/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2002-2008 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 <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* IEEE 802.11 scanning support.
*/
#include "opt_wlan.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/condvar.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_media.h>
#include <net/if_private.h>
#include <net/ethernet.h>
#include <net80211/ieee80211_var.h>
/* XXX until it's implemented as attach ops */
#include <net80211/ieee80211_scan_sw.h>
#include <net/bpf.h>
/*
* Roaming-related defaults. RSSI thresholds are as returned by the
* driver (.5dBm). Transmit rate thresholds are IEEE rate codes (i.e
* .5M units) or MCS.
*/
/* rssi thresholds */
#define ROAM_RSSI_11A_DEFAULT 14 /* 11a bss */
#define ROAM_RSSI_11B_DEFAULT 14 /* 11b bss */
#define ROAM_RSSI_11BONLY_DEFAULT 14 /* 11b-only bss */
/* transmit rate thresholds */
#define ROAM_RATE_11A_DEFAULT 2*12 /* 11a bss */
#define ROAM_RATE_11B_DEFAULT 2*5 /* 11b bss */
#define ROAM_RATE_11BONLY_DEFAULT 2*1 /* 11b-only bss */
#define ROAM_RATE_HALF_DEFAULT 2*6 /* half-width 11a/g bss */
#define ROAM_RATE_QUARTER_DEFAULT 2*3 /* quarter-width 11a/g bss */
#define ROAM_MCS_11N_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11n bss */
#define ROAM_MCS_11AC_DEFAULT (1 | IEEE80211_RATE_MCS) /* 11ac bss; XXX not used yet */
void
ieee80211_scan_attach(struct ieee80211com *ic)
{
/*
* If there's no scan method pointer, attach the
* swscan set as a default.
*/
if (ic->ic_scan_methods == NULL)
ieee80211_swscan_attach(ic);
else
ic->ic_scan_methods->sc_attach(ic);
}
void
ieee80211_scan_detach(struct ieee80211com *ic)
{
/*
* Ideally we'd do the ss_ops detach call here;
* but then sc_detach() would need to be split in two.
*
* I'll do that later.
*/
ic->ic_scan_methods->sc_detach(ic);
}
static const struct ieee80211_roamparam defroam[IEEE80211_MODE_MAX] = {
[IEEE80211_MODE_11A] = { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_11A_DEFAULT },
[IEEE80211_MODE_11G] = { .rssi = ROAM_RSSI_11B_DEFAULT,
.rate = ROAM_RATE_11B_DEFAULT },
[IEEE80211_MODE_11B] = { .rssi = ROAM_RSSI_11BONLY_DEFAULT,
.rate = ROAM_RATE_11BONLY_DEFAULT },
[IEEE80211_MODE_TURBO_A]= { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_11A_DEFAULT },
[IEEE80211_MODE_TURBO_G]= { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_11A_DEFAULT },
[IEEE80211_MODE_STURBO_A]={ .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_11A_DEFAULT },
[IEEE80211_MODE_HALF] = { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_HALF_DEFAULT },
[IEEE80211_MODE_QUARTER]= { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_RATE_QUARTER_DEFAULT },
[IEEE80211_MODE_11NA] = { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_MCS_11N_DEFAULT },
[IEEE80211_MODE_11NG] = { .rssi = ROAM_RSSI_11B_DEFAULT,
.rate = ROAM_MCS_11N_DEFAULT },
[IEEE80211_MODE_VHT_2GHZ] = { .rssi = ROAM_RSSI_11B_DEFAULT,
.rate = ROAM_MCS_11AC_DEFAULT },
[IEEE80211_MODE_VHT_5GHZ] = { .rssi = ROAM_RSSI_11A_DEFAULT,
.rate = ROAM_MCS_11AC_DEFAULT },
};
void
ieee80211_scan_vattach(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
int m;
vap->iv_bgscanidle = (IEEE80211_BGSCAN_IDLE_DEFAULT*1000)/hz;
vap->iv_bgscanintvl = IEEE80211_BGSCAN_INTVAL_DEFAULT*hz;
vap->iv_scanvalid = IEEE80211_SCAN_VALID_DEFAULT*hz;
vap->iv_roaming = IEEE80211_ROAMING_AUTO;
memset(vap->iv_roamparms, 0, sizeof(vap->iv_roamparms));
for (m = IEEE80211_MODE_AUTO + 1; m < IEEE80211_MODE_MAX; m++) {
if (isclr(ic->ic_modecaps, m))
continue;
memcpy(&vap->iv_roamparms[m], &defroam[m], sizeof(defroam[m]));
}
ic->ic_scan_methods->sc_vattach(vap);
}
void
ieee80211_scan_vdetach(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
struct ieee80211_scan_state *ss;
IEEE80211_LOCK(ic);
ss = ic->ic_scan;
ic->ic_scan_methods->sc_vdetach(vap);
if (ss != NULL && ss->ss_vap == vap) {
if (ss->ss_ops != NULL) {
ss->ss_ops->scan_detach(ss);
ss->ss_ops = NULL;
}
ss->ss_vap = NULL;
}
IEEE80211_UNLOCK(ic);
}
/*
* Simple-minded scanner module support.
