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 * Copyright (C) 2022 Intel Corporation
8 * Author: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
9 * Funded by: Volkswagen Group Research
10 */
11
12 #include <linux/delay.h>
13 #include <linux/if_ether.h>
14 #include <linux/skbuff.h>
15 #include <linux/if_arp.h>
16 #include <linux/etherdevice.h>
17 #include <linux/rtnetlink.h>
18 #include <net/mac80211.h>
19 #include <asm/unaligned.h>
20
21 #include "ieee80211_i.h"
22 #include "driver-ops.h"
23 #include "rate.h"
24
25 #define IEEE80211_OCB_HOUSEKEEPING_INTERVAL (60 * HZ)
26 #define IEEE80211_OCB_PEER_INACTIVITY_LIMIT (240 * HZ)
27 #define IEEE80211_OCB_MAX_STA_ENTRIES 128
28
29 /**
30 * enum ocb_deferred_task_flags - mac80211 OCB deferred tasks
31 * @OCB_WORK_HOUSEKEEPING: run the periodic OCB housekeeping tasks
32 *
33 * These flags are used in @wrkq_flags field of &struct ieee80211_if_ocb
34 */
35 enum ocb_deferred_task_flags {
36 OCB_WORK_HOUSEKEEPING,
37 };
38
ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data * sdata,const u8 * bssid,const u8 * addr,u32 supp_rates)39 void ieee80211_ocb_rx_no_sta(struct ieee80211_sub_if_data *sdata,
40 const u8 *bssid, const u8 *addr,
41 u32 supp_rates)
42 {
43 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
44 struct ieee80211_local *local = sdata->local;
45 struct ieee80211_chanctx_conf *chanctx_conf;
46 struct ieee80211_supported_band *sband;
47 enum nl80211_bss_scan_width scan_width;
48 struct sta_info *sta;
49 int band;
50
51 /* XXX: Consider removing the least recently used entry and
52 * allow new one to be added.
53 */
54 if (local->num_sta >= IEEE80211_OCB_MAX_STA_ENTRIES) {
55 net_info_ratelimited("%s: No room for a new OCB STA entry %pM\n",
56 sdata->name, addr);
57 return;
58 }
59
60 ocb_dbg(sdata, "Adding new OCB station %pM\n", addr);
61
62 rcu_read_lock();
63 chanctx_conf = rcu_dereference(sdata->vif.bss_conf.chanctx_conf);
64 if (WARN_ON_ONCE(!chanctx_conf)) {
65 rcu_read_unlock();
66 return;
67 }
68 band = chanctx_conf->def.chan->band;
69 scan_width = cfg80211_chandef_to_scan_width(&chanctx_conf->def);
70 rcu_read_unlock();
71
72 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
73 if (!sta)
74 return;
75
76 /* Add only mandatory rates for now */
77 sband = local->hw.wiphy->bands[band];
78 sta->sta.deflink.supp_rates[band] =
79 ieee80211_mandatory_rates(sband, scan_width);
80
81 spin_lock(&ifocb->incomplete_lock);
82 list_add(&sta->list, &ifocb->incomplete_stations);
83 spin_unlock(&ifocb->incomplete_lock);
84 ieee80211_queue_work(&local->hw, &sdata->work);
85 }
86
ieee80211_ocb_finish_sta(struct sta_info * sta)87 static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta)
88 __acquires(RCU)
89 {
90 struct ieee80211_sub_if_data *sdata = sta->sdata;
91 u8 addr[ETH_ALEN];
92
93 memcpy(addr, sta->sta.addr, ETH_ALEN);
94
95 ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n",
96 addr, sdata->name);
97
98 sta_info_move_state(sta, IEEE80211_STA_AUTH);
99 sta_info_move_state(sta, IEEE80211_STA_ASSOC);
100 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
101
102 rate_control_rate_init(sta);
103
104 /* If it fails, maybe we raced another insertion? */
105 if (sta_info_insert_rcu(sta))
106 return sta_info_get(sdata, addr);
107 return sta;
108 }
109
ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data * sdata)110 static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata)
111 {
112 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
113
114 ocb_dbg(sdata, "Running ocb housekeeping\n");
115
116 ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT);
117
118 mod_timer(&ifocb->housekeeping_timer,
119 round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL));
120 }
121
ieee80211_ocb_work(struct ieee80211_sub_if_data * sdata)122 void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata)
123 {
124 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
125 struct sta_info *sta;
126
