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ibss.c
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ibss.c
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// SPDX-License-Identifier: GPL-2.0-only
/*
* IBSS mode implementation
* Copyright 2003-2008, Jouni Malinen <[email protected]>
* Copyright 2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <[email protected]>
* Copyright 2007, Michael Wu <[email protected]>
* Copyright 2009, Johannes Berg <[email protected]>
* Copyright 2013-2014 Intel Mobile Communications GmbH
* Copyright(c) 2016 Intel Deutschland GmbH
* Copyright(c) 2018-2021 Intel Corporation
*/
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/etherdevice.h>
#include <linux/rtnetlink.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#define IEEE80211_SCAN_INTERVAL (2 * HZ)
#define IEEE80211_IBSS_JOIN_TIMEOUT (7 * HZ)
#define IEEE80211_IBSS_MERGE_INTERVAL (30 * HZ)
#define IEEE80211_IBSS_INACTIVITY_LIMIT (60 * HZ)
#define IEEE80211_IBSS_RSN_INACTIVITY_LIMIT (10 * HZ)
#define IEEE80211_IBSS_MAX_STA_ENTRIES 128
static struct beacon_data *
ieee80211_ibss_build_presp(struct ieee80211_sub_if_data *sdata,
const int beacon_int, const u32 basic_rates,
const u16 capability, u64 tsf,
struct cfg80211_chan_def *chandef,
bool *have_higher_than_11mbit,
struct cfg80211_csa_settings *csa_settings)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int rates_n = 0, i, ri;
struct ieee80211_mgmt *mgmt;
u8 *pos;
struct ieee80211_supported_band *sband;
u32 rate_flags, rates = 0, rates_added = 0;
struct beacon_data *presp;
int frame_len;
int shift;
/* Build IBSS probe response */
frame_len = sizeof(struct ieee80211_hdr_3addr) +
12 /* struct ieee80211_mgmt.u.beacon */ +
2 + IEEE80211_MAX_SSID_LEN /* max SSID */ +
2 + 8 /* max Supported Rates */ +
3 /* max DS params */ +
4 /* IBSS params */ +
5 /* Channel Switch Announcement */ +
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_operation) +
2 + sizeof(struct ieee80211_vht_cap) +
2 + sizeof(struct ieee80211_vht_operation) +
ifibss->ie_len;
presp = kzalloc(sizeof(*presp) + frame_len, GFP_KERNEL);
if (!presp)
return NULL;
presp->head = (void *)(presp + 1);
mgmt = (void *) presp->head;
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_PROBE_RESP);
eth_broadcast_addr(mgmt->da);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
memcpy(mgmt->bssid, ifibss->bssid, ETH_ALEN);
mgmt->u.beacon.beacon_int = cpu_to_le16(beacon_int);
mgmt->u.beacon.timestamp = cpu_to_le64(tsf);
mgmt->u.beacon.capab_info = cpu_to_le16(capability);
pos = (u8 *)mgmt + offsetof(struct ieee80211_mgmt, u.beacon.variable);
*pos++ = WLAN_EID_SSID;
*pos++ = ifibss->ssid_len;
memcpy(pos, ifibss->ssid, ifibss->ssid_len);
pos += ifibss->ssid_len;
sband = local->hw.wiphy->bands[chandef->chan->band];
rate_flags = ieee80211_chandef_rate_flags(chandef);
shift = ieee80211_chandef_get_shift(chandef);
rates_n = 0;
if (have_higher_than_11mbit)
*have_higher_than_11mbit = false;
for (i = 0; i < sband->n_bitrates; i++) {
if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
continue;
if (sband->bitrates[i].bitrate > 110 &&
