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linux/net/mac80211/ibss.c
Eliad Peller ba1960257c mac80211: update oper_channel on ibss join 
Commit 13c40c5 ("mac80211: Add HT operation modes for IBSS") broke
ibss operation by mistakenly removing the local->oper_channel
update (causing ibss to start on the wrong channel). fix it.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-01-24 14:47:09 -05:00

1200 lines
32 KiB
C
Raw Blame History

/*
* IBSS mode implementation
* Copyright 2003-2008, Jouni Malinen <j@w1.fi>
* Copyright 2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
* Copyright 2009, Johannes Berg <johannes@sipsolutions.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#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 <asm/unaligned.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#define IEEE80211_SCAN_INTERVAL (2 * HZ)
#define IEEE80211_SCAN_INTERVAL_SLOW (15 * 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_MAX_STA_ENTRIES 128
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;
lockdep_assert_held(&sdata->u.ibss.mtx);
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);
/*
* 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.
*/
if (auth_alg == WLAN_AUTH_OPEN && auth_transaction == 1)
ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, NULL, 0,
sdata->u.ibss.bssid, NULL, 0, 0);
}
static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const int beacon_int,
struct ieee80211_channel *chan,
const u32 basic_rates,
const u16 capability, u64 tsf)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int rates, i;
struct sk_buff *skb;
struct ieee80211_mgmt *mgmt;
u8 *pos;
struct ieee80211_supported_band *sband;
struct cfg80211_bss *bss;
u32 bss_change;
u8 supp_rates[IEEE80211_MAX_SUPP_RATES];
enum nl80211_channel_type channel_type;
lockdep_assert_held(&ifibss->mtx);
/* Reset own TSF to allow time synchronization work. */
drv_reset_tsf(local, sdata);
skb = ifibss->skb;
RCU_INIT_POINTER(ifibss->presp, NULL);
synchronize_rcu();
skb->data = skb->head;
skb->len = 0;
skb_reset_tail_pointer(skb);
skb_reserve(skb, sdata->local->hw.extra_tx_headroom);
if (memcmp(ifibss->bssid, bssid, ETH_ALEN))
sta_info_flush(sdata->local, 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;
netif_carrier_off(sdata->dev);
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IBSS);
}
memcpy(ifibss->bssid, bssid, ETH_ALEN);
sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
local->oper_channel = chan;
channel_type = ifibss->channel_type;
if (channel_type > NL80211_CHAN_HT20 &&
!cfg80211_can_beacon_sec_chan(local->hw.wiphy, chan, channel_type))
channel_type = NL80211_CHAN_HT20;
if (!ieee80211_set_channel_type(local, sdata, channel_type)) {
/* can only fail due to HT40+/- mismatch */
channel_type = NL80211_CHAN_HT20;
WARN_ON(!ieee80211_set_channel_type(local, sdata,
NL80211_CHAN_HT20));
}
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
sband = local->hw.wiphy->bands[chan->band];
/* build supported rates array */
pos = supp_rates;
for (i = 0; i < sband->n_bitrates; i++) {
int rate = sband->bitrates[i].bitrate;
u8 basic = 0;
if (basic_rates & BIT(i))
basic = 0x80;
*pos++ = basic | (u8) (rate / 5);
}
/* Build IBSS probe response */
mgmt = (void *) skb_put(skb, 24 + sizeof(mgmt->u.beacon));
memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_PROBE_RESP);
memset(mgmt->da, 0xff, ETH_ALEN);
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 = skb_put(skb, 2 + ifibss->ssid_len);
*pos++ = WLAN_EID_SSID;
*pos++ = ifibss->ssid_len;
memcpy(pos, ifibss->ssid, ifibss->ssid_len);
rates = sband->n_bitrates;
if (rates > 8)
rates = 8;
pos = skb_put(skb, 2 + rates);
