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linux/net/mac80211/ibss.c
Johannes Berg 34e895075e mac80211: allow station add/remove to sleep 
Many drivers would like to sleep during station
addition and removal, and currently have a high
complexity there from not being able to.

This introduces two new callbacks sta_add() and
sta_remove() that drivers can implement instead
of using sta_notify() and that can sleep, and
the new sta_add() callback is also allowed to
fail.

The reason we didn't do this previously is that
the IBSS code wants to insert stations from the
RX path, which is a tasklet, so cannot sleep.
This patch will keep the station allocation in
that path, but moves adding the station to the
driver out of line. Since the addition can now
fail, we can have IBSS peer structs the driver
rejected -- in that case we still talk to the
station but never tell the driver about it in
the control.sta pointer. If there will ever be
a driver that has a low limit on the number of
stations and that cannot talk to any stations
that are not known to it, we need to do come up
with a new strategy of handling larger IBSSs,
maybe quicker expiry or rejecting peers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-02-08 16:50:53 -05:00

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/*
* 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/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_MERGE_DELAY 0x400000
#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, status_code;
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);
status_code = le16_to_cpu(mgmt->u.auth.status_code);
/*
* 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];
/* Reset own TSF to allow time synchronization work. */
drv_reset_tsf(local);
skb = ifibss->skb;
rcu_assign_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);
memcpy(ifibss->bssid, bssid, ETH_ALEN);
sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
local->oper_channel = chan;
local->oper_channel_type = NL80211_CHAN_NO_HT;
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);
rcu_assign_pointer(ifibss->presp, skb);
sdata->vif.bss_conf.beacon_int = beacon_int;
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;
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);
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;
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 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;
if (elems->ds_params && elems->ds_params_len == 1)
freq = ieee80211_channel_to_frequency(elems->ds_params[0]);
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 && elems->supp_rates &&
memcmp(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN) == 0) {
supp_rates = ieee80211_sta_get_rates(local, elems, band);
rcu_read_lock();
sta = sta_info_get(sdata, mgmt->sa);
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);
#ifdef CONFIG_MAC80211_IBSS_DEBUG
if (sta->sta.supp_rates[band] != prev_rates)
printk(KERN_DEBUG "%s: updated supp_rates set "
"for %pM based on beacon info (0x%llx | "
"0x%llx -> 0x%llx)\n",
sdata->name,
sta->sta.addr,
(unsigned long long) prev_rates,
(unsigned long long) supp_rates,
(unsigned long long) sta->sta.supp_rates[band]);
#endif
rcu_read_unlock();
} else {
rcu_read_unlock();
ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
supp_rates, GFP_KERNEL);
}
}
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_TSFT) {
/*
* 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);
}
#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
/* give slow hardware some time to do the TSF sync */
if (rx_timestamp < IEEE80211_IBSS_MERGE_DELAY)
goto put_bss;
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);
ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa,
supp_rates, GFP_KERNEL);
}
put_bss:
ieee80211_rx_bss_put(local, bss);
}
/*
* Add a new IBSS station, will also be called by the RX code when,
* in IBSS mode, receiving a frame from a yet-unknown station, hence
* must be callable in atomic context.
*/
struct sta_info *ieee80211_ibss_add_sta(struct ieee80211_sub_if_data *sdata,
u8 *bssid,u8 *addr, u32 supp_rates,
gfp_t gfp)
{
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 NULL;
}
if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH)
return NULL;
if (compare_ether_addr(bssid, sdata->u.ibss.bssid))
return NULL;
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
printk(KERN_DEBUG "%s: Adding new IBSS station %pM (dev=%s)\n",
wiphy_name(local->hw.wiphy), addr, sdata->name);
#endif
sta = sta_info_alloc(sdata, addr, gfp);
if (!sta)
return NULL;
set_sta_flags(sta, WLAN_STA_AUTHORIZED);
/* make sure mandatory rates are always added */
sta->sta.supp_rates[band] = supp_rates |
ieee80211_mandatory_rates(local, band);
rate_control_rate_init(sta);
/* If it fails, maybe we raced another insertion? */
if (sta_info_insert(sta))
return sta_info_get(sdata, addr);
return 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;
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;