have_higher_than_11mbit)
*have_higher_than_11mbit = true;
rates |= BIT(i);
rates_n++;
}
*pos++ = WLAN_EID_SUPP_RATES;
*pos++ = min_t(int, 8, rates_n);
for (ri = 0; ri < sband->n_bitrates; ri++) {
int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
5 * (1 << shift));
u8 basic = 0;
if (!(rates & BIT(ri)))
continue;
if (basic_rates & BIT(ri))
basic = 0x80;
*pos++ = basic | (u8) rate;
if (++rates_added == 8) {
ri++; /* continue at next rate for EXT_SUPP_RATES */
break;
}
}
if (sband->band == NL80211_BAND_2GHZ) {
*pos++ = WLAN_EID_DS_PARAMS;
*pos++ = 1;
*pos++ = ieee80211_frequency_to_channel(
chandef->chan->center_freq);
}
*pos++ = WLAN_EID_IBSS_PARAMS;
*pos++ = 2;
/* FIX: set ATIM window based on scan results */
*pos++ = 0;
*pos++ = 0;
if (csa_settings) {
*pos++ = WLAN_EID_CHANNEL_SWITCH;
*pos++ = 3;
*pos++ = csa_settings->block_tx ? 1 : 0;
*pos++ = ieee80211_frequency_to_channel(
csa_settings->chandef.chan->center_freq);
presp->cntdwn_counter_offsets[0] = (pos - presp->head);
*pos++ = csa_settings->count;
presp->cntdwn_current_counter = csa_settings->count;
}
/* put the remaining rates in WLAN_EID_EXT_SUPP_RATES */
if (rates_n > 8) {
*pos++ = WLAN_EID_EXT_SUPP_RATES;
*pos++ = rates_n - 8;
for (; ri < sband->n_bitrates; ri++) {
int rate = DIV_ROUND_UP(sband->bitrates[ri].bitrate,
5 * (1 << shift));
u8 basic = 0;
if (!(rates & BIT(ri)))
continue;
if (basic_rates & BIT(ri))
basic = 0x80;
*pos++ = basic | (u8) rate;
}
}
if (ifibss->ie_len) {
memcpy(pos, ifibss->ie, ifibss->ie_len);
pos += ifibss->ie_len;
}
/* add HT capability and information IEs */
if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT &&
chandef->width != NL80211_CHAN_WIDTH_5 &&
chandef->width != NL80211_CHAN_WIDTH_10 &&
sband->ht_cap.ht_supported) {
struct ieee80211_sta_ht_cap ht_cap;
memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
ieee80211_apply_htcap_overrides(sdata, &ht_cap);
pos = ieee80211_ie_build_ht_cap(pos, &ht_cap, ht_cap.cap);
/*
* Note: According to 802.11n-2009 9.13.3.1, HT Protection
* field and RIFS Mode are reserved in IBSS mode, therefore
* keep them at 0
*/
pos = ieee80211_ie_build_ht_oper(pos, &sband->ht_cap,
chandef, 0, false);
/* add VHT capability and information IEs */
if (chandef->width != NL80211_CHAN_WIDTH_20 &&
chandef->width != NL80211_CHAN_WIDTH_40 &&
sband->vht_cap.vht_supported) {
pos = ieee80211_ie_build_vht_cap(pos, &sband->vht_cap,
sband->vht_cap.cap);
pos = ieee80211_ie_build_vht_oper(pos, &sband->vht_cap,
chandef);
}
}
if (local->hw.queues >= IEEE80211_NUM_ACS)
pos = ieee80211_add_wmm_info_ie(pos, 0); /* U-APSD not in use */
presp->head_len = pos - presp->head;
if (WARN_ON(presp->head_len > frame_len))
goto error;
return presp;
error:
kfree(presp);
return NULL;
}
static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const int beacon_int,
struct cfg80211_chan_def *req_chandef,
const u32 basic_rates,
const u16 capability, u64 tsf,
bool creator)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct ieee80211_mgmt *mgmt;
struct cfg80211_bss *bss;
u32 bss_change;
struct cfg80211_chan_def chandef;
struct ieee80211_channel *chan;
struct beacon_data *presp;
