1 /* 2 * OCB mode implementation 3 * 4 * Copyright: (c) 2014 Czech Technical University in Prague 5 * (c) 2014 Volkswagen Group Research 6 * Author: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz> 7 * Funded by: Volkswagen Group Research 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include <linux/delay.h> 15 #include <linux/if_ether.h> 16 #include <linux/skbuff.h> 17 #include <linux/if_arp.h> 18 #include <linux/etherdevice.h> 19 #include <linux/rtnetlink.h> 20 #include <net/mac80211.h> 21 #include <asm/unaligned.h> 22 23 #include "ieee80211_i.h" 24 #include "driver-ops.h" 25 #include "rate.h" 26 27 #define IEEE80211_OCB_HOUSEKEEPING_INTERVAL (60 * HZ) 28 #define IEEE80211_OCB_PEER_INACTIVITY_LIMIT (240 * HZ) 29 #define IEEE80211_OCB_MAX_STA_ENTRIES 128 30 31 /** 32 * enum ocb_deferred_task_flags - mac80211 OCB deferred tasks 33 * @OCB_WORK_HOUSEKEEPING: run the periodic OCB housekeeping tasks 34 * 35 * These flags are used in @wrkq_flags field of &struct ieee80211_if_ocb 36 */ 37 enum ocb_deferred_task_flags { 38 OCB_WORK_HOUSEKEEPING, 39 }; 40 41 void ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data *sdata, 42 const u8 *bssid, const u8 *addr, 43 u32 supp_rates) 44 { 45 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 46 struct ieee80211_local *local = sdata->local; 47 struct ieee80211_chanctx_conf *chanctx_conf; 48 struct ieee80211_supported_band *sband; 49 enum nl80211_bss_scan_width scan_width; 50 struct sta_info *sta; 51 int band; 52 53 /* XXX: Consider removing the least recently used entry and 54 * allow new one to be added. 55 */ 56 if (local->num_sta >= IEEE80211_OCB_MAX_STA_ENTRIES) { 57 net_info_ratelimited("%s: No room for a new OCB STA entry %pM\n", 58 sdata->name, addr); 59 return; 60 } 61 62 ocb_dbg(sdata, "Adding new OCB station %pM\n", addr); 63 64 rcu_read_lock(); 65 chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf); 66 if (WARN_ON_ONCE(!chanctx_conf)) { 67 rcu_read_unlock(); 68 return; 69 } 70 band = chanctx_conf->def.chan->band; 71 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def); 72 rcu_read_unlock(); 73 74 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC); 75 if (!sta) 76 return; 77 78 sta->rx_stats.last_rx = jiffies; 79 80 /* Add only mandatory rates for now */ 81 sband = local->hw.wiphy->bands[band]; 82 sta->sta.supp_rates[band] = 83 ieee80211_mandatory_rates(sband, scan_width); 84 85 spin_lock(&ifocb->incomplete_lock); 86 list_add(&sta->list, &ifocb->incomplete_stations); 87 spin_unlock(&ifocb->incomplete_lock); 88 ieee80211_queue_work(&local->hw, &sdata->work); 89 } 90 91 static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta) 92 __acquires(RCU) 93 { 94 struct ieee80211_sub_if_data *sdata = sta->sdata; 95 u8 addr[ETH_ALEN]; 96 97 memcpy(addr, sta->sta.addr, ETH_ALEN); 98 99 ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n", 100 addr, sdata->name); 101 102 sta_info_move_state(sta, IEEE80211_STA_AUTH); 103 sta_info_move_state(sta, IEEE80211_STA_ASSOC); 104 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED); 105 106 rate_control_rate_init(sta); 107 108 /* If it fails, maybe we raced another insertion? */ 109 if (sta_info_insert_rcu(sta)) 110 return sta_info_get(sdata, addr); 111 return sta; 112 } 113 114 static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata) 115 { 116 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 117 118 ocb_dbg(sdata, "Running ocb housekeeping\n"); 119 120 ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT); 121 122 mod_timer(&ifocb->housekeeping_timer, 123 round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL)); 124 } 125 126 void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata) 127 { 128 