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Release 4.8 net/mac80211/ibss.c

Directory: net/mac80211
/*
 * 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>
 * Copyright 2013-2014  Intel Mobile Communications GmbH
 * Copyright(c) 2016 Intel Deutschland GmbH
 *
 * 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_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) + 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->csa_counter_offsets[0] = (pos - presp->head); *pos++ = csa_settings->count; presp->csa_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; }

Contributors

PersonTokensPropCommitsCommitProp
simon wunderlichsimon wunderlich59256.76%620.00%
johannes bergjohannes berg35934.42%1446.67%
janusz dziedzicjanusz dziedzic555.27%13.33%
chun-yeow yeohchun-yeow yeoh80.77%13.33%
sujith manoharansujith manoharan70.67%26.67%
arik nemtsovarik nemtsov70.67%26.67%
alexander simonalexander simon70.67%13.33%
eliad pellereliad peller30.29%13.33%
andrei otcheretianskiandrei otcheretianski30.29%13.33%
michal kaziormichal kazior20.19%13.33%
Total1043100.00%30100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
simon wunderlichsimon wunderlich45350.56%821.62%
johannes bergjohannes berg30934.49%1437.84%
marek puzyniakmarek puzyniak353.91%12.70%
luciano coelholuciano coelho202.23%25.41%
alexander simonalexander simon182.01%12.70%
john w. linvillejohn w. linville151.67%12.70%
teemu paasikiviteemu paasikivi141.56%25.41%
sujith manoharansujith manoharan101.12%12.70%
eliad pellereliad peller70.78%12.70%
michal kaziormichal kazior60.67%12.70%
ilan peerilan peer40.45%12.70%
antonio quartulliantonio quartulli20.22%12.70%
ashok nagarajanashok nagarajan10.11%12.70%
monam agarwalmonam agarwal10.11%12.70%
eric dumazeteric dumazet10.11%12.70%
Total896100.00%37100.00%


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_WIDTH_20_NOHT); 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_WIDTH_20_NOHT); 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); }

Contributors

PersonTokensPropCommitsCommitProp
johannes bergjohannes berg23052.75%857.14%
simon wunderlichsimon wunderlich17439.91%214.29%
janusz dziedzicjanusz dziedzic255.73%17.14%
sujith manoharansujith manoharan40.92%214.29%
jouni malinenjouni malinen30.69%17.14%
Total436100.00%14100.00%


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 = 0; u64 tsf; int ret = 0; 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)) { ret = -EINVAL; goto out; } 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) { ret = -ENOMEM; goto out; } rcu_assign_pointer(ifibss->presp, presp); if (old_presp) kfree_rcu(old_presp, rcu_head); return BSS_CHANGED_BEACON; out: return ret; }

Contributors

PersonTokensPropCommitsCommitProp
simon wunderlichsimon wunderlich16462.12%228.57%
johannes bergjohannes berg8331.44%228.57%
dedy lanskydedy lansky103.79%114.29%
ashok nagarajanashok nagarajan51.89%114.29%
luciano coelholuciano coelho20.76%114.29%
Total264100.00%7100.00%


int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; struct cfg80211_bss *cbss; int err, changed = 0; 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 */ err = ieee80211_ibss_csa_beacon(sdata, NULL); if (err < 0) return err; changed |= err; return changed; }

Contributors

PersonTokensPropCommitsCommitProp
simon wunderlichsimon wunderlich10567.31%330.00%
antonio quartulliantonio quartulli3421.79%330.00%
dedy lanskydedy lansky74.49%110.00%
michal kaziormichal kazior74.49%110.00%
luciano coelholuciano coelho21.28%110.00%
johannes bergjohannes berg10.64%110.00%
Total156100.00%10100.00%


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); }

Contributors

PersonTokensPropCommitsCommitProp
simon wunderlichsimon wunderlich30100.00%2100.00%
Total30100.00%2100.00%


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"