struct cfg80211_inform_bss bss_meta = {};
bool have_higher_than_11mbit;
bool radar_required;
int err;
sdata_assert_lock(sdata);
/* Reset own TSF to allow time synchronization work. */
drv_reset_tsf(local, sdata);
if (!ether_addr_equal(ifibss->bssid, bssid))
sta_info_flush(sdata);
/* if merging, indicate to driver that we leave the old IBSS */
if (sdata->vif.bss_conf.ibss_joined) {
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
netif_carrier_off(sdata->dev);
ieee80211_bss_info_change_notify(sdata,
BSS_CHANGED_IBSS |
BSS_CHANGED_BEACON_ENABLED);
drv_leave_ibss(local, sdata);
}
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
RCU_INIT_POINTER(ifibss->presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
/* make a copy of the chandef, it could be modified below. */
chandef = *req_chandef;
chan = chandef.chan;
if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
NL80211_IFTYPE_ADHOC)) {
if (chandef.width == NL80211_CHAN_WIDTH_5 ||
chandef.width == NL80211_CHAN_WIDTH_10 ||
chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
chandef.width == NL80211_CHAN_WIDTH_20) {
sdata_info(sdata,
"Failed to join IBSS, beacons forbidden\n");
return;
}
chandef.width = NL80211_CHAN_WIDTH_20;
chandef.center_freq1 = chan->center_freq;
/* check again for downgraded chandef */
if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef,
NL80211_IFTYPE_ADHOC)) {
sdata_info(sdata,
"Failed to join IBSS, beacons forbidden\n");
return;
}
}
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
&chandef, NL80211_IFTYPE_ADHOC);
if (err < 0) {
sdata_info(sdata,
"Failed to join IBSS, invalid chandef\n");
return;
}
if (err > 0 && !ifibss->userspace_handles_dfs) {
sdata_info(sdata,
"Failed to join IBSS, DFS channel without control program\n");
return;
}
radar_required = err;
mutex_lock(&local->mtx);
if (ieee80211_vif_use_channel(sdata, &chandef,
ifibss->fixed_channel ?
IEEE80211_CHANCTX_SHARED :
IEEE80211_CHANCTX_EXCLUSIVE)) {
sdata_info(sdata, "Failed to join IBSS, no channel context\n");
mutex_unlock(&local->mtx);
return;
}
sdata->radar_required = radar_required;
mutex_unlock(&local->mtx);
memcpy(ifibss->bssid, bssid, ETH_ALEN);
presp = ieee80211_ibss_build_presp(sdata, beacon_int, basic_rates,
capability, tsf, &chandef,
&have_higher_than_11mbit, NULL);
if (!presp)
return;
rcu_assign_pointer(ifibss->presp, presp);
mgmt = (void *)presp->head;
sdata->vif.bss_conf.enable_beacon = true;
sdata->vif.bss_conf.beacon_int = beacon_int;
sdata->vif.bss_conf.basic_rates = basic_rates;
sdata->vif.bss_conf.ssid_len = ifibss->ssid_len;
memcpy(sdata->vif.bss_conf.ssid, ifibss->ssid, ifibss->ssid_len);
bss_change = BSS_CHANGED_BEACON_INT;
bss_change |= ieee80211_reset_erp_info(sdata);
bss_change |= BSS_CHANGED_BSSID;
bss_change |= BSS_CHANGED_BEACON;
bss_change |= BSS_CHANGED_BEACON_ENABLED;
bss_change |= BSS_CHANGED_BASIC_RATES;
bss_change |= BSS_CHANGED_HT;
bss_change |= BSS_CHANGED_IBSS;
bss_change |= BSS_CHANGED_SSID;
/*
* In 5 GHz/802.11a, we can always use short slot time.
* (IEEE 802.11-2012 18.3.8.7)
*
* In 2.4GHz, we must always use long slots in IBSS for compatibility
* reasons.
