1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Portions
4 * Copyright (C) 2022 Intel Corporation
5 */
6 #include <linux/ieee80211.h>
7 #include <linux/export.h>
8 #include <net/cfg80211.h>
9 #include "nl80211.h"
10 #include "core.h"
11 #include "rdev-ops.h"
12
13 /* Default values, timeouts in ms */
14 #define MESH_TTL 31
15 #define MESH_DEFAULT_ELEMENT_TTL 31
16 #define MESH_MAX_RETR 3
17 #define MESH_RET_T 100
18 #define MESH_CONF_T 100
19 #define MESH_HOLD_T 100
20
21 #define MESH_PATH_TIMEOUT 5000
22 #define MESH_RANN_INTERVAL 5000
23 #define MESH_PATH_TO_ROOT_TIMEOUT 6000
24 #define MESH_ROOT_INTERVAL 5000
25 #define MESH_ROOT_CONFIRMATION_INTERVAL 2000
26 #define MESH_DEFAULT_PLINK_TIMEOUT 1800 /* timeout in seconds */
27
28 /*
29 * Minimum interval between two consecutive PREQs originated by the same
30 * interface
31 */
32 #define MESH_PREQ_MIN_INT 10
33 #define MESH_PERR_MIN_INT 100
34 #define MESH_DIAM_TRAVERSAL_TIME 50
35
36 #define MESH_RSSI_THRESHOLD 0
37
38 /*
39 * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds
40 * before timing out. This way it will remain ACTIVE and no data frames
41 * will be unnecessarily held in the pending queue.
42 */
43 #define MESH_PATH_REFRESH_TIME 1000
44 #define MESH_MIN_DISCOVERY_TIMEOUT (2 * MESH_DIAM_TRAVERSAL_TIME)
45
46 /* Default maximum number of established plinks per interface */
47 #define MESH_MAX_ESTAB_PLINKS 32
48
49 #define MESH_MAX_PREQ_RETRIES 4
50
51 #define MESH_SYNC_NEIGHBOR_OFFSET_MAX 50
52
53 #define MESH_DEFAULT_BEACON_INTERVAL 1000 /* in 1024 us units (=TUs) */
54 #define MESH_DEFAULT_DTIM_PERIOD 2
55 #define MESH_DEFAULT_AWAKE_WINDOW 10 /* in 1024 us units (=TUs) */
56
57 const struct mesh_config default_mesh_config = {
58 .dot11MeshRetryTimeout = MESH_RET_T,
59 .dot11MeshConfirmTimeout = MESH_CONF_T,
60 .dot11MeshHoldingTimeout = MESH_HOLD_T,
61 .dot11MeshMaxRetries = MESH_MAX_RETR,
62 .dot11MeshTTL = MESH_TTL,
63 .element_ttl = MESH_DEFAULT_ELEMENT_TTL,
64 .auto_open_plinks = true,
65 .dot11MeshMaxPeerLinks = MESH_MAX_ESTAB_PLINKS,
66 .dot11MeshNbrOffsetMaxNeighbor = MESH_SYNC_NEIGHBOR_OFFSET_MAX,
67 .dot11MeshHWMPactivePathTimeout = MESH_PATH_TIMEOUT,
68 .dot11MeshHWMPpreqMinInterval = MESH_PREQ_MIN_INT,
69 .dot11MeshHWMPperrMinInterval = MESH_PERR_MIN_INT,
70 .dot11MeshHWMPnetDiameterTraversalTime = MESH_DIAM_TRAVERSAL_TIME,
71 .dot11MeshHWMPmaxPREQretries = MESH_MAX_PREQ_RETRIES,
72 .path_refresh_time = MESH_PATH_REFRESH_TIME,
73 .min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
74 .dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL,
75 .dot11MeshGateAnnouncementProtocol = false,
76 .dot11MeshForwarding = true,
77 .rssi_threshold = MESH_RSSI_THRESHOLD,
78 .ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED,
79 .dot11MeshHWMPactivePathToRootTimeout = MESH_PATH_TO_ROOT_TIMEOUT,
80 .dot11MeshHWMProotInterval = MESH_ROOT_INTERVAL,
81 .dot11MeshHWMPconfirmationInterval = MESH_ROOT_CONFIRMATION_INTERVAL,
82 .power_mode = NL80211_MESH_POWER_ACTIVE,
83 .dot11MeshAwakeWindowDuration = MESH_DEFAULT_AWAKE_WINDOW,