*/
static const char *scan_modnames[IEEE80211_OPMODE_MAX] = {
"wlan_scan_sta", /* IEEE80211_M_IBSS */
"wlan_scan_sta", /* IEEE80211_M_STA */
"wlan_scan_wds", /* IEEE80211_M_WDS */
"wlan_scan_sta", /* IEEE80211_M_AHDEMO */
"wlan_scan_ap", /* IEEE80211_M_HOSTAP */
"wlan_scan_monitor", /* IEEE80211_M_MONITOR */
"wlan_scan_sta", /* IEEE80211_M_MBSS */
};
static const struct ieee80211_scanner *scanners[IEEE80211_OPMODE_MAX];
const struct ieee80211_scanner *
ieee80211_scanner_get(enum ieee80211_opmode mode)
{
if (mode >= IEEE80211_OPMODE_MAX)
return NULL;
if (scanners[mode] == NULL)
ieee80211_load_module(scan_modnames[mode]);
return scanners[mode];
}
void
ieee80211_scanner_register(enum ieee80211_opmode mode,
const struct ieee80211_scanner *scan)
{
if (mode >= IEEE80211_OPMODE_MAX)
return;
scanners[mode] = scan;
}
void
ieee80211_scanner_unregister(enum ieee80211_opmode mode,
const struct ieee80211_scanner *scan)
{
if (mode >= IEEE80211_OPMODE_MAX)
return;
if (scanners[mode] == scan)
scanners[mode] = NULL;
}
void
ieee80211_scanner_unregister_all(const struct ieee80211_scanner *scan)
{
int m;
for (m = 0; m < IEEE80211_OPMODE_MAX; m++)
if (scanners[m] == scan)
scanners[m] = NULL;
}
/*
* Update common scanner state to reflect the current
* operating mode. This is called when the state machine
* is transitioned to RUN state w/o scanning--e.g. when
* operating in monitor mode. The purpose of this is to
* ensure later callbacks find ss_ops set to properly
* reflect current operating mode.
*/
void
ieee80211_scan_update_locked(struct ieee80211vap *vap,
const struct ieee80211_scanner *scan)
{
struct ieee80211com *ic = vap->iv_ic;
struct ieee80211_scan_state *ss = ic->ic_scan;
IEEE80211_LOCK_ASSERT(ic);
#ifdef IEEE80211_DEBUG
if (ss->ss_vap != vap || ss->ss_ops != scan) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: current scanner is <%s:%s>, switch to <%s:%s>\n",
__func__,
ss->ss_vap != NULL ?
ss->ss_vap->iv_ifp->if_xname : "none",
ss->ss_vap != NULL ?
ieee80211_opmode_name[ss->ss_vap->iv_opmode] : "none",
vap->iv_ifp->if_xname,
ieee80211_opmode_name[vap->iv_opmode]);
}
#endif
ss->ss_vap = vap;
if (ss->ss_ops != scan) {
/*
* Switch scanners; detach old, attach new. Special
* case where a single scan module implements multiple
* policies by using different scan ops but a common
* core. We assume if the old and new attach methods
* are identical then it's ok to just change ss_ops
* and not flush the internal state of the module.
