// SPDX-License-Identifier: GPL-2.0-only /* * 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 * Copyright(c) 2018-2020 Intel Corporation */ #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) + 2 + sizeof(struct ieee80211_vht_cap) + 2 + sizeof(struct ieee80211_vht_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->cntdwn_counter_offsets[0] = (pos - presp->head); *pos++ = csa_settings->count; presp->cntdwn_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; } 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); } 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_NO_HT); 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_NO_HT); 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); } 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 = WLAN_CAPABILITY_IBSS; 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; } int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; struct cfg80211_bss *cbss; 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 */ return ieee80211_ibss_csa_beacon(sdata, NULL); } 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); } 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", addr); sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); /* authorize the station only if the network is not RSN protected. If * not wait for the userspace to authorize it */ if (!sta->sdata->u.ibss.control_port) sta_info_pre_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; struct ieee80211_chanctx_conf *chanctx_conf; struct ieee80211_supported_band *sband; enum nl80211_bss_scan_width scan_width; int 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) { net_info_ratelimited("%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 (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) { rcu_read_lock(); return NULL; } rcu_read_lock(); chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); if (WARN_ON_ONCE(!chanctx_conf)) return NULL; band = chanctx_conf->def.chan->band; scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); rcu_read_unlock(); sta = sta_info_alloc(sdata, addr, GFP_KERNEL); if (!sta) { rcu_read_lock(); return NULL; } /* make sure mandatory rates are always added */ sband = local->hw.wiphy->bands[band]; sta->sta.supp_rates[band] = supp_rates | ieee80211_mandatory_rates(sband, scan_width); return ieee80211_ibss_finish_sta(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; sdata_assert_lock(sdata); rcu_read_lock(); list_for_each_entry_rcu(sta, &local->sta_list, list) { unsigned long last_active = ieee80211_sta_last_active(sta); if (sta->sdata == sdata && time_is_after_jiffies(last_active + IEEE80211_IBSS_MERGE_INTERVAL)) { active++; break; } } rcu_read_unlock(); return active; } static void ieee80211_ibss_disconnect(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 beacon_data *presp; struct sta_info *sta; if (!is_zero_ether_addr(ifibss->bssid)) { cbss = cfg80211_get_bss(local->hw.wiphy, ifibss->chandef.chan, ifibss->bssid, ifibss->ssid, ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY(ifibss->privacy)); if (cbss) { cfg80211_unlink_bss(local->hw.wiphy, cbss); cfg80211_put_bss(sdata->local->hw.wiphy, cbss); } } ifibss->state = IEEE80211_IBSS_MLME_SEARCH; sta_info_flush(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); 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; /* remove beacon */ presp = rcu_dereference_protected(ifibss->presp, lockdep_is_held(&sdata->wdev.mtx)); RCU_INIT_POINTER(sdata->u.ibss.presp, NULL); if (presp) kfree_rcu(presp, rcu_head); clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state); ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED | BSS_CHANGED_IBSS); drv_leave_ibss(local, sdata); mutex_lock(&local->mtx); ieee80211_vif_release_channel(sdata); mutex_unlock(&local->mtx); } static void ieee80211_csa_connection_drop_work(struct work_struct *work) { struct ieee80211_sub_if_data *sdata = container_of(work, struct ieee80211_sub_if_data, u.ibss.csa_connection_drop_work); sdata_lock(sdata); ieee80211_ibss_disconnect(sdata); synchronize_rcu(); skb_queue_purge(&sdata->skb_queue); /* trigger a scan to find another IBSS network to join */ ieee80211_queue_work(&sdata->local->hw, &sdata->work); sdata_unlock(sdata); } static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; int err; /* if the current channel is a DFS channel, mark the channel as * unavailable. */ err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, &ifibss->chandef, NL80211_IFTYPE_ADHOC); if (err > 0) cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef, GFP_ATOMIC); } static bool ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata, struct ieee802_11_elems *elems, bool beacon) { struct cfg80211_csa_settings params; struct ieee80211_csa_ie csa_ie; struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; enum nl80211_channel_type ch_type; int err; u32 sta_flags; u32 vht_cap_info = 0; sdata_assert_lock(sdata); sta_flags = IEEE80211_STA_DISABLE_VHT; switch (ifibss->chandef.width) { case NL80211_CHAN_WIDTH_5: case NL80211_CHAN_WIDTH_10: case NL80211_CHAN_WIDTH_20_NOHT: sta_flags |= IEEE80211_STA_DISABLE_HT; fallthrough; case NL80211_CHAN_WIDTH_20: sta_flags |= IEEE80211_STA_DISABLE_40MHZ; break; default: break; } if (elems->vht_cap_elem) vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info); memset(¶ms, 0, sizeof(params)); err = ieee80211_parse_ch_switch_ie(sdata, elems, ifibss->chandef.chan->band, vht_cap_info, sta_flags, ifibss->bssid, &csa_ie); /* can't switch to destination channel, fail */ if (err < 0) goto disconnect; /* did not contain a CSA */ if (err) return false; /* channel switch is not supported, disconnect */ if (!(sdata->local->hw.wiphy->flags & WIPHY_FLAG_HAS_CHANNEL_SWITCH)) goto disconnect; params.count = csa_ie.count; params.chandef = csa_ie.chandef; switch (ifibss->chandef.width) { case NL80211_CHAN_WIDTH_20_NOHT: case NL80211_CHAN_WIDTH_20: case NL80211_CHAN_WIDTH_40: /* keep our current HT mode (HT20/HT40+/HT40-), even if * another mode has been announced. The mode is not adopted * within the beacon while doing CSA and we should therefore * keep the mode which we announce. */ ch_type = cfg80211_get_chandef_type(&ifibss->chandef); cfg80211_chandef_create(¶ms.chandef, params.chandef.chan, ch_type); break; case NL80211_CHAN_WIDTH_5: case NL80211_CHAN_WIDTH_10: if (params.chandef.width != ifibss->chandef.width) { sdata_info(sdata, "IBSS %pM received channel switch from incompatible channel width (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", ifibss->bssid, params.chandef.chan->center_freq, params.chandef.width, params.chandef.center_freq1, params.chandef.center_freq2); goto disconnect; } break; default: /* should not happen, sta_flags should prevent VHT modes. */ WARN_ON(1); goto disconnect; } if (!cfg80211_reg_can_beacon(sdata->local->hw.wiphy, ¶ms.chandef, NL80211_IFTYPE_ADHOC)) { sdata_info(sdata, "IBSS %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n", ifibss->bssid, params.chandef.chan->center_freq, params.chandef.width, params.chandef.center_freq1, params.chandef.center_freq2); goto