*pos++ = WLAN_EID_SUPP_RATES;
*pos++ = rates;
memcpy(pos, supp_rates, rates);
if (sband->band == IEEE80211_BAND_2GHZ) {
pos = skb_put(skb, 2 + 1);
*pos++ = WLAN_EID_DS_PARAMS;
*pos++ = 1;
*pos++ = ieee80211_frequency_to_channel(chan->center_freq);
}
pos = skb_put(skb, 2 + 2);
*pos++ = WLAN_EID_IBSS_PARAMS;
*pos++ = 2;
/* FIX: set ATIM window based on scan results */
*pos++ = 0;
*pos++ = 0;
if (sband->n_bitrates > 8) {
rates = sband->n_bitrates - 8;
pos = skb_put(skb, 2 + rates);
*pos++ = WLAN_EID_EXT_SUPP_RATES;
*pos++ = rates;
memcpy(pos, &supp_rates[8], rates);
}
if (ifibss->ie_len)
memcpy(skb_put(skb, ifibss->ie_len),
ifibss->ie, ifibss->ie_len);
/* add HT capability and information IEs */
if (channel_type && sband->ht_cap.ht_supported) {
pos = skb_put(skb, 4 +
sizeof(struct ieee80211_ht_cap) +
sizeof(struct ieee80211_ht_info));
pos = ieee80211_ie_build_ht_cap(pos, &sband->ht_cap,
sband->ht_cap.cap);
pos = ieee80211_ie_build_ht_info(pos,
&sband->ht_cap,
chan,
channel_type);
}
if (local->hw.queues >= 4) {
pos = skb_put(skb, 9);
*pos++ = WLAN_EID_VENDOR_SPECIFIC;
*pos++ = 7; /* len */
*pos++ = 0x00; /* Microsoft OUI 00:50:F2 */
*pos++ = 0x50;
*pos++ = 0xf2;
*pos++ = 2; /* WME */
*pos++ = 0; /* WME info */
*pos++ = 1; /* WME ver */
*pos++ = 0; /* U-APSD no in use */
}
rcu_assign_pointer(ifibss->presp, skb);
sdata->vif.bss_conf.beacon_int = beacon_int;
sdata->vif.bss_conf.basic_rates = basic_rates;
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;
sdata->vif.bss_conf.ibss_joined = true;
ieee80211_bss_info_change_notify(sdata, bss_change);
ieee80211_sta_def_wmm_params(sdata, sband->n_bitrates, supp_rates);
ifibss->state = IEEE80211_IBSS_MLME_JOINED;
mod_timer(&ifibss->timer,
round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
bss = cfg80211_inform_bss_frame(local->hw.wiphy, local->hw.conf.channel,
mgmt, skb->len, 0, GFP_KERNEL);
cfg80211_put_bss(bss);
netif_carrier_on(sdata->dev);
cfg80211_ibss_joined(sdata->dev, ifibss->bssid, 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;
u32 basic_rates;
int i, j;
u16 beacon_int = cbss->beacon_interval;
lockdep_assert_held(&sdata->u.ibss.mtx);
if (beacon_int < 10)
beacon_int = 10;
sband = sdata->local->hw.wiphy->bands[cbss->channel->band];
basic_rates = 0;
for (i = 0; i < bss->supp_rates_len; i++) {
int rate = (bss->supp_rates[i] & 0x7f) * 5;
bool is_basic = !!(bss->supp_rates[i] & 0x80);
for (j = 0; j < sband->n_bitrates; j++) {
if (sband->bitrates[j].bitrate == rate) {
if (is_basic)
basic_rates |= BIT(j);
break;
}
}
}
__ieee80211_sta_join_ibss(sdata, cbss->bssid,
beacon_int,
cbss->channel,
basic_rates,
cbss->capability,
cbss->tsf);
}
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);
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
wiphy_debug(sdata->local->hw.wiphy,
"Adding new IBSS station %pM (dev=%s)\n",
addr, sdata->name);
#endif
sta_info_move_state(sta, IEEE80211_STA_AUTH);
sta_info_move_state(sta, IEEE80211_STA_ASSOC);
sta_info_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;
int band = local->hw.conf.channel->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) {
if (net_ratelimit())
printk(KERN_DEBUG "%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 (compare_ether_addr(bssid, sdata->u.ibss.bssid)) {
rcu_read_lock();
return NULL;
}
sta = sta_info_alloc(sdata, addr, GFP_KERNEL);
if (!sta) {
rcu_read_lock();
return NULL;
}
sta->last_rx = jiffies;
/* make sure mandatory rates are always added */
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(local, band);
return ieee80211_ibss_finish_sta(sta);
}
static void ieee80211_rx_bss_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,
bool beacon)
{
