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 /* Add only mandatory rates for now */ 79 sband = local->hw.wiphy->bands[band]; 80 sta->sta.supp_rates[band] = 81 ieee80211_mandatory_rates(sband, scan_width); 82 83 spin_lock(&ifocb->incomplete_lock); 84 list_add(&sta->list, &ifocb->incomplete_stations); 85 spin_unlock(&ifocb->incomplete_lock); 86 ieee80211_queue_work(&local->hw, &sdata->work); 87 } 88 89 static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta) 90 __acquires(RCU) 91 { 92 struct ieee80211_sub_if_data *sdata = sta->sdata; 93 u8 addr[ETH_ALEN]; 94 95 memcpy(addr, sta->sta.addr, ETH_ALEN); 96 97 ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n", 98 addr, sdata->name); 99 100 sta_info_move_state(sta, IEEE80211_STA_AUTH); 101 sta_info_move_state(sta, IEEE80211_STA_ASSOC); 102 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED); 103 104 rate_control_rate_init(sta); 105 106 /* If it fails, maybe we raced another insertion? */ 107 if (sta_info_insert_rcu(sta)) 108 return sta_info_get(sdata, addr); 109 return sta; 110 } 111 112 static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata) 113 { 114 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 115 116 ocb_dbg(sdata, "Running ocb housekeeping\n"); 117 118 ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT); 119 120 mod_timer(&ifocb->housekeeping_timer, 121 round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL)); 122 } 123 124 void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata) 125 { 126 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 127 struct sta_info *sta; 128 129 if (ifocb->joined != true) 130 return; 131 132 sdata_lock(sdata); 133 134 spin_lock_bh(&ifocb->incomplete_lock); 135 while (!list_empty(&ifocb->incomplete_stations)) { 136 sta = list_first_entry(&ifocb->incomplete_stations, 137 struct sta_info, list); 138 list_del(&sta->list); 139 spin_unlock_bh(&ifocb->incomplete_lock); 140 141 ieee80211_ocb_finish_sta(sta); 142 rcu_read_unlock(); 143 spin_lock_bh(&ifocb->incomplete_lock); 144 } 145 spin_unlock_bh(&ifocb->incomplete_lock); 146 147 if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags)) 148 ieee80211_ocb_housekeeping(sdata); 149 150 sdata_unlock(sdata); 151 } 152 153 static void ieee80211_ocb_housekeeping_timer(unsigned long data) 154 { 155 struct ieee80211_sub_if_data *sdata = (void *)data; 156 struct ieee80211_local *local = sdata->local; 157 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 158 159 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 160 161 ieee80211_queue_work(&local->hw, &sdata->work); 162 } 163 164 void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata) 165 { 166 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 167 168 setup_timer(&ifocb->housekeeping_timer, 169 ieee80211_ocb_housekeeping_timer, 170 (unsigned long)sdata); 171 INIT_LIST_HEAD(&ifocb->incomplete_stations); 172 spin_lock_init(&ifocb->incomplete_lock); 173 } 174 175 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata, 176 struct ocb_setup *setup) 177 { 178 struct ieee80211_local *local = sdata->local; 179 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 180 u32 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID; 181 int err; 182 183 if (ifocb->joined == true) 184 return -EINVAL; 185 186 sdata->flags |= IEEE80211_SDATA_OPERATING_GMODE; 187 sdata->smps_mode = IEEE80211_SMPS_OFF; 188 sdata->needed_rx_chains = sdata->local->rx_chains; 189 190 mutex_lock(&sdata->local->mtx); 191 err = ieee80211_vif_use_channel(sdata, &setup->chandef, 192 IEEE80211_CHANCTX_SHARED); 193 mutex_unlock(&sdata->local->mtx); 194 if (err) 195 return err; 196 197 ieee80211_bss_info_change_notify(sdata, changed); 198 199 ifocb->joined = true; 200 201 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags); 202 ieee80211_queue_work(&local->hw, &sdata->work); 203 204 netif_carrier_on(sdata->dev); 205 return 0; 206 } 207 208 int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata) 209 { 210 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb; 211 struct ieee80211_local *local = sdata->local; 212 struct sta_info *sta; 213 214 ifocb->joined = false; 215 sta_info_flush(sdata); 216 217 spin_lock_bh(&ifocb->incomplete_lock); 218 while (!list_empty(&ifocb->incomplete_stations)) { 219 sta = list_first_entry(&ifocb->incomplete_stations, 220 struct sta_info, list); 221 list_del(&sta->list); 222 spin_unlock_bh(&ifocb->incomplete_lock); 223 224 sta_info_free(local, sta); 225 spin_lock_bh(&ifocb->incomplete_lock); 226 } 227 spin_unlock_bh(&ifocb->incomplete_lock); 228 229 netif_carrier_off(sdata->dev); 230 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); 231 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB); 232 233 mutex_lock(&sdata->local->mtx); 234 ieee80211_vif_release_channel(sdata); 235 mutex_unlock(&sdata->local->mtx); 236 237 skb_queue_purge(&sdata->skb_queue); 238 239 del_timer_sync(&sdata->u.ocb.housekeeping_timer); 240 /* If the timer fired while we waited for it, it will have 241 * requeued the work. Now the work will be running again 242 * but will not rearm the timer again because it checks 243 * whether we are connected to the network or not -- at this 244 * point we shouldn't be anymore. 245 */ 246 247 return 0; 248 } 249