* (IEEE 802.11-2012 19.4.5)
*
* HT follows these specifications (IEEE 802.11-2012 20.3.18)
*/
sdata->vif.bss_conf.use_short_slot = chan->band == NL80211_BAND_5GHZ;
bss_change |= BSS_CHANGED_ERP_SLOT;
/* cf. IEEE 802.11 9.2.12 */
if (chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit)
sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE;
else
sdata->flags &= ~IEEE80211_SDATA_OPERATING_GMODE;
ieee80211_set_wmm_default(sdata, true, false);
sdata->vif.bss_conf.ibss_joined = true;
sdata->vif.bss_conf.ibss_creator = creator;
err = drv_join_ibss(local, sdata);
if (err) {
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
sdata->vif.bss_conf.ssid_len = 0;
RCU_INIT_POINTER(ifibss->presp, NULL);
kfree_rcu(presp, rcu_head);
mutex_lock(&local->mtx);
ieee80211_vif_release_channel(sdata);
mutex_unlock(&local->mtx);
sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
err);
return;
}
ieee80211_bss_info_change_notify(sdata, bss_change);
ifibss->state = IEEE80211_IBSS_MLME_JOINED;
mod_timer(&ifibss->timer,
round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
bss_meta.chan = chan;
bss_meta.scan_width = cfg80211_chandef_to_scan_width(&chandef);
bss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta, mgmt,
presp->head_len, GFP_KERNEL);
cfg80211_put_bss(local->hw.wiphy, bss);
netif_carrier_on(sdata->dev);
cfg80211_ibss_joined(sdata->dev, ifibss->bssid, chan, GFP_KERNEL);
}
static void ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_bss *bss)
{
struct cfg80211_bss *cbss =
container_of((void *)bss, struct cfg80211_bss, priv);
struct ieee80211_supported_band *sband;
struct cfg80211_chan_def chandef;
u32 basic_rates;
int i, j;
u16 beacon_int = cbss->beacon_interval;
const struct cfg80211_bss_ies *ies;
enum nl80211_channel_type chan_type;
u64 tsf;
u32 rate_flags;
int shift;
sdata_assert_lock(sdata);
if (beacon_int < 10)
beacon_int = 10;
switch (sdata->u.ibss.chandef.width) {
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
chan_type = cfg80211_get_chandef_type(&sdata->u.ibss.chandef);
cfg80211_chandef_create(&chandef, cbss->channel, chan_type);
break;
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
cfg80211_chandef_create(&chandef, cbss->channel,
NL80211_CHAN_NO_HT);
chandef.width = sdata->u.ibss.chandef.width;
break;
case NL80211_CHAN_WIDTH_80:
case NL80211_CHAN_WIDTH_80P80:
case NL80211_CHAN_WIDTH_160:
chandef = sdata->u.ibss.chandef;
chandef.chan = cbss->channel;
break;
default:
/* fall back to 20 MHz for unsupported modes */
cfg80211_chandef_create(&chandef, cbss->channel,
NL80211_CHAN_NO_HT);
break;
}
sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
rate_flags = ieee80211_chandef_rate_flags(&sdata->u.ibss.chandef);
shift = ieee80211_vif_get_shift(&sdata->vif);
basic_rates = 0;
for (i = 0; i < bss->supp_rates_len; i++) {
int rate = bss->supp_rates[i] & 0x7f;
bool is_basic = !!(bss->supp_rates[i] & 0x80);
for (j = 0; j < sband->n_bitrates; j++) {
int brate;
if ((rate_flags & sband->bitrates[j].flags)
!= rate_flags)
continue;
brate = DIV_ROUND_UP(sband->bitrates[j].bitrate,
5 * (1 << shift));
if (brate == rate) {
if (is_basic)
basic_rates |= BIT(j);
break;
}
}
}
rcu_read_lock();
ies = rcu_dereference(cbss->ies);
tsf = ies->tsf;
rcu_read_unlock();
__ieee80211_sta_join_ibss(sdata, cbss->bssid,
beacon_int,
&chandef,
basic_rates,
cbss->capability,
tsf, false);
}
int ieee80211_ibss_csa_beacon(struct ieee80211_sub_if_data *sdata,
struct cfg80211_csa_settings *csa_settings)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct beacon_data *presp, *old_presp;
struct cfg80211_bss *cbss;
const struct cfg80211_bss_ies *ies;
u16 capability = WLAN_CAPABILITY_IBSS;
u64 tsf;
sdata_assert_lock(sdata);
if (ifibss->privacy)
capability |= WLAN_CAPABILITY_PRIVACY;