struct ieee80211_local *local = sdata->local;
int freq;
struct cfg80211_bss *cbss;
struct ieee80211_bss *bss;
struct sta_info *sta;
struct ieee80211_channel *channel;
u64 beacon_timestamp, rx_timestamp;
u32 supp_rates = 0;
enum ieee80211_band band = rx_status->band;
struct ieee80211_supported_band *sband = local->hw.wiphy->bands[band];
bool rates_updated = false;
if (elems->ds_params && elems->ds_params_len == 1)
freq = ieee80211_channel_to_frequency(elems->ds_params[0],
band);
else
freq = rx_status->freq;
channel = ieee80211_get_channel(local->hw.wiphy, freq);
if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
return;
if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);
if (elems->supp_rates) {
supp_rates = ieee80211_sta_get_rates(local, elems,
band);
if (sta) {
u32 prev_rates;
prev_rates = sta->sta.supp_rates[band];
/* make sure mandatory rates are always added */
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(local, band);
if (sta->sta.supp_rates[band] != prev_rates) {
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG
"%s: updated supp_rates set "
"for %pM based on beacon"
"/probe_resp (0x%x -> 0x%x)\n",
sdata->name, sta->sta.addr,
prev_rates,
sta->sta.supp_rates[band]);
#endif
rates_updated = true;
}
} else {
rcu_read_unlock();
sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid,
mgmt->sa, supp_rates);
}
}
if (sta && elems->wmm_info)
set_sta_flag(sta, WLAN_STA_WME);
if (sta && elems->ht_info_elem && elems->ht_cap_elem &&
sdata->u.ibss.channel_type != NL80211_CHAN_NO_HT) {
/* we both use HT */
struct ieee80211_sta_ht_cap sta_ht_cap_new;
enum nl80211_channel_type channel_type =
ieee80211_ht_info_to_channel_type(
elems->ht_info_elem);
ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband,
elems->ht_cap_elem,
&sta_ht_cap_new);
/*
* fall back to HT20 if we don't use or use
* the other extension channel
*/
if ((channel_type == NL80211_CHAN_HT40MINUS ||
channel_type == NL80211_CHAN_HT40PLUS) &&
channel_type != sdata->u.ibss.channel_type)
sta_ht_cap_new.cap &=
~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
if (memcmp(&sta->sta.ht_cap, &sta_ht_cap_new,
sizeof(sta_ht_cap_new))) {
memcpy(&sta->sta.ht_cap, &sta_ht_cap_new,
sizeof(sta_ht_cap_new));
rates_updated = true;
}
}
if (sta && rates_updated)
rate_control_rate_init(sta);
rcu_read_unlock();
}
bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, elems,
channel, beacon);
if (!bss)
return;
cbss = container_of((void *)bss, struct cfg80211_bss, priv);
/* was just updated in ieee80211_bss_info_update */
beacon_timestamp = cbss->tsf;
/* check if we need to merge IBSS */
/* we use a fixed BSSID */
if (sdata->u.ibss.fixed_bssid)
goto put_bss;
/* not an IBSS */
if (!(cbss->capability & WLAN_CAPABILITY_IBSS))
goto put_bss;
/* different channel */
if (cbss->channel != local->oper_channel)
goto put_bss;
/* different SSID */
if (elems->ssid_len != sdata->u.ibss.ssid_len ||
memcmp(elems->ssid, sdata->u.ibss.ssid,
sdata->u.ibss.ssid_len))
goto put_bss;
/* same BSSID */
if (memcmp(cbss->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0)
goto put_bss;
if (rx_status->flag & RX_FLAG_MACTIME_MPDU) {
/*
* For correct IBSS merging we need mactime; since mactime is
* defined as the time the first data symbol of the frame hits
* the PHY, and the timestamp of the beacon is defined as "the
* time that the data symbol containing the first bit of the
* timestamp is transmitted to the PHY plus the transmitting
* STA's delays through its local PHY from the MAC-PHY
* interface to its interface with the WM" (802.11 11.1.2)
* - equals the time this bit arrives at the receiver - we have
* to take into account the offset between the two.