*/
if (scan == NULL || ss->ss_ops == NULL ||
ss->ss_ops->scan_attach != scan->scan_attach) {
if (ss->ss_ops != NULL)
ss->ss_ops->scan_detach(ss);
if (scan != NULL && !scan->scan_attach(ss)) {
/* XXX attach failure */
/* XXX stat+msg */
scan = NULL;
}
}
ss->ss_ops = scan;
}
}
#ifdef IEEE80211_DEBUG
static void
ieee80211_scan_dump_channels(const struct ieee80211_scan_state *ss)
{
struct ieee80211com *ic = ss->ss_ic;
const char *sep;
int i;
sep = "";
for (i = ss->ss_next; i < ss->ss_last; i++) {
const struct ieee80211_channel *c = ss->ss_chans[i];
printf("%s%u%c", sep, ieee80211_chan2ieee(ic, c),
ieee80211_channel_type_char(c));
sep = ", ";
}
}
void
ieee80211_scan_dump(struct ieee80211_scan_state *ss)
{
struct ieee80211vap *vap = ss->ss_vap;
if_printf(vap->iv_ifp, "scan set ");
ieee80211_scan_dump_channels(ss);
printf(" dwell min %ums max %ums\n",
ticks_to_msecs(ss->ss_mindwell), ticks_to_msecs(ss->ss_maxdwell));
}
#endif /* IEEE80211_DEBUG */
void
ieee80211_scan_copy_ssid(struct ieee80211vap *vap, struct ieee80211_scan_state *ss,
int nssid, const struct ieee80211_scan_ssid ssids[])
{
if (nssid > IEEE80211_SCAN_MAX_SSID) {
/* XXX printf */
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: too many ssid %d, ignoring all of them\n",
__func__, nssid);
return;
}
memcpy(ss->ss_ssid, ssids, nssid * sizeof(ssids[0]));
ss->ss_nssid = nssid;
}
/*
* Start a scan unless one is already going.
*/
int
ieee80211_start_scan(struct ieee80211vap *vap, int flags,
u_int duration, u_int mindwell, u_int maxdwell,
u_int nssid, const struct ieee80211_scan_ssid ssids[])
{
const struct ieee80211_scanner *scan;
struct ieee80211com *ic = vap->iv_ic;
scan = ieee80211_scanner_get(vap->iv_opmode);
if (scan == NULL) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: no scanner support for %s mode\n",
__func__, ieee80211_opmode_name[vap->iv_opmode]);
/* XXX stat */
return 0;
}
return ic->ic_scan_methods->sc_start_scan(scan, vap, flags, duration,
mindwell, maxdwell, nssid, ssids);
}
/*
* Check the scan cache for an ap/channel to use; if that
* fails then kick off a new scan.
*/
int
ieee80211_check_scan(struct ieee80211vap *vap, int flags,
u_int duration, u_int mindwell, u_int maxdwell,
u_int nssid, const struct ieee80211_scan_ssid ssids[])
{
struct ieee80211com *ic = vap->iv_ic;
struct ieee80211_scan_state *ss = ic->ic_scan;
const struct ieee80211_scanner *scan;
int result;
scan = ieee80211_scanner_get(vap->iv_opmode);
if (scan == NULL) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: no scanner support for %s mode\n",
__func__, vap->iv_opmode);
/* XXX stat */
return 0;
}
/*
* Check if there's a list of scan candidates already.
* XXX want more than the ap we're currently associated with
*/
IEEE80211_LOCK(ic);
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: %s scan, %s%s%s%s%s\n"
, __func__
, flags & IEEE80211_SCAN_ACTIVE ? "active" : "passive"
, flags & IEEE80211_SCAN_FLUSH ? "flush" : "append"
, flags & IEEE80211_SCAN_NOPICK ? ", nopick" : ""
, flags & IEEE80211_SCAN_NOJOIN ? ", nojoin" : ""
, flags & IEEE80211_SCAN_PICK1ST ? ", pick1st" : ""
, flags & IEEE80211_SCAN_ONCE ? ", once" : ""
);
if (ss->ss_ops != scan) {
/* XXX re-use cache contents? e.g. adhoc<->sta */
flags |= IEEE80211_SCAN_FLUSH;
}
/*
* XXX TODO: separate things out a bit better.
