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