84 .plink_timeout = MESH_DEFAULT_PLINK_TIMEOUT,
85 .dot11MeshNolearn = false,
86 };
87
88 const struct mesh_setup default_mesh_setup = {
89 /* cfg80211_join_mesh() will pick a channel if needed */
90 .sync_method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET,
91 .path_sel_proto = IEEE80211_PATH_PROTOCOL_HWMP,
92 .path_metric = IEEE80211_PATH_METRIC_AIRTIME,
93 .auth_id = 0, /* open */
94 .ie = NULL,
95 .ie_len = 0,
96 .is_secure = false,
97 .user_mpm = false,
98 .beacon_interval = MESH_DEFAULT_BEACON_INTERVAL,
99 .dtim_period = MESH_DEFAULT_DTIM_PERIOD,
100 };
101
__cfg80211_join_mesh(struct cfg80211_registered_device * rdev,struct net_device * dev,struct mesh_setup * setup,const struct mesh_config * conf)102 int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
103 struct net_device *dev,
104 struct mesh_setup *setup,
105 const struct mesh_config *conf)
106 {
107 struct wireless_dev *wdev = dev->ieee80211_ptr;
108 int err;
109
110 BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
111
112 ASSERT_WDEV_LOCK(wdev);
113
114 if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
115 return -EOPNOTSUPP;
116
117 if (!(rdev->wiphy.flags & WIPHY_FLAG_MESH_AUTH) &&
118 setup->is_secure)
119 return -EOPNOTSUPP;
120
121 if (wdev->u.mesh.id_len)
122 return -EALREADY;
123
124 if (!setup->mesh_id_len)
125 return -EINVAL;
126
127 if (!rdev->ops->join_mesh)
128 return -EOPNOTSUPP;
129
130 if (!setup->chandef.chan) {
131 /* if no channel explicitly given, use preset channel */
132 setup->chandef = wdev->u.mesh.preset_chandef;
133 }
134
135 if (!setup->chandef.chan) {
136 /* if we don't have that either, use the first usable channel */
137 enum nl80211_band band;
138
139 for (band = 0; band < NUM_NL80211_BANDS; band++) {
140 struct ieee80211_supported_band *sband;
141 struct ieee80211_channel *chan;
142 int i;
143
144 sband = rdev->wiphy.bands[band];
145 if (!sband)
146 continue;
147
148 for (i = 0; i < sband->n_channels; i++) {
149 chan = &sband->channels[i];
150 if (chan->flags & (IEEE80211_CHAN_NO_IR |
151 IEEE80211_CHAN_DISABLED |
152 IEEE80211_CHAN_RADAR))
153 continue;
154 setup->chandef.chan = chan;
155 break;
156 }
157
158 if (setup->chandef.chan)
159 break;
160 }
161
162 /* no usable channel ... */
163 if (!setup->chandef.chan)
164 return -EINVAL;
165
166 setup->chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
167 setup->chandef.center_freq1 = setup->chandef.chan->center_freq;
168 }
169
170 /*
171 * check if basic rates are available otherwise use mandatory rates as
172 * basic rates
173 */
174 if (!setup->basic_rates) {
175 enum nl80211_bss_scan_width scan_width;
176 struct ieee80211_supported_band *sband =
177 rdev->wiphy.bands[setup->chandef.chan->band];
178
179 if (setup->chandef.chan->band == NL80211_BAND_2GHZ) {
180 int i;
181
182 /*
183 * Older versions selected the mandatory rates for
184 * 2.4 GHz as well, but were broken in that only
185 * 1 Mbps was regarded as a mandatory rate. Keep
186 * using just 1 Mbps as the default basic rate for
187 * mesh to be interoperable with older versions.