*
* E.g. at 1 MBit that means mactime is 192 usec earlier
* (=24 bytes * 8 usecs/byte) than the beacon timestamp.
*/
int rate;
if (rx_status->flag & RX_FLAG_HT)
rate = 65; /* TODO: HT rates */
else
rate = local->hw.wiphy->bands[band]->
bitrates[rx_status->rate_idx].bitrate;
rx_timestamp = rx_status->mactime + (24 * 8 * 10 / rate);
} else {
/*
* second best option: get current TSF
* (will return -1 if not supported)
*/
rx_timestamp = drv_get_tsf(local, sdata);
}
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "RX beacon SA=%pM BSSID="
"%pM TSF=0x%llx BCN=0x%llx diff=%lld @%lu\n",
mgmt->sa, mgmt->bssid,
(unsigned long long)rx_timestamp,
(unsigned long long)beacon_timestamp,
(unsigned long long)(rx_timestamp - beacon_timestamp),
jiffies);
#endif
if (beacon_timestamp > rx_timestamp) {
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: beacon TSF higher than "
"local TSF - IBSS merge with BSSID %pM\n",
sdata->name, mgmt->bssid);
#endif
ieee80211_sta_join_ibss(sdata, bss);
supp_rates = ieee80211_sta_get_rates(local, elems, band);
ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
supp_rates);
rcu_read_unlock();
}
put_bss:
ieee80211_rx_bss_put(local, bss);
}
void ieee80211_ibss_rx_no_sta(struct ieee80211_sub_if_data *sdata,
const u8 *bssid, const u8 *addr,
u32 supp_rates)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
int band = local->hw.conf.channel->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) {
if (net_ratelimit())
printk(KERN_DEBUG "%s: No room for a new IBSS STA entry %pM\n",
sdata->name, addr);
return;
}
if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
return;
if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
return;
sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
if (!sta)
return;
sta->last_rx = jiffies;
/* make sure mandatory rates are always added */
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(local, band);
spin_lock(&ifibss->incomplete_lock);
list_add(&sta->list, &ifibss->incomplete_stations);
spin_unlock(&ifibss->incomplete_lock);
ieee80211_queue_work(&local->hw, &sdata->work);
}
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;
lockdep_assert_held(&sdata->u.ibss.mtx);
rcu_read_lock();
list_for_each_entry_rcu(sta, &local->sta_list, list) {
if (sta->sdata == sdata &&
time_after(sta->last_rx + IEEE80211_IBSS_MERGE_INTERVAL,
jiffies)) {
active++;
break;
}
}
rcu_read_unlock();
return active;
}
/*
* This function is called with state == IEEE80211_IBSS_MLME_JOINED
*/
static void ieee80211_sta_merge_ibss(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
lockdep_assert_held(&ifibss->mtx);
mod_timer(&ifibss->timer,
round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL));
ieee80211_sta_expire(sdata, IEEE80211_IBSS_INACTIVITY_LIMIT);
if (time_before(jiffies, ifibss->last_scan_completed +
IEEE80211_IBSS_MERGE_INTERVAL))
return;
if (ieee80211_sta_active_ibss(sdata))
return;
if (ifibss->fixed_channel)
return;
printk(KERN_DEBUG "%s: No active IBSS STAs - trying to scan for other "
"IBSS networks with same SSID (merge)\n", sdata->name);
ieee80211_request_internal_scan(sdata,
ifibss->ssid, ifibss->ssid_len,
