diff options
Diffstat (limited to 'net/mac80211/ibss.c')
| -rw-r--r-- | net/mac80211/ibss.c | 1892 |
1 files changed, 1892 insertions, 0 deletions
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c new file mode 100644 index 0000000000..5542c93edf --- /dev/null +++ b/net/mac80211/ibss.c @@ -0,0 +1,1892 @@ +// 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) 2018-2023 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; + u64 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.cfg.ibss_joined) { + sdata->vif.cfg.ibss_joined = false; + sdata->vif.cfg.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 = sdata_dereference(ifibss->presp, sdata); + 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_link_use_channel(&sdata->deflink, &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->deflink.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.cfg.ssid_len = ifibss->ssid_len; + memcpy(sdata->vif.cfg.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 */ + sdata->deflink.operating_11g_mode = + chan->band == NL80211_BAND_2GHZ && have_higher_than_11mbit; + + ieee80211_set_wmm_default(&sdata->deflink, true, false); + + sdata->vif.cfg.ibss_joined = true; + sdata->vif.cfg.ibss_creator = creator; + + err = drv_join_ibss(local, sdata); + if (err) { + sdata->vif.cfg.ibss_joined = false; + sdata->vif.cfg.ibss_creator = false; + sdata->vif.bss_conf.enable_beacon = false; + sdata->vif.cfg.ssid_len = 0; + RCU_INIT_POINTER(ifibss->presp, NULL); + kfree_rcu(presp, rcu_head); + mutex_lock(&local->mtx); + ieee80211_link_release_channel(&sdata->deflink); + 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, + u64 *changed) +{ + 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; + + 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)) + return -EINVAL; + + rcu_read_lock(); + ies = rcu_dereference(cbss->ies); + tsf = ies->tsf; + rcu_read_unlock(); + cfg80211_put_bss(sdata->local->hw.wiphy, cbss); + + old_presp = sdata_dereference(ifibss->presp, sdata); + + 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) + return -ENOMEM; + + rcu_assign_pointer(ifibss->presp, presp); + if (old_presp) + kfree_rcu(old_presp, rcu_head); + + *changed |= BSS_CHANGED_BEACON; + return 0; +} + +int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata, u64 *changed) +{ + struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; + struct cfg80211_bss *cbss; + + sdata_assert_lock(sdata); + + /* When not connected/joined, sending CSA doesn't make sense. */ + if (ifibss->state != IEEE80211_IBSS_MLME_JOINED) + return -ENOLINK; + + /* 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->deflink.csa_chandef.chan; + cfg80211_put_bss(sdata->local->hw.wiphy, cbss); + } + } + + ifibss->chandef = sdata->deflink.csa_chandef; + + /* generate the beacon */ + return ieee80211_ibss_csa_beacon(sdata, NULL, changed); +} + +void ieee80211_ibss_stop(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_if_ibss *ifibss = &sdata->u.ibss; + + wiphy_work_cancel(sdata->local->hw.wiphy, + &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.bss_conf.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.deflink.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.cfg.ibss_joined = false; + sdata->vif.cfg.ibss_creator = false; + sdata->vif.bss_conf.enable_beacon = false; + sdata->vif.cfg.ssid_len = 0; + + /* remove beacon */ + presp = sdata_dereference(ifibss->presp, sdata); + 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_link_release_channel(&sdata->deflink); + mutex_unlock(&local->mtx); +} + +static void ieee80211_csa_connection_drop_work(struct wiphy *wiphy, + struct wiphy_work *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 */ + wiphy_work_queue(sdata->local->hw.wiphy, &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; + ieee80211_conn_flags_t conn_flags; + u32 vht_cap_info = 0; + + sdata_assert_lock(sdata); + + conn_flags = IEEE80211_CONN_DISABLE_VHT; + + switch (ifibss->chandef.width) { + case NL80211_CHAN_WIDTH_5: + case NL80211_CHAN_WIDTH_10: + case NL80211_CHAN_WIDTH_20_NOHT: + conn_flags |= IEEE80211_CONN_DISABLE_HT; + fallthrough; + case NL80211_CHAN_WIDTH_20: + conn_flags |= IEEE80211_CONN_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, + conn_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, conn_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"); + wiphy_work_queue(sdata->local->hw.wiphy, + &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.bss_conf.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.deflink.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.deflink.supp_rates[band] = supp_rates | + ieee80211_mandatory_rates(sband, scan_width); + if (sta->sta.deflink.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.deflink.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.deflink.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->deflink); + + 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.deflink.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, NULL, + &sta->deflink); + if (memcmp(&cap, &sta->sta.deflink.vht_cap, sizeof(cap))) + rates_updated |= true; + } + + if (bw != sta->sta.deflink.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.deflink.rx_nss; + + /* Force rx_nss recalculation */ + sta->sta.deflink.rx_nss = 0; + rate_control_rate_init(sta); + if (sta->sta.deflink.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.bss_conf.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.bss_conf.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.deflink.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); + wiphy_work_queue(local->hw.wiphy, &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 int 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 = sdata_dereference(ifibss->presp, sdata); + + 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; + + elems = ieee802_11_parse_elems(mgmt->u.probe_resp.variable, + len - baselen, false, NULL); + + if (elems) { + ieee80211_rx_bss_info(sdata, mgmt, len, rx_status, elems); + kfree(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; + + elems = ieee802_11_parse_elems( + mgmt->u.action.u.chan_switch.variable, + ies_len, true, NULL); + + if (elems && !elems->parse_error) + ieee80211_rx_mgmt_spectrum_mgmt(sdata, mgmt, + skb->len, + rx_status, + elems); + kfree(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); + + wiphy_work_queue(sdata->local->hw.wiphy, &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); + wiphy_work_init(&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) +{ + u64 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_link_info_change_notify(sdata, &sdata->deflink, changed); + + sdata->deflink.smps_mode = IEEE80211_SMPS_OFF; + sdata->deflink.needed_rx_chains = local->rx_chains; + sdata->control_port_over_nl80211 = params->control_port_over_nl80211; + + wiphy_work_queue(local->hw.wiphy, &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; +} |