disconnect; } err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy, ¶ms.chandef, NL80211_IFTYPE_ADHOC); if (err < 0) goto disconnect; if (err > 0 && !ifibss->userspace_handles_dfs) { /* IBSS-DFS only allowed with a control program */ goto disconnect; } params.radar_required = err; if (cfg80211_chandef_identical(¶ms.chandef, &sdata->vif.bss_conf.chandef)) { ibss_dbg(sdata, "received csa with an identical chandef, ignoring\n"); return true; } /* all checks done, now perform the channel switch. */ ibss_dbg(sdata, "received channel switch announcement to go to channel %d MHz\n", params.chandef.chan->center_freq); params.block_tx = !!csa_ie.mode; if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev, ¶ms)) goto disconnect; ieee80211_ibss_csa_mark_radar(sdata); return true; disconnect: ibss_dbg(sdata, "Can't handle channel switch, disconnect\n"); ieee80211_queue_work(&sdata->local->hw, &ifibss->csa_connection_drop_work); ieee80211_ibss_csa_mark_radar(sdata); return true; } static void ieee80211_rx_mgmt_spectrum_mgmt(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, size_t len, struct ieee80211_rx_status *rx_status, struct ieee802_11_elems *elems) { int required_len; if (len < IEEE80211_MIN_ACTION_SIZE + 1) return; /* CSA is the only action we handle for now */ if (mgmt->u.action.u.measurement.action_code != WLAN_ACTION_SPCT_CHL_SWITCH) return; required_len = IEEE80211_MIN_ACTION_SIZE + sizeof(mgmt->u.action.u.chan_switch); if (len < required_len) return; if (!sdata->vif.csa_active) ieee80211_ibss_process_chanswitch(sdata, elems, false); } static void ieee80211_rx_mgmt_deauth_ibss(struct ieee80211_sub_if_data *sdata, struct ieee80211_mgmt *mgmt, size_t len) { u16 reason = le16_to_cpu(mgmt->u.deauth.reason_code); if (len < IEEE80211_DEAUTH_FRAME_LEN) return; ibss_dbg(sdata, "RX DeAuth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da); ibss_dbg(sdata, "\tBSSID=%pM (reason: %d)\n", mgmt->bssid, reason); sta_info_destroy_addr(sdata, mgmt->sa); } 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; sdata_assert_lock(sdata); 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); ibss_dbg(sdata, "RX Auth SA=%pM DA=%pM\n", mgmt->sa, mgmt->da); ibss_dbg(sdata, "\tBSSID=%pM (auth_transaction=%d)\n", mgmt->bssid, auth_transaction); if (auth_alg != WLAN_AUTH_OPEN || auth_transaction != 1) return; /* * 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. */ ieee80211_send_auth(sdata, 2, WLAN_AUTH_OPEN, 0, NULL, 0, mgmt->sa, sdata->u.ibss.bssid, NULL, 0, 0, 0); } static void ieee80211_update_sta_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, struct ieee80211_channel *channel) { struct sta_info *sta; enum nl80211_band band = rx_status->band; enum nl80211_bss_scan_width scan_width; struct ieee80211_local *local = sdata->local; struct ieee80211_supported_band *sband; bool rates_updated = false; u32 supp_rates = 0; if (sdata->vif.type != NL80211_IFTYPE_ADHOC) return; if (!ether_addr_equal(mgmt->bssid, sdata->u.ibss.bssid)) return; sband = local->hw.wiphy->bands[band]; if (WARN_ON(!sband)) return; rcu_read_lock(); sta = sta_info_get(sdata, mgmt->sa); if (elems->supp_rates) { supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); if (sta) { u32 prev_rates; prev_rates = sta->sta.supp_rates[band]; /* make sure mandatory rates are always added */ scan_width = NL80211_BSS_CHAN_WIDTH_20; if (rx_status->bw == RATE_INFO_BW_5) scan_width = NL80211_BSS_CHAN_WIDTH_5; else if (rx_status->bw == RATE_INFO_BW_10) scan_width = NL80211_BSS_CHAN_WIDTH_10; sta->sta.supp_rates[band] = supp_rates | ieee80211_mandatory_rates(sband, scan_width); if (sta->sta.supp_rates[band] != prev_rates) { ibss_dbg(sdata, "updated supp_rates set for %pM based on beacon/probe_resp (0x%x -> 0x%x)\n", sta->sta.addr, prev_rates, sta->sta.supp_rates[band]); rates_updated = true; } } else { rcu_read_unlock(); sta = ieee80211_ibss_add_sta(sdata, mgmt->bssid, mgmt->sa, supp_rates); } } if (sta && !sta->sta.wme && (elems->wmm_info || elems->s1g_capab) && local->hw.queues >= IEEE80211_NUM_ACS) { sta->sta.wme = true; ieee80211_check_fast_xmit(sta); } if (sta && elems->ht_operation && elems->ht_cap_elem && sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20_NOHT && sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_5 && sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_10) { /* we both use HT */ struct ieee80211_ht_cap htcap_ie; struct cfg80211_chan_def chandef; enum ieee80211_sta_rx_bandwidth bw = sta->sta.bandwidth; cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT); ieee80211_chandef_ht_oper(elems->ht_operation, &chandef); memcpy(&htcap_ie, elems->ht_cap_elem, sizeof(htcap_ie)); rates_updated |= ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, &htcap_ie, sta); if (elems->vht_operation && elems->vht_cap_elem && sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_20 && sdata->u.ibss.chandef.width != NL80211_CHAN_WIDTH_40) { /* we both use VHT */ struct ieee80211_vht_cap cap_ie; struct ieee80211_sta_vht_cap cap = sta->sta.vht_cap; u32 vht_cap_info = le32_to_cpu(elems->vht_cap_elem->vht_cap_info); ieee80211_chandef_vht_oper(&local->hw, vht_cap_info, elems->vht_operation, elems->ht_operation, &chandef); memcpy(&cap_ie, elems->vht_cap_elem, sizeof(cap_ie)); ieee80211_vht_cap_ie_to_sta_vht_cap(sdata, sband, &cap_ie, sta); if (memcmp(&cap, &sta->sta.vht_cap, sizeof(cap))) rates_updated |= true; } if (bw != sta->sta.bandwidth) rates_updated |= true; if (!cfg80211_chandef_compatible(&sdata->u.ibss.chandef, &chandef)) WARN_ON_ONCE(1); } if (sta && rates_updated) { u32 changed = IEEE80211_RC_SUPP_RATES_CHANGED; u8 rx_nss = sta->sta.rx_nss; /* Force rx_nss recalculation */ sta->sta.rx_nss = 0; rate_control_rate_init(sta); if (sta->sta.rx_nss != rx_nss) changed |= IEEE80211_RC_NSS_CHANGED; drv_sta_rc_update(local, sdata, &sta->sta, changed); } rcu_read_unlock(); } 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) { struct ieee80211_local *local = sdata->local; struct cfg80211_bss *cbss; struct ieee80211_bss *bss; struct ieee80211_channel *channel; u64 beacon_timestamp, rx_timestamp; u32 supp_rates = 0; enum nl80211_band band = rx_status->band; channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq); if (!channel) return; ieee80211_update_sta_info(sdata, mgmt, len, rx_status, elems, channel); bss = ieee80211_bss_info_update(local, rx_status, mgmt, len, channel); if (!bss) return; cbss = container_of((void *)bss, struct cfg80211_bss, priv); /* same for beacon and probe response */ beacon_timestamp = le64_to_cpu(mgmt->u.beacon.timestamp); /* check if we need to merge IBSS */ /* not an IBSS */ if (!