ifibss->fixed_channel ? ifibss->channel : NULL);
}
static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
u8 bssid[ETH_ALEN];
u16 capability;
int i;
lockdep_assert_held(&ifibss->mtx);
if (ifibss->fixed_bssid) {
memcpy(bssid, ifibss->bssid, ETH_ALEN);
} else {
/* Generate random, not broadcast, locally administered BSSID. Mix in
* own MAC address to make sure that devices that do not have proper
* random number generator get different BSSID. */
get_random_bytes(bssid, ETH_ALEN);
for (i = 0; i < ETH_ALEN; i++)
bssid[i] ^= sdata->vif.addr[i];
bssid[0] &= ~0x01;
bssid[0] |= 0x02;
}
printk(KERN_DEBUG "%s: Creating new IBSS network, BSSID %pM\n",
sdata->name, bssid);
capability = WLAN_CAPABILITY_IBSS;
if (ifibss->privacy)
capability |= WLAN_CAPABILITY_PRIVACY;
else
sdata->drop_unencrypted = 0;
__ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int,
ifibss->channel, ifibss->basic_rates,
capability, 0);
}
/*
* This function is called with state == IEEE80211_IBSS_MLME_SEARCH
*/
static void ieee80211_sta_find_ibss(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 ieee80211_channel *chan = NULL;
const u8 *bssid = NULL;
int active_ibss;
u16 capability;
lockdep_assert_held(&ifibss->mtx);
active_ibss = ieee80211_sta_active_ibss(sdata);
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: sta_find_ibss (active_ibss=%d)\n",
sdata->name, active_ibss);
#endif /* CONFIG_MAC80211_IBSS_DEBUG */
if (active_ibss)
return;
capability = WLAN_CAPABILITY_IBSS;
if (ifibss->privacy)
capability |= WLAN_CAPABILITY_PRIVACY;
if (ifibss->fixed_bssid)
bssid = ifibss->bssid;
if (ifibss->fixed_channel)
chan = ifibss->channel;
if (!is_zero_ether_addr(ifibss->bssid))
bssid = ifibss->bssid;
cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid,
ifibss->ssid, ifibss->ssid_len,
WLAN_CAPABILITY_IBSS | WLAN_CAPABILITY_PRIVACY,
capability);
if (cbss) {
struct ieee80211_bss *bss;
bss = (void *)cbss->priv;
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG " sta_find_ibss: selected %pM current "
"%pM\n", cbss->bssid, ifibss->bssid);
#endif /* CONFIG_MAC80211_IBSS_DEBUG */
printk(KERN_DEBUG "%s: Selected IBSS BSSID %pM"
" based on configured SSID\n",
sdata->name, cbss->bssid);
ieee80211_sta_join_ibss(sdata, bss);
ieee80211_rx_bss_put(local, bss);
return;
}
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG " did not try to join ibss\n");
#endif /* CONFIG_MAC80211_IBSS_DEBUG */
/* Selected IBSS not found in current scan results - try to scan */
if (time_after(jiffies, ifibss->last_scan_completed +
IEEE80211_SCAN_INTERVAL)) {
printk(KERN_DEBUG "%s: Trigger new scan to find an IBSS to "
"join\n", sdata->name);
ieee80211_request_internal_scan(sdata,
ifibss->ssid, ifibss->ssid_len,
ifibss->fixed_channel ? ifibss->channel : NULL);
} else {
int interval = IEEE80211_SCAN_INTERVAL;
if (time_after(jiffies, ifibss->ibss_join_req +
IEEE80211_IBSS_JOIN_TIMEOUT)) {
if (!(local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS)) {
ieee80211_sta_create_ibss(sdata);
return;
}
printk(KERN_DEBUG "%s: IBSS not allowed on"
" %d MHz\n", sdata->name,
local->hw.conf.channel->center_freq);
/* No IBSS found - decrease scan interval and continue