127 if (ifocb->joined != true)
128 return;
129
130 sdata_lock(sdata);
131
132 spin_lock_bh(&ifocb->incomplete_lock);
133 while (!list_empty(&ifocb->incomplete_stations)) {
134 sta = list_first_entry(&ifocb->incomplete_stations,
135 struct sta_info, list);
136 list_del(&sta->list);
137 spin_unlock_bh(&ifocb->incomplete_lock);
138
139 ieee80211_ocb_finish_sta(sta);
140 rcu_read_unlock();
141 spin_lock_bh(&ifocb->incomplete_lock);
142 }
143 spin_unlock_bh(&ifocb->incomplete_lock);
144
145 if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags))
146 ieee80211_ocb_housekeeping(sdata);
147
148 sdata_unlock(sdata);
149 }
150
ieee80211_ocb_housekeeping_timer(struct timer_list * t)151 static void ieee80211_ocb_housekeeping_timer(struct timer_list *t)
152 {
153 struct ieee80211_sub_if_data *sdata =
154 from_timer(sdata, t, u.ocb.housekeeping_timer);
155 struct ieee80211_local *local = sdata->local;
156 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
157
158 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
159
160 ieee80211_queue_work(&local->hw, &sdata->work);
161 }
162
ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data * sdata)163 void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
164 {
165 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
166
167 timer_setup(&ifocb->housekeeping_timer,
168 ieee80211_ocb_housekeeping_timer, 0);
169 INIT_LIST_HEAD(&ifocb->incomplete_stations);
170 spin_lock_init(&ifocb->incomplete_lock);
171 }
172
ieee80211_ocb_join(struct ieee80211_sub_if_data * sdata,struct ocb_setup * setup)173 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
174 struct ocb_setup *setup)
175 {
176 struct ieee80211_local *local = sdata->local;
177 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
178 u32 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID;
179 int err;
180
181 if (ifocb->joined == true)
182 return -EINVAL;
183
184 sdata->deflink.operating_11g_mode = true;
185 sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
186 sdata->deflink.needed_rx_chains = sdata->local->rx_chains;
187
188 mutex_lock(&sdata->local->mtx);
189 err = ieee80211_link_use_channel(&sdata->deflink, &setup->chandef,
190 IEEE80211_CHANCTX_SHARED);
191 mutex_unlock(&sdata->local->mtx);
192 if (err)
193 return err;
194
195 ieee80211_bss_info_change_notify(sdata, changed);
196
197 ifocb->joined = true;
198
199 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
200 ieee80211_queue_work(&local->hw, &sdata->work);
201
202 netif_carrier_on(sdata->dev);
203 return 0;
204 }
205
ieee80211_ocb_leave(struct ieee80211_sub_if_data * sdata)206 int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata)
207 {
208 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
209 struct ieee80211_local *local = sdata->local;
210 struct sta_info *sta;
211
212 ifocb->joined = false;
213 sta_info_flush(sdata);
214
215 spin_lock_bh(&ifocb->incomplete_lock);
216 while (!list_empty(&ifocb->incomplete_stations)) {
217 sta = list_first_entry(&ifocb->incomplete_stations,
218 struct sta_info, list);
219 list_del(&sta->list);
220 spin_unlock_bh(&ifocb->incomplete_lock);
221
222 sta_info_free(local, sta);
223 spin_lock_bh(&ifocb->incomplete_lock);
224 }
225 spin_unlock_bh(&ifocb->incomplete_lock);
226
227 netif_carrier_off(sdata->dev);
228 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
229 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB);
230
231 mutex_lock(&sdata->local->mtx);
232 ieee80211_link_release_channel(&sdata->deflink);
233 mutex_unlock(&sdata->local->mtx);
234
235 skb_queue_purge(&sdata->skb_queue);
236
237 del_timer_sync(&sdata->u.ocb.housekeeping_timer);
238 /* If the timer fired while we waited for it, it will have
239 * requeued the work. Now the work will be running again
240 * but will not rearm the timer again because it checks
241 * whether we are connected to the network or not -- at this
242 * point we shouldn't be anymore.
243 */
244
245 return 0;
246 }
247