(cbss->capability & WLAN_CAPABILITY_IBSS)) goto put_bss; /* different channel */ if (sdata->u.ibss.fixed_channel && sdata->u.ibss.chandef.chan != cbss->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; /* process channel switch */ if (sdata->vif.csa_active || ieee80211_ibss_process_chanswitch(sdata, elems, true)) goto put_bss; /* same BSSID */ if (ether_addr_equal(cbss->bssid, sdata->u.ibss.bssid)) goto put_bss; /* we use a fixed BSSID */ if (sdata->u.ibss.fixed_bssid) goto put_bss; if (ieee80211_have_rx_timestamp(rx_status)) { /* time when timestamp field was received */ rx_timestamp = ieee80211_calculate_rx_timestamp(local, rx_status, len + FCS_LEN, 24); } else { /* * second best option: get current TSF * (will return -1 if not supported) */ rx_timestamp = drv_get_tsf(local, sdata); } ibss_dbg(sdata, "RX beacon SA=%pM BSSID=%pM TSF=0x%llx\n", mgmt->sa, mgmt->bssid, (unsigned long long)rx_timestamp); ibss_dbg(sdata, "\tBCN=0x%llx diff=%lld @%lu\n", (unsigned long long)beacon_timestamp, (unsigned long long)(rx_timestamp - beacon_timestamp), jiffies); if (beacon_timestamp > rx_timestamp) { ibss_dbg(sdata, "beacon TSF higher than local TSF - IBSS merge with BSSID %pM\n", mgmt->bssid); ieee80211_sta_join_ibss(sdata, bss); supp_rates = ieee80211_sta_get_rates(sdata, elems, band, NULL); 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; struct ieee80211_chanctx_conf *chanctx_conf; struct ieee80211_supported_band *sband; enum nl80211_bss_scan_width scan_width; int 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) { net_info_ratelimited("%s: No room for a new IBSS STA entry %pM\n", sdata->name, addr); return; } if (ifibss->state == IEEE80211_IBSS_MLME_SEARCH) return; if (!ether_addr_equal(bssid, sdata->u.ibss.bssid)) return; rcu_read_lock(); chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); if (WARN_ON_ONCE(!chanctx_conf)) { rcu_read_unlock(); return; } band = chanctx_conf->def.chan->band; scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); rcu_read_unlock(); sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); if (!sta) return; /* make sure mandatory rates are always added */ sband = local->hw.wiphy->bands[band]; sta->sta.supp_rates[band] = supp_rates | ieee80211_mandatory_rates(sband, scan_width); 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 void ieee80211_ibss_sta_expire(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; struct ieee80211_local *local = sdata->local; struct sta_info *sta, *tmp; unsigned long exp_time = IEEE80211_IBSS_INACTIVITY_LIMIT; unsigned long exp_rsn = IEEE80211_IBSS_RSN_INACTIVITY_LIMIT; mutex_lock(&local->sta_mtx); list_for_each_entry_safe(sta, tmp, &local->sta_list, list) { unsigned long last_active = ieee80211_sta_last_active(sta); if (sdata != sta->sdata) continue; if (time_is_before_jiffies(last_active + exp_time) || (time_is_before_jiffies(last_active + exp_rsn) && sta->sta_state != IEEE80211_STA_AUTHORIZED)) { u8 frame_buf[IEEE80211_DEAUTH_FRAME_LEN]; sta_dbg(sta->sdata, "expiring inactive %sSTA %pM\n", sta->sta_state != IEEE80211_STA_AUTHORIZED ? "not authorized " : "", sta->sta.addr); ieee80211_send_deauth_disassoc(sdata, sta->sta.addr, ifibss->bssid, IEEE80211_STYPE_DEAUTH, WLAN_REASON_DEAUTH_LEAVING, true, frame_buf); WARN_ON(__sta_info_destroy(sta)); } } mutex_unlock(&local->sta_mtx); } /* * 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; enum nl80211_bss_scan_width scan_width; sdata_assert_lock(sdata); mod_timer(&ifibss->timer, round_jiffies(jiffies + IEEE80211_IBSS_MERGE_INTERVAL)); ieee80211_ibss_sta_expire(sdata); 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; sdata_info(sdata, "No active IBSS STAs - trying to scan for other IBSS networks with same SSID (merge)\n"); scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, NULL, 0, scan_width); } 