*/
ieee80211_scan_update_locked(vap, scan);
result = ic->ic_scan_methods->sc_check_scan(scan, vap, flags, duration,
mindwell, maxdwell, nssid, ssids);
IEEE80211_UNLOCK(ic);
return (result);
}
/*
* Check the scan cache for an ap/channel to use; if that fails
* then kick off a scan using the current settings.
*/
int
ieee80211_check_scan_current(struct ieee80211vap *vap)
{
return ieee80211_check_scan(vap,
IEEE80211_SCAN_ACTIVE,
IEEE80211_SCAN_FOREVER, 0, 0,
vap->iv_des_nssid, vap->iv_des_ssid);
}
/*
* Restart a previous scan. If the previous scan completed
* then we start again using the existing channel list.
*/
int
ieee80211_bg_scan(struct ieee80211vap *vap, int flags)
{
struct ieee80211com *ic = vap->iv_ic;
const struct ieee80211_scanner *scan;
// IEEE80211_UNLOCK_ASSERT(sc);
scan = ieee80211_scanner_get(vap->iv_opmode);
if (scan == NULL) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN,
"%s: no scanner support for %s mode\n",
__func__, vap->iv_opmode);
/* XXX stat */
return 0;
}
/*
* XXX TODO: pull apart the bgscan logic into whatever
* belongs here and whatever belongs in the software
* scanner.
*/
return (ic->ic_scan_methods->sc_bg_scan(scan, vap, flags));
}
/*
* Cancel any scan currently going on for the specified vap.
*/
void
ieee80211_cancel_scan(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
ic->ic_scan_methods->sc_cancel_scan(vap);
}
/*
* Cancel any scan currently going on.
*
* This is called during normal 802.11 data path to cancel
* a scan so a newly arrived normal data packet can be sent.
*/
void
ieee80211_cancel_anyscan(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
ic->ic_scan_methods->sc_cancel_anyscan(vap);
}
/*
* Manually switch to the next channel in the channel list.
* Provided for drivers that manage scanning themselves
* (e.g. for firmware-based devices).
*/
void
ieee80211_scan_next(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
ic->ic_scan_methods->sc_scan_next(vap);
}
/*
* Manually stop a scan that is currently running.
* Provided for drivers that are not able to scan single channels
* (e.g. for firmware-based devices).
*/
void
ieee80211_scan_done(struct ieee80211vap *vap)
{
struct ieee80211com *ic = vap->iv_ic;
struct ieee80211_scan_state *ss;
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s: called\n", __func__);
IEEE80211_LOCK(ic);
ss = ic->ic_scan;
ss->ss_next = ss->ss_last; /* all channels are complete */
ic->ic_scan_methods->sc_scan_done(vap);
IEEE80211_UNLOCK(ic);
}
/*
* Probe the current channel, if allowed, while scanning.
* If the channel is not marked passive-only then send
* a probe request immediately. Otherwise mark state and
* listen for beacons on the channel; if we receive something
* then we'll transmit a probe request.
*/
void
ieee80211_probe_curchan(struct ieee80211vap *vap, int force)
{
struct ieee80211com *ic = vap->iv_ic;
if ((ic->ic_curchan->ic_flags & IEEE80211_CHAN_PASSIVE) && !force) {
ic->ic_flags_ext |= IEEE80211_FEXT_PROBECHAN;
return;
}
ic->ic_scan_methods->sc_scan_probe_curchan(vap, force);
}
#ifdef IEEE80211_DEBUG
static void
dump_country(const uint8_t *ie)
{
const struct ieee80211_country_ie *cie =
(const struct ieee80211_country_ie *) ie;
int i, nbands, schan, nchan;
if (cie->len < 3) {
printf(" <bogus country ie, len %d>", cie->len);
return;
}
printf(" country [%c%c%c", cie->cc[0], cie->cc[1], cie->cc[2]);
nbands = (cie->len - 3) / sizeof(cie->band[0]);
for (i = 0; i < nbands; i++) {
schan = cie->band[i].schan;
nchan = cie->band[i].nchan;
if (nchan != 1)
printf(" %u-%u,%u", schan, schan + nchan-1,
cie->band[i].maxtxpwr);
else
printf(" %u,%u", schan, cie->band[i].maxtxpwr);
}
printf("]");
}
void
ieee80211_scan_dump_probe_beacon(uint8_t subtype, int isnew,
const uint8_t mac[IEEE80211_ADDR_LEN],
const struct ieee80211_scanparams *sp, int rssi)
{
printf("[%s] %s%s on chan %u (bss chan %u) ",
ether_sprintf(mac), isnew ? "new " : "",
ieee80211_mgt_subtype_name(subtype), sp->chan, sp->bchan);
ieee80211_print_essid(sp->ssid + 2, sp->ssid[1]);
printf(" rssi %d\n", rssi);
if (isnew) {
printf("[%s] caps 0x%x bintval %u erp 0x%x",
ether_sprintf(mac), sp->capinfo, sp->bintval, sp->erp);
if (sp->country != NULL)
dump_country(sp->country);
printf("\n");
}
}
#endif /* IEEE80211_DEBUG */
/*
* Process a beacon or probe response frame.