188 */
189 for (i = 0; i < sband->n_bitrates; i++) {
190 if (sband->bitrates[i].bitrate == 10) {
191 setup->basic_rates = BIT(i);
192 break;
193 }
194 }
195 } else {
196 scan_width = cfg80211_chandef_to_scan_width(&setup->chandef);
197 setup->basic_rates = ieee80211_mandatory_rates(sband,
198 scan_width);
199 }
200 }
201
202 err = cfg80211_chandef_dfs_required(&rdev->wiphy,
203 &setup->chandef,
204 NL80211_IFTYPE_MESH_POINT);
205 if (err < 0)
206 return err;
207 if (err > 0 && !setup->userspace_handles_dfs)
208 return -EINVAL;
209
210 if (!cfg80211_reg_can_beacon(&rdev->wiphy, &setup->chandef,
211 NL80211_IFTYPE_MESH_POINT))
212 return -EINVAL;
213
214 err = rdev_join_mesh(rdev, dev, conf, setup);
215 if (!err) {
216 memcpy(wdev->u.mesh.id, setup->mesh_id, setup->mesh_id_len);
217 wdev->u.mesh.id_len = setup->mesh_id_len;
218 wdev->u.mesh.chandef = setup->chandef;
219 wdev->u.mesh.beacon_interval = setup->beacon_interval;
220 }
221
222 return err;
223 }
224
cfg80211_set_mesh_channel(struct cfg80211_registered_device * rdev,struct wireless_dev * wdev,struct cfg80211_chan_def * chandef)225 int cfg80211_set_mesh_channel(struct cfg80211_registered_device *rdev,
226 struct wireless_dev *wdev,
227 struct cfg80211_chan_def *chandef)
228 {
229 int err;
230
231 /*
232 * Workaround for libertas (only!), it puts the interface
233 * into mesh mode but doesn't implement join_mesh. Instead,
234 * it is configured via sysfs and then joins the mesh when
235 * you set the channel. Note that the libertas mesh isn't
236 * compatible with 802.11 mesh.
237 */
238 if (rdev->ops->libertas_set_mesh_channel) {
239 if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
240 return -EINVAL;
241
242 if (!netif_running(wdev->netdev))
243 return -ENETDOWN;
244
245 err = rdev_libertas_set_mesh_channel(rdev, wdev->netdev,
246 chandef->chan);
247 if (!err)
248 wdev->u.mesh.chandef = *chandef;
249
250 return err;
251 }
252
253 if (wdev->u.mesh.id_len)
254 return -EBUSY;
255
256 wdev->u.mesh.preset_chandef = *chandef;
257 return 0;
258 }
259
__cfg80211_leave_mesh(struct cfg80211_registered_device * rdev,struct net_device * dev)260 int __cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
261 struct net_device *dev)
262 {
263 struct wireless_dev *wdev = dev->ieee80211_ptr;
264 int err;
265
266 ASSERT_WDEV_LOCK(wdev);
267
268 if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
269 return -EOPNOTSUPP;
270
271 if (!rdev->ops->leave_mesh)
272 return -EOPNOTSUPP;
273
274 if (!wdev->u.mesh.id_len)
275 return -ENOTCONN;
276
277 err = rdev_leave_mesh(rdev, dev);
278 if (!err) {
279 wdev->conn_owner_nlportid = 0;
280 wdev->u.mesh.id_len = 0;
281 wdev->u.mesh.beacon_interval = 0;
282 memset(&wdev->u.mesh.chandef, 0,
283 sizeof(wdev->u.mesh.chandef));
284 rdev_set_qos_map(rdev, dev, NULL);
285 cfg80211_sched_dfs_chan_update(rdev);
286 }
287
288 return err;
289 }
290
cfg80211_leave_mesh(struct cfg80211_registered_device * rdev,struct net_device * dev)291 int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
292 struct net_device *dev)
293 {
294 struct wireless_dev *wdev = dev->ieee80211_ptr;
295 int err;
296
297 wdev_lock(wdev);
298 err = __cfg80211_leave_mesh(rdev, dev);
299 wdev_unlock(wdev);
300
301 return err;
302 }
303