1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Portions
4 * Copyright (C) 2022-2023 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
57const 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
88const 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
102int __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 lockdep_assert_wiphy(wdev->wiphy);
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 struct ieee80211_supported_band *sband =
176 rdev->wiphy.bands[setup->chandef.chan->band];
177
178 if (setup->chandef.chan->band == NL80211_BAND_2GHZ) {
179 int i;
180
181 /*
182 * Older versions selected the mandatory rates for
183 * 2.4 GHz as well, but were broken in that only
184 * 1 Mbps was regarded as a mandatory rate. Keep
185 * using just 1 Mbps as the default basic rate for
186 * mesh to be interoperable with older versions.
187 */
188 for (i = 0; i < sband->n_bitrates; i++) {
189 if (sband->bitrates[i].bitrate == 10) {
190 setup->basic_rates = BIT(i);
191 break;
192 }
193 }
194 } else {
195 setup->basic_rates = ieee80211_mandatory_rates(sband);
196 }
197 }
198
199 err = cfg80211_chandef_dfs_required(wiphy: &rdev->wiphy,
200 chandef: &setup->chandef,
201 iftype: NL80211_IFTYPE_MESH_POINT);
202 if (err < 0)
203 return err;
204 if (err > 0 && !setup->userspace_handles_dfs)
205 return -EINVAL;
206
207 if (!cfg80211_reg_can_beacon(wiphy: &rdev->wiphy, chandef: &setup->chandef,
208 iftype: NL80211_IFTYPE_MESH_POINT))
209 return -EINVAL;
210
211 err = rdev_join_mesh(rdev, dev, conf, setup);
212 if (!err) {
213 memcpy(wdev->u.mesh.id, setup->mesh_id, setup->mesh_id_len);
214 wdev->u.mesh.id_len = setup->mesh_id_len;
215 wdev->u.mesh.chandef = setup->chandef;
216 wdev->u.mesh.beacon_interval = setup->beacon_interval;
217 }
218
219 return err;
220}
221
222int cfg80211_set_mesh_channel(struct cfg80211_registered_device *rdev,
223 struct wireless_dev *wdev,
224 struct cfg80211_chan_def *chandef)
225{
226 int err;
227
228 /*
229 * Workaround for libertas (only!), it puts the interface
230 * into mesh mode but doesn't implement join_mesh. Instead,
231 * it is configured via sysfs and then joins the mesh when
232 * you set the channel. Note that the libertas mesh isn't
233 * compatible with 802.11 mesh.
234 */
235 if (rdev->ops->libertas_set_mesh_channel) {
236 if (chandef->width != NL80211_CHAN_WIDTH_20_NOHT)
237 return -EINVAL;
238
239 if (!netif_running(dev: wdev->netdev))
240 return -ENETDOWN;
241
242 err = rdev_libertas_set_mesh_channel(rdev, dev: wdev->netdev,
243 chan: chandef->chan);
244 if (!err)
245 wdev->u.mesh.chandef = *chandef;
246
247 return err;
248 }
249
250 if (wdev->u.mesh.id_len)
251 return -EBUSY;
252
253 wdev->u.mesh.preset_chandef = *chandef;
254 return 0;
255}
256
257int cfg80211_leave_mesh(struct cfg80211_registered_device *rdev,
258 struct net_device *dev)
259{
260 struct wireless_dev *wdev = dev->ieee80211_ptr;
261 int err;
262
263 lockdep_assert_wiphy(wdev->wiphy);
264
265 if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_MESH_POINT)
266 return -EOPNOTSUPP;
267
268 if (!rdev->ops->leave_mesh)
269 return -EOPNOTSUPP;
270
271 if (!wdev->u.mesh.id_len)
272 return -ENOTCONN;
273
274 err = rdev_leave_mesh(rdev, dev);
275 if (!err) {
276 wdev->conn_owner_nlportid = 0;
277 wdev->u.mesh.id_len = 0;
278 wdev->u.mesh.beacon_interval = 0;
279 memset(&wdev->u.mesh.chandef, 0,
280 sizeof(wdev->u.mesh.chandef));
281 rdev_set_qos_map(rdev, dev, NULL);
282 cfg80211_sched_dfs_chan_update(rdev);
283 }
284
285 return err;
286}
287

source code of linux/net/wireless/mesh.c