) { + mode = scan->mode; + if (vap->iv_des_mode != IEEE80211_MODE_AUTO) { + /* + * If a desired mode was specified, scan only + * channels that satisfy that constraint. + */ + if (vap->iv_des_mode != mode) { + /* + * The scan table marks 2.4Ghz channels as b + * so if the desired mode is 11g, then use + * the 11b channel list but upgrade the mode. + */ + if (vap->iv_des_mode != IEEE80211_MODE_11G || + mode != IEEE80211_MODE_11B) + continue; + mode = IEEE80211_MODE_11G; /* upgrade */ + } + } else { + /* + * This lets add_channels upgrade an 11b channel + * to 11g if available. + */ + if (mode == IEEE80211_MODE_11B) + mode = IEEE80211_MODE_AUTO; + } +#ifdef IEEE80211_F_XR + /* XR does not operate on turbo channels */ + if ((vap->iv_flags & IEEE80211_F_XR) && + (mode == IEEE80211_MODE_TURBO_A || + mode == IEEE80211_MODE_TURBO_G || + mode == IEEE80211_MODE_STURBO_A)) + continue; +#endif + /* + * Add the list of the channels; any that are not + * in the master channel list will be discarded. + */ + add_channels(vap, ss, mode, scan->list, scan->count); + } + + /* + * Add the channels from the ic that are not present + * in the table. + */ + sweepchannels(ss, vap, table); +} + +static const uint16_t rcl1[] = /* 8 FCC channel: 52, 56, 60, 64, 36, 40, 44, 48 */ +{ 5260, 5280, 5300, 5320, 5180, 5200, 5220, 5240 }; +static const uint16_t rcl2[] = /* 4 MKK channels: 34, 38, 42, 46 */ +{ 5170, 5190, 5210, 5230 }; +static const uint16_t rcl3[] = /* 2.4Ghz ch: 1,6,11,7,13 */ +{ 2412, 2437, 2462, 2442, 2472 }; +static const uint16_t rcl4[] = /* 5 FCC channel: 149, 153, 161, 165 */ +{ 5745, 5765, 5785, 5805, 5825 }; +static const uint16_t rcl7[] = /* 11 ETSI channel: 100,104,108,112,116,120,124,128,132,136,140 */ +{ 5500, 5520, 5540, 5560, 5580, 5600, 5620, 5640, 5660, 5680, 5700 }; +static const uint16_t rcl8[] = /* 2.4Ghz ch: 2,3,4,5,8,9,10,12 */ +{ 2417, 2422, 2427, 2432, 2447, 2452, 2457, 2467 }; +static const uint16_t rcl9[] = /* 2.4Ghz ch: 14 */ +{ 2484 }; +static const uint16_t rcl10[] = /* Added Korean channels 2312-2372 */ +{ 2312, 2317, 2322, 2327, 2332, 2337, 2342, 2347, 2352, 2357, 2362, 2367, 2372 }; +static const uint16_t rcl11[] = /* Added Japan channels in 4.9/5.0 spectrum */ +{ 5040, 5060, 5080, 4920, 4940, 4960, 4980 }; +#ifdef ATH_TURBO_SCAN +static const uint16_t rcl5[] = /* 3 static turbo channels */ +{ 5210, 5250, 5290 }; +static const uint16_t rcl6[] = /* 2 static turbo channels */ +{ 5760, 5800 }; +static const uint16_t rcl6x[] = /* 4 FCC3 turbo channels */ +{ 5540, 5580, 5620, 5660 }; +static const uint16_t rcl12[] = /* 2.4Ghz Turbo channel 6 */ +{ 2437 }; +static const uint16_t rcl13[] = /* dynamic Turbo channels */ +{ 5200, 5240, 5280, 5765, 5805 }; +#endif /* ATH_TURBO_SCAN */ + +#define X(a) .count = sizeof(a)/sizeof(a[0]), .list = a + +static const struct scanlist staScanTable[] = { + { IEEE80211_MODE_11B, X(rcl3) }, + { IEEE80211_MODE_11A, X(rcl1) }, + { IEEE80211_MODE_11A, X(rcl2) }, + { IEEE80211_MODE_11B, X(rcl8) }, + { IEEE80211_MODE_11B, X(rcl9) }, + { IEEE80211_MODE_11A, X(rcl4) }, +#ifdef ATH_TURBO_SCAN + { IEEE80211_MODE_STURBO_A, X(rcl5) }, + { IEEE80211_MODE_STURBO_A, X(rcl6) }, + { IEEE80211_MODE_TURBO_A, X(rcl6x) }, + { IEEE80211_MODE_TURBO_A, X(rcl13) }, +#endif /* ATH_TURBO_SCAN */ + { IEEE80211_MODE_11A, X(rcl7) }, + { IEEE80211_MODE_11B, X(rcl10) }, + { IEEE80211_MODE_11A, X(rcl11) }, +#ifdef ATH_TURBO_SCAN + { IEEE80211_MODE_TURBO_G, X(rcl12) }, +#endif /* ATH_TURBO_SCAN */ + { .list = NULL } +}; + +/* + * Start a station-mode scan by populating the channel list. + */ +static int +sta_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + + makescanlist(ss, vap, staScanTable); + + if (ss->ss_mindwell == 0) + ss->ss_mindwell = msecs_to_ticks(20); /* 20ms */ + if (ss->ss_maxdwell == 0) + ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ + + st->st_scangen++; + st->st_newscan = 1; + + return 0; +} + +/* + * Restart a scan, typically a bg scan but can + * also be a fg scan that came up empty. + */ +static int +sta_restart(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + + st->st_newscan = 1; + return 0; +} + +/* + * Cancel an ongoing scan. + */ +static int +sta_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + return 0; +} + +/* unalligned little endian access */ +#define LE_READ_2(p) \ + ((uint16_t) \ + ((((const uint8_t *)(p))[0] ) | \ + (((const uint8_t *)(p))[1] << 8))) + +/* + * Demote any supplied 11g channel to 11b. There should + * always be an 11b channel but we check anyway... + */ +static struct ieee80211_channel * +demote11b(struct ieee80211vap *vap, struct ieee80211_channel *chan) +{ + struct ieee80211_channel *c; + + if (IEEE80211_IS_CHAN_ANYG(chan) && + vap->iv_des_mode == IEEE80211_MODE_AUTO) { + c = ieee80211_find_channel(vap->iv_ic, chan->ic_freq, + (chan->ic_flags &~ (IEEE80211_CHAN_PUREG | IEEE80211_CHAN_G)) | + IEEE80211_CHAN_B); + if (c != NULL) + chan = c; + } + return chan; +} + +static int +maxrate(const struct ieee80211_scan_entry *se) +{ + const struct ieee80211_ie_htcap *htcap = + (const struct ieee80211_ie_htcap *) se->se_ies.htcap_ie; + int rmax, r, i; + uint16_t caps; + + rmax = 0; + if (htcap != NULL) { + /* + * HT station; inspect supported MCS and then adjust + * rate by channel width. Could also include short GI + * in this if we want to be extra accurate. + */ + /* XXX assumes MCS15 is max */ + for (i = 15; i >= 0 && isclr(htcap->hc_mcsset, i); i--) + ; + if (i >= 0) { + caps = LE_READ_2(&htcap->hc_cap); + /* XXX short/long GI */ + if (caps & IEEE80211_HTCAP_CHWIDTH40) + rmax = ieee80211_htrates[i].ht40_rate_400ns; + else + rmax = ieee80211_htrates[i].ht40_rate_800ns; + } + } + for (i = 0; i < se->se_rates[1]; i++) { + r = se->se_rates[2+i] & IEEE80211_RATE_VAL; + if (r > rmax) + rmax = r; + } + for (i = 0; i < se->se_xrates[1]; i++) { + r = se->se_xrates[2+i] & IEEE80211_RATE_VAL; + if (r > rmax) + rmax = r; + } + return rmax; +} + +/* + * Compare the capabilities of two entries and decide which is + * more desirable (return >0 if a is considered better). Note + * that we assume compatibility/usability has already been checked + * so we don't need to (e.g. validate whether privacy is supported). + * Used to select the best scan candidate for association in a BSS. + */ +static int +sta_compare(const struct sta_entry *a, const struct sta_entry *b) +{ +#define PREFER(_a,_b,_what) do { \ + if (((_a) ^ (_b)) & (_what)) \ + return ((_a) & (_what)) ? 1 : -1; \ +} while (0) + int maxa, maxb; + int8_t rssia, rssib; + int weight; + + /* privacy support */ + PREFER(a->base.se_capinfo, b->base.se_capinfo, + IEEE80211_CAPINFO_PRIVACY); + + /* compare count of previous failures */ + weight = b->se_fails - a->se_fails; + if (abs(weight) > 1) + return weight; + + /* + * Compare rssi. If the two are considered equivalent + * then fallback to other criteria. We threshold the + * comparisons to avoid selecting an ap purely by rssi + * when both values may be good but one ap is otherwise + * more desirable (e.g. an 11b-only ap with stronger + * signal than an 11g ap). + */ + rssia = MIN(a->base.se_rssi, STA_RSSI_MAX); + rssib = MIN(b->base.se_rssi, STA_RSSI_MAX); + if (abs(rssib - rssia) < 5) { + /* best/max rate preferred if signal level close enough XXX */ + maxa = maxrate(&a->base); + maxb = maxrate(&b->base); + if (maxa != maxb) + return maxa - maxb; + /* XXX use freq for channel preference */ + /* for now just prefer 5Ghz band to all other bands */ + PREFER(IEEE80211_IS_CHAN_5GHZ(a->base.se_chan), + IEEE80211_IS_CHAN_5GHZ(b->base.se_chan), 1); + } + /* all things being equal, use signal level */ + return a->base.se_rssi - b->base.se_rssi; +#undef PREFER +} + +/* + * Check rate set suitability and return the best supported rate. + * XXX inspect MCS for HT + */ +static int +check_rate(struct ieee80211vap *vap, const struct ieee80211_channel *chan, + const struct ieee80211_scan_entry *se) +{ +#define RV(v) ((v) & IEEE80211_RATE_VAL) + const struct ieee80211_rateset *srs; + int i, j, nrs, r, okrate, badrate, fixedrate, ucastrate; + const uint8_t *rs; + + okrate = badrate = 0; + + srs = ieee80211_get_suprates(vap->iv_ic, chan); + nrs = se->se_rates[1]; + rs = se->se_rates+2; + /* XXX MCS */ + ucastrate = vap->iv_txparms[ieee80211_chan2mode(chan)].ucastrate; + fixedrate = IEEE80211_FIXED_RATE_NONE; +again: + for (i = 0; i < nrs; i++) { + r = RV(rs[i]); + badrate = r; + /* + * Check any fixed rate is included. + */ + if (r == ucastrate) + fixedrate = r; + /* + * Check against our supported rates. + */ + for (j = 0; j < srs->rs_nrates; j++) + if (r == RV(srs->rs_rates[j])) { + if (r > okrate) /* NB: track max */ + okrate = r; + break; + } + + if (j == srs->rs_nrates && (rs[i] & IEEE80211_RATE_BASIC)) { + /* + * Don't try joining a BSS, if we don't support + * one of its basic rates. + */ + okrate = 0; + goto back; + } + } + if (rs == se->se_rates+2) { + /* scan xrates too; sort of an algol68-style for loop */ + nrs = se->se_xrates[1]; + rs = se->se_xrates+2; + goto again; + } + +back: + if (okrate == 0 || ucastrate != fixedrate) + return badrate | IEEE80211_RATE_BASIC; + else + return RV(okrate); +#undef RV +} + +static __inline int +match_id(const uint8_t *ie, const uint8_t *val, int len) +{ + return (ie[1] == len && memcmp(ie+2, val, len) == 0); +} + +static int +match_ssid(const uint8_t *ie, + int nssid, const struct ieee80211_scan_ssid ssids[]) +{ + int i; + + for (i = 0; i < nssid; i++) { + if (match_id(ie, ssids[i].ssid, ssids[i].len)) + return 1; + } + return 0; +} + +#ifdef IEEE80211_SUPPORT_TDMA +static int +tdma_isfull(const struct ieee80211_tdma_param *tdma) +{ + int slot, slotcnt; + + slotcnt = tdma->tdma_slotcnt; + for (slot = slotcnt-1; slot >= 0; slot--) + if (isclr(tdma->tdma_inuse, slot)) + return 0; + return 1; +} +#endif /* IEEE80211_SUPPORT_TDMA */ + +/* + * Test a scan candidate for suitability/compatibility. + */ +static int +match_bss(struct ieee80211vap *vap, + const struct ieee80211_scan_state *ss, struct sta_entry *se0, + int debug) +{ + struct ieee80211com *ic = vap->iv_ic; + struct ieee80211_scan_entry *se = &se0->base; + uint8_t rate; + int fail; + + fail = 0; + if (isclr(ic->ic_chan_active, ieee80211_chan2ieee(ic, se->se_chan))) + fail |= MATCH_CHANNEL; + /* + * NB: normally the desired mode is used to construct + * the channel list, but it's possible for the scan + * cache to include entries for stations outside this + * list so we check the desired mode here to weed them + * out. + */ + if (vap->iv_des_mode != IEEE80211_MODE_AUTO && + (se->se_chan->ic_flags & IEEE80211_CHAN_ALLTURBO) != + chanflags[vap->iv_des_mode]) + fail |= MATCH_CHANNEL; + if (vap->iv_opmode == IEEE80211_M_IBSS) { + if ((se->se_capinfo & IEEE80211_CAPINFO_IBSS) == 0) + fail |= MATCH_CAPINFO; +#ifdef IEEE80211_SUPPORT_TDMA + } else if (vap->iv_opmode == IEEE80211_M_AHDEMO) { + /* + * Adhoc demo network setup shouldn't really be scanning + * but just in case skip stations operating in IBSS or + * BSS mode. + */ + if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) + fail |= MATCH_CAPINFO; + /* + * TDMA operation cannot coexist with a normal 802.11 network; + * skip if IBSS or ESS capabilities are marked and require + * the beacon have a TDMA ie present. + */ + if (vap->iv_caps & IEEE80211_C_TDMA) { + const struct ieee80211_tdma_param *tdma = + (const struct ieee80211_tdma_param *)se->se_ies.tdma_ie; + const struct ieee80211_tdma_state *ts = vap->iv_tdma; + + if (tdma == NULL) + fail |= MATCH_TDMA_NOIE; + else if (tdma->tdma_version != ts->tdma_version) + fail |= MATCH_TDMA_VERSION; + else if (tdma->tdma_slot != 0) + fail |= MATCH_TDMA_NOTMASTER; + else if (tdma_isfull(tdma)) + fail |= MATCH_TDMA_NOSLOT; +#if 0 + else if (ieee80211_local_address(se->se_macaddr)) + fail |= MATCH_TDMA_LOCAL; +#endif + } +#endif /* IEEE80211_SUPPORT_TDMA */ +#ifdef IEEE80211_SUPPORT_MESH + } else if (vap->iv_opmode == IEEE80211_M_MBSS) { + const struct ieee80211_mesh_state *ms = vap->iv_mesh; + /* + * Mesh nodes have IBSS & ESS bits in capinfo turned off + * and two special ie's that must be present. + */ + if (se->se_capinfo & (IEEE80211_CAPINFO_IBSS|IEEE80211_CAPINFO_ESS)) + fail |= MATCH_CAPINFO; + else if (se->se_meshid[0] != IEEE80211_ELEMID_MESHID) + fail |= MATCH_MESH_NOID; + else if (ms->ms_idlen != 0 && + match_id(se->se_meshid, ms->ms_id, ms->ms_idlen)) + fail |= MATCH_MESHID; +#endif + } else { + if ((se->se_capinfo & IEEE80211_CAPINFO_ESS) == 0) + fail |= MATCH_CAPINFO; + /* + * If 11d is enabled and we're attempting to join a bss + * that advertises it's country code then compare our + * current settings to what we fetched from the country ie. + * If our country code is unspecified or different then do + * not attempt to join the bss. We should have already + * dispatched an event to user space that identifies the + * new country code so our regdomain config should match. + */ + if ((IEEE80211_IS_CHAN_11D(se->se_chan) || + (vap->iv_flags_ext & IEEE80211_FEXT_DOTD)) && + se->se_cc[0] != 0 && + (ic->ic_regdomain.country == CTRY_DEFAULT || + !isocmp(se->se_cc, ic->ic_regdomain.isocc))) + fail |= MATCH_CC; + } + if (vap->iv_flags & IEEE80211_F_PRIVACY) { + if ((se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) == 0) + fail |= MATCH_PRIVACY; + } else { + /* XXX does this mean privacy is supported or required? */ + if (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) + fail |= MATCH_PRIVACY; + } + se0->se_flags &= ~STA_DEMOTE11B; + rate = check_rate(vap, se->se_chan, se); + if (rate & IEEE80211_RATE_BASIC) { + fail |= MATCH_RATE; + /* + * An 11b-only ap will give a rate mismatch if there is an + * OFDM fixed tx rate for 11g. Try downgrading the channel + * in the scan list to 11b and retry the rate check. + */ + if (IEEE80211_IS_CHAN_ANYG(se->se_chan)) { + rate = check_rate(vap, demote11b(vap, se->se_chan), se); + if ((rate & IEEE80211_RATE_BASIC) == 0) { + fail &= ~MATCH_RATE; + se0->se_flags |= STA_DEMOTE11B; + } + } + } else if (rate < 2*24) { + /* + * This is an 11b-only ap. Check the desired mode in + * case that needs to be honored (mode 11g filters out + * 11b-only ap's). Otherwise force any 11g channel used + * in scanning to be demoted. + * + * NB: we cheat a bit here by looking at the max rate; + * we could/should check the rates. + */ + if (!