1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OCB mode implementation 4 * 5 * Copyright: (c) 2014 Czech Technical University in Prague 6 * (c) 2014 Volkswagen Group Research 7 * Author: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz> 8 * Funded by: Volkswagen Group Research 9 */ 10 11 #include <linux/delay.h> 12 #include <linux/if_ether.h> 13 #include <linux/skbuff.h> 14 #include <linux/if_arp.h> 15 #include <linux/etherdevice.h> 16 #include <linux/rtnetlink.h> 17 #include <net/mac80211.h> 18 #include <asm/unaligned.h> 19 20 #include "ieee80211_i.h" 21 #include "driver-ops.h" 22 #include "rate.h" 23 24 #define IEEE80211_OCB_HOUSEKEEPING_INTERVAL (60 * HZ) 25 #define IEEE80211_OCB_PEER_INACTIVITY_LIMIT (240 * HZ) 26 #define IEEE80211_OCB_MAX_STA_ENTRIES 128 27 28 /** 29 * enum ocb_deferred_task_flags - mac80211 OCB deferred tasks 30 * @OCB_WORK_HOUSEKEEPING: run the periodic OCB housekeeping tasks 31 * 32 * These flags are used in @wrkq_flags field of &struct ieee80211_if_ocb 33 */ 34 enum ocb_deferred_task_flags { 35 OCB_WORK_HOUSEKEEPING, 36 }; 37 38 void ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data *sdata, 39 const u8 *bssid, const u8 *addr, 40 u32 supp_rates) 41 { 42 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 43 struct ieee80211_local *local = sdata->local; 44 struct ieee80211_chanctx_conf *chanctx_conf; 45 struct ieee80211_supported_band *sband; 46 enum nl80211_bss_scan_width scan_width; 47 struct sta_info *sta; 48 int band; 49 50 /* XXX: Consider removing the least recently used entry and 51 * allow new one to be added. 52 */ 53 if (local->num_sta >= IEEE80211_OCB_MAX_STA_ENTRIES) { 54 net_info_ratelimited("%s: No room for a new OCB STA entry %pM\n", 55 sdata->name, addr); 56 return; 57 } 58 59 ocb_dbg(sdata, "Adding new OCB station %pM\n", addr); 60 61 rcu_read_lock(); 62 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 63 if (WARN_ON_ONCE(!chanctx_conf)) { 64 rcu_read_unlock(); 65 return; 66 } 67 band = chanctx_conf->def.chan->band; 68 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 69 rcu_read_unlock(); 70 71 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 72 if (!sta) 73 return; 74 75 /* Add only mandatory rates for now */ 76 sband = local->hw.wiphy->bands[band]; 77 sta->sta.supp_rates[band] = 78 ieee80211_mandatory_rates(sband, scan_width); 79 80 spin_lock(&ifocb->incomplete_lock); 81 list_add(&sta->list, &ifocb->incomplete_stations); 82 spin_unlock(&ifocb->incomplete_lock); 83 ieee80211_queue_work(&local->hw, &sdata->work); 84 } 85 86 static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta) 87 __acquires(RCU) 88 { 89 struct ieee80211_sub_if_data *sdata = sta->sdata; 90 u8 addr[ETH_ALEN]; 91 92 memcpy(addr, sta->sta.addr, ETH_ALEN); 93 94 ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n", 95 addr, sdata->name); 96 97 sta_info_move_state(sta, IEEE80211_STA_AUTH); 98 sta_info_move_state(sta, IEEE80211_STA_ASSOC); 99 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED); 100 101 rate_control_rate_init(sta); 102 103 /* If it fails, maybe we raced another insertion? */ 104 if (sta_info_insert_rcu(sta)) 105 return sta_info_get(sdata, addr); 106 return sta; 107 } 108 109 static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata) 110 { 111 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 112 113 ocb_dbg(sdata, "Running ocb housekeeping\n"); 114 115 ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT); 116 117 mod_timer(&ifocb->housekeeping_timer, 118 round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL)); 119 } 120 121 void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata) 122 { 123 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 