* scanning. */
interval = IEEE80211_SCAN_INTERVAL_SLOW;
}
mod_timer(&ifibss->timer,
round_jiffies(jiffies + interval));
}
}
static void ieee80211_rx_mgmt_probe_req(struct ieee80211_sub_if_data *sdata,
struct sk_buff *req)
{
struct ieee80211_mgmt *mgmt = (void *)req->data;
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int tx_last_beacon, len = req->len;
struct sk_buff *skb;
struct ieee80211_mgmt *resp;
struct sk_buff *presp;
u8 *pos, *end;
lockdep_assert_held(&ifibss->mtx);
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&ifibss->mtx));
if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
len < 24 + 2 || !presp)
return;
tx_last_beacon = drv_tx_last_beacon(local);
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: RX ProbeReq SA=%pM DA=%pM BSSID=%pM"
" (tx_last_beacon=%d)\n",
sdata->name, mgmt->sa, mgmt->da,
mgmt->bssid, tx_last_beacon);
#endif /* CONFIG_MAC80211_IBSS_DEBUG */
if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da))
return;
if (memcmp(mgmt->bssid, ifibss->bssid, ETH_ALEN) != 0 &&
memcmp(mgmt->bssid, "\xff\xff\xff\xff\xff\xff", ETH_ALEN) != 0)
return;
end = ((u8 *) mgmt) + len;
pos = mgmt->u.probe_req.variable;
if (pos[0] != WLAN_EID_SSID ||
pos + 2 + pos[1] > end) {
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: Invalid SSID IE in ProbeReq "
"from %pM\n",
sdata->name, mgmt->sa);
#endif
return;
}
if (pos[1] != 0 &&
(pos[1] != ifibss->ssid_len ||
memcmp(pos + 2, ifibss->ssid, ifibss->ssid_len))) {
/* Ignore ProbeReq for foreign SSID */
return;
}
/* Reply with ProbeResp */
skb = skb_copy(presp, GFP_KERNEL);
if (!skb)
return;
resp = (struct ieee80211_mgmt *) skb->data;
memcpy(resp->da, mgmt->sa, ETH_ALEN);
#ifdef CONFIG_MAC80211_IBSS_DEBUG
printk(KERN_DEBUG "%s: Sending ProbeResp to %pM\n",
sdata->name, resp->da);
#endif /* CONFIG_MAC80211_IBSS_DEBUG */
IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
ieee80211_tx_skb(sdata, skb);
}
static void ieee80211_rx_mgmt_probe_resp(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
size_t baselen;
struct ieee802_11_elems elems;
if (memcmp(mgmt->da, sdata->vif.addr, ETH_ALEN))
return; /* ignore ProbeResp to foreign address */
baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
if (baselen > len)
return;
ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
&elems);
ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, false);
}
static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
struct ieee80211_mgmt *mgmt,
size_t len,
struct ieee80211_rx_status *rx_status)
{
size_t baselen;
struct ieee802_11_elems elems;
/* Process beacon from the current BSS */
baselen = (u8 *) mgmt->u.beacon.variable - (u8 *) mgmt;
if (baselen > len)
return;
ieee802_11_parse_elems(mgmt->u.beacon.variable, len - baselen, &elems);
ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems, true);
}
void ieee80211_ibss_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
struct sk_buff *skb)
{
struct ieee80211_rx_status *rx_status;
struct ieee80211_mgmt *mgmt;
u16 fc;
rx_status = IEEE80211_SKB_RXCB(skb);
mgmt = (struct ieee80211_mgmt *) skb->data;
fc = le16_to_cpu(mgmt->frame_control);
mutex_lock(&sdata->u.ibss.mtx);