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 129 struct sta_info *sta; 130 131 if (ifocb->joined != true) 132 return; 133 134 sdata_lock(sdata); 135 136 spin_lock_bh(&ifocb->incomplete_lock); 137 while (!list_empty(&ifocb->incomplete_stations)) { 138 sta = list_first_entry(&ifocb->incomplete_stations, 139 struct sta_info, list); 140 list_del(&sta->list); 141 spin_unlock_bh(&ifocb->incomplete_lock); 142 143 ieee80211_ocb_finish_sta(sta); 144 rcu_read_unlock(); 145 spin_lock_bh(&ifocb->incomplete_lock); 146 } 147 spin_unlock_bh(&ifocb->incomplete_lock); 148 149 if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags)) 150 ieee80211_ocb_housekeeping(sdata); 151 152 sdata_unlock(sdata); 153 } 154 155 static void ieee80211_ocb_housekeeping_timer(unsigned long data) 156 { 157 struct ieee80211_sub_if_data *sdata = (void *)data; 158 struct ieee80211_local *local = sdata->local; 159 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 160 161 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 162 163 ieee80211_queue_work(&local->hw, &sdata->work); 164 } 165 166 void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata) 167 { 168 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 169 170 setup_timer(&ifocb->housekeeping_timer, 171 ieee80211_ocb_housekeeping_timer, 172 (unsigned long)sdata); 173 INIT_LIST_HEAD(&ifocb->incomplete_stations); 174 spin_lock_init(&ifocb->incomplete_lock); 175 } 176 177 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata, 178 struct ocb_setup *setup) 179 { 180 struct ieee80211_local *local = sdata->local; 181 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 182 u32 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID; 183 int err; 184 185 if (ifocb->joined == true) 186 return -EINVAL; 187 188 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 189 sdata->smps_mode = IEEE80211_SMPS_OFF; 190 sdata->needed_rx_chains = sdata->local->rx_chains; 191 192 mutex_lock(&sdata->local->mtx); 193 err = ieee80211_vif_use_channel(sdata, &setup->chandef, 194 IEEE80211_CHANCTX_SHARED); 195 mutex_unlock(&sdata->local->mtx); 196 if (err) 197 return err; 198 199 ieee80211_bss_info_change_notify(sdata, changed); 200 201 ifocb->joined = true; 202 203 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 204 ieee80211_queue_work(&local->hw, &sdata->work); 205 206 netif_carrier_on(sdata->dev); 207 return 0; 208 } 209 210 int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata) 211 { 212 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 213 struct ieee80211_local *local = sdata->local; 214 struct sta_info *sta; 215 216 ifocb->joined = false; 217 sta_info_flush(sdata); 218 219 spin_lock_bh(&ifocb->incomplete_lock); 220 while (!list_empty(&ifocb->incomplete_stations)) { 221 sta = list_first_entry(&ifocb->incomplete_stations, 222 struct sta_info, list); 223 list_del(&sta->list); 224 spin_unlock_bh(&ifocb->incomplete_lock); 225 226 sta_info_free(local, sta); 227 spin_lock_bh(&ifocb->incomplete_lock); 228 } 229 spin_unlock_bh(&ifocb->incomplete_lock); 230 231 netif_carrier_off(sdata->dev); 232 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); 233 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB); 234 235 mutex_lock(&sdata->local->mtx); 236 ieee80211_vif_release_channel(sdata); 237 mutex_unlock(&sdata->local->mtx); 238 239 skb_queue_purge(&sdata->skb_queue); 240 241 del_timer_sync(&sdata->u.ocb.housekeeping_timer); 242 /* If the timer fired while we waited for it, it will have 243 * requeued the work. Now the work will be running again 244 * but will not rearm the timer again because it checks 245 * whether we are connected to the network or not -- at this 246 * point we shouldn't be anymore. 247 */ 248 249 return 0; 250 } 251