/*
* 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 "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_MAX_STA_ENTRIES 128
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,
bool creator)
{
struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
struct ieee80211_local *local = sdata->local;
int rates, i;
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];
struct cfg80211_chan_def chandef;
struct beacon_data *presp;
int frame_len;
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);
}
presp = rcu_dereference_protected(ifibss->presp,
lockdep_is_held(&sdata->wdev.mtx));
rcu_assign_pointer(ifibss->presp, NULL);
if (presp)
kfree_rcu(presp, rcu_head);
sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0;
cfg80211_chandef_create(&chandef, chan, ifibss->channel_type);
if (!cfg80211_reg_can_beacon(local->hw.wiphy, &chandef)) {
chandef.width = NL80211_CHAN_WIDTH_20;
chandef.center_freq1 = chan->center_freq;
}
ieee80211_vif_release_channel(sdata);
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");
return;
}
memcpy(ifibss->bssid, bssid, ETH_ALEN);
sband = local->hw.wiphy->bands[chan->band];
/* 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 */ +