if (!sdata->u.ibss.ssid_len)
goto mgmt_out; /* not ready to merge yet */
switch (fc & IEEE80211_FCTL_STYPE) {
case IEEE80211_STYPE_PROBE_REQ:
ieee80211_rx_mgmt_probe_req(sdata, skb);
break;
case IEEE80211_STYPE_PROBE_RESP:
ieee80211_rx_mgmt_probe_resp(sdata, mgmt, skb->len,
rx_status);
break;
case IEEE80211_STYPE_BEACON:
ieee80211_rx_mgmt_beacon(sdata, mgmt, skb->len,
rx_status);
break;
case IEEE80211_STYPE_AUTH:
ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len);
break;
}
mgmt_out:
mutex_unlock(&sdata->u.ibss.mtx);
}
void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct sta_info *sta;
mutex_lock(&ifibss->mtx);
/*
* Work could be scheduled after scan or similar
* when we aren't even joined (or trying) with a
* network.
*/
if (!ifibss->ssid_len)
goto out;
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);
ieee80211_ibss_finish_sta(sta);
rcu_read_unlock();
spin_lock_bh(&ifibss->incomplete_lock);
}
spin_unlock_bh(&ifibss->incomplete_lock);
switch (ifibss->state) {
case IEEE80211_IBSS_MLME_SEARCH:
ieee80211_sta_find_ibss(sdata);
break;
case IEEE80211_IBSS_MLME_JOINED:
ieee80211_sta_merge_ibss(sdata);
break;
default:
WARN_ON(1);
break;
}
out:
mutex_unlock(&ifibss->mtx);
}
static void ieee80211_ibss_timer(unsigned long data)
{
struct ieee80211_sub_if_data *sdata =
(struct ieee80211_sub_if_data *) data;
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
if (local->quiescing) {
ifibss->timer_running = true;
return;
}
ieee80211_queue_work(&local->hw, &sdata->work);
}
#ifdef CONFIG_PM
void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
if (del_timer_sync(&ifibss->timer))
ifibss->timer_running = true;
}
void ieee80211_ibss_restart(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
if (ifibss->timer_running) {
add_timer(&ifibss->timer);
ifibss->timer_running = false;
}
}
#endif
void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
setup_timer(&ifibss->timer, ieee80211_ibss_timer,
(unsigned long) sdata);
mutex_init(&ifibss->mtx);
INIT_LIST_HEAD(&ifibss->incomplete_stations);
spin_lock_init(&ifibss->incomplete_lock);
}
/* scan finished notification */
void ieee80211_ibss_notify_scan_completed(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (sdata->vif.type != NL80211_IFTYPE_ADHOC)
continue;
sdata->u.ibss.last_scan_completed = jiffies;
ieee80211_queue_work(&local->hw, &sdata->work);
}
mutex_unlock(&local->iflist_mtx);
}
int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
struct cfg80211_ibss_params *params)
{
struct sk_buff *skb;
u32 changed = 0;
skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
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 */ +
2 + (IEEE80211_MAX_SUPP_RATES - 8) +
2 + sizeof(struct ieee80211_ht_cap) +
2 + sizeof(struct ieee80211_ht_info) +
params->ie_len);
if (!skb)
return -ENOMEM;
mutex_lock(&sdata->u.ibss.mtx);
if (params->bssid) {
memcpy(sdata->u.ibss.bssid, params->bssid, ETH_ALEN);
sdata->u.ibss.fixed_bssid = true;
} else
sdata->u.ibss.fixed_bssid = false;
sdata->u.ibss.privacy = params->privacy;
sdata->u.ibss.basic_rates = params->basic_rates;
memcpy(sdata->vif.bss_conf.mcast_rate, params->mcast_rate,
sizeof(params->mcast_rate));
