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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 - 2024 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 <linux/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 */
35enum ocb_deferred_task_flags {
36 OCB_WORK_HOUSEKEEPING,
37};
38
39void 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 if (!ifocb->joined)
51 return;
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.bss_conf.chanctx_conf);
66 if (WARN_ON_ONCE(!chanctx_conf)) {
67 rcu_read_unlock();
68 return;
69 }
70 band = chanctx_conf->def.chan->band;
71 rcu_read_unlock();
72
73 sta = sta_info_alloc(sdata, addr, GFP_ATOMIC);
74 if (!sta)
75 return;
76
77 /* Add only mandatory rates for now */
78 sband = local->hw.wiphy->bands[band];
79 sta->sta.deflink.supp_rates[band] = ieee80211_mandatory_rates(sband);
80
81 spin_lock(&ifocb->incomplete_lock);
82 list_add(&sta->list, &ifocb->incomplete_stations);
83 spin_unlock(&ifocb->incomplete_lock);
84 wiphy_work_queue(local->hw.wiphy, &sdata->work);
85}
86
87static 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->deflink);
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
110static 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
122void 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 lockdep_assert_wiphy(sdata->local->hw.wiphy);
128
129 if (ifocb->joined != true)
130 return;
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
149static void ieee80211_ocb_housekeeping_timer(struct timer_list *t)
150{
151 struct ieee80211_sub_if_data *sdata =
152 timer_container_of(sdata, t, u.ocb.housekeeping_timer);
153 struct ieee80211_local *local = sdata->local;
154 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
155
156 set_bit(OCB_WORK_HOUSEKEEPING, &ifocb->wrkq_flags);
157
158 wiphy_work_queue(local->hw.wiphy, &sdata->work);
159}
160
161void ieee80211_ocb_setup_sdata(struct ieee80211_sub_if_data *sdata)
162{
163 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
164
165 timer_setup(&ifocb->housekeeping_timer,
166 ieee80211_ocb_housekeeping_timer, 0);
167 INIT_LIST_HEAD(&ifocb->incomplete_stations);
168 spin_lock_init(&ifocb->incomplete_lock);
169}
170
171int ieee80211_ocb_join(struct ieee80211_sub_if_data *sdata,
172 struct ocb_setup *setup)
173{
174 struct ieee80211_chan_req chanreq = { .oper = setup->chandef };
175 struct ieee80211_local *local = sdata->local;
176 struct ieee80211_if_ocb *ifocb = &sdata->u.ocb;
177 u64 changed = BSS_CHANGED_OCB | BSS_CHANGED_BSSID;
178 int err;
179
180 lockdep_assert_wiphy(sdata->local->hw.wiphy);
181
182 if (ifocb->joined == true)
183 return -EINVAL;
184
185 sdata->deflink.operating_11g_mode = true;
186 sdata->deflink.smps_mode = IEEE80211_SMPS_OFF;
187 sdata->deflink.needed_rx_chains = sdata->local->rx_chains;
188
189 err = ieee80211_link_use_channel(&sdata->deflink, &chanreq,
190 IEEE80211_CHANCTX_SHARED);
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 wiphy_work_queue(local->hw.wiphy, &sdata->work);
200
201 netif_carrier_on(sdata->dev);
202 return 0;
203}
204
205int 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 lockdep_assert_wiphy(sdata->local->hw.wiphy);
212
213 ifocb->joined = false;
214 sta_info_flush(sdata, -1);
215
216 spin_lock_bh(&ifocb->incomplete_lock);
217 while (!list_empty(&ifocb->incomplete_stations)) {
218 sta = list_first_entry(&ifocb->incomplete_stations,
219 struct sta_info, list);
220 list_del(&sta->list);
221 spin_unlock_bh(&ifocb->incomplete_lock);
222
223 sta_info_free(local, sta);
224 spin_lock_bh(&ifocb->incomplete_lock);
225 }
226 spin_unlock_bh(&ifocb->incomplete_lock);
227
228 netif_carrier_off(sdata->dev);
229 clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
230 ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_OCB);
231
232 ieee80211_link_release_channel(&sdata->deflink);
233
234 skb_queue_purge(&sdata->skb_queue);
235
236 timer_delete_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}