*/
void
ieee80211_add_scan(struct ieee80211vap *vap,
struct ieee80211_channel *curchan,
const struct ieee80211_scanparams *sp,
const struct ieee80211_frame *wh,
int subtype, int rssi, int noise)
{
struct ieee80211com *ic = vap->iv_ic;
return (ic->ic_scan_methods->sc_add_scan(vap, curchan, sp, wh, subtype,
rssi, noise));
}
/*
* Timeout/age scan cache entries; called from sta timeout
* timer (XXX should be self-contained).
*/
void
ieee80211_scan_timeout(struct ieee80211com *ic)
{
struct ieee80211_scan_state *ss = ic->ic_scan;
if (ss->ss_ops != NULL)
ss->ss_ops->scan_age(ss);
}
/*
* Mark a scan cache entry after a successful associate.
*/
void
ieee80211_scan_assoc_success(struct ieee80211vap *vap,
const uint8_t mac[IEEE80211_ADDR_LEN])
{
struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
if (ss->ss_ops != NULL) {
IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN,
mac, "%s", __func__);
ss->ss_ops->scan_assoc_success(ss, mac);
}
}
/*
* Demerit a scan cache entry after failing to associate.
*/
void
ieee80211_scan_assoc_fail(struct ieee80211vap *vap,
const uint8_t mac[IEEE80211_ADDR_LEN], int reason)
{
struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
if (ss->ss_ops != NULL) {
IEEE80211_NOTE_MAC(vap, IEEE80211_MSG_SCAN, mac,
"%s: reason %u", __func__, reason);
ss->ss_ops->scan_assoc_fail(ss, mac, reason);
}
}
/*
* Iterate over the contents of the scan cache.
*/
void
ieee80211_scan_iterate(struct ieee80211vap *vap,
ieee80211_scan_iter_func *f, void *arg)
{
struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
if (ss->ss_ops != NULL)
ss->ss_ops->scan_iterate(ss, f, arg);
}
/*
* Flush the contents of the scan cache.
*/
void
ieee80211_scan_flush(struct ieee80211vap *vap)
{
struct ieee80211_scan_state *ss = vap->iv_ic->ic_scan;
if (ss->ss_ops != NULL && ss->ss_vap == vap) {
IEEE80211_DPRINTF(vap, IEEE80211_MSG_SCAN, "%s\n", __func__);
ss->ss_ops->scan_flush(ss);
}
}
/*
* Check the scan cache for an ap/channel to use; if that
* fails then kick off a new scan.
*/
struct ieee80211_channel *
ieee80211_scan_pickchannel(struct ieee80211com *ic, int flags)
{
struct ieee80211_scan_state *ss = ic->ic_scan;
IEEE80211_LOCK_ASSERT(ic);
if (ss == NULL || ss->ss_ops == NULL || ss->ss_vap == NULL) {
/* XXX printf? */
return NULL;
}
if (ss->ss_ops->scan_pickchan == NULL) {
IEEE80211_DPRINTF(ss->ss_vap, IEEE80211_MSG_SCAN,
"%s: scan module does not support picking a channel, "
"opmode %s\n", __func__, ss->ss_vap->iv_opmode);
return NULL;
}
return ss->ss_ops->scan_pickchan(ss, flags);
}