sdata->vif.bss_conf.beacon_int = params->beacon_interval;
sdata->u.ibss.channel = params->channel;
sdata->u.ibss.channel_type = params->channel_type;
sdata->u.ibss.fixed_channel = params->channel_fixed;
/* fix ourselves to that channel now already */
if (params->channel_fixed) {
sdata->local->oper_channel = params->channel;
if (!ieee80211_set_channel_type(sdata->local, sdata,
params->channel_type)) {
mutex_unlock(&sdata->u.ibss.mtx);
kfree_skb(skb);
return -EINVAL;
}
}
if (params->ie) {
sdata->u.ibss.ie = kmemdup(params->ie, params->ie_len,
GFP_KERNEL);
if (sdata->u.ibss.ie)
sdata->u.ibss.ie_len = params->ie_len;
}
sdata->u.ibss.skb = skb;
sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
sdata->u.ibss.ibss_join_req = jiffies;
memcpy(sdata->u.ibss.ssid, params->ssid, IEEE80211_MAX_SSID_LEN);
sdata->u.ibss.ssid_len = params->ssid_len;
mutex_unlock(&sdata->u.ibss.mtx);
mutex_lock(&sdata->local->mtx);
ieee80211_recalc_idle(sdata->local);
mutex_unlock(&sdata->local->mtx);
/*
* 802.11n-2009 9.13.3.1: In an IBSS, the HT Protection field is
* reserved, but an HT STA shall protect HT transmissions as though
* the HT Protection field were set to non-HT mixed mode.
*
* In an IBSS, the RIFS Mode field of the HT Operation element is
* also reserved, but an HT STA shall operate as though this field
* were set to 1.
*/
sdata->vif.bss_conf.ht_operation_mode |=
IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED
| IEEE80211_HT_PARAM_RIFS_MODE;
changed |= BSS_CHANGED_HT;
ieee80211_bss_info_change_notify(sdata, changed);
ieee80211_queue_work(&sdata->local->hw, &sdata->work);
return 0;
}
int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
{
struct sk_buff *skb;
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct cfg80211_bss *cbss;
u16 capability;
int active_ibss;
struct sta_info *sta;
mutex_lock(&sdata->u.ibss.mtx);
sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH;
memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
sdata->u.ibss.ssid_len = 0;
active_ibss = ieee80211_sta_active_ibss(sdata);
if (!active_ibss && !is_zero_ether_addr(ifibss->bssid)) {
capability = WLAN_CAPABILITY_IBSS;
if (ifibss->privacy)
capability |= WLAN_CAPABILITY_PRIVACY;
cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->channel,
ifibss->bssid, ifibss->ssid,
ifibss->ssid_len, WLAN_CAPABILITY_IBSS |
WLAN_CAPABILITY_PRIVACY,
capability);
if (cbss) {
cfg80211_unlink_bss(local->hw.wiphy, cbss);
cfg80211_put_bss(cbss);
}
}
sta_info_flush(sdata->local, 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);
/* remove beacon */
kfree(sdata->u.ibss.ie);
skb = rcu_dereference_protected(sdata->u.ibss.presp,
lockdep_is_held(&sdata->u.ibss.mtx));
RCU_INIT_POINTER(sdata->u.ibss.presp, NULL);
sdata->vif.bss_conf.ibss_joined = false;
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED |
BSS_CHANGED_IBSS);
synchronize_rcu();
kfree_skb(skb);
skb_queue_purge(&sdata->skb_queue);
del_timer_sync(&sdata->u.ibss.timer);
mutex_unlock(&sdata->u.ibss.mtx);
mutex_lock(&local->mtx);
ieee80211_recalc_idle(sdata->local);
mutex_unlock(&local->mtx);
return 0;
}
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