cbss = cfg80211_get_bss(sdata->local->hw.wiphy, ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
if (WARN_ON(!cbss))
return -EINVAL;
rcu_read_lock();
ies = rcu_dereference(cbss->ies);
tsf = ies->tsf;
rcu_read_unlock();
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
old_presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
presp = ieee80211_ibss_build_presp(sdata,
sdata->vif.bss_conf.beacon_int,
sdata->vif.bss_conf.basic_rates,
capability, tsf, &ifibss->chandef,
NULL, csa_settings);
if (!presp)
return -ENOMEM;
rcu_assign_pointer(ifibss->presp, presp);
if (old_presp)
kfree_rcu(old_presp, rcu_head);
return BSS_CHANGED_BEACON;
}
int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct cfg80211_bss *cbss;
sdata_assert_lock(sdata);
/* update cfg80211 bss information with the new channel */
if (!is_zero_ether_addr(ifibss->bssid)) {
cbss = cfg80211_get_bss(sdata->local->hw.wiphy,
ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len,
IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
/* XXX: should not really modify cfg80211 data */
if (cbss) {
cbss->channel = sdata->csa_chandef.chan;
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
}
}
ifibss->chandef = sdata->csa_chandef;
/* generate the beacon */
return ieee80211_ibss_csa_beacon(sdata, NULL);
}
void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
cancel_work_sync(&ifibss->csa_connection_drop_work);
}
static struct sta_info *ieee80211_ibss_finish_sta(struct sta_info *sta)
__acquires(RCU)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
u8 addr[ETH_ALEN];
memcpy(addr, sta->sta.addr, ETH_ALEN);
ibss_dbg(sdata, "Adding new IBSS station %pM\n", addr);
sta_info_pre_move_state(sta, IEEE80211_STA_AUTH);
sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC);
/* authorize the station only if the network is not RSN protected. If
* not wait for the userspace to authorize it */
if (!sta->sdata->u.ibss.control_port)
sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED);
rate_control_rate_init(sta);
/* If it fails, maybe we raced another insertion? */
if (sta_info_insert_rcu(sta))
return sta_info_get(sdata, addr);
return sta;
}
static struct sta_info *
ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata, const u8 *bssid,
const u8 *addr, u32 supp_rates)
__acquires(RCU)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct ieee80211_chanctx_conf *chanctx_conf;
struct ieee80211_supported_band *sband;
enum nl80211_bss_scan_width scan_width;
int band;
/*
* XXX: Consider removing the least recently used entry and
* allow new one to be added.
*/
if (local->num_sta >= IEEE80211_IBSS_MAX_STA_ENTRIES) {
net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n",
sdata->name, addr);
rcu_read_lock();
return NULL;
}
if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) {
rcu_read_lock();
return NULL;
}
if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) {
rcu_read_lock();
return NULL;
}
rcu_read_lock();
chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
if (WARN_ON_ONCE(!chanctx_conf))
return NULL;
band = chanctx_conf->def.chan->band;
scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
rcu_read_unlock();
sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
if (!sta) {
rcu_read_lock();
return NULL;
}
/* make sure mandatory rates are always added */
sband = local->hw.wiphy->bands[band];
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(sband, scan_width);
return ieee80211_ibss_finish_sta(sta);
}
static int ieee80211_sta_active_ibss(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
int active = 0;
struct sta_info *sta;
sdata_assert_lock(sdata);
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
unsigned long last_active = ieee80211_sta_last_active(sta);