124 struct sta_info *sta; 125 126 if (ifocb->joined != true) 127 return; 128 129 sdata_lock(sdata); 130 131 spin_lock_bh(&ifocb->incomplete_lock); 132 while (!list_empty(&ifocb->incomplete_stations)) { 133 sta = list_first_entry(&ifocb->incomplete_stations, 134 struct sta_info, list); 135 list_del(&sta->list); 136 spin_unlock_bh(&ifocb->incomplete_lock); 137 138 ieee80211_ocb_finish_sta(sta); 139 rcu_read_unlock(); 140 spin_lock_bh(&ifocb->incomplete_lock); 141 } 142 spin_unlock_bh(&ifocb->incomplete_lock); 143 144 if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags)) 145 ieee80211_ocb_housekeeping(sdata); 146 147 sdata_unlock(sdata); 148 } 149 150 static void ieee80211_ocb_housekeeping_timer(struct timer_list *t) 151 { 152 struct ieee80211_sub_if_data *sdata = 153 from_timer(sdata, t, u.ocb.housekeeping_timer); 154 struct ieee80211_local *local = sdata->local; 155 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 156 157 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 158 159 ieee80211_queue_work(&local->hw, &sdata->work); 160 } 161 162 void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata) 163 { 164 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 165 166 timer_setup(&ifocb->housekeeping_timer, 167 ieee80211_ocb_housekeeping_timer, 0); 168 INIT_LIST_HEAD(&ifocb->incomplete_stations); 169 spin_lock_init(&ifocb->incomplete_lock); 170 } 171 172 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata, 173 struct ocb_setup *setup) 174 { 175 struct ieee80211_local *local = sdata->local; 176 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 177 u32 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID; 178 int err; 179 180 if (ifocb->joined == true) 181 return -EINVAL; 182 183 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 184 sdata->smps_mode = IEEE80211_SMPS_OFF; 185 sdata->needed_rx_chains = sdata->local->rx_chains; 186 187 mutex_lock(&sdata->local->mtx); 188 err = ieee80211_vif_use_channel(sdata, &setup->chandef, 189 IEEE80211_CHANCTX_SHARED); 190 mutex_unlock(&sdata->local->mtx); 191 if (err) 192 return err; 193 194 ieee80211_bss_info_change_notify(sdata, changed); 195 196 ifocb->joined = true; 197 198 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 199 ieee80211_queue_work(&local->hw, &sdata->work); 200 201 netif_carrier_on(sdata->dev); 202 return 0; 203 } 204 205 int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata) 206 { 207 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 208 struct ieee80211_local *local = sdata->local; 209 struct sta_info *sta; 210 211 ifocb->joined = false; 212 sta_info_flush(sdata); 213 214 spin_lock_bh(&ifocb->incomplete_lock); 215 while (!list_empty(&ifocb->incomplete_stations)) { 216 sta = list_first_entry(&ifocb->incomplete_stations, 217 struct sta_info, list); 218 list_del(&sta->list); 219 spin_unlock_bh(&ifocb->incomplete_lock); 220 221 sta_info_free(local, sta); 222 spin_lock_bh(&ifocb->incomplete_lock); 223 } 224 spin_unlock_bh(&ifocb->incomplete_lock); 225 226 netif_carrier_off(sdata->dev); 227 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); 228 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB); 229 230 mutex_lock(&sdata->local->mtx); 231 ieee80211_vif_release_channel(sdata); 232 mutex_unlock(&sdata->local->mtx); 233 234 skb_queue_purge(&sdata->skb_queue); 235 236 del_timer_sync(&sdata->u.ocb.housekeeping_timer); 237 /* If the timer fired while we waited for it, it will have 238 * requeued the work. Now the work will be running again 239 * but will not rearm the timer again because it checks 240 * whether we are connected to the network or not -- at this 241 * point we shouldn't be anymore. 242 */ 243 244 return 0; 245 } 246