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 - 2023 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
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 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.bss_conf.chanctx_conf);
63 if (WARN_ON_ONCE(!chanctx_conf)) {
64 rcu_read_unlock();
65 return;
66 }
67 band = chanctx_conf->def.chan->band;
68 rcu_read_unlock();
69
70 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
71 if (!sta)
72 return;
73
74 /* Add only mandatory rates for now */
75 sband = local->hw.wiphy->bands[band];
76 sta->sta.deflink.supp_rates[band] = ieee80211_mandatory_rates(sband);
77
78 spin_lock(&ifocb->incomplete_lock);
79 list_add(&sta->list, &ifocb->incomplete_stations);
80 spin_unlock(&ifocb->incomplete_lock);
81 wiphy_work_queue(local->hw.wiphy, &sdata->work);
82 }
83
84 static struct sta_info *ieee80211_ocb_finish_sta(struct sta_info *sta)
85 __acquires(RCU)
86 {
87 struct ieee80211_sub_if_data *sdata = sta->sdata;
88 u8 addr[ETH_ALEN];
89
90 memcpy(addr, sta->sta.addr, ETH_ALEN);
91
92 ocb_dbg(sdata, "Adding new IBSS station %pM (dev=%s)\n",
93 addr, sdata->name);
94
95 sta_info_move_state(sta, IEEE80211_STA_AUTH);
96 sta_info_move_state(sta, IEEE80211_STA_ASSOC);
97 sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED);
98
99 rate_control_rate_init(sta);
100
101 /* If it fails, maybe we raced another insertion? */
102 if (sta_info_insert_rcu(sta))
103 return sta_info_get(sdata, addr);
104 return sta;
105 }
106
107 static void ieee80211_ocb_housekeeping(struct ieee80211_sub_if_data *sdata)
108 {
109 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
110
111 ocb_dbg(sdata, "Running ocb housekeeping\n");
112
113 ieee80211_sta_expire(sdata, IEEE80211_OCB_PEER_INACTIVITY_LIMIT);
114
115 mod_timer(&ifocb->housekeeping_timer,
116 round_jiffies(jiffies + IEEE80211_OCB_HOUSEKEEPING_INTERVAL));
117 }
118
119 void ieee80211_ocb_work(struct ieee80211_sub_if_data *sdata)
120 {
121 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
122 struct sta_info *sta;
123
124 lockdep_assert_wiphy(sdata->local->hw.wiphy);
125
126 if (ifocb->joined != true)
127 return;
128
129 spin_lock_bh(&ifocb->incomplete_lock);
130 while (!list_empty(&ifocb->incomplete_stations)) {
131 sta = list_first_entry(&ifocb->incomplete_stations,
132 struct sta_info, list);
133 list_del(&sta->list);
134 spin_unlock_bh(&ifocb->incomplete_lock);
135
136 ieee80211_ocb_finish_sta(sta);
137 rcu_read_unlock();
138 spin_lock_bh(&ifocb->incomplete_lock);
139 }
140 spin_unlock_bh(&ifocb->incomplete_lock);
141
142 if (test_and_clear_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags))
143 ieee80211_ocb_housekeeping(sdata);
144 }
145
146 static void ieee80211_ocb_housekeeping_timer(struct timer_list *t)
147 {
148 struct ieee80211_sub_if_data *sdata =
149 from_timer(sdata, t, u.ocb.housekeeping_timer);
150 struct ieee80211_local *local = sdata->local;
151 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
152
153 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
154
155 wiphy_work_queue(local->hw.wiphy, &sdata->work);
156 }
157
158 void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
159 {
160 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
161
162 timer_setup(&ifocb->housekeeping_timer,
163 ieee80211_ocb_housekeeping_timer, 0);
164 INIT_LIST_HEAD(&ifocb->incomplete_stations);
165 spin_lock_init(&ifocb->incomplete_lock);
166 }
167
168 int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
169 struct ocb_setup *setup)
170 {
171 struct ieee80211_chan_req chanreq = { .oper = setup->chandef };
172 struct ieee80211_local *local = sdata->local;
173 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
174 u64 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID;
175 int err;
176
177 lockdep_assert_wiphy(sdata->local->hw.wiphy);
178
179 if (ifocb->joined == true)
180 return -EINVAL;
181
182 sdata->deflink.operating_11g_mode = true;
183 sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
184 sdata->deflink.needed_rx_chains = sdata->local->rx_chains;
185
186 err = ieee80211_link_use_channel(&sdata->deflink, &chanreq,
187 IEEE80211_CHANCTX_SHARED);
188 if (err)
189 return err;
190
191 ieee80211_bss_info_change_notify(sdata, changed);
192
193 ifocb->joined = true;
194
195 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
196 wiphy_work_queue(local->hw.wiphy, &sdata->work);
197
198 netif_carrier_on(sdata->dev);
199 return 0;
200 }
201
202 int ieee80211_ocb_leave(struct ieee80211_sub_if_data *sdata)
203 {
204 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
205 struct ieee80211_local *local = sdata->local;
206 struct sta_info *sta;
207
208 lockdep_assert_wiphy(sdata->local->hw.wiphy);
209
210 ifocb->joined = false;
211 sta_info_flush(sdata, -1);
212
213 spin_lock_bh(&ifocb->incomplete_lock);
214 while (!list_empty(&ifocb->incomplete_stations)) {
215 sta = list_first_entry(&ifocb->incomplete_stations,
216 struct sta_info, list);
217 list_del(&sta->list);
218 spin_unlock_bh(&ifocb->incomplete_lock);
219
220 sta_info_free(local, sta);
221 spin_lock_bh(&ifocb->incomplete_lock);
222 }
223 spin_unlock_bh(&ifocb->incomplete_lock);
224
225 netif_carrier_off(sdata->dev);
226 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
227 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB);
228
229 ieee80211_link_release_channel(&sdata->deflink);
230
231 skb_queue_purge(&sdata->skb_queue);
232
233 del_timer_sync(&sdata->u.ocb.housekeeping_timer);
234 /* If the timer fired while we waited for it, it will have
235 * requeued the work. Now the work will be running again
236 * but will not rearm the timer again because it checks
237 * whether we are connected to the network or not -- at this
238 * point we shouldn't be anymore.
239 */
240
241 return 0;
242 }
243
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