if (sta->sdata == sdata &&
time_is_after_jiffies(last_active +
IEEE80211_IBSS_MERGE_INTERVAL)) {
active++;
break;
}
}
rcu_read_unlock();
return active;
}
static void ieee80211_ibss_disconnect(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct cfg80211_bss *cbss;
struct beacon_data *presp;
struct sta_info *sta;
if (!is_zero_ether_addr(ifibss->bssid)) {
cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len,
IEEE80211_BSS_TYPE_IBSS,
IEEE80211_PRIVACY(ifibss->privacy));
if (cbss) {
cfg80211_unlink_bss(local->hw.wiphy, cbss);
cfg80211_put_bss(sdata->local->hw.wiphy, cbss);
}
}
ifibss->state = IEEE80211_IBSS_MLME_SEARCH;
sta_info_flush(sdata);
spin_lock_bh(&ifibss->incomplete_lock);
while (!list_empty(&ifibss->incomplete_stations)) {
sta = list_first_entry(&ifibss->incomplete_stations,
struct sta_info, list);
list_del(&sta->list);
spin_unlock_bh(&ifibss->incomplete_lock);
sta_info_free(local, sta);
spin_lock_bh(&ifibss->incomplete_lock);
}
spin_unlock_bh(&ifibss->incomplete_lock);
netif_carrier_off(sdata->dev);
sdata->vif.bss_conf.ibss_joined = false;
sdata->vif.bss_conf.ibss_creator = false;
sdata->vif.bss_conf.enable_beacon = false;
sdata->vif.bss_conf.ssid_len = 0;
/* remove beacon */
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
BSS_CHANGED_IBSS);
drv_leave_ibss(local, sdata);
mutex_lock(&local->mtx);
ieee80211_vif_release_channel(sdata);
mutex_unlock(&local->mtx);
}
static void ieee80211_csa_connection_drop_work(struct work_struct *work)
{
struct ieee80211_sub_if_data *sdata =
container_of(work, struct ieee80211_sub_if_data,
u.ibss.csa_connection_drop_work);
sdata_lock(sdata);
ieee80211_ibss_disconnect(sdata);
synchronize_rcu();
skb_queue_purge(&sdata->skb_queue);
/* trigger a scan to find another IBSS network to join */
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
sdata_unlock(sdata);
}
static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
int err;
/* if the current channel is a DFS channel, mark the channel as
* unavailable.
*/
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
&ifibss->chandef,
NL80211_IFTYPE_ADHOC);
if (err > 0)
cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
GFP_ATOMIC);
}
static bool
ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
struct ieee802_11_elems *elems,
bool beacon)
{
struct cfg80211_csa_settings params;
struct ieee80211_csa_ie csa_ie;
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
enum nl80211_channel_type ch_type;
int err;
u32 sta_flags;
u32 vht_cap_info = 0;
sdata_assert_lock(sdata);
sta_flags = IEEE80211_STA_DISABLE_VHT;
switch (ifibss->chandef.width) {
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
case NL80211_CHAN_WIDTH_20_NOHT:
sta_flags |= IEEE80211_STA_DISABLE_HT;
fallthrough;
case NL80211_CHAN_WIDTH_20:
sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
break;
default:
break;
}
if (elems->vht_cap_elem)
vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info);
memset(¶ms, 0, sizeof(params));
err = ieee80211_parse_ch_switch_ie(sdata, elems,
ifibss->chandef.chan->band,
vht_cap_info,
sta_flags, ifibss->bssid, &csa_ie);
/* can't switch to destination channel, fail */
if (err < 0)
goto disconnect;
/* did not contain a CSA */
if (err)
return false;
/* channel switch is not supported, disconnect */
if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH))
goto disconnect;
params.count = csa_ie.count;
params.chandef = csa_ie.chandef;
switch (ifibss->chandef.width) {
case NL80211_CHAN_WIDTH_20_NOHT:
case NL80211_CHAN_WIDTH_20:
case NL80211_CHAN_WIDTH_40:
/* keep our current HT mode (HT20/HT40+/HT40-), even if
* another mode has been announced. The mode is not adopted
* within the beacon while doing CSA and we should therefore
* keep the mode which we announce.