(vap->iv_des_mode == IEEE80211_MODE_AUTO || + vap->iv_des_mode == IEEE80211_MODE_11B)) + fail |= MATCH_RATE; + else + se0->se_flags |= STA_DEMOTE11B; + } + if (ss->ss_nssid != 0 && + !match_ssid(se->se_ssid, ss->ss_nssid, ss->ss_ssid)) + fail |= MATCH_SSID; + if ((vap->iv_flags & IEEE80211_F_DESBSSID) && + !IEEE80211_ADDR_EQ(vap->iv_des_bssid, se->se_bssid)) + fail |= MATCH_BSSID; + if (se0->se_fails >= STA_FAILS_MAX) + fail |= MATCH_FAILS; + if (se0->se_notseen >= STA_PURGE_SCANS) + fail |= MATCH_NOTSEEN; + if (se->se_rssi < STA_RSSI_MIN) + fail |= MATCH_RSSI; +#ifdef IEEE80211_DEBUG + if (ieee80211_msg(vap, debug)) { + printf(" %c %s", + fail & MATCH_FAILS ? '=' : + fail & MATCH_NOTSEEN ? '^' : + fail & MATCH_CC ? '$' : +#ifdef IEEE80211_SUPPORT_TDMA + fail & MATCH_TDMA_NOIE ? '&' : + fail & MATCH_TDMA_VERSION ? 'v' : + fail & MATCH_TDMA_NOTMASTER ? 's' : + fail & MATCH_TDMA_NOSLOT ? 'f' : + fail & MATCH_TDMA_LOCAL ? 'l' : +#endif + fail & MATCH_MESH_NOID ? 'm' : + fail ? '-' : '+', ether_sprintf(se->se_macaddr)); + printf(" %s%c", ether_sprintf(se->se_bssid), + fail & MATCH_BSSID ? '!' : ' '); + printf(" %3d%c", ieee80211_chan2ieee(ic, se->se_chan), + fail & MATCH_CHANNEL ? '!' : ' '); + printf(" %+4d%c", se->se_rssi, fail & MATCH_RSSI ? '!' : ' '); + printf(" %2dM%c", (rate & IEEE80211_RATE_VAL) / 2, + fail & MATCH_RATE ? '!' : ' '); + printf(" %4s%c", + (se->se_capinfo & IEEE80211_CAPINFO_ESS) ? "ess" : + (se->se_capinfo & IEEE80211_CAPINFO_IBSS) ? "ibss" : "", + fail & MATCH_CAPINFO ? '!' : ' '); + printf(" %3s%c ", + (se->se_capinfo & IEEE80211_CAPINFO_PRIVACY) ? + "wep" : "no", + fail & MATCH_PRIVACY ? '!' : ' '); + ieee80211_print_essid(se->se_ssid+2, se->se_ssid[1]); + printf("%s\n", fail & (MATCH_SSID | MATCH_MESHID) ? "!" : ""); + } +#endif + return fail; +} + +static void +sta_update_notseen(struct sta_table *st) +{ + struct sta_entry *se; + + IEEE80211_SCAN_TABLE_LOCK(st); + TAILQ_FOREACH(se, &st->st_entry, se_list) { + /* + * If seen the reset and don't bump the count; + * otherwise bump the ``not seen'' count. Note + * that this insures that stations for which we + * see frames while not scanning but not during + * this scan will not be penalized. + */ + if (se->se_seen) + se->se_seen = 0; + else + se->se_notseen++; + } + IEEE80211_SCAN_TABLE_UNLOCK(st); +} + +static void +sta_dec_fails(struct sta_table *st) +{ + struct sta_entry *se; + + IEEE80211_SCAN_TABLE_LOCK(st); + TAILQ_FOREACH(se, &st->st_entry, se_list) + if (se->se_fails) + se->se_fails--; + IEEE80211_SCAN_TABLE_UNLOCK(st); +} + +static struct sta_entry * +select_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap, int debug) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se, *selbs = NULL; + + IEEE80211_DPRINTF(vap, debug, " %s\n", + "macaddr bssid chan rssi rate flag wep essid"); + IEEE80211_SCAN_TABLE_LOCK(st); + TAILQ_FOREACH(se, &st->st_entry, se_list) { + ieee80211_ies_expand(&se->base.se_ies); + if (match_bss(vap, ss, se, debug) == 0) { + if (selbs == NULL) + selbs = se; + else if (sta_compare(se, selbs) > 0) + selbs = se; + } + } + IEEE80211_SCAN_TABLE_UNLOCK(st); + + return selbs; +} + +/* + * Pick an ap or ibss network to join or find a channel + * to use to start an ibss network. + */ +static int +sta_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *selbs; + struct ieee80211_channel *chan; + + KASSERT(vap->iv_opmode == IEEE80211_M_STA, + ("wrong mode %u", vap->iv_opmode)); + + if (st->st_newscan) { + sta_update_notseen(st); + st->st_newscan = 0; + } + if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { + /* + * Manual/background scan, don't select+join the + * bss, just return. The scanning framework will + * handle notification that this has completed. + */ + ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; + return 1; + } + /* + * Automatic sequencing; look for a candidate and + * if found join the network. + */ + /* NB: unlocked read should be ok */ + if (TAILQ_FIRST(&st->st_entry) == NULL) { + IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, + "%s: no scan candidate\n", __func__); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return 0; +notfound: + /* + * If nothing suitable was found decrement + * the failure counts so entries will be + * reconsidered the next time around. We + * really want to do this only for sta's + * where we've previously had some success. + */ + sta_dec_fails(st); + st->st_newscan = 1; + return 0; /* restart scan */ + } + selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return (selbs != NULL); + if (selbs == NULL) + goto notfound; + chan = selbs->base.se_chan; + if (selbs->se_flags & STA_DEMOTE11B) + chan = demote11b(vap, chan); + if (!ieee80211_sta_join(vap, chan, &selbs->base)) + goto notfound; + return 1; /* terminate scan */ +} + +/* + * Lookup an entry in the scan cache. We assume we're + * called from the bottom half or such that we don't need + * to block the bottom half so that it's safe to return + * a reference to an entry w/o holding the lock on the table. + */ +static struct sta_entry * +sta_lookup(struct sta_table *st, const uint8_t macaddr[IEEE80211_ADDR_LEN]) +{ + struct sta_entry *se; + int hash = STA_HASH(macaddr); + + IEEE80211_SCAN_TABLE_LOCK(st); + LIST_FOREACH(se, &st->st_hash[hash], se_hash) + if (IEEE80211_ADDR_EQ(se->base.se_macaddr, macaddr)) + break; + IEEE80211_SCAN_TABLE_UNLOCK(st); + + return se; /* NB: unlocked */ +} + +static void +sta_roam_check(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct ieee80211com *ic = vap->iv_ic; + struct ieee80211_node *ni = vap->iv_bss; + struct sta_table *st = ss->ss_priv; + enum ieee80211_phymode mode; + struct sta_entry *se, *selbs; + uint8_t roamRate, curRate, ucastRate; + int8_t roamRssi, curRssi; + + se = sta_lookup(st, ni->ni_macaddr); + if (se == NULL) { + /* XXX something is wrong */ + return; + } + + mode = ieee80211_chan2mode(ic->ic_bsschan); + roamRate = vap->iv_roamparms[mode].rate; + roamRssi = vap->iv_roamparms[mode].rssi; + ucastRate = vap->iv_txparms[mode].ucastrate; + /* NB: the most up to date rssi is in the node, not the scan cache */ + curRssi = ic->ic_node_getrssi(ni); + if (ucastRate == IEEE80211_FIXED_RATE_NONE) { + curRate = ni->ni_txrate; + roamRate &= IEEE80211_RATE_VAL; + IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, + "%s: currssi %d currate %u roamrssi %d roamrate %u\n", + __func__, curRssi, curRate, roamRssi, roamRate); + } else { + curRate = roamRate; /* NB: insure compare below fails */ + IEEE80211_DPRINTF(vap, IEEE80211_MSG_ROAM, + "%s: currssi %d roamrssi %d\n", __func__, curRssi, roamRssi); + } + /* + * Check if a new ap should be used and switch. + * XXX deauth current ap + */ + if (curRate < roamRate || curRssi < roamRssi) { + if (time_after(ticks, ic->ic_lastscan + vap->iv_scanvalid)) { + /* + * Scan cache contents are too old; force a scan now + * if possible so we have current state to make a + * decision with. We don't kick off a bg scan if + * we're using dynamic turbo and boosted or if the + * channel is busy. + * XXX force immediate switch on scan complete + */ + if (!IEEE80211_IS_CHAN_DTURBO(ic->ic_curchan) && + time_after(ticks, ic->ic_lastdata + vap->iv_bgscanidle)) + ieee80211_bg_scan(vap, 0); + return; + } + se->base.se_rssi = curRssi; + selbs = select_bss(ss, vap, IEEE80211_MSG_ROAM); + if (selbs != NULL && selbs != se) { + struct ieee80211_channel *chan; + + IEEE80211_DPRINTF(vap, + IEEE80211_MSG_ROAM | IEEE80211_MSG_DEBUG, + "%s: ROAM: curRate %u, roamRate %u, " + "curRssi %d, roamRssi %d\n", __func__, + curRate, roamRate, curRssi, roamRssi); + + chan = selbs->base.se_chan; + if (selbs->se_flags & STA_DEMOTE11B) + chan = demote11b(vap, chan); + (void) ieee80211_sta_join(vap, chan, &selbs->base); + } + } +} + +/* + * Age entries in the scan cache. + * XXX also do roaming since it's convenient + */ +static void +sta_age(struct ieee80211_scan_state *ss) +{ + struct ieee80211vap *vap = ss->ss_vap; + + adhoc_age(ss); + /* + * If rate control is enabled check periodically to see if + * we should roam from our current connection to one that + * might be better. This only applies when we're operating + * in sta mode and automatic roaming is set. + * XXX defer if busy + * XXX repeater station + * XXX do when !bgscan? + */ + KASSERT(vap->iv_opmode == IEEE80211_M_STA, + ("wrong mode %u", vap->iv_opmode)); + if (vap->iv_roaming == IEEE80211_ROAMING_AUTO && + (vap->iv_flags & IEEE80211_F_BGSCAN) && + vap->iv_state >= IEEE80211_S_RUN) + /* XXX vap is implicit */ + sta_roam_check(ss, vap); +} + +/* + * Iterate over the entries in the scan cache, invoking + * the callback function on each one. + */ +static void +sta_iterate(struct ieee80211_scan_state *ss, + ieee80211_scan_iter_func *f, void *arg) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se; + u_int gen; + + mtx_lock(&st->st_scanlock); + gen = st->st_scaniter++; +restart: + IEEE80211_SCAN_TABLE_LOCK(st); + TAILQ_FOREACH(se, &st->st_entry, se_list) { + if (se->se_scangen != gen) { + se->se_scangen = gen; + /* update public state */ + se->base.se_age = ticks - se->se_lastupdate; + IEEE80211_SCAN_TABLE_UNLOCK(st); + (*f)(arg, &se->base); + goto restart; + } + } + IEEE80211_SCAN_TABLE_UNLOCK(st); + + mtx_unlock(&st->st_scanlock); +} + +static void +sta_assoc_fail(struct ieee80211_scan_state *ss, + const uint8_t macaddr[IEEE80211_ADDR_LEN], int reason) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se; + + se = sta_lookup(st, macaddr); + if (se != NULL) { + se->se_fails++; + se->se_lastfail = ticks; + IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, + macaddr, "%s: reason %u fails %u", + __func__, reason, se->se_fails); + } +} + +static void +sta_assoc_success(struct ieee80211_scan_state *ss, + const uint8_t macaddr[IEEE80211_ADDR_LEN]) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se; + + se = sta_lookup(st, macaddr); + if (se != NULL) { +#if 0 + se->se_fails = 0; + IEEE80211_NOTE_MAC(ss->ss_vap, IEEE80211_MSG_SCAN, + macaddr, "%s: fails %u", + __func__, se->se_fails); +#endif + se->se_lastassoc = ticks; + } +} + +static const struct ieee80211_scanner sta_default = { + .scan_name = "default", + .scan_attach = sta_attach, + .scan_detach = sta_detach, + .scan_start = sta_start, + .scan_restart = sta_restart, + .scan_cancel = sta_cancel, + .scan_end = sta_pick_bss, + .scan_flush = sta_flush, + .scan_add = sta_add, + .scan_age = sta_age, + .scan_iterate = sta_iterate, + .scan_assoc_fail = sta_assoc_fail, + .scan_assoc_success = sta_assoc_success, +}; +IEEE80211_SCANNER_ALG(sta, IEEE80211_M_STA, sta_default); + +/* + * Adhoc mode-specific support. + */ + +static const uint16_t adhocWorld[] = /* 36, 40, 44, 48 */ +{ 5180, 5200, 5220, 5240 }; +static const uint16_t adhocFcc3[] = /* 36, 40, 44, 48 145, 149, 153, 157, 161, 165 */ +{ 5180, 5200, 5220, 5240, 5725, 5745, 5765, 5785, 5805, 5825 }; +static const uint16_t adhocMkk[] = /* 34, 38, 42, 46 */ +{ 5170, 5190, 5210, 5230 }; +static const uint16_t adhoc11b[] = /* 10, 11 */ +{ 2457, 2462 }; + +static const struct scanlist adhocScanTable[] = { + { IEEE80211_MODE_11B, X(adhoc11b) }, + { IEEE80211_MODE_11A, X(adhocWorld) }, + { IEEE80211_MODE_11A, X(adhocFcc3) }, + { IEEE80211_MODE_11B, X(adhocMkk) }, + { .list = NULL } +}; +#undef X + +/* + * Start an adhoc-mode scan by populating the channel list. + */ +static int +adhoc_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + + makescanlist(ss, vap, adhocScanTable); + + if (ss->ss_mindwell == 0) + ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ + if (ss->ss_maxdwell == 0) + ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ + + st->st_scangen++; + st->st_newscan = 1; + + return 0; +} + +/* + * Select a channel to start an adhoc network on. + * The channel list was populated with appropriate + * channels so select one that looks least occupied. + */ +static struct ieee80211_channel * +adhoc_pick_channel(struct ieee80211_scan_state *ss, int flags) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se; + struct ieee80211_channel *c, *bestchan; + int i, bestrssi, maxrssi; + + bestchan = NULL; + bestrssi = -1; + + IEEE80211_SCAN_TABLE_LOCK(st); + for (i = 0; i < ss->ss_last; i++) { + c = ss->ss_chans[i]; + /* never consider a channel with radar */ + if (IEEE80211_IS_CHAN_RADAR(c)) + continue; + /* skip channels disallowed by regulatory settings */ + if (IEEE80211_IS_CHAN_NOADHOC(c)) + continue; + /* check channel attributes for band compatibility */ + if (flags != 0 && (c->ic_flags & flags) != flags) + continue; + maxrssi = 0; + TAILQ_FOREACH(se, &st->st_entry, se_list) { + if (se->base.se_chan != c) + continue; + if (se->base.se_rssi > maxrssi) + maxrssi = se->base.se_rssi; + } + if (bestchan == NULL || maxrssi < bestrssi) + bestchan = c; + } + IEEE80211_SCAN_TABLE_UNLOCK(st); + + return bestchan; +} + +/* + * Pick an ibss network to join or find a channel + * to use to start an ibss network. + */ +static int +adhoc_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *selbs; + struct ieee80211_channel *chan; + + KASSERT(vap->iv_opmode == IEEE80211_M_IBSS || + vap->iv_opmode == IEEE80211_M_AHDEMO || + vap->iv_opmode == IEEE80211_M_MBSS, + ("wrong opmode %u", vap->iv_opmode)); + + if (st->st_newscan) { + sta_update_notseen(st); + st->st_newscan = 0; + } + if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { + /* + * Manual/background scan, don't select+join the + * bss, just return. The scanning framework will + * handle notification that this has completed. + */ + ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; + return 1; + } + /* + * Automatic sequencing; look for a candidate and + * if found join the network. + */ + /* NB: unlocked read should be ok */ + if (TAILQ_FIRST(&st->st_entry) == NULL) { + IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, + "%s: no scan candidate\n", __func__); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return 0; +notfound: + /* NB: never auto-start a tdma network for slot !0 */ +#ifdef IEEE80211_SUPPORT_TDMA + if (vap->iv_des_nssid && + ((vap->iv_caps & IEEE80211_C_TDMA) == 0 || + ieee80211_tdma_getslot(vap) == 0)) { +#else + if (vap->iv_des_nssid) { +#endif + /* + * No existing adhoc network to join and we have + * an ssid; start one up. If no channel was + * specified, try to select a channel. + */ + if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || + IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { + struct ieee80211com *ic = vap->iv_ic; + + chan = adhoc_pick_channel(ss, 0); + if (chan != NULL) + chan = ieee80211_ht_adjust_channel(ic, + chan, vap->iv_flags_ht); + } else + chan = vap->iv_des_chan; + if (chan != NULL) { + ieee80211_create_ibss(vap, chan); + return 1; + } + } + /* + * If nothing suitable was found decrement + * the failure counts so entries will be + * reconsidered the next time around. We + * really want to do this only for sta's + * where we've previously had some success. + */ + sta_dec_fails(st); + st->st_newscan = 1; + return 0; /* restart scan */ + } + selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return (selbs != NULL); + if (selbs == NULL) + goto notfound; + chan = selbs->base.se_chan; + if (selbs->se_flags & STA_DEMOTE11B) + chan = demote11b(vap, chan); + if (!ieee80211_sta_join(vap, chan, &selbs->base)) + goto notfound; + return 1; /* terminate scan */ +} + +/* + * Age entries in the scan cache. + */ +static void +adhoc_age(struct ieee80211_scan_state *ss) +{ + struct sta_table *st = ss->ss_priv; + struct sta_entry *se, *next; + + IEEE80211_SCAN_TABLE_LOCK(st); + TAILQ_FOREACH_SAFE(se, &st->st_entry, se_list, next) { + if (se->se_notseen > STA_PURGE_SCANS) { + TAILQ_REMOVE(&st->st_entry, se, se_list); + LIST_REMOVE(se, se_hash); + ieee80211_ies_cleanup(&se->base.se_ies); + free(se, M_80211_SCAN); + } + } + IEEE80211_SCAN_TABLE_UNLOCK(st); +} + +static const struct ieee80211_scanner adhoc_default = { + .scan_name = "default", + .scan_attach = sta_attach, + .scan_detach = sta_detach, + .scan_start = adhoc_start, + .scan_restart = sta_restart, + .scan_cancel = sta_cancel, + .scan_end = adhoc_pick_bss, + .scan_flush = sta_flush, + .scan_pickchan = adhoc_pick_channel, + .scan_add = sta_add, + .scan_age = adhoc_age, + .scan_iterate = sta_iterate, + .scan_assoc_fail = sta_assoc_fail, + .scan_assoc_success = sta_assoc_success, +}; +IEEE80211_SCANNER_ALG(ibss, IEEE80211_M_IBSS, adhoc_default); +IEEE80211_SCANNER_ALG(ahdemo, IEEE80211_M_AHDEMO, adhoc_default); + +static void +ap_force_promisc(struct ieee80211com *ic) +{ + struct ifnet *ifp = ic->ic_ifp; + + IEEE80211_LOCK(ic); + /* set interface into promiscuous mode */ + ifp->if_flags |= IFF_PROMISC; + ieee80211_runtask(ic, &ic->ic_promisc_task); + IEEE80211_UNLOCK(ic); +} + +static void +ap_reset_promisc(struct ieee80211com *ic) +{ + IEEE80211_LOCK(ic); + ieee80211_syncifflag_locked(ic, IFF_PROMISC); + IEEE80211_UNLOCK(ic); +} + +static int +ap_start(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + + makescanlist(ss, vap, staScanTable); + + if (ss->ss_mindwell == 0) + ss->ss_mindwell = msecs_to_ticks(200); /* 200ms */ + if (ss->ss_maxdwell == 0) + ss->ss_maxdwell = msecs_to_ticks(200); /* 200ms */ + + st->st_scangen++; + st->st_newscan = 1; + + ap_force_promisc(vap->iv_ic); + return 0; +} + +/* + * Cancel an ongoing scan. + */ +static int +ap_cancel(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + ap_reset_promisc(vap->iv_ic); + return 0; +} + +/* + * Pick a quiet channel to use for ap operation. + */ +static struct ieee80211_channel * +ap_pick_channel(struct ieee80211_scan_state *ss, int flags) +{ + struct sta_table *st = ss->ss_priv; + struct ieee80211_channel *bestchan = NULL; + int i; + + /* XXX select channel more intelligently, e.g. channel spread, power */ + /* NB: use scan list order to preserve channel preference */ + for (i = 0; i < ss->ss_last; i++) { + struct ieee80211_channel *chan = ss->ss_chans[i]; + /* + * If the channel is unoccupied the max rssi + * should be zero; just take it. Otherwise + * track the channel with the lowest rssi and + * use that when all channels appear occupied. + */ + if (IEEE80211_IS_CHAN_RADAR(chan)) + continue; + if (IEEE80211_IS_CHAN_NOHOSTAP(chan)) + continue; + /* check channel attributes for band compatibility */ + if (flags != 0 && (chan->ic_flags & flags) != flags) + continue; + KASSERT(sizeof(chan->ic_ieee) == 1, ("ic_chan size")); + /* XXX channel have interference */ + if (st->st_maxrssi[chan->ic_ieee] == 0) { + /* XXX use other considerations */ + return chan; + } + if (bestchan == NULL || + st->st_maxrssi[chan->ic_ieee] < st->st_maxrssi[bestchan->ic_ieee]) + bestchan = chan; + } + return bestchan; +} + +/* + * Pick a quiet channel to use for ap operation. + */ +static int +ap_end(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct ieee80211com *ic = vap->iv_ic; + struct ieee80211_channel *bestchan; + + KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP, + ("wrong opmode %u", vap->iv_opmode)); + bestchan = ap_pick_channel(ss, 0); + if (bestchan == NULL) { + /* no suitable channel, should not happen */ + IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, + "%s: no suitable channel! (should not happen)\n", __func__); + /* XXX print something? */ + return 0; /* restart scan */ + } + /* + * If this is a dynamic turbo channel, start with the unboosted one. + */ + if (IEEE80211_IS_CHAN_TURBO(bestchan)) { + bestchan = ieee80211_find_channel(ic, bestchan->ic_freq, + bestchan->ic_flags & ~IEEE80211_CHAN_TURBO); + if (bestchan == NULL) { + /* should never happen ?? */ + return 0; + } + } + ap_reset_promisc(ic); + if (ss->ss_flags & (IEEE80211_SCAN_NOPICK | IEEE80211_SCAN_NOJOIN)) { + /* + * Manual/background scan, don't select+join the + * bss, just return. The scanning framework will + * handle notification that this has completed. + */ + ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; + return 1; + } + ieee80211_create_ibss(vap, + ieee80211_ht_adjust_channel(ic, bestchan, vap->iv_flags_ht)); + return 1; +} + +static const struct ieee80211_scanner ap_default = { + .scan_name = "default", + .scan_attach = sta_attach, + .scan_detach = sta_detach, + .scan_start = ap_start, + .scan_restart = sta_restart, + .scan_cancel = ap_cancel, + .scan_end = ap_end, + .scan_flush = sta_flush, + .scan_pickchan = ap_pick_channel, + .scan_add = sta_add, + .scan_age = adhoc_age, + .scan_iterate = sta_iterate, + .scan_assoc_success = sta_assoc_success, + .scan_assoc_fail = sta_assoc_fail, +}; +IEEE80211_SCANNER_ALG(ap, IEEE80211_M_HOSTAP, ap_default); + +#ifdef IEEE80211_SUPPORT_MESH +/* + * Pick an mbss network to join or find a channel + * to use to start an mbss network. + */ +static int +mesh_pick_bss(struct ieee80211_scan_state *ss, struct ieee80211vap *vap) +{ + struct sta_table *st = ss->ss_priv; + struct ieee80211_mesh_state *ms = vap->iv_mesh; + struct sta_entry *selbs; + struct ieee80211_channel *chan; + + KASSERT(vap->iv_opmode == IEEE80211_M_MBSS, + ("wrong opmode %u", vap->iv_opmode)); + + if (st->st_newscan) { + sta_update_notseen(st); + st->st_newscan = 0; + } + if (ss->ss_flags & IEEE80211_SCAN_NOPICK) { + /* + * Manual/background scan, don't select+join the + * bss, just return. The scanning framework will + * handle notification that this has completed. + */ + ss->ss_flags &= ~IEEE80211_SCAN_NOPICK; + return 1; + } + /* + * Automatic sequencing; look for a candidate and + * if found join the network. + */ + /* NB: unlocked read should be ok */ + if (TAILQ_FIRST(&st->st_entry) == NULL) { + IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, + "%s: no scan candidate\n", __func__); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return 0; +notfound: + if (ms->ms_idlen != 0) { + /* + * No existing mbss network to join and we have + * a meshid; start one up. If no channel was + * specified, try to select a channel. + */ + if (vap->iv_des_chan == IEEE80211_CHAN_ANYC || + IEEE80211_IS_CHAN_RADAR(vap->iv_des_chan)) { + struct ieee80211com *ic = vap->iv_ic; + + chan = adhoc_pick_channel(ss, 0); + if (chan != NULL) + chan = ieee80211_ht_adjust_channel(ic, + chan, vap->iv_flags_ht); + } else + chan = vap->iv_des_chan; + if (chan != NULL) { + ieee80211_create_ibss(vap, chan); + return 1; + } + } + /* + * If nothing suitable was found decrement + * the failure counts so entries will be + * reconsidered the next time around. We + * really want to do this only for sta's + * where we've previously had some success. + */ + sta_dec_fails(st); + st->st_newscan = 1; + return 0; /* restart scan */ + } + selbs = select_bss(ss, vap, IEEE80211_MSG_SCAN); + if (ss->ss_flags & IEEE80211_SCAN_NOJOIN) + return (selbs != NULL); + if (selbs == NULL) + goto notfound; + chan = selbs->base.se_chan; + if (selbs->se_flags & STA_DEMOTE11B) + chan = demote11b(vap, chan); + if (!ieee80211_sta_join(vap, chan, &selbs->base)) + goto notfound; + return 1; /* terminate scan */ +} + +static const struct ieee80211_scanner mesh_default = { + .scan_name = "default", + .scan_attach = sta_attach, + .scan_detach = sta_detach, + .scan_start = adhoc_start, + .scan_restart = sta_restart, + .scan_cancel = sta_cancel, + .scan_end = mesh_pick_bss, + .scan_flush = sta_flush, + .scan_pickchan = adhoc_pick_channel, + .scan_add = sta_add, + .scan_age = adhoc_age, + .scan_iterate = sta_iterate, + .scan_assoc_fail = sta_assoc_fail, + .scan_assoc_success = sta_assoc_success, +}; +IEEE80211_SCANNER_ALG(mesh, IEEE80211_M_MBSS, mesh_default); +#endif /* IEEE80211_SUPPORT_MESH */ |