/*
* 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_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);
/* 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;
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;
WARN_ON(!ieee80211_set_channel_type(local, sdata, 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);