*/
ch_type = cfg80211_get_chandef_type(&ifibss->chandef);
cfg80211_chandef_create(¶ms.chandef, params.chandef.chan,
ch_type);
break;
case NL80211_CHAN_WIDTH_5:
case NL80211_CHAN_WIDTH_10:
if (params.chandef.width != ifibss->chandef.width) {
sdata_info(sdata,
"IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
ifibss->bssid,
params.chandef.chan->center_freq,
params.chandef.width,
params.chandef.center_freq1,
params.chandef.center_freq2);
goto disconnect;
}
break;
default:
/* should not happen, sta_flags should prevent VHT modes. */
WARN_ON(1);
goto disconnect;
}
if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef,
NL80211_IFTYPE_ADHOC)) {
sdata_info(sdata,
"IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
ifibss->bssid,
params.chandef.chan->center_freq,
params.chandef.width,
params.chandef.center_freq1,
params.chandef.center_freq2);
goto disconnect;
}
err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
¶ms.chandef,
NL80211_IFTYPE_ADHOC);
if (err < 0)
goto disconnect;
if (err > 0 && !ifibss->userspace_handles_dfs) {
/* IBSS-DFS only allowed with a control program */
goto disconnect;
}
params.radar_required = err;
if (cfg80211_chandef_identical(¶ms.chandef,
&sdata->vif.bss_conf.chandef)) {
ibss_dbg(sdata,
"received csa with an identical chandef, ignoring\n");
return true;
}
/* all checks done, now perform the channel switch. */
ibss_dbg(sdata,
"received channel switch announcement to go to channel %d MHz\n",
params.chandef.chan->center_freq);
params.block_tx = !!csa_ie.mode;
if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
¶ms))
goto disconnect;
ieee80211_ibss_csa_mark_radar(sdata);
return true;
disconnect:
ibss_dbg(sdata, "Can't handle channel switch, disconnect\n");
ieee80211_queue_work(&sdata->local->hw,
&ifibss->csa_connection_drop_work);
ieee80211_ibss_csa_mark_radar(sdata);
return true;
}
static void
ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt, size_t len,
struct ieee80211_rx_status *rx_status,
struct ieee802_11_elems *elems)
{
int required_len;
if (len < IEEE80211_MIN_ACTION_SIZE + 1)
return;
/* CSA is the only action we handle for now */
if (mgmt->u.action.u.measurement.action_code !=
WLAN_ACTION_SPCT_CHL_SWITCH)
return;
required_len = IEEE80211_MIN_ACTION_SIZE +
sizeof(mgmt->u.action.u.chan_switch);
if (len < required_len)
return;
if (!sdata->vif.csa_active)
ieee80211_ibss_process_chanswitch(sdata, elems, false);
}
static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
{
u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code);
if (len < IEEE80211_DEAUTH_FRAME_LEN)
return;
ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason);
sta_info_destroy_addr(sdata, mgmt->sa);
}
static void ieee80211_rx_mgmt_auth_ibss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len)
{
u16 auth_alg, auth_transaction;
sdata_assert_lock(sdata);
if (len < 24 + 6)
return;
auth_alg = le16_to_cpu(mgmt->u.auth.auth_alg);
auth_transaction = le16_to_cpu(mgmt->u.auth.auth_transaction);
ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da);
ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n",
mgmt->bssid, auth_transaction);
if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1)
return;
/*
* IEEE 802.11 standard does not require authentication in IBSS
* networks and most implementations do not seem to use it.
* However, try to reply to authentication attempts if someone
* has actually implemented this.
*/
ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0,
mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0);
}
static void ieee80211_update_sta_info(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt, size_t len,
struct ieee80211_rx_status *rx_status,
struct ieee802_11_elems *elems,
struct ieee80211_channel *channel)
{
struct sta_info *sta;
enum nl80211_band band = rx_status->band;
enum nl80211_bss_scan_width scan_width;
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
bool rates_updated = false;
u32 supp_rates = 0;
if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
return;
if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid))
return;
sband = local->hw.wiphy->bands[band];
if (WARN_ON(!sband))
return;
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);