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; sdata_assert_lock(sdata); 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; } sdata_info(sdata, "Creating new IBSS network, BSSID %pM\n", bssid); capability = WLAN_CAPABILITY_IBSS; if (ifibss->privacy) capability |= WLAN_CAPABILITY_PRIVACY; __ieee80211_sta_join_ibss(sdata, bssid, sdata->vif.bss_conf.beacon_int, &ifibss->chandef, ifibss->basic_rates, capability, 0, true); } static unsigned ibss_setup_channels(struct wiphy *wiphy, struct ieee80211_channel **channels, unsigned int channels_max, u32 center_freq, u32 width) { struct ieee80211_channel *chan = NULL; unsigned int n_chan = 0; u32 start_freq, end_freq, freq; if (width <= 20) { start_freq = center_freq; end_freq = center_freq; } else { start_freq = center_freq - width / 2 + 10; end_freq = center_freq + width / 2 - 10; } for (freq = start_freq; freq <= end_freq; freq += 20) { chan = ieee80211_get_channel(wiphy, freq); if (!chan) continue; if (n_chan >= channels_max) return n_chan; channels[n_chan] = chan; n_chan++; } return n_chan; } static unsigned int ieee80211_ibss_setup_scan_channels(struct wiphy *wiphy, const struct cfg80211_chan_def *chandef, struct ieee80211_channel **channels, unsigned int channels_max) { unsigned int n_chan = 0; u32 width, cf1, cf2 = 0; switch (chandef->width) { case NL80211_CHAN_WIDTH_40: width = 40; break; case NL80211_CHAN_WIDTH_80P80: cf2 = chandef->center_freq2; fallthrough; case NL80211_CHAN_WIDTH_80: width = 80; break; case NL80211_CHAN_WIDTH_160: width = 160; break; default: width = 20; break; } cf1 = chandef->center_freq1; n_chan = ibss_setup_channels(wiphy, channels, channels_max, cf1, width); if (cf2) n_chan += ibss_setup_channels(wiphy, &channels[n_chan], channels_max - n_chan, cf2, width); return n_chan; } /* * 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; enum nl80211_bss_scan_width scan_width; int active_ibss; sdata_assert_lock(sdata); active_ibss = ieee80211_sta_active_ibss(sdata); ibss_dbg(sdata, "sta_find_ibss (active_ibss=%d)\n", active_ibss); if (active_ibss) return; if (ifibss->fixed_bssid) bssid = ifibss->bssid; if (ifibss->fixed_channel) chan = ifibss->chandef.chan; if (!is_zero_ether_addr(ifibss->bssid)) bssid = ifibss->bssid; cbss = cfg80211_get_bss(local->hw.wiphy, chan, bssid, ifibss->ssid, ifibss->ssid_len, IEEE80211_BSS_TYPE_IBSS, IEEE80211_PRIVACY(ifibss->privacy)); if (cbss) { struct ieee80211_bss *bss; bss = (void *)cbss->priv; ibss_dbg(sdata, "sta_find_ibss: selected %pM current %pM\n", cbss->bssid, ifibss->bssid); sdata_info(sdata, "Selected IBSS BSSID %pM based on configured SSID\n", cbss->bssid); ieee80211_sta_join_ibss(sdata, bss); ieee80211_rx_bss_put(local, bss); return; } /* if a fixed bssid and a fixed freq have been provided create the IBSS * directly and do not waste time scanning */ if (ifibss->fixed_bssid && ifibss->fixed_channel) { sdata_info(sdata, "Created IBSS using preconfigured BSSID %pM\n", bssid); ieee80211_sta_create_ibss(sdata); return; } ibss_dbg(sdata, "sta_find_ibss: did not try to join ibss\n"); /* Selected IBSS not found in current scan results - try to scan */ if (time_after(jiffies, ifibss->last_scan_completed + IEEE80211_SCAN_INTERVAL)) { struct ieee80211_channel *channels[8]; unsigned int num; sdata_info(sdata, "Trigger new scan to find an IBSS to join\n"); scan_width = cfg80211_chandef_to_scan_width(&ifibss->chandef); if (ifibss->fixed_channel) { num = ieee80211_ibss_setup_scan_channels(local->hw.wiphy, &ifibss->chandef, channels, ARRAY_SIZE(channels)); ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, channels, num, scan_width); } else { ieee80211_request_ibss_scan(sdata, ifibss->ssid, ifibss->ssid_len, NULL, 0, scan_width); } } else { int interval = IEEE80211_SCAN_INTERVAL; if (time_after(jiffies, ifibss->ibss_join_req + IEEE80211_IBSS_JOIN_TIMEOUT)) ieee80211_sta_create_ibss(sdata); 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 beacon_data *presp; u8 *pos, *end; sdata_assert_lock(sdata); presp = rcu_dereference_protected(ifibss->presp, lockdep_is_held(&sdata->wdev.mtx)); if (ifibss->state != IEEE80211_IBSS_MLME_JOINED || len < 24 + 2 || !presp) return; tx_last_beacon = drv_tx_last_beacon(local); ibss_dbg(sdata, "RX ProbeReq SA=%pM DA=%pM\n", mgmt->sa, mgmt->da); ibss_dbg(sdata, "\tBSSID=%pM (tx_last_beacon=%d)\n", mgmt->bssid, tx_last_beacon); if (!tx_last_beacon && is_multicast_ether_addr(mgmt->da)) return; if (!ether_addr_equal(mgmt->bssid, ifibss->bssid) && !is_broadcast_ether_addr(mgmt->bssid)) return; end = ((u8 *) mgmt) + len; pos = mgmt->u.probe_req.variable; if (pos[0] != WLAN_EID_SSID || pos + 2 + pos[1] > end) { ibss_dbg(sdata, "Invalid SSID IE in ProbeReq from %pM\n", mgmt->sa); 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 = dev_alloc_skb(local->tx_headroom + presp->head_len); if (!skb) return; skb_reserve(skb, local->tx_headroom); skb_put_data(skb, presp->head, presp->head_len); memcpy(((struct ieee80211_mgmt *) skb->data)->da, mgmt->sa, ETH_ALEN); ibss_dbg(sdata, "Sending ProbeResp to %pM\n", mgmt->sa); IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT; /* avoid excessive retries for probe request to wildcard SSIDs */ if (pos[1] == 0) IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_NO_ACK; ieee80211_tx_skb(sdata, skb); } static void ieee80211_rx_mgmt_probe_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; BUILD_BUG_ON(offsetof(typeof(mgmt->u.probe_resp), variable) != offsetof(typeof(mgmt->u.beacon), variable)); /* * either beacon or probe_resp but the variable field is at the * same offset */ baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt; if (baselen > len) return; ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen, false, &elems, mgmt->bssid, NULL); ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, &elems); } 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; struct ieee802_11_elems elems; int ies_len; rx_status = IEEE80211_SKB_RXCB(skb); mgmt = (struct ieee80211_mgmt *) skb->data; fc = le16_to_cpu(mgmt->frame_control); sdata_lock(sdata); 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: case IEEE80211_STYPE_BEACON: ieee80211_rx_mgmt_probe_beacon(sdata, mgmt, skb->len, rx_status); break; case IEEE80211_STYPE_AUTH: ieee80211_rx_mgmt_auth_ibss(sdata, mgmt, skb->len); break; case IEEE80211_STYPE_DEAUTH: ieee80211_rx_mgmt_deauth_ibss(sdata, mgmt, skb->len); break; case IEEE80211_STYPE_ACTION: switch (mgmt->u.action.category) { case WLAN_CATEGORY_SPECTRUM_MGMT: ies_len = skb->len - offsetof(struct ieee80211_mgmt, u.action.u.chan_switch.variable); if (ies_len < 0) break; ieee802_11_parse_elems( mgmt->u.action.u.chan_switch.variable, ies_len, true, &elems, mgmt->bssid, NULL); if (elems.parse_error) break; ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, skb->len, rx_status, &elems); break; } } mgmt_out: sdata_unlock(sdata); } void ieee80211_ibss_work(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; struct sta_info *sta; sdata_lock(sdata); /* * 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: sdata_unlock(sdata); } static void ieee80211_ibss_timer(struct timer_list *t) { struct ieee80211_sub_if_data *sdata = from_timer(sdata, t, u.ibss.timer); ieee80211_queue_work(&sdata->local->hw, &sdata->work); } void ieee80211_ibss_setup_sdata(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; timer_setup(&ifibss->timer, ieee80211_ibss_timer, 0); INIT_LIST_HEAD(&ifibss->incomplete_stations); spin_lock_init(&ifibss->incomplete_lock); INIT_WORK(&ifibss->csa_connection_drop_work, ieee80211_csa_connection_drop_work); } /* 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; } mutex_unlock(&local->iflist_mtx); } int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, struct cfg80211_ibss_params *params) { u32 changed = 0; u32 rate_flags; struct ieee80211_supported_band *sband; enum ieee80211_chanctx_mode chanmode; struct ieee80211_local *local = sdata->local; int radar_detect_width = 0; int i; int ret; if (params->chandef.chan->freq_offset) { /* this may work, but is untested */ return -EOPNOTSUPP; } ret = cfg80211_chandef_dfs_required(local->hw.wiphy, ¶ms->chandef, sdata->wdev.iftype); if (ret < 0) return ret; if (ret > 0) { if (!params->userspace_handles_dfs) return -EINVAL; radar_detect_width = BIT(params->chandef.width); } chanmode = (params->channel_fixed && !ret) ? IEEE80211_CHANCTX_SHARED : IEEE80211_CHANCTX_EXCLUSIVE; mutex_lock(&local->chanctx_mtx); ret = ieee80211_check_combinations(sdata, ¶ms->chandef, chanmode, radar_detect_width); mutex_unlock(&local->chanctx_mtx); if (ret < 0) return ret; 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.control_port = params->control_port; sdata->u.ibss.userspace_handles_dfs = params->userspace_handles_dfs; sdata->u.ibss.basic_rates = params->basic_rates; sdata->u.ibss.last_scan_completed = jiffies; /* fix basic_rates if channel does not support these rates */ rate_flags = ieee80211_chandef_rate_flags(¶ms->chandef); sband = local->hw.wiphy->bands[params->chandef.chan->band]; for (i = 0; i < sband->n_bitrates; i++) { if ((rate_flags & sband->bitrates[i].flags) != rate_flags) sdata->u.ibss.basic_rates &= ~BIT(i); } 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.chandef = params->chandef; 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; } sdata->u.ibss.state = IEEE80211_IBSS_MLME_SEARCH; sdata->u.ibss.ibss_join_req = jiffies; memcpy(sdata->u.ibss.ssid, params->ssid, params->ssid_len); sdata->u.ibss.ssid_len = params->ssid_len; memcpy(&sdata->u.ibss.ht_capa, ¶ms->ht_capa, sizeof(sdata->u.ibss.ht_capa)); memcpy(&sdata->u.ibss.ht_capa_mask, ¶ms->ht_capa_mask, sizeof(sdata->u.ibss.ht_capa_mask)); /* * 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 | BSS_CHANGED_MCAST_RATE; ieee80211_bss_info_change_notify(sdata, changed); sdata->smps_mode = IEEE80211_SMPS_OFF; sdata->needed_rx_chains = local->rx_chains; sdata->control_port_over_nl80211 = params->control_port_over_nl80211; ieee80211_queue_work(&local->hw, &sdata->work); return 0; } int ieee80211_ibss_leave(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; ieee80211_ibss_disconnect(sdata); ifibss->ssid_len = 0; eth_zero_addr(ifibss->bssid); /* remove beacon */ kfree(sdata->u.ibss.ie); sdata->u.ibss.ie = NULL; sdata->u.ibss.ie_len = 0; /* on the next join, re-program HT parameters */ memset(&ifibss->ht_capa, 0, sizeof(ifibss->ht_capa)); memset(&ifibss->ht_capa_mask, 0, sizeof(ifibss->ht_capa_mask)); synchronize_rcu(); skb_queue_purge(&sdata->skb_queue); del_timer_sync(&sdata->u.ibss.timer); return 0; }