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);
}
static void ieee80211_sta_create_ibss(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
struct ieee80211_supported_band *sband;
u8 bssid[ETH_ALEN];
u16 capability;
int i;
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);
sband = local->hw.wiphy->bands[ifibss->channel->band];
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, 3, /* first two are basic */
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;
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);
} 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 ieee80211_mgmt *mgmt,
size_t len)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int tx_last_beacon;
struct sk_buff *skb;
struct ieee80211_mgmt *resp;
u8 *pos, *end;
if (ifibss->state != IEEE80211_IBSS_MLME_JOINED ||
len < 24 + 2 || !ifibss->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)
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(ifibss->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);
}
static 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);
switch (fc & IEEE80211_FCTL_STYPE) {
case IEEE80211_STYPE_PROBE_REQ:
ieee80211_rx_mgmt_probe_req(sdata, mgmt, skb->len);
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;
}
kfree_skb(skb);
}
static void ieee80211_ibss_work(struct work_struct *work)
{
struct ieee80211_sub_if_data *sdata =
container_of(work, struct ieee80211_sub_if_data, u.ibss.work);
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_ibss *ifibss;
struct sk_buff *skb;
if (WARN_ON(local->suspended))
return;
if (!ieee80211_sdata_running(sdata))
return;
if (local->scanning)
return;
if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_ADHOC))
return;
ifibss = &sdata->u.ibss;
while ((skb = skb_dequeue(&ifibss->skb_queue)))
ieee80211_ibss_rx_queued_mgmt(sdata, skb);
if (!test_and_clear_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request))
return;
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;
}
}
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;
}
set_bit(IEEE80211_IBSS_REQ_RUN, &ifibss->request);
ieee80211_queue_work(&local->hw, &ifibss->work);
}
#ifdef CONFIG_PM
void ieee80211_ibss_quiesce(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
cancel_work_sync(&ifibss->work);
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;
INIT_WORK(&ifibss->work, ieee80211_ibss_work);
setup_timer(&ifibss->timer, ieee80211_ibss_timer,
(unsigned long) sdata);
skb_queue_head_init(&ifibss->skb_queue);
}
/* 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;
if (!sdata->u.ibss.ssid_len)
continue;
sdata->u.ibss.last_scan_completed = jiffies;
mod_timer(&sdata->u.ibss.timer, 0);
}
mutex_unlock(&local->iflist_mtx);
}
ieee80211_rx_result
ieee80211_ibss_rx_mgmt(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_mgmt *mgmt;
u16 fc;
if (skb->len < 24)
return RX_DROP_MONITOR;
mgmt = (struct ieee80211_mgmt *) skb->data;
fc = le16_to_cpu(mgmt->frame_control);
switch (fc & IEEE80211_FCTL_STYPE) {
case IEEE80211_STYPE_PROBE_RESP:
case IEEE80211_STYPE_BEACON:
case IEEE80211_STYPE_PROBE_REQ:
case IEEE80211_STYPE_AUTH:
skb_queue_tail(&sdata->u.ibss.skb_queue, skb);
ieee80211_queue_work(&local->hw, &sdata->u.ibss.work);
return RX_QUEUED;
}
return RX_DROP_MONITOR;
}
int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata,
struct cfg80211_ibss_params *params)
{
struct sk_buff *skb;
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->vif.bss_conf.beacon_int = params->beacon_interval;
sdata->u.ibss.channel = params->channel;
sdata->u.ibss.fixed_channel = params->channel_fixed;
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;
}
skb = dev_alloc_skb(sdata->local->hw.extra_tx_headroom +
36 /* bitrates */ +
34 /* SSID */ +
3 /* DS params */ +
4 /* IBSS params */ +
params->ie_len);
if (!skb)
return -ENOMEM;
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);
/*
* The ssid_len setting below is used to see whether
* we are active, and we need all other settings
* before that may get visible.
*/
mb();
sdata->u.ibss.ssid_len = params->ssid_len;
ieee80211_recalc_idle(sdata->local);
set_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
ieee80211_queue_work(&sdata->local->hw, &sdata->u.ibss.work);
return 0;
}
int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata)
{
struct sk_buff *skb;
del_timer_sync(&sdata->u.ibss.timer);
clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
cancel_work_sync(&sdata->u.ibss.work);
clear_bit(IEEE80211_IBSS_REQ_RUN, &sdata->u.ibss.request);
sta_info_flush(sdata->local, sdata);
/* remove beacon */
kfree(sdata->u.ibss.ie);
skb = sdata->u.ibss.presp;
rcu_assign_pointer(sdata->u.ibss.presp, NULL);
ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
synchronize_rcu();
kfree_skb(skb);
skb_queue_purge(&sdata->u.ibss.skb_queue);
memset(sdata->u.ibss.bssid, 0, ETH_ALEN);
sdata->u.ibss.ssid_len = 0;
ieee80211_recalc_idle